COMPAGNIE THERMIQUE de SAVANNAH LtCe ......COMPAGNIE THERMIQUE de SAVANNAH LtCe CONSTRUCTION &...

COMPAGNIE THERMIQUE de SAVANNAH LtCe

CONSTRUCTION & OPERATIONof a

83.0 MW COAL / BAGASSE-FIRED POWER PLANTat

SAVANNAH

ENVIRONMENTAL IMPACT ASSESSMENT

E1 625

July 2005

S.l.G.M.A Ove Arup & PartnersConsulting Engineers

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Compagnie Thermique de Savannah

Operation of a dual coal/bagasse-fired Power Plant

at Savannah

Environmental Impact Assessment

EXECUTIVE SUMMARY

1 In January 2004 the Central Electricity Board (CEB) launched a tender for the purchase and

importation of electrical power on the National Grid. Compagnie Thermique de Savannah Ltee

(hereinafter referred to as CTSav), a public liability societe company duly registered in Mauritius

submitted an offer based on the implementation and operation of a dual coal/bagasse-fired

2x41.5MW steam power plant at La Baraque, and the construction of a 66kV transmission link

from La Baraque to Union Vale.

2 CTSav's offer has subsequently been retained. A Power Purchase Agreement (PPA) has been

substantially negotiated and concluded with the CEB on the 18 February 2005 for the sale to CEB

of about of 335GWhE per year, power importation to the National Grid being modulated in function

of customer demand (expected average production 335GWhE per year).

3 The Project will be located next to the La Baraque Sugar Factory in the district of Grand-Port -

Savane, on a plot of land owned by Savannah Sugar Estate, and released for the Project as

authenticated by a notary public. The land hitherto under cane, CTSav has submitted for the

necessary Re-zoning and Land Conversion Permit.

4 SIGMA Ove Arup & Partners Consulting Engineers, in association with Dr Alan

SAMSOON, have been commissioned for the Environmental Impact Assessment (EIA), a

mandatory exercise in conformity with the provisions of the Environment Protection Act 2002

(Mauritius).

5 Negative Impacts have been identified with the operation of the Power Plant. They are mainly

associated with:Atmospheric emissions that will decrease the ambient air quality in the region. In particular the

ambient level of Sulphur dioxide during the inter crop season when CTSav will operate on coal

as combustible.Other coal/bagasse combustion products, and ashes (bottom ash or slag, and fly ashes)

* Liquid effluents such as resin wash waters from the boiler water demineralization unit, oily and

dust contaminated waters from the Plant

* Hydrocarbon wastes (lube oil sludge, used lube oils) from the Plant

* On-site storage of coal* Intensification of lorry traffic, noise and atmospheric emissions from road transportation of coal

6. The negative impacts that could result there from can be effectively mitigated by the

implementation of the following measures:

Increasing the stack gas ejection velocity in coal-combustion mode from 10 m/s to not lower

than 20m/s susceptible of enhancing atmospheric dispersion of S02

• Collection and pretreatment of the liquid effluents to the standard prescribed for their discharge

by the appropriate Regulations

* Prevention and/ or containment of leachate from the coal stock piles

• Prevention and fighting of fires originating spontaneously from the strategy coal storage

. Collection of fly ashes for eventual incorporation in concrete as per appropriate technical

specifications, and in agreement with Construction Firms

* Collection of slag and its disposal by incorporation in civil engineering structures as per

Standard Specifications, or in a landfill

* Neutralisation of effluents from the demineralization plant and their reuse for irrigation.

An Environmental Monitoring Plan has been proposed accordingly in conformity with thie

provisions of the aforesaid Law.

7 Positive Impacts are basically of socio-economic nature. They will result from inter alia:

• availability at avoided cost to CEB, of a 83.OMWE net guaranteed production capacity

* a more efficient exploitation of bagasse, the familiar renewable biomass source of energy

. the provision of temporary employment to various professional trades during construction and

permanent employment thereafter during operation

8 Considering that the Negative Impacts are satisfactorily mitigated, and considering further the

considerable Positive Impacts of the Project in terms of low power generation costs, the Project is

recommended to the Authorities.

Patrick HAREL M.Sc., D.U.S., Ph.D.

S.I.G.M.A - Ove Arup & Partners

Associated Consulting Engineers

Compagnie Thermique de SavannahOperation of a dual coal/bagasse-fired Power Plant

at Savannah


TABLE of CONTENTS

EXECUTIVE SUMMARY .........................................................................................I

TABLE OF CONTENTS ..........................................................................................

CHAPTER 1: PROJECT BACKGROUND ................................................. 1

1.1 PROJECT OUTLINE ......................................................................................1

1.2 PROJECT JUSTIFICATION ................................................................................1

1.2.1 NEED FOR INCREASED GENERATING CAPACITY REQUIREMENTS ...................................... 1

1.2.2 PRIORITY TO RENEWABLE GENERATION TECHNOLOGIES ......................................................... 2

1.2.3 ENHANCING THE ROLE OF INDEPENDENT POWER PRODUCERS (IPPs) ......................................................... 2

1.3 LEGAL AND INSTITUTIONAL FRAMEWORK ...................................... 2

1.3.1 MNISTRY OF PUBLIC UTILITIES ...............................................................3

1.3.1.1 Power Purchase Agreement ................................................. 3

1.3.1.2 Commercial Operation Date (COD) ........................................... _ 3

1.3.2 MI NISTRY OF ENVIRONMENT ..........................................................3

1.3.2.1 Emission, Effluent Discharge and Noise Standards .................................. 3

1.3.2.2 Persistent Organic Pollutant (POPs) Emissions .................................... 3

1.3.2.3 Ashes ............................................................................................3

1.3.3 MINISTRY OF AGRICULTURE ..................................................................3

1.3.4 MINSTRY OF HOUSING & LANDS ................................................................................... 4

1.3.4.1 Town & Country Planning .................................................. 4

1.3.4.2 National Physical Development Plan .............. ........................................... 4

1.3.4.2.1 Policy E l ...................................................................4

1.3.4.2.2 PoliicyST3 .................................................... 4

1.3.4.2.3 Policy AG3 ................................................................. 4

CHAPTER 2: PROJECT PROMOTERS & ORGANISATION ................................................ 5

2.1 CENTRALE THERMIQUE DE SAVANNAH ......................................... 5

2.1.1 THE PROJECT VEICLE .................................................5

2.1.2 SHAREHOLDING .............................................................................. 5

2.2 PROCUREMENT SERVICES .................................................... 5

2.2.1 THE DUAL COAL/BAGASSE-FIRED STEAM POWER PLANT ........................................... 5

2.2.2 THE TURBO-ALTERNATOR SETS ............................. 6

2.2.3 THE POWER TRANSMISSION LINN 6

2.3 ENGINEERING SERVICES 6...........................................6

2.4 STAFFING OF THE POWER PLANT .............................................. 6

2.5 PLANT CONSTRUCTION TIME-SCHEDULE ........................................... 7

CHAPTER 3: DETAILED PROJECT DESCRIPTION ........................................ 8

3.1 THE POWER PLANT CONFIGURATION .......................................... 8

3.2 PROJECT SITE ... ................................. ...............................................

8

3.2.1 LocATION AND EXTENT..............................................................

. ...... 8

3.2.2- JUSTIFICATION OF CHOICE OF SITE ...................................... ................... 8

3.2.3 OWNERSHIP ......................................................................

9

3.2.4 PRESENT OCCUPANCY .....................................................................

9

3.3 FURNACES AND BOILERS .....................................

........... 9

3.3.1 THE FURNACES .............................................................................

9

3.3.2 THEBOILERS..............................................................................

10

3.4 TURBO-ALTERNATOR SETS ........................................ ....... 10

3.4.1 PERFORMANCE CHARACTERISTICS .......................................... ................. 10

3.4.2 SWITCHGEAR ..............................................................................

10

3.4.3 PLANT DC SYSTEM ... ..................................... ....................................................

11

3.4.4 PLANT LUBRICATION SYSTEM .............................................................................

1

3.4.4.1 Used Lube Oil Collection and Disposal ........................................I 11

3.4.5 PLANT HP HYDRAULIC CONTROL .......................................................................

11

3.5 COAL SUPPLY AND MANAGEMENT ...........................................

12

3.5.1 ORIGIN AND CHARACTERISTICS OF COL .......................................................12

3.5.2 STRATEGIC STORAGE FACILITY...............................................................

13

3.5.3 FIGHTING FIRES To ENviRONMENT ............................................................ 14

3.5.4 IN-SITU COAL HANDLING AT RECEPTION .......................................................14

3.5.5 COAL CONDITIONING UNIT..................................................................

14

3.5.6 COAL COMBUSTION PRODUCTS: CHARACTERISTICS, HANDLING, DISPOSAL ............................15

3.5.6.1 Coal Combustion Products .................................................15

3.5.6.2 Fly Ash ..............................................................

16

3.5.6.3 Slag ................................................................

16

3.5.6.4 Flue Gases Characteristics .................................................16

3.6 BAGASSE SUPPLY AND MANAGEMENT .........................................

18

3.6.1 ORIGIN OF BAGASSE ..................................................

1 8

3.6.2 CHARACTERISTICS OF BAGASSE ...........................,.18

3.6.3 BAGASSE COMBUSTION PRODUCTS: CHARACTERISTICS, HANDLING, DISPOSAL ......................... 18

3.6.3.1 Bagasse Combustion Products .............................................. 18

3.63.2 Fly Ash ................................................ ............. 19

3.6.3.3 Bottom Ash...........................................................

19

3.6.3.4 Flue Gases Characteristics ................................................

20

3.7 PROJECT INFRASTRUCTURE.................................................

21

3.7.1 POWER PLANT ACCESS

21

3.7.2 LoRRY CLEANING FACILITIES .........................

21

3.7.3 PERIPHERAL DRAIN ...................

.21

3.7.4 SETrLING PONDS ...................

.21

3.8 PROJECT WATER REQUIREMENTS ............................................

22

3.8.1 CTSAV PROCESS WATER REQUIREMENTS ....................................................

22

3.8.2 POTABLE WATER REQUIREMENTS ............................................ .............. 22

3.9 WASTE WATER FROM CTSAV ................................................ 22

3.9.1 POWER STATION PROCESS EFFLUNT ..........................................................

22

3.9.1.1 Origin and Production Rates ............................................... 22

3.9.1.2 Quality of Process Effluent Components ........................................ 23

3.9.1.3 Disposal of Power Station Process Effluent ...................................... 23

3.9.2 DOMESTIC EFFLUENTS ... ................................... .....................................................

24

3.9.2.1 Quality and Rate of Production .............................................. 24

39.2.2 Treatment andDisposal...................................................

24

3.10 GENERATION OF PROCESS WASTES ........................................... 24

3.10.1 HYDROCARBON WASTES .................................................... ........... 243.10.1.1 Production Rates ........................................................................ 243.10.1.2 Disposal ... ........... .................... ............................................... 24

3.10.2 SOLID WASTES .................................... 24

3.10.2.1 Fly Ash ... ............ .................... ............................................... 243.10.2.1.1 Production Rate ....................................................................... 243.10.2.1.2 Disposal of Fly Ash ........................... ......................................................................................................... 25

3.10.2.2 Slag ............................................................................................ 253.10.2.2.1 Production Rate ......................................................... 253.10.2.2.2 Disposal of Slag .................................................................. 25

3.10.2.3 Boiler Bottom Ash ......................................................... 25

CHAPTER 4: BUILT ENVIRONMENT OF THE PROJECT ................................... 26

4.1 DEMOGRAPHY ............................................................ 26

4.1.1 GENERAL ...................................................................................................... 264.1.2 REGIONAL SETTLEMENT & POPULATION ....................................................... 26

4.2 TOURISM & PARA-TOURISTIC ACTIVITIES ........................................................ 27

4.3 REGIONAL PUBLIC BEACHES AND RECREATIONAL SITES ..................................................... 27

4.3.1 PUBLIC BEACHES .............................................................................................. 274.3.2 RECREATIONAL SITES .......................................................................................... 27

4.4 REGIONAL INDUSTRIAL ACTIVITY ............ ............................................ 28

4.4.1 THE SUGAR INDUSTRY .......................................................................................... 284.4.2 POWER GENERATION AT COMPAGNIE THERMIQUE DU SUD (CTDS) .......................... 284.4.3 POULTRY FARMING ............................................................................................ 294.4.4 MONKEY BREEDING ............................................................................................ 29

4.5 HISTORICAL SITES ......................................................... 29

4.6 PUBLIC UTILITIES .......................................................... 29

4.6.1 DOMESTIC WATER SUPPLY.................................................................. 29

4.6.2 ELECTRICITY SUPPLY ............................................................................................ 29

4.6.2.1 Production Policy ....................................................... 304.6.2.2 Power Transmission and Distribution Network ................................... 30

4.6.3 TELECOMMUNICATIONS .......................................................................................... 30

4.6.4 SEWER NETWORKS ............................................................................................... 30

4.6.5 ROAD INFRASTRUCTURE ............................................................................................. 30

4.7 INDUSTRIAL WATER .............................................................................. 30

4.7.1 ORIGIN OF INDUSTRIAL WATER.............................................................. 30

4.7.1.1 Savannah Sugar Estate ....................... ......................... 314.7.1.2 MT-MD Sugar Estate .................................................................. 31

4.7.2 WATER RESOURCES ........................................................................ 31

4.7.2.1 Water Rights ..................................................... .......... 314.7.2.2 Water Availability .................................................................. 31

4.7.2.2.1 From Savannah Resources ...................................... 3 14.7.2.2.2 From MT-MD Resources ..................................... 32

4.7.3 INDUSTRIAL WATER NETWORK .............................................. ........... 32

CHAPTER 5: NATURAL ENVIRONMENT ............................................... 33

5.1 INTRODUCTION ................................................................... 33

5.2 CLIMATE ................................................................. 33

5.2.1 RAINFALL ........................................................................ 34

5.2.2 TEMPERATURE ............................................................................ 34

5.2.3 WIND DATA ..................................... ..................................................... 35

5.2.3.1 Wind data under normal climatic conditions ..................................... 35

5.2.3.1.1 Trade Winds .......................................................................

5.2.3.1.2 Average wind distribution ..............................................................35

5.2.3.2 Cyclonic Winds........................................................ 35

5.2.3.3 Site Exposure to Winds ...................................................36

5.3 GEOLOGY ................................................................36

5.4 PEDOLOGY ............................................................... 36

5.5 SURFACE HYDROLOGY AND HYDRO-GEOLOGY ................................. 36

5.5.1 REGIONAL SURFACE HYDROLOGY............................................................ 36

5.5.2 SITE HYDROLOGY.......................................................................... 37

5.5.3 HYDRo-GEOLOGY..........................................................................

37

5.5.3.1 Regional Hydro-geology ..................................................37

5.5.32 Site Hydro-geology ...................................................... 37

5.6 AIR QUALITY .............................................................. 37

5.6.1 PM, C02, NOX, SOX, CO, POP's EMISsIONs ......................................................... 37

5.6.2 BASELINE DATA ................................................................... 37

5.6.3 DUST EMISSIONS .................................................................. 3 8

5.6.4 AMBIENT AIR QUALITY ............................................................. 3 8

5.7 NOISE .................................................................... 39

5.8 FLORAL ENVIRONMENT .................................................................................40

5.8.1 NATURE RESERVES ................................................................40

5.8.2 ENDANGERED SPECIES .............................................................. 40

5.9 FAUNAL ENVIRONMENT .................................................... 41

5.9.1 ENDEMIC WILDLIFE ................................................................41

5.9.2 ExoTIC SPECIES ................................................................... 41

CHAPTER 6: ENVIRONMENT MANAGEMENT PLAN ..................................... 42

6.1 INTRODUCTION ........................................................... 42

6.2 NEGATIVE IMPACTS AT CONSTRUCTION .......................................42

6.21 BIOLOGICAL POLLUTION OF SITE...................................................... 42

6.2.1.1 Source oflmpact ....................................................... 42

62.1.2 Mitigating Measures..................................................... 43

6.2.2 ACCUMULATION OF SOLID WASTES ......................................................... 43

6.2.2.1 The Impact ........................................................... 43

6.2.2.2 Mitigating measures ........................................................... 43

6.3 NEGATIVE IMPACTS DURING OPERATION PHASE ....................................................... 44

6.3.1 ATMOSPHERIC POLLUTION BY PARTICULATE AND GASEOUS EMISSIONS ....................................................... 44

6.3.1.1 Origin of the Atmospheric Pollution ................. .......................................... 44

6.3.1.2 Impacts of CO2 Emissions ................................................. 45

6.3.1.2.1 Contribution to Global Warming .................................................. 45

6.3.1.2.2 Intensity of Impact due to C02 emissions ............................................ 46

6.3.1.2.3 Mitigating Measures ................................................................ ........................ 46

6.3.1.2.3.1 Accounting C02 emissions in Global Effect ........................................ 46

6.3.1.3 Impacts of CO Emissions .................................................. 46

6.3.1.3.1 Health Hazard due to CO emissions ................................................ 46

6.3.1.3.2 Health Hazard due to CO emissions ................................................ 47

6.3.1.3.2.1 Ambient Concentrations ................................................................ ........ ............. 47

6.3.1.3.2.2 Emission Standards ........................................................................................48

6.3.1.4 Impacts of Nitrogen Oxides emission .......................................... 48

6.3.1.4.1 Health Hazards........................................................................................................

48

6.3.1.4.2 Formation of Acid Rain (HN0 3)........................................................................ ............ 49

6.3.1.4.3 Eutrophication.........................................................................................................

49

6.3.1.4.4 The Greenhouse Effect.................................................................................................O

6.3.1.4.5 Hazards to Vegetals................................................................................................... 50

6.3.1.4.6 Intensity of Impacts................................................................................................... 50

6.3.1.4.6.1 Ambient Concentrations.......................................................................................... 50

6.3.1.4.6.2 Emission Rates ......................................................... ..................... ....................

51

6.3.1.4.7 Mitigating measures ..................................................................................................5 1

6.3.1.5 Impacts of Sulphur Oxides Emissions .................... ................................................. 52

6.3.1.5.1 Health Hazards...................... .................................................................. ............... 52

6.3.1.5.2 Formation of Acid Rain .............................................................................................. 52

6.3.1.5.3 Phytotoxic Effects on Native Vegetation and Agriculture .............. .......................................... 52

6.3.1.5.4 Intensityof Impact..................................................................................................... 52

6.3.1.5.4.1 Ambient Concentrations ......................................................................................... 52

6.3.1.5.4.2 Emission Rates.................................................................................................... 53

6.3.1.5.4 Mitigating Measures .............................................................................. ................... 53

6.3.1.6 Impact of Particulate Matter emissions ... ................................................................ 54

6.3.1.6.1 Health hazards.........................................................................................................

54

6.3.1.6.2 Visibility degradation................................................................................................. 55

6.3.1.6.3 Soiling and Wasting Effects ......................................................................................... 55

6.3.1.6.4 Intensity of Impacts................................................................................................... 55

6.3.1.6,4.1 Ambient Concentrations ......................................................................................... 55

6.3.1.6.4.2 Emission Rates.................................................................................. ................. 56

6.3.1.6.5 Mitigating measures................................................................................................... 56

6.3.1. 7 Impact ofPOP Emissions................................................................................... .56

6.3.1.7.1 NatureoflImpacts.....................................................................................................

57

6.3.1.7.1.1 Non-cancerous Effects .......................................................................................... 57

6.3.1.7.1.2 Non-cancerous Tolerable Doses................................................................................. 57

6.3.1.7.1.3 Cancerous Effects ....................... ........................................................................ 58

6.3.1.7.1.4 Cancerous Threshold Doses .......... ...... ................................................................... 58

6.3.1.7.2 Intensity of Impact from Ambient PCDD/PCDF Concentrations ................................................. 59

6.3.2 POLLUTION By EFFLUENTS FROM PROCESS.......................................................................... 59

6 3.2.1 The Impact................................................................................................. 59

6.3.2.2 Mitigating Measures ........................................................... ............................. 59

6.3.3 POLLUTION BY PROCESS AND DOMESTIC WASTES................................................................... 60

6.33.1 The Impact ................................................................................................... 60

6.3.3.2 Mitigating Measures .......................................................................... .............. 61

6.33.2.1 Fly Ash.................................................................................................................6

1

6.3.3.2.2 ag ....Slag ..............................................................................................................6 16

6.3.4 BIOLOGICAL POLLUTION OF SURFACE AND UNDERGROUND WATER ............................................. 61

6.3.4.1 Nature of the Impact......................................................................................... 61

6.3.4.2 Mlitigating Measures ....................................................................................... _62

6.3.5 NoiSE FROM CTSAV POWER PLANT.................................................................................. 62

6.3.5.1 Nature of Impact............................................................................................. 62

6.3.5.2 Intensity of Impact........................................................................................... 62

6.3.6 POLLUTION BY HYDROCARBON WASTES AND SPILLS .............................................................. 63

6.3.61 The Impact.................................................................................................... 63

63.6.2 Mitigating Measures ........................................................................................ 63

6.3.7 POLLUTION BY LOADED STORM RUNOFF............................................................................. 63

6.3.7.1 The Impact ................................................................................................... 63

6.3.7.2 Mitigating Measures ..................................................................................... ... 64

6.3.8 INCREASING OCCUPANCY OF QUAY No 1 .................................. ......................................... 64

6.3.8.1I Nature of the Impact ............................................................................. ........... 64

6.3.8.2 Mitigating Measures ............................................................................. ........... 64

6.3.9 RISKS WITH STRATEGIC COAL. STORAGE............................................................................. 65

6.3.9.1 Fire Risks....................................... .............................................................

65

6.3.9.1.1 Origin and Mechanism of the Risk.................................................................... .............. 65

6.3.9.1.2 Intensityofthe Risk ................................................................................................... 65

6.3.9.1.3 Mitigating Measures.................................................................................................. 65

(i) Stock Temperature Monitoring.....................................................6(ii) Putting out Col fires...................................

....................... 66

6.3.10 EXTRA DEMAND ON PUBLIC UTILITIES AND INFRASTRUCTURE ................................................ 66

6.3.10.1I Impact on CWA ........................ ..................................................................... 66

6.3.10.2 Impact on CEB .............................................................................. ..... 66

6.3.11 IMPACT ON PUBLIC ROAD INFRASTRUCTURE ............................................................................................. 67

6.3.11.1 Origin and Mechanism of the Impact ......................................................... 67

6.3.11.2 Intensity of the Impacts..................................... . ........... 67

6.3.12 IMPACTS OF 66KV TRANSMISSION LINE TO UNION VALE ....................................... 67

6.3.12.1 Origin and Mechanism of the Impact ..........................................67

6.3.13.1.1 Health Hazards ...........................................................68

6.3.13.1.2 Corona effect ....................................................................68

6.3.13.2 Probability and Magnitude of the Impact ....................................... 68

63.13.3 Mitigating Measures..................................................... 69

6.3.13.4 Impacts during Installation of the transmission line ................................ 69

6.4 POSITIVE ECONOMIC IMPACTS ........................................... 70

6.4.1 CREATION OF DIRECT NEW JOBS ............................................ ............ 70

6.4.1.1 At Construction Phase ..................................................................70

6.4.1.2 At Operation Phase ....................................................................70

6.4.1.1 Generation of Indirect New Jobs ............................................. 70

6.4.2 AVOIDED INVESTMENT COSTS TO CEB .............................................70

CHAPTER 7: ENVIRONMENT MONITORING PLAN ....................................... 71

7.1 THE ENVIRONMENTAL MONITORING PLAN ..................................... 71

7.2 EMP AT CONSTRUCTION PHASE .............................................. 71

7.3 EMP AT OPERATION PHASE.................................................. 71

7.4 DEVELOPMENT OF CONTINGENCY PLANS ...................................... 71

CHAPTER 8: CONCLUSIONS ........................................................77

APPENDIX A - SITE OWNERSHIP ....................................................79

APPENDIX B - AMBIENT AIR QUALITY MODELLING .................................... 80

APPENDIX C - COAL CHARACTERISTICS ............................................. 81

APPENDIX D - ESTIMATES OF CANE CULTIVATION ..................................... 82

APPENDIX E - WATER RESOURCES ANALYSIS ......................................... 83

APPENDIX F - SEPTIC TANK & LEACHING FIELD ....................................... 84

APPENDIX G - WIND ROSES AT PLASANCE ........................................... 85

APPENDIX H - GASEOUS EMISSIONS FROM BAGASSE ................................... 86

Compagnie Thermique de Savannah

Operation of a dual coal/bagasse-fired Power Plantat Savannah


Chapter 1: Project Background

1.1 Project OutlineCompagnie Thermique de Savannah (hereinafter referred to as CTSav), a public liability societe

duly registered in Mauritius, in response to a Public Tender, submitted an offer based on:

. the implementation and operation of a dual coal/bagasse-fired steam power plant at La

Barraque/Savannah, featuring two 185 t/h boiler and turbo-alternator units, 83.OMWE on

aggregate capacity* the setting up of a strategic storage of 19 000 tons of coal'

• the construction of a 66kV link over approximately 5.0 km between the proposed power station

and Union Vale

The Tender of SUDS has been retained.

1.2 Project Justification

1.2.1 Need for increased Generating Capacity requirements

Reference is made to the Integrated Electricity Plan 2003-2012 recently released on the web by

the Central Electricity Board (CEB). The IEP presents generating planning based upon static,

deterministic decision criteria, with the provision of reserves higher than those accepted elsewhere,

to account for the absence of supply from neighbouring jurisdictions. These reserves will include:

. Spinning Reserves, for instantaneous matching of generation exactly to any rise or fall in

demand at all times of the day and the night

• System Reserves, to meet peak demand under an rN-2 criterion', i.e. in the advent of scheduled

outage and/or failure to the largest and or next largest generating unit

The combination of spinning reserves and system reserves implies generation reserve margins of

the order of 20 to 25% of total effective generating capacity.

The capability of existing and committed generation resources by 2005 is described in Table 1.2.1.1

below from IEP 2003-2012. It includes the comning into service by October 2005 of the CTDS coal-

fired power plant at Union St-Aubin.

In 2006/2007, planned capacity additions will range between 64 and 96MW depending on whether

demand is low or high. By launching the CTSav power station, CEB will make sure that demand

will be met satisfactorily and may even be able to retire the old Fort-Victoria units.

According to Louis DECROP from SIDEC, this figure is based upon:

74 MW x 30 d x 24h x 0.60 (load factor) 600g/kWh = 19 180 tonnes.

Table 1.2. 1.1: Capability of Existing and Committed Generation Resources by 2005

Effective Capacity Capability

Crop Season Intercrop Season (GWh)

Existing HydroCEB 27.0 37.0 85

IPPs 0.3 0.3 0.4

Sub-total 27.3 37.3 85.4

Existing ThermalCEB 302 302 1 405

IPP's 117 111 810

Sub-Total 419 413 2 215

Committed New ResourcesIPPs 30 30 200

Sub-Total 30 30 200

TOTAL 476.3 480.3 2 500.4

1.2.2 Priority to Renewable Generation Technologies

Biomass, more famniliarly bagasse in Mauritius, is available recurrently during the cane crop season.

But the availability of this renewable source of energy is dependent upon many factors such as:

* climatic conditions, as rainfall is required to satisfy the water requirements of the crops for

satisfactory yields* extent of cultivated areas, a parameter that tends to decrease slowly but constantly

* centralisation of factories with more efficient use of bagasse to generate exportable energy

Savannah is well situated not only for good cane yields, but also in the prospect of the centralisation

process, with the expected closing down of Riche-en-Eau and Mon Desert - Mon Tr6sor sugar

factories, meaning considerable extra crushing and bagasse.

1.2.3 Enhancing the role of Independent Power Producers (IPPs)

The emergence of IPPs, since 1957, has been of tremendous assistance to CEB, not only in terms of

avoiding the Government high financial burden associated with the implementation of generating

plant, but also, because of the dispersed locations of the IPPs, in relieving pressure on the

transmission system.

The CTSav power plant is in line with the IPP philosophy adopted by CEB.

1.3 Legal and Institutional Framework

The implementation of the CTSav Project will be framed by the following legal, regulatory and

institutional procedures.

1.3.1 Ministry of Public Utilities

1.3.1.1 Power Purchase AgreementThe Power Purchase Agreement (PPA), which governs the terms and conditions under which

Central Electricity Board will purchase power from CTSav and eventually acquire the power plant.,

has been finalized and signed on the 18 February 2005.

1.3.1.2 Commercial Operation Date (COD)

Initially set at June 2007.

1.3.2 Ministry of Environment

The Project falls under Part B - Item 40 Power Station- of the First Schedule - Undertakings

requiring an Environmental Impact Assessment - of the Environmental Protection Act (2002).

1.3.2.1 Emission, Effluent Discharge and Noise Standards

The following Regulations and Guidelines accompany the Law and are relevant to the operation of

the Project:. Air Emission Standards (1998) proposed for Mauritius. They are supplemented wherever

necessary by World Bank Environmental Guidelines.* Effluent Discharge Standards2

* Noise Emission Standards, as per Government Notice 17 of 1997

1.3.2.2 Persistent Organic Pollutant (POPs) Emissions

POPs, namely Dioxins, emission sources, and PCB (polychlorinated biphenyls)-containing

equipment are inventoried under the Stockholm Convention of which the Government of Mauritius

is a signatory. One of the duties of the Government under this convention is to identify and phase

out POPs sources and safely manage the PCBs.

1.3.2.3 AshesAshes, which are a maj or Coal Combustion Product, are not governed by any regulations or

guidelines and reference will be made to the following decree published in the Journal Officiel de la

Republique Francaise No 93 20thApril 2002:* Ddcret no 2002-540 du 18 Avril 2002 relatif a la Classification des Dechets

1.3.3 Ministry of AgricultureThe implantation of the CTSav Project at Savannah SE is subject to a Land Conversion Permit

issued by the Ministry of Agriculture.

2 Regulations made by the Minister under Sections 34 and 74 of the Environment Protection Act 1991

1.3.4 Ministry of Housing & Lands

The implantation of the CTSav Project at Savannah SE is subject to the following clearances as

described below.

1.3.4.1 Town & Country Planning

With reference to the Grand-Port & Savane District Outline the Site lies within an agricultural zone

and the implementation of the CTSav dual bagasse/coal-fired power station is conditional upon the

granting of a Re-zoning Permit from the Town & Country Planning Board.

1.3.4.2 National Physical Development Plan

Reference is made to the following policies; inter alia, of the newly issued NPDP3:

1.3.4.2.1 Policy El

Sites for New Power Stations: Sites for new power stations need to be identified in revised Local

Plans and protected from development.

In respect of buffer zones for bad neighbour developments, reference is also made to the following

policies:

1.3.4.2.2 Policy ST3

Sites for Buffer Zones around Bad Neighbour Developments: In considering the location of bad

neighbourhood developments, buffer zones up to lkm from sensitive land uses should be identified

in revised Local Maps.

The justification mentions for such buffers, refers specifically to sewage treatment works, landfill

sites, civic amenities and major scrap yards as constituting 'bad neighbour' development for

environmental and social reasons.

1.3.4.2.3 Policy AG3

Agricultural Land Needed for National Strategic Projects: with regard to the release and

conversion (by the Ministry of Agriculture) of sites on land of high/moderate suitability for

agriculture, needed solely for specific projects of national importance (and for which no alternative

sites are available) ...

3 Goveniment of Mauritius - National Physical Development Plan. Volume 1: Development Strategy and Policies.

November 2002. HALCROW Group.


at Savannah


Chapter 2: Project Promoters & Organisation

2.1 Centrale Thermique de Savannah

2.1.1 The Project VehicleThe Project Vehicle is Companie Thermique de Savannah (CTSav) a Public Liability Companylimited by shares and incorporated in Mauritius on the 18 February 2005.

The Memorandum and Articles of Association have been drawn up by Me Hugues MAIGROT aNotary Public of the City of Port-Louis.

The Registered Office of CTSav is situated at 7 th Floor, Anglo Mauritius House, Adolphe dePlevitz Street, Port Louis.

The objects for which the Company has been established are inter alia to produce and sellelectricity and power.

2.1.2 ShareholdingThe co-proponents of the Project who have entered into. a Project Development Agreement (PDA)for that purpose, are:* Compagnie Energie Savannah Ltee (CESL), Mauritius, regrouping the so-called 'growing

companies', nemely: Cie de Beau-Vallon Ltee, MT-MD Ltd, Union-Cascade, Bel-Air* Sugar Investment Trust (SIT), Mauritius* SECHILIENNE-SIDEC (SIDEC), France, a French-registered company, experienced in the

design, implementation and operation of similar power plants world-wide, and who will providethe necessary technical assistance to operate the power plant in conformity with the provisionsof the PPA

2.2 Procurement Services

2.2.1 The Dual Coal/Bagasse-fired Steam Power Plant

The dual coal/bagasse-fired steam plant will consist of:* two steam boilers equipped with stoker-spreader furnace supplied by ALSTOM Australia

2.2.2 The Turbo-Alternator Sets

Each of the two turbo-alternator sets will consist of: v

* The turbine, of the multistage condensing type, supplied by THERMODYN* The alternator supplied by JEUMONT SCHNEIDER

2.2.3 The Power Transmission Line

The Transmission line will be supplied and installed by the EPC contractor, SOTRAMON Ltd.

2.3 Engineering ServicesEngineering Services will be provided by:

SECCHILIENNE- SIDEC, acting as owner's engineer during the construction, and as major

shareholder of CTSav company in charge of the power plant operations.. SOTRAMON, acting as Engineering Construction Procurement contractor, in charge of

dimensioning, procuring, assembling and commissioning the power plant.. SIGMA - Ove Arup & Partners in association with Dr. Alan SAMSOON, for the

environmental engineering services

2.4 Staffing of the Power Plant

The technical team in charge of the operation of the Power Plant will comprise, inter alia:

• the Plant Manager, also the official contact person with CEB* the Production Engineer (PE)* the Maintenance Manager (MM)

The PE will supervise:* Operators working in shifts. A team of three operators, consisting of a Shift Supervisor, a Plant

Operator and a Rover, as well as a Scraper Operator during the crop season, will be present at all

time in the power plant.* the Laboratory attendant in charge of the control of the 'chemical' performance parameters

The MM will supervise:* the team of mechanics consisting of a Mechanical Engineer, his administrative assistants an a

group of 4 mechanics* the team of electricians comprising an electrical engineer, his administrative assistants end a

team of electrical technicians

The technical staff enumerated in the foregoing, will be recruited at an early stage in order to

participate in the implementation, assembly and commissioning of the Plant so that they may

acquire an intimate knowledge of the Plant and of its operation.

2.5 Plant Construction Time-schedule

The COD having been stipulated in the PPA, the construction, assembly, commissioning and

handing over are scheduled as follows, re the official 'go-ahead'.

Table 2.5.1: Schedule of Power Plant Construction Operations

MONTHS

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Signature of EPC =-

Fowudation kk (rks

Ercetion of Boilers

Turbo altermators

T ransformners6tN. lineStart-up TestsCOD


at Savannah


Chapter 3: Detailed Project Description

3.1 The Power Plant ConfigurationThe Power Plant will be configured as described hereunder so as to supply the National Grid as per

the conditions set out in the PPA:* Two dual coal/bagasse furnaces* Two boilers producing superheated steam at specified pressure 82 bars and temperature 525°C

* Two extraction turbo-alternator sets with condenser and cooling tower* The switch gear interfacing the Plant to the National Grid

* A strategic coal storage of 19 000 tons of coal* A coal reception platform, conditioning plant and day storage v

* A bagasse conveyor from the sugar factory to the Plant bagasse hoppers* A steam main from the Power Station to the sugar boiling house

The Plant will deliver power to the National Grid via an approximately 5.0 km 66kV transmission

line from La Baraque to Union Vale, which forms part of the Project.

3.2 Project Site

3.2.1 Location and ExtentThe Project Site, as well as the 66kV link to Union Vale where the Power Plant will deliver to the

National Grid, is shown in Figure 3.2.1.1, reproduced from the Ordinance Survey Regional Map of

Mauritius

The specific site survey has been carried out by tric DOGER de SPIEVILLE of S.D.D.S Sworn

Land Surveyors, see plan in Figure 3.2.1.2, which shows the boundaries, in conformity with Clause

18 (1) (c) (ii) of the EP Act 2002.

The Site has an extent of 4.688ha. The footprints of the various components of the power plant are

shown in Figure 3.2.1.3.

3.2.2 Justification of Choice of SiteThe Project Site, although it appears at first sight to be quite remote from the Coal Terminal at Port-

Louis Harbour, offers:• proximity to a 66kV transmission line along a free corridor (estate road)* availability of process water as will be discussed below* availability of bagasse biomass as Savannah SE becomes the 'centralised' or major sugar factory

of the South when Mon Desert - Mon Tresor and Riche-en-Eau factories close down

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COMPAGNIE THERIMIQUE-a SurjrJiAe;

DE SAVANNAH Ltd.Construction & Operation of a

83 MW Coal/Bagasse-Fired Power Plantat Savannah

Figure 3.2.1.1 - Location Plan of Plant

I~Scale 1:25 000Dae Amue 2005

Job No. 2436

; fS.l.G.M.A. - Ove Arup & PartnersAssociated Consulting Engineers

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COMPAGNIE THEMIUE

SAVANNAH S.E DE SAVANNAH Ltd.

Relev6 topographique d'un terrain devant servir i la Constmetion & Operation of a83 M Co/BeWe-FredPower Plant

construction d'une central thermique at Sava8ah

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Construcdon & Operation of a83 MW Coal/Bagasse-Fired Power Plant

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3.2.3 OwnershipThe Site described above has been excised from the plot of land of 1074 A 73p situated at La

Baraque and belonging to the Savannah sugar estates as per TV 487 No 48.

The ownership is authenticated by the certificate drawn for that purpose, by notary public Me Jean

Pierre MONTOCCHIO as reproduced in Appendix A.

The certificate also states that the said land has been released by the owner to CTSav for the

implementation of the Power Plant. In conformity with Clause 18 (1) (c) (iv) of the EP Act 2002.

3.2.4 Present OccupancyThe land dedicated to the Project is presently in zone as Agricultural Land and is under cane

cultivation. In conformity with the provisions of local regulations, the land to be detached to CTSav

must be the object of:a Land Conversion Permit issued by the Ministry of Agriculture

a Re-zoning Certificate, issued by the Town & Country Planning of the Ministry of Housing &

Land

The dossiers have been submitted accordingly.

3.3 Furnaces and Boilers

3.3.1 The FurnacesThe type of furnace envisaged is a classical spreader-stoker, mobile-grate furnace, manufactured

ALSTOM Australia. The design and performance characteristics of the dual combustible furnaces

(2Nos) for each furnace using coal or bagasse only are as follows:

Coal Bagasse

Average CV (kJ/kg) 25 500 7 750

Maximum Burning Rate (kg/h) 18 760 78 800

Combustion air Inflow Rate at MBR (kg/h) 202 400 296 000

Flue gas emission rate at MBR (Nm3/h) 164 360 304 270

ditto (kg/h) 217 900 372 700

Annual Average Burning Rate (kg/h) 14 108 50 000

Flue gas temperature (CC) 135 160

Flue gas velocity at exhaust temperature (m/s) 20.3 20.3

Stack Diameter (m) 2.9 2.9

Duration of firing (hours per annum) 4400 3 600

* The Stack height: 56m nominally, as proposed initially by the Promoter.

* Stack diameter: two ducts of 2.90 m diameter each.

* Additional Blowers will be used when burning of coal to obtain flue gas exhaust velocities of not

less than 20m/s

3.3.2 The BoilersThe design and performance characteristics of each of the boilers using coal or bagasse are:

Coal BagasseEfficiency optimisation steam rate (ton/h) 140 175Maximum continuous running steam rate (ton/h) 150 185Peak operation steam rate (ton/h) 150 185Steam Pressure (Bar Abs) 82 82Nominal Temperature at Turbine inlet (°C) 520 520Superheating Level (°C) from 70% MCR 525Superheating Level (°C) from 50% MCR 525

3.4 Turbo-alternator Sets

3.4.1 Performance CharacteristicsThe generator/s driven by the steam turbine/s will have the following output characteristics:• Gross Output: 83 MWE* Net exportable output: 74MWE (in conformity with ISO 8 528 - 1) during the intercrop season

and 75MWE during the crop season of which 9,5MWE to the sugar factory and 65,5 MWE to the vnational grid

* Voltage: 11 kV* Frequency: 50Hz ± 5%• Operational availability as per PPA.

3.4.2 SwitchgearThe switchgear will be designed, in conformity with the relevant IEC standards, for outdoorlocation and capable of continuous operation under the prevailing Site climatic conditions. Theoutdoor switchyard and equipment (circuit breakers, disconnectors, lightning arrestors, currenttransformers, metering,) to be connected to the National Grid, and details of the Transformer are asfollows:* Type: Outdoor type with cooling oil conservator* Rated power: 50MVA ONAN at 35°C maximum ambient temperature• Rated Voltages: 66/1 1kV* Tap changer: ± 2x2.5% off-load type* Standards: IEC 76* Cooling: ONAN 100%

Peak power and energy dispatch to the National 66kV Grid will be governed by the terms of thePPA.

3.4.3 Plant DC SystemThe DC system supplies DC-power to Plant Control Room, namely for dispatch automation,synchronization, generator protection and alarm annunciation.

This system is not dependent upon the Plant AC auxiliary voltage system to ensure a safe shutdownin case of failure of the said auxiliary voltage supply. It will consist of, inter alia:* A lead acid battery of the appropriate VDC and Ah/h ratings* A battery charger of the appropriate rating• A switchboard• A stand-by generator set to ensure continuous autonomy.

3.4.4 Plant Lubrication SystemFor the turbine shaft-line, and eventually the alternator, main recommendations for minerallubrication oil are:

Viscosity SAE 40 at 40°C 32 cStVolumetric Weight at 15°C 865kg/m3Flash point, closed > 2000CAniline point > 900 CMaxiimum Water Content: 80 ppmAir release value tp 0.2% air at 500 C 2 minSteam de-emulsion < 90 s

3.4.4.1 Used Lube Oil Collection and DisposalUsed lube oil and oily waters from the plant lubricating circuit will be stored in a storage tankprovided to that effect.

The used oil will be disposed of by combustion in the boiler furnace on Site.

3.4.5 Plant HP Hydraulic ControlThe jack actuating the steam inlet valves in the Turbines as well as the servo-jacks which operatethe inlet control valves and the extraction valves are part of a hydraulic system to which hydraulicoil is supplied at a pressure of - 120 Bar

The HP hydraulic control assembly will consist of, inter alia:. a C-steel oil tank with interior epoxy coating, equipped with level indicators, instrumentation,

valves and fittings, suitable for hydraulic quality oil* two redundant electric motor - variable displacement pump sets, operating to a maximum

discharge pressure of - 15OBar* DC accumulator for automatic pump starting. A water-oil heat exchanger with by-pass check valves and calibrated check valve in stainless

steel return pipes

3.5 Coal Supply and Management

3.5.1 Origin and Characteristics of CoalTo produce steam of the required quality and at the required rate, the furnace will consume atexpected production rate of the plant -197 996 GWhE/y -, a yearly mean value of about 125 000tons of coal per year. The furnace combustible will be coal imported from Richard's Bay 4, SouthAfrica, by the local Coal Terminal Management Co. Ltd.

The granulometry of the Coal that will be delivered on Site from the Coal Terminal in Port LouisHarbour is expected to be as follows:

Sieve (P (mm) 1 2 6 10 16 20 25 30 50 80 120 >120% smaller 7 10 15 25 42 55 68 80 100 98 99 1% average I 11 21 41 55 67 72 84 87 94 99 100 0% larger 13 25 45 65 75 85 90 93 95 100 0 0

The as-received coal must be conditioned as the coal feed to the spreader stoker must not containcoal particles >25mm in diameter.

Typical granulometry expected for coal fed to spreader stoker is as follows:

Sieve rD (mm) 1 2 6 10 15 20 25% smaller 5 10 15 25 52 80 100% average 15 25 55 80 95 98 100% larger 20 35 65 90 97 99 100

Some of the constituents, namely Moisture, Ash, Volatile Matter, Sulphur, of the coal received atthe Coal Terminal Management Co Ltd, have been analysed for all the batches received since 2000and the results are summarised in Table 3.5.1.1 below, details being in Appendix C hereto.

Table 3.5.1.1: Analysis Results for Coal received from South Africa

ANNUAL COAL ANALYSIS RESULTS

YEAR MOISTURE ASH VOL. MATTER SULPHUR NCV(%) (%) (%) (%) (%)

Max Min Max Min Max Min Max Min Max Min2004 8.8 6.6 13.3 10.5 30.4 22.5 0.86 0.39 6 138 6 0302003 7.8 5.7 14.5 12.8w 25.0 23.6 0.67 0.41 6 176 6 0732002 7.3 6.8 13.8 11.6 27.7 23.5 0.84 0.32 6 226 6 0662001 7.4 5.8 13.9 12.7 25.8 24.6 0.81 0.66 6 279 6 0442000 8.8 6.8 13.7 11.6 25.3 22.6 0.72 0.46 6 318 6005

Required 9% 14.0 10.0 26.0 22.0 0.90 0.70 6 100 6 000

4SIGMA Ove ARUP: Coal Storage in Port Louis Harbour. EIA. January 1998.

The results of Table 3.5.1.1 call for the following remarks:* The range of values is indicated: the actual statistical distribution cannot be inferred from the

'batch' results that have been communicated; no information is available as to how well the

samples analysed are representative of a batch* In general, the moisture content, ash content, sulphur content and NCV are well contained

within the initial as-received requirements set out for coal imports

• Of importance for atmospheric pollution, the S-content varies from 0.32% for a batch of 44 492

tons received in 2002 from the Anker Coast Company to a maximum of 0.86% from the same

company in 2004.

For the purpose of establishing the Thermal Efficiency, the "design" coal characteristics adopted by

the boiler manufacturers are as per Table 3.5.1.2.

Table 3.5.1.2: 'Design' Coal Characteristic

UNIT Maximum Average Minimum

Humidity (Gross) % 14 10 7

Ash (Gross) % 16 14 7

Volatile Matter (Gross) % 30 23 20

Sulphur (Gross) % 1.3 1

Swelling Index 1.5 1 0

LCV kJ/kg 29 800 25 500 23 000

For the same purposes, typical analysis of coal constituents (by weight) has been assumed as per

Table 3.5.1.3.

Table 3.5.1.3: Typical Analysis of Coal Constituents(% by weight)

Constituents UNIT Dry Basis As Fired

Carbon C % 70.50 63.85

Hydrogen H2 % 3.00 2.70

Oxygen 02 % 8.50 7.65

Nitrogen N2 % 1.50 1.35

Sulphur S % 0.50 0.45

Chlorine Cl2 % 0.20 0.18

Ash % 15.55 14.00

Moisture % - 10.00

3.5.2 Strategic Storage Facility

A strategic storage of 19 000 tons of coal representing one month's consumption, will be provided

to feed the plant in the event of prolonged shortage from the South African supplier.

The Site coal storage area required will be of the order of 7 600 m2, based upon:

Tonnage of stored coal: 19 000 tonTypical loose-density: 1 .OOt/m 3

Loose stacking heights: <4.Om

The strategic coal storage area, as described by the Proponent, will be of the totally enclosed type to

shield the coal from:. Rain, and therefore limit increased moisture and risks of spontaneous ignition, runoff, seepage

and acid and heavy metal leaching into the ground water

* Wind, and therefore, limit fugitive dust emissions

In particular the following measures will be incorporated in the construction of the strategic coal

storage:. the coal shall be laid to the stockpile in layers not thicker than 500mm and each layer will be

compacted by means of a roller* the final layer of compacted coal shall be impermeably covered by a layer of 300mm of top-soil

. the sides shall be sloped to an angle of repose of 300/400 and covered with a plastic sheeting

itself topped up with vegetated earth

3.5.3 Fighting Fires to Environment

The Proponent have made provision for the implementation of a ring main type fire fighting

network with hydrants at a distance of not more than 200 metres. The main buildings shall be

equipped with a 'piping dry riser' enabling the supply of water at all levels of these buildings.

The bagasse storage will be equipped with two hydrants located at each entrance of the store.

A water storage reservoir of 900 m3 will be provided to supply the fire-fighting system via an

electro-pump with a capacity of 180 m3/h(at 8 bars) and a diesel pump of the same capacity and

pressure as back up.

Fire and smoke detection devices will be located in sensible areas and adequate protection systems

will be installed.

3.5.4 In-situ Coal Handling at Reception

Coal will be hauled from the Coal Terminal in Port-Louis by means of Lorries and totally closed

trailers to eliminate fugitive dust, in all respect similar to those presently hauling coal to the CTBV

Power Station at Belle-Vue.

The trailers will be weighed upon arrival before discharging the coal of granulometry ranging from

0 to 100mm typically on a reception platform which will consist of:

* a coal hopper/tipper system for discharging the coal from in-coming trucks

* a conveyer to feed the coal from the hopper to the conditioning unit

The coal reception unit will be located inside a roofed and walled enclosure to abate the propagation

of airborne dust. A coal handling diagram is shown in Figure 3.5.4.1.

3.5.5 Coal Conditioning Unit

The raw coal needs to be conditioned before being fed to the furnace. The conditioning unit which

will be fed from an hopper, will consist of:

-- z= B z + -- 7

+ etal detector

Magnetic Iron COAL SILO Crusher /Screen Over band1500T_

Screw 0/25

A HOP R - . -ReceptionWeightometer -- $ Station

.I FCoal Stock 19,000 T


Construction & Operation of a83 MW Coal/Bagasse-Fired Power Plant

at SavannahFigure 3.5.4.1 - Coal Handling Diagram

Date June 2005

. a roll crusher of the toothed type, design to avoid the generation of fines (<< 5mm), with anominal crushing capacity of 45t/h, for coal granulometry ranging between 25 and 80mm

* a screen, of the double-deck type, of capacity 1 60t/h, with a first deck aperture of 80mm and a

second deck aperture of 25mm

The coal passing through the screen will have a grain size that will not exceed 25mm, as suitable for

a spreader stoker furnace.

An overhand iron magnet will be located at a convenient place along the coal conveying circuit forthe removal of iron scraps that could be present in the coal.

The unloading platform and the conditioning unit will be located inside a roofed and walled

enclosure.

The crushed and sieved coal will then be lifted by hooded conveyer belts to either the boiler day-bins, or to a reinforced concrete 1500 ton coal silo located outside the Plant.

The silo will be fitted with a screw lift that will deliver coal to a hooded conveyor belt feeding the

furnace day-hoppers of 300 ton capacity.

3.5.6 Coal Combustion Products: characteristics, handling, disposal

3.5.6.1 Coal Combustion Products

The extent to which ash and other types of coal combustion products (CCP) occur, for non-

pulverized coal for the spreader unit to be installed at Savannah should be, according to the

Designer:* Fly Ash: 20% of the 'as fired' Ash Content of the coal* Slag: 80% of the 'as fired' Ash Content of the coal

The characteristics of the CCP's and other data concerning them are tabulated below:

Table 3.5.6.1.1: Types of CCP and their Characteristics

CCP Characteristics Texture Typical weight Major constituents(%/ coal)

Fly Ash Non-combustible particulate Powdery, silt-like 3% Primary: SiO2matter removed from stack gases Secondary: A1203

Bottom Ash Material collected in dry-bottom Sand-like 0% Tertiary: Fe2O3boilers, heavier than fly ash Trace: P205, TiO2, Na20,

Slag*5 Material collected in wet-bottom Glassy, angular TcO K 20, T- S NaOboilers or cyclone units particles 12% 2 °.SO 3 .

The daily productions of CCP's can be worked out from knowledge of the weight of coal burnt at

the Plant.

5 Note: The Spreader-stoker to be installed by CTSav will be of the wet-bottom type and only slag will therefore be

produced.

3.5.6.2 Fly Ash

From the foregoing and assuming that the stack gases emitted per ton of combusted coal typically

produces about 10 000 Nm3 flue gases, the concentration of fly ash in the flue gases would be of the

order of 3gm/Nm3, which exceeds maximum permissible limits and imposes the necessity for PM

filtering. The ash handling diagram is shown in Figure 3.5.6.2. 1.

In consequence, an electrostatic precipitator will be fitted to the CTSav power plant stack to limit

PM emissions to only PM, 0 to the permissible concentrations, i.e. 150mg/Nm 3.

The analytical composition of the fly ash is typically SiO2 + A1203 < 85% by weight.

3.5.6.3 Slag

Fumace slag, of coarser granulometry, will be collected by means of a conveyor belt that will run

through a trough to quench the hot ash. After quenching, the ash will fall on to another conveyor

that will lift it to a hopper where it will fill closed containers for ultimate disposal.

The annual tonnage of slag may be inferred from the annual tonnage of coal burnt.

3.5.6.4 Flue Gases Characteristics

Flue gas emission rates are estimated hereunder for Coal (South African origin) burnt at a

maximum nominal rate of 18.76 tons/h per boiler (i.e. at 37.52 tons/h for both boilers).

Hourly, daily and annual emissions will obviously depend upon the actual operation as stipulated in

the PPA. The Proponent has submitted on average, 4400 hours per annum and the annual

atmospheric emissions will therefore be computed on that basis. But the hourly and daily averages

will have to be computed for both units under full steady load.

Table 3.5.6.4.1: Typical Flue Gas Emissions from Coal at Full Steady Load

Exhaust Components Emission Factor Activity Factor Emission for one Emission for tw4boiler (kg/h) boilers (kg/h)

TSP (with ESP) 50**mg/Nm3 164 360 Nm3 /h 8.218 16.436

PMIO (as dry filterable dust) 50mg/Nm3 164 360 Nm3/h 8.218 16.436

CO2 [email protected]%C 4 084kg/ton 18 760kg/h 76 615.840 153 231.68

CO (dry ( 15 vol% 02) 100 mg/Nm3 164 360 Nm3 /h 16.460 32 920

SO,, as SO2 <0.6% S content 1 368 mg/Nm3 164 360 Nm3 /h 225f6 450

NO, as NO2 (dry @ 15 vol% 02) 650mg/Nm3 164 360 Nm3/h 106.834 213.668

VOC 0.025kg/ton 18 760kg/h 0.469 0.938

Fluorides 0.075kg/ton 18 760kg/h 1.407 2.814

HCI 0.600kg/ton 18 760kg/h 11.256 22.512

Pb 0.00021kg/ton 18 760kg/h 0.004 0.008

PCDD & PCDF (max) 0.014 ng/Nm3 164 360 Nm3 /h 2.301x 10-9 4.602x 10-

Exhaust ias (for one boiler)- mass flow 217 900kg/h

- volume flow (0°C, 101.3kPa) 164 360Nm3 /h

- temperature (d 100 C) 135 0C

6 It is assumed that all S present in the coal is incorporated into SOx although it has been reported that about 10% of S

present in the coal re appears in the ash.

ELECTROSTATIC FiLTER

Mechunicol Duster Economser

Screw No 2 rOrr

COMPAGNIEE THIERMIQUEDE SAVANNAH Ltd.

Construction & Operation of a

83 MW Coal/Bagasse-Fired Power Plantat Savannah

CFigure 3.5.6.2.1 - Ash Handling Diagam

Dat June 2005

The following rates, communicated by the Promoter have been used to arrive at the atmosphericemission rates of Table 3.5.6.4.1, for the CTSav power plant.

Table 3.5.6.4.2: Operational and emission data communicated by the Proponent

Bagasse CoalMCR (kg/h) 156 000 37 520Full Load (MWh) 83.00 83.00Gross fuel/power ratio at MCR 1.88 kg/kWh 0.45 kg/kWhNet fuel/power ratio (from Promoter) 2.62 kg/kWh 0.63 kg/kWhStack gas emission rates (Nm3/h) 608 540 Nm3/h 328 720 Nm3/h

C02 emissions (from Promoter)C-content 24% 73.3%per kWh 2 518 gm C02/kWh 1 518 gm CO2/kWhper kg fuel 1 339 gm C02/kg 4 084 gm C02/kgper Nm3 343 gm C02/Nm3 466 gm C02/Nm3

S02 emissions (from Promoter)S-content 0.015% 0.60%per kWh 0.522 gm S02/kWh 4.88 gm S02/kWhper kg fuel 0.278 gm S02/kg*7 10.8 gm S02/kgper Nm3 0.0777 gm S02/Nm3 1368gm S02/Nm3

The PCDD & PCDF (Dioxine and Furane) emission rates are the maximum rates measured atCTBR, Reunion Island. Values communicated on the 25 February 2005 concerning the coal-firedoperation at CTBR are:* Minimum PCDD & PCDF: 0.001ng/m3; Maximum PCDD & PCDF: 0.014ng/m3.

The maximum value has been retained for the purpose of the EIA.

Expressed as per Nm3, the pollutant concentrations in the flues gases from the CTSav power plant,when fired by coal, are as per Table 3.5.6.4.3.

Table 3.5.6.4.3: Typical Flue Gas Emissions per Nm 3 (for coal)

POLLUTANTS Emission Rates

PM 50mg/Nm3

NOx 650mg/Nm 3

CO2 466g/Nm3

CO*" 100 mg/Nm3

SOx 1 368mg/Nm3

PCDD/PCDF 0.0 14 ng/Nm3

7By stoichiometry,

8 The actual rate of emission of CO will depend upon the efficiency of the combustion process and of the injection ofadequate secondary and tertiary combustion air into the furnace.

These emission rates will be used for the computation of the atmospheric dispersion of pollutants bymeans of US EPA approved numerical model ISCST3 pending the release of the more recentAERMOD code. With all the usual reserves that must be made concerning the accuracy of theresults.

3.6 Bagasse Supply and Management

3.6.1 Origin of BagasseIn accordance with the provisions of the PPA, the Savannah sugar mill will guarantee the crushingof an annual cane supply of 1 200 000 tons. At horizon 2007, when the neighbouring sugar mills ofRiche-en-Eau and Mon Tresor - Mon Desert (MT-MD) will have closed down, all the canes fromthese factory areas will be milled by Savannah.

Estimates (details in Appendix D hereto) of cane cultivation, harvest and yields within the factoryareas centralised of SUDS, indicate an average annual cane tonnage of 1 169 313. To meet the I200 000 tons per annum target set out in the PPA, SUDS will import the difference from the UnionSt-Aubin factory area whenever necessary.

3.6.2 Characteristics of BagasseThe physical and chemical characteristics of Bagasse from Savannah mill are as per Table 3.6.2.1below. These characteristic values have been used for design purposes.

Table 3.6.2.1: Characteristics of Bagasse from the Savannah Mill

UNITS VALUESCarbon % 24.95Hydrogen % 3.09Sulphur % 0.01Nitrogen % 0.14Oxygen % 21.85Moisture % 48 - 52Ash % 1.97

Sugar content (average) % 1.50Gross Calorific Value kJ/kg 9 772Net Calorific Value kJ/kg 7 750Bulk density kg/m3 100-150

3.6.3 Bagasse Combustion Products: characteristics, handling, disposal

3.6.3.1 Bagasse Combustion ProductsThe extent to which ash and other types of bagasse combustion products (BCP) occur, should be,according to the Designer:* Total Fly Ash: -5.25% by weight of dry bagasse* Bottom Ash: - 0.39% by weight of dry bagasse

The characteristics of the BCP's and other data concerning them are tabulated below:

Table 3.6.3.1.1: Types of BCP and their Characteristics

CCP Characteristics Texture Typical weight Major constituents(% dry baasse)Fly Ash Non-combustible particulate Powdery, silt-like 5.25% Primary: SiO 2_ matter removed from stack gases Secondary: A1203Bottom Ash Material collected in dry-bottom Sand-like 0.39% Tertiary: Fe2O3boilers, heavier than fly ash ________Trace: P205, TiO,, Na 2O,Slag* Material collected in wet-bottom Glassy, angular 0% K20, CaO, MgO, MnO3,

boilers or cyclone units particles ... , aO,4

A bagasse handling diagram is shown in Figure 3.6.3.1.1

3.6.3.2 Fly AshFrom the foregoing for one boiler using bagasse as combustible, the following data are pertinent:

the stack gas emission rate will be 319 000 Nm3/hthe ESP controlled PM1O emission rate will be 35mg/Nm 3 /hthe gross fly ash emission rate will be 2.7% by weight on wet bagasse

* the gross wet bagasse burning rate will be 78 800kg/h

The fly ash trapped at the ESP will therefore represent about 50 794kg/d.

Hence for the two boilers, the total fly ash trapped at the ESP is 101 588kg/d.

The analytical composition of the fly ash is typically SiO2 + A1203 + Fe203.

At present, the major part of the fly ash is intercepted by the wet scrubber that equips the stack andis unloaded in the cane fields.

3.6.3.3 Bottom AshBoiler bottom ash, of coarser granulometry, will be collected by means of a conveyor belt that willrun through a trough to quench the hot ash. After quenching, the ash will fall on to anotherconveyor that will lift it to a hopper where it will fill closed containers for ultimate disposal.

The daily tonnage of boiler bottom ash may be inferred from the tonnage of bagasse burnt in thefuture plant, namely 78 800 kg/h and the monitoring carried out at the existing Savannah sugarfactory, namely about 0.4% by weight of dry bagasse or 0.2% on wet bagasse.

The daily production rate of boiler bottom ash will therefore be of the order of 7 564 kg/d for bothboilers.

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3.6.3.4 Flue Gases CharacteristicsFlue gas emission rates are estimated hereunder for cane bagasse burnt at a maximum nominal rateof 78.8 tons/h for one boiler (i.e. 1 57.6tons for 2 boilers).

Daily and annual emissions will obviously depend upon the actual operation as stipulated in thePPA. The Proponent has submitted on average, 3 600 hours per annum and the annual atmosphericemissions will therefore be computed on that basis.

Table 3.6.3.4.1: Typical Flue Gas Emissions from Bagasse at Full Steady Load.

Exhaust Components Emission Factor Activity Factor Emission for one Emission for 2boiler (kg/h) boilers (kg/h)TSP (with ESP) 100 mg/Nm3 304 270Nm3/h 30.427 60.854PM1 O (as dry filterable dust) 100 mg/Nm 3 304 270Nm3/h 30.427 60.854CO2 (@ 25%C) 343 gm/Nm 3 304 270Nm3 /h 104 364.610 208 729.22CO (dry @ 15 vol% 02) 4.8 mg/ Nm3 304 270Nm3 /h 1 461 2 922SOX as SO2 <0.0 15% S content 77.69 mg/Nm3 304 270Nm3 /h 23.64 47.28NO, as NO 2 (dry @ 15 Vol% 02) 306 mg/Nm 3 304 270Nm3 /h 93.1069 186.214VOC 476 mg/ Nm3 304 270Nm3 /h 144.835 289.67Fluorides

HCI 0.547 mg/ Nm3 304 270Nm3 /h 0.166 0.332Pb 0.003 mg/Nm3 304 270Nm3 /h 0.912x 10-3 1.824x 10-3PCDD/PCDF 0.10 ng/Nm3 304 270 Nm 3/h 0.030 x 10-9 0.060 x 10i9Exhaust aas (for one boiler)- mass flow 372 700kg/h- volume flow (0°C, 101.3kPa) 304 270Nm3 /h- temperature (: 1 0° C) 1600C

The PCDD & PCDF (Dioxine and Furane) emission rates are the maximum rates measured atCTBR, Rdunion Island. Values communicated on the 25 February 2005 concerning the bagasse-fired operation at CTBR are: Minimum PCDD & PCDF: 0.004ng/m3; Maximum PCDD & PCDF:0.01 Ong/m3.

The maximum value has been retained for the purpose of the EIA.

Expressed as per Nm3 , the pollutant concentrations in the flues gases from the CTSav power plantare as per Table 3.5.6.4.2.Table 3.5.6.4.2: Typical Flue Gas Emissions per Nm 3

POLLUTANTS Emission RatesPM 100 mg/Nm3

NOx 306 mg/Nm3

CO2 343 gm/Nm3

CO__ _ 4.8 mg/Nm3

SO2 77.69 mg/Nm 3

PCDD/PCDF 0.10 ng/Nm3

9 The actual rate of emission of CO will depend upon the efficiency of the combustion process and of the injection ofadequate secondary and tertiary combustion air into the furnace.

These emission rates will be used for the computation of the atmospheric dispersion of pollutants bymeans of US EPA approved numerical model ISCST3.

3.7 Project Infrastructure

3.7.1 Power Plant AccessAccess to the Power Plant Site will be via the paved (tarred) entrance to the Sugar Factory, off theB8 Main Road. In particular, the coal lorries from the Coal Terminal in Port-Louis Harbour willtravel along the Port-Louis / Plaine-Magnien Motorway, which they will leave at the L'Escalier-Souillac Roundabout, to follow a newly implemented road down to the junction with the B8 MainRoad.

The route of the coal lorries is shown in Figure 3.7.1.1.

3.7.2 Lorry Cleaning FacilitiesIt will be recalled that all Lorries leaving the Coal Terminal in Port-Louis'° are deemed to gothrough cleaning facilities, which consist of a water-filled dip of sufficient dimensions to ensure theremoval of coal particles adhering to the wheels.

A stretch of paved road is available between the vehicle cleaning pit and the public highway, so thatremaining debris are dropped over the compound.

Similar provisions will be made on Site to prevent contamination of Public Roads with coal dust.

3.7.3 Peripheral DrainA peripheral drain will be constructed around the coal unloading and processing facilities. Thisdrain will receive rain-induced run-offs or plant floor washings contaminated with coal dust andspilled hydrocarbons (lube oils, hydraulic fluid,). It will be of the concrete-type, to an appropriatewidth and depth, which will:* incorporate a hydrocarbon separator* allow a Backhoe-type of loader to clean it free, from time to time, of accumulated coal particles

and dust* provide a buffer storage to rainfall of 20 years return period (about 57 mrn/h)* flow into sedimentation ponds where it may be treated before re-use or safe discharge into the

environment

3.7.4 Settling PondsSurface run off and plant floor washings collected by the peripheral drain will be sent to settlingponds after going through the hydrocarbon separator. The settling ponds will be provided in aconfiguration to remove coal particles and other suspended solids from the water before dischargeor re-use.

'° SIGMA Ove ARUP & Partners: Coal Storage in Port-Louis Harbour. EIA January 1998.

COMPAGNIE THERMIQUE DE SAVANNAH Ltd.Construction & Operation of a 83 MW Coal/Bagasse-Fired Power Plantat Savannah

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3.8 Project Water RequirementsProject water demand will arise for Power Plant process and Staff pot.

3.8.1 CTSav Process Water RequirementsProcess water requirements and source of supply are detailed hereun

Table 3.8.1.1: Process Water Requirements and S

PROCESS WATER In-flow Rate SOURCE of SUPrL XCooling Tower evaporation make-up water 220m3 /h Savannah & MT-MDBoiler blow-down make-up water Sm3/h - ditto -Demineralization plant regeneration water 3m3/h - ditto -

3

Cooling Tower blow-down make-up water 70m lh - ditto -TOTAL In-flow Rate 300 m /h

Process water requirements (300 m3/h or 84 t/s or 3 ft3/s) will be partly met by water from thewater rights accruing to Savannah SE on the neighbouring water courses, and MTMD. Reference ismade to the water resources analysis detailed in Appendix E hereto.

3.8.2 Potable Water RequirementsThe Central Water Authority, responsible for the production, distribution and sales of potable waterin the district, will ensure the supply of potable water of the order of 2-3 m3/d.

3.9 Waste Water from CTSav

3.9.1 Power Station Process Effluent

3.9.1.1 Origin and Production RatesWith reference to Flow Diagram in Figure 3.9.1.1.1 the sources of process effluents from theCTSav Power Station and their indicative rates of generation will, a priori, be as detailed below

Table 3.9.1.1.1: Rates of Production of Effluents from Power Station

PROCESS WATER In-flow Rate POLLUTIONBackwash Filters

1.7 m3/h Suspended matterBoiler blow-down

5-6 mr/h ChemicalDemineralization plant regeneration water 1-2 m3/h ChemicalCooling Tower blow-down through coal & ash unit 70 0 Mr/h Chemical & suspended matterDemineralisation Plant 1-2 m3/h Chemical

TOTAL Rate 78 - 87 m3/h Chemical & suspended matter

The flows stated in Table 3.9.1. 1.1 are indicative of maximum flows, but will understandably varyaccording to:* rainfall regime* actual level of power generation which as per PPA will vary with CEB consumer call

3.9.1.2 Quality of Process Effluent ComponentsEach of the components of the Process effluents will have its own physico-chemical composition.However, as can be appraised from the effluent flow diagram of Figure 3.9.1.1.1, all thesecomponents will merge into a single flux as is presently the case at Centrale Thermique de Belle-Vue (CTBV), which is also a coal cum bagasse fired power plant of 60MWE.

It appears convenient therefore to refer to the results of the physico-chemical analysis of the finaleffluents at CBV, in Table 3.9.1.2.1, data communicated by the Proponent.

Table 3.9.1.2.1: Quality of Effluents

Physico-Chemical Composition UNITS EFuentspH

9.49P.Free Alkalinity 30TDS

mle 479Colour Pt.Co 149Chemical Oxygen Demand mg/l traceConductivity

jS/cm 633Chloride mg/e 99.1Total Suspended Solids mg/C 20

Reactive Phosphorous mg/C 2.91Sulphates

mg/C 41Nitrates / Nitrogen mg1e 2.5Total Chromium mg// NilHexavalent Chromium mg/C NilAnionic Detergents mg/COil in water mg/e NilNitrite

mg/t NilAluminium mg/C NilCopper mglf NilNickel mg/C NilIron mgl/ NilZinc mg/C 0.01

Temperature _ CTurbidity

NTU 23Phosphate mg/C

3.9.1.3 Disposal of Power Station Process EffluentThe process effluents will be disposed of as irrigation water injected in the Savannah S.E. irrigationnetwork, via a settling tank, where all suspended solids will be retrieved after settling.

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3.9.2 Domestic Effluents

3.9.2.1 Quality and Rate of ProductionThe domestic effluents will originate from the use of the potable water by the personnel employedin the power plant.

The quality of the effluents is detailed in Table 3.9.2.1.1. The production rate may not exceed 2 to3m3/d.

3.9.2.2 Treatment and DisposalThe treatment process proposed is a septic tank for 48h retention and a leaching field as detailed inAppendix G hereto.

3.10 Generation of Process Wastes3.10.1 Hydrocarbon Wastes

3.10.1.1 Production RatesOnly small quantities of hydrocarbon wastes can be expected, namely:- Used lube oil: 20m 3p. a.

- Hydraulic fluid: 1 m3 p. a.

3.10.1.2 DisposalThey will be collected and stored in closed containers in waiting for burning on the site in the boilerfurnace.

3.10.2 Solid Wastes

3.10.2.1 Fly Ash

3.10.2.1.1 Production RateFly ash production is estimated below in function of production rates and combustible tonnagedescribed in the foregoing.

Combustible Tons/year Fly Ash rate TotalCoal 165 088 - 3.0% by weight 4 953 t/yearBagasse (wet) 567 360 - 2.7% by weight 15 319 t/yearTOTAL Fly Ash 20 272 t/year

3.10.2.1.2 Disposal of Fly AshFlay ash can be conveniently and economically disposed of as a supplement to Portland cement inconcrete batching. This may result from the physical and chemical characteristics, added to greaterresistance to chemical attacks, and in improved workability.

The re-cycling of fly ash confers economic value to that by-product that could be commerciallycompetitive in uses ranging from highway/civil engineering applications, to agriculturalapplications.

3.10.2.2 Slag

3.10.2.2.1 Production RateSlag production rate can be estimated at about 1 1% by weight on coal.So that - 18 160 tons can be expected per year.

3.10.2.2.2 Disposal of SlagSlag can be conveniently and economically disposed of in highway/civil engineering applicationsdue to its physical and chemical characteristics and resistance to chemical attacks.The above remarks made above for fly ash also apply for slag.

3.10.2.3 Boiler Bottom AshBoiler bottom ash production is estimated below in function of production rates and bagassetonnage described in the foregoing.

Combustible Tons/year Bottom Ash rate Total

Bagasse (wet) 567 360 - 0.2% by weight 1 135 t/yearTOTAL BottomAsh 1 135 t/year


at SavannahEnvironmental Impact Assessment

Chapter 4: Built Environment of the Project

4.1 Demography

4.1.1 GeneralThe population of Mauritius, according to the Ministry of Economic Planning and Development(MEPD), was estimated at 1 077 946 in June 1994. Salient features of the Mauritius Demographyare:

a consistent decline in growth rate from 3.12% p.a. in the 1952-1962 inter-censal period, toabout 1% at present and was expected to grow at 1.13% p.a. to reach 1 140 000 in 1999(MEPD)* a Gross Reproduction Rate (GRR) that has dropped from 1.72 in 1972 to 1.00 in 19871! and isexpected to remain at about 1. 1 up to 2000 (MEPD)* a sex composition of the population, that, from a slight excess of males over females in 1972,has reversed in 1983, to reach almost equality in 1994

4.1.2 Regional Settlement & PopulationThe resident population distribution around the Project Site, as it was in 1991 according to theCensus, is given in Table 4.1.2.1 hereunder. The present 2002 resident populations must beestimated using the growth rates stated above.

Table 4.1.2.1: Population and dwelling distribution in the vicinity of the Project SiteLOCALITIES Population Households Housing Units LocationSouillac VCA 3 591 873 839Riviere-des Anguilles VCA 8 180 1 907 1 693L'Escalier VCA 3 462 713 624 1.0 km due WCamp Diable VCA 3 599 736 619 5.0 km due WMare Tabac VCA 2 226 432 391 5.5 km due NWTrois Boutiques VCA 5 190 1 098 1 043 2.5 km due NESurinam VCA 7 904 1 830 1 637Around Batimarais & Bdnares 3 182 696 671 5.0 km due WAround Bel-Air & St-Aubin 2 260 498 494Around La Baraque & Savinia 560 122 125 <1.0 km due STOTAL 29 139 6639 6 083

The largest settlement closest to the proposed power station site is L'Escalier, with a Health centre,a community Centre, mosques, temples and a church.

" National Physical Development Plan - NPDP 1988.

There is at least one major land development or morcellement that has been implemented close toSouillac after the aforesaid population census, namely:The Union S.E. morcellement, E of Souillac and due SW of the Power Plant, with 370 plotsoccupying about 48 arpents as part of the 1 200 arpents granted under the Sugar Efficiency Act

4.2 Tourism & para-touristic activitiesThe Tourism Industry, one of the major economic resources of the Island with over 600 000 arrivalseach year, is less present on the South Coast, probably too exposed to SE Trade Winds and lackingthe attractive lagoons of the W, N and E.

Development in the field of regional tourism is planned by the Bel Air - St Felix Sugar Estate,probably in terms of a Golf Course with a Golf Lodge, due W of the proposed power station.However, peripheral tourist activity activities exist in the region and would include inter alia:* The St-Aubin restaurant or table d'h6te, in the typical colonial residence of the formeradministrator of the St-Aubin Estate, and it is a 'stop' in the so-called La Route du The circuitproposed to tourists* La Vanille Crocodile Park along river Gros Ruisseau, some 7.5km due WSW of the intendedPower Plant. The Park hosts and breeds crocodiles of course (for their hide), giant Aldabratortoises, local deer and wild boars, donkeys, and other domestic species. It also hosts certainendemic floral species that are specially protected by the ownera 'La Nef Museum in memory of poet Robert Edward HART at Souillac.

4.3 Regional Public Beaches and Recreational Sites4.3.1 Public BeachesThe main proclaimed Public Beaches, are:* Le Gris-Gris public beach, immediately E of Souillac, due SSE of the Power Station* Pomponette public beach situate beyond Souillac

Other beaches, not proclaimed Public Beaches, also exist along the coast.

4.3.2 Recreational SitesThe main recreational sites are:* The Port-Souillac quays, at the estuary of River Savanne, where the sailing ships of oldpreviously used to berth, have been reinstated and host 'Le Batelage', a restaurant and receptionhall* The sports ground at Souillac

4.4 Regional Industrial Activity4.4.1 The Sugar IndustryIndustrial activity in the area is dominated by cane sugar protection, centered on La Baraque sugarfactory near which the proposed Power Station is to be implemented. Further ENE, about 5km, MonTresor-Mon Desert sugar factory (-107 t/h crushing rate) is due to cease operation in October 2002,when, as exposed in the foregoing, all the canes within the MT-MD factory area will be processedby La Baraque.

At - 9km due WSW, the Union St-Aubin sugar factory is in actual operation, having processed 421588 tons of cane in 2003 at a crushing rate of - 150t/h. Union St-Aubin sugar factoiy is notscheduled to close down, at least at short/medium term. In fact, any shortage of cane at La Baraquerelative to PPA stipulations, will be imported to La Baraque to enable CTSav to meets its bagassetargets. Seasonal atmospheric emissions from the Union St-Aubin sugar factory will have to betaken into consideration concurrently with those of the CTSav power station.The La Baraque sugar factory has the following characteristics'2:* Cane crushing rate: 144 t/h, and 447 838 tons for the 2003 crop* Crop season factory water requirements: 253m 3/h to be reduced to 153 m3/h with theimplementation of a cooling tower, from Bassin Canon (100 m3/h) and Joli-Bois (153 m3/h)* Off-crop factory water requirements: I OOm 31h estimated from Bassin Canon* Process water input: 400m3/h (dry season flows) to 600m 3/h (normal flows) based upon waterrights from rivers du Poste at Joli-Bois and La Sourdine, Tabac at Bassin Canon, St-Amand andRuisseau Vinay

* Stack height: 30m* Stack diameter: 3.65m

When the proposed power generation is implemented, La Baraque sugar factory will cease runningits bagasse-fired steam plant and will receive the necessary steam at the pressure and temperaturerequired for sugar boiling from the turbines of the CTSav power plant.

4.4.2 Power Generation at Compagnie Thermique du Sud (CTDS)CTDS is presently implementing a 34.5MW coal-fired power plant at Union St-Aubin. This powerstation has received environmental clearance and it has been the object of a detailed analysis 3.Its annual atmospheric emissions will also have to be taken into consideration concurrently withthose of the CTSav power station and the Union St-Aubin sugar factory.

12 Communicated by M R. RIVALLAND and M Guy MAUREL, of Union St-Aubin,'3 Compagnie Thermique du Sud (CTDS) Co.Ltd.: Construction & Operation of a 34.5 MWcoal-firedpowerplant atUnion St-Aubin. EIA December 2003. SIGMA - Ove Arup & Partners Consulting Engineers.

4.4.3 Poultry FarmingPoultry farms are in operation at:• Terracine, about 5.5km due W of the proposed plant* St-Aubin, about 4.25km due WNW of Site* Savannah, about 3.0km due WSW of SUDS power plant

4.4.4 Monkey BreedingA monkey breeding unit exists at Senneville, about 8Km due W of the Project Site, where monkeysare bred for exportation, under strict health constraints, for laboratory experimentation.

4.5 Historical SitesThe zone running from Blue-Bay to Baie-du-Cap, inclusive of Surinam, Souillac and Bel-Ombre isreferred to as South Coast Heritage Zone'4 and is the object of Policy TM3: South Coast HeritageZone and South West Nature Zone.

The Old French Cemetery of Souillac is undoubtedly the major historical landmark of the region.This relic of the French Presence in the Isle of France, it is already in a state in need ofmaintenance.

4.6 Public Utilities

4.6.1 Domestic Water supplyThe domestic water supply system forms part of the Southern District Water System, which is theresponsibility of the Central Water Authority.

The Site lies within the Nouvelle France / Savanne Sub-System, part of which is illustrated inFigure 4.6.1.1 hereafter. The system is headed by the Malakoff Reservoir (TWL 119.1 7m AMSL -capacity 680m3) via 225mm cast iron pipes.

4.6.2 Electricity SupplyThe supply of electricity in Mauritius is the responsibility of the Central Electricity Board (CEB).The CEB's Production, Distribution and Expansion policies are reviewed hereunder

14 Government of Mauritius, Ministry of Housing and Lands. Review of the NPDP. Drafi Final Report. Volume 1.Development Strategy and Policies. November 2002. HALCROW Group Ltd.

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4.6.2.1 Production PolicyThe CEB production expansion policy is based upon a demand forecast that is described in detail inthe CEB's Integrated Electricity Plan 2003-2012. The probable forecast elements are summarised inTable 4.6.2.1.1 below.

Table 4.6.2.1.1: Summary of Probable Forecast Elements

YEAR Gross Generation Requirements System CapacityEnergy (GWh) Growth Rate (%) Power (MW) Growth Rate (%)2002 1 715 3192007 2 254 5.6 404 4.82012 2 727 3.9 484 3.7

4.6.2.2 Power Transmission and Distribution NetworkThe existing electrical power transmission network, as in November 2003, is describedschematically in Figure 4.6.2.2.1 borrowed from the aforesaid Integrated Electricity Plan 2003-2012.

It will be up graded to cope with demand growth and the CEB's long-term network developmentplan is based upon the minimisation of transmission losses. Inasmuch as the CTSav power station isconcerned, it will deliver power via a 66kV line to Union Vale.

4.6.3 TelecommunicationsTelephone and other telecommunications services are the responsibility of Mauritius Telecom.During the recent years, Mauritius Telecom has embarked on an upgrading and extension of thetelecommnunication network throughout the island.

4.6.4 Sewer NetworksNo sewer network exists in the Project Area

4.6.5 Road InfrastructureAccess to the Power Plant Site will be off the La Baraque Road B8 as shown in Figure 4.6.5.1. TheSite enjoys a straight link with the Port Louis - Mahebourg Motorway.

4.7 Industrial Water

4.7.1 Origin of Industrial WaterIndustrial water is here meant to be irrigation water, as well as factory water deriving from waterrights accruing to Savannah SE and Mon Tresor - Mon Desert as detailed hereunder.

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COMPAGNIE TBERMIQUEDE SAVAN~NAH Ltd.

Construction & Operation of a83 MW Coal/Baasse-Fed Power Plantat Savannah

Figure 4.6.5.1 - Access to SiteSc4,ae 1:50 000

Daft June2005Job No. 2436

SIGMA - Ove Arup & PartnersAssociated Conuisng Engineer

19 Chu'h Steet- Pad Lain - Maur,lLsTel. 212 3734d 212 GM6 212 2145 Fax (230)ZD8 0375

4.7.1.1 Savannah Sugar EstateSavannah holds water rights on River du Poste, River Tabac, RiveiThese water resources of Savannah and their utilisation, are theAppendix E hereto.

During the crop season (145 days on average), priority is given~y from the aforesaid water rights.

At Savannah, irrigation water is also derived from the water righbetween the sugar cane fields and the sugar mill.

4.7.1.2 MT-MD Sugar EstateAt MTMD, the waters derived from the estate's rights on River La Chaux via Plaisance Canal aresolely used for supplying the factory during the crop season, and do not appear to be at all used forirrigation. Irrigation water for the MTMD cane fields are obtained from the local aquifer.

4.7.2 Water Resources

4.7.2.1 Water RightsWater rights are allocated to riparian owners are based on the so-called Normal Flows of the riverdraining the catchment area within which the estates belonging to the owners are situated.The division of the normal flows is via shares pro rata of the size of the estates. Savannah S.E.occupies the catchment areas of Rivers du Poste, St-Amand and Tabac, whereas, MT-MD occupiesthat of River La Chaux.

Usually, the catchments are not regulated: which means that:* the river flows are directly influenced by the rainfall regime over the catchment• dry season flows almost invariably occur from october to december, i.e. over most of the cropseason

The 'nominal' availability of water from water rights can therefore be expressed as follows:* Savannah S.E.: < 23 ft3/s or 651f/s, on aggregate off Rivers du Poste, Tabac & St-Amand* MT-MD: < IOft3/s or 283k/s, off River La Chaux via Plaisance Canal

4.7.2.2 Water Availability

4.7.2.2.1 From Savannah ResourcesThe CTSav Power Station being closely associated with the centralised La Baraque Sugar Factory,both will receive process water from Bassin Tronche itself supplied from the Savannah water rightson River du Poste.

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It is recalled that the combined water requirements of Savannalimplementation of a cooling tower to the Sugar Factory and takingft3/s from CTSav to Savannah, are:Irrigation: 15.5 ft3/sNew La Baraque Sugar Factory: 1.5 ft3/s* CTSav: 2.3 ft3/s

Total: 19.3 ft3/s

The water rights of Savannah S.E. are insufficient to fully satisfy(irrigation + sugar factory): the percentage satisfaction observed in Iof 26%, in minimum flow conditions, to 89%, in maximum flow con,Supplying the new 350TCH sugar factory and CTSav, is of course possible, but at the expense ofcane field irrigation and consequently, of cane and bagasse yields.

4.7.2.2.2 From MT-MD ResourcesThose of MT-MD, namely accruing from Plaisance Canal off River La Chaux have been reviewed.In particular, the flows of Plaisance Canal have been gauged on the 1 June 2005 at various locationsalong its course from the off-take weir on River La Chaux, to its final destination and only use,namely the MT-MD sugar factory.

On the 1 June 2005, therefore:* 0.084 m3/s (302 m3/h or 3 ft3/s) were gauged at the MT-MD factory* 0.258 m3/s (928 m3/h or 9.3 ft3/s) at the inlet works.

These observations call for the following remarks:(i) upon closing down, the MT-MD factory will no longer need the 302 m3/h it has beenreceiving so far(ii) Plaisance Canal losses are twice the CTSav water requirements

Consequently, and in particular if MT-MD relies entirely on underground water for irrigation,Plaisance Canal, either through its residual flows, or through repairs making good the considerablelosses presently incurred, can supply CTSav without prejudice to either MT-MD or Savannah. Atthe expense of appropriate transfer works from MT-MD to CTSav, of course.A detailed analysis of mean daily flows of River La Chaux at Astroea is given in Appendix E heretoand it shows that the 300m3 /h required by CTSav are almost always available.

4.7.3 Industrial Water NetworkA number of off-take dams have been erected on the aforesaid rivers at which water is diverted prorata of the homologated water rights referred to the Normal Flow.The off-takes are conveyed either by open canals or pipelines - gravity fed or pumped - to the waterright owners. Inasmuch as the La Baraque Sugar Factory is concerned, it will be supplied (300m 3/h)from the shares tapped from River du Poste and carried by a gravity pipeline to Bassin Tronche.

The MT-MD to Savanah transfer system for the supply of CTSav is not yet consolidated.The off-takes and diversion reticulations are shown in Figure 4.7.3.1.

Compagnie Thermique de SavannahOperation of a dual coal/bagasse-fired Power Plantat Savannah

Environmental Impact AssessmentChapter 5: Natural Environment

5.1 IntroductionThis Chapter reviews the natural enviromnent of the Project Site not limited to its immediatevicinity. Disturbances to the environment can be described at the extreme in terms of extinction ofspecies or populations; but broader consequences of human-induced impacts occur at the level ofecological systems and processes. Hence these impacts will be described whenever available, withmeasured baseline data, otherwise with data from numerical models. In preparing this outline,information has been drawn freely from various studies carried out in the vicinity of the Site; thesekey sources of information are noted in footnotes to the report whenever appropriate.

The Project Site will be exposed to weather conditions, namely:. rainfall which will collect on the site, to be possibly loaded with coal dust from the CoalReception Unit, and which may be acidified by NOx and SOx emissions from the Savannah,Union St-Aubin, MT-MD sugar factories during the crop season, as well as the coal-fired CTDSpower station, off crop season• wind, which may disperse atmospheric emissions of pollutants including POP's by the Project,in various directions including sensitive components of the built as well as natural environmentA description is given hereunder, of:* the climatic data on Site* the ambient noise level* the proximate and distal natural floral and faunal environment

5.2 ClimateMauritius, in virtue of its situation at latitude 200 S and its modest dimensions (60 Km NS x 45 KmEW), is submitted to a tropical ocean climate characterized by two alternating main seasons:a hot, rainy season from November to May (southern hemisphere summer)* a mild, dry season from June to October (southern hemisphere winter)

This climatic regime is heavily biased by the wind regimes and orography, which clearly sets outtwo sharply-differentiated zones:* the windward zone, to S and SE, well exposed to trade winds• the leeward zone to W, relatively well sheltered from the trade windsThe Site is directly exposed to the prevailing east to southeast trade winds.

5.2.1 RainfallA number of rain gauges exist, not only at Savannah, where the CTSav Power Station will beimplemented, but at various locations in the distal and proximal neighbourhood of Savannah, overwhich the wind-borne atmospheric emissions from the various sugar factory and CTDS and CTSavstacks will eventually propagate.

The rain gauge closest to Site would be that of Savannah itself (coded 291365), at 58.Om AMSL,for which the monthly and annual normals for the period 1951-80 are given hereunder1 5.Table 5.2.1.1: Monthly and Annual Normals (mm) at Savannah (1951-80)

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC YEAR211 210 260 213 159 102 107 76 58 50 88 162 1696Similar data exist for:* Bel-Air (St-Felix), rain gauge coded 293 339* Benares, rain gauge coded 296 349* Riviere-des-Anguilles, rain gauge coded 301 330

The Probable Maximum Daily Precipitation16 for various return periods is as follows:Return Period Savannah SE

(years) (mm/d)50 435

100 488200 540500 607

1 000 663

5.2.2 TemperatureThe air temperatures measured at the Plaisance Meteorological Services" provides data closest toSite, these are given in Table 5.2.2.1.

Table 5.2.2.1: Absolute maximum, minimum and average temperatures at PlaisanceNIONTH JAN FEB MLAR APR NLA'V JUN JIL AULG SEP OCT NOV' DECMean(°C) 25.9 25.9 25.6 24.5 22.9 21.3 20.7 20.3 21.0 22.1 23.6 25.1Abs. Maxi (0 C) 29.4 29.3 28.9 27.9 26.3 24.7 23.9 23.7 24.5 25.7 27.5 28.8Abs. Mini (°C) 22.5 22.6 22.3 21.1 19.5 18.0 17.5 16.9 17.5 18.4 19.7 21.3

Other data such the Wet Bulb Thermometry, of pertinence to the design of the Power Station, areavailable from the same source.

15 B. M. PADYA: Climate ofMauritius.

l6 Data communicated by Proponent

7 B. M. PADYA: Climate of Mauritius

5.2.3 Wind data

5.2.3.1 Wind data under normal climatic conditions5.2.3.1.1 Trade WindsThe trade winds range typically between 4 to 16 knots, with occasional peaks at 21 knots reached at1 2hOO, particularly during the winter season. The wind speeds fall considerably between l 8h00 and22hOO and remain low during the night, to reinforce again at about 8hOO.At night, at about 02hOO to 03hOO, land breezes start to blow to reach a maximum at dawn, therebycontributing to an increase of the intensity of the trade winds.

5.2.3.1.2 Average wind distributionWind data are continuously recorded at Plaisance, which is closest to Site. The monthly winddistribution for Plaisance has been illustrated by the wind roses in Appendix H drawn from Climateof Mauritius'8 .

5.2.3.2 Cyclonic WindsThe southwestern Indian Ocean is a region known for its cyclonic activity. Cyclones are very low-pressure regions, which have very high wind speeds that increase in magnitude in the direction ofthe eye of the cyclone. Tropical cyclones usually occur during the months of December to May.February is the most active month in terms of cyclonic formation; this is based on the data collectedby the National Meteorological Services at Vacoas. Table 5.2.3.2.1 indicates the monthlyoccurrences of observed cyclones.

Table 5.2.3.2.1: Monthly Percentage Occurrences of observed Cyclones (1960-1983)MIONTH DEC JAN FEB MIAR APR MIAY TOTAL% 18.1 20.8 30.6 18.1 9.7 2.8 100

From the observation of cyclonic wind speeds during the same period, the National MeteorologicalService has also established that the average for the wind velocities is 140 kmi/h (75 knots). Thedirection of cyclonic gusts depends on the path of the cyclone but will be in an easterly to northwestdirection. The Return Period for hourly winds and peak gusts has also been worked out from thecyclone data available and is indicated in Table 5.2.3.2.2 below.Table 5.2.3.2.2: Statistical distribution of cyclone wind velocity observed at Pamplemousses(1960-1983)

Return Period (ears) 100 50 15 5Hourly Wind (km/h) 125 112 90 72Peak Gusts (km/h) 230 200 160 130

18 B. M. PADYA: Climate of Mauritius.

5.2.3.3 Site Exposure to WindsThe relevance of the wind data detailed above is obvious from the point of view of:designing of buildings and constructions* atmospheric dispersion of pollutants from the plant and the sugar factory stacksThe Site will be under the influence of trade winds. Furthermore, cyclonic conditions may inducevery strong winds reaching the Site from the ocean.

5.3 GeologyThe Site is situated over weathered and pyroclastic basalt flows of the Intermediate Volcanic Series.This third activity phase occurred during the Pliocene, i.e., between -3.5 to -1.7 million years represent. See Figure 5.3.1.

The pyroclastic formations (fine volcanic tuffs) form a discontinuous cover more or less thick in theSouthern part of the caldera (Chamarel, N of Grand Bassin). Some pyroclastites formed at the rimof some craters, through their accumulation therein (crater W of Grand-Bassin).Irregular piling of basaltic flows present cumulated thicknesses that can exceed 1 00m.. Healthyflows alternate with flows transformed by weathering processes, a sign that emissions of lavas, farfrom being continuous, have occurred intermittently.

No detailed information specific to Site is available.

5.4 PedologyThe general pedology of the region has been mapped according to both the "Hawaiian"classification1 and to the ORSTOM classification 20 ; the Project Site has been overlaid to bothpedological maps of the region as shown in Figure 5.4.1 and Figure 5.4.2.The soil type that can be identified within the project area is the Low Humic Latosol soil, in itsstony phase, L2 of the Reduit Family.

This corresponds to 12 soils in the ORSTOM Classification, described therein as follows: "solsbruns a structure polyhedrique moyennement developpee, blocs de basalte doleritiques poreux avaccortex d'alteration frequente, debris de roches plus ou moins alteres en nombre variable au-dela de500mm."

5.5 Surface Hydrology and Hydro-geology5.5.1 Regional Surface HydrologySavannah Sugar Estate lies within the catchment areas of River du Poste, River St-Amand andRiver Tabac, as described in the foregoing, and in particular in Figure 5.5.1.1. The estate derives thetotality of its irrigation and factory water requirements from water rights on the said rivers.'9 PARRISH & FEILLAFFE: Soil Map of Mauritius. M.S.I.R.I. 1962.

2 0 p WILLAIME: Carte Pedologique de Ille Maurice. ORSTOM & M.S.I.R.I. 1984.

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F 7 Caillouteux -blocs en nombre moyen DE SAVANNAH Ltd.Construction & Operation of a

Sols caillouteux (taux de pierrosit6 >60%/) sur 50cm en moyenne 83 MW Coal/agasse-Fired Power Plant

pierres et blocs en profondeir at Savannah

Sols pierreux et caillouteux (taux de pierrosit6 >80%) sur 40cm Figure 5.4.1 - Pedological Maps

au maximum, blocs et/ou dalles en profondeur Scale 1:5 000

Date June 2005m Sols caillouteux (taux de pierrosit6 >60%) sur 50cm en moyenne, pierres Job No. 2436

et blocs en profondeur - 616ments grossiers superficiellement alt6r6s S.I.G.M.A. - Ove Arup & Partners

Associated Consufting Engineers19 Church Street - Port Louis -Mauritus

Tel. 212 3734/5 212 0962 212 2145 Fax (230)208 0375

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Soil oupsCOMPAGNIE THERMIQUESoil roupsDE SAVANNAH Ltd.I Latosolic Red Prairie Soils Construction & Operation of aSpecial Phases 83 MW Coal/Bagasse-Fired Power Plant

F/1/-/ Shallow andGr-/v at SavannahShalowanGravllyFigure 5.4.2 - Soil Map

________Scale 1:5 000Very Rocky Date June 2005

Job No. 2436

S.I.G.M.A. - Ove Amup & PartnersAssociated Consulting Engineers

19 Church Street - Port Louis - MauritusTel. 212 3734/5 212 0962 212 2145 Fax (230)208 0375

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N PSG AConstruction & Operation of a83 MW Coal/Bagasse-Fired Power Plant

at SavannahFigure 5.5. 1.1 - Catchment Ame

scale 1:150 000Date May 2005

Job No. 2436

S.I.G.M.A. - Ove Arup & PartnersAssociated Consulting Engineers

I9Chwvch slree- Pod Louis- MaIJIitjTel. 212 3734/5 212 0082 212 2145 Fax (230)208 0375

MT-MD, Savannah's partner in the CTSav venture, lies within the catchment area of River LaChaux, from which it receives water for its factory and for irrigation.

5.5.2 Site HydrologyThe Savannah Site is located on the left of the River Tabac catchment, as can be seen in Figure5.5.1.1. The Site itself displays no conspicuous drainage network, but at Savinia, to the SE of Site, asmall watercourse springs and runs to the sea close to Le Souffleur.

5.5.3 Hydro-geology

5.5.3.1 Regional Hydro-geologyThe entire region lies on top of the Nouvelle France - Rose Belle - Plaisance Aquifer. For a detailedaccount, reference is made to the "Carte Geologique et Schema Hydrogeologique" drawn in July1999 and reproduced in Figure 5.5.3.1.1

The coastal reservoir near Plaisance is very productive near Mare-Tabac. And MT-MD forirrigation purposes and the CWA, for domestic water production, exploit the aquifer as described in§ 4.6 of the foregoing.

5.5.3.2 Site Hydro-geology

No aquifer exploitation is carried out in the vicinity of the CTSav Site.

5.6 Air Quality

In as much as atmospheric pollution is concerned, the following pollutants could be generated as aresult of current activities around the Site.

5.6.1 PM, C02, NOx, SOx, CO, POP's Emissions

Emissions of NOx, SOx, CO, CO2, PM and POP's can be attributed to the following sources

identified by the Ministry of Environment and Quality of Life as major air pollution sources {RioBio-diversity Treaty (1991)}:* Vehicle traffic* The Union St-Aubin Sugar Factory* The Savannah Sugar Factory* The Mt-MD Sugar Factory* The CTDS coal-fired power station at Union

5.6.2 Baseline DataThe regional air quality is presently modified from initial conditions successively by:* the operation of Union St-Aubin, Savannah (La Baraque) and MT-MD sugar factories each year

from mid-July to end November, due to the combustion of bagasse during that period* the burning of sugar-cane fields during the crop season

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Date June 2005V AQUIFERE DES PLAINES DU NORD

At the end of 2006, MT-MD and Savannah sugar factories will cease operation, and therefore theiremissions to atmosphere, to be replaced in 2007 by CTSav

It can be assumed that the baseline for the assessment of the impacts of the power station is thesituation prevailing with the aforesaid sugar factories in operation during the crop season, andCTDS during 11 months. So that the baseline will be that prevailing with:* bagasse combustion and coal combustion during the crop season plus burning of cane fields* coal combustion off crop season

With reference to emissions from bagasse furnaces (see Appendix I hereto) and the CTDS EIAreport, typical emission rates will then be as per Table 5.6.2.1 below.

Table 5.6.2.1: Typical Atmospheric Emissions affecting the Base Line Air Quality

Pollutants Emission Rates Hourly Emission Rates (Mass/h) CTDS (coal)USAB La Baraque MT-MD Concentration Mass/h

PM 60.42kg/h 53.25kg/h 30.41 kg/h 150mg/Nm 3 18.17kg/hSo2 3.23 kg/h 2.46 kg/h 0.51 kg/h 1.6 gm/Nm3 280 kg/hNOx 600 mg NOx/ kgB 38.95 kg/h 2.85 kg/h 5.58 kg/h 650 mg/Nm3 92.04 kg/hCO 1 165 mg CO/kgB 56.63 kg/h 79.77 kg/h 28.99 kg/h 200 mg/Nm3 37.5 k/gCO2 780 gm CO/kgB 32.4 ton/h 32.24 ton/h 25.7 ton/h 268 gm/Nm3 36 426 kg/hVOC 200 mg VOC/kgB 8.3 kg/h 8.3 kg/h 6.6 kg/h 2.9 mg/Nm 3 0.388 kg/hPb 8x10-3 mg Pb/kgB 0.332 gm/h 0.32 gm/h 0.263 gm/h 2.43 pg/Nm 3 3.30 gm/hF - 8.7 mg/Nm3 1 163 gm/hHCL 1.86 mg HCI/kgB 83.7 gm/h 83.7 gm/h 66.4 gm/h 69 mg/Nm3 9 300 gm/hPOP 0.10 ng/Nm3 0.012 mg/h 0.012 mg/h 0.001 mg/h 0.014 ng/Nm3 0.002 mg/h

TCH - 140 - 140 - 106Combustible Bagasse bagasse bagasse coalBuming rate 41.5 ton/h 41.33 ton/h 32.9 ton/h 15.5 ton/hNm3/h 190000 189486 101 364 141 600

Each of these emission sources must be taken separately

5.6.3 Dust EmissionsDust is known to be emitted when the fields are ploughed and re-conditioned prior to being re-planted. But these dust emissions have never been estimated.

5.6.4 Ambient Air QualityBased upon the knowledge of the emission rates, stack height, stack gas exit velocities, the EPA-approved numerical model ISCST3 has been run, using climatic data prescribed, to compute themaximum concentrations of the above-listed pollutants at various locations in the Projectenvironment.

The proposed Air Quality Standards for Mauritius may be compared with the maximumconcentrations that have been computed in respect to the Sugar Factory stack emissions - details of

Computer Modeling Results in Appendix B - under various Observation Time scenarios, and whichare given in Table 5.6.4.1.

Table 5.6.4.1: Ambient Standards (maximum) compared withMaximum Computed Concentrations near -Site

Ambient Standards Computed ConcentrationsPollutant Maximum (Vg/m 3) Maximum (ig/m 3 )lh 8h 24h Annual lb 3h 24h Annual

CO 25 000 10 000 200 180.3SO2 350 200 50 120.8 21.09 0.3NOX 200 9.6PM1O 100 50 25.2PCDD 32x1e-9 7.4x I e-9 1.Ixle-9

The gaseous pollutants seem to occur at maximum concentrations that are, whenever comparable,of the same order of magnitude as the maximum ambient Standards proclaimed by Mauritius.

5.7 NoiseA noise survey of the Site is available. It has been carried out on the 12th May 2005 between 11 h 10and I lh45 and the dBA and dBC levels recorded at various locations around the future site areshown in Figure 5.7.1.

The region must qualify as a calm rural environment given its location and in the inter-crop season,except in the close neighbourhood of the Sugar Factory during the crop season.

SPL measured on the 12 May 2005 around 11h30

SPL Observation Points (referred to Figure 5.7.1)#1 #2 #3 #4 #5

dbA 56.5/57.4 53.1/54.6 53.5/55.1 58.8/57.8 54.8/53.6dbC 63.5/65.3 63.1/69.0 63.2/59.4 71.0/75.7 76.2/77.5

With passing VehicledbA 79.9 80.4 71.3dbC 82.7 90.0 85.6

SPL measured on the 19 June 2005 at 21h30

SPL Observation Points (referred to Figure 5.7.1)#1 #2 #3 #4 #5

dbA 41.2/42.5 50.8/45.7 59.3/60.7 46.8/40.8 56.6/50.1dbC 63.5/65.3 57.0/56.2 72.0/74.9 60.4/52.0 72.0/71.8

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Construction & Operation of;83 MW Coal/Bagasse-Fired Power Plan

at Savanna,Figure 5.7.1 -Noise Survey Locatio:Savar.ria

;Scale 1:25 00Date June 200

Job No. 243

S.l.G.M.A. - Ove Arup & PartnernAssociated Consulting Engineern

19 Church Street- Port Louis - MauridtuBL,UL ~Tel. 212 3734/5 212 0962 212 2145 Fax (230)208 0371

5.8 Floral Environment

5.8.1 Nature ReservesOnly sugar cane is encountered in the Site environment, the primitive or native vegetation ofMauritius having long ago been destroyed in favour of sugar cane and by the introduction of exoticspecies dominating non-cultivated zones like:* Casuarina equisetifolia (filaos)* Psidium littorale (strawberry guava or 'goyave de chine' in Vernacular)• Ravenala madagascariensis (traveller's palm), ...

Native forest remnants are still in existence in Mauritius, as can be inferred from Figure 5.8.1extracted from the 1994 NPDP which shows the Nature Reserves farsightedly designated as farback as 193721 as a result of a survey of native vegetation remnants. With reference to the map ofFigure 5.8.1, the Combo Reserve (208.8ha) is closest to the Power Station site.

Then further due NW of Combo:* Le Cabinet Reserve (17.73 ha)* Les Mares Reserve (5.10 ha)* GOULY pere Reserve (10 95 ha)* Bois Sec Reserve (5.91 ha)

But the richest and largest reserves are the Macchabee/Bel Ombre reserves (3 611 ha), which havebeen combined with adjacent lands to constitute the Black River Gorge National Park22 . The Parkincludes Bassin-Blanc (454 ha) considered to be the part of the Park most critical to biodiversity.The 500ha space between Piton Savane, Mt Cocotte and Bassin-Blanc, about 7k due NW of Site hasthe Island's highest diversity of endemic plants.

5.8.2 Endangered SpeciesNone exist in the proximal vicinity of Site. But they exist in the aforesaid Nature Reserves whichoffer refuge to dozens of critically rare species, virtually all of them endemic and restricted to theaforesaid native vegetation remnnants particularly in the Macchabee and Bassin-Blanc zones. In spiteof the fact that the native systems in these reserves have already been altered beyond recovery,these protected sites still offer prospects for maintenance of many species that would be extinctwithout this habitat.

The Black River Gorges National Park hosts most of the 50 rarest species in Mauritius23 .Four Mauritian species are listed in the Plant Red Data Book24 ), namely:

2' R. E. VAUGHN & Paul Octave WIEHE: 1937. Studies on the vegetation of Mauritius. Part 1: A preliminary Surveyof the Plant Communities. Journal of Ecology, Volume 25 No 2 p2 8 9-3 4 3 .22 Department of Environment 1991. The Black River Gorges National Park. Ministry of Environment and Land Use,Mauritius.23 Department of Environment 1991. Top 50 Rarest Native Plants in Mauritius.24 G. LUCAS & H. SYNGE in The IUCN Plant Red Data Book. Threatened Plants Committee, Survival ServiceCommission, International Union for the Conservation of Nature and Natural Resources. Morges, Switzerland. Also:IUCN Conservation Monitoring Center. 1987; IUCN Directory of Afrotropical Protected Areas; IUCN Commission onNational Parks and Protected Areas. Gland, Switzerland.

t"TVAf I xIfttLYkIjtJfl l Jt &t v t ir t Itt.

Construction & Operation of a 83 MW Coal/Bagasse-Fired Power Plantat Savannah

LEGEND A

A PROPOSED & POTENTIAL MARINE PARK - B-B BARABs

A BBMANGROVES

B' WETLANDS At L A BFR FISHERIES RESERVES

B-BSAtND DUNES

BCOASTAL CONSERVATION AREAS

I MOUNTAINS AND MOUNTAIN RESERVFS B

NATURF RESERVES A .

- LAND PRONE TO EROSION

FORESTS

- ' NATIONAL PARK

NATURE RESERVES ;/BI. L. Pm

i'2. CopsdeGede d C .3. Peeerfi~ '

6. Go ly Pert .

8. Maccbabee/ ld Ombr ( a S ----

9 Co.bB,

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BA

FR -FR

13 SAVANNAHPOWER PLANT '<A

- - Figure 5.8.1 - Forest and Natural ReservesScale 1:300 000Date June 2005

Job No. 2436S.I.G.M.A. - Ove Arup & Partners

Associated Consulting Engineers19 Church Street - Port Louis -Mauritius

Tel. 212 3734/5 212 0962 212 2145 Fax (230)208 0375

Crinum mauritianumDiospyros sp. nov. (presumably D. hemiteres)Tetrataxis salicifoliaDrypetes caustica

The last three of the above are known to occur in the SE of Mauritius

Of the 80 species of orchids present in Mauritius, 25% are endemic and many of them exist atBassin Blanc.

5.9 Faunal Environment

5.9.1 Endemic WildlifeThere is no endangered native wildlife in the proximal neighbourhood of the Project which hosts nonative forest remnants. Mauritius, however, initially counted 25 species of indigenous birds. And ofthese:* only I can still be found outside native forest remnants* 16 are now extinct25

The aforesaid 500ha space between Piton Savane, Mt Cocotte and Bassin-Blanc, is also regarded asthe most important habitat of endemic birds.

5.9.2 Exotic SpeciesExotic species such as monkeys, wild pigs, deer and birds have to-day, overwhelmed the primitivenatural fauna.

At "La Vanille" Crocodile and Tortoise Park, created in 1984, already mentioned in the foregoingunder touristic activities, besides being a zoo of Mascarene fauna, also beeds exotic speciesincluding Crocodiles (Crocodilus niloticus) imported from Madagascar, and the giant Aldabratortoises. In fact, Vanilla Park claims to be the World's largest breeder of these giant tortoises.

Crocodiles are bred for their skin used in leatherwear (maroquinirie).

25 R. E. VAUGHN, 1968. Mauritius and Rodrigues. In Conservation of Vegetation in Africa South of the Sahara, 1. &0. HEDBERG pp 265-272. Proceedings of a Symposium held at the 6h' Plenary Meeting of the 'Association pourl'Etude de la Flore d'Afrique Tropicale', Uppsala, September 12-16, 1966. Acta Phytogeographica Sueicica 54, Uppsala.



Chapter 6: Environment Management Plan

6.1 IntroductionIn this Chapter, negative as well as positive impacts associated with the production of electricity atthe coal-fired steam power plant in the specific environment of La Baraque are identified duringConstruction Phase as well as during Operational Phase. These impacts will be assessed andappropriate measures to mitigate the negative impacts will be proposed for implementation.

6.2 Negative Impacts at Construction

6.2.1 Biological Pollution of SiteA number of site operators and workers will be mobilized on site for Site preparation, theconstruction of the power station and ancillary works and the daily production of wastewater andsolid wastes must be expected during the Construction Phase.

6.2.1.1 Source of ImpactDomestic sewerage will contain polluting components whose typical concentrations are given inTable 6.2. 1.1.1.

Table 6.2.1.1.1: Quality of typical domestic effluents from Site Amenities

TYPICALVALUESPARAMETERS Units EffluentsCOD mg/e 250-450Total KJELDAHL N (TKN) mg/M 25-45NH 4 - N mg/e 10-25P°4 - P mg/e 3-7Total Suspended Solids (TSS) mg/e 127-187pH 6.6-7.7NO3 - N mg/C NilColiforns No 106 - 108

These effluents cannot be discharged as such on Site as they would eventually be carried by stormrun-offs to the rivers waters, thus contaminating them particularly in terms of P concentrations andColiforms. Mitigation is therefore necessary.

6.2.1.2 Mitigating MeasuresNo connection of Site amenities to sewer collector is possible. During the Construction Phase,septic tanks will be constructed on Site, for biological treatment of the influents during a retentiontime of at least 24 hours. The septic tanks will be designed according to* the characteristics of the waste waters* the daily flow of the waste waters* the environmental conditions and constraints pertaining to the specific site.

The Disposal of the effluents from the septic tank by absorption pits still represents potentialsources of diffused pollution to the water table and is not recommended by the Waste WaterAuthority. This is why the Proponent is proposing individual septic tanks cum leaching fieldsdesigned and dimensioned to suit the septic tank effluent flow, which will also provide additional"polishing" to the effluents from the septic tanks. Thus the effluents ultimately released from theleaching field will have the quality described in Table 6.2.1.2.1 below.

Table 6.2.1.2.1: Typical Domestic Effluent Composition at Various Stages of Disposal 26

POLLUTION PARAMETERS Influents to Effluents from 1.0 m belowSeptic Tank Septic Tank Leaching Field

COD 250 - 450 mg/e 90 - 120 mg/t <20 mg/eTotal KJELDAHL Nitrogen (TKN) 25 - 45 mg/e 20 - 40 mg/e < 5 mgleNH3 Nitrogen 10 - 25 mg/i 20 - 40 mg/e TraceTotal Phosphate 3 - 7 mg/C 3 - 7 mg/C Trace to I mg/tTotal Suspended Solids (TSS) 127 - 187 mgle 40 -60 mg/e TracepH 6.6 - 7.7 6.0 - 7.2 6.0 - 7.2Colifonn 106- 108 104 - 106 0o-io

6.2.2 Accumulation of Solid WastesSolid wastes, will be produced on Site during the Construction Phase:* Bio-degradable like food wastes left by Site staff, wood cuttings. Non-bio-degradable like paper, cardboard, plastic, iron cuttings, concrete spills, normallyaccumulating around any construction Site.

6.2.2.1 The ImpactFood wastes, in particular will attract pests and vermin, like rats, stray-animals, etc. Accumulationof other wastes within the Site would create a visual impact that is not appropriate anywhere and afortiori, within the sugar factory area.

6.2.2.2 Mitigating measuresSolid wastes generated on Site during the Construction phase, will be collected in bins and hauledaway to safe disposal at the nearest Transfer Station, in appropriate Lorries every day by DistrictCouncil solid waste operators.

26 Source: adapted from Ministere de L'Environnement, Cahiers Techniques de la Direction de la Prevention desPollutions No 5, 1981

6.3 Negative Impacts during Operation Phase6.3.1 Atmospheric Pollution by Particulate and Gaseous EmissionsThe particulate and gaseous emissions will not be the same in the crop season scenario, whenCTSav Power Station as well as USAB sugar factory will run on bagasse, and the inter-crop seasonscenario, when CTSav and CTDS will operate on coal.

6.3.1.1 Origin of the Atmospheric PollutionPursuant to the above definition of the Crop Season Scenario emissions, typical stack gasesemissions from the various sources will be as per Table 6.3.1.1.1 below

Table 6.3.1.1.1: Typical exhaust gas emissions in the Crop Seasonfor both CTSav boilers on

Pollutants Concentration in biomass Emission Rates CTDS (coal)Flue Gas (Mass/Nm 3 ) (Mass/h)USAB CTSav USAB CTSav Concentration Mass/hPM 318mg/Nm3 150mg/Nm3 38.7kg/h 45.64 150mg/Nm 3 18.17kg/h

91.28kg/hS02 66 mg/Nm 3 66 mg/Nm3 8.0 kg/h 20.08 40 1.6 gm/Nm 3 280 kg/h16kg/hNOx 306mg/Nm 3 306 mg/Nm 3 37.3 kg/h 93.1186.2 650 mg/Nm 3 92.04 kg/h

kg/hCO 4 8 gm/Nm3 4 8 mg/Nm3 579.7 kg/h 1.46 200 mg/Nm 3 37.5 k/g2.92ton/hCO2 298 gm/Nm 3 298 mg/Nm3 36.3 ton/h 81.28 268 gm/Nm3 36 426 kg/h

162.56ton/hVOC 476 mg/Nm 3 476 mg/Nm3 58.0 kg/h 144.83289.6 0.388 kg/h6 kg/hPb 0.003 mg/Nm3 0.003 mg/Nm3 0.33 gm/h 0.91 0.023 gm/Nm3 3.30 gm/h

1.82gm/hF -- -

163 gm/hHCL 0.547 mg/Nm3 0.547 mg/Nm 3 66.6 gm/h 166.4332.8 65.7 gm/Nm3 9 100 gm/hgm/hPOP 0.10 ng/Nm 3 0.10 ng/Nm 3 0.012 mg/h 0.06 mg/h 0.0 14 ngNm3 0.002 mg/h

TCH - 140 - 2x350Combustible

bagasse bagasse coalBuming rate 41.5 ton/h 2x78.8 tonh 15.5 ton/hNm 3/h

121 807 2x304 270 141 600

Reference must be made to the primary measures:* adopted by the Sugar Factory and implying stack gas scrubbers* proposed by the Power Plant proponents, implying an ESP at CTSav, similar to that at CTDSPursuant to the above definition of the Inter-crop Season Scenario emissions, typical stack gasesemissions from the various sources will be as per Table 6.3.1.1.2 below.

The dispersion of the gaseous pollutants in the atmosphere will be simulated numerically using theEPA ISCSCT3 numerical code with atmospheric data as available in Mauritius. Attention is drawn

however to the implicit shortcomings of that procedure, particular in view of the availability ofappropriate atmospheric data input, which would also have to be addressed should the newlyproposed AERMODE code be adopted27 28

Table 6.3.1.1.2: Typical exhaust gas emissions in the inter-Crop Seasonassuming both CTSav boilers on

Pollutants Concentration in Emission RatesBiomass flue gas Coal flue gas CTDS CTSavPM 318mg/Nm 3 150mg/Nm 3 18.17kg/h 45.64kg/hS02 66 mg/Nm3 1.48 gm/Nm3 280 kg/h 450 kg/hNOx 306 mg/Nm3 650 mg/Nm 3 92.04 kg/h 197.8 kg/hCO 4 800 mg/Nm 3 200 mg/Nm3 37.5 k/g 60.85 kg/hCO2 298 mg/Nm3 268 gm/Nm3 36 426 kg/h 81 544 kg/hVOC 476 mg/Nm3 2 734 mg/Nm 3 0.388 kg/h 0.832 kg/hPb 0.003 mg/Nm3 0.023 mg/Nm3 3.30 gm/h 7.0 gm/hF - 0.008 mg/Nm3 1 163 gm/h 2.43 gm/hHCL 0.547 mg/Nm3 65.68 mg/Nm3 9 300 gm/h 19.98 gm/hPOP 0.10 ng/Nm 3 0.0 14 ng/Nm3 0.002 mg/h 0.0043 mg/h

Combustible coal coalBurning rate

15.5ton/h 37.5ton/hNm3/h 141 600 304270

6.3.1.2 Impacts of CO 2 Emissions

6.3.1.2.1 Contribution to Global WarmingThe "Greenhouse Effect", which is the term used to describe Global Warming is usually related tothe releases of C02, CH4 , N2 0, etc29. In an attempt to provide a simple measure of the relativeradiative effects of the emissions of the various greenhouse gases, the Intergovernmental Panel onClimate Change (IPCC) has introduced the concept of Global Warming Potential (GWP). TheGWP of a gas reflects the cumulative radiative forcing of that gas over a specified period of time (or"time-horizon"), beginning with the moment it is emitted. The GWP for a given gas is expressed interms of that gas' radiative forcing relative to the forcing associated with the same mass of CO2 overthe same time-horizon, and for that purpose, CO2 has a GWP of 1. But CO also participates to theGreenhouse Effect and its participation is measured in terms of CO2 equivalent. Thus, 1 gm of CO isequivalent to 7gm of CO2.

27 Good Practice Guide for Atmospheric Dispersion Modelling. National Institute of Water and Atmospheric Research.Ministry of Environment. NEW ZEALAND.

28 Comparison of Regulatory Design Concentrations. EPA June 2003.29 Global Change - Electronic Edition - Global Warming Potentials. 100-year time-horizon, 1992, 1995.http://www.globalchange.org/aciall//96jul

1 d.htm

Table 6.3.1.2.1.1: Global Warming Potentials for various Greenhouse Gases

GASES GLOBAL WARMING POTENTIAL1992 1994 1995

CO2 I I 1CH4 I1 24.5 21N20 270 320 310

6.3.1.2.2 Intensity of Impact due to CO2 emissionsAs mentioned in the foregoing, a considerable amount of CO2 is absorbed by sugar cane fieldsduring their growth cycle. This amount has been estimated at some 864 642 tons p.a. based on thefollowing data from the MSIRI Yearbook for 2003:* Surface cropped by USAB Riche-en-Eau, MTMD, Savannah: 3 000ha* Tonnage of cane processed by USAB, Riche-en-Eau, MTMD, Savannah: 1 521 772 tons* Crop duration in 2003: 135/lSOdays, i.e., July to early December* Carbon content of Cane: 15.5%

Thus, the uptake by growing canes (-864 642 tons p.a.) will offset totally the CO2 emissions (+423360 tons p.a.). And globally, within a closed 'system' involving the sugar factory activity, there willbe no contribution to the Green House Effect from bagasse-fired power plants.

When the CTDS Power Plant comes into operation, (8 000 hours p.a. and about 15 tons of coal perhour) emissions will be boosted up by + 282 000 tons CO2 p.a. This will be further increased bysome 359 000 tons p.a. from CTSav (4 400 hours p.a.) placing the net annual contribution to GreenHouse Effect of 200 000 tons of CO 2 per annum. This is a maximum, as both CTDS and CTSavmay not be called at 100% rating all the time.

6.3.1.2.3 Mitigating Measures

6.3.1.2.3.1 Accounting CO2 emissions in Global EffectFrom the foregoing, CO2 is absorbed by vegetal that will fix the C-content for their development.Inasmuch as the project area + its cane fields + the CTDS Plant forming a closed system areconcerned, emission rates will exceed the uptake rates, but neighbouring vegetated 'systems', canefields and forests will also participate in the uptake.

The power generation potential of the CTDS and CTSav power stations will have to be retained inthe planning of Electrical Power Generation in Mauritius for the years to come, so as to optimizethe overall contribution of Mauritius to the Greenhouse Effect and Global Warming.

6.3.1.3 Impacts of CO Emissions

6.3.1.3.1 Health Hazard due to CO emissionsInasmuch as human beings are concerned, inhalation of CO can cause poisoning. The symptomswould be:

* Body as a whole: headaches, irritability, confusion, fainting, impaired judgement,unconsciousness, bizarre behaviour

* Respiratory: shortness of breath, increased rate of breathing, chest pain, stop breathing* Eyes, ears nose & throat: bluish colour to lips* Skin: bluish colour to fingernails, pale skin* Gastrointestinal: nausea and vomiting* Heart and blood vessels: abnormal heart beat, rapid heart beat, low blood pressure* Nervous system: hyperactivity, convulsions, coma, shock

CO exposures, by reducing the blood's ability to carry Oxygen, especially affect unborn babies,infants and people with anemia or a history of heart or respiratory disease".

Breathing low levels of CO can cause fatigue and increase chest pain in people with chronic heartdisease. Breathing higher levels of CO causes the symptoms described above in healthy people. Atvery high levels, it causes loss of consciousness and death. Between 300 and 500 people die everyyear in the USA, from exposure to residential combustion appliances.

6.3.1.3.2 Health Hazard due to CO emissionsThe uptake of CO by humans is a function of exposure time and concentration of CO in the air.Blood COHb is expressed in terms Exposure Time (hr) and CO (ppm) concentration in Figure6.3.1.3.2.1. This has been studied by various researchers, who have produced mathematicalexpressions for the uptake of CO, namely the HALDANE equation and the more elaborateCOBURN-FORSTER-KANE equation.

6.3.1.3.2.1 Ambient ConcentrationsIn terms of ambient concentrations in the Atmosphere, reference must a priori be made to the localMauritius Standard32 , that sets out the level of ambient concentrations for a given averaging period.They are given in Table 6.3.1.3.2.1.1 below. In the said table, Baseline data, it is recalled impliesambient conditions resulting from the operation of:* Union St-Aubin (USAB), La Baraque & MT-MD sugar factories concurrently with CTDS (coal)in the crop season;* CTDS (coal) alone in the inter-crop season

Thus the simulations take the following gaseous emission sources into account during the crop andintercrop seasons:

* Baseline Crop season: Savannah SE, Union St Aubin SE, MDMT and CTDS* Baseline intercrop season: CTDS only

* CTSav Operational Intercop season: CTSav (using coal as combustible) and CTDS. CTSav Operational Crop season: Union St Aubin SE, CTSav (using bagasse only ascombustible) and CTDS

30 American Lung Association Fact Sheet: Carbon Monoxide.31 Wayne State University. School of Medicine. Carbon Monoxide HQ.32 Government of Mauritius. Governrment Notice No 105 of 1998. Regulations made by the Minister under Section 35of EPA 1991.

The ambient concentrations resulting from the operation of these plants have been computed usingthe ISCST3 EPA approved dispersion code.

Table 6.3.1.3.2.1.1: Modification of Ambient CO Concentrations by CTSav PSAveraging Period Maximum Ambient CO Concentrations (Vgm/M 3)Mauritius Baseline data With CTSAVStandard

Inter-crop SeasonIh 25 000 14.65 1 8.858h 10 000

Crop SeasonIh 25 000 180.34 1222.998h 10 000

The computed maximum CO concentrations for averaging times of Ih and 8h have also beenincluded in Table 6.3.1.3.2.1.1. They are considerably less than the Standard ambient concentrationfor Mauritius.

6.3.1.3.2.2 Emission StandardsProposed emission standards for Mauritius set the emission rate of CO at 1 000mg/Nm 3.The maximum CO production rate of 633mg/Nm3 will occur during the 5months period when theoperations of the Sugar Factory and of the CTDS Power Station will be concurrent, as can beinferred from Table 5.6.2. 1:* CO emission rate from the Sugar Factory: 4 800 mg/Nm3o CO emission rate from the CTDS or CTSav Plant: 200 mg/Nm 3

In that sense, due to a better combustion process with coal, CO emissions will decreasesubstantially. No mitigation is therefore necessary.

6.3.1.4 Impacts of Nitrogen Oxides emission6.3.1.4.1 Health HazardsNitrogen oxides exist as Nitrous Oxide (N20), Nitric Oxide (NO) and Nitrogen Dioxide (NO2).These oxides exist in the Atmosphere, produced naturally from bacterial and volcanic actions, in fargreater quantities than from man-made activities. The natural quantities are widely disperseduniversally resulting in low background concentrations. Health hazards related to direct exposure toNOx are summarised hereunder.* N2 0, commonly known as laughing gas, is a weak anaesthetic gas that has been in use since thelate 18th Century. When inhaled, it produces a variety of physiological effects includingdisorientation, fixated vision, throbbing or pulsating auditory and visual hallucinations, increasedpain threshold and deeper mental connections. These effects may last approximately a minute fora lungful on the gas, before dissipating.The primary dangers of N20 inhalation are: oxygen

3 Legal Supplement. Government Gazette of Mauritius No 92 29th August 1998.

30 X; lo

I 20

a oH0

co10-1/v --0200

1 2 3 4 5Exposure Time (hrs.)

Uptake of carbon monoxide by humans under resting conditions. COHb saturation after infinite exposure time (steady state conditions) is shown on each line.Redrawn from: Forbes, W.H., Sargent, F., and Roughton, F.J.W., 1945, "The rate of carbon monoxide uptake by normal men". Am. J. Physiol., 143, 594-608).

Figure 6.3.1.3.2.1 - Uptake of CO by HumaSource: Wayne State University. School of Medicine. Carbon Monoxide HQ Date June 20,

deprivation, frost bite, loss of motor control, Vitamin B12 interference, Folic acid interference,nausea.NO is a poisonous, odourless, colourless gas produced during high temperature combustion. Solong as its ambient concentration is < 0.5ppm, its biological toxicity is not significant34. But NOis a precursor to the formnation of NO2 and an active compound in the formation of 03. NO canalso interfere with the transport of 02 to body tissue and at higher concentrations, producessymptoms similar to those of CO. NO is highly irritating to the skin, eyes, and the mucousmembrane. At higher concentrations, it may cause irritation of the throat and a burning cough.* NO2 is a highly toxic, reddish-brown gas with a very pungent odour. It is a strong oxidisingagent that reacts in the air to form corrosive HNO 3 as well as toxic organic nitrates. It also playsa major role in the atmospheric reactions that produce ground-level 03. In ambient air, NO2 isprobably the most important for human health. NO2 is highly irritating to the skin, eyes, and themucous membrane. NO2 can, at relatively low levels, cause irritation of the respiratory tract aswell as cause changes in the sensory perception, and is only potentially related to lung disease.At higher concentrations, it may cause irritation of the lungs, bronchitis and pneumonia, andlower resistance to respiratory infections. Continued or frequent exposure to higher levels ofNO 2 can cause pulmonary edema 35.

NOX will also participate in various atmospheric chemical reactions, such as photochemicalreactions stimulated by solar UV, which may produce a variety of oxygenated compounds thataccount for the visibility reduction and eye irritation associated with smog.

6.3.1.4.2 Formation of Acid Rain (HNO 3)This is another environmental impacts arise from the participation of the NOx in atmosphericchemical reactions. Acid rain is formed as NO2 reacts in the air to form corrosive HNO3 as well astoxic organic nitrates.

Acid deposition will affect:* aquatic ecosystems, and terrestrial animals dependent upon such ecosystems, basically through adecrease in the pH of the systems* terrestrial plant life, both natural vegetation and crops, by:- altering the protective waxy surface of leaves, lowering disease resistance- inhibiting plant germination and reproduction

- accelerating soil weathering and removal of nutrients- making more soluble, toxic elements such as aluminum, which when present in the soil in highconcentrations, can prevent the uptake and use of nutrients by plants* human health, due to:- an acidification of food, drink water and breathing air- an increase in the level of toxic metals such as Al, Cu, Hg in untreated drinking water supplies

6.3.1.4.3 EutrophicationThis occurs when a body of water suffers an increase of nutrients (excess N via "acid rainfall") thatreduce the amount of 0 in the water, resulting in the impoverishment of benthic and ichthyologiclife of lagoons, or the aquatic life of neighbouring water courses and pondages.

34 Oaklahoma Department of Environmental Quality. Nitrogen Dioxide Fact Sheet.3 Oaklahoma Department of Environmental Quality. Nitrogen Dioxide Fact Sheet.

6.3.1.4.4 The Greenhouse EffectIn fact it is N2 0 that contributes to the Greenhouse Effect and its GWP (see Table 6.3.1.2.1.1) interms of CO2 equivalent, is 31 Ogm of CO2.

6.3.1.4.5 Hazards to VegetalsThey are associated with temporary photosynthesis inhibition and other phytotoxic effects (due toconcentrations of NO and NO 2) on oat, Alfalfa grass, oranges, tomatoes and pinto beans -reproduced hereunder in Table 6.3.1.4.5.1. Information on the response of native vegetation to NO2is not available; neither are its effects on sugar cane or common local food crops available

Table 6.3.1.4.5.1: NOx doses reported to affect crops36

Effect Species Ambient air E ReferencelvlConcentration xpseEfetRfrnc

I Oats, NO: 744 l 5 h Temporary inhibited Hill & Bennettalfalfa NO 2: 1 000 photosynthesis (1970)

NO: 310 Reduction in rate of Capron & Mansfield2 Tomato NO2 : 470 20 h photosynthesis (1976)

3 Pinto Bean N02: 620 10/19 days Reduced fresh and Taylor & Eaton3 it en O:60 101 asdry weights (1966)Reduced number and Thompson et al.4 Oranges NO 2: 120-470 290days weight of fruit (1970)

5 Corn N0 2 :1 880 14 days No effect on growth Okanoetal(1985)

6.3.1.4.6 Intensity of Impacts

6.3.1.4.6.1 Ambient Concentrations

In terms of ambient concentrations in the Atmosphere, reference must a priori be made to the localMauritius Standard 37 that sets out the level of ambient concentrations for a given averaging period.They are given in Table 6.3.1.4.6.1.1 below. In the said table, Baseline data, it is recalled impliesambient conditions resulting from the operation of:* Union St-Aubin (USAB), La Baraque & MT-MD sugar factories concurrently with CTDS (coal)in the crop season;* CTDS (coal) alone in the inter-crop season


36 GOLDER Associates Inc (1997)37 Government of Mauritius. Goverment Notice No 105 of 1998. Regulations made by the Minister under Section 35 ofEPA 1991.

Table 6.3.1.4.6.1.1: Modification of Ambient N02 Concentrations by CTSav PSAveraging Period Maximum Ambient N02 Concentrations (pgm/M3)Mauritius Baseline data With CTSAVStandard Baseline_data _With_CTSAV

Inter-crop SeasonIh

24h 200 5.77 13.26Crop Season

Ih

24h 200 9.61 22.00

The numerical modeling of concentrations, results of which are given in Table 6.3.1.4.6.1.1, showsthat the increases in ambient concentrations that would result from the phasing out of MTMD andSavannah and the operation of the proposed CTSav power station, are less than the pre-projectannual average ambient NOx concentrations.

6.3.1.4.6.2 Emission RatesThe impact of NOx generation may be assessed with reference to the emission rates of the powerunit and to the Emission Standards proposed for Mauritius and which are:* proposed allowable NOx emission rate: 1 000 mg/Nm 3

The individual emission rates are:* 650 mg/Nm3 for CTDS and CTSav* 306 mg/Nm3 sugar factories.

They are therefore compatible with the emission rates allowable per Mauritius Standards. It must benoted that the NOx emission rates of the coal-fired plants are higher than those of the SugarFactory.

6.3.1.4.7 Mitigating measuresThe NOx emission rates would satisfy the Mauritius Guidelines for emission rates as well as theStandards for ambient NOx concentration which is 200[tg/m3 24h-average.

These low ambient concentrations are the result of atmospheric dispersion computations thatinvolve a certain number of approximations in particular of atmospheric parameters like the mixingheight, etc. Obviously at present only estimations of the concentrations can be made. A trueassessment can only be obtained by means of High Volume Air Sampling located within theradiation field of the CTSav stacks when the latter is in operation.

Precise measurement of the future radiation fields may eventually impose the installation of a liquidNH3 catalytic reactor to abate NOx emissions, although the probability for such appears quiteremote. It may therefore be wise at least to make technical provisions for the implementation of acatalytic reactor.

6.3.1.5 Impacts of Sulphur Oxides EmissionsCoal with a <1.0% S-content will be used in the Power Plant and S can be expected to appear in theflue gases as SO2 (295%) and SO3 (1-5%).

Uncontrolled SO, emissions are almost entirely dependent on the S-content of the fuel, as can beinferred from Table 3.2.6.2.1. A natural desulphurization of approx. 10% of the sulphur content ofthe coal occurs iri the furnace, as combination with the calcium content of the ash.SOX may be important pollutants for reasons explained below.

6.3.1.5.1 Health HazardsHealth effects have been observed, especially in combination with respirable PM (particulatematter).

6.3.1.5.2 Formation of Acid RainThe consequences of acidification of atmosphere have been laid out in detail in the foregoing. SO,,will contribute to the formation of acid rain by chemical reaction with the atmosphere.

6.3.1.5.3 Phytotoxic Effects on Native Vegetation and AgricultureNo information is available on the effects of pollutants on tropical species such as found inMauritius, or sugar cane. Consequently, to make up for that shortage on information the effects ofSO2 on:* various desert species, sub-tropical trees and two specimens of lichens can be used, as suggestedby GOLDER Associates, as a basis to asses the risks to native vegetationa corn and sorghum (C4 grasses similar to sugar cane) can be used to assess the impact ofemissions on sugar cane

6.3.1.5.4 Intensity of Impact

6.3.1.5.4.1 Ambient ConcentrationsIn terms of ambient concentrations in the Atmosphere, reference is made to the local MauritiusStandard38 that sets out the level of ambient concentrations for a given averaging period.They are given in Table 6.3.1.5.4.1.1 below. In the said table, Baseline data, it is recalled impliesambient conditions resulting from the operation of:* Union St-Aubin (USAB), La Baraque & MT-MD sugar factories concurrently with CTDS (coal)in the crop season;* CTDS (coal) alone in the inter-crop season


3 Government of Mauritius. Goverment Notice No 105 of 1998. Regulations made by the Minister under Section 35 ofEPA 1991.

Table 6.3.1.5.4.1.1: Modification of Ambient S02 Concentrations by CTSav PSAveraging Period Maximum Ambient S02 Concentrations (Vgm/m 3 )Mauritius Baseline data With CTSAVStandard

Inter-crop SeasonIh 350 117.04 242.324h 200 20.52 52.51Annual 50 0.17 6.21Crop SeasonIh 350 120.77 128.7324h 200 21.09 22.59Annual 50 0.26 0.62

Existing World Bank Guidelines are:. For unpolluted areas, ambient SO2 concentrations are <50[tg/Nm3 annual average, and<200,ug/Nm3 24-h average. For moderately polluted areas, the ambient SO2 concentrations are >50,ug/Nm 3 annual average,and >200[tg/Nm3 24-h average.

With reference to the above, the Project zone would be considered as an unpolluted area withambient SOx concentrations of 0.26,tg/Nm3 annual average, and 21.09%ig/Nm 3 24-h average.Values computed are lower than mandatory concentrations for averaging times greater than 1h, i.e.,for 24h and annual sampling times.

6.3.1.5.4.2 Emission RatesThe impact of SOx generation may be assessed with reference to the emission rates of the powerunit and to the Emission Standards proposed for Mauritius and set out by World Bank.In Mauritius:* the proposed standard for SO3 emission rate (for any source other than combustion processes andsulphuric acid plant): 120mg/Nm 3 supposed continuous* the proposed standard for S02 emission rate: 5 OOOmg/Nm 3, for lh maximum

Existing World Bank Guidelines are:a the lowest of 2 000mg/Nm3, or 0.200ton/day/MWE , or 500 t/day

6.3.1.5.4 Mitigating MeasuresIn Mauritius, the 120mg/Nm3 proposed concern SO3, which represents not more than 5% of themixture (SO2+SO3 ) emitted from coal combustion. If SO2 is concerned, the tolerable emission ratewould be pro rata of the SO3, 2 400mg/Nm 3.

During the intercrop season when the CTDS and the CTSav plants will be operational concurrently,the ambient concentrations of S02 for 1 -hour averaging time is 242.43pggm/Nm3 and this still will

be less than the mandatory ambient concentrations of 350[tgm/Nm3, although both plants willcertainly be called upon relatively frequently to operate at MCR.However, it is necessary to remember that:* the Gaussian Plume ISCST3 EPA model is based upon a certain number of assumptionsconcerning the mixing height, which is not measured in Mauritius, and makes use of wind datafrom Plaisance Airport* stack emissions proposed by the Proponent assume that the coal imported from RSA will be of0.6%S-content whereas from Table 3.5.6.4.2, the S-content of the imported coal, from theanalysis of Table 3.5.1. 1, lies in the 0.7%-09% range.• It may also be argued that the ISCST3 model could overestimate I-h concentrations,.

Thus from the above although the model indicates that the ambient air quality for various parameterswill be within permissible limits but with the uncertainties in both the model parametric requirementsand the vqriation of the characteristics of the coal imports, it is recommended that constant andsystematic monitoring of operational parameters and of ambient concentrations must therefore formpart of the Environmental Monitoring Plan:

(i) Controlling the CTSav flue gas ejection velocityThe flue gas ejection velocity when burning coal must not be allowed to drop below 20m/s.Numerical modelling has shown that the atmospheric dispersion is quite sensitive to ejectionvelocity. The Proponent is therefore invited to make proposals accordingly.

(ii) Monitoring of ambient SO2 concentrationsConsidering the variable sulphur content of the coal received from RSA, and the fact that the plantwill often be called at MCR, provisions should be made for the analysis of ambient S02concentrations using a HVAS within a radius of I 500m around the Power Station, taking intoaccount wind direction and under MCR operation conditions.

6.3.1.6 Impact of Particulate Matter emissionsPotential impacts associated with Inhalable Particulate (PMIO) are described hereunder.

6.3.1.6.1 Health hazardsMajor concerns for human health from exposure to inhalable particulate matter can have thefollowing effects":* Effects on breathing and respiratory systems, in particular decrease in levels of pulmonary lungfunction in children and adults with obstructive airways diseases* Increase in daily prevalence of respiratory symptoms in children and adults* Damage to, and morphological alteration of lung tissue* Risk of lung cancer correlated' with elevated long-term ambient concentrations of PMIO

39 S. VEDAL: Health Effects of Inhalablke Particles: Implications for British Columbia. Air resources Branch,Ministry of Environment, Lands and Parks. 1995.40 W.L. BEESON, D.E. ABBEY and S.F. KNUTSEN 1998. Long-term Concentrations of Ambient Air Pollutants andIncident Lung Cancer in California Adults. Results from the AHSMOG Study. Environmental Health Perspectives166(12): 813-822.

* Development of chronic bronchitis and predisposing factor to acute bacterial and viral bronchitisespecially in sensitive individuals. Aggravation of bronchial asthma, the late stages of chronic bronchitis, pulmonary emphysemaand cardio-vascular disease

6.3.1.6.2 Visibility degradationAs particulate matter (especially fine particulate matter) accumulate in the atmosphere, the particlesact to scatter and absorb light. The net effect is that the particulate matter can obscure the view,making it difficult for residents and tourists alike to "enjoy the scenery". Thus visibility is degradedobscuring vistas in a highly visible form of air pollution.

Too often, dark high optical density flue gas emissions violate opacity restrictions.

6.3.1.6.3 Soiling and Wasting EffectsWhen particulate matter falls out of the atmosphere, it can accumulate on cars, painted surfaces, andwhen falling in residential areas, will accumulate on laundry, and in the homes.Wastage of metal surfaces exposed to an atmosphere that swings from oxidising to reducing (soot isreducing) can also occur.

6.3.1.6.4 Intensity of Impacts

6.3.1.6.4.1 Ambient ConcentrationsIn terms of ambient concentrations in the Atmosphere, reference is made to the local MauritiusStandard41, that sets out the level of ambient concentrations for a given averaging period.They are given in Table 6.3.1.6.4.1.1 below. In the said table, Baseline data, it is recalled impliesambient conditions resulting from the operation of:* Union St-Aubin (USAB), La Baraque & MT-MD sugar factories concurrently with CTDS (coal)in the crop season;* CTDS (coal) alone in the inter-crop season


Table 6.3.1.6.4.1.1: Modification of Ambient PMI 0 Concentrations by CTSav P.S.

Maximum Ambient PM10 Concentrations (jigm/m3 )Averaging Period Mauritius Standard Baseline Data With CTSavInter-crop Season

24h 100 0.28 0.70

Crop Season24h 100 25.23 4.94

41 Government of Mauritius. Goverment Notice No 105 of 1998. Regulations made by the Minister under Section 35 ofEPA 1991.

6.3.1.6.4.2 Emission RatesThe impact of PMio generation may be assessed with reference to the emission rates of the powerunit and to the Emission Standards proposed for Mauritius and set out by World Bank.In Mauritius:* the proposed standard for emission of Particulate Matter is: 200mg/Nm 3* the proposed standard for opacity is RINGELMAN No2 or equivalent for not more than 5minutes in any period of lh.

Existing World Bank Guidelines set out:For plants smaller than 50MWe, the tolerable emission rate of Particulate Matter is 1OOmg/Nm 3. the tolerable ambient Particulate Matter concentration is 1 00tg/Nm3 annual geometric mean,500[tg/Nm3 maximum 24-h average.

The expected combined emission rates when all units are in concurrent operation either in the Inter-crop of in the Crop season are seen to stay below the emission standards for Mauritius.In fact, the burning of bagasse by the ESP-equipped CTSav Power Station, contributes significantlyto the reduction of ambient PM 1o concentrations that would otherwise be obtained from La Baraqueand MTMD during the crop season.

6.3.1.6.5 Mitigating measuresMitigating measures are not deemed necessary in as much as the CTSav power plant is concerned.

6.3.1.7 Impact of POP EmissionsPOP's will be taken as Dioxins (PCDD) and Furanes (PCDF).

Dioxins form part of the chlorinated polycyclic aromatic hydrocarbons group whose differentfamilies of compounds display very similar chemical structures (Dioxins, Furanes, PCB), thedifferent isomers provoking more or less the same toxic effects. So much so that the so-called"Dioxin equivalent" factor has been coined to measure the toxicity of each of these compounds,relatively to the most toxic of them, namely 2 3 8 tetrachlorodibenzo-p-dioxin (TCPP or SevesoDioxin), valued 1. WHO recommends this procedure since 1997 for 17 PCDD/PCDF isomers and12 PCB isomers.

These substances occur naturally in the environment, whenever events (volcano eruptions, forestfires, etc) occur, bringing together Cl and organic substances. Not to mention anthropic sourcessuch as incinerators, vehicles running on gasoline with lead content.Dioxins are persistent in the Environment and have the property to bio-accumulate in food chains.They are highly soluble in fats and this facilitates their absorption by digestion (60 to 90% of totalabsorption by living organisms).

6.3.1.7.1 Nature of Impacts

6.3.1.7.1.1 Non-cancerous EffectsThe following responses or reactions to CPAH have been observed:* Animal responses: loss of weight causing death, skin disorder similar to chloroacne, anomalousblood clotting, hormonal disorder, diminution of melatonine serum concentration, diminution ofA-vitamin stocks in liver, hyper cholesterol.* Human responses: the demonstrable effects are chloroacne under severe exposure as after theSeveso incident, alteration of liver enzymatic system, rise in gamma-GT, rise in alcalinetransaminases and phosphatases.

Consequences of environmental exposure to weak-to-average doses, have not so far beenestablished with certitude. No convincing demonstration has been tabled concerning effects on theimmune, humoral and cellular systems, disorders of neural transmission and increases incardiovascular risks, although these effects have been observed.Inasmuch as human reproduction is concerned, the conclusions arrived at in different studies onteratogenic and abortive effects of PCDD, do not really correlate. The aforesaid studies essentiallypoint to a higher incidence of malformation, still-births, miscarriages. Foetotoxic effects have beendemonstrated in cases of ingestion of PCDD in high doses (hyper-pigmentation of skin and gums,gum hypertrophy, slowing of in utero growth, persistent slowing of growth). Exposure to highPCDD doses has also been found to modify the genus ratio at birth, namely a relative augmentationof girls.

Finally anomalous psycho-motor development, persistent cognitive disorders, or neuromusculardisorders of a more transitory nature, have been observed by several authors, but some controversystill persists as to their conclusions (existence of confusing factors, co-exposures, or psychologicalparameters)

At current exposure level, risks of impairing the reproduction system and the psychomotordevelopment of children would be more preoccupying although they have not been formallydemonstrated.

6.3.1.7.1.2 Non-cancerous Tolerable DosesNo reference concentration is known to have been defined for Mauritius.Inasmuch as ingestion rates are concerned, the World Health Organisation (WHO) has estimatedTolerable Daily Doses (TDD) in regard of the systemic toxicity of PCDD and PCDF. These TDD'sare:* teratogenicity: lx 10-7 mg/kid* Foetotoxicity: lx 10-8 mg/k/d* Immunotoxicity: 3 x 1 0-10 mg/k/d* Susceptibility to viral infections: lx 10-8 mg/kld* endometriosis: 1.44 x I0O-' mg/k/d• impact on spermatogenesis: 6.4 x 10-8 mg/k/d* enzymatic induction: 3.5 x 10-9 mg/kid

In 1998, WHO defined a TDD of 4 x 10-9 mg/k/d, with a target of 1 x 10-9 mg/kid to be attained.

The TDD value retained for the CTBR in Reunion Island is l x 1 0-9 mg/kg/d, or I pg/kg/day.

6.3.1.7.1.3 Cancerous EffectsPCDD's are not mutagenic substances as they do not modify the cellular genome. But on cellsalready initiated (with modified genome) they would display a promoting activity in facilitating theexpression of the modified genome.

With animals, cancer sites induced by exposure to PCDD's are very variable according to species,which hinders transposition to humans. It would appear that the incidence of certain cancers(hormone-dependent cancers) decreases when exposure to dioxines is prior to exposure to thecancer initiators.

In humans, numerous studies have been conducted under diverse circumstances, the most reliablestudies concerning strong exposures and important latent periods:* professional exposures as in the Chemical Industry* accidental exposures, as at Seveso and spillage of highly contaminated products* war facts, as with the Orange Agent (in Viet-Nam), a herbicide highly contaminated with2,3,7,8 TCDD

Cancers of the naso-pharynx, lungs, kidney, stomach, bladder, skin, testicle, ovary, thyroid, brains,as well as leukemia, multiple myelomes, soft tissue sarcomes and non-hodgkinian lymphomes havebeen associated at least once with exposute to 2,3,7,8 TCDD.

Globally, therefore, WHO and CIRC have recently concluded that 2,3,7,8 TCDD is a certaincancerous agent for humans (Group 1), even though it may be a weak cancerous agent. OtherPCDD and PCDF are classified Group 3: non-classifiable agents.

6.3.1.7.1.4 Cancerous Threshold DosesTwo different points of view prevail presently: that of EPA (2000) and that of OMS.EPA suggests that PCDD's be considered as true cancerous agents therefore without criticalthreshold doses. In EPA (2000) an oral slope factor of 1 x 10-3 pgTEQ/kg/day has beenprovisionally defined.

OMS, on the other hand, adopts the view that PCDD's are not true or directly cancerous, but ratherpromoting agents in cancer genesis. The threshold dose would therefore be of the order of 6 x 10-9mg/kg/day and doses of I x 10-7 mg/kg/day (CPP 1998) would trigger cancers.Inasmuch as TCDD is concerned, threshold doses proposed by OEHHA are:* inhalation: 38x10-3 mg/m 3;* ingestion (oral slope factor): 130 000 mg/kg/day

Inasmuch as hexachlorodibenzo-p-dioxin (PCDD) is concerned, threshold doses proposed by EPAare:* inhalation: 1.3 ,ugm/m3 ;• ingestion (oral slope facor): 6.2 g.gm/kg/day

For the CTBR EIA, 0.1 3pg/kg/day was retained.

6.3.1.7.2 Intensity of Impact from Ambient PCDD/PCDF ConcentrationsIt is not possible to assess directly how the PCDD/PCDF ambient concentrations will be affected bythe operation of the CTSav power station, as no PCDD/PCDF data is known to exist for Mauritius.It is certain, however, that these pollutants have been produced in the past, during the burning ofcanes fields (analogous to forest fires reported in international literature) and also by the varioussugar factories, during the crop season.

The main change, of course is that whereas PCDD/PCDF could have been generated during thecrop season, it will be now generated throughout the year.

Maximum Ambient PCDD/F Concentrationsas per simulations (Rig/m 3)Averaging Period Baseline Data With CTSav

Inter-crop SeasonAnnual (xle-9) 1.06 0.74

Crop SeasonAnnual (xle-9) 0.001 0.06

The ISCST3 model has been used (without wet deposit effects) to estimate the ambientPCDD/PCDF concentrations resulting from the implementation of the CTSav Power Station. Theresults in the Table above, display very small concentrations, much smaller than those advocated inReunion Island for 1-hour sampling periods.

6.3.2 Pollution by Effluents from ProcessFrom the foregoing, process effluents will be produced at the rates and concentrations, detailed inTable 6.3.2.1.1 below.

6.3.2.1 The ImpactThe discharge of the Plant effluents in nature as irrigation water, will not contribute to increasingthe pollution level of the environmental waters. This can be appreciated in the said Table 6.3.2.1.1,with reference to the Recommendations for Quality Limits of Effluents to be discharged in variousReceiving Waters Standards proposed for Mauritius

6.3.2.2 Mitigating MeasuresFrom the comparison that can be made in aforesaid Table 6.3.2.1.1, if the CTSav effluents arecollected and treated to quality measured at CTBV, no mitigating will be necessary. The more sothat the treated effluents will be further diluted by river water supplied to the irrigation networks.

Table 6.3.2.1.1: Production Rate and Quality of CTSav Effluents comparedto Mandatory Quality for Discharges

Mandatory Effluent afterQuality Treatment

pH 5 - 9 9.49P.Free Alkalinity mg/C _ 30TDS_ mg/ 2 000 479Colour Pt.Co 149Chemical Oxygen Demand mgl/ 120 traceBiochemical Oxygen Demand m/C 40 NilConductivity iS/cm 633Chloride mg/e 99.1Total Suspended Solids mg/C 45 20Reactive Phosphorous mg/C 2.91Sulphates S04 mg/C 500 NilNitrates N03 mgN/t 20 1.5Available Chlorine mg/t 250

Total Chromium mg/C 0.10 NilHexavalent Chromium mg/t NilAnionic Detergents mg/R 5.0Oil in water mg/C 10.0 NilNitrite N02 mngC NilAluminium mg/t 5.0 NilCopper mg/C 0.20 NilNickel mg/C NilIron mg/t 5.00 NilZinc mg/C 2.0 0.01Potassium mg/t

Sodium mg/tTemperature

0 C 25 0CTurbidity 23Phosphate mg/t 0.3Sodium Adsorption Ratio

< 6

The concentrations in the last column 'Effluents after treatment', according to the Proponent,concern the totality of effluents downstream of the Power Plant, before being released to theirrigation circuits of the Sugar Estate.

6.3.3 Pollution by Process and DomesticWastes6.3.3.1 The ImpactThe wastes will be produced as a result of the operation of the Power Plant, and also owing to thepresence of Staff and Operators on Site.

With reference to § 3.9.2 of the foregoing, the rate of production of solid wastes and their naturecan be summarized in Table 6.3.3.1.1 below.

Table 6.3.3.1.1: Solid waste from Power PlantOrigin Type OutputTurbo Machinery . Hydrocarbon Mud negligible

Power Plant . Fly Ash 20 200 tons/year. Slag 18 160 tons/yearHuman Resources Domestic -10 tons/year

These wastes, in particular the hydrocarbon mud, will pollute the ground on Site and eventually thewater table.

6.3.3.2 Mitigating Measures

6.3.3.2.1 Fly AshThe disposal method proposed in § 3.5.4.2.1.2 of the foregoing, namely the recycling of fly ash as aconvenient and economic supplement to Portland cement in uses ranging from highway/civilengineering applications, to agricultural applications appears satisfactory.The incorporation of fly ash as an additive to Portland Cement is not in practice in Mauritius and ifthis re-cycling is not accepted by the local contractors, it will have to be disposed of, at a cost, innon-productive landfills.

6.3.3.2.2 SlagSlag can be conveniently and economically disposed of in highway/civil engineering applicationsdue to its physical and chemical characteristics and resistance to chemical attacks. The aboveremarks made above for fly ash also apply for slag.

6.3.4 Biological Pollution of Surface and Underground WaterThe Project will employ 40 persons, and assuming that the per capita daily water consumption is ofthe order of 5OL, to account for sanitary, messing, etc. the daily production of wastewater willamount to about 2m3.

The quality of the wastewater is typical of domestic sewerage and is described in Table 6.2.1.2.1[Typical domestic effluent composition at various stages of disposal] above, at production atvarious stages of disposal.

6.3.4.1 Nature of the ImpactNegative impacts on the local surface and underground waters may result from domestic effluents,if these are allowed to reach the local water table and surface waters with their inherent pollutionloads.

With reference to the Recommendations for Quality Limits of Effluents for discharge in the watertable or surface, discharge of untreated sewerage will not be allowed. This impact must therefore bemitigated.

6.3.4.2 Mitigating MeasuresThe simplest way of eliminating biological pollution by the Project would be to treat the sewerageproduced by means of a septic tank with the appropriate retention time and with correctlydimensioned and designed leaching fields. Thus the effluents ultimately released from the leachingfield will have the quality described in Table 6.2.1.2.1 above.

Although in theory, such an arrangement is deemed to work satisfactorily, yet, it is absolutelynecessary to ensure that:* the septic tank is properly dimensioned with respect to the population it is going to serve* the leaching field is likewise properly dimensioned and positioned* the system performance is monitored and de-sludging of the septic tanks is carried out as andwhen necessary

6.3.5 Noise from CTSav Power Plant6.3.5.1 Nature of ImpactNoise will be generated 24h per day on Site.

6.3.5.2 Intensity of ImpactThe noise field measurements made on the perimeter of a 200m radius circle around the 6OMWeCTBV power station have been extrapolated to the future CTSav Power Station as can be observedin Figure 6.3.5.2.1.

The bulk of the present residential settlements are at nearest some 800m from the CTSav locationand noise levels there, associated with the Power Station will be between 52dBA (at 400m from thePlant) and 46dBA (at 800m).

For Mauritius, the Legislation in vigour imposes the following Industrial Noise Exposure Limits:* From 07hOO to 21hOO: 6OdBA* From 21hOO to 07hOO: 55dBA

It may be concluded that no negative impact will result from noise generated by the Plant.However, this does not relieve the Proponent from ensuring that all usual noise-proofing measuresare taken with in particular:. Turbine/generator Couplings: Flexible couplings to dampen transmission of engine shafttorsional vibration

Piping Connections: Flexible hoses and bellows for connection to external piping networks

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6.3.6 Pollution by Hydrocarbon Wastes and SpillsWith reference to the foregoing, the potential sources of hydrocarbon pollution that can beidentified with respect to the processes and flows within the power station:• Lubricating oil freshly delivered by the supplier will be stored in a "intermediate storage tank"* Used lube oil from the plant lubricating circuit will be stored in a storage tank of appropriatecapacity

Hydrocarbon (lubricants, hydraulic fluid) spillage must be anticipated:* either of accidental nature, such as leaks from the storage tanks, delivery pipes* or as a result of servicing and maintenance operations to the plant components

6.3.6.1 The ImpactHydrocarbon spillage, if not controlled, will pollute the soil directly and eventually reach the watertable and surface waters. They can also be washed away during rain spells to load the Site run-offand as such, discharge into the drainage networks.

The hydrocarbon film, which will float on the water, may then be carried away by currents or underwave action to beaches.

6.3.6.2 Mitigating Measures(i) The delivery and storage of hydrocarbon products on Site shall be entrusted to a company,who is specialised with the handling and storage of hydrocarbons.(ii) Storage tanks and piping shall be manufactured to required dimensions in stainless steel andto SUPPLIERS standards, in order to obtain a quality and performance guarantee.(iii) The storage tanks shall be fitted with a base opening to remove the mud and water depositingat the bottom; de-watering and de-sludging will be carried out periodically by SUPPLIER.(iv) The steel storage tanks shall be built on a reinforced concrete base, fitted with an enclosingparapet of capacity equivalent to 110% maximum spillage and a sump where any leaks or spillagewould collect safely.

The used oil, oily water and sludge will be recuperated from their on-Site storage facilities by forbuming with bagasse.

6.3.7 Pollution by Loaded Storm runoff6.3.7.1 The ImpactThe Site being paved and occupied by buildings or water collecting structures like roofs, pavedareas, etc., there is a likelihood of storm water build-up contaminated with coal dust, hydrocarbonspillage from Lorries and other heavy vehicles on paved (asphalted) accesses and parking areas, etc.


The Site will be provided with a peripheral drain, to intercept all runoff. All loaded runoff, induced

by rainfall or not, will be intercepted, collected and treated before release to the environment.

The treatment process will involve placing a hydrocarbon separator, a mud/silt trap and trash rack in

the runoff collector prior to discharge to irrigation canals.

6.3.8 Increasing Occupancy of Quay Nol

6.3.8.1 Nature of the Impact

The operation of the Power Plant will imply a further increase in the occupancy of Quay No 1 thatcan be estimated on the basis of the following data communicated by the Proponent. For Raw

Sugar:* Annual tonnage of coal to be discharged: 125 000tons.* Expected coal handling rate in Port-Louis Harbour: - 7 000 tons/day• Individual cargo size to be discharged: 40 000tons.

Then:* Gross annual coal unloading time: 18-24 days* Frequency of coal carrier arrivals: 3 per annum* Duration of each carrier unloading: - 6 days.

It is therefore necessary to assess its present level of utilization. The aggregate Berth No 1Occupancy for the past five years is42:

Table 6.3.8.1.1: Measured historical utilization of Berth 1.

1994 1995 1996 1997 1998

Berth I Occupancy 60.5% 60.7% 67.7% 72.2% 73.2%

The weather downtime of Berth 1 (when wave heights exceed 0.5m) is estimated at 15 days p.a.4 3

With respect to historical situation, the discharging of coal at Berth 1 has already increased to copewith additional coal for FUEL and will also increase shortly to cope with the additional 100 000tons per annum fror CTDS. The discharging of a further 125 000 tons of coal per annum for theCTSav Power Station will therefore further increase:* the occupancy rate of Berth 1 towards its limits* the complexity of management of Berth 1


The Mauritius Ports Authority will be submitted with heavier discharging schedule in order toaccommodate the various users of Quay No 1.

42 Mauritius Ports Authority. Correspondence 24^ November 1999.43 Sir A. GIBB & Partners and RENDEL, PALMER & TRITON: Model Studies for the Proposed Mer RougeContainer Terminal, Feb. 1993.

For instance, coal operations having been successfully carried at Quay No2 in the past, this could beenvisaged anew, unless cement operations there excludes this possibility.

6.3.9 Risks with Strategic Coal StorageStorage conditions may imply more indirect impacts through risks than actual direct impacts.

6.3.9.1 Fire Risks

6.3.9.1.1 Origin and Mechanism of the Risk

These risks may result from spontaneous ignition (at temperatures between 50°C and 70°C) underexothermic reactions with atmospheric Oxygen, and whose rate depends inter alia upon:* The characteristics of the coal:

(i) contents in VS

(ii) contents in Sulphur pyrites (=:> SO4--)

(iii) the circulation of external air (hence renewed oxygen supply) into the coal stacks(iv) porosity

* ambient temperature, the rate of oxidation doubling with each 1 0°C rise in temperature* granulometry, the finer the grains, the larger the surface exposed to oxidation* ambient moisture content, inducing condensation and release of heat equivalent to latent heat of

vaporisation, of particular importance to the outer coal layers on view of its permeability toexternal air

6.3.9.1.2 Intensity of the Risk

The strategic coal storage proposed at the CTSav plant:• concerns RSA coal of the bituminous and low volatile sub-bituminous type, with an Ash Content

varying from 9.1 to 10.1% on dry basis• is of the unsorted mixed type* will be stored in shielded conditions* will be placed in compacted layers to reach a final stack height of 3m* will incorporate no devices facilitating the circulation of air inside it* will have infinite rotation period (relative to the usual few months)

Therefore, applying the BYSTRON & URBANSKI Method of Fire Risk assessment, the strategiccoal storage has a Fire Risk Index Zp = 1 1, i.e. a Medium Risk.

Mitigation measures are therefore necessary

6.3.9.1.3 Mitigating Measures

(i) Stock Temperature Monitoring

Temperature monitoring will be carried out frequently by trained personnel using thermometers atthe end of long probes for which access to the stacks must be provided through the protectiveshields and such that no external air circulation is favoured by such accesses. The results will be

logged in such a way as to provide a three-dimensional mapping of the temperature distribution ofthe strategic coal storage.

Should any heating be detected, oxidation reactions will be stopped by reducing the temperature ofthe stack. This is done by removing mechanically coal from the overheat zones and allowing it tocool down under ambient heat conditions. The heated coal may be spread out on a zone specificallyset aside for that purpose. Once in contact with the ambient air, the cooling process is initiated, arelatively rapid operation, the coal may be either placed back in the stack, or sent to the boiler to bereplaced by new coal.

The provision of stack temperature monitoring will lower the BYSTRON & URBANSKI Fire RiskIndex from Zp = I 1, to Zp = 1, i.e. a Low Risk.

(ii) Putting out Coal fires

Coal fires, as observed in stockpiles, are characterised by:* relatively short flames (20cm)* very localised fire seats, concerning at most a few dozens of kilograms of coal• very low propagation speeds, with virtually no risk of setting the whole stack in flames

Once discovered, they will be put out as follows:* mechanical removal of the incandescent coal. spreading of the incandescent coal in a thin layer on the spreading zone earmarked for that

purpose* putting out of the flames by ramming the coal with the bucket of the loader

Using water spraying as proposed by the Proponent is not advocated: it will:* increase the moisture content of the coal* provoke leaching of acid and heavy-metal loaded waters into the local water table

6.3.10 Extra Demand on Public Utilities and Infrastructure

6.3.10.1 Impact on CWAThe extra daily demand imposed on the regional potable water network will be of the order of a 3/4meters.

Considering the daily production of the regional system, about 7 000m3 /d, the impact of the extrademand is almost insignificant.

6.3.10.2 Impact on CEBThere will be no impact as the plant will supply CEB with electrical power.

6.3.11 Impact on Public Road Infrastructure

6.3.11.1 Origin and Mechanism of the ImpactThe increase in road traffic resulting from the implementation and operation of the CTSav PowerPlant at Savannah will be attributable essentially to the increase in circulation rates of the 30-toncoal trailer lorries (confirm capacity and daily rips).

The convergence of cane lorries to Savannah from the MTMD - Riche-en-Eau factory areas, as aconsequence of the centralization to Savannah is not considered here, as the Power Station is more aconsequence of the centralization policy. This issue has indeed been raised in the StakeholdersMeeting but it really has no bearing on the existence of CTSav.

The increase in circulation of 30-ton coal trailer lorries during some 5 months (January-June) will inturn induce the following impacts:* increase in atmospheric pollution (coal dust, NOx, C02, PM, SOx, ... )

* adding to traffic congestion, particularly along the Motorway at Port-Louis and eventually up tothe Phoenix Roundabout, depending upon the time of the day

6.3.11.2 Intensity of the ImpactsLet it be assumed that:* the annual consumption is about 2 x 14.108 T/h x 4 400h - 125 000 tons of coal per year* the duration of the annual operation period of 6 months* coal transportation will also take place on Sundays and holidays

Then, the additional trailer lorries circulating from the Coal Terminal to the CTSav Plant throughthe Motorway up to the Gros-Bois exit and along the Gros Bois - Savannah link will be of the orderof +24/day at most.

The motorway traffic is often saturated in and around Port-Louis and the coal lorries will but add tothat saturation, unless they avoid the saturation times.

6.3.12 Impacts of 66kV Transmission Line to Union Vale

6.3.12.1 Origin and Mechanism of the ImpactThe 66kV electric power transmission line in operation will generate an electric field and amagnetic field:* the electric field strength is dependent upon the voltage at which power is transmitted, therefore

66kV in the case of the CTSav Power Plant, with very little variation (<5%)* the magnetic field strength is a function of the current flowing in the transmission line, a quantity

that fluctuates considerably depending upon the load impose by customer demand.

Directly underneath the transmission line, the electric field strength to an observer on the ground isstrongly influenced by the height of the conductors above the ground, and therefore, is greatest atmid-span. The following impacts may be associated with EM fields.

6.3.13.1.1 Health Hazards

Power frequency magnetic fields induce currents in the body including the central nervous system.At levels much higher than those experienced by the general public, they can affect the control ofmovement and posture, memory, reasoning and visual processing.

Power frequency electric fields induce currents in the body and can also result in direct perceptioneffects due to alternating electric charge induced on the surface of the body causing for examplebody hair to vibrate. In addition, indirect effects such as microshocks can occur in strong electricfields through contact between a person and a conducting object.

Power lines can produce EMF strong enough to interfere with some models of pacemakers anddefibrillators.

6.3.13.1.2 Corona effect

When intense electric fields (- 30kV/cm peak in the air) occur at the surface of power lineconductors, in some circumstances (presence of water drops, snow flakes, and insects), ionizationand electrical breakdown of the air immediately surrounding the conductor may take place. This isknown as Corona Discharge. The St-Elm fire is an example. Corona is not normally encounteredon systems below - 200kV.

But when it occurs, it generates:* audible noise, particularly during rainy and foggy weather, and upon particulate deposits on the

transmission lines* Radio and TV interference

6.3.13.2 Probability and Magnitude of the Impact

Reference must be made to:* the magnitude of the electric field (kV/m) and of the magnetic field (in Gauss or the Tesla - 10

000 Gauss) that can be expected from the Savannah - Union Vale 66kV power transmission line* the presence of any exposed population

The Intensity of the Magnetic Field can be inferred from the figure below

EIA - CTSav: Construction and Operation of a 83.OMWPower Plant at La Baraque Page 69

75 kV j40 132 kV

66 kV

30

20

1 0

0-40 -20 0 20 40

Distance from centre line / m

The maximum intensity of the magnetic field will be of the order of 5jiT below the mid-span,

provided the transmission line is constructed as per Standard Specifications.

The maximum intensity of the electric field will be of the order of 1.6kV/m below the mid-span of

the transmission line.

Since there are no resident populations in the R.O.W. and the intensities of the MEF's are low,

impacts are likely to be insignificant.


With reference to the alignment of the 66KV transmission line as shown in figure 3.2.1.1, althoughthe line is scheduled through sugarcane fields, it is nevertheless recommended that the alignment beno less than 50m from any residential settlements along the main road.

Hence as soon as the transmission alignment is finalised and approved, no residential developmentshould be permitted within the said buffer zone.

6.3.13.4 Impacts during Installation of the transmission line

The transmission line as indicated previously will be installed in sugar cane fields. All the activitiesassociates with its installation will be mainly confined to the fields. Moreover the contractor will be

using the intemal roads within the cane fields and away from the residential areas. Hence the

impacts will be minimal.

6.4 Positive Economic Impacts

6.4.1 Creation of Direct New Jobs

6.4.1.1 At Construction Phase

The construction of the power plant will involve the participation of local contractors of varioustrades (welders, pipe fitters, mechanics, masons, electricians). Thus, for the two years during theconstruction will last, temporary jobs are expected.

6.4.1.2 At Operation Phase

The Project will create 40 direct new permanent jobs organized as follows:

The Power Plant* Plant Manager* Assistant Managers* Senior Engineers* Technicians and Quarter asters* High skill maintenance and process staff* OthersAdministrative* General Manager* Assistant GM* Senior Engineers* Accountants* Secretaries* Drivers

6.4.1.1 Generation of Indirect New Jobs

Besides the creation of direct permanent or temporary (2 years) employment, the Project willgenerate work for:* Commercial Banks* Insurance Companies* Consultancy firms. Accountants* Logistics companies engaged in transport, warehousing and distribution services.

6.4.2 Avoided Investment Costs to CEB

The implementation of the power station ultimately delivering 82.5MW to the national grid meansavoided Capital Investment costs to CEB.

The gross Foreign Exchange Earnings, during the construction period will accrue from the transferof funds for the construction of the project, amounting to EUR100 million.

From the EUR100 million, the cost of local contracting works, fabrication, civil works, willprobably amount to EUR60 million. After making allowances for FC for the importation ofequipment, material, etc, the corresponding net FC earnings will amount to EUR40 million.



Chapter 7: Environment Monitoring Plan

7.1 The Environmental Monitoring PlanThe Environmental Monitoring Plan (EMP) is in fact an integral part of the EnvironmentalManagement Plan that has been elaborated in detail in Chapter 6, to make sure that the requiredenvironmental objectives are attained.

For the purpose of the Environmental Management Plan, the EMP will aim at ascertaining that:* the mitigating measures proposed under the Environmental Plan are duly incorporated in the

Project Engineering Specifications and actually implemented* any impact that may still result from the way in which the Project is implemented and run is

addressed and mitigated by appropriate measures

The EMP submitted in conformity with the provision of Clause 7.1 Content of an EIA.

The Proponent, or his nominated Representative, will be responsible for the implementation of theEnvironmental Monitoring Plan that will be implemented during the Project Operation phases.

7.2 EMP at Construction PhaseWith reference to the foregoing, the Environmental Monitoring Plan recommended for the Projectin its Construction Phase can be planned as described hereunder in Table 7.2.1.

7.3 EMP at Operation PhaseWith reference to the foregoing, the Environmental Monitoring Plan recommended for the Projectin its Operation Phase can be planned as described hereunder in Table 7.2.2.

7.4 Development of Contingency PlansContingency plans, in connection with road transport of used hydrocarbons, have already beensubmitted by AZUR44 and approved by the Authorities.

It is expected that similar contingency plan have been prepared and submitted by the Coal Terminalresponsible for the road transport and delivery of coal to coal-fired power stations at Belle-Vue,F.U.E.L. and DRBC.

44 AZUR: Company responsible for the operation and recycling of used oil and other oily wastes in the Harbour

Table 7.2.1: Environmental Monitoring Plan at Construction Stage

ACTIVITY REQUIREMENTS PROCEDURE RESPONSIBILITYFollowing handing over, the Site Plan shall be established detailing

1.1 Detailed Site Plan the layout of Site facilities such as access points, temporary ablution Contractor's Representativeand sanitary facilities, stockpiling areas, storage of hazardousmaterials if any, earthmoving equipment, temporary technical yard

1.2 Site Fencing Site shall be properly fenced and its access controlled -Ditto-The heavy vehicle routes shall be identified and all necessary Police

1. Site Establishment & Clearance 1.3 Heavy vehicle routes Escort arrangements and Road Authority Clearance obtained in view -Ditto-

of importation of heavy and bulky equipment to Site

An estimate of daily potable and construction water requirementsshall be provided for the duration of the Construction Period

1.4 Provision of Services Likewise for electricity consumption -Ditto-Temporary ablution and sanitary facilities, appropriate wastecontainers shall be providedRemoval and disposal of sugar cane from Site after the issue of Land

1.5 Vegetation clearance Conversion and Re-zoning permits shall be to the approval of the -Ditto-Responsible Party, and the Sugar EstateAreas for the stockpiling of imported materials such as rock sand,topsoil, basalt aggregates must be carefully chosen to avoid

2.1 Stockpiled Material interfering with or contaminating Site drainage under rain storms. -Ditto-Stockpiled topsoil, and sand shall not be taller than 6m, covered orregularly dampened to avoid nuisance from wind-born dust

2. Materials Management 2.2 Storage and containmentof Hydrocarbon & Hazardous NOT APPLICABLEWastes

EIA - CTDS: Construction and Operation of a83. 0MW Power Plant. Page 73

Table 7.2.1 (continued): Environmental Monitoring Plan at Construction Stage

ACTIVITY REQUIREMENTS PROCEDURE RESPONSIBILITY

The Site is to be kept free of litter at all time. Food leftovers shall be3.1 Collection and disposal of packed in bins to be hauled by a nominated Solid Waste Operator.Domestic and Construction Construction wastes shall be stored in a demarcated area protected -Ditto-

Solid Waste from rain to prevent leachate running pending haulage to an approved3. Waste Management landfill.

Adequate toilet facilities shall be provided and sited with theEngineers approval far away from water courses. The facilities could

3.2 Sanitary facilities be a septic tank with a temporary leaching field, or of the 'chemical -Ditto-type' to be emptied periodically by specialised effluent tankers anddisposed at the Mare-Chicose treatment PlantHeavy earthmoving equipment shall be serviced on a suitable

4.1 Equipment Servicing temporary RC platform to fall within a collecting sump, and all used -Ditto-hydrocarbons shall thus be retrieved and disposed of in a landfill or abagasse furnace authorized for combustion of waste oilsThe nominated Representative of the Contractor shall submit monthly

4.2 EMP Reports reports to the Engineer who will verify the information -Ditto-

Complaints received regarding the construction activities on Site thatrelate to the Environment shall be recorded in a special designated

4. General 4.3 Complaints received register and the response noted with the date and the action taken. -Ditto-This record shall be submitted with the monthly EMP report and beavailable for inspection by the regulatory authorities.When heavy vehicles from Site have to access Public Roads, they

4.4 Mud Pollution of Public shall not be allowed to spread mud from Site on the said Public -Ditto-Roads Roads which shall be maintained free of mud at all times by a gang

specially affected to that taskAs soon as possible after the Contractor has taken possession of Sitewater samples shall be collected from Ruisseau Kennel, River Tabac,

4.5 Baseline Data and Ruisseau Vinay and the samples analyzed to supplement the -Ditto-Acquisition Baseline Data to the Report.

EIA - CTDS: Construction and Operation of a 83.OMW Power Plant Page 74

Table 7.2.2: Environmental Monitoring Plan at Operation Stage


Hazardous material such as lead accumulators for the DC units, shall1.1 Storage of Hazardous be stored and serviced in a demarcated area, fenced and of restricted -The Plant Operator-Material access.

All hydrocarbon containers shall be stored within a suitable1. Materials Management reinforced-concrete area surrounded by a containment (bunded) wall

1.2 Storage of Hydrocarbon to a capacity of at least 1 10% of that of the containers. -Ditto-A regular hydrocarbon material balance shall be kept to equate supplyto usage and detect all losses from the storage tanks.

Systematic temperature monitoring of the Strategic Coal Storage shall1.3 Temperature Monitoring be carried out by means of probe-mounted thermometers and water-of Strategic Coal Storage tight ports shall be built into the Storage Shield for that purpose, with -Ditto-

facilities for inhibiting all external air intrusion when the probes arenot in place.Domestic wastes shall be packed in bins to be hauled to sanitarylandfill by a nominated Solid Waste Operator.

2.1 Domestic Waste -Ditto-

* A regular battery count shall be kept to equate operational units todiscarded ones and ensure that the totality of the latter are hauledto safe disposal

* All hydrocarbon wastes - used oil from Generator Set, storage2. Waste Management 2.2 Hazardous Wastes tank sludge, 'oily waters', shall be removed by the nominated

Supplier team qualified for such tasks, for safe disposal by AZUR -Ditto-

EIA - CTDS: Construction and Operation of a83.OMW Power Plant. Page 75

Table 7.2.2 (continued): Environmental Monitoring Plan at Operation Stage


Fly ashes from the ESP will be first moistened to - 15% humidity and2.3 Collection of Combustion then transported in covered trucks for disposal in landfillsWastes Furnace slag, more stable by nature, shall be collected and stored in -Ditto-

open bins pending disposal(i) Fly ashes:* Fly ash can either be delivered in their covered bins to Building

Companies for incorporation in concrete as an additive to Portlandcement in conformity with ruling Technical Specification, or -Ditto-

2.4 Disposal of Combustion moistened to - 15%, transported in covered trucks for disposal in

Wastes land filling sites with the approval of the Landfill Management(ii) Slag:

2. Waste Management * Slag can be used either for land filling, incorporated with concrete

or in the construction of road bases and sub-bases

Resins used in the Demineralization Plant are regenerated in brine

2.5 Collection and Disposal which is neutralized in the neutralization pit before being mixed with

of Demin Plant brine and other liquid effluents. -Ditto-

resins Used resins will be burnt in the furnaceCoal dust from the coal reception and conditioning unit floor

2.6 Collection and Disposal washings will be recuperated at the settling pond, dried and disposedof coal dust of in landfill

3. Air Quality Monitoring 3.1 Stack Emissions Monitoring of key parameters such as PMIO, CO, C02, S02 etc. at

least once each during the crop and intercrop seasons

3.2 Ambient Air Quality Analysis of ambient S02 concentrations using a HVAS within aradius of 1 500m around the Power Station, taking into account winddirection.

EIA - CTDS: Construction and Operation of a 83.0MW Power Plant Page 76

Table 7.2.2 (continued): Environmental Monitoring Plan at Operation Stage

ACTIVITY REQUIREMENTS PROCEDURE RESPONSIBILITYThe nominated Representative of the Plant Owner and Operator shall

4.1 EMP Reports submit monthly reports to the Department of Environment as -Ditto-requestedComplaints received regarding the construction activities on Site thatrelate to the Environment shall be recorded in a special designated

4.2 Complaints received register and the response noted with the date and the action taken. -Ditto-This record shall be submitted with the monthly EMP report and be

4. General available for inspection by the regulatory authorities.When heavy vehicles from Site have to access Public Roads, they

4.3 Mud Pollution of Public shall not be allowed to spread mud from Site on the said Public -Ditto-Roads Roads which shall be maintained free of mud at all times by a gang

specially affected to that taskWhen the Plant shall be in operation, water samples shall be collected

4.4 Baseline Data at the point of discharge of ALL Effluents from the Power Station,Acquisition and the samples analyzed to provide Baseline Data to the Authorities. -Ditto-



Chapter 8: Conclusions

8.1 In January 2004 the Central Electricity Board (CEB) launched a tender for the purchase andimportation of electrical power on the National Grid. Compagnie Thermique de Savannah LtWe(hereinafter referred to as CTSav), a public liability societe company duly registered in Mauritiussubmitted an offer based on the implementation and operation of a dual coal/bagasse-fired2x41.5MW steam power plant at La Baraque, and the construction of a 66kV transmission linkfrom La Baraque to Union Vale.

8.2 CTSav's offer has subsequently been retained. A Power Purchase Agreement (PPA) has beensubstantially negotiated and concluded with the CEB on the 18 February 2005 for the sale to CEBof about of 335GWhE per year, power importation to the National Grid being modulated in functionof customer demand (expected average production 335GWhE per year).

8.3 The Project will be located next to the La Baraque Sugar Factory in the district of Grand-Port -Savane, on a plot of land owned by Savannah Sugar Estate, and released for the Project asauthenticated by a notary public. The land hitherto under cane, CTSav has submitted for thenecessary Re-zoning and Land Conversion Permit.

8.4 The proposed Power Station has been the object of an Environmental Impact Assessment(EIA), a mandatory exercise in conformity with the provisions of the Environment Protection Act2002 (Mauritius).

8.5 Negative Impacts have been identified with the operation of the Power Plant. They are mainlyassociated with:* Atmospheric emissions that will decrease the ambient air quality in the region. In particular the

ambient level of Sulphur dioxide during the inter crop season when CTSav will operate on coalas combustible.

* Other coal/bagasse combustion products, and ashes (bottom ash or slag, and fly ashes)* Liquid effluents such as resin wash waters from the boiler water demineralization unit, oily and

dust contaminated waters from the Plant* Hydrocarbon wastes (lube oil sludge, used lube oils) from the Planta On-site storage of coal• Intensification of lorry traffic, noise and atmospheric emissions from road transportation of coal

8.6 The negative impacts that could result there from can be effectively mitigated by theimplementation of the following measures:* Increasing the stack gas ejection velocity in coal-combustion mode from 10 m/s to not lower

than 20m/s susceptible of enhancing atmospheric dispersion of S02* Collection and pretreatment of the liquid effluents to the standard prescribed for their discharge

by the appropriate Regulations

* Prevention and/ or containment of leachate from the coal stock piles* Prevention and fighting of fires originating spontaneously from the strategy coal storage* Collection of fly ashes for eventual incorporation in concrete as per appropriate technical

specifications, and in agreement with Construction Firms* Collection of slag and its disposal by incorporation in civil engineering structures as per

Standard Specifications, or in a landfill* Neutralisation of effluents from the demineralization plant and their reuse for irrigation.

8.7 Positive Impacts are basically of socio-economic nature. They will result from inter alia:• Availability at avoided cost to CEB, of a 83.OMWE net guaranteed production capacity* A more efficient exploitation of bagasse, the familiar renewable biomass source of energy* The provision of temporary employment to various professional trades during construction and

permanent employment thereafter during operation



APPENDIX A - Site Ownership

ATTEST&TI,N

Ceci est une attcstatior tzon a lefluct que Cvmnpagnic Suairrc'rHE

SAVANNAH SUGAR ESTAI'ES COMPANY LMTED' a, aux tcnicsd(un actc reCu ?ar Me. Rent* Maigrot, aincien notairc, lc vingt

quatre Novebrc nrml ncuf cent quarante quatre, eiregiratt' au RegC 205 No,4493 ct transcrLt au Vol.487 NoA48 acquis de Il

Cornpagnic Savinia Limitcd cntrc uu-et: bieu,, Ic buen bi-aprntd6crit,

CHAITRE I LA DARAQUV

La propriJlW &rigcc en suCrcnc connuc oous le no:n de "La BarutQuc",nituec au quarticr du Grand Port d'une contenan1ce de MILLE SOIXANTE

QUATORZE ARPENTS SOIXANTE TREIZE PERCHES.

Port Louis, lie Mouricc, cc s:x Juillet de I'an deux nullc cinq.-

L?7 THE SAVANNAH SUGAR ESTATESLI L COUPANT LIMITED

ro WHOM IF MAY (OrNC LRK

Following the Power Purchaw Agrecicnit signed betwccn Compagnme Tlierniquc deSavannah (CTSav) and The Central Elcirricity Board [CEB] on tIc 18t of ebrwiavy 2005.thc ncw coalbagasse power plant will bc consucicd on the choscn site at La Baraquc. Thsite of an extcnt of 4 683 hcctarcs will bc cxciscd from a plot of land of 1074 A 73 p as perTV 487 No 48 i:. situated at La Bquc and belon_; to The Savan:nah Sugar Estates Co. Ltd.as aultenticated by the ccnrirtcatc drawn rfor that purpose, by notary pLblic Mc PicrrcMonlocch io.

This is to conswm that the prescnt owner, 1Thc Savannah Sugar EsiatrG Co Ltd, has relta'icdthc land to ClSav fhr the purpose of constucling a coalb;aigsc pov%c, plarnt on the site.

The Savannah Sugar Eutrts Co Ltd. also confirrns that it has alrcady granted thei niccssaryway leave for the crwtion of the nccct-sry 66 KV lincs frm the sitc to the CEB Llnion-Visub-station on the land belonging eo the company

T*[E SAVANNA N I SUCGAR ESTATES CO. Lil Di

7".- i-ww:^,a Clo'ba r 1 loiwssoEie 'S-lC$'b,,.tt- -rrit- 3; : :; s-2.tl .;oz5lU -- - ¢ -lfJ,* 4 -- 4VIRC.". !



APPENDIX B - Ambient Air Quality Modelling


at Savannah


Ambient Air Quality Simulations

Baseline Data - Crop Season

Sources: Savannah S.EUnion Saint Aubin S.EMon Tresor Mon Desert S.ECentrale Thermique du Sud

-c \o- ~~~ ~ L P.'',-L ( A <-

BEM EN

S .. .

G II

". N

.. )y .- LOI -, -~/

PO WLR R PLA

Range Beg. Range EndColor (pg/m3) (;.g/m3)

0 1 51 5 303 0 4545 6060 7575 90

1095° 12°0 BASELINE DATA - Crop Seasor135 ISO Ambient Pollutant: CO

-- 160 180 Averaging Time: I HOUR-t2 2190 225 Standard Maximum: 25000Fug/m'

N225

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIEN-I- A-IR QUALITIY ()N SI TE - Polar Distribution of Carbon Monoxide Concentration

S.l.G.M.A. - Ove Arup & Partners -Associated Consulting Engineers - Port Louis - MAURITIUS

II.JNEM4ACNI4N

X X .i ' Fgn--. MN DESERCA RCBIEAtJNt,

C'I

11~ LA PALLE

MALAK

! - .. t

-,t

rA,

Range Beg Range EndColor (.Lg/m 3)(1O-B) (Ilg/m3)(1O8)

0.0 2.52.5 5.05.0 7.57.5 10.0

10.0 12.512.5 15.015S.0 17.5 BSLN175 20.0 BASELINE DATA - Crop Season20.0 22.5Poltn22'5 25.0 Ambient Pollutant: PCDD25.0 27.5275. 30°0 Averaging Time: 1 HOUR,7 30.0 32.532.5 35.035 0 37.5- >37.5

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SI TE - Poiar Distribution of Dioxine Concentration

S.I.G.MA. - Ove Aup & Partners - Assodated Consulting Engineers - Port Louis - MAURITIUS

MAEN-

L- CARAaEMa

.N 'I* E- -MON OES.S

'''-CRRLA \Ast\. lAr - kLA FARM

L \ ,LAKCff

CPA CARREAU

l -tx - SAVANNp

CARO1 '-

/ -

Range Beg. Range EndColor (Pg/r 3) (tg/m

3)0.00 0.750.75 1.501.50 2.25225 3.003.00 3.753.75 4.50

45.2 6.00 BASELINE DATA - Crop Seasor4.250 5.25ro6.00 6.757,So 7'5°0 Ambient Pollutant: NO)7.50 a.25

9080 900 Averaging Time: 24 HOURK9.75 10.50 Standard Maximum: 200Ig/rmn10.50 11.25

CONSTRUCTION & OPERATION OF A 83MW COALIBAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALIT ON SITE - Polar Distribution of Nitrogen Dioxide Concentration

S. I.G.MA. - Ove Arup & Partners -Assodated Csuflng Erginei -Port Louis -MAURITIUS

-, ' CSARRMo rwSNoJ. -TW -ML mKNF.BN. ~MON M

IAFIJ. N. (} '\ \,l, A-F)

CAREIAI

LA PALE

SVANNAH

* / /

1KPOWER IVT

Range Beg. Range EndColor (pg/m

3) (AgImr)

0 22 44 66 88 10

10 1212 14 BASELINE DATA- Crop Season14 16BAEIEDT-CrpSao

16 1818 20 Ambient Pollutant: PM1 C20 2222 24 Averaging Time: 24 HOURS. 24 26

26 30 Standard Maximum : 1 OOg/m3>30

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBiENT AIR QUALITY ON Si TE -Polar Distribution of Particulate Concentration

S.I.G.M - Ove Anup & Parers -Associated Consulting Enginerrs - Port Louis - MAURITIUS

o' - \-. CAMA CFAts5N0Fi

.' 0 rRESO

I ThOISBiQU MON DESER

-' L M>A -.1AJ,wO

C AA'EAU

L L.AA AOf

\ 'o ^POW RPAANT

Rtange Beg. Range EndColor (LWm/3) (4g/M 3)

0 1010 2020 3030 4040 5050 60

70 so BASELINE DATA - Crop Seasor100 110 Ambient Pollutant: SO:110 120 Averaging Time: 1 HOUR120 130

140 140 Standard Maximum : 350p,g/m-,

CONSTRUCTION & OPERATION OF A 83MW COALUBAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY UN SITE - Polar Distribution of Suiphur Dioxide Concentration

__S.I.G.MA.- Ove Arup & Partwes - Assoclated Consulring Enginmeer - Port Louils - MAURITIUS

TUfl4s BOUWiQuE O TRESOMONODESER

~CAWtAU]IAPAIJ

I NI

LApo;wN

Range Beg. Range En

Color (jig.mn) (gg'm,)0.0 1.51.5 3.03.0 4.54.5 6.06.0 7.57.5 9.09.0 10.5-CrpSao

Ins5 12.0 BASELINE DATA-CrpSao12.0 13.,5Poltn13.5 1s.0 Ambient Pluat O15.0 16.516.,5 lao Averaging Time: 24 HOURS1980 21.0 Standard Maximum :200pg/m221.0 22.5

CONSTRUCTION & OPERATION OF A 83MW COALIBAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENTI AIR QUALITY' ON SITE - Polar Distribution of Sulphur Dioxide Concentration

___ __ S.ILG.MA. - Ove Arup & Patrters - Associated Consulting Engineems - Port Louis - MAURITIUS


at Savannah



Baseline Data - InterCrop Season

Source: Centrale Thermique du Sud

tE a.-

C AMFlA,ISNOIJF

-- -

-

BouTwMON TUSMON DESER

I. -.

B. RageCAEE

Coo ((m3 -'A / c

I. MALAXORT

-I~

0 11 22 33 44 5

5 6

7 8 BASELINE Ra- End/Ambient3Pollutant: C10 11

*1 12 AveragingTime :1 HOUR13 14 Standard Maximum: 25000

14 IS

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRiED POWER PLANT AT SAVANNAHAMBIENT AIR QUALTY ON SITE - Polar Distribution of Carbon Monoxide Concentration

-- SIGMA. - Ove Aiup 8 Partners - Associaed Consulting Engineers - Port Louis - MAUeRITIUS - H

88 \ WXi i.- 4 tMON DEE

MALAKOFF%

X~>- /,\I t'-'>

CAW CAR M VE'

WPnE -L W.,

. . N .

Range Beg. Range EndColor (pg/m3)(109 (A.g/M3)(1M8)

O.OS 0.100.110 0.150 15 0.200 20 0.250 .25 0.30

°.'35° 0'30 BASELINE DATA - Intercrop Seasoro0.45 o°:ss Ambient Pollutant: PCDC

- - 55 065°AveragingTime: 1 HOUF0.65 0.70

-;'. 0.70 0.75;-0.75

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALiTY ON SITE - Poiar Distributon of Dioxine Concentration

S.I.G.MA. - Ove AmJp & ParUierS - Associated Consultirng Engineem - Port Louis - MAURITIUS

ESNOUF A

- NO4VALEThOIS SOn7QUE 2 MON TRESO

MON DESEE

*,~ c-' C4> . .

I -. * PMAAKOWEr

LE BOUCOIO

LA== SA VANN /OJFL

CANO

Range Beg. Range EndColor (pg/m3) (g/nm

3)

0.0 0.50.5 1.01.0 1.51.5 2.02.0 2.52.5 3.03.0 3.535° 4.'0 BASELINE DATA - Intercrop Seasor4.0 4.54.5 5.0 Ambient Pollutant: NO).5.0 5.5

5.05 6.5 Averaging Time: 24 HOURS70 7.5 Standard Maximum: 2OOpg/m2>17.5

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SITE - Polar Distribution of Nitrogen Dioxide Concentration

S. I.G.MA - Ove Anup & Partners - Assocdated Consuling Enginrs - Port Louis - MAURITIUS

EN

ESNOUF

l\ - ''' O'

TWS SUTpixMON TRESCMON DESEE

CARRtEALA PALE

A~~~I &W RA ? -'-UECAAREA

Range Beg. Range EndColor (plg/m3) (ig/m 5)

0.0 0.50.5 1.01.0 1.51.5 2.02.0 2.525 3.03.0 3.05AA

'-'-Sao3.5 40 BASELINE DATA - Intercrop Seasor4.0 4.54.5 5.0 Ambient Pollutant: PM1(5.0 5.5

-. '-0 5.50 6.0 Averaging Time: 24 HOUR!6.0 65

7.0W 6.5 7.5 Standard Maximum: 100,ig/m:>75.

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIRl QUALIFY ON SITE - Polar Distribution of Particulate Concentration

S.l.G.MA. - Ove Arup & Partners - Associad Consurtng Engineems - Port Louis - MAURITIUS-

-3s ) -- gO -0

-~~O -\L

S FICAAMAFEAUI

..

N - UN0I.1

MALAXOW

L --'S

010

-VV

'sn-

Range Beg. Range EndColor (jgg/m 31) (Aig.m 3J

0 1010 2020 3030 4040 5050 6070 70 BSLN670 0 BASELINE DATA - Intercrop Seasoro0 90 Ambient Pollutant: SO,900 100

110 120 Averaging Time:1 HOUR; 'r~ i120 130

140 140 Standard Maximum: 350lig/m'

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALI I Y ON SI E - Polar Distribution of Suiphur Dioxide Concentration

S.I.G.M.A. - Ove Arup & Parters - Assodated Consulirng Engireers - Port Louis - MAURITIUS


at Savannah



Centrale Thermique Savannah Operational - Crop Season

Sources: Union Saint Aubin S.ECentrale Thermnique du SudCentrale Thermique Savannah (Bagasse)

IROIS /auflQqjs 'MON DESEC

__d" T.b

LE BOUO34O

Color (ligm 3 (g/n 3

\ \ne-9 > 2- . > \4 g A\VA NNAH-) \ ff X 2 WER PLANTi

Rag,e. Rag End

Color (pg/m3) (jig/n3)

075 75

150 150225 225300 300375 375

545 525 CTSav OPERATIONAL- Crop Seasor600 600675 675 Ambient Pollutant: CC750 750825 825 Averaging Time: 1 HOUF975 975

1050 150 Standard Maximum: 25000g/m:>1 125 1125

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SITE - Polar Distribution of Carbon Monoxide Concentration

S.I.G.M.A. - Ove Arup & Parblers -Assodated Consulting Engineers - Port Louils - MAURITIUS

MALNON0,

f %MON DESER

LC.. A PAIJJ

i AMMAg00

N ~CARREALJ

~' ,

Range Beg. Range End

ColorLJ LE/r3(18

(g/L3)(l0

0.00 1.251.25 2.502.50 3.753.75 5.005.00 6.256.25 7.50

1000 1°°25°CTSav OPERATIONAL - Crop Season10.0 11.25°m in Pollutant:P D

,-. 13.5o 15.2°S Averaging Time: :1 HOUR16.25 17.501 7.50 1 8.75

a.snE

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIEN T AIR QUAL:I IY U7N Si TE - Polar Distribution of Dioxine Concentration

SolMr.gM Ap1&8e - osltEs RITIUS --

ciqv

TKO MON TRE5CMON DESEI

CAMtEAk 3LA PALLE

N ~TA

CA1 (M

LEBOUCHMI

t ARRA(M

/

Range Beg. Range EndColor (1Ag/m3) (g/m

3)

0.0 1.51.5 3.03.0 4.54.5 6.06.0 7.57.5 9.09.0 10.5

105. 1230 CTSav OPERATIONAL -Crop Seasor13.5 15.0 Ambient Pollutant: NO)15.0 16.5165 180 Averaging Time: 24 HOUR!18.0 19.519 5 21.02190 22.5 Standard Maximum: 200pg/m~>22.5

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBiEN T AiR QUALi Y uN SITE - Polar Distribution of Nitrogen Dioxide Concentration

SIGMA. - Ove Arup & ParIers - Assodated Consulting Engineers - Port Louis - MAURITIUS

/~~~. *. C EAT '.- ' , i0U

7,-~ WaNJJ i-.-' XA

1306m 3OfQl . ~MON TRES

MON Du5

CAPAIIE

.-

(~

Li DDUO40/

( -

Range Beg. Range EndColor (g±/m

3) (Rigm')

0.00 0.250.25 0.500.50 0.750.75 1.001.00 1.251.25 1.50

1.7°5 2.00 CTSav OPERATIONAL - Crop Seasor22°S 2.50 Ambient Pollutant: PM1 C257°5 3.00o Averaging Time : 24 HOLJR'txr.--< 3325° 3.520Sadr

ainm 01gm' f4 3.250 3.7503.03.75 Sadr aiu:1Opgm-

.375

CONSTRUCTION & OPE ION OF A 83MW COALAGASSE-FED POWR PLANT AT SAVANNAMBIENT AiR QUALITY ON SiT E - Polar D)istribution of Particulate Concentration

S.lG.MA. - Ove Arup & Partners - Associatd Consultng Engineers - Part Louis - MAURITIUS

-~~~~O E - --- ---T

MA 4E%

N, UldION~MJ

TRNS BoT1QIu MON TRESOMON DOEE

L ~A PALLE

MiALAKcOR '1%~

CAMP CAU4

LEU BOUO34OFN

[ L-5 A|& VANNPs,Qt-,, '- \ % ,\ 5POWER PLANf\ '--

10 2 ,)

, - 11-

..

20 3 0

Range Beg. Range EndColor ("g/m3

) (#3

0 1010 2020 3030 4040 5050 60

760 8° CTSav OPERATIONAL - Crop Seasor90 100 Ambient Pollutant: SO;900 100

100 110 Averaging Time: I HOUR120 130

140 140 Standard Maximum: 350,ug/m"->150

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SITE - Polar Distribution of Sulphur Dioxide Concentration

S. I.G.M A. - Ove Arup & Partners - Assocated Consulting Enginoers - Port Louis - MAURITIUS


at Savannah



Centrale Thermique Savannah Operational - InterCrop Season

Sources: Centrale Thermique du SudCentrale Thermique Savannah (Coal)

MAtCNfg 4

-, CARRLVAb!SNOU,0

T hO nISBOUIQF MON TRESO

L 1 -EEA MON DESER-, a : ULA PAW

MAJ-''-'

/ ~CAEA4J

RangeL

BeOURage En

SAVMA

Range Heg. Range EndColor (Ag/mi) (Ag/m

3)

0.0 1.51.5 3.03.0 4.54.5 6.06.0 7.57.5 9.0

19.0 13°.5 CrSav OPERATIONAL - Intercrop Seasor13.5 15.0 Ambient Pollutant: CC15.0 16.516.5 19.0 Averaging Time: 1 HOUR18.0 19.519.5 21.021.0 22.5 Standard Maximum: 25000I.g/m!>22.5

F CONSTRUCTION & OPERATION OF A 83MW COALIBAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SITE - Polar Distribution of Carbon Monoxide ConcentrationL S. I .G.MA. - Ove Arup & Parblers - Associated Consutrng Engineers - Port Louis - MAURITIUS

A-- -

TROI -OUNQU MON- rRE" .t -o ;'0X- REAIJ,-,

N4 ,

LA PALJ NOU

ff~ UMO' -

- -- f

Range Be&1U R EndE!O

BIN sn-E.

Color pm)19(m31)0.00 0.150.15 0.300.30 0.450.45 0.600.60 0.750.75 0.90

1°905 t205 CrSav OPERATIONAL - Intercrop Seasor1 350 1.65° Ambient Pollutant: PCDC1.65 1L80 AveragingTime: I HOUF0.95 0.102.10 2.25

>2.25

CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SITE - Polar Distrlbut-ion of D)ioxine Concentration

-- -S. I.G.M.A. - Ove Arup 8 Partners -Associated Conulting9 Engineers - Port Louls - MAURITIUS

- c ESNOUTU.a 'U Q- MON TRES

MON DESER

MNEO d.-

SS V v --- T.

CCARREAU

LA PALLEJ4O

,1 '' S- SAVISA

POWER PLANT

U v

J

Range Beg. Range EndColor (pgI/m

3) (iglmr

3)

01 2

2 33 44 55 66 77 8CTSav

OPERATIONAL - Intercrop SeasonH 10 Ambient Pollutant: NOx10 11

11 12 Averaging Time: 24 HOURS12 1314 14 Standard Maximum: 200pg/m3- >15

CONSTRUCTION & OPERATION OF A 83MW COAIJBAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SITE - Polar Distribution of Nitrogen Dioxide ConcentrationLrS.I.G.MA. - Ove Arup & Parters - Associated Consulting Engineers - Port Louis - MAURITIUS

,. /

iuces Wtni~w *' UM0NALr-MN 1CS

I suQjE MON TREEC

"N

T%

ACA0

RanBe B;eg. Range EndColor (I.tg/m3) (jig/rn)

0.05 0.100.10 0.150.15 0.20

- 0.35 0.400.40 0.45

0.45° 0.450 Ambient Pollutant: PM1 C0.50 0.55

-0.55 0.60 AveragingTime:24 HOURSf3,* 0.60 0.65

0jZtzoE o65 0.705 Standard Maximum: 1 00 jI/rn- >0.75

L CONSTRUCTION & OPERATION OF A 83M COABAGASSE-FLRED POWER PLANT AT SAVANNAH# AMBIENT AIR QUALITY ON SITE - Poiar Distribution of Particulate ConcentrationS.I.G.MA. - Ove ArUp & Pares- Associatso Consulting Engineers - Port Louis - MAUJRITIUS__

B.CRA NOIg (TRI Bouqu X 'slA '

/ M; \"ON MR- N UAPALLI

NIA 'I

00U0401.J'

- -

Range Beg. Range EndColor (jig/rn3) (1g8/m3)

20 40°40 6060 8080 100

100 120120 140Inero140 16 ~~CTSav OPERATIONAL - ItropSeason

200 220o Ambient Pollutant : S02-AveragingTlime: 1 HOUR- ,2808 300 StnadMaximum:30gm

| CONSTRUCTION & OPERATION OF A 83MW COAL/BAGASSE-FIRED POWER PLANT AT SAVANNAHAMBIENT AIR QUALITY ON SITE - Polar Distribution of Sulphur Dioxide Concentration

SITE

__ _ _ ... M.- Ov Aup&Pites- socae Cnu~n ngnes ot ois-M URLU


-U-SavannahEnvironmemaImpact Assessment


Pollutant Concentration at Discreet Receptorsand Maximum Concentration

Pollutant Concentration (gg/lr 3) - Baseline Crop Season

Relativr Location S02 NOX co Doixine sx lc-9) P 10I (nI y (m) Dist (rnl Dlrect (deg) lbr 24hr Annual 24hr Ihr Ihl 24hr Annual 24hrHospital -A -256.16 276.64 377 317.2 92.4 6.9 0.09 4.7 67.0 14.1 2.2 0.24 6.1Police Sn I/ Post Ofrice - B -651.21 393 77 761 301 2 102 0 7 3 0 18 5 0 160.6 28 0 5 5 0 73 17 0Mosque / Temple / Market - C -695.99 305.55 760 293.7 100.8 6.7 0.20 4.9 164.2 28.3 5.2 0.80 17.8School - D -921.13 276 14 962 286.7 102 9 7.4 0.24 4 9 1672 290 5.7 0 97 '0 1St Francois Xavier RC Church - E -817.51 95.86 823 276.7 101.6 7.3 0.24 5.4 169.2 29.3 5.8 0.96 20.7Health Centre - F -984.23 -135 87 994 262 1 89.4 8. 1 0 26 5.9 160.3 28.3 6 9 1 02 23 8Temples / Village Hall -G -1113.4 113.46 1119 275.8 100.9 7.1 0.25 5.1 155.1 27.1 6.3 1.01 19.7Communuv Cenire- H -1137 7 -284.19 1173 2S6.0 79.5 8 0 024 5 7 156.4 28 1 64 0 92 21 9School -I -869.1 -302.09 920 250.8 59.1 7.7 0.22 5.4 163.3 29.5 6.4 0.82 21.0Mosqu- -J 1082.7 -537 12 1209 243 6 56.8 6.6 0 21 5 4 150.7 27.5 60 0 74 21 1Temple - K -894.46 -822.2 1215 227.4 57.8 6.5 0.16 5.0 146.9 26.9 5.9 0.50 18.9Cemetery - L -691.56 -984.82 1203 215.1 57 1 6 4 0.10 4.6 139 9 25 6 4 8 0 31 12.6Temple / Village Hall - M -820.42 -1152.7 1415 215.4 53.2 6.6 0.09 4.8 138.4 25.5 4.5 0.31 12.0IMaikel -N -721.97 -1254 1447 20991 56 2 6 1 0.0W1 4 6 131.9 244 4 2 0 25 10 3

Pollutant Concentration (itg/m3) - Baseline Intercrop Season

Relative Location S02 N_ON CO Diovine lx e-9 P131It1x(m)j y(m)| Dist Im) Direct (deg) Ihr 24hr| Annual 24hr .lbr Ibr 24hr Annual 24hrHospital - A -256.16 276.64 377 317.2 90.5 6.7 0.08 1.9 11.3 0.6 0.0 0.00 0.2Polkce Smn Posi Office- B -651 21 393 77 761 301.2 97 2 64 0 07 1.8 122 0 6 0.0 0 00 Q.1Mosque / Temple / Market - C -695.99 305.55 760 293.7 95.9 5.9 0.07 1.7 12.0 0.6 0.0 0.00 0.1School - D -921.13 27614 962 286 7 97.9 6 5 0 07 18 12 2 06 00 0 00 0 1St Francois Xavier RC Church - E -817.51 95.86 823 276.7 96.5 6.3 0.07 1.8 12.1 0.6 0.0 0.00 0.1Health Centre -F -984 23 -135 87 994 262 1 84 5 6 9 0 08 1.9 10.6 o 0.0 0 000 0.2Tenmple \iIkilge H-ill G 1113 4 113 -lb I I I 7 9ht 3 7 l 7 12' 1 .h ' i11. 1 11Communit) Cenire-H -1137.7 -284 19 1173 256'0 747 ( 9 u08 2U 9.3 0t d 0 U 3 0.00School - I -869.1 -302.09 920 250.8 54.0 6.6 0.09 1.9 6.8 0.3 t.1) 11"'i i2Mosque- J -1082 7 -53712 1209 243 6 521 56 009 l 6 5 0 3 00 u00 d 1Temple- K -894.46 -822.2 1215 227.4 53.3 5.5 0.08 1.5 6.7 0.3 0.0 0.00 0.1Cenictern - L -691.56 -984 82 1203 21 1 52 7 55 006 I 6 o6 03 7) u 00 U ITemple/VillageHall -M -820.42 -1152.7 1415 215.4 48.9 5.8 0.05 1.6 6.1 0.3 0.0 0.00 0.1Ma -N -721.97 -1254 1447 2799 52 1 5 3 o 05. 1 5 65 0.3S (I] 0 00- I

IAm., /2.1di 2fl05-ls: Sel L~calmos - Pige12.

Pollutant Concentration Qig/m 3) - CTSAV Crop Season

Relathe Location S02 NONX Co Dvine (x Ie-9) PNIIO)x (nA (j) Dial (m) Direct (deg) lhr 24hr Annual 24hr lhr lbr 24hr Annual Z4hrHospital -A -256.16 276.64 377 317.2 92.2 6.9 0.08 3.5 46.0 6.6 0.5 0.01 1.0Police Sm / Post Ofice - 8 -651.21 393 77 761 301 2 112.8 20 6 0.17 9.4 972 8 25.2 2.4 0 14 2 4Mosque / Temple / Market - C -695.99 305.55 760 293.7 112.9 21.7 0.20 9.8 1069.1 26.6 2.5 0.19 2.4School - D -921.13 276.14 962 286 7 11Z7 198 034 12 9 Q14.8 24 3 3 4 0 38 3 4St Francois Xavier RC Church - E -817.51 95.86 823 276.7 112.9 21.3 0.29 11.3 1021.0 26.3 2.9 0.30 2.8Health Cenne - F -984 23 -135 87 994 2b2 1 99 2 20.0 0 40 12 0 898.3 24 3 3.1 0 44 3 2Temples / Village Hall - G -1113.4 113.46 1119 275.8 109.6 18.0 0.44 13.3 819.5 21.8 3.6 0.51 3.8Cormmunity Cnrre - H -1137.7 .284 19 1173 256 0 89.7 20 4 0 49 13 0 919.2 24.8 3 4 0 56 3 8School -I -869.1 -302.09 920 250.8 72.6 23.6 0.37 11.6 1150.6 29.4 3.0 0.38 3.7Mosque - J -1082 7 -537 12 1209 243 6 71.0 23 0 0 46 13.6 1172 8 296 3.7 0 51 4.3Temple - K -894.46 -822.2 1215 227.4 66.7 17.4 0.32 12.9 814.5 22.2 3.5 0.33 4.2CemeLerb - L -691.56 -984 82 1203 215 1 66.2 17 5 0 22 11.9 817.9 22.3 3 2 0 22 3 4Temple / Village Hall - M -820.42 -1152.7 1415 215.4 61.8 17.2 0.23 13.4 779.3 21.5 3.6 0.25 3.5Market - N -721.97 -1254 1447 209 9 64 8 16 7 0 19 I 26 774 2 21 . 3 4 0 19 32

Pollutant Concentration (jig/m3) - CTSAV Intercrop Season

Relative Location S02 _ _ NOX CO Dio ine xI e-9 PM 10x (m) y (m. Dist (m) Direct (deg) Ihr 24hr Amunral 24hr lhr lbr 24br A.anual 24b rHospital - A -256.16 276.64 377 317.2 93.0 6.8 0.08 1.9 11.4 0.6 0.0 0.00 0.2Police Stn.1 Posi Oflice - B -651.21 393 77 761 301 2 260 6 25 4 149 6 3 18 2 2 2 0 2 r)01 0 4Mosque / Temple / Market - C -695.99 305.55 760 293.7 270.0 25.2 1.90 6.2 18.4 2.2 0.2 0.02 0.4School - D -921 13 27614 962 286 7 246 7 33 9 3 53 8.3 17 7 2 0 0 3 0 03 0 5St Francois Xavier RC Church - E -817.51 95.86 823 276.7 262.9 28.4 2.90 7.0 18.2 2.2 0.2 0.03 0.5Health Centre - F -984.23 -135 87 994 262 1 229.0 30 2 4 07 7 5 15 9 1 9 0 3 ' 04 0 51'emples/VillageHall -G -1113.4 113.46 1119 275.8 232.4 33 5 4.61 8.2 17.1 1.9 0.3 0.04 0.6Communiiv Centre- H -11377 -284 19 1173 s5o.0 211 2 33 1 5 06 8 2 14 4 1 ' U 3 0u5 ')6School - I -869.1 -302.09 920 250.8 234.8 30.0 3.61 7.4 13.4 2.1 0.3 0.03 0.5NMaque -J -1082 7 -537 12 1209 243 6 229 9 33 b 4 57 8 2 13.1 20 ° ) 3 0 14 0 6Temp!e - K -894.46 -822.2 1215 227.4 186.6 32.4 3.00 7.9 11.6 1.6 0.3 0.03 0.6Cemcrer-L -L 91 56 -9Y4 F2 1203 215 1 186 9 29 1 91 72 11 5 1 6 3 0 02 0 4Temple/Village Hall-M -820.42 -1152.7 1415 215.4 174.9 32.i 2.15 7.9 10.8 1.5 0.3 0.02 0.4Market -N -721 (7 -1254 1447 2u99 178S5 294 166 72 112 I 5 031 0302 04

Dw Ia 12.J,,ti 2005.rls. .Sel L-w i s - /',,gC

Maximum Concentrations - Baseline Crop Season Maximum Concentrations - Baseline Intercrop Season

| Max. Cone. (jig/m 3 ) I (m) y (m) Max. Cone. (pg/mr3 ) x (m) Y (m)S02- lhr 120.77 0 2000 S02- lhr 117.04 0 2000S02 - 24hr 21.09 -4924 868 S02 - 24hr 20.52 -4924 868S02 - Annual 0.26 -1000 0 S02 - Annual 0.17 -4924 868PM10 - 24hr 25.23 -1000 0 PM1O - 24hr 0.28 -4924 868Dioxine - Ihr (x I e-9) 31.99 -470 -171 Dioxine - lhr (x I e-9) 0.72 0 2000Dioxine - 24hr (x I e-9) 7.36 -1477 -260 Dioxine - 24hr (x I e-9) 0.13 -4924 868Dioxine - Annual (x le-9) 1.06 -1000 0 Dioxine - Annual (x le-9) 0.001 -4924 868NOX - 24hr 9.61 -4229 1539 NOX - 24hr 5.77 -4924 868CO- lhr 180.34 -470 -171 Co- Ihr 14.65 0 2000

Maximum Concentrations - CTSAV Crop Season Maximum Concentrations - CTSAV Intercrop Season

-- Max. Conc. (pig/m3) f x (m) y (mH) _Max. Cone. (uig/m 3) x (m)) 3Q()S02 - lhr 128.73 0 2000 S02 - lhr 242.43 -940 -342S02 - 24hr 22.59 -4924 868 S02 - 24hr 52.51 -4229 1539S02 - Annual 0.62 -1879 -684 S02 - Annual 6.21 -1879 -684PM10 - 24hr 4.94 -1879 -684 PM1O - 24hr 0.70 -1410 -513Dioxine - I hr (x I e-9) 31.30 -940 -342 Dioxine - I hr (x e-9) 2.13 -940 -342Dioxine - 24hr (x le-9) 5.33 -4229 1539 Dioxine - 24hr (x le-9) 0.44 -4229 1539Dioxine - Annual (x I e-9) 0.74 -1879 -684 Dioxine - Annual (x I e-9) 0.06 -1879 -684NOX - 24hr 22.00 -4229 1539 NOX - 24hr 13.26 -4229 1539CO- lhr 1222.99 -940 -342 CO- Ihr 18.85 0 2000

Data 12 JlYv 2005.xis: Max. Cui,e. - Page I12-.

Compagnie Thermique de SavannahOperation of a dual coal/bagasse-rired Power Plant


APPENDIX C - Coal Characteristics

, Zs %9 Dail<9 W 'i i , t 9N iUc il 3 M 4 VS.&l V3S. An 9

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_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

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APPENDIX D - Estimates of Cane Cultivation

Estimates of cane cultivation,harvest and yelids of SUDS factory areas for year 2007 and beyondl!!lNOTE The above estimates have been obtained from tne associated growing companes of SUDS from the factory areas of REE-MTMD-SAV -BRITANNIA & R.SelleArea under Area |normal I annual |mechanicall ts/trip I manual 15-20ts ts/tnp |6-7sts othercane. harvested yeildiHa Crop harvest med, harvest harvest tipping wholecanes slinged info?

Savannah SE 2525 2370 95 225150 180000 15-22 45150 45150 15-18 0MTMO 1928 1744 89 155500 77750 20 77750 77750 23 0Cie de Beau-Vallon 2374 2122 89 189000 136000 25 53000 53000 20 0Bntannia (MTMD) 640 575 88 50600 10000 19 40600 40600 15 0Benares (MTMD) 575 515 95 48925 35000 19 13925 13925 15 0Brit (SIT LH) 764 715 70 50050 0 50050 50050 15 0MTMD (SIT LH) 838 756 85 64500 10000 20 54500 54500 23 0R.Belle estate 1958 1808 72 130000 13000 15 117000 54000 12 63000*SmalItplanters fromSav factory area 6 875 73.5 49612.5 0 49612.5 0 49612.5MTMD factory area - 400 66.5 26600 0 26600 0 26600REE factory area

1050 61.5 64575 0 64575 0 64575R.Belle factory area 1050 60 63000 0 63000 0 63000Britannia factory area - 450 60 27000 t 27000 0f 27000SIT planters (brit & MTMD) 400 62 24800 0 24800 0 248001 ,169,313 46175t 707562.5 38897 31858TOTAL CANE SUPPLY TO FACTORY (Crop)

1,169,313

NOTE: In accordance with the PPA agreement to be signed with the CEB. Savannah mitl will Guarantee a cane supply of 1,200,000 tons yearly in orderto satisfy the Bagasse supply to the power plant. Consequently some canes will be diverted from the USA mill to Savannah mitl as requimed to satisfy this crtienia.BAGASSE TO POWER PLANT

ALL the bagasse produces from the canes entering the savannah cane yard (minimum 1,00.000 ts) willi be supplied to the power ptant.The proposal has been based on an AVERAGE fibre content of 15% and a bagasse humidity of 50%.This will give an ANNUAL supply of 360,000 ts of bagasse to the power plant.

Savannah crushing capacity - crop

Have been assumed the following for the PPA calculations

annual crop 1200000tdays crushing 150 (25 wks 6 dys w ik)ave crushing per day 8000 tave hrs crush per day 23 have crush capacity 350 IUhBagasse production 2400 t



APPENDIX E - Water Resources Analysis

SOCIETE USINIERE DU SUD

WATER RESOURCES AND UTILISATIONAT SAVANNAH

February 2004

S.I.G.M.A.- Ove Arup & PartnersConsulting Engineers

19 Church StreetPort LouisMauritius

SOCIETE USINIERE DU SUD

Water Resources and Utilisationat Savannah

Table of Contents

I INTRODUCTION

12 WATER RIGHTS

12.1 GENERAL

I2.2 RIVER DU POSTE

I2.3 RIVER TABAC AND RuISSEAU VINAY

22.4 RIVER ST. AMAND

22.5 SUMMARY

33 WATER UTILISATION

43.1 DESCRIPTION OF THE SYSTEM

43.2 MEASURED FLOW DATA

43.2.1 General

43.2.2 Summary of Flow Data 53.3 PRESENT WATER REQUIREMENTS AND UTILISATION 83.3.1 Irrigation Water 83.3.2 Factory Water

93.3.3 Typical Annual Water Utilisation 103.3.4 Combined Water Requirements

--- 103.4 WATER UTILISATION WITH POWER PLANT -I---- 113.4.1 Process Water Requirements 113.4.2 Demand Satisfaction 114 RECOMMENDATIONS

14

SOCIETt USINIERE DU SUD

Water Resources and Utilisationat Savannah

1 IntroductionThe Central Electricity Board (CEB) has launched a tender for a 30 + 30MW powerplant in December 2003. The Societe Usiniere du Sud has decided to respond to thistender and is therefore preparing an offer comprising the construction and operationof a steam power plant at Savannah.

The Societe Usiniere du Sud has appointed S.I.G.M.A. - Ove Arup & Partners to carryout an assessment of the available water resources and current water utilisation atSavannah to determine how the water requirements of their prospective power plantwill impact the current water utilisation. This is detailed in the present report.

2 Water Rights

2.1 GeneralThe Societe Usiniere du Sud comprises four sugar estates, namely the Savannah SugarEstate, the Britannia Sugar Estate, the Riche en Eau Sugar Estate and the Union SugarEstate, but since the prospective power plant is to be located at Savannah, it is mostlythe water rights of Savannah S.E. that have been reviewed. Those water rights, onRiver du Poste, River Tabac, Ruisseau Vinay and River St. Amand, are detailedhereunder.

It should be noted however that Britannia S.E. is also entitled to water shares on Riverdu Poste and River St. Amand, and therefore those water rights have also beenincluded in the review.

2.2 River du PosteThe various water rights granted to Savannah S.E. and Britannia S.E. on River duPoste are listed below.

a) Britannia S.E. has been allowed to take 9/50 of the flow of River du Poste at adam located at La Flora as defined in the Supreme Court Record No. 1979, dated17 May 1939.

b) Savannah S.E. has been granted 1/3 of the waters of the river at Joli Bois by"Arrete du Directoire" dated "17 Niv6se de l'an IV" (7 January 1796) but hasstopped the abstraction of water at this location. This share of water is allowed toincrease the river flows and is actually tapped further downstream as part ofanother water right.

c) The Supreme Court Record No. 1919, dated 17 May 1939 has allowed SavannahS.E. to take 274/284 of the flow of River du Poste at the Joli Bois Dam, a shortdistance downstream of the point mentioned in (a) above. This will comprise alsothe water right mentioned in (a) above. The remaining 10/284 is left in the riverfor public needs.

d) Further downstream, at the so called Abatis Dam, the Savannah S.E. has beengranted another 11/12 of River du Poste flows at that location by the SupremeCourt Record No. 23309 of the 29 June 1886. The estate used to divert water atthis point to Bassin Tronche via an open channel, but is presently making use of apipeline that has replaced the open channel.

e) The offtake works at the Abatis Dam do not enable Savannaah S.E. to abstract itsfull share of water as described in (c) above. The remainder is abstracted furtherdownstream at the location known as La Sourdine by means of a pumping station.

2.3 River Tabac and Ruisseau VinaySavannah S.E. has been granted the right to "4 inches of water" by the Land Court onthe 23 February 1858, which was then replaced by the authorisation to install a200mm pipe following Supreme Court Record No. 28070.Savannah S.E. makes use of this water right via two pumping stations. The first one islocated downstream of Bassin Canon while the second is located further downstreamat Bassin Zaza.

Following Supreme Court Record No. 1817, dated 12 August 1937, Savannah wasauthorised to construct a reservoir on Ruisseau Vinay and to supply this reservoir withwater diverted from River Tabac via a canal originating from Bassin Canon. SavannahS.E. was then given the right to use 65% of the combined flows from River Tabac andRuisseau Vinay.

2.4 River St. AmandThe flows of River St. Amand have been divided equally between Savannah S.E. andBritannia S.E further to "Arretes du Directoire" dated "17 Niv6se An IV' (7 January1796) and "22 Frimaire An Vl" (12 December 1797).

Britannia S.E. abstracts its share of the river flows via the canal de Launay whichstarts on the right bank of the river, upstream of its confluence with Ruisseau BatiBontemps.

Since 1999, Savannah S.E. has also started to abstract its share of water by means of apumping station located at the de Launay dam and conveys water via a 200mmpipeline to Bassin Tronche.

2.5 SummaryThe water rights detailed in the preceding sections have been summarised in Table2.5.1 below, and illustrated in Figure 2.5.1 hereafter.

Source Authority

Share of FlowI_ --River Flow (cusec)River du Poste

Arrete du Directoire 274/284 8.3(Joli Bois Dam) (17 Nivose An IV)S.C.R. No. 1919(Judg. 17.5.1939)

River du Poste S.C.R. No.23309

11/12 5.3(Abatis Dam) (Judg. 29.6.1886)

v River du Poste

2.27| (La Sourdine Pump Stn.)

> River Tabac - Ruisseau Vinay L.C.O. (23.2.1858) 65%Bassin Canon Pump Stn. S.C.R. No. 28070

1.0Bassin Zaza Pump Stn. S.C.R. No. 1817 2.13Ruisseau Vinay (Bassin Camarons) (Judg. 12.8.1837) 4.0

River St. Amand Arr&e du Directoire 50% -(17 Niv6se An IV)

River du Poste S.C.R. No. 1979 9/50 1.3

v (La Flora) (Judg. 17.5.1939)

a River St. Amand Arrete du Directoire 50%(22 Frimaire An VI)

Table 2.5.1: Summary of water rights

It is worth mentioning that the flow values stated in the above table have beenreproduced from copies of the Notification of Water Right Schedules given inAppendix I hereto. They should be considered as being indicative only since theimplementation of the La Flora Dam is believed to have significantly reduced theriver flows downstream. A better indication of the water available will be obtainedfrom the flow data measured by the estate (see next section).

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SOCET3USI1ERE DU SU

4 -Ri,. do Pom c o, ~ WR mc.2 sav.o. S.R

Water Rasire. SWd Uuta.eucA Savamak

S - Ok. Taboo (Buaj Clum) 65% (V"q .t I asmc) sovmanh S.0.

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6 -RN* Tao (Ba tic Zen): h5%(pu* maL 2i aic) swa,.* SR.

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Water Resources and Utilisation at Savannah Page 4

3 Water Utilisation

3.1 Description of the SystemThe water available to the estates is used to satisfy their factory and irrigation waterrequirements. The system currently in place is briefly described below, and depictedschematically in Figure 3. 1.1 hereafter.

The water abstracted at the Joli Bois Dam on River du Poste is used both for thefactory and irrigation requirements. The actual apportionmenit of water depends on thevolumes of water actually available and on the priorities defined by the estate.The water abstracted at the Abatis Dam further downstream on River du Poste isconveyed via a pipeline to Bassin Tronche and is thereafter used for irrigation. BassinTronche also receives the water pumped from River St. Amand at the de LaunayDam.

The last tapping point on River du Poste is located at La Sourdine where the water ispumped for irrigation.

Water from River Tabac is first abstracted at the Bassin Canon pumping station and ispumped through a 200mm pipeline to meet the water requirements of the factory.Further downstream, at Bassin Zaza, another pumping station is being used to transferwater to Bassin Camarons where it joins the waters of Ruisseau Vinay, before beingultimately pumped into the irrigation system. There was another abstraction poinlt atBassin Canon which used to convey water by an open channel to Bassin Camarons,but this diversion is not in operation anymore.

Regarding the water right of Britannia S.E. on River du Poste (at La Flora), it shouldbe noted that no water is presently being abstracted by the estate. Their share of wateris left to the river.

3.2 Measured Flow Data

3.2.1 GeneralSavannah S.E. regularly records their water abstraction on the various offtake worksin operation on the estate. Those flow records have been obtained and examined in anattempt to quantify the actual water available to the estate from their water rights onthe neighbouring rivers.

The following points should be mentioned about the data available:* Data is generally available over a common period of 8 years from July 1995 toDecember 2003 and this is adequate to identify general trends.* The data obtained is a weekly flow record that is not suitable for carrying out adetailed statistical analysis of the flows.

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* The canal flows are partial data series and there are "gaps" in the data. Someof those gaps are due to the closing down of one of the water lines for repairs.* The data for La Sourdine pumping station and for Bassin Camarons pumpingstation are not available over the same period as the other stations. Averagevalues given by the estate will be adopted.

3.2.2 Summary of Flow DataThe flow data obtained have been combined and the average, minimum and maximumobserved flows are summarised in the tables below. Detailed flows values for eachmeasured location is given in Appendix II hereto.

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 - - - - - - - - 6.43 6.00 6.63 6.821995-1996 7.29 4.90 5.76 5.18 4.88 3.44 1.03 4.23 8.30 8.58 7.27 7.511996-1997 8.28 7.40 8.50 8.95 8.55 9.10 8.25 7.68 8.63 8.36 8.38 7.681997-1998 8.05 7.74 8.28 6.50 8.58 7.48 4.40 7.70 8.63 8.36 8.38 7.301998-1999 8.23 5.50 4.24 6.83 8.05 7.82 7.23 5.85 7.93 9.40 9.48 8.081999-2000 5.98 7.56 6.98 6.60 8.00 6.60 7.80 8.85 9.25 8.56 10.30 11.05

2000-2001 10.45 9.52 9.86 8.64 8.65 6.51 8.35 5.54 4.60 7.80 6.63 10.412001-2002 10.71 8.09 6.66 8.40 8.40 8.70 8.40 7.43 4.80 7.60 9.38 10.502002-2003 10.23 9.62 8.70 10.30 9.73 6.75 4.50 4.50 4.50 4.50 8.50 10.842003-2004 10.89 8.57 10.71 - - - - - -

Table 3.2.2.1: Average observed flows (cusec)

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 - - - - - - - - 3.40 4.33 5.89 5.801995-1996 6.11 3.70 5.60 4.90 4.00 0.80 0.80 1.70 8.30 8.10 5.80 6.751996-1997 7.30 6.70 7.40 8.30 8.30 8.30 4.40 4.40 8.50 8.10 8.30 6.601997-1998 8.00 7.30 8.00 4.40 8.50 4.40 4.40 4.40 8.50 8.10 8.30 6.601998-1999 6.50 5.00 4.10 4.10 7.30 6.60 6.50 5.60 6.50 9.20 9.40 7.101999-2000 5.10 5.70 4.50 4.50 8.00 4.50 4.50 8.10 8.10 8.10 10.20 10.302000-2001 9.80 8.70 6.90 6.35 8.65 6.05 8.35 4.60 4.60 7.30 5.80 9.602001-2002 8.95 7.85 - 8.40 8.30 8.70 8.30 4.80 4.80 4.90 7.90 9.602002-2003 8.35 9.10 5.80 10.30 8.00 4.50 4.50 4.50 4.50 4.50 8.50 9.502003-2004 9.80 7.75 8.55 - _ - - - - - - -

Table 3.2.2.2: Minimum observed flows (cusec)

Nov Dee Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 - - - - - - - - 7.50 7.50 7.95 7.701995-1996 8.74 5.80 5.90 5.50 5.20 5.20 1.70 5.60 8.30 8.70 8.60 8.901996-1997 9.60 7.70 9.80 9.80 8.70 9.30 9.70 8.80 8.80 8.60 8.50 8.101997-1998 8.10 8.10 8.40 8.60 8.60 8.40 4.40 8.801 8.80 8.60 8.50 8.001998-1999 9.40 5.80 4.30 9.30 8.90 8.70 7.80 6.50 9.00 9.50 9.50 9.401999-2000 7.00 9.10 9.00 9.40 8.00 8.00 9.10 9.10 10.40 10.40 10.40 11.302000-2001 10.90 11.00 11.30 9.85 8.65 8.35 8.35 6.90 4.60 8.10 7.30 11.152001-2002 12.35 8.65 8.40 8.40 8.70 8.70 8.70 8.30 4.80 9.40 10.80 11.752002-2003 11.95 10.30 10.30 10.30 10.30 10.301 4.50 4.50 4.50 4.50 8.50 11.802003-2004 11.75 9.35 11.25 - - - - - - .

Table 3.2.2.3: Maximum observed flows (cusec)

Since the available data do not allow a detailed statistical analysis to be carried out, itis proposed to consider two cases, which are namely the minimum and maximumcombined flows, on a monthly basis. Tables 3.2.2.4 hereunder, together with thecharts of Figures 3.2.2.1, 3.2.2.2 and 3.2.2.3, indicate the observed variation inminimum and maximum flows.

Month Minimum flows (cusec) Maximum flows (cusec)November 5.10

12.35December 3.70

11.00January 4.10

11.30February 4.10

10.30March 4.00

10.30April 0.80

10.30May 0.80

9.70June 1.70

9.10July 3.40

10.40August 4.33

10.40September 5.80

10.80October 5.80

11.80

Table 3.2.2.4: Variation in observed flows

The combined flow values in this section do not account for the flows recorded at LaSourdine and Bassins Camarons pumping stations. The following average values,given by the estate, have been adopted and will be added to the flow values in theabove table:

* La Sourdine pumping stn.: 1.81cusec (185m 3/hr)* Bassin Camarons pumping stn.: 1.23cusec (125m3 /hr)

Table 3.2.2.4 should therefore be updated to read as follows:

Month Minimum flows (cusec) Maximum flows (cusec)November 8.14

15.39December 6.74

14.04January 7.14

14.34February 7.14

13.34March 7.04

13.34April 3.84

13.34May 3.84

12.74June 4.74

12.14July 6.44

13.44August 7.37

13.44September 8.84

13.84October 8.84

14.84

Table 3.2.2.4 (updated): Variation in observed flows

Flow (cusec)

Flow (cusec)ON J ON ON N o N KS

rC 00a 0 N -NC K

994-1995

1994-1995

1995-19)96 L1995-1996

isw6X9s7 8 1 3 -1996-1097 - 3

997-1998- ] 1997-1993 -0

199S-1999

1998-1999 2

1999-2000

19- t l99-2000iW

2000-2001

-2000-2001

2001-2002

2001-2002

2002-2003

2003-204 -2003-2004

Flow (curec) 1 Flow (cusec)

rN 1 8 ON 8N 8N 8 8 8S

A ON ON 8N S

Si994-1995 1994-1995

1995-1996 1995-1996

1996-1997

1996-1979

1997-1990

1997-1990

^9981999 -- 199 1 99 9 ;999

ZC71999-2000 -

1999-2000

2000-201)i

2000-2001 -

0 0

2001-2002 1

C

2002-2003

2002-2003

2003-2004 - -

2003-2004

a t

JO

Flow (cusec)

Flow (cusec)2 S S S S 8 S 8 S1994-1995{

1994-i 99511 - -1995-1996

1995-1996

1996-1997 --

1996-19971997-1998

1997-1998

1998-1999

1998-1999

1999-2000 -

1999-2000

2000-200 1 -

2000-2001

2001-2002

2001 -2002c

2002-2003

2002-2003

2003-2004-

2003-2004

0M0

Flow (cusec)

Flow (cusec)

1994-1995

1994-1995

1995-1996

1995-1996

996-1997 * * 1996-l997 -4

1997-1999 -

1997-1998

1 998-I 999

I J g 4 1998-Il999

1999-2000 -

1999-2000

2000-2001

2000-2001

2001-2002

2001-2002

2002-2003 -

2002-2003

2003-2004

2003-2004

0 ~ ~~ @W tU

Flow (cusec)

Flow (cusec)o c5 8: 8i 8. 8 8 8 8 8 8S F5 5 81994-1995

I994-1995

1995-1996

1995-1996

1996-1997

1996-1997

1997-1998

1997-1998

1996-1999 -

1998-1999

1999-2000

1 999-2000

2000-2001

2000-2001

2001-2002

2001-2002t 2002-2003

-002-2003

2003-2004 -2003-2004

Fs3

B Flow (cusec)

Flow (cusec)

1994-1995

1994-19951995-1996 8 8 t 8 1995-1996

1996-1997

1996-1997

1997-1999

179

1998-1999 -

0 1998-1999 00

1999-2000 <9- -

l999-2000 -

-20009-2001 -464 1

0

2001-2002

20O1-2002 -

2002-2003

02 -

2003-2004 _ 2003-2004

3.3 Present Water Requirements and Utilisation3.3.1 Irrigation WaterIrrigation water consumption data has been supplied by Savannah S.E. for 3 typicalyears and is reproduced hereunder.

Irrigation Scheme Area Water Consumption Water Source(ha) (cusec)LB & SV Elec. B. Camaron 86 1.33 Bassin Zaza(sprinkler)

Bassin CamaronLB & SV Diesel 57 1.33 Bassin Camaron(sprinkler)

Joli BoisSV Elec. La Digue 99 1.33 Bassin Camaron(sprinkler)

Bassin ZazaBassin CanonJoli BoisLB La Sourdine

56 2.26 La Sourdine(Big gun)

SH Gravitational 173 5.42 Riche Bois(Big gun)

TOTAL 471 11.67

- -Table 3.3.1.1: Irrigation water consumption for 1980

Irrigation Scheme Area Water Consumption Water Source(ha) (cusec)LSBV Fixed Network

159 2.94 Joli Bois(Big gun)

LSBV Drip irrigation 74 2.01 B. Camaron

Bassin ZazaBassin CanonLB La Sourdine

56 2.26 La Sourdine(Big gun)

SH Center Pivot 400m 50 0.90 Riche BoisL'AbatisSH Center Pivot 600m 113 2.06 Riche BoisL'AbatisSH Drip irrigation

44 0.98 L'AbatisSH Travelling gun 44 0.88 Riche BoisTOTAL

540 12.03 --. - -

Table 3.3.1.2: Irrigation water consumption for 1996

Irrigation Scheme Area Water Consumption Water Source(ha) (cusec)LSBV Big gun fixed network 174 4.02 Joli BoisLB Aldar Big gun fixed network 43 1.47 Bassin ZazaLBSV Drip irrigation 83 2.01 Bassin Camaron

Bassin ZazaLB La Sourdine 48 2.26 La Sourdine(Big gun)

SH Center Pivot 400m 50 0.90 Riche BoisL'AbatisSt. AmandSH Center Pivot 600m 113 2.06 Riche BoisL'AbatisSt. AmandSH Center Pivot 38Dm 45 0.88 Riche BoisL'AbatisSt. AmandSH Drip irrigation

34 0.98 L'AbatisSt. AmandSH Travelling gun 44 0.88 Riche BoisTOTAL

634 15.46

Table 3.3.1.3: Irrigation water consumption for 2003

The data obtained for 1980 will not be considered since there is no flow recordavailable for this period, but the other 2 years can be considered as being the irrigationwater requirements before and after 1999. During that year, the implementation of theSt. Amand pumping station and the replacement of the earthen canal from BassinZaza by a pipeline improved the overall satisfaction of the water requirements on theestate.

3.3.2 Factory WaterThe factory water requirements have been given to be 2.5cusec (-253m3 /hr). Thefactory uses water year round from the Bassin Canon pumping station (1 cusec) with apeak being reached during the crop season between June and November. During thistime, the remaining factory water requirements are being met from Joli Bois.The factory water requirements will be reduced to 1 .5cusec (-1 53m 3 /hr) following theimplementation of a cooling tower, and thus make available I cusec for other uses.

3.3.3 Typical Annual Water UtilisationThe typical annual water utilisation on the estate from each of the abstraction pointsconsidered has been tabulated hereafter in Table 3.3.3.1. This table shows thatirrigation water is required year round and also that some of the water available fromJoli Bois is being allocated to factory use during the crop season, at the expense ofirrigation.

Joli Bois Abatis La Sourdine Bassin Bassin Zaza Bassin St. AmandDam Dam Pump Canon Pump Pump Camaron Pump Pump

San Irrigation V V V / / /

Factory .Feb Irrigation

V $ V

V V VFactory

Mar Irrigation / V V/ v

V

........ ~~~~~~~~.. ... .... . .. ...... ..... ... . . ....... .. ...... ... .. ............ ....... . ...... ..... ....... . ........ .......... .....

.... ... .... . ........ ............... .............. ................

Factory

VApr Irrigation I/ v -

V V/Factory

IMay Irrigation V V

V /

- .. ..iato .. .... ... .. . .. ..- . ... . ....... .. ... ... ...... . ..

. .. .... .. .....Factory

VJun Irrigation V V V V V V

Factory

.Jul Irrigation

V V V

V V VFactory V

VAug Irrigation V V V V V V

Factory V VSep Irrigation . V V.

V. VFactory VV

Oct Irrigation V V

V V

t et Irrigatio.... . . ... .

. . . . .Factory V

VNov Irrigation V/ V/ V V

V,Factory V

Dec Irrigation V I "

V/ VFactory

V

Table 3.3.3.1: Typical annual water utilisation at Savannah

3.3.4 Combined Water RequirementsThe combined water requirements of Savannah S.E., comprising irrigation andfactory, can thus be taken to be presently of the order of 1 8cusec (1 5.5cusec irrigationand 2.5cusec factory).

For the purposes of this study, the combined water requirements prior to theimplementation. of the St. Amand pumping station and new pipeline from Bassin Zazapumping station will also be taken into consideration and a value of 14.5cusec willthus be used (12.Ocusec irrigation and 2.5cusec factory).

3.4 Water Utilisation with Power Plant

3.4.1 Process Water RequirementsThe process water requirements of the prospective power plant have been given to be2.7cusec (-275m3 /hr). However, lOOm /hr (-35%) of this volume can be returned tothe irrigation system after suitable treatment of the power plant site.The demand on the existing system, due to the power plant, will therefore be 1.7cusec(-175m3/hr).

3.4.2 Demand SatisfactionWith reference to Table 3.2.2.4, it is clear that even during maximum flow conditionsthe Savannah S.E. water requirements are not fully met. So that if priority is given tothe estate water requirements, there will definitely not be sufficient water to supplythe power plant.

The level of water demand satisfaction has been evaluated for each month asdescribed in the following examples.

e.g. 1: Min. satisfaction in March 1997

Minimum observed flow: 8.30cusecLa Sourdine + Bassin Camarons: 3.04cusecEstate requirements (before 1999): 14.5cusec

Percentage satisfaction = (8.30 + 3.04) / 14.5= 78%

e.g. 2: Max. satisfaction in November 2001

Maximum observed flow: 12.35cusecLa Sourdine + Bassin Camarons: 3.04cusecEstate requirements (after 1999): 18.00cusec

.. Percentage satisfaction= (12.35 + 3.04) / 18.0= 86%

The level of water demand satisfaction for the estate has been computed as indicatedabove, and lies in the range of 26%, in minimum flow conditions, to 89%, inmaximum flow conditions as indicated in the tables given thereafter.

Nov Dec Jan Feb Mar Apr May Jun Jul Aug| Sep Oct1994-1995 44% 51% 62% 61%1995-1996 63% 46% 60% 55% 49% 26% 26% 33% 78% 77% 61% 68%1996-1997 71% 67% 72% 78% 78% 78% 51% 51% 80% 77% 78% 66%1997-1998 76% 71% 76% 51% 80% 51% 51% 51% 80% 77% 78% 66%1998-1999 66% 55% 49% 49% 71% 66% 66% 60% 66% 84% 86% 70%1999-2000 45% 49% 42% 42% 61% 42% 42% 62% 62% 62% 74% 74%2000-2001 71% 65% 55% 52% 65% 51% 63% 42% 42% 57% 49% 70%2001-2002 67% 61% 64% 63% 65% 63% 44% 44% 44% 61% 70%2002-2003 63% 67% 49% 74%1 61% 42% 42% 42% 42% 42% 64% 70%2003-2004 71% 60% 64%° =

Table 3.4.2.1: Level of satisfaction for estate requirements (min. conditions)

Nov Dec| Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 73% 73% 76% 74%1995-1996 81% 61% 62% 59% 57% 57% 33% 60% 78% 81% 80% 82%1996-1997 87% 74% 89% 89% 81% 85% 88% 82% 82% 80% 80% 77%1997-1998 77% 77% 79% 80% 80% 79% 51% 82% 82% 80% 80% 76%1998-1999 86% 61% 51% 85% 82% 81% 75% 66% 83% 86% 86% 86%1999-2000 56% 67% 67% 69% 61% 61% 67% 67% 75% 75% 75% 80%2000-2001 77% 78% 80% 72% 65% 63% 63% 55% 42% 62% 57% 79%2001-2002 86% 65% 64% 64% 65% 65% 65% 63% 44% 69% 77% 82%2002-2003 83% 74% 74% 74% 74% 74% 42% 42% 42% 42% 64% 82%2003-2004 82%° 69% 79% -

Table 3.4.2.2: Level of satisfaction for estate requirements (max. conditions)The same exercise has been repeated, but this time by giving priority to the waterrequirements of the prospective power plant, and by taking into account the reductionin the factory water requirements from 2.5 to 1.5cusec. The level of water demandsatisfaction has again been evaluated for each month as described in the followingexamples.

e.g. 3: Min. satisfaction in March 1997

Minimum observed flow: 8.30cusecLa Sourdine + Bassin Camarons: 3.04cusecReduced estate requirements (before 1999): 13.5cusecPower plant requirements: I .70cusec

. . Percentage satisfaction = (8.30 + 3.04 - 1.70) / 13.5= 71%

e.g. 4: Max. satisfaction in November 2001

Maximum observed flow: 12.35cusecLa Sourdine + Bassin Camarons: 3.04cusecReduced estate requirements (after 1999): 17.00cusecPower plant requirements: 1.70cusec

.Percentage satisfaction (12.35 + 3.04 - 1.70) / 17.081%

The level of water demand satisfaction for the estate now lies in the range of 16%, inminimum flow conditions, to 83%, in maximum flow conditions as indicated in thetables below.

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 - 35% 42% 54% 53%1995-1996 55% 37% 51% 46% 40% 16% 16% 23% 71% 70% 53% 60%1996-1997 64% 60% 65% 71% 71% 71% 43% 43% 73% 70% 71% 59%1997-1998 69% 64% 69% 43% 73% 43% 43% 43% 73% 70% 71% 59%1998-1999 58% 47%1 40% 40% 64% 59% 58% 51% 58% 78% 80% 63%1999-2000 38% 41% 34% 34% 55% 34% 34% 56% 56% 56% 68% 68%2000-2001 66% 59% 48% 45% 59% 43% 57% 35% 35% 51% 42% 64%2001-2002 61% 54% 57% 57% 59% 57% 36% 36% 37% 54% 64%2002-2003 57% 61%, 42% 68% 55% 34% 34% 34% 34% 34% 58% 64%2003-2004 66% 53% 58%

_

Table 3.4.2.3: Level of satisfaction for estate requirements (min. conditions)

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995

65% 65% 69% 67%1995-1996 75% 53% 54% 51% 48% 48% 23% 51% 71% 74% 74% 76%1996-1997 81% 67% 83% 83% 74% 79% 82% 75% 75% 74% 73% 70%1997-1998 70% 70% 72% 74% 74% 72%° 43% 75% 75% 74% 73% 69%1998-1999 80% 53% 42% 79% 76% 74% 68% 58% 77% 80% 80% 80%1999-2000 49% 61% 61% 63% 55% 55% 61% 61% 69% 69% 69% 74%2000-2001 72% 73% 74% 66% 59% 57% 57% 48% 35% 56% 51% 73%2001-2002 81% 59% 57% 57% 59% 59% 59% 57% 36% 63% 71% 77%2002-2003 78% 68% 68% 68% 68% 68% 34% 34% 34% 34% 58% 77%2003-2004 77%1 63% 74% = = =

Table 3.4.2.4: Level of satisfaction for estate requirements (max. conditions)The above tables confirm discussions held with representatives of Savannah S.E.whereby the available water resources to the estate are presently not adequate to meetfully their water requirements, and this is believed to be a consequence of theimplementation of a dam at La Flora upstream of the estate's water rights.

4 RecommendationsAfter investigating the water resources presently available to Savannah S.E., it hasbeen found in the present situation that it is not possible to satisfy the estate's waterrequirements as well as those of the prospective power plant. It has also been found,with the given flow data, that giving priority to the power plant's water requirementswill significantly lower the level of satisfaction of the estate's water requirements.

Now, Britannia S.E. has a water right on River du Poste at La Flora which is not beingutilised, and it is therefore recommended that an appropriate scheme is implementedto abstract the water to which they are entitled. It should be pointed out, however, thatit is difficult at this stage, in the absence of hydrologic data, to predict the volumes ofwater that will effectively be obtained. It is also probable that such an abstraction willhave an effect on Savannah's water rights at Joli Bois Dam downstream, butdepending on the drainage area between the two abstraction points (and hence therunoff into the river) and the water lost to the aquifer through the bed of the river, thiseffect might be minimal.

Another potential source of water to satisfy the power plant water requirements isunderground water. In this respect, it is recommended that an application be filed withthe Water Resources Unit which is the relevant institution to authorise groundwaterabstraction and also to sanction the volumes that can safely be pumped.

-0 -

Appendix I

Notification of Water Right Schedules

Appendix 11

Detailed Flow Data

Joli Bois Mean Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 4.03 4.14 3.88 4.131995-1996 2.90 3.52 4.50 4.20 4.18 4.17 4.03 4.20 4.08 3.70 3.731996-1997 3.65 3.68 4.12 4.20 3.93 3.90 3.90 4.37 4.23 3.96 3.98 3.601997-1998 3.65 3.34 3.88 4.20 4.18 3.85 4.40 4.23 3.96 3.98 3.601998-1999 3- 18 1.74 0.96 2.45 3.10 3.06 2.88 2.80 3.40 4.00 4.08 3.601999-2000 2.78 3.36 4.13 4.20 3.50 2.10 3.30 4.60 4.60 4.60 4.50 4.50

2000-2001 3.65 3.06 4,32 4.90 4.90 4.60 4.60 4.60 4.60 4.40 4.13 3.102001-2002 3.90 2.98 4.83 4.90 4.80 4.80 4.80 4.80 4.80 4.90 4.68 3.382002-2003 3.05 3.16 2.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.252003-2004 3.63 3.36 3.76

Joli Bois Min. Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Au Se Oct

1994-1995 .3.90 3.60 3.60 3.90

1995-1996 2.60 2.20 4.10 4.00 4.00 4.10 0.00 3.90 4.20 4.00 3.40 3.201996-1997 3.30 2.70 3.90 4.00 3.90 3.90 3.90 4.30 4.10 3.70 3.90 3.601997-1998 3.60 2.90 3.60 4.20 4.10 3.80 0.00 4.40 4.10 3.70 3.90 3.601998-1999 2.50 1.40 0.90 0.90 2.80 2.60 2.70 2.50 3.00 3.80 4.00 3.201999-2000 2.30 2.30 3.60 3.50 3.50 0.00 0.00 4.60 4.60 4.60 4.40 4.50

2000-2001 3.00 2.40 3.00 4.90 4.90 4.60 4.60 4.60 4.60 4.10 3.80 2.702001-2002 3.50 2.80 4.80 4.90 4.80 4.80 4.80 4.80 4.80 4.90 4.00 3.202002-2003 2.50 2.30 0.00 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 3.502003-2004 3.00 2.80 2.80

Joli Bois Max. Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 _ _

4.10 4.40 4.10 4.201995-1996 3.10 4.20 4.90 4.60 4.40 4.20 0.00 4.10 4.20 4.10 4.00 4.301996-1997 4.00 4.30 4.30 4.30 4.00 3.90 3.90 4.40 4.40 4.20 4.10 3.601997-1998 3.70 3.70 4.00 4.20 4.20 4.00 0.00 4.40 4.40 4.20 4.10 3.601998-1999 4.00 2.00, 1.00 3.90, 3.50 3.30 3.00, 3.10 3.60. 4.10 4.10, 4.001999-2000 3.60 4.10 4.50 4.90 3.50 3.50 4.60 4.60 4.60 4.60 4.60 4.50

2000-2001 4.10 4.20 4.90 4.90 4.90 4.60 4.60 4.60 4.60 4.60 4.30 4.002001-2002 4.20 3.20 4.90 4.90 4.80 4.80 4.80 4.80 4.80 4.90 4.90 3.502002-2003 3.70 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.502003-2004 4.00 4.00 4.00 _ _ _ _ _ _ _ - _ _

Bassin Tronche Mean Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Au Se F Oct

1994-1995 3.40 1.44 2.05 2.00 . P Y __r

1995-1996 3.67 3.40 3.40 2.37 2.581996-1997 2.43 2.84 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 2.701997-1998 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 2.701998-1999 3.05 1.76 1.28 2.63 2.95 2.76 2.35 2.30 3.03 3.40 3.40 2.481999-2000 1.20 2.40 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.502000-2001 3.50 3.50 2.96 1.25 0.00 0.00 0.00 0.00 0.00 3.40 2.50 3.652001-2002 2.63 1.52 3.50 3.50 3.60 3.90 3.60 2.63 0.00 2.70 3.6 3.102002-2003 2.68 2.98 3.50 3.50 3.50 1.50 0.00 0.00 0.00 0.00-4.00 3.752003-2004 3.38 1.70 3.30 . - - -

Bassin Tronche Min. Monthly Flow (cusec)Nov Dec Jan Feb Mar A r May Jun Jul Au Se Oct

1994-1995 1_ 3.40 0.73 1.09 0.90

1995-1996 2.91 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.40 3.40 1.20 2.231996-1997 1.80 1.80 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 2.001997-1998 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 2.001998-1999 2.00 1.60 1.20 1.20 2.50 2.00 1.80 2.00 2.50 3.40 3.40 1.601999-2000 0.80 1.30 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.502000-2001 3.50 3.50 2.00 0.00 0.00 0.00 0.00 0.00 0.00 3.00 2.00 3.502001-2002 1.50 1.00 3.50 3.50 3.50 3.90 3.50 0.00 0.00 0.00 2.00 2.902002-2003 2.10 2.10 3.50 3.50 3.50 0.00 0.00 0.00 0.00 0.00 4.00 3.002003-2004 3.00 0.00 2.50 =

Bassin Tronche Max. Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 T _ I-- -r- 3.40 3.40 3.35 2.80

1995-1996 4.94 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.40 3.40 3.40 3.401996-1997 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.401997-1998 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.40 3.401998-1999 3.40 1.80, 1.30 3.40 3.40, 3.40 2.80, 2.50 3.40, 3.40 3.40, 3.401999-2000 1.40 3.20 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.50 3.501 3.502000-2001 3.50 3.50 3.50 3.50 0.00 0.00 0.00 0.00 0.00 3.50 3.00 3.802001-2002 3.50 2.50 3.50 3.50 3.90 3.90 3.90 3.50 0.00 4.50 4.50 3.502002-2003 3.50 3.50 3.50 3.50 3.50 3.50 0.00 0.00 0.00 0.00 4.00 4.002003-2004 3.-50 3.00 3.50,

Bassin Canon Mean Monthly Flow (cusec)

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995

..1995-1996 0.55 1.26 0.98 0.93 0.94 0.78 0.701996-1997 0.30 0.60 0.30 0.35

1997-1998 - .1998-1999

.1999-20002000-2001 .2001-20022002-2003 . -2003-2004

.

Bassin Canon Min. Monthly Flow (cusec)

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 0.00 0.00 0.0O 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0o001995-1996 0.00 0.10 1.00 0.80 0.80 0.80 0.70 0.70 0.00 0.00 0.00 0.001996-1997 0.00 0.00 0.30 0.60 0.30 0.00 0.30 0.00 0.00 0.00 0.00 0.001997-1998 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001998-1999 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001999-2000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002000-2001 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002001-2002 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002002-2003 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002003-2004 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00-

Bassin Canon Max. Monthly Flow (cusec)

Nov Dec Jan Feb Mar Apr May Jun Jull Aug Sep| Oct1994-1995 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001995-1996 O.0O 1.00 1.70 1.20 1.00 1.00 0.80 0.70 0.00 0.00 0.00 0.001996-1997 0.00 0.00 0.30 0.60 0.30 0.00 0.40 0.00 0.00 0.00 0.00 0.001997-1998 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001998-1999 0.00 0.00, 0.00 0.00, 0.00 0.00 0.00, 0.00 0.00 0.00 0.00 0.001999-2000 0o.0 0.00 0.00 0.°l 0.00 0.00 0.00 0.0 0.00 0.00 0.00° 0.00

2000-2001 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002001-2002 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002002-2003 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002003-2004 0.00 0.00 0.00 0.00 .O 00 0.r-00 0.00 0.00 0.00 0.00 0.00 0.0011

Bassin Canon Mean Monthly Flow (cusec)(PumpD)

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 0.70 0.70 0.701995-1996 0.68 0.67 070 1.10 1.20 1.20 -1996-1997 1.20 1.20 1 20 1.I0 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.001997-1998 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.001998-1999 1.00 1.00 [.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00. 1.001999-2000 1.00 1.00 0.80 1.00 1.00 1.00 1.00 0.75 0.00 0.00 0.00 0.75

2000-2001 1.00 1.00 0.80 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.002001-2002 1.00 0.80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.50 1.002002-2003 0.75 0.60 0.40 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.502003-2004 0.50 0.00 0.00o

Bassin Canon Min. Monthly Flow (cusec)(pump)

I Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-1995 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.70 0.70 0.701995-1996 0.60 0.60 0.00 0.00 0.00 0.00 0.00 0.00 0.70 0.70 1.20 1.201996-1997 1.20 1.20 1.20 1.00 1.00 1.00 1.00 1.00 1.00 I.00 1.00 1.001997-1998 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.001998-1999 1.00 1.00 i.00 1.00 1.00 1.00 1.00 1.00 1.00, 1.00 1.00 1.001999-2000 1.00 1.00 0.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00

2000-2001 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.002001-2002 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 I.002002-2003 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 o.00 0.00o 0.002003-2004 0.00 0.00 0.00 0.00o 0.00 o.0o 0.00 0.00 00 0.00 0.00o o.00Bassin Canon Max. Monthly Flow (cusec)(Pumpn). Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.70 0.70 0.701995-1996 0.80 0.80 0.00 0.00 0.00 0.00 0.00 0.00 0.70 1.20 1.20 1.201996-1997 1.20 1.20 1.20 1.20 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.001997-1998 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.001998-1999 1.00 1.00 1.00 1.00 1.00, 1.00 1.00. 1.00 1.00- 1.00 1.00i 1.001999-2000 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 1.00o2000-2001 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.002001-2002 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 1.02002-2003 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.002003-2004 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00o 0.00 0.0

Bassin Zaza (Pump) Mean Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 .

-1995-1996 0.20 0.95 1.00 1.00 .

.1996-1997 1.00 1.00 1.00 1.00 1.00 1.00 1.50

- -1997-19981998-1999 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.001999-2000 1.00 1.00 0.20 0.00 0.00 0.00 0.00 0.00 1.15 0.46 2.30 2.30

2000-2001 2.30 1.96 1.78 1.15 2.30 0.46 2.30 0.58 0.00 0.00 0.00 2.302001-2002 2.10 1.34 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.58 2.302002-2003 2.30 2.30 2.30 2.30 1.73 0.46 0.00 0.00 0.00 0.00 0.00 1.982003-2004 2.30 2.06 2.20 _ _ =

Bassin Zaza (Pump) Min. Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001995-1996 0.20 0.90 0.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 0.001996-1997 1.00 1.00 1.00 1.00 0.00 1.00 1.00 0.00 0.00 0.00 0.00 1.501997-1998 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001998-1999 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.001999-2000 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.30 2.302000-2001 2.30 1.80 0.00 0.00 2.30 0.00 2.30 0.00 0.00 0.00 0.00 2.302001-2002 1.50 1.30 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.302002-2003 2.30 2.30 2.30 2.30 0.00 0.00 0.00 0.00 0.00 0.00 0.00 .002003-2004 2.30 1.90 1.80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Bassin Zaza (Pump) Max. Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001995-1996 0.20 1.00 0.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 0.001996-1997 1.00 1.00 1.00 1.00 0.00 1.00 1.00 0.00 0.00 0.00 0.00 1.501997-1998 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.001998-1999 1.00 1.00, 1.00 1.00, 1.00 1.00, 1.00 1.00 1.00, 1.00 1.00, 1.001999-2000 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 2.30 2.30 2.30 2.302000-2001 2.30 2.30 2.30 2.30 2.30 2.30 2.30 2.30 0.00 0.00 0.00 2.302001-2002 2.30 1.50 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.30 2.302002-2003 2.30 2.30 2.30 2.30 2.30 2.30 0.00 0.00 0.00 0.00 0.00 2.302003-2004 2.30 2.30 2.30 0.00 0.00 0.00 0.00, 0.00 0.00 0.00 0.00 0.00

St. Amand Pump Mean Monthly Flow (cusec) -

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct1994-19951995-1996

=1996-19971997-1998 . .

-1998-19991999-2000

.. -2000-2001 1.45 1.45 1.45 1.45 0.36 0.00 0.00 0.00 0.36 -

2001-2002 1.09- 1.45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.732002-2003 1.45 0.58 0.00 0.00 0.00 0.29 0.00 0.00 0.00 0.00 0.00 0.362003-2004 1.091 1.451 1.45

St. Amand Pump Min. Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-19951995-19961996-19971997-19981998-19991999-2000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

2000-2001 0.00 0.00 0.00 1.45 1.45 1.45 1.45 0.00 0.00 0.00 0.00 0.002001-2002 0.00 1.45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002002-2003 1.45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.002003-2004 0.00 1.45 1.45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

St. Amand Pump Max. Monthly Flow (cusec)Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

1994-1995 _ _

_______ _______1995-1996 _ _l _ _l _ _ _fi r _____1996-1997

1997-19981998-19991999-2000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00o 0.00 0.00o 0.002000-2001 0.00 0.00 0.00 1.45 1.45 1.45 1.45 1.45 0.00 0.00 0.00 1.452001-2002 1.45 1.45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 145I2002-2003 1.45 1.45 0.001 0.00, 0.00 1.45 0.00 0.00 0.00 0.00 0.00 1.452003-2004 1.45 1.45 1.451 0.00o 0.00o 0.00 0.00o .0 0. 0.00 0.00 0.00

Chambre d'Agriculture de I'lle Maurice

REPORT ON THE WATER RIGHTS

OF THE

SUGAR FACTORIES OF MAURITIUS

S. 1. G. M. A.SOCIETE D' INGENIEURS-CONSEILS

PORT LOUIS

December 1978

S.l.G.M.A. - 64 -

SUMMARY

The water rights of Mon Tresor & Mon D6sert Estates aretabulated hereunder.

EstimatedSource Quantity Authority Nature Utilisation(cusec)

Riv. la Chaux 2,4 L.C.O. 13.8.1828 Permanent IrrigatiorDeux BrasCanal

Riv. la Chaux 10.0 S,C.R. 2431 Provisional FactoryPlaisanceCanal

S. I.G.M.A. - 73 -

SUMMARY

The water rights of Riche-en-Eau S.E. are tabulated below

EstimatedSource

Quantity Authority Nature Utilisation(cusec)

R. des Cr6oles L.C.0. 27.11.1865 Provisional Factory &

Irrigation

R. Eau.Bleue L.C.O. 27.11.1865 Provisional Factory &26.o .Irrigation

Ruis. Jocet L.C.O. 27.11.1865 Provisional Factory &S.C.R. 31558

Irrigation

R. des Creoles S.C.R. 26799 1970 Provisional Factory &

Irrigation

R. la Chaux 3.24 L.C.O. 30. 8.1818 Permanent IrrigationS.C.R. 1202

R. B6e-Manique 5.47 L.C.O. 27.11.1865 Provisional Irrigation

R. la Chaux 1.07 L.C.O. 25. 7.1867 Provisional Irrigation

R. la Chaux S.C.R. 23861 Provisional Not used

(Canal de Nil S.C.R. 2431Plaisance)

Ruis. BeauDesert & Tire-

S.C.R. 1455 Provisional Nil

balle

Glaise 0.55 S.C.R. 2156 Provisional

Nil

CENTRAL WATER AUTHORITY MINISTERE DE LA COOPERATION

ETUDE D'UN SCHEMA DIRECTEURD'AMENAGEMENT DES EAUX A L'ILE MAURICE

ETUDE HYDROLOGIQUE

VOLUME 1

HYDROLOGIE DE SURFACE

SEPTEMBRE 1981

SIGMA SOGR EAHIng6nieurs Conseils Ing6nieurs Conseils

L'etude du bilan d'Eau Bleue et de la Rivibre des Cr6oles demande-rait un travail plus detaille, qui 6chappe au cadre de ce Sch6maDirecteur. Mais nous pouvons 6tablir le bilan sommaire ci-dessous,en mayenne annuelle pour 1955-1965 :

- Ruissellement net induit a G9 : 76.946 MCM- Prelbvements des Riverains 4.590 MCM- Pluviometrie totale

106.020 MCM- ETR + ICV 35.893 MCM

81.536 MCM 70.127 MCM

On voit que la pluviometrie, lorsque l'on tient compte de 1'ETR etde 1'interception par ls couvert v6gqtal, ne suffit pas b induire116coulement constate tant & G9 qu'aux prises. Le ddficit, soitde l'ordrs de 11 MCM/an, proviondrait do la recharge souterrainedu haut bassin versant, qui potentiellement, apporterait 38 MCM/an.

RIVIERE LA CHAUX (Figure 2.8)

La Riviere La Chaux a son point de d6part a Nouvelle France ; elleest form&e par plusieurs ruisselets drainant la region sise entrele Parc aux Cerfs et le village du 18bme mile. Elle est travers6epar la Route de la Savanne alors qutelle descend au sud est pourobliquer vers l'est et croiser la route de Rose Belle qu'elle longepratiquement jusqu'a l'usine de Rose Belle.

Par jugement du Tribunal Terrier en date du 2 fevrier 1866, undroit provisoire fut accordd aux sucreries de Rose Belle et UnionPark, h prendre 0.107 m3/sec (3.786 pd3/sec) de la Riuibre La Chaux.Ca droit prouisoire n'est plus exerce.

Ella est grossie par plusieurs contributions mineures, dont leRuisselet Union Park. Au nord-est de le sucreria de Rose Belle,elle est rejointe par le Ruisseau Constantin et peu aprbs, au niveoaudu pont de l'ancien chemin de fer, par l Rivibre Cee Varangue, unde ses principaux effluents, issue de la r§gion do Nouvelle Franceet else mame grossie par dioverses contributions mineures, dont leRuisseau Bambous.

La Cour Suprame, par jugement No. 25917, autorisa b titre provisoirs,les sucreries de Rose Belle, Mare d'Albert et la Rosa, b prendre 1/3du ddbit do la Rivibre Bee Varangue. Cette autorisation fut subs6-quemment amendee le 20 aoOt 1904 par la m6me Cour (SCR No. 29253)qui transferra les droits de prise de l Riviere' Be Varangue a leRivibre La Chaux, a l requAte du Mauritius Estates and Assets Com-pany Limited. Une digue construite sur la Rivibre La Chaux permetla deviation d'environ 0.057 m3/sec (2.01 pd3/sec) destinee auxfonctionnement de l'usine de Rose Belle, l'eau itant ensuite retour-nee a la Riviere.

La Rivibre La Chaux contourne l'agglom6ration de Rose Belle par lenord et se dirige vers Astroea, qu'elle atteint apres avoir regu leseaux du Ruisseau Baramee, issu de la r6gion de Pont Coleville, etdes ruisseaux Queen, Carlin, Pavoine et Pont Fer. C'est a Astroeaque la Rivibre La Chaux est rejointe par un autre affluent important,la Rivibre Bee Manique, qui a longtemps servi, de meme que la RivibreBee Varangue, avant la construction du r6servoir de Piton du Milieu,a L'alimentation en eau potable au sud de l'ile. Les digues servantde prise a cet ancien r6seau, se voient encore sur les rivieres L6eManique et Bee Varangue. La rivibre prend source dans la rbgion duMont Pauline. dans l'ouest de Cluny. Ella est grossie par las con-tributions des Ruisseaux Marron, Clair et de la Pompe, de la RivibreMapou, des Ruisseaux Mariette, Terre Glaise (ou Eau Bleue) et Pourri,contourne le Piton de Rose Belle, par le sud et se jette dans laRivibre La Chaux un peu en amont du Pont d'Astroea.

L'eau de la Rivibre B6e Manique a deja fait l'objet de jugements duTribunal Terrier et de la Cour Supreme. Un premier jugement duTribunal Terrier en date du 27 novembre 1865 autorisa le domainssucrier de Riche en Eau i prelever 0.155 m3/sec (5.47 pd3/sec) surla Riviere See Manique. Ca prAlbvement se fait au mayen d'un canalpartant au pied du Piton de Rose Belle, aussi appele Mont Vernon etsert 6 l'irrigation.

Un second jugement de la Cour Supreme, an date du 27 avril 1939 (SCRNo. 2156) accorda, a titre provisoire, le droit a la CompagnieSucriere dc Beau Vallon, de prblever 0.050 m3/sec (1.76 pd-/sec) surla Riviere See Manique et 0.010 m3/sec (0.353 pd3/sec) sur le Ruis-seau Terre Glaise (ou Eau Bleue). Ces autorisations peuvent etreconsiderees comma mises an application a des prises consenties a cestitulaires an aval d'Astroea sur la Rivibre La Chaux. Le domainesucrier d'Eau Bleue, aujourd'hui annexe de la Sucrerie de Rose Bella,recut le droit provisoire par ordre du Tribunal Terrier en date du2 septembre 1879, de prelever 0.003 m3/sec (0.167 pd3/sec) des eauxde La Rivibre B9e Manique. Mais ce droit n'est plus utilise parRose Belle.

Par un jugement du Tribunal Terrier en date du 13 aoGt 1828 (Ref.Archives de Maurice, Vol. L.A. 10/33), la concession de Louis leGrand de Cherval obtint le permission de dsvier 0.068 m3/sec (2.4pd3/sec) de la Riviere La Chaux, au moyen de ce canal, pour lefonctionnament des usines de MM. de Cherval at Bertrand. Ces con-cessions furent achetees par la sucrerie de Mon Dbsert Mon Tresorqui h§rita donc des droits d'eau qui leur §taient attaches. Ladeviation s' effectue-pai le Canal dc 'Daux Bras' (au Canal' Sauzisr)dont la tAte se situe an amont du Pont d'-Astroea.. L'eau estretourn6eea le Rivibre La Chaux, an aval du Pont.

Le debit residuel de la Rivibre La Chaux est jeuge a la station Hlau Pont d'Astroea.

A ce pont, un site de barrage a et identifi§ et utilise dans unsbtude (SIGMA, d6cembre 1977) pour la Fourniturs d'un debit de 0.737m3/ssc a une usine de pate a papier envisagoea la sortie du coursierd'bvacuation de la centrale hydro-dlectrique de Ferney. Le Reservoird'Astroea aurait une capacite brute de stockags de 4.250 x 106 m3

(150 MCF). Une sortie compensatoire §quivalente au d6bit normal dela Rivibre La Chaux, garantirait aux riverains en aval, l'eau alaquelle ils ont droit. Le Reservoir d'Astroea permettrait unerdgulation des crues de la Riviere La Chaux et partant, une devia-tion suppleant aux contributions de la Rivibre des Creoles et duRuisseau Tranquillea llusine de Ferney. La capacite optimale ducanal de deviation fut etablie a 2.834 m3/sec (1QB pd3/sec) apresune btude economique. Ce projet aurait garanti, non seuleamentl'alimentation regulibre de l'usine de p&ite 3 papier, mais encore,aurait parmis la production annuelle d'llectricit6 de Ferney d'aug-menter de 4.72 GW/heure en moyenne. Aucune suite ne fut donn6a auprojet papier. Mais les sucreries de Riche en Eau et Mon DesertMon Tresor, riveraines et ayant des droits sur la Rivibre La Chaux,ont rbcemment manifeste laur interbt dans le projet de barrage aAstroea, qui alimenterait gravitairement leurs raseaux d'irrigation.Le projet d'Astroea sera repris en detail dans le deuxibme partie.

Apras Astroaa, la Rivisre La Chaux resoit les contributions desRuisseaux Quirin, Deux Bras, Cimeti6re, Guilmar, St. Romain,Tiraba-•Llle et Beau Ddsert et d'autres encore, point nommes. Aprbsun parcours sinueux et escarpe, elle ast endigu6e 8 environ 3.25km en aval d'Astroeaetde;cette digue en pierre de taille construiteen 1888, part le Canal de Plaisance, initialement destine au fonc-tionnament de la sucrerie de Plaisance. Par jugement de la CourSupreme en date du 18 mars 1887 (SCR No. 23B61) la dite sucreriaregut permission provisoire de dovier -41 du dbbit de la.Rivibre LaChaux a la digue. Plus tard, en date du 14 fevrier 1921, la CourSuprbme (SCR No. 33024) autorisa M. Ambdae Hugnin a sur6lever de12.70 cm le seuil des quatre ouvertures pratiquees dans la digue.La Compagnie Sucriere de Mon Dessrt Mon Tresor fit,subs6quemment,l'acquisition du domaine de Plaisance, at, 1B 23 juillet 1940, laCour Suprsme autorisa, conjointement avec la Compagnie Sucribre deBeau Vallon, a devier par le Canal de Plaisance 0.35 du debit dela Rivibre La Chaux au lieu des 0.25 initialement accordes.

Le debit du Canal de Plaisance fut alors partag6 entre les deuxcompagnies sucrieres, cella de Mon Desert Mon Tresor prelevant0.786 et celle de Beau Vallon, 0.214 du debit. La part de MonDesert Mon Trdsor lui sart a l'op6ration de l'usine a sucre dumeme nom, aprbs un parcours de 4.512 km constitu6 de sections enterra battue, en magonnerie et en prefabrique. Les partes sontconsiderables au long des 1829 m du parcours en terre battue, enmauvais etat. I1 fut question de remplacer ce canal en terre paruneacanalisation forcee mais aucune suite n'a ete donnee b ceprojet. La part de la Compagnie Sucribre de Beau Vallon, dastinseb l'irrigation des annexes de Ste Hl1bne, n'est actuellement pasutilis6e par cette compagnie, ce qui fait que Mon Desert MonTrrsor a jouissance exclusive de Canal de Plaisance.

II faut remarquer que la Compagnie de Beau Vallon fut autoris§e8 titre provisoire, a prendre 9/10 de l'eau des Ruisseaux Tireballeet Beau Desert, tributaires de la Rivibre La Chaux, par jugement dela Cour SuprOme en date du 27 fevrier 1936 (SCR No. 1455). Mais cedroit n'est pas mis en application. Aprbs la digue de Plaisance,La Rivibre La Chaux est grossie par les Ruisseaux St. Roch,Solitude, Calebasses et Cantin, et par la Riviere Copeaux, et, aenviron 1.25 km avant de couler 8 Beau Vallon, est endiouee une

nouvelle fois pour permettre la prise du Canal de Beau Vallon. LeTribunal Terrier, par jugement en date du 30 aoGt 1818, autorisaM. J.3. de Rochecouste, propri6taire de Beau Vallon, a construirece canal appel§ Canal de Mahebourg, qui devait recevoir 500 poucesfontainiers (soit 3.85 pd3/sec ou 0.110 m3/sec) partageable commesuit .

b M. de Rochecousteproprietaire de Beau Vallon : 0.033 m3/sec (1.16 pd3/sec)

* M. de Robillardpropri6taire du domainede la Rivibre La Chaux : 0.033 m3/sec (1.16 pd3/sec)

* b La Ville de Mahebourg : 0.044 m3/sec (1.55 pd3/sec)

Plus tard, le 2 decembre 1935, par devant la Cour Supreme (SCR No.1202), le Conseil de District du Grand Port, au nom de la Ville deMahebourg, renonga a sa part du Canal de Beau Vallon au profit dela Compagnie de Beau Vallon. La deviation fut en mtme temps reduitede 500 b 439 pouces fontainiers. La Compagnis de Beau Vallon, enconsequenca, devint l'unique utilisateur des eaux du canal, jouissantd'un droit permanent et s'en servant pour l'irrigation de cannes 6sucre a Beau Vallon. Un jugement du Tribunal Terrier, en date du 25juillet 1867, accorda, i titre provisoire, a la Sucrerie de BeauVallon, une part se montant a 0.030 m3/sec (1.06 pd3 /sec).

Aprbs la prise du Canal de Beau Vallon, la Rivibre La Chaux recoitencore les contributions des ruisselets Alfred et Beau Vallon, passea proximitb des ruines de la sucrerie de Beau Vallon od elle estjaugea N la station H2 et se jette a la mer a la Pointe de la Colonie,traversee, juste avant son embouchure, par le Pont de la Rivi2re LaChaux, reliant Mahebourg a la Ville Noire.

Les modalites de partage de la Rivibre La Chaux, en aval de la diguede Plaisance, selon les provisions de l'Ordonnance 35 de 1863, furentsuggeress par Arthur Langlois, arpenteur jure, dans daux rapportsdat6s du 1 decembre 1893 (SCR No. 26045). Ces rapports n'ont pas dt6homologues per la Cour Suprgme, bien qua prdsantant un partage raiso-nable des eaux de l Rivi2re La Chaux, selon les lois en vigueur.Finalement, le 4 novembre 1975, le debit normal de la Riviere La Chauxa Beau Vallon fut etabli par l CWA, selon la methods des isohybtessur le bassin versant, a 0.843 m3/sec (29.76 pd 3 /sec), en accord avecle Rivers and Canals Ordinance d'octobre 1941.

Un plan montrant le systbme hydrologique de la Riviere La Chaux etcelui de la Rivibre des CrEoles est donne dans la figure 2.8.

-78-

2.9.1 Les Stations de Mesure de la RiviLre La Chaux

2.9.1.1 La station HI & Astroaa

Cette station, construite par le Ministere des Trausux et initiale-ment codee M.O.W.4, jauge le debit rssidusl de la Rivibre La Chaux,du fait des prises mentionnees ci-dessus.

L'bquipement consiste en un d6versoir a mince paroi serti dans undeversoir a seuil large, d'une rbgle gradues avec courbs de tarageappropri6e. Les hauteurs quotidiennes moyennes ant donc At6 mesu-r6es manusilement depuis juillet 1954 jusqu'3 octobre 1966. Provi-sion avait 6t6 faite pour la mise en service d'un enregistreur con-tinu MUNRO, mais l'appareil ne fut jameis utilise. La station futabandonnee en 1966. La CWA a copendant recommencd les jeugeagas bpartir de 1974. La disponibilitt des donn6es a Hi peut se r6sumerdans le tableau 2.9.1.1.1. ci-dessous.

Tableau 2.9.1.1.1. : Disponibilite, Origine et Qualite des donnhasa Hi 6 Astroea

DEBITS MOYENS QUOTIDIENS A HIPERIODE

ORIGINE QUALITE

Juillat 1954 Ministbre des Travaux, Fiable- Octobre 1966 masures manuelles

Novembre 1966 - 1974 N6ant

1974 - 1980 CWA Fiable

Nous n'avons pas g6n&re les donnees manquants pour la p6riode 1966-1974. Touts corr6lation avec la Rivibre des Creoles est impossiblecar les donnees font defaut pour cette rivibre aussi. Et mbme sielles existaient, La Rivibre des Creoles ost regulee par le R6ser-uoir d'Eau Bleue alors que le debit de la RiviAre La Chaux estnaturel. Nous avons essaye une g6neration utilisant la Rivibre duPoste & Pont Coleville comme base, mais les resultats n'ont pas 6t6concluants.

2.9.1.2 La station H2 i Beau Vallon

Le dsversoir est du type CRUMP, avec une echolle limnimetrique snre-gistreur STEVENS et courbe do tarage appropri6s. Cette stationexistait depuis 1966, car des essais furent entrepris dBs novembre1966. Mais ella n'stait exploit(e qu'occasionnellement. La CWAconserve des donnees la concernant depuis f&vrier 1974. Elle mesurele debit residual de la RiviAre La Chaux, an aval des diverses d6via-tions d6crites plus haut.

2.9.2 Analy_se_ des debits de la Rivibre La Chaux & Aastroea

2.9.2.1. Regime Pluviomdtrique

La station Hi a Astroea, controle un bassin versant recouvrant unesuperficie de 32.8 km2, dont la majeure partie se trouve a unealtitude oui la pluviom6trie est trbs forte, figure 2.9.2.1.1. Lastation de la Peyre est bien plac6e pour donner la pluviom6triemoyenne sur la partie sup6rieure, et celle d'Astroea, sur la partieinferieure. Les donn6es pluviom6triques d'Astroea sont compar6esavec celles de Piton du Milieu, figure 2.9.2.1.2.

Malheureusement, lexploitation de La Peyre fait defaut pour lesannees 1958-1960. Nous l'avons completea par comparaison avec LaChartreuse, voir figure 3.1.3.1.3. plus loin.

Nous evans ensuits calcule la pluviom6trie ponderee sur les 32.8km2 du bassin versant, affectant 18.6 km2 a Astrosa et 14.2 b LaPeyrs. La comparaison, par double masses, des apports annuels dela Rivibre La Chaux a Astroea, at des volumes pluviomdtriques pon-d§res annuels sur son bassin varsant, est donnee dans la figure2.9.2.1.3.

En ce qui concerne la relation Ruissellement annuel - Pluviomdtrieannuells, nous avons etabli la suivante

Q = - 18.299 + 0.460 PR2 = o.69s

ou Q - apport annual de la Rivibre La Chaux & Astroea (MCM)P = volume pluviomOtrique annuel sur le bassin versant (MCM)

R2 = coefFicient de d§termination lineaire.

En faisant Q ^- 0, on a Po = 39.762 MCM.

Sur ce bassin versant de 32.8 km , a forte pluviometris, ETR + ICVannuelle moyenne serait de l'ordre de 40 MCM. Les ordres de gran-deur sont donc respect6s.

I1 convient de preciser que les debits mesures a Astroea ne repre-sentent pas le ruissellement naturel du haut bassin versant de laRiviere La Chaux, a cause des prises de :

Riche en Eau, sur la Rivibre 86a Manique, qui se monte a 0.155m3/sec (5.47 pd3/sec) ,

Mon Tresor - Mon D6sert, sur la Rivibre La Chaux, qui se montea 0.068 m3/sec (2.4 pd3/sec)

par le Canal de Deux Bras.

IC MA Soc:iete d'Incgenieurs Conseil%SCHEMA DIRECTEUR D'AMENAGEMENT DLS EAUX

DEBII MOYEN MENSUEL DE LA RIVIERE LA CHAUX A ASTROEA [HI] UNITE=pd3/sANN.EE JAN FEV MAR AVR HAL JU JUI AOU SEP OCT NOV DEC1955 13.65 70.30 95.00 81.30 60,03 72.17 43.42 34.41 26.13 15.94 9.93 29.761?56 67.17 93.56 90.27 44.84 37.63 45.85 21.73 17.02 12.43 8.92 7.22 28.501957 45.69 49.95 53.93 102.92 45,00 42.85 20.45 15.19 13.74 10.56 8.46 16.6119S8 61.48 72.99 152.25 173.11 117.10 43.61 70.51 39.84 26.18 21.62 11.81 8.011959 26.88 88.36 106.55 55.18 31.80 14.96 11.60 48.46 34.56 46.87 81.27 53.171Y60 97,15 113,02 142.57 74.59 24,12 38.07 30.52 17.91 48.67 28.49 18.12 12.921961 14.59 10.49 13.67 27.16 17.66 17.78 34.07 42.83 49.01 15.30 9.93 218.351962 128.00 134.09 153.73 90.84 33.50 46,82 20.94 14.13 27.01 37.29 38.71 21.041963 26.19 56.85 55.53 94.30 60,15 46.03 50.04 18.32 9.84 13.91 60.95 24.851964 58.70 57.33 83.63 54.76 68.23 46.11 22.95 27.84 27.30 33,63 17.84 14.741965 43.57 55.56 47.01 106.91 63.24 74.96 78.86 63.15 91.43 49,55 53.00 14.47MOYENNE 53,006 72,956 90.376 82,357 50.768 44,474 36.824 30.826 33.300 25.643 28,831 40.222

ECART-TYPE 35,278 33,540 46.045 39.360 27.757 18.267 21.782 16.250 23.260 14.461 25.648 60.335

SIGMA Societte 5dIngeniie urs Const-i3ils

SCHEMA DIRECTEUR D AMENAGEMENT DES EAUXDEDIT MOYEN MENSUEL DE LA RIVIERE LA CHAUX A ASTROEA (HI] UNITE=pd3/sANNEE JAN FEV MAR AVR MhAL JU JUI AOU SEP OCT NOV DEC1975 11.42 64.50 56.21 46.19 66.54 39.45 23.30 18.64 26.37 13.88 13.36 9.03

1976 10.48 108.03 55.72 60,63 84.13 86.29 41.03 32.25 21.36 15.25 12.71 12.361977 43.50 66.95 15.82 80.64 71.81 43.88 23.23 18.47 13.70 15.15 9.82 23.701978 41.21 33.71 41.53 48.67 35,65 25.69 31.55 40.65 24.96 14.13 16.59 8.671979 29.38 85.33 74.46 47.62 52.83 60.47 29.36 40.22 33.25 16.43 13.34 46.701980 137.70 106.75 118.02 105.99 59.55 37.66 33.40 28.52 22.91 22.59 16.81 24.55MOYENNE 45.613 77,545 60.295 64.956 61.751 48.908 30.309 29.78? 23.760 16.238 13.770 20.a35

ECARr-TYPE 47.268 28.448 34.354 23.943 16,677 21.503 6.724 9,867 6.419 3.241 2.619 14.491

M I ( , S.; o C:: 3. i t 1 l cL ' ;1. ri g c n *? :'. * kU r, t-i C c) n 1. :ISCHEMA DIRECTEUR D'AMENAGIMANI DES LAUXANALYSE DE:S IDEBITS DE LA RiVIiRE LA CI-AUX A ASIVIOLA L.HII POUR 177j-1l980

DEBIT MOYEN QUOTIDIEN POURCENTACG du FKEQUENCE d'OCCURENCEM3/sec pd3/isec DEBIT fOTAL % du Nb de JAUGEAGES.085 3 1l0.0 100.0.141

I 1 0 0 . U.283 10 98,76 93.93.424 AS 94,00 78 I 0.566 20 88.73 65.42,/07 .j 83s.2 i 55. .4.849 30 77.b5 46.991.132 40 6.6'I 34.031.415 50 54,99 23,451.698 60 46.83

17.,291.981 70 39.38 12.552 . 264 o0 33.982.547 90 30.39 7.892.830 100 26,81 6.-4-3,537 125 20.82 4.11Al.245 1 50 17. Ob 2.974.952 175 13.84 2.14b.660 200 12.82 I.9{227.075 250 10.14 1.418.490 .l) 0 8.02 1.091 1 .320 400 0 00 0 . 0014.1S0 :;0o 0 00 0 0016.980 600 0.00 0 0019,810 700 0.O0 0,0022.640 800 0.01 0.00

3:, :1: G Si 4 ) ",o :: :L o t e cl I n cj e- :i. :. u r '5 C; o n - o-e i. 1. .i-

SCHEMA Il)tCTEUR D'VAMENAGEMENI' DES EAUX

ANALYSE DLS DEBITS DE LA RIVIERIL LA CHAUX A ASTRJLA [HI] POUR 1955-1965

DEL;IT MOYEN QUOf'IDIEN POURCENTAGE' du FRLEUENCE d'OCCURENCEm,S/sec pd,3/sec DEBIT 1[0U AL Z du Nb de .fAUGEAGI S

.0135 3 100.0 100.0.141 100. 99. ll, 98.283 10 98.82 92.88.424 15 ?5 . b Y 80.01.566 20 92.06) 70.03./707 25 8e8a 4'r 62. 2020.849 30 85. 15 56.251.132 4l 76.41 43.93

1,415 50 66.32 32,931.698 60 07.12 2!4. 641.981 70 51.73 20.56-2624 80 46.O9 1 6.8.547 90 41.44 14.19330 lll0 :3.1 9.883J537 1.25 215. 30 6.45

4.24b I 1 S 1 9 9 8 4. 4184.952 175 16.12 3.36

200hh OU 11.84 2.247/,075 250 7.86 1.348,490 ,0 0 4.2, .70

100

(78-79)_7778)E

(76 -.77)E

( -76)

17-75)O 75 ------ (73 74)

(72 - 73)

(71 2)o -

(7X0-71) 7

(-69-70)< -

(6-68)'0

/(66-67)x,, 50 - -65-66)

(64 65

(62-63) PA t95t914 0-95S BR 3'W(61-62) R2 = l.000

C - (6061)a 25 -(-9-60) - -- . .

c58-59)O 20

I I (56-57)

10 (55-)(56./S56;

- i (53 5 2 5 )75 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _X I I .

I S 15 10 15 20 25 50 75 l0oTotaux annuels cumuiltifs a Piton du Milieu (xlO3 mm)

Fig. 2.9.2.1-2: V&eification, par Double-Masse, de I homog6neitedes totaux p(uviom6triques d'Astroea

par rapport a ceux de Piton du Milieu

750

500

Eu

C 2SC

- 20000.

< ISO =0.066+*0.325P

100 -R 2 = 0.999

)00 200 300 400 500 1000 1500Votumes ptuviometriques annue(s cumulatifs,P(MCM)

Fig. 2-9-2-1 3: Comparcison,par Double-Masse,des apports annuelsde la Riviere La Chaux d Astroea avec les volumes

pluviometriques annuels sur son bassin versant

-80-

2.9.2.2 Crues et 6tiages de le Rivi6re La Chaux

Les jaugeages 6 Astroea se font manuellement et il ne nous est doncpas possible de pr6ciser lee d6bits de pointe aux grandes crues.

Dans las donndes disponibles ne figurent pas celles des stiages de1968-1969 et 1974-1975 qui sont reputes s6vbres.

Les crues moyennes sont indiquees dans le tableau ci-dessous.

Tebleau 2.9.2.2.1.

bit de Crue M9yennes de 24 houreDate.de la Crue -d/9 .l/-

pd3/sc m3/ec

28 fevrier 195279.0 7.91|uB f6vrier 1956 273.6 7.7504 avril 1957 280.0 7.9302 avril 1958 286.0 8.1008 mars 1959 216.0 8 6.1214 novembre 1959 300.0 8.5D04 septembrel961 21D.0 5.9507 fbvrier 1962 300.0 8.5025 fevrier 1963 ' 300.0 8.5020 janvier 1964 300.0 8.5024 mars 1965 300.0 8.5006 fevrier 1975 300.0 8.5020 juin 1976 300.0 8.5010 fevrier 1977 300.0 8.5021 janvier 1978 300.0 8.5003 fevrier 1979 295.D 8.3623 d6cembre 1979 j 300.0 8.50 1

I1 samblerait qua les crues n'aient pas ete bien jaug6es et quepour les reprssenter, on ait adopte une limite superieure de 300pd3/sec (8.50 m3/sec).

Pour les btiages, les fluctuations, a l' chelle du jour, sont quasin6gligeables et an doit pouvoir se fier aux mesures publiees. Mais,etant donna les lacunes dans les series de jaugeages an particulier,pour les saisons sbches historiques 68-69 et 74-75, toute pr§visionde fr6quence de retour d'un d6bit dl6tiags donna devra etre inter-pretee avec prudence.

Nous avons relev§ les debits d'etiage suivants

Tableau 2.9.2.2.2-

BBa Dbbit d'etiage minimumHrnngi Date d'ObservationHydrologique pd3 /sec li/sec

1955-1956 27 octobre 1956 6.50 184

1956-1957 22 novembre 1956 6.30 1751957-1958 24 novembre 1957 6.80 1931958-1959 04 decembre 1958 4.80 1361959-1960 01 septembre 1960 13.40 380

1960-1961 13 decembre 1960 6.80 1931961-1962 07 novembre 1961 8.40 2381962-1963 30 octobre 1963 6.70 1901963-1964 13 janvier 1964 8.60 2441964-1965 01 d§cembre 1964 9.40 2661975-1976 1 18 decembre 1975 6.50 1841976-1977 09 decembre 1976 8.72 2471977-1978 22 novembre 1977 8.72 2471978-1979 06 janvier 1979 6.10 173

1979-1980 08 decembre 1979 10.00 283

Nous avons effectue une analyse de frequence at la droite de Galton-Gibrat est celle qui, dans les circonstances presentes, donne lemeilleur ajustement, rigure 2.9.2,2.1.

Nous trouvons, Log g = 0.8814 + 0.1094 ZoC g = debit d'etiage

Z = variable de Gauss.

En l'absence de mesure pour les etiages de 68-69 et 74-75, nousdeduisons, b partir de la Figure 2.9.2.2.1., les fr6quences deretour des debits suivants :

4.5 pd3/sec : 1 ann6e en 100

5.0 pd3/sec : 1 annee en 25

7.5 pd3/sec-J 1 annee sur 2

Periode de retour T annees D 10 20 50 100 200 500 Soo0

30

20

.0

2

0 000 0 0 0 0 4 . 00 00 0 ut) to a

-N m4 0 0n O .. 0 0

co ai c a't V 0 el i 1.-- 10

1 2 3Variable de GAUSS (Z)Riviere La Chaux c Astroea. (HI)

Fig. 2.9 .2. 2.1: Ajustement d'une Fonction de GALTON - GIBRAT aux debitsd'etiage de ta Riviere La Chaux 6 Astroea (Hi)



APPENDIX F - Septic Tank & Leaching Field

C.il Von Cover

LEWater Level

Water Level Wote, Level

090 UPVC 090 UPVC

SECTION A-A \ g Layer SECTION B-B SECTION C-C

.3700

200 750 1501500 s150 750 20 t

-- --- - -- - -- - - -- - - - ------------ ----INLET

INLET --. , , *,,, ,,,- -3

COMPAGNIE THERMIQUE.' > ! !.> >. !, .DE SAVANNAH Ltd.

-- -- - - -----

Construction & Operation of a83 MW CoallBagasse-Fired Power Plant

at Sai'an,nah-_ __ .Septic

Tank DetailsS"cal 1 25

Dale Jove 2005--. '

Job No. 2436PLAN OF SEPTIC TANK S.I.G.M.A. -Ove Arup & PartnersAssoaiated Consulting Engineers

19 Ch-hv Street - Pal L..y- M-frO~Tel 212 373405 212 096r2 212 2145 FaOo(230)205 0375

4500EAT

<NHe-------- -----m------- L - >GETEXTILE MEMBRANE

GRAVEL:20/40

SLOPE 2mmrm PIPE_

090mm UPVC PIPE MANHOL SLOPE 2mrrm

GRAVEL:20140

|~~ -3 ReFRRR-PC0 - - - - - - - - - - - - -d

SLOPE 2mrm

RCKAN

P~ERFORATED PIfPE PVC 090nmmX

PIPE ARRANGEMENT OF LEACHING FIELD

TRENCH FOR PERFORATED PIPE


Construction & Operation of a83 MW Coal/Bagasse-Fired Power Plant

at SavannahLeaching Field Details

S'ale 125i

Dale J-ne 2005*i 0 °Job

No. 2436Details of Perforated Pipe PVC 090 S.I.G.M.A. - Ove Arup & Partners

Associated Consuling Engineers

19 C42tC Street- 212 L-an -Maul nsTel 212 3734/5 212 0962 212 2145 Fa. (230)208 0375



APPENDIX G - Wind Roses at Plaisance

I JANUARY 7 I,

If FE13 0 Yj ! , --, '1 - sc

\ >ei; t/ ,,- 1, lb,-

OC[ENESCL CASPNjIRNE m)INLVLCIYCLSE

2 - - < I .5 -8 - <I - 12 -4

O S >LS 1 C1 2 35-< FIGURE B (a) - MONTHLY WIND DISTRIBUTION FOR SITE01 5 10 %

8 325- <55- (DATA FROM PLAISANCE STATION (1 971-90))

I- jl

t F :..A ,tFJ

4.,MAYt f>r , 1t . > ' ' .' -. s~' ; i..r) - J E , . ;, Ir 2 ; * p1 ;.

o 'I' '_ .7 '~ _____ -Z "

-- __ _--

-. --. -. - --- -- N .-- - --I4L .ASAi , .y. i .

.-- . . As A ac

t - :. K s

IF 'F IA . 4 - t1| -- - A. -A -?

-- K0Q \-s 2--? -- -z ----

4@;4 9.-t

4 s -. A s - 3 S 1 . K:5;r,. || - - . - --

OCCURENCE SCALE "LAS 10CEtlY WIND VELOCITY CLASSES2- 5 S23 -< FIGURE B (b) - MONTHLY WIND DISTRIBUTION FOR SITE01 5 1O~~~~ 3s5- <a FRMPASNC5TTO01 5. 315(DATA FROM PLAISANCE STATION (1971-90))8 -10.5 123456

>10.5

L .i*11PtEMEL. BR --CTBER

i-fV* E, I X,C ;i , '

- - - s- -- -. - . --- - --- --- -, I

OCCURENCE SCALE CLA S S ANEL m . WIND VELOCITY CLASSES

0 -t L /2

_ |2°-c32 FIGURE B (c) - MONTHLY WIND DISTRIBUTION FOR SITE551 %5 <.35 - < a0 24 (DATA FROM PLAISANCE STATION (1971-90))

5 8 < 1.5 12 3 5K6 > 10.5

Compagnie Thermique de SavannahOperation of a dual coaUbagasse-fired Power Plant


APPENDIX H - Gaseous Emissions from Bagasse

FACULT7 OF ENGINEERING; Jt: eF FacLdrv- . Tel .i3(j0 454 1041 Et. 7 22(~ 230 , 464 9 S8

Fretitss' il. C. S. Rughoi ilutil, Phit)EJ .- ec.to: Ljcs and CoC)rLILrucutiorns

I October 2003 -.

MNr Gerard Rault -

Operation ManagerThe Savannah Sugar Estate ,- 1I'e.scalie.r

, ear Sir.

Rc: 'lest lResults Report On Stack Emission and . rubient Air Quality

Thank you foir haying participated in the air emissions monitoring program for sug,arfactories for the lililling season 2003.The support and help given to us in the factorypremises by your staff have been highly appreciated.

Thfe monitoring team conducted tests for stack particulate matter, gaseous emissionsWid ambient air auaiity from 2 9 'd July to l8I' August 2003 in the factory. Results arcC;ven in the enclosed report prepared by the p-.oject engineer.

W e hope that our- services have been to your satisfaction and Ce remain at yourdisposal for an> further information clarification.

; v;7S faithUi-i.-j.

Professo CS RughooputhChairman. Manaoernent ComminitteeAir pollution Monitoring UJnit

j '. EDUIT, MAUR!TIUS -

13-JbN-2r00 11:1 2 6262640 P-02

Recognitionl of Testing Proceduresu o ests rave been carried out as recorrmmernded and, ap).oved by tne Code of Federar Reguiations 40 of tile

Unjted Slates Environment Protection Act 1996

Methodology of Testing

A - Testing procedures for Ambient Air Quality are given in the US EPA CFR 40 Part 53Armbient air is continuously sampled and fed into analvsers for NO1. SO2 00, C. and PM lo

The dry measurement method is based on the absorption and emission properties of the different gases onelectromagnetic waves at particular wavelengths. The measurement principles of the gases are

NO, Chemiluminescence's0°2 Fluorescence

CO tRiAbsorption02 Ctiemiluminescence'sPM1o High Volume Sampler

1 ziazt concentration values are averaged at every 15 minutes and recorded in a data fogger

B- Testing procedures for Stack Gaseous Emissions are given in the US EPA CFR 40 Part 60Flue gas is continuously sampled under vacuum from the chimney through a heated line to avoid condensation, It isfiltered, its moisture condensed out and then fed into analysers for NOX, SO2 CO, 03 CO2 and 02.

The method of measuremInt, on a dry basis, for each gas is:

t40l Chemiluminescence'sSO2 LIVIIR AbsorptionCO IR AbsorptionC2 IR-Absc-ption02 Para magnetism

C - Testing procedures for Stack Particulate Emissions are given in the US EPA CFR 40 Part 60The flue gas is sampled firom the chimney at the same velocity ol its exhaust via a heated filter. The particulatematter is caught on the filter and af7.er its moisture has been condensed out, the volume of dry flue gas sampled isrecorded. The mass of particulate matter caught is determined and the particulate load is calculated with respect toIre volum.e of flue gas sampled.

Quatity Assurance and Quality ControlThe Code of Federal Regulations has formulated testing methods that include procedures for Quality Assuranceand Qualitv Control.

Ttie analysers for ambient air measurement are systematically calibrated at zern and span level before and aftermeasurement in a site. Protocol Gases of g9.999 % purity level are used for calibration purposes as recommendedby the Code.

13-JAN--2005 11: 12 6262840 95. P.0-

analyserS for gaseous air emissions are :2:;rr3:ee lr Io, rg a oirec! caitorailon operatlon using rIMlOCOi gases,f e9.998% at zero, mid and span values before and after measurement, A s,vstem calibration (operation performedboth before and after sampling) at zero and span levels to measure bias due to filtration and condensation Zeroand span drifts and system bias are included in the calculation of the emission concentrations.

For partizulate measurement, the high volume sampler is leak checked before and after every run. A m,!m -,m oftwo runs of samplino is carried out to ensure a representative result. The dry gas meter, pitot tubes, nozzles,pressure transducers, therrnocouples and the electronic balances have been calibrated by their respectivemanufacturers and carry calibration certificates.

The sampling is done isokinetically at numerous points (12 to 24) in a region of laminar flows. The number ofsampling points, the fiue gas velocity, the molecular weight and moisture content of the fiue gas is determinedbefore a particulate sampling is done to ensure proper sampling.

Correction and Standardisatioo of Coecentration ValuesAfter a value for the concentration of a gas or particulate matter is obtained by a reference method, the value of theconcentration is corrected to the following standard set of conditions.

Concentration of oases for Stack Gaseous Emissions have been corrected to standard conditions of temperaturer273. 16 K) and pressure t l atmosphere or 101300 Pa) and at 15% 02to correct for excess air. The concentration ofgases is exDressed as parts of pollutant per million parts of dry flue gas.

I

Concentration of Stack Pafticulate Matter has been corrected to standard conditions of temperature (273.1 6K) andDressure 11 atm or 101300 Pa) and at 12% C02 to correct for excess air. The concentration of particulate matter isexDressed as milligrams per cubic metre of dry flue gas.

The tests have been carried out at normal factory operating conditons as described in Table 1: Factory Data andthe test results are given i l Tables 2,3 and 4.

The Standards issued by the Ministry of Environment are given in appendix for comparison purposes.

13-JAN-2005 II:13 62622840 9i4% P. 04

Ruel I gasseBoiler TvDe, John Thompson Dumping GradeScrubber Type Devumprpssion Chamber Wet ScrubberNumber of stacks OneStack Diamdter (340mStack Pressure rance 5-10 mm H20Stack Velocity range 8.0-I2. 0 m/sStack Flow Rate range ! 72 0-1 I O0 m3isAverage Flue Gas Temperature 8 - 70 °C,Fue Gas Mdlecular Weight 13.3 (C12 scale)Flue Gas M6isture Content 15 %rr

TABLE 2: STACK GASEOUS EMISSIONSDATA r-LiL . 'Source of sampling -Ports on chimnevDate -- 131/07/03 - 041/0803Component; Measured Concentration EPA 2002

_ Concentration @15 % 02 Standard !Oxygen, % I 4.8 15 NoneCarbon Dioiide, % 16.0 5.4 NoneSulphur Dioxide, ppm 30- 13 42Nitrogen Di6xidr, ppm 130 15 i 374Carbon Monoxide, ppm 1200 421 800NOTE.Use concentrations @15 % °2 to compare with Emi.qsion Standards

TA1BLE3:STACK PARTICULATE MATTER EMISSiON DATA~Source o [ing iPorts on chimneyDate 3 1 t August 2003Actual Particblate Matter Load , mg/m3 1374.0 .

Particulate Matter Load @ 12% C02, mgtm2Z8WNOTES.1, 'In miltlgrams of particulate matter per cubic metres of dry flue gas at standard temperatureand pressur62 Limit for particulate matter em.issions for bh,ssc burnjro pla,nts is i00 W/-i 3

3 Use corrected value @ 12% CO2 to compare with Emission Standards

/I/

4

-- -

1L3-Jfr-2005 11:14 62S2840 '94R p.r0s

AMBIENT AIR QUA"TY M¢EASUREDDATA-ocation Downwirid of st3-kDate From 12' tG o I't of cOctober 2003

Arbient Pollutant . Averaging 'Measured IEPA 2002 Measurement Method' Time Data (uglm3) 'Standard (ug!m3)

Parliculac Miatter <,O rnicrons _2 hours 200 | 100 -High Volume Sampler _

'7K- Dj,yi& ! 1 hour 2- 350 Fluorescence S02 anawyse,.

24 hours 09 200 Calorimetric-- j t- - V - --- ____

N Dioxide 1 24 hours I 87_1 200 IChemiluminescenca's techniquesi

Carbon Monoxide - | iour 2 250 25 000 Nondispersive Infrared

- hours 1 625 1000 Photometer

Ozone |1 hour i 64 100 |Chemitumirniescence's techniques|

xJ' 'J

1- -JN-2005 i : 14 . 26240 9P.06

TABLE 1. FACTORY DATA: SAVANNAH 2002 ;Fuel Bagasse _.- -

Boiler Type Pohn Thompson Dumping GradeScrubber:Type Decompression Chamber Wet ScrubberNumber of stacks OneStack Diameter 3.40 mStack Pressure range 3 mm H20Stack Velocity range 9.5 - 10.3 rn/sStack Flow Rate range 30 - 47 mnlsAverage Flue Gas Temperalure 68 - 70 OCFlue Gas Molecular Weight 32.34 (Cl2 scale)Flue Gas Moisture Content 19 % m/m

TABLE 2:' STACK GASEOUS EMISSIONS DATASource of sampling jPorts on chimneyDate I 12 - 23 August 2002Component Measured Concentration EPA 1991

Concentration @15 % 02 StandardOxygen, % 3.6 15 NoneCarbon Dioxide, % 15.8 5.4 NoneSulphur Dioxide, ppm 38 13 42Nitrogen Dioxide, ppm 43 15 374Carbon Monoxide, ppm 5870 2020 800NOTE:Use concentrations @ 15 % O° to compare with Emission Standards

TABLE 3: STACK PARTICULATE MATTER EMISSION DATA -Source of sampfing Ports on chimneyDate I 26 -28 August 2002Actual Particulate Matter Load ., mg/iM

3 2' _

Particulate.Matter Load @ 12% C02, mg/im3 198NOTES:1. * In- milligrams of particulate matter per cubic metres of dry flue gas at standard temperatureand pressure2Tuimiit forlparticulate matter emissions for bagasse buming plants iiA- Wm .3. Use corrected value @ 12% C02 to compare with Emission Standards

4

6262840 .% P. 07

-TABLU4: AMBIENTM1RQUALITYDATA' W .: - f7.! Date . NO., ppb S02,ppb 03, ppb CO, ppm PM10, pg/m 3

I23 August - 11 4 1 32 0.02 4424t August 12 13 1 31 0 03 4625t August 14 0 t 30 0.03 28

r 26 August 14 1 ] 32 0.06 41L 27thAugust-7 12 2 29 0.04 30I NOTE:

Tests performed approx. 40m downwind of stack

Akash GURA GOREDOProject Engineer1 3th November 2002

(1I4

13-JRFlN-20MS5 11:16 8 .9°F

~ZcLŽ \

TCH 134Boiler Type John Thompson Dumping Grade

Fuel BasaasseSteam Production 66 tons per hour

Electricity Production 9.8 MWScrubber Type Decompression Chamber Wet Scubber

Number of stacks OneDiameter of stack 3.4 mHeight of stack -30 mAverage stack pressure 5mm H20

Average flue gas temperature 67 oCFlue gas molecular weight 30.29Flue gas moisture content 20 % by weight

Source of sampling Ports on chimneylAate : 10 - 20 AUG 2001

Component Measured Concentration EPA 1991Concentration @15 % 02 Standard

Oxygen,% 6.14 15 None .1

Carbon Dioxide, % 14.29 5.79 None

Sulphur Dioxide, ppm 3.94 1.58 42

Nitrogen Dioxide, ppm 124 50 374

CarbonMonoxidelppm 3663 j----1470 -800 vp /

NOTE:use concentrations 15 % Oz to compare with Emission Standards

C:WItATEN MfL E{T NWNWWwSource of sampling Ports on chimneyDate 10 - 20 AUG 2001

Actual Particulate Matter Load 1255 mg/m3

Particulate Matter Load @ 12% C02 210 g/m3g rvt 4 6 Lf

NOTES:1. 'in milligrams of particulate matter per cubic mefres of ry flue gas at standard

temperature and pressure2. Limit for particulate matter emissions for bagasse buming plants is 4O0mgWm33. Use corrected value @ 12% C02

to compare with Emission Standards

Akash-GURA. GOREDOProject Engineer.22nd November 2001

I 3-JQfN-200S5 1 j: 17 6262b40 94- P .09

TCH 125Boiler Type John Thompson Dumping Grade

Fuel Bagasse

Steam Production 66 tons per hourElectricity Production 9 8 MWScrubber Type Decompression chamber wet scrubberNumber of stacks OneDiameter of stack 3.4 mHeight of stack 30mAverage stack velocity 9 rr/sAverage stack flowrate 80 ms/s

Average stack pressure 0.5 cm HzO

Average flue gas ternperature 70 -'C

Flue gas molecular weight 30.3Flue gas moisture content I 8% by weight

Source of sampling Fac1oy yard, approx. 150 m downwind

Date August 17th 2000 to August 27th 2000.

Pollutant 24-hour EPA 1991Average Standard

Particulate Matter < 10 microns 58 ug/ni 100 ugIm'

Sulphur Dioxide 3.5 ppb 70 ppb

Nitrogen Oxides 33 ppb 75 ppb

Carbon Monoxide Q05 ppm 8 ppm

Ozone J46 ppb 47 ppb

Source of sampling Ports On chimney

Date August 17n 2000

Measured Concentration EPA 1 99tCinponent Conrcentration @15 % 02 Standard

Oxygen 8.28% 15% None

Carborn Dioxide 12.25% 5.95% None

Carbon Monoxide 1000 ppm 470 ppm 800 ppmr

Sulphur Dioxide 4.2 ppm 2 ppm 42 ppm

Nitrogen Dioxide 121 ppm Ppmp 374 ppmn

A correction factor @1 5 % 02 is applicable to gaseous concentrations.Useconcentration @15 % 02 for comparison to environmental emission standards

Source of sampling 1iorts on chimney

Date and time of test Aug 21" 2000 1Actual Particulate matter load' 204 mgrn 3 l

Particulate matter load 1 12% CO, 200 mg/rnNote:l - in milligrams of particulate matter per cubic metres of dry fue gas at standard

temperature and pressure

2. Emission standard for particulate matter for bagasse burning plants is 400mg/in3

3. Use actual PM load for design of scrubber4. A correction factor @ 12 % C02 is applicable to particulate matterconcentrations.Use corrected value @ 12% CO2 for comparison to emission norms

13-JRThN-2005 11:18 6262840 95S P.10

- "a I.j. %-urottuwUtrt urtu /Jy.ctuWr uj UOJ.tfWi Jr ruwLer -uriw. rage b /

Stack and Emission Characteristics of Existing Sugar Factories and Power Stations

Pollutants Atmospheric Emission Rates at each Sugar Factorymg/Nm3 Kg/h

USA Savannah MT-MD USA Savannah MT-MD

PM 318 281 300 60.42 53.25 30.41

S02 17 13 5 3.23 2.46 0.51

NOx 205 15 55 38.95 2.85 5.58

Co 298 421 286 56.63 79.77 28.99

PCDD=

Furnace CharateristicsStack Height 30m 30m Om

Stack Diameter 3.65m 3.40m 2.17m

Stack Temperature 750C 800C 1750C

Stack Velocity 8.0m/s 7,5m/s 12.5m/s

Flux NM3/h 190 000 189 486 101 364

Crushing Rate 140TCH 140TCH 106TCH

Burning Rate 41.5TBH 41.3TBH 32.9TBH

The entries of Table call for the following remarks: 45

* The pollutant concentrations in mg/Nm3 have been communicated by the Proponent4.

* Inasmuch as S02 is concerned, the stoichiometric equation and a 0.01% to 0.015% S-content in

bagasse, would yield 200 mgSO2 to 300mgSO2/Kgbagasse. This is what has been proposed by

SIDEC for the bagasse-firing operation of CTSav, with a 10% retention of S02 in the ashes

captured by the ESP.

In the case of CTBV at Belle-Vue, the following maximum emission factors, from AP-42

Regulations (USA), have been proposed for the various pollutants expected from bagasse.

POLLUTANT EMISSIONFACTORSMass/BTU Mass/GJ Mass/kg Bagasse

PM 0.130 kg PM/GJ I 000 mg PM/kgB

NOx 0.181 lb NOx/1 06 BTU 600 mg NOx/ kgB

CO 0.351bCO/106BTU 0.150kgCO/GJ 1 165 mgCO/kgB

VOC 0.061b VOC/10 6 BTU 0.0258 kg VOC/GJ 200 mg VOC/kgB

Pb 8x10-3 mg Pb/kgB

HCI 5.6x10-41b HCL/106 BTU 2.404x10- 4 kg HCI/GJ 1.86 mg HCI/kgB

FluoridesCO2

780 gm CO,/kgB

Notes:

(1) Uncontrolled NOx emission values, sampled downstream of the PM control systems,

according to AP-42 (April 1993) are quoted to range between 0.12 and 0.43 gm/kg steam raised in

the bagasse-fired furnace. Conversion factors used in AP-42 are, for information, 21b steam/lb

bagasse, and 3 50OBTU/lb wet bagasse.

45 E-mail message from M Guy MAUREL 07 VI 2005.

EIA - CTDS: Construction and Operation of a 83. 0MWI' Power Plant rage aa

Per ullit weight of combustible, therefore, the NOx emission factors are between 240 and 860 mg

NOx/kg bagasse. The average figure of 600 mg NOx/kg bagasse is adopted.

(ii) VOC emissions are primarily clharacterized by the criteria pollutant class of unburned

vapour phase hydrocarbons. Unburned hydrocarbon emissions can include essentially all vapour

phase organic compounds emitted from a combustion source. These are primarily emissions of

aliphatic, oxygenated, and low molecular weight aromatic compounds which exist in the vapour

phase at flue gas temperatures. They are not sampled and analysed in Mauritius. They do not

include PCDD and PCDF.

Pollutants Atmospheric Emission Rates at each Sugar Factory

mg/Nm3 Kg/h

USA Savannah MT-MID USA Savannah MT-MD

PM 318 318 173 41.50 41.30 32.90

S02 66 65.7 97 12.453 12.45 9.87

NOx 131 131 55 24.90 24.90 19.74

CO 257 257 195 48.90 48.9 30.92

VOC 43.7 43.7 65 8.3 8.3 6.6

Pb 0.00175 0.00175 0.003 3.32 x 1 0 -4 3.32 x 10-4 2.63 x 10-4

HCI 0.405 0.405 0.602 0.077 0.077 0.061

CO2 170 368 170 368 255 712 32 370 32 370 25 920

PCDD/PCDF 0.10xlO-6 0.1Ox10 6 0.10xlO-6

Furna ce Charateristics

Stack Height 30m 30m Om

Stack Diameter 3.65m 3.40m 2.17m

Stack Temperature 750C 800C 1750C

Stack Velocity 8.0m/s 7,5m/s 12.5m/s

Flux Nm3/h 190 000 189 486 101364

Crushing Rate 140TCH 140TCH I106TCH

Burning Rate 41.5TBH 41.3TBH 32.9TBH

COMPAGNIE THERMIQUE de SAVANNAH LtCe ......COMPAGNIE THERMIQUE de SAVANNAH LtCe CONSTRUCTION &...

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