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WEST BENGAL STATE ELECTRICITY DISTRIBUTION COMAPANY LIMITED

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CONTENTS

Contents i

Bandu Pumped Storage Project,

(4 x 225 MW)

Pre-Feasibility Report

TABLE OF CONTENTS

CHAPTER NO.

SUB-HEADING DESCRIPTION

Page No.

1 EXECUTIVE SUMMARY

1.1 Preamble 1

1.2 Project Background 1

1.3 Project Location 2

1.4 Access to the Project 3

1.5 Scope of Works 3

1.6 Topography & General Climate 4

1.7 Hydrology 4

1.8 Geology 5

1.9 Installed Capacity and Power Generation 6

1.10 Power Evacuation Arrangement 6

1.11 Environmental Aspects 6

1.12 Estimates of the Cost 6

1.13 Financial Aspects 7

1.14 Conclusion & Recommendation 8

Salient Features 9

2 HYDROLOGY

4.1 Introduction 1

4.2 Rainfall 1

4.3 Evaporation 1

4.4 Sedimentation 2

4.5 Water Availability 2

4.6 Design flood 3

4.7 Irrigation demand 3

4.8 Conclusions and Recommendations 4

3 GEOLOGICAL STUDIES

5.1 Introduction 1

5.2 Accessibility 2

5.3 Regional Geology 2

5.4 Geology & Geomorphology of Ajodhya Plateau

Area 4

5.5 Seismo- Tectonics and Seismicity of Bandu

Pumped Storage Project 5

5.6 Geology of the Project Area 7

5.7 Conclusions: 12

4 PROJECT PLANNING AND INSTALLED CAPACITY

6.1 Previous Studies and Documentation 1

6.2 Project Planning 1

6.3 Installed Capacity 5

Contents ii


(4 x 225 MW)


CHAPTER NO.


Page No.

5 PLANNING & DESIGN OF CIVIL STRUCTURES

7.1 The Scheme 1

7.2 River Diversion 1

7.3 Selection of Layout - General 1

7.4 Underground Power House & Underground

Transformer Hall 10

6 ELECTRO-MECHANICAL EQUIPMENTS

8.1 General 1

8.2 Power evacuation arrangement 4

8.3 Sources for Control and Indication lamp 4

8.4 AC Electrical auxiliaries supply system 4

8.5 Brief Particulars of Pump-Turbine Equipment 5

8.6 Brief Particulars of Generator-Motor Equipment 10

8.7 Power Transformer 11

8.8 Generator-Motor Main circuit 12

8.9 High Voltage Power Cable (400 kV XLPE

Cable) 12

8.10 Switchyard 400Kv 12

8.11 Station Service Circuit 13

8.12 Control and Protection System 13

8.13 Emergency Power Supply System 14

8.14 EOT Crane 14

8.15 Fire extinguishing System 15

8.16 Grounding System & LAVT System 15

8.17 PLCC Equipment 16

8.18 Communication system & surveillance system 16

8.19 Air conditioning & Ventilation system 16

8.20 Illumination System 16

8.21 Power, Control Cable & Instrumentation cables

and cable trays etc. 17

8.22 Draft Tube Gates 17

8.23 Firefighting System 17

8.24 Electrical Equipment Testing Laboratory 17

8.25 Mechanical Workshop 17

8.26 Lift 18

8.27 Oil handling system 18

8.28 Back to Back Starting Method 18

8.29 DC supply System 18

8.30 Advantage and disadvantage of variable speed

machine 18

7 COST ESTIMATE

10.1 Project Cost 1

Contents iii


(4 x 225 MW)


CHAPTER NO.


Page No.

10.2 Basis of Estimate 1

10.3 Classification of Civil Works Into Minor

Head/Sub Heads 2

10.4 Direct Charges 2

10.5 II-Establishment 5

10.6 IV-Receipt & Recoveries 6

10.7 Indirect Charges 6

10.8 Electro-Mechanical Works 6

8 ENVIRONMENTAL & ECOLOGICAL ASPECTS

11.1 Need for the Study 1

11.2 Study Area 1

11.3 Environmental Baseline Status 1

11.4 Prediction of Impacts 17

11.5 Environmental Management Plan 39

11.6 Infrastructure Development Under Local Area Development Committee (Ladc)

58

11.7 Environmental Monitoring Programme 58

11.8 Cost for Implementing Environmental Management Plan

60

9 CONSTRUCTION MATERIAL

12.1 General 1

12.2 Estimated Quantities of Construction Materials 1

12.3 Geo-technical Investigations in vicinity 2

12.4 Construction Materials (Rockfill /Coarse and

Fine aggregates) 3

12.5 Conclusions 7

10 ECONOMIC EVALUATION

13.1 General 1

13.2 Project Benefits 1

13.3 Capital Cost 1

13.4 Mode of Financing 2

13.5 Phasing of Expenditure 2

13.6 Financial Analysis 3

11 POWER EVACUATION ARRANGEMENT

14.1 Introduction 1

14.2 Existing Power Scenario of West Bengal 1

14.3 Power Evacuation Arrangement 1

CHAPTER – 1

EXECUTIVE SUMMARY

Chapter -1 : Executive Summary 1

Bandu Pumped Storage Project, (4 x 225 MW)


Chapter - 1

Executive Summary

1.1. Preamble

WBSEDCL initially envisaged construction of four Pumped Storage Schemes in the Ajodhya Hills in 1978 and accordingly GSI evaluated the geotechnical feasibility of the four Pumped Storage schemes in the Ajodhya Hills during FS 1978-1979 on Bandu Nala, Turga Nala, Kistobazar Nala and Kathlajol Nala (Gangopadhyay, 1979). Out of these four projects, Purulia Pumped Storage Project (PPSP) on Kistobazar Nala has already been constructed and commissioned in 2007-2008 with an installed capacity of 900 MW. Thereafter, a Detailed Project Report (DPR) of Turga Pumped Storage Project (Turga PSP) of 1000 MW has been prepared during 2012-16 and presently (2017-18) is in pre-construction stage investigation with an aim to undertake the construction from 2018 onwards. A Pre-Feasibility report (PFR) of Bandu Nala was prepared by WBSEDCL in the year 2013. Now, WBSEDCL has entrusted WAPCOS to update this PFR according to the latest data and possible optimisation in the layout. The project area is located in the north-eastern fringe of the Ajodhya Hills near Ayodhya village in the Purulia District, West Bengal. Bandu PSP envisages construction of a rockfill dam across Bandu Nala and a saddle rockfill dam at higher reaches, a rockfill dam across Bandu Nala at lower reaches, an Underground Power House (UGPH) in between to generate 900MW peaking power. The Upper Rockfill Dam is proposed across Bandu Nala near village Ayodhya. The Bandu Project area covering three dams including upper saddle dam & two reservoirs, underground power house (UGPH) and water conductor system.

1.2. Project Background

The state of West Bengal has unique feature with Himalayas in the North and the Bay of Bengal in the South, offering huge Hydro Electric potential. The Hydro Power development in West Bengal is, however, not spectacular. The total installed capacity is about 1417 MW as against a potential of 1786 MW of conventional Hydro Power and about 4800 MW of Pumped Storage Hydro Power. The Power scenario in the state is now adversely placed with a Hydro: Thermal mix nearly 13.89:86.11 (January 2018) as against a minimum desired ratio of 40:60. The Survey and Investigation circle of West Bengal State Electricity Board now renamed as West Bengal State Electricity Distribution Company Limited (WBSEDCL), has investigated a number of hydro electric project through their offices at Kurseong since 1967 and at Siliguri since 1988. Project like Jaldhaka hydro-electric projects stage-I and stage-II with an installation capacity of 45MW(4x9+2x4), Rammam Hydro Electric Project Stage-II with 51MW(4x12.75), Teesta Canal Fall Hydro Electric




projects with 67.50MW(3x3x7.50) and Mongpoo Kalikhola Hydel Project with 3MW(3x1) are all run -of -the-river Projects planned and completed by the Hydro wing of WBSEDCL. In spite of that, potentials were also identified by the Survey and Investigation wing of WBSEDCL for development of Pumped Storage Project in south Bengal. The Central Electricity Authority (CEA) in 1979 identified a possible site of Pumped Storage Project on Bandu Nala in Ayodhya hills under district Purulia, West Bengal. Subsequently, the investigations were made by the Engineers of Survey and Investigation Wing of West Bengal State Electricity Board, now WBSEDCL and identified another three more Pumped Storage Project in the same hills. A preliminary study of the schemes shows that all the above schemes are techno- commercially feasible. The other three schemes were:

i ) Kistobazar nala Pumped Storage Scheme ( 900 MW ) ii) Turga nala Pumped Storage Scheme ( 600 MW ) iii) Kathlajal nala Pumped Storage Scheme ( 900 MW )

Out of the above four schemes, the Kistobazar nala Pumped Storage Scheme, renamed as Purulia Pumped storage Scheme was got the first priority and the project was taken up for execution by the West Bengal State Electricity Board (now West Bengal State Electricity Distribution Company Limited) with the financial assistance of JICA (earlier OECF and JBIC), Japan. The project was completed in 2008 and now under commercial operation. The Turga Pumped Storage Scheme is the second Pumped Storage Scheme being taken-up by WBSEDCL after the Purulia Pumped Storage Project. The capacity of Turga Pumped Storage Scheme after completion of PFR stage studies, has been revised to 1000 MW in 2012 and the Detailed Project Report (DPR) preparation activities were also taken up by engaging the Local Consultant, WAPCOS in association with CEA & CWC and the Foreign Consultant, EPDC (J-Power) – Japan and completed. The implementation of the project is now in progress.

1.3. Project Location

The proposed Bandu Pumped Storage Project is located near Ayodhya village in Purulia district of West Bengal, India (Figure 1). The Bandu Project areas come within the confines of Ayodhya hills which is a part of Chotonagpur Plateau. The altitude of the project area varies between 300m and 600 m. The scheme is located in between Latitude 23o 14’ 17.237” North and 23o 13’ 57.734” North; Longitude 86o 10’ 15.95” East and 86o 09’ 22.7585” East. Reference Topo-sheet for the project is No.73I/4/ NE (Everest/Polyconic) or F45C/4/NE (UTM/WGS84) of Survey of India.It is situated in the Purulia District of the State of West Bengal. The tail pool dam site is very near to village Sirkabad and accessible with motor able road. The upper dam site can also be approached by the Sirkabad-Ayodhya road. Some improvement of the road will enable




the sites to be connected by truck able road. For power house approach tunnel, a new road is to be developed.

Figure 1: Location Map

1.4. Access to the Project

Ayodhya village is about 40km from Bagmundi village which is connected through an all-weather metalled road (58 km via NH-32 & SH-4) with Purulia town, Headquarters of the Purulia District, which is further connected both by rail and road with Kolkata (about 250 km). The nearest airport is Ranchi in Jharkhand which is located 112 km west of Baghmundi and can be approached through highways SH-2 & SH-4.

1.5. Scope of Works

The project will be a Close Loop type Pumped Storage Scheme. It will comprise two reservoirs: one at lower elevation and other at upper elevation. The difference of water levels of the reservoirs will represent the effective “head” of the Project. The water conductor system will connect the two reservoir through an underground power house. The Scheme envisages construction of:




A 71 metre high Rockfill upper dam with central impervious clay core across river Bandu to provide a live storage of 13.49 million cum with Full Reservoir Level at 480.00 metre and Minimum draw down Level at 460.83 metre. Poundage for 1 MCM Irrigation requirement is also proposed in Upper Reservoir. The MDDL for Irrigation depletion is EL 458.75m.

A 53 metre high Rockfill lower dam with central impervious clay core across river Bandu to provide a live storage of 13.49 million cum with Full Reservoir Level at 340.44 metre and Minimum Draw down Level at 325.00 metre.

An underground power house with four numbers Francis type reversible pump-turbine of capacity 225/255 MW.

An underground Transformer cavern with four numbers Power Transformer of capacity 280 MVA.

One 400 kV Gas insulated Switchgear. 1687 metre long headrace and tailrace tunnel for conveyance of water.

1.6. Topography & General Climate

The Bandu Nala a tributary of Kangsavati river, originates from the Ajodhya Plateau near Ayodhya village and flows towards NE along a meandering course upto the confluence of Karachipa Nala and Marangara Nala (Rajabandh Nala) and thereafter it comes down to peneplain and flows northerly for a considerable distance and abruptly turns towards east at the south of Jhalda town of Purulia district to meet Kangsabati River near Purulia town. A number of tributaries meet the Bandu nala from both the banks forming parallel drainage system. However, the major tributaries like Karachipa Nala and Marangara Nala (Rajabandh Nala) are meeting the trunk stream at the downstream of the project site. The climate of the region is characterized by hot summer followed by the south west monsoon from middle of June to September and retreating monsoon from October to November. Cold weather starts from middle of November and lasts till end of February. The mean daily maximum and minimum temperature of the region is 25.3°C and 12.4°C, respectively. Baghmundi is the nearest rain gauge station where the average annual rainfall is 1334 mm. Non monsoon rainfall is scarce and varies from 5 to 15 % of the monsoon rainfall.

1.7. Hydrology

The Bandu nala carries only seasonal flow of water during and immediately after the rains. During the monsoon it becomes a torrent and water level rises within a few hours after heavy rains. The course of the river flows between sharply defined banks formed chiefly of stone outcrops. The nala mainly carries seasonal flow of water and immediately after the rains, the rivulets dries almost. The Bandu nala drains a catchment area of about 24.00 sq. km at the proposed lower dam site and 3.50 sq. Km




at upper dam site. The Rainfall-runoff correlation of Purulia Pumped Storage Project has been considered primarily for the catchment. The design flood has been assessed as 600.00 comics for lower dam and 130 cumecs for upper dam. The sediment rate of 950 m3/km2/year has been considered.

1.8. Geology

The Project is located in Ajodhya Hills between South Purulia Shear zone (SPSZ) and North Purulia Shear Zone (NPSZ), and has undergone three phases of tectonic deformations (Das, 1991). The Phase-I deformation has North-South principal compressive direction developing the isoclinal fold (F1) with E-W sub-horizontal axis and overturning towards south responsible for the development of S1 axial plane schistosity. The Phase-II deformation has N-S to NE-SW compressive stress developing isoclinal, reclined to asymmetric inclined folds (F2) with easterly and westerly plunging axis responsible for the development of dominant S2 - crenulation/fracture cleavage. The Phase–III deformation reflects East-West compression resulting development of gentle to open cross folds (F3) with northerly plunging axis formed by folding of S2 foliation plane. In the project domain the trend of prominent foliation swings from E-W to NW-SE with low to moderate dips towards N and NE. The rock types in the project domain are dominantly hard compact quartzo-feldspathic gneisses and its petrological/petrographical variants with subordinate meta-basic rocks (e.g., amphibolite gneiss).Three major litho-types of gneisses are: (i) augen gneiss with minor pegmatites, (ii) quartzo-feldspathic gneiss with minor mica- gneiss and (iii) quartz-biotite gneiss. The gneiss at many places show migmatitic structure with relict bands of amphibolite & schists, pegmatite veins and ptygmatic quartz veins. The Ajodhya Hills forms a NW-SE trending plateau. The drainage system in the area is mostly structurally controlled with valleys along NNW-SSE, E-W& NNE-SSW trending lineaments/shear zones (Nag S.K. and Chakraborty, S. 2002; Archarya,T. and Basu Mallik, S. 2012). The Plateau is characterized by an extensive planation surface (EL660m). The plateau slopes steeply towards south and south west and forms flat low level plain (EL < 400m) at the foothills. The major drainages originating from the Ayodhya plateau show a radial pattern all along the periphery of the plateau. The major nalas are generally structurally controlled by lineaments/master joints. However the tributaries meeting the major nalas from both the banks are generally structurally controlled by mainly master joints reflecting parallel drainage pattern. Within the hilly segment, this stream appears to follow a lineament. This conspicuous lineament has been inferred to be shear zone/fault within granite gneisses on the basis of photo signatures (Chakraborty, 1988).

1.9. Installed Capacity and Power Generation




The factors that influence the installed capacity of pumped storage scheme at a site are the requirement of daily peaking hours of operation, operating head, live pondage in the reservoirs and their area capacity characteristics. The details are summarized below:

Installed Capacity (MW) 900 No of units 4 Unit Size (MW) 225 Head (max) 155 Head (Min) 120.39 Hours of Peaking Operation 5 Annual Energy Generation (GWh) 1642.5 Annual Pumping Energy (GWh) 2135.25 Cycle Efficiency 76.92 %

1.10. Power Evacuation Arrangement

The 900 MW power generated from the project at 16.5 kV will be stepped up to 400kV. This power will thereafter be evacuated from Pothead yard area through one Double Circuit 400 kV Quad Moose/Twin HTLS Transmission lines to New Purulia Pumped Storage Project 400 kV GIS which is about 15 km and one Double Circuit 400 kV Quad Moose/Twin HTLS Transmission lines to Turga PSP 400 kV GIS. 1.10.1 Environmental Aspects The submergence area of the project is 198 ha comprising forest. The total land requirement for the construction of various components including construction facilities will be about 397 ha. On the basis of preliminary assessment on environmental issues, the project is likely to entail certain adverse environmental impacts. However, these can be ameliorated to a large extent by implementing appropriate mitigatory measures. A detailed study on the environmental issues that may arises due to construction and operation of the proposed project will be taken up so that appropriate management measures can be taken up and be delineated as a part of Environmental Management Plan (EMP), which will be covered as a part of the Comprehensive EIA study.

1.11. Estimates of the Cost

The breakup of the cost estimates for option-I and Option-II is given below at December, 2017 price levels: Option: I - Considered all 4 machines are Fixed Speed Machines

Option: II- Considered 2 (Two) machines are Variable Speed machines + 2 (Two)

machines are Fixed Speed Machines




Item Estimated Cost (Rs. In Crore)

Option: I Option: II

Civil Works 2032.11 2036.93

Electro-mechanical Works 1687.77 2041.89

Transmission line 90.00 90.00

Total 3809.88 4168.82

Power evacuation cost considered

1.12. Financial Aspects

The estimated cost of the Bandu nala Pumped Storage Scheme for option-I and Option-II is Rs. 3809.88 Crore and 4168.82 Crore respectively and the annual energy generation will be of 1642.5 GWh. The project is scheduled to be completed by a period of 5 years 3months. Based upon the parameters given above, the sale rate of energy at bus bar has been computed in Annexure. The sale rate applicable in the first year and levellised tariff is indicated below. (Land cost is included)

i) Option-I (4 Fixed Units)

Sl. No. Off Peak Energy Rate (Rs/kWh)

First Tariff (Rs/kWh)

Levelized Tariff (Rs/kWh)

1 1 7.54 6.86 2 2 8.89 8.20 3 3 10.23 9.55

ii) Option-II (2-Fixed and 2-Variable Unit)




1 1 8.11 7.36 2 2 9.45 8.70 3 3 10.79 10.05

1.13. Conclusion & Recommendation

In the updated Pre-Feasibility Report inter-alia following modifications have been prepared.

1. The location of Upper Dam has been shifted from the earlier location by 1635m.




2. The length of the water conductor system has been reduced symmetrically about 1878m from the earlier PFR. The above modifications have made the scheme more economical and technically better for further studies.




Salient features

Country India State West Bengal District Purulia River Bandu Nala a tributary of Kasai River Upper Dam site Latitude 23˚ 13’ 57.734”

Longitude 86˚ 09’ 22.758” Lower Dam site Latitude 23˚ 14’ 17.237”

Longitude 86˚ 10’ 15.95” Access to the Project Kolkata to Purulia along NH 2 via

Durgapur, Bankura and Purulia. Purulia to Sirkabad along a State Highway and Sirkabad to Project site along village Road - (340 Km) Kolkata to Chandil along NH33 via Jamshedpur. Chandil to Balarampur along NH 32 and Balarampur to Pathardih along a State Highway. Pathardih to Project site along Purulia Project Road and village Road - (465 Km)

Airport Kolkata (International) and Ranchi (Domestic)

Railhead (with unloading facilities) nearest rail head is Tumna on Howrah Purulia Broad Gauge Line of South Eastern Railway. But for loading and unloading facilities, Purulia Railway Station (28 km from Project site ) on Howrah Purulia Broad Gauge Line of South Eastern Railway ( 323 Km from Howrah via Bankura and 431 Km from Howrah via Tatanagar- Chandil)

Port Kolkata (handling capacity 200MT) and Haldia (handling capacity 50 MT)

Project: Type Pumped Storage Hydro-Electric Power 900 MW Installed Capacity 4x 225 MW Peak operating duration 5 hours

Hydrology




Catchment area 27.50 Sq.Km Upper Dam 3.50 Sq Km Lower Dam 24.00 Sq Km Average rainfall 1400 mm Maximum Design Flood for Upper Reservoir 600 m3/Sec Maximum Design Flood for Lower Reservoir 130 m3/Sec Annual Average sediment load 950m3 /Km2//year

Civil Structure Upper Reservoir MWL 482.00 m FRL 480.00 m MDDL (Generation) 460.83 m MDDL (Irrigation) 458.75 m2 Reservoir surface area at FRL 0.96 Sq. Km Reservoir surface area at MDDL 0.52 Sq. Km Gross capacity at MWL 21.83 Million m3 Live storage 13.49 Million m3

Dead Storage at 460.83 m 8.34 Million m3 Irrigation Storage 1.00 Million m3

Upper Dam Type Rockfill with central impervious core River bed level 414 m Top of dam 485 m Maximum height 71m Top width of dam 10.00 m Length of the dam at crest 1776.00m

Lower Reservoir MWL 343.00 m FRL 340.44 m MDDL 325.00 m Reservoir surface area at FRL 1.019 Sq. Km Reservoir surface area at MDDL 0.744 Sq. Km Gross capacity at FRL 25.19 Million m3 Live storage 13.49 Million m3

Dead Storage 11.70 Million m3

Lower Dam Type Rockfill with central impervious core River bed level 293.00 m Top of dam 346.00 m Maximum height 53 m




Top width of dam 10.00 m Length of the dam 644.00m Upper Dam Spillway Type Overflow Ogee type Gateless free flow Elevation of the crest 480 m Design Flood 130 Cumec Bays 2 Nos, 11 m(w) X 2 m(H) each

Lower Dam Spillway Type Overflow Ogee type Gateless free flow Elevation of the crest 340.44 m Design Flood 600 Cumec Bays 7 Nos, 15 m(w) X 2 m(H) each

Upper Saddle Dam Type Rockfill with central impervious core Top of Dam 485.00 m2 River Bed Elevation 460.00 m Length of Dam at top 172.00 m Maximum Reight 25.00 m

Power Intake Type Horizontal type with anti-vortex louver H x W x No. x Line 12.0 m x 14.0 m x 3 nos. x 2 lines Location Left Bank Number of Line Two Rated Discharge Capacity 370.50 Cumec Dia. Of Tunnel 8.3 m (Steel Lined)

Headrace Tunnel (Steel Lined) cum Pressure shaft Type Circular - Steel lining and embedded Location Left Bank Inclination Inclined and Horizontal Dia. of Tunnel 8.30 m x 847m x 2 lines Dia. of Tunnel after Bifurcation 5.90 m x 112m x 4 lines

Unit Tailrace Tunnel (Steel Lined) / Draft Tube Type Circular Dia. of Tunnel 7.00 m x 100m x 4 lines Tailrace Tunnel (Concrete Lined)




Type Circular Inclination Inclined and Horizontal Dia. of Tunnel 9.80 m x 628 x 2 lines

Outlet Structure Type Horizontal type with anti-vortex louver H x W x No. x Line 12.10 m x 13.90 m x 3 nos. x 2 lines Location Left Bank Number of Line Two Rated Discharge Capacity 370.50 Cumec Dia. Of Tunnel 9.8 m (Steel Lined)

Underground Power House Complex Type Underground Bullet shape Size 160m x Width 22.5 m × Height 48.00 m Transformer Room Type Underground Bullet shape Size 134 m x Width 18.00 m × Height 18m Switch Yard Type Open Air Type Length x Width 200 m x 50 m Main Access Tunnel Type D- shape (Length-975m) Width x Height 8.00 m x 8.50 m

Electro-Mechanical Equipment Pump Turbine Type of Turbine Francis type, vertical shaft reversible

Pump turbine Number of unit Four (4) units Installed Capacity (MW) 900 MW (4x225 MW) Generation period 5 hours Maximum Head 155 m Minimum Head 120.39 m Rated head 137.695 m Rated output at rated head 225 MW Specific speed 195.69 m-kW Rated speed 187.5 rpm Max. Turbine discharge 187.36 cumec at normal net head




Generator –Motor Type Three (3) phase, alternating current

synchronous, generator-motor, vertical shaft, rotating field, enclosed housing, rim-duct air-cooled and suspended type

Number of unit Four (4) units Rated capacity 250 MVA Power factor 0.9 lagging Rated terminal voltage between phases 16.5 kV+ 10 % Frequency 50 Hz Rated speed 187.5 rpm Over Load Capacity 110% rated capacity

Main Power Transformer Type Indoor, oil-immersed, 3 single phase

Transformers with on-load tap changer (OLTC) for pumping operation, OFWF cooled

Number 4 (four) sets Rated capacity 280 MVA Rated voltage Primary 16.5 kV, Secondary: 400kV+5%

Generator – Motor Circuit Breaker Type Indoor, Metal-enclosed, SF6 and single

Pressure type Number of Unit Four (4) units Rated Voltage 16.5 kV Rated Normal Current 12,000 A Phase Reversal Equipment Three Phase, 24kV, 12000 A

Gas Insulated Switchgear Circuit Breaker Type 400 kV Gas Insulated Switchgear (GIS) Number of Feeder Eleven (11) feeders Rated Voltage 420 kV Rated Normal Current 2,000 A Rated Short Time (1sec) withstand Current 50 kA

400 kV XLPE Cable Type Single Core 400 kV Cross linked

polyethylene Insulated type Rated Voltage 400 kV Number of Circuits 12 nos. + 1 spare single phase




Starting Method Type 1 no. Static Frequency Converter Starting

(SFC) & also Back to back starting (BTB) Capacity of Starting Transformer 2 nos.,16.5/ 7.5 kV,22.2 MVA and

7.2/16.5 kV,21.3 MVA Diesel Engine Generator Number of Unit Two (2) units Rated Capacity 2 x 1,000 kVA, 11 kV

EOT Crane Type Indoor, Electric Overhead Traveling Crane Number of Unit Two (2) units Rated Capacity 280 ton (Main hoist), 50 ton and 10 ton Span 21.50 m

Pothead Yard Number of bays 4 (Generator) + 1 (Bus Tie) + 3 x2 (Outgoing feeders) Outgoing feeders Type Double Circuit 400 kV Quad Moose/Twin

HTLS Transmission lines conductor Capacity Voltage Level 400 kV Length About 238 Km (18 Km + 25 Km +195 Km)

Project Cost (Price Level December 2017)

Item Estimated Cost (Rs. In crores)

Option: I Option: II

Civil Works 2032.11 2036.93

Electro-mechanical Works 1687.77 2041.89

Transmission line 90.00 90.00

IDC 461.42 487.12

Total 4271.30 4655.94




Project Benefit's





1 1 7.54 6.86 2 2 8.89 8.20 3 3 10.23 9.55





1 1 8.11 7.36 2 2 9.45 8.70 3 3 10.79 10.05

HYDROLOGY

CHAPTER- 2

Chapter – 4: Hydrology 1


(4 x 225 MW)


4.1 Introduction:

The Bandu nala originates at an elevation of 590 meter in the district of Purulia

in the state of West Bengal. The nala flows radially towards alluvial plains and

there after falls in River Kasai which is a tributary of Subarnarekha river. The

catchment area of the nalla is separated by an E-W trending water divide. The

basin is characterized of hilly topography of Ajodhya hills which undulates from

EL 500 m to EL 600 m with relatively dense vegetation in the upper reaches,

and faces a vast plain at El 270 m to 300m in the lower reaches. The nala

follows in a straight course for a length of about four kilometers from its origin

before taking a northerly bend to debouche into alluvial plains. The drainage

pattern of the area appears to be controlled by geological structures forming

rectangular and dendritic pattern. The lower dam site is located near the village

Rajabandh. The upper dam site is located near village Lohadungri and is

approachable by the Sirkabad –Ayodhya road.

4.2 Rainfall :

The Bandu nala carries only seasonal flow of water during rains and dries up

during non-monsoon period. During the monsoon it becomes a torrent nala and

water level rises within a few hours after heavy rains. The course of the river

flows between sharply defined banks formed chiefly of stone outcrops. During

non-monsoon period, it dries up and reduces to bed of sand and pebbles. No

rain gauge station exists in the catchment area of Bandu nala. The rainfall data

is available at Bagmundi area nearby where the Purulia Pumped Storage

Project was constructed. The hydro-meteorological data thus collected for

Purulia Pumped Storage Project may not be truly representative for the

catchment of Bandu nala but for the present purposes the same is utilized in

absence of site specific data. Utilization of available secondary data as well as

primary data available in the region including site specific data would be

considered during DPR stage. The normal annual rainfall over the basin varies

between 1200 to 1600 mm which mainly occurs during the monsoon months of

June to October. Non-monsoon rainfall is scarce and is only about 5 to 15% of

the monsoon rainfall.

4.3 Evaporation:

No data on evaporation is available for the catchments area. However, the data

is available for Purulia pumped Storage Project which is adjacent to the present

CHAPTER – 2

Hydrology



(4 x 225 MW)


scheme. The evaporation losses taken into consideration for Purulia Pumped

Storage Project may be adopted for the Bandu scheme as the same is adjacent

to the present scheme.

Month Loses in mm/day

January 2.26

February 2.86

March 4.52

April 6.00

May 6.77

June 5.67

July 3.55

August 3.87

September 3.33

October 2.90

November 2.33

December 1.61

4.4 Sedimentation:

No silt data is available for the river Bandu at the present dams location. The

data assessed and approved by the Central Water Commission, Ministry of

Water Resources, and Government of India for the Purulia Pumped Storage

Project has been considered for the present assessment. The silt rate

considered for Purulia Pumped Storage Project is 950 m3/Km2/year. The Dead

storage level/MDDL considered for the proposed Pump Storage scheme is 325

m while the bed level for Lower dam is 293 m which intercepts an area of 24

sq.km.

4.5 Water Availability:

It is reiterated that no raingauge station exists in the catchment of the proposed

Pump storage scheme. Recently the discharge observations at project site

have been started by project authorities. However length of data is too small.

Due to limited available site specific hydrological data, the yield calculations

have been carried out based on the secondary data as available in the adjacent

site of Purulia PSP site. Thus installation of rain gauge stations in the

catchments and discharge measurement by constructing the gauge sites at

upper dam location and lower dam location in subsequent stages is necessary

and is recommended.

To assess the flows at proposed project site, the yield series developed for the

Purulia Project have been considered for the period 1950-1989 (Ref: Turga

PSP DPR Vol. IV Hydrological Studies, Oct.2016). The same has been

transposed in the catchment area proportion of Purulia lower dam to yield



(4 x 225 MW)


runoff series at proposed both Upper and Lower dam site of Bandu Nala PSP

tentatively. The same would be reviewed/modified at DPR stage considering

the other relevant and site specific data. The yield series is at Annexure- 1A &

1B

4.6 Design flood:

The criteria for fixing spillway capacity of storage dam is as per IS 11223-1985

“Guideline for fixing Spillway Capacity”. According to this guideline, different

inflow design floods to be considered for different requirement are for safety of

the dam, efficient operation of energy dissipation system, extent of upstream

submergence and downstream damages in the valley. The lower dam and

upper dam which intercepts an area of 24.0 km2 and 3.5 km2 have Gross

storage capacity of 25.772 MCM and 20.088 MCM respectively.

Since the size of the catchments are less than 25 sq. km, and the hydro-

meteorological data is also not readily available for the Bandu Nala Pumped

Storage Scheme, the design flood study carried out for Purulia Pumped

Storage Project have been considered for estimation of design flood for the

lower dam and upper dam of Bandu Nala Pumped Storage Scheme. The

design flood has been estimated for lower and upper dams of the scheme

based on catchments area proportion to the power ¾ and would be modified

during DPR stage.

The values estimated by this method are:

Type of flood

Unit= m3/sec

Lower Dam

C.A. 24.00 Sq

Km

Upper Dam

C.A. 3.5 Sq Km

100 Years 223.72 Cumec 47.61 Cumec

Standard Project Flood (SPF) 467.50 Cumec 99.61 Cumec

Probable Maximum Flood (PMF) 599.35 Cumec 127.71 Cumec

Installation of self recording gauge in the catchments for self-recording rainfall

and gauge data are necessary for observing the fluctuation in the discharge

data.

4.7 Irrigation demand:

The water of the Bandu nala at lower dam location is being utilized for irrigation

purposes but no irrigation structures exists there. Water is drawn directly from

canal for irrigation purposes. During DPR stage enough provisions shall be

made to provide irrigation downstream with reliability.



(4 x 225 MW)


4.8 Conclusions and Recommendations:

No raingauge station is available in the catchment area of proposed project.

The runoff data being collected/started recently needs to be carried out based

on BIS standards. No silt data is available in the region. As such, it is

suggested to immediately establish a hydro-meteorological station at proposed

project site, so that site specific data including silt data are collected which

could be considered during DPR stage.

In the present assessment, the design flood for upper dam and lower dam have

been estimated by empirical approaches and as such needs to be carried out

based on hydro-meteorological approach at DPR stage. For this, installation of

self recording gauges for continuous record during monsoon period is required.

Keeping in view of static head criteria, and non availability of continuous

discharge in the catchment, the assessed probable maximum flood (PMF) for

lower dam 600 m3/sec and for the Upper dam 130 m3/sec have been

considered tentatively.



Annexure-1A

Yield Series at Bandu PSP Upper Dam site C.A= 3.5 Sq.Km Unit = MCM

YEAR JUN JUL AUG SEPT OCT MONSOON NON-

MONSOON ANNUAL

1950 1.47 0.54 0.75 0.46 0.15 3.37 0.44 3.81

1951 0.19 0.59 0.29 0.49 0.18 1.74 0.23 1.96

1952 0.17 0.53 1.12 0.55 0.29 2.66 0.35 3.00

1953 0.25 0.58 0.91 0.64 0.24 2.61 0.34 2.95

1954 0.00 0.38 0.44 0.46 0.20 1.47 0.19 1.66

1955 0.00 0.56 0.31 0.42 0.21 1.51 0.20 1.70

1956 0.00 0.40 0.54 0.61 0.30 1.84 0.24 2.08

1957 0.00 0.61 0.53 0.62 0.24 2.01 0.26 2.27

1958 0.00 0.55 0.42 0.68 0.30 1.95 0.25 2.21

1959 0.00 0.54 0.41 0.54 0.37 1.86 0.24 2.11

1960 0.00 0.42 0.79 0.54 0.25 2.01 0.26 2.27

1961 0.65 0.26 0.49 0.70 0.42 2.52 0.33 2.85

1962 0.00 0.46 0.55 0.61 0.29 1.91 0.25 2.15

1963 0.00 0.49 0.71 0.53 0.30 2.02 0.26 2.28

1964 0.18 0.59 0.75 0.56 0.27 2.34 0.30 2.65

1965 0.00 0.60 0.65 0.39 0.15 1.79 0.23 2.03

1966 0.44 0.26 0.46 0.39 0.17 1.71 0.22 1.93

1967 0.00 0.21 0.84 1.08 0.43 2.56 0.33 2.90

1968 0.28 0.62 0.92 0.33 0.11 2.27 0.30 2.56

1969 0.00 0.39 0.33 0.52 0.18 1.43 0.19 1.62

1970 0.02 0.52 0.49 0.75 0.33 2.12 0.28 2.40

1971 0.55 0.55 1.08 0.42 0.17 2.77 0.36 3.13

1972 0.00 0.35 0.80 0.44 0.20 1.79 0.23 2.03

1973 0.00 0.50 0.54 0.59 0.32 1.94 0.25 2.19

1974 0.00 0.73 0.54 0.54 0.20 2.01 0.26 2.27

1975 0.00 0.35 0.08 0.64 0.27 1.35 0.18 1.52

1976 0.00 0.34 0.08 0.57 0.21 1.19 0.16 1.35

1977 0.33 0.45 0.31 0.44 0.16 1.70 0.22 1.92

1978 0.37 0.36 0.60 0.66 0.33 2.31 0.30 2.61

1979 0.06 0.41 0.38 0.38 0.15 1.37 0.18 1.55

1980 0.00 0.60 0.40 0.48 0.24 1.72 0.22 1.94

1981 0.00 0.56 0.62 0.51 0.17 1.86 0.24 2.11

1982 0.02 0.36 0.52 0.38 0.19 1.47 0.19 1.66

1983 0.00 0.43 0.43 0.66 0.32 1.86 0.24 2.10

1984 1.84 0.35 0.90 0.45 0.20 3.74 0.49 4.22

1985 0.05 0.59 0.73 0.66 0.39 2.42 0.31 2.73

1986 0.19 0.41 0.78 0.61 0.29 2.28 0.30 2.58

1987 0.00 0.57 0.71 0.55 0.21 2.05 0.27 2.31

1988 1.18 0.34 0.34 0.50 0.18 2.53 0.33 2.86

1989 0.56 0.45 0.71 0.50 0.19 2.42 0.31 2.73

Mean 0.22 0.47 0.58 0.55 0.24 2.06 0.27 2.33



Annexure-1B

Yield Series at Bandu PSP Lower Dam site

C.A= 24 Sq.Km Unit = MCM

YEAR JUN JUL AUG SEPT OCT MONSOON NON-MONSOON

ANNUAL

1950 10.06 3.70 5.15 3.19 1.05 23.14 3.01 26.15

1951 1.29 4.02 2.00 3.33 1.27 11.90 1.55 13.45

1952 1.18 3.62 7.68 3.75 2.00 18.23 2.37 20.60

1953 1.70 4.01 6.22 4.36 1.63 17.92 2.33 20.25

1954 0.00 2.60 3.00 3.15 1.36 10.10 1.31 11.41

1955 0.00 3.83 2.14 2.91 1.46 10.33 1.34 11.67

1956 0.00 2.71 3.67 4.17 2.04 12.60 1.64 14.23

1957 0.00 4.20 3.65 4.28 1.64 13.76 1.79 15.55

1958 0.00 3.74 2.89 4.68 2.07 13.39 1.74 15.13

1959 0.00 3.71 2.84 3.71 2.51 12.77 1.66 14.44

1960 0.00 2.91 5.41 3.71 1.73 13.76 1.79 15.55

1961 4.48 1.80 3.33 4.79 2.87 17.27 2.25 19.51

1962 0.00 3.14 3.75 4.17 2.01 13.07 1.70 14.77

1963 0.00 3.33 4.85 3.62 2.04 13.84 1.80 15.64

1964 1.20 4.03 5.16 3.83 1.83 16.05 2.09 18.14

1965 0.00 4.11 4.48 2.69 1.01 12.29 1.60 13.89

1966 3.03 1.78 3.14 2.65 1.14 11.74 1.53 13.27

1967 0.00 1.45 5.75 7.41 2.98 17.59 2.29 19.88

1968 1.95 4.25 6.32 2.27 0.77 15.55 2.02 17.58

1969 0.00 2.66 2.29 3.60 1.25 9.80 1.28 11.08

1970 0.14 3.58 3.39 5.16 2.28 14.55 1.89 16.45

1971 3.75 3.79 7.41 2.88 1.19 19.02 2.48 21.50

1972 0.00 2.42 5.52 3.02 1.34 12.30 1.60 13.90

1973 0.00 3.44 3.67 4.02 2.16 13.30 1.73 15.03

1974 0.00 5.03 3.69 3.71 1.36 13.79 1.79 15.58

1975 0.00 2.42 0.58 4.40 1.84 9.24 1.20 10.44

1976 0.00 2.33 0.54 3.89 1.42 8.18 1.06 9.24

1977 2.28 3.08 2.12 3.05 1.13 11.66 1.52 13.18

1978 2.53 2.44 4.10 4.52 2.25 15.85 2.06 17.91

1979 0.38 2.83 2.59 2.60 1.02 9.42 1.23 10.65

1980 0.00 4.10 2.75 3.30 1.63 11.78 1.53 13.31

1981 0.00 3.83 4.25 3.51 1.19 12.77 1.66 14.44

1982 0.14 2.47 3.53 2.64 1.31 10.09 1.31 11.40

1983 0.00 2.97 2.98 4.54 2.23 12.72 1.66 14.38

1984 12.62 2.42 6.16 3.07 1.36 25.63 3.34 28.96

1985 0.33 4.04 4.98 4.51 2.70 16.56 2.16 18.72

1986 1.32 2.80 5.32 4.20 2.01 15.65 2.04 17.69

1987 0.00 3.93 4.86 3.80 1.43 14.03 1.83 15.85

1988 8.08 2.30 2.32 3.46 1.22 17.37 2.26 19.63

1989 3.83 3.10 4.88 3.46 1.33 16.59 2.16 18.75

Mean 1.51 3.22 3.98 3.75 1.68 14.14 1.84 15.98

CAPACITY

CHAPTER- 4

PROJECT PLANNING AND INSTALLED

Chapter 6 - Power Planning Studies 1

Bandu Pumped Storage Project (4 x 225 MW)


Project Planning and Installed Capacity

6.1 Previous Studies and Documentation

6.1.1 Preliminary Report by WBSEB

In the “Preliminary Report” prepared by the West Bengal State Electricity Board

in 1979 entitled “Power Potential of Pumped Storage Schemes in Purulia

District, West Bengal (5526 MW)”, the Bandu Pumped Storage Scheme was

identified on the Bandu nala stream as one of the schemes with an installed

capacity of about 900 MW.

6.1.2 Pre-Feasibility Report by WBSEDCL

As per the Pre-Feasibility Report on the Bandu Pumped Storage Scheme

prepared by the WBSEDCL in 2012.

The Scheme envisages construction of:

A 55 metre high Rockfill upper dam with central impervious clay core across

river Bandu to provide a live storage of 11.50 million cum with Full Reservoir

Level at 535.00 metre and Minimum Draw Down Level at 515.00 metre.

A 35 metre high Rockfill lower dam with central impervious clay core across

river Bandu to provide a live storage of 11.50 million cum with Full Reservoir

Level at 345.00 metre and Minimum Draw down Level at 320.00 metre.

An underground power house with four numbers Francis type reversible

pump-turbine of capacity 230/250 MW.

3565 metre long headrace and tailrace tunnel for conveyance of water.

6.2 Project Planning

The Planning studies available in the earlier reports on the Bandu Pumped

Storage Scheme have been reviewed and further studies carried out with a

view to optimally developing the potential available at site for pumped storage

scheme.

WAPCOS have reviewed the PFR and studied the project site and following

are the key areas of significance requiring decision making at this stage:

1. Alignment of upper dam

2. Operating levels of Upper Reservoir from impounding considerations.

Chapter – 4




6.2.1 Upper Dam

Location and Reservoir Characteristics

If upper dam is kept at PFR location then the water conductor length would be

on higher side. Hence underground surge shaft both in HRT and TRT may be

required. To avoid HRT surge shaft, the Power house may be kept close to the

upper dam at a suitable location. However, in this case no location is available

for various access tunnels leading to power house as per the site topography.

The shortest possible MAT/CAT length would be in the range of 1.5 to 2 Km.

Accordingly, during the site visit various alternatives were explored to address

the above issues and the dam axis was finalized by shifting the dam axis

further downstream by 1615m.

The upper Dam is located at LEFT Bank latitude 23o 13’ 59.78”and longitude

86o 9’07.17” and Right bank latitude 23o 13’ 16.47”and longitude 86o 9’16.49”.

The area capacity characteristics for the reservoir at Lower Dam location are

enclosed at Annex –I.

6.2.2 Lower Dam

The lower Dam is located at LEFT Bank latitude 23o 14’ 17.23”and longitude

86o 10’15.95” and Right bank latitude 23o 14’ 15.78”and longitude 86o 10’37”.

The area capacity characteristics for the reservoir at Lower Dam location are

enclosed at Annex –II. This location is same as proposed by WBSEDCL.

6.2.3 Water Availability

The water availability in the Bandu stream has been discussed in detail in

Chapter on Hydrology. The yield series developed for the Purulia Project have

been considered for the period 1950-1989. The same has been transposed in

the catchment area proportion of Purulia lower dam to yield runoff series at

proposed both Upper and Lower dam site of Bandu Nala PSP tentatively. The

same would be reviewed/ modified at DPR stage considering the other relevant

and site specific data.

The annual run-off in the stream at the upper dam and Lower dam sites is

summarized below.




Upper Dam Site

The Runoff in the stream at the Upper Dam Site is attached as Annex –III. The

run-off at different dependability conditions is summarized below.

Dependability Year Annual Inflow (mcum)

Monsoon Non-Monsoon Total

90% dependable year 1969-70 1.43 0.19 1.62

75% dependable year 1980-81 1.72 0.22 1.94

50% dependable year 1958-59 1.95 0.25 2.21

Lower Dam Site

The Runoff in the stream at the Upper Dam Site is attached as Annex –IV.

The run-off at different dependability is summarized below.

Dependability Year Annual Inflow (mcum)

Monsoon Non-Monsoon Total

90% dependable year 1969-70 9.80 1.28 11.08

75% dependable year 1980-81 11.78 1.53 13.31

50% dependable year 1958-59 13.39 1.74 15.13

6.2.4 Evaporation Loss

The month wise evaporation losses given at Annex-V have been utilized in the

assessment of evaporation loss from the two reservoirs.

6.2.5 Irrigation Requirement

Based on the preliminary information available, a storage of 1MCM is proposed

to be kept in the upper reservoir. Since it is a close loop pumped storage

scheme and the entire water except that of replenishment of water lost due to

evaporation will be released downstream and can be utilized for irrigation and

water supply.




6.2.6 Environmental Releases

The Storage in the upper and Lower Ponds has been provided for daily

operation of the reversible pump-turbine units. There is no seasonal storage for

power generation and therefore the inflows are stored only to the extent of the

requirement for evaporation. The surplus waters flow down into river course. It

will be ensured that the releases into the river course do not fall below 15% of

the inflows into the pond in any period.

6.2.7 Selection of Project Parameters

The project parameters have been adopted based on the analysis of simulation

operation of the scheme to enable maximize utilization of the potential at the

site.

The selection of installation and operating levels of the upper and lower ponds

have been carried out by carrying out detailed operation simulation studies of

the schemes as discussed in the succeeding paragraph. The installed capacity

of 800MW, 850 MW and 900 MW for 5 hrs operation have been analyzed. The

following details are given for 900 MW option.

Minimum Draw Down Level (MDDL)

Upper Dam

The minimum drawdown for the Upper Pond has been arrived at from the

consideration of silt storage, requirement of water seal above intake, head

variations and reasonable time required for filling of the Pond. Considering a

sediment rate of 950 cum/sq. km/year and CA of 4.2 sq.km, the silt volume in

70 years would only be a small proportion of the dead storage and therefore

does not influence the selection of MDDL. The MDDL has been fixed at

460.83m from the considerations mentioned above.

Lower Dam

The MDDL for the Lower Pond has been fixed at 325 m from the considerations

of silt storage, intake for irrigation, and water seal at the tailrace outlet for

pumping.

6.3 Installed Capacity

The factors influencing the installed capacity of pumped storage scheme at a

site are the requirement of daily peaking hours of operation; operating head,




live pondage in the reservoirs and their area capacity characteristics, which

determine the head variations on the units. The head variation expressed by

the ratio of maximum head to minimum head is preferred as below 1.5.

The daily load factor of operation of the scheme, which in turn determines the

hours of operation in a day, depends on the power system requirements arrived

at from the analysis of the projected system load curve at the time of

commissioning of the units and taking into consideration the mix of generating

stations and their characteristics. Such an involved study is undertaken for

finalization/confirmation of installed capacity at the time of DPR preparation.

However, for the purpose of PFR study, peaking operation of the scheme for 5

hours as adopted in the case of Purulia Pumped Storage scheme has been

considered.

The assessment of storage requirement in the ponds for power generation as

also for other purpose is based on the simulation of operation of the scheme on

daily and annual basis.

6.3.1 Simulation of Daily Operation

The operation of the scheme in either mode viz. generation or pumping, results

in continuous change in the levels of the two reservoirs and consequent

change in the operating head on the machines. The impact of such continuous

variations in head is best captured by simulation of operation of the scheme

considering shorter time intervals of 10 minutes. The detailed preliminary

operation simulation studies of the Scheme have been carried out to

considering 60 time intervals of 10 minutes each for 5 hours generating cycle to

assess the energy generation/pumping energy requirement and determine the

various parameters of the scheme such as operating levels of the two

reservoirs, pondage requirement and the installed capacity. An average

efficiency of reversible units has been considered as 92% in generating mode

and 93% in the pumping mode.

An installed capacity of 900 MW has been adopted based on the simulation

studies carried out for different FRLs and installed capacities to provide

peaking benefits for 5 hours. The Full Reservoir Level of the upper pond has

been considered as 480 m. The lower operating level would be 460.83m and

the corresponding pondage 13.49 mcum. The FRL of the Lower Pond has

been kept at 340.44 m. The daily variation in the Lower Pond level would be

from 340.44 m to 325 m. The MDDL has been kept at 325 m.




Preliminary simulation studies for the scheme for daily operation with an

installation of 900 MW, with FRL 480 m for upper Pond for generating and

pumping mode are enclosed at Annex-VI and Annex – VII. For simulation

studies, the head loss in the water conductor system is tentatively assumed

which varies from 2.08 to 3.56m in generation mode.

The results are summarized below.

The Upper Pond with FRL at 480 m and MDDL 460.83 m has a live

storage capacity of 13.49 mcum.

The head during generating mode would vary from a minimum of 120.39

m to a maximum of 155m. The discharge during generating cycle caries

from 658.33 cumecs to 873.44 cumecs.

The FRL of lower Pond is 340.44 m and MDDL 325 m.

The head during pumping cycle varies from a minimum of 120.39m to a

maximum of 155.00.

The ratio of Maximum to Minimum head is 1.29.

Pumping duration during off peak is 6.5 hours.

The pumping energy requirement is 5850 MkWh.

The cycle efficiency is 76.92%.

The evaporation/downstream irrigation requirements would met without having

impact on the pump turbine operation of the station as these have been

considered in determination of the live capacity of two reservoirs/ponds.

The project parameters are given below.

Upper Dam

FRL (m) 480

MDDL (m) 460.83

Pondage at FRL (mcum) 21.83

Pondage at MDDL (mcum) 8.34

Live Pondage (mcum) 13.49

Lower dam

FRL (m) 340.44

MDDL (m) 325

Pondage at FRL (mcum) 25.19

Pondage at MDDL (mcum) 11.70

Live Pondage (mcum) 13.49




Installed capacity

Installed Capacity (MW) 900

No of units 4

Unit Size (MW) 225

Head (max)- Generating

mode

155.00

Head (Min)- Generating

mode 120.39

Hours of Peaking

Operation 5

Energy Generation (MWh) 4500

Pumping Energy (MWh) 5850

Cycle Efficiency 76.92%

It may be noted that installed capacity at the scheme is sensitive to pondage

and corresponding operating levels determined from the storage characteristics

of the reservoirs. The area capacity characteristics utilized have been

developed from available topo-sheets/ available contour maps. Accurate area

capacity characteristics could be evolved after detailed survey of the reservoir

area and detailed contour plans are developed, an activity to be undertaken

during DPR Stage. Therefore, the installed capacity has been proposed on

conservative side.

It may mentioned that as the power requirements of the system grows, the

energy content for a given installed capacity to cater to the peak of load curve

decreases requiring thereby the operation of the scheme for shorter period

during peaking hours. As mentioned earlier a detailed study at DPR stage

would determine this for the time frame of commissioning of the units. The

peaking hours, if less than 6 hours as per the requirements of the power

system could lead to providing higher installed capacity.




Annex-I

AREA CAPACITY CURVE FOR UPPER RESERVOIR

S.

No.

Contour

Value

(m)

Area

(m2)

Area

(ha)

Interval

(m)

Capacity

(m3)

Comm.

Capacity

(m3)

Comm.

Capacity

(mcm)

1 414 0.00 0.00 - 0.00 0.00 0.00

2 415 6997 0.70 1 2332.33 2332.33 0.002

3 420 21167 2.12 5 67223.10 69555.43 0.070

4 425 38036 3.80 5 145962.38 215517.81 0.216

5 430 68304 6.83 5 262184.48 477702.29 0.478

6 435 104618 10.46 5 429091.66 906793.95 0.907

7 440 163904 16.39 5 665782.89 1572576.84 1.573

8 445 228149 22.81 5 975716.10 2548292.94 2.548

9 450 314352 31.44 5 1350508.68 3898801.63 3.899

10 455 396327 39.63 5 1772744.47 5671546.10 5.672

11 460 496226 49.62 5 2226708.99 7898255.08 7.898

12 465 589824 58.98 5 2711757.71 10610012.79 10.610

13 470 684843 68.48 5 3183712.09 13793724.88 13.794

14 475 786342 78.63 5 3675041.29 17468766.17 17.469

15 480 962654 96.27 5 4365065.43 21833831.60 21.834

16 485 1110787 111.08 5 5179187.24 27013018.85 27.013

17 490 1296152 129.62 5 6011390.54 33024409.39 33.024







Annex II

AREA CAPACITY CURVE FOR LOWER RESERVOIR

S. No. Contour

Value (m) Area (m2) Area (ha) Interval (m) Capacity (m3)

Cumulative

Capacity (m3)

Cumulative Capacity

(MCM)

1 293 0.00 0.00 - 0.00 0.00 0.00

2 295 48401.12 4.84 2 32267.41 32267.41 0.03

3 300 151230.66 15.12 5 475312.03 507579.45 0.51

4 305 264462.89 26.45 5 1026134.66 1533714.10 1.53

5 310 381100.03 38.11 5 1605053.85 3138767.96 3.14

6 315 539136.34 53.91 5 2289197.84 5427965.80 5.43

7 320 624232.52 62.42 5 2905825.14 8333790.94 8.33

8 325 723164.8 72.32 5 3365462.51 11699253.45 11.70

9 330 828994.64 82.90 5 3877388.55 15576642.00 15.58

10 335 914505.1 91.45 5 4357000.85 19933642.84 19.93

11 340 1001998.88 100.20 5 4789594.78 24723237.62 24.72

12 345 1095469.83 109.55 5 5241935.32 29965172.94 29.97

13 350 1215631.33 121.56 5 5775147.98 35740320.92 35.74

14 355 1393489.35 139.35 5 6517744.07 42258064.99 42.26

15 360 1501418.44 150.14 5 7235592.29 49493657.28 49.49







Annex-III

Sheet 1 of 2

Bandu PSP - Annual Inflows at Upper Pond Dam Site

Unit = MCM

YEAR MONSOON NON-

MONSOON ANNUAL

1950-51 3.37 0.44 3.81

1951-52 1.74 0.23 1.96

1952-53 2.66 0.35 3.00

1953-54 2.61 0.34 2.95

1954-55 1.47 0.19 1.66

1955-56 1.51 0.20 1.70

1956-57 1.84 0.24 2.08

1957-58 2.01 0.26 2.27

1958-59 1.95 0.25 2.21

1959-60 1.86 0.24 2.11

1960-61 2.01 0.26 2.27

1961-62 2.52 0.33 2.85

1962-63 1.91 0.25 2.15

1963-64 2.02 0.26 2.28

1964-65 2.34 0.30 2.65

1965-66 1.79 0.23 2.03

1966-67 1.71 0.22 1.93

1967-68 2.56 0.33 2.90

1968-69 2.27 0.30 2.56

1969-70 1.43 0.19 1.62

1970-71 2.12 0.28 2.40

1971-72 2.77 0.36 3.13

1972-73 1.79 0.23 2.03

1973-74 1.94 0.25 2.19

1974-75 2.01 0.26 2.27

1975-76 1.35 0.18 1.52

1976-77 1.19 0.16 1.35

1977-78 1.70 0.22 1.92

1978-79 2.31 0.30 2.61

1979-80 1.37 0.18 1.55

1980-81 1.72 0.22 1.94




Bandu PSP - Annual Inflows at Upper Pond Dam Site

Unit = MCM

YEAR MONSOON NON-

MONSOON ANNUAL

1981-82 1.86 0.24 2.11

1982-83 1.47 0.19 1.66

1983-84 1.86 0.24 2.10

1984-85 3.74 0.49 4.22

1985-86 2.42 0.31 2.73

1986-87 2.28 0.30 2.58

1987-88 2.05 0.27 2.31

1988-89 2.53 0.33 2.86

1989-90 2.42 0.31 2.73




Annex-IV

Bandu PSP - Annual Inflows at Lower Pond Dam Site

Unit = MCM

YEAR MONSOON NON-

MONSOON ANNUAL

1950-51 23.14 3.01 26.15

1951-52 11.90 1.55 13.45

1952-53 18.23 2.37 20.60

1953-54 17.92 2.33 20.25

1954-55 10.10 1.31 11.41

1955-56 10.33 1.34 11.67

1956-57 12.60 1.64 14.23

1957-58 13.76 1.79 15.55

1958-59 13.39 1.74 15.13

1959-60 12.77 1.66 14.44

1960-61 13.76 1.79 15.55

1961-62 17.27 2.25 19.51

1962-63 13.07 1.70 14.77

1963-64 13.84 1.80 15.64

1964-65 16.05 2.09 18.14

1965-66 12.29 1.60 13.89

1966-67 11.74 1.53 13.27

1967-68 17.59 2.29 19.88

1968-69 15.55 2.02 17.58

1969-70 9.80 1.28 11.08

1970-71 14.55 1.89 16.45

1971-72 19.02 2.48 21.50

1972-73 12.30 1.60 13.90

1973-74 13.30 1.73 15.03

1974-75 13.79 1.79 15.58

1975-76 9.24 1.20 10.44

1976-77 8.18 1.06 9.24

1977-78 11.66 1.52 13.18

1978-79 15.85 2.06 17.91

1979-80 9.42 1.23 10.65

1980-81 11.78 1.53 13.31

1981-82 12.77 1.66 14.44




Bandu PSP - Annual Inflows at Lower Pond Dam Site

Unit = MCM

YEAR MONSOON NON-

MONSOON ANNUAL

1982-83 10.09 1.31 11.40

1983-84 12.72 1.66 14.38

1984-85 25.63 3.34 28.96

1985-86 16.56 2.16 18.72

1986-87 15.65 2.04 17.69

1987-88 14.03 1.83 15.85

1988-89 17.37 2.26 19.63

1989-90 16.59 2.16 18.75




Annexure V

Evaporation Losses

Sl. No. Month cm

1 Jan 7

2 Feb 8

3 Mar 14

4 Apr 18

5 May 21

6 Jun 17

7 Jul 11

8 Aug 12

9 Sep 10

10 Oct 9

11 Nov 7

12 Dec 5




Annex-VI

Comparative Summary of three Proposed Installed Plant Capacity

OUTPUT Different Installed Capacity

Value Units

Installed Capacity 800 850 900 MW

Generation Time 5 5 5 Hrs.

Daily Energy Generation(MWh) 4000 4250 4500 MWh

Annual Energy Generation 1460 1551.25 1643 GWH

Daily Pumping Energy(MWh) 5200 5525 5850 MWh

Annual Pumping Energy

Required 1898 2016.63 2135 GWH

Cycle Efficiency 76.92 76.92 76.92 %

FRL(Upper reservoir) 477 477.5 480 m

MDDL(Upper reservoir) 458.15 457.37 460.83 m

FRL(Lower reservoir) 339.07 339.89 340.44 m

MDDL(Lower reservoir) 325 325 325 m

Live Pondage in Reservoir 12.13 12.92 13.49 McM

Dead Storage Upper Reservoir 7.07 6.72 8.34 MCM

Dead Storage Lower Reservoir 11.69 11.69 11.7 MCM

Maximum Head 152 152.5 155 m

Minimum Head 119.08 117.48 120 m

Rated Head 135.54 134.99 137.69 m

Rated Discharge 669.19 713.90 741 m3/s

HRT Dia ( Steel Lined) 7.8 8.1 8.3 m

TRT Dia ( Concrete Lined) 9.2 9.5 9.8 m

Hmax/Hmin 1.27 1.29 1.29

Hmin/Hmax 0.78 0.77 0.78

Velocity in HRT 7.00 6.93 6.85 m/s

Velocity in TRT 5.03 5.03 4.91 m/s




Annex-VII

TURBINE OPERATION

Time Dischar

ge

Upper

Reser

voir

Elevat

ion

Lower

Reser

voir

Elevat

ion

Upper

Reservoir

Capacity

Lower

Reservoir

Capacity.

Upper

Reserv

oir

Capaci

ty

Lower

Reserv

oir

Elevatio

n

Lower

Reserv

oir

Capaci

ty.

Gross

Head

Hea

d

Los

s

Net

Head

Decante

d

volume

Outflo

w from

Upper

Reserv

oir

Cumu

lative

Deca

nted

volum

e

Cumulativ

e

Decanted

volume

Energy

Gener

ation

Cumulat

ive

Energy

Minu

te M3/Sec M M M3 Mm3 M Mm3 M M M M3 Mm3 Mm3 MWh MWh

0 658.33 480.0 325.0 21831499 11699253.45 21.83 325.00 11.70 155 0 0 0

10 671.49 479.5 325.5 21436503 12094250.2 21.44 325.51 12.09 154.04 2.08 151.96 394997 0.39 0.39 394997 150.00 150.00

20 676.22 479.1 326.0 21033611 12497142.1 21.03 326.03 12.50 153.06 2.16 150.90 402892 0.40 0.80 797889 150.00 300.00

30 680.82 478.6 326.6 20627876 12902877.1 20.63 326.55 12.90 152.07 2.19 149.88 405735 0.41 1.20 1203624 150.00 450.00

40 685.51 478.2 327.1 20219383 13311369.3 20.22 327.08 13.31 151.07 2.22 148.85 408492 0.41 1.61 1612116 150.00 600.00

50 690.29 477.7 327.6 19808080 13722673.2 19.81 327.61 13.72 150.07 2.25 147.82 411304 0.41 2.02 2023420 150.00 750.00

60 695.18 477.2 328.1 19393904 14136849 19.39 328.14 14.14 149.06 2.28 146.78 414176 0.41 2.44 2437596 150.00 900.00

70 700.18 476.7 328.7 18976793 14553959.6 18.98 328.68 14.55 148.05 2.31 145.73 417111 0.42 2.85 2854706 150.00 1050.00

80 705.30 476.2 329.2 18556683 14974069.9 18.56 329.22 14.97 147.03 2.35 144.68 420110 0.42 3.27 3274816 150.00 1200.00

90 710.53 475.8 329.8 18133505 15397247.7 18.13 329.77 15.40 146.00 2.38 143.61 423178 0.42 3.70 3697994 150.00 1350.00

100 715.70 475.3 330.3 17707189 15823563.3 17.71 330.28 15.82 144.99 2.42 142.57 426316 0.43 4.12 4124310 150.00 1500.00

110 721.07 474.7 330.8 17277769 16252984 17.28 330.78 16.25 143.97 2.45 141.51 429421 0.43 4.55 4553731 150.00 1650.00

120 726.83 474.2 331.3 16845130 16685623.2 16.85 331.27 16.69 142.88 2.49 140.39 432639 0.43 4.99 4986370 150.00 1800.00

130 732.75 473.6 331.8 16409033 17121719.9 16.41 331.77 17.12 141.79 2.53 139.26 436097 0.44 5.42 5422466 150.00 1950.00

140 738.81 473.0 332.3 15969386 17561367.1 15.97 332.28 17.56 140.69 2.57 138.11 439647 0.44 5.86 5862114 150.00 2100.00




150 745.04 472.4 332.8 15526097 18004656 15.53 332.79 18.00 139.57 2.61 136.96 443289 0.44 6.31 6305403 150.00 2250.00

160 751.44 471.8 333.3 15079071 18451681.9 15.08 333.30 18.45 138.45 2.66 135.79 447026 0.45 6.75 6752428 150.00 2400.00

170 758.01 471.1 333.8 14628208 18902544.4 14.63 333.82 18.90 137.32 2.70 134.62 450862 0.45 7.20 7203291 150.00 2550.00

180 764.76 470.5 334.3 14173405 19357347.7 14.17 334.34 19.36 136.18 2.75 133.43 454803 0.45 7.66 7658094 150.00 2700.00

190 771.79 469.9 334.9 13714552 19816200.9 13.71 334.87 19.82 135.01 2.80 132.21 458853 0.46 8.12 8116947 150.00 2850.00

200 779.30 469.2 335.4 13251478 20279275.2 13.25 335.36 20.28 133.79 2.85 130.94 463074 0.46 8.58 8580022 150.00 3000.00

210 786.99 468.4 335.8 12783896 20746857.1 12.78 335.85 20.75 132.57 2.91 129.66 467582 0.47 9.05 9047604 150.00 3150.00

220 794.91 467.7 336.3 12311704 21219048.8 12.31 336.34 21.22 131.33 2.97 128.37 472192 0.47 9.52 9519795 150.00 3300.00

230 803.08 466.9 336.8 11834759 21695993.6 11.83 336.84 21.70 130.09 3.03 127.06 476945 0.48 10.00 9996740 150.00 3450.00

240 811.53 466.2 337.3 11352909 22177844.1 11.35 337.34 22.18 128.83 3.09 125.74 481851 0.48 10.48 10478591 150.00 3600.00

250 820.26 465.4 337.9 10865991 22664762.1 10.87 337.85 22.66 127.55 3.15 124.40 486918 0.49 10.97 10965509 150.00 3750.00

260 829.72 464.6 338.4 10373834 23156918.4 10.37 338.36 23.16 126.20 3.22 122.98 492156 0.49 11.46 11457665 150.00 3900.00

270 840.05 463.7 338.9 9876000 23654752.7 9.88 338.88 23.65 124.77 3.30 121.47 497834 0.50 11.96 11955499 150.00 4050.00

280 850.83 462.7 339.4 9371967 24158785.6 9.37 339.41 24.16 123.31 3.38 119.93 504033 0.50 12.46 12459532 150.00 4200.00

290 862.05 461.8 339.9 8861470 24669282.7 8.86 339.94 24.67 121.84 3.47 118.37 510497 0.51 12.97 12970029 150.00 4350.00

300 873.44 460.8 340.4 8344239 25186513.9 8.34 340.44 25.19 120.38 3.56 116.83 517231 0.52 13.49 13487260 150.00 4500.00




Annex-VIII

PUMPING OPERATION

Time Dischar

ge

Upper

Reserv

oir

Elevatio

n

Lower

Reserv

oir

Elevatio

n

Upper

Reservoir

Capacity Lower

Reservoir

Capacity.

Upper

Reser

voir

Capac

ity

Lower

Reservo

ir

Elevatio

n

Lower

Reservo

ir

Capacit

y.

Gross

Head

Head

Loss

Net

Head

Decant

ed

volume

Outfl

ow

from

Low

er

Res

ervoi

r

Cumu

lative

Deca

nted

volum

e

Cumulativ

e

Decanted

volume

Cumul

ative

Cumulati

ve

Minut

e M3/Sec M M M3 M3 Mm3 M Mm3 M M M M3 Mm3 Mm3 MWh MWh

0 648.43 460.8 340.4 8344239 25186514 8.34 340.44 25.187 120.38 0.00 0.00 0 0 0

10 653.45 461.5 340.1 8733298 24797455 8.73 340.07 24.797 121.47 2.01 119.46 389059 0.39 0.39 389059 150.00 150.00

20 647.52 462.3 339.7 9125370 24405383 9.13 339.67 24.405 122.60 2.04 120.55 392072 0.39 0.78 781131 150.00 300.00

30 641.36 463.0 339.3 9513883 24016870 9.51 339.26 24.017 123.72 2.01 121.71 388513 0.39 1.17 1169644 150.00 450.00

40 635.36 463.7 338.9 9898697 23632055 9.90 338.86 23.632 124.83 1.97 122.86 384814 0.38 1.55 1554459 150.00 600.00

50 629.53 464.4 338.5 10279912 23250841 10.28 338.46 23.251 125.93 1.93 124.00 381214 0.38 1.94 1935673 150.00 750.00

60 623.93 465.1 338.1 10657629 22873124 10.66 338.07 22.873 127.01 1.90 125.11 377717 0.38 2.31 2313390 150.00 900.00

70 618.92 465.7 337.7 11031988 22498765 11.03 337.68 22.499 127.99 1.86 126.12 374359 0.37 2.69 2687749 150.00 1050.00

80 614.05 466.2 337.3 11403342 22127410 11.40 337.29 22.127 128.96 1.83 127.12 371354 0.37 3.06 3059103 150.00 1200.00

90 609.30 466.8 336.9 11771773 21758980 11.77 336.91 21.759 129.92 1.81 128.12 368431 0.37 3.43 3427534 150.00 1350.00

100 604.65 467.4 336.5 12137351 21393401 12.14 336.52 21.393 130.88 1.78 129.10 365578 0.37 3.79 3793113 150.00 1500.00

110 600.12 468.0 336.1 12500144 21030608 12.50 336.15 21.031 131.83 1.75 130.08 362793 0.36 4.16 4155905 150.00 1650.00




120 595.69 468.5 335.8 12860216 20670536 12.86 335.77 20.671 132.77 1.72 131.04 360072 0.36 4.52 4515978 150.00 1800.00

130 591.36 469.1 335.4 13217630 20313123 13.22 335.40 20.313 133.70 1.70 132.00 357414 0.36 4.87 4873391 150.00 1950.00

140 587.12 469.7 335.0 13572445 19958308 13.57 335.03 19.958 134.63 1.67 132.96 354815 0.35 5.23 5228206 150.00 2100.00

150 582.95 470.2 334.6 13924718 19606034 13.92 334.62 19.606 135.56 1.65 133.91 352274 0.35 5.58 5580480 150.00 2250.00

160 579.06 470.7 334.2 14274490 19256262 14.27 334.22 19.256 136.43 1.63 134.81 349772 0.35 5.93 5930252 150.00 2400.00

170 575.25 471.1 333.8 14621926 18908827 14.62 333.82 18.909 137.31 1.61 135.70 347435 0.35 6.28 6277687 150.00 2550.00

180 571.51 471.6 333.4 14967074 18563678 14.97 333.43 18.564 138.17 1.58 136.59 345149 0.35 6.62 6622836 150.00 2700.00

190 567.85 472.1 333.0 15309982 18220770 15.31 333.03 18.221 139.03 1.56 137.47 342908 0.34 6.97 6965744 150.00 2850.00

200 564.26 472.5 332.6 15650694 17880059 15.65 332.64 17.880 139.89 1.54 138.34 340711 0.34 7.31 7306455 150.00 3000.00

210 560.74 473.0 332.3 15989251 17541501 15.99 332.25 17.542 140.74 1.52 139.21 338558 0.34 7.65 7645013 150.00 3150.00

220 557.29 473.4 331.9 16325697 17205056 16.33 331.87 17.205 141.58 1.51 140.07 336445 0.34 7.98 7981458 150.00 3300.00

230 553.90 473.9 331.5 16660069 16870683 16.66 331.49 16.871 142.42 1.49 140.93 334373 0.33 8.32 8315831 150.00 3450.00

240 550.57 474.4 331.1 16992409 16538344 16.99 331.10 16.538 143.25 1.47 141.78 332339 0.33 8.65 8648170 150.00 3600.00

250 547.31 474.8 330.7 17322752 16208001 17.32 330.72 16.208 144.08 1.45 142.63 330343 0.33 8.98 8978513 150.00 3750.00

260 544.25 475.2 330.3 17651135 15879618 17.65 330.35 15.880 144.86 1.43 143.43 328383 0.33 9.31 9306896 150.00 3900.00

270 541.35 475.6 330.0 17977684 15553068 17.98 329.97 15.553 145.62 1.42 144.20 326549 0.33 9.63 9633446 150.00 4050.00

280 538.34 476.0 329.6 18302494 15228259 18.30 329.55 15.228 146.41 1.40 145.00 324810 0.32 9.96 9958255 150.00 4200.00

290 535.38 476.3 329.1 18625499 14905254 18.63 329.13 14.905 147.19 1.39 145.81 323004 0.32 10.28 10281260 150.00 4350.00

300 532.47 476.7 328.7 18946726 14584027 18.95 328.72 14.584 147.98 1.37 146.60 321228 0.32 10.60 10602487 150.00 4500.00

310 529.60 477.1 328.3 19266206 14264546 19.27 328.31 14.265 148.75 1.36 147.40 319480 0.32 10.92 10921968 150.00 4650.00

320 526.79 477.4 327.9 19583968 13946784 19.58 327.90 13.947 149.53 1.34 148.18 317762 0.32 11.24 11239729 150.00 4800.00

330 524.01 477.8 327.5 19900040 13630713 19.90 327.49 13.631 150.30 1.33 148.97 316071 0.32 11.56 11555801 150.00 4950.00

340 521.29 478.1 327.1 20214448 13316305 20.21 327.09 13.316 151.06 1.32 149.75 314408 0.31 11.87 11870209 150.00 5100.00

350 518.60 478.5 326.7 20527219 13003533 20.53 326.68 13.004 151.82 1.30 150.52 312772 0.31 12.18 12182981 150.00 5250.00

360 515.96 478.9 326.3 20838380 12692373 20.84 326.28 12.692 152.58 1.29 151.29 311161 0.31 12.49 12494141 150.00 5400.00




370 513.36 479.2 325.9 21147955 12382798 21.15 325.88 12.383 153.34 1.27 152.06 309575 0.31 12.80 12803716 150.00 5550.00

380 510.79 479.6 325.5 21455968 12074784 21.46 325.48 12.075 154.09 1.26 152.82 308014 0.31 13.11 13111730 150.00 5700.00

390 508.27 479.9 325.1 21762445 11768308 21.76 325.09 11.768 154.83 1.25 153.58 306476 0.31 13.42 13418206 150.00 5850.00

PLANNING AND DESIGN OF CIVIL STRUCTURES

CHAPTER- 5

Chapter – 7: Design of Civil Structures 1


(4 x 225 MW)


7.1 The Scheme

The Bandu Pumped Storage Scheme is the third Pumped Storage scheme being

taken-up by WBSEDCL amongst the four schemes identified in the Ayodhya Hills. The

first Scheme named Purulia Pumped Storage Project (4 x 225 MW) on Kistobazar

Nala already in successful operation since 2007-08. The second scheme named

Turga Pumped Storage Scheme is under preconstruction stage.

The third scheme i.e Bandu Nala Pumped Storage has been contemplated

considering utilization of run-off water of the catchment during monsoon period that

discharges through the Bandu nala/river and its tributaries.

Initially a preliminary stage study was carried out by erstwhile WBSEB in year 1979. A

prefeasibility Report has been finalized by WBSEDCL based on available resources/

data.

WBSEDCL has entrusted the work of updation of pre-feasibility report of bandu

Pumped Storage Project. WAPCOS reviewed the earlier PFR by WBSEDCL

and carried out preliminary studies on optimum location and type for major

structures such as upper dam, alternatives to existing lower dam and a shorter

water conductor system, from both technical and economical viewpoints, based

on the available site characteristics such as topography, geology and other

conditions. An optimum general layout for the project is selected based on the

site characteristics aforementioned.

Major structures such as upper and lower dams, waterway system and power

house are put under the preliminary optimization study independently of each

other. Basic designs of civil structures are carried out based on the locations

and types of structures which were selected in the optimum general layout.

7.2 River Diversion:

A) Upper Dam:-

Care of river during construction on the dam is proposed through stage diversion

method. Initially, the present river bed will be used as first diversion channel, while

embankment on both banks is being raised. Subsequently in the second stage the

river diversion through the channel will be made after closing embankment gap in the

central part. Embankment will thereafter be raised up to the top level in the entire

length, except in the diversion channel. Final closure in this part will be carried out in

the last stage. Alternatively in place of second channel a coffer dam will be

constructed of suitable height in the river portion and embankment construction will be

carried out to close the gap. Since water coming to the river is very less, the height of

coffer dam will be such that the inflow water can be accommodated with in reservoir of

Chapter - 5

Design of Civil Structures



(4 x 225 MW)


coffer dam. The detail of diversion scheme including second diversion channel will be

taken up at DPR stage.

B) Lower Dam:-

Diversion during construction on lower dam is proposed through an excavated

channel. The diversion is explained in the following steps;

1. The present river bed will be used as the first diversion channel for first

dry and monsoon season, while excavation on right bank will be taken

up to rock line for Spillway arrangement.

2. The Foundation level of Non-overflow block adjacent to earthen-Rock fill

Dam will be taken up to deepest bed level of river. The necessary

modification in foundation level adjacent overflow block will be

incorporated for ease of construction.

3. Once the excavation of Right bank Spillway is completed with stripping

of ground for Rock-Fill dam in left and Right bank, excavation of an

approach Channel and spill channel on the downstream will be carried

out to divert water.

4. The construction of Coffer dam shall be taken up during second dry

season and simultaneously construction of Rock fill Dam will be taken up

including upstream Rip rap.

5. In the third dry season, Non-overflow block in the excavated channel will

be raised up to a predetermined level, so that the construction of Rock

fill dam will not hamper due to flood in third monsoon. The level of Non-

overflow blocks will be kept below the level of adjacent overflow block

and Rock fill dam so that flood only passes through Non-overflow Block.

6. It will ensure that when the Non-overflow Block being used for diversion

are raised, all the works below it are completed in the upstream so as to

allow the water to fill up in the reservoir.

The detail of diversion scheme including second diversion channel will be taken up at

DPR stage.

C) Environmental Flow:-

1. Bottom Outlets shall be provided in lower spillway dam below the MDDL

in Lower Reservoir and in Power Block below the MDDL in upper

Reservoir respectively. Bottom outlet will be regulated by manually

(Hydraulically/mechanically) operated Gate. Environmental flow may be

regulated through this bottom outlet during construction. Size and

location will be decided based on the environmental flow at the time of

detailed design.



(4 x 225 MW)


D) Modality of Impounding of Reservoirs:-

Based on the preliminary data available for hydrological studies, the annual

yield at upper dam axis for various dependability has been calculated and

presented in Hydrology chapter. It may be noted that the annual yield at upper

dam axis is low which impose longer impounding period of Upper Reservoir. To

overcome the longer impounding period, the following additional modality may

be adopted to fill the reservoir.

In place of excavated channel for diversion of river during construction, a

coffer dam will be constructed of suitable height in the river portion

upstream of Upper dam location. The construction of embankment will

take place simultaneously with filling of temporary reservoir at coffer

dam. Once the embankment achieves the suitable height, stage filling of

reservoir will start. The 5.0m level difference shall be kept in reservoir

filling level and embankment for ease in construction.

Temporary Reservoir constructed in Pre-construction stage: -A

temporary reservoir in Upstream of upper dam axis with in Upper

Reservoir will be created. The impounding of reservoir shall be taken in

advance to meet the project specific requirement. The schedule of filling

and storage capacity for Reservoir shall be evaluated to meet the

scheduled of generation.

The suitability of imponding procedure shall be studied at Detailed Design

stage.

Impounding of Lower Reservoir shall be done in by stage filling. The annual

yield at lower dam axis is high which allow impounding of lower reservoir

through stage filling.

7.3 Selection of Layout - General

The project envisages construction of two reservoirs at different levels and a water

conductor system to connect them through underground power house. The proposed

project envisages construction of a dam across Bandu Nala (upper dam) with FRL at

EL-480m and a dam across Bandu Nala (lower dam) with FRL at EL-340.44 m. Water

will be diverted from the upper reservoir through HRT – pressure Shaft to an

underground power house located in between upper and lower reservoir to generate

900MW (225MWx4) of power. Tail water will be diverted through a TRT to the lower

reservoir. Owing to pumped storage nature of the project the water from lower

reservoir will be pumped through TRT-Reversible Turbines-Pressure Shaft-HRT to

upper reservoir in off peak hours.

Bandu Pumped Storage Project is composed of the following civil structures in

particular:

Upper Dam

Lower Dam



(4 x 225 MW)


Intake

Headrace Tunnel- Steel lined

Penstock Tunnel

Tailrace Tunnel

Tailrace Outlet

Powerhouse

Transformer Room

As for the layout and structures, refer to Drawing No. WAP/D&RE/Bandu-02.

7.3.1 : Selection of Optimum General Layout

General layout selected based on Geological, Topographical, and hydrological

metrological aspects with techno-economic feasibility. PFR stage layout has been

reviewed and following changes need to be incorporate in the PFR.

1. Relocation of Upper Dam axis

2. Impounding levels of Reservoirs

Rest all other aspects seems to be in order and may not pose any problem at PFR

stage. It is recommended that these are only preliminary findings and a detailed review

will be taken at DPR stage.

A) Review of Upper dam Location of PFR:

Upper Dam axis is suggested at Upper reaches of Bandu nala with FRL

535.00m which may impose technical and uneconomical problems. The upper

Dam Axis has the followings demerits;

1. If upper dam is kept at PFR location then the water conductor length

would be on higher side. Hence underground surge shaft both in HRT and

TRT may be required.

2. The topography just below the upper dam on both banks does not offer

higher elevation and is in the range of 460-480m. Therefore, providing

HRT surge shaft may not be feasible.

3. To avoid HRT surge shaft, the Power house may be kept close to the

upper dam at a suitable location. However, in this case no location is

available for various access tunnels leading to power house as per the

site topography. The shortest possible MAT/CAT length would be in the

range of 1.5 to 2 Km.This will have significant adverse impact on project

construction time and cost estimates and longer tunnels are undesirable

proposition.



(4 x 225 MW)


The new upper dam axis (selected) will overcome these demerits.

B) Selection of Layout Location:-

The topographical, geological & hydrological aspects discussed amongst the experts

to evolve the most attractive layout from hydroplaning perspective. The team of

Interdisplinary experts visited the site and deliberated at length the possible

alternatives of the various project components with respect to their location &

type. Accordingly, a map showing various possible layouts is shown in Plate-I

(Chapter 5:-Drawing No. WAP/Bandu/GA/01).

The layout has been suggested over left bank due to the following reasons.

1. Based on the available maps, there is comparatively higher cultivation and

habitation presence on the right bank and hence possibility of private land

acquisition exists.

2. More possible locations for siting the UGPH on left bank with adequate

vertical rock cover.

3. As per GSI expert, we may encounter low cover reaches comparatively

along the layout.

For Closed loop pumped storage, the L/H Ratio for the Layout at PFR stage

was 18.66 (3565/191). The final layout which have proposed having L/H ratio

12.40 (1687/134.45).

In view of the above reasons, the present Layout has been chosen. For details,

Please refer drawing no.WAP/D&RE/Bandu/02 and 03.

7.3.2 Type of Structure – Dam

The Dam Structures were considered for creating two Reservoirs of the Project.

For both Lower& Upper Reservoir –Rock-fill with Central Clay Core type, has

been considered.

For selecting the type of each Dam Structure, the following were taken into

considerations.

To restrict Cost, Dam to be built with locally available quantity of

Construction Materials viz. Clay, Rock fill etc.

The Dam structure best suited to the site geological features etc.



(4 x 225 MW)


7.3.3 Layout of Dam, Spillway, Power House and Reasons for choice of

the Site

7.3.3.1 Lower Dam & Spillway :

The Location of Lower dam axis at PFR Stage was N- 23˚ 14’ 30”, E- 86˚ 10’

30” which will provide required live storage. It is observed that the most suitable

location for Lower Dam Axis just 50m downstream of PFR stage dam axis is at

Left Bank N- 23˚ 14’ 17.237”, E- 86˚ 10’ 15.95” and Right Bank N- 23˚14’

15.781”, E- 86˚10’ 37.007” which can provide the required Live Storage and

better geological considerations.

The Rockfill with Clay core type has been chosen on cost consideration over

concrete which may increase the project cost. The c and MDDL is kept at EL-

340.44.00 m and EL-325.0 0m which create required live poundage 13.49

MCM at Tail pond. The deepest level at lower dam axis is EL-293m with top of

dam as 346.00m. The maximum height of lower dam is 53m and length

644.00m. The Dead storage in lower Reservoir at MDDL-325m is 11.70MCM. A

Bottom Outlet has been kept in lower spillway below the MDDL in Lower

Reservoir for environmental flow.

The section of the Rock fill dam proposed for lower dam is a conventional zonal

section with clay core and shell portion of Rockfill material, having upstream

slope of 2.25H:1V and downstream slope 2H:1V. The centrally located core

with upstream and downstream slope each of 0.25:1 has been prepared. It has

the advantage of providing higher pressures at the contact between the core of

Upstream and Downstream shell material, thus reducing the possibilities of

seepage and piping.

A 1.5m thick sand filter followed by 2.5m thick crushed stone/gravel. Filter has

been provided along the upstream and downstream face of clay core. This is

considered sufficient from design as well as construction point of view. A

horizontal filter blanket has been provided to drain out water from the vertical

filter and body of dam as well as to take care the seepage through the

foundation.

The bed of the COT is proposed to be taken 1000mm inside the hard rock

/impervious strata. Consolidation grouting of depth 10 to 12m is also proposed.

The bed of the toe drain is proposed at least 600mm below the stripped level.

The slope provided may be reviewed once more data is available at DPR

stage. The typical section of the Upper dam is shown in the drawing No-

WAP/D&RE/Bandu/08.

The Spillway for Lower Dam is Located near the right abutment on the original

course of Bandu Nala. Considering the design flood of 600 m3/s, an ungated

ogee overflow Spillway has been considered. Seven no of ogee ungated



(4 x 225 MW)


spillway of 15m length each has been kept at Lower dam to discharge the

design flood of 600 m3/s. Pier width has been kept 3.0m. Crest level of ogee

spillway has been kept at Elevation-340.44 m and Maximum water level is EL-

343.00 m with 3 m free board. The Spillway arrangement is shown in drawing

no- WAP/D&RE/Bandu/09.For protection of the embankment, Rip-Rap has also

been provided in up and down stream. The Maximum overflow and Non-

overflow Block of the lower Dam spillway is shown in the drawing No-

WAP/D&RE/Bandu/10 & 11.

7.3.3.2 Upper Dam & Spillway

For finalizing the location of the Upper Dam Axis the following three alternative

dam axes were studied.

Three locations for upper dam axis have been selected as under.

Dam axis Alternative1- This alternative is selected where the bed level is

adopt EL 420m and good rock exposure exists at the abutments. However,

this site is on the d/s of village Chhatni on right bank, therefore the FRL has to

be kept below 490m. The option of saddle dam was also considered but due

to presence of a nala on the right bank which may pose problems to the

saddle dam it was declined. Another advantage of this site is that the length of

WCS gets comparatively reduced and is in the range of 2000m.

Dam axis Alternative 2- This alternative is selected where the bed level is

about EL 440m. This site is on the u/s of village Chatni therefore the FRL can

be raised to EL 510m. A saddle dam will be required to isolate the habitation.

However the length of WCS gets comparatively increased and is in the range

of 2600m.

Dam axis Alternative 3- The Final Axis (Selected) was the nearest from the

Lower dam with Length/Head ratio is about 12.40. Hence, this is considered on

safe side and have following advantages;

1. To shift the left abutment of upper dam further downstream of the

Bandu Nala.

2. Though the upper dam length is marginally on higher side as compared

to PFR dam axis but considering the low average height, geology and

availability of construction material it may not pose any problem.

3. With this arrangement the Water Conductor length can be reduced

significantly and the underground surge shafts in HRT (2 nos) and TRT

(2 Nos.) can be dispensed with.



(4 x 225 MW)


4. Power house access tunnels (MAT, CAT etc.) lengths would get

reduced significantly, thus the construction time and cost would be

reduced.

In view of above the alternative-III has now been chosen in the present study.

However, the same may be reviewed at the DPR stage when more subsurface

and topographical data is available. Accordingly, a drawing showing location of

all three axis is shown in Plate-I (Chapter 5:-Drawing No. WAP/Bandu/GA/01).

The Location of Upper dam axis at PFR Stage was N- 23o 13’ 16”, E- 86o 08’ 35”.

As aforesaid above that the alternate-III of Dam axis is most suitable location

for Upper Dam which overcome the demerits of Dam axis at PFR stage. The

new location of Upper dam axis is at Left Bank N- 23˚ 13’ 59.786”, E- 86˚ 09’

07.17” and Right Bank N- 23˚13’ 16.47”, E- 86˚09’ 37.16.49” just 1765.30m

downstream of dam axis in PFR along the course of bandu nala which can

provide the required Live Storage and attributes better techo-economic

considerations.

The Rockfill with Clay core type has been chosen on cost consideration over

concrete which may increase the project cost. The FRL and MDDL is kept at

EL-480.00m and EL-460.83m which create required live poundage 13.49MCM

at head pond. The deepest level at upper dam axis is EL-414.00m with top of

dam as 485.00m. The maximum height of upper dam is 71m and length 1776m

at EL-485.00m (Dam Top). The provision of Irrigation storage of 1 MCM for

downstream requirement has been kept. The Minimum draw down level for

irrigation depletion is EL 458.75m.The Dead poundage in headpond at MDDL-

460.83m is 8.34MCM. A Provision Bottom Outlet has been kept in Power

Block below the MDDL at Upper Reservoir.

The section of the Rock fill dam proposed for Upper dam is a conventional

zonal section with clay core and shell portion of Rockfill material, having

upstream slope of 2.25H:1V and downstream slope 2H:1V. The centrally

located core with upstream and downstream slope each of 0.25:1 has been

prepared. It has the advantage of providing higher pressures at the contat

between the core of Upstream and Downstream shell material, thus reducing

the possibilities of seepage and piping.

A 1.5m thick sand filter followd by 2.5m thick crushed stone/gravel. Filter has

been provided along the upstream and downstream face of clay core. Which is

considered sufficient from design as well as construction point of view. A

horizontal filter blanket has been provided to drain out water from the vertical

filter and body of dam as well as to take care the seepage through the

foundation.



(4 x 225 MW)


The bed of the COT is proposed to be taken 1000mm inside the hard rock

/impervious strata. Consolidation grouting of depth 10 to 12m is also proposed.

The bed of the toe drain is proposed at least 600mm below the stripped level.

The slope provided may be reviewed once more data is available at DPR

stage. The typical section of the Upper dam is shown in the drawing No-

WAP/D&RE/Bandu/04.

The Spillway for Upper Dam is Located near the right abutment on the original

course of Bandu Nala. Considering the design flood of 130 m3/s, an ungated

ogee overflow Spillway has been considered. Two no of ogee ungated spillway

of 11m length each has been kept at Lower dam to discharge the design flood

of 130 m3/s. Pier width has been kept 2.0m. Crest level of ogee spillway has

been kept at Elevation-480.00m and Maximum water level is EL-482.00m with

3m free board. The Spillway arrangement is shown in drawing no-

WAP/D&RE/Bandu/05.For protection of the embankment, Rip-Rap has also

been provided in up and down stream. The Maximum overflow and Non-

overflow Block of the Upper Dam spillway is shown in the drawing No-

WAP/D&RE/Bandu/06 & 07.

7.3.4 Power Intake

Two number of intake structures have been proposed in left side of deepest

course in Reservoir. A channel has been proposed to guide the flow towards

intake mouth.

Optimum layout requirements has considered to suit the alignment of the Water

Conductor in fixing the alignment of Power Intake. To minimize the dead

storage and cutting of Channel to feed in Intake mouth, Power Intake shifted

towards the deepest course of Nala.

The intake position further takes in consideration the following:

To minimize the dead Storage and excessive excavation for flow

Channel.

An inlet is to be vertically arranged for avoidance of adverse impact on

sedimentation, vortex and air inflow to waterway.

The PSP Intake is composed of the following structures:

Inlet with trash rack and anti-vortex louver

Conduit between the end of inlet and Intake Gate

Intake Gate Shaft

Based on the parameters minimum submergence required has been calculated

as per BIS codal practice and Gorden formula for symmetric flow. The center

line of the intake has been accordingly fixed at EL 440.15m.



(4 x 225 MW)


The inlet and outlet is designed in accordance with the guideline proposed by

Central Research Institute of Electric Power Industry in Japan which has been

mostly applied to design for intakes and outlets of a lot of pumped storage

power station. The main consideration of design criteria are as follows;

Waterway of a pumped storage power plant is pressure one, so an inlet

of a pumped storage power plant also comes to pressure type.

Concerning vertical arrangement of an inlet for a pressure conduit.

Sufficient water cushion shall be provided for withdrawal of requisite

discharge without any vortex formation. Water depth from sill of an inlet

to the minimum water level should be 1.5 to 2.0 times as high as internal

diameter.

Velocity of flow through trash rack shall not be more than 1.0 metre/sec

in normal condition.

Entry through Intake shall be stream lined such that head loss is

minimum.

Invert level of intake shall be fixed in such a way that it does not attract

much of the silt during withdrawal of water.

An intake of a pumped storage power station has the following characteristics in difference from a conventional hydraulic power station; - Both an intake and a tailrace outlet are to function as an intake as well

as an outlet since directions in generating and pumping modes are exact reverse even though hydraulic feature is quite different between water intake and discharge.

- There is a possibility that vortex easily comes into being for the reason that water depth between a surface to an intake comes to small near the maximum draw-down level.

- It is difficult that water flow discharged from an inlet or outlet evenly diffuses into a reservoir because flow velocity of a pumped storage power station is generally faster than that of a conventional hydraulic power station.

As a result, the inlet structure is designed and the drawing is provided in

drawing no.WAP/D&RE/Bandu/12 and 13.

7.3.5 Water Conductor System

Alignment and profile of the waterway is also one of major elements to be

optimized in the selection of optimum general layout, because it governs other

layouts of structures such as switchyard, access tunnel etc. therefore,

comparative study on location of the waterway on both banks of Bandu Nala is



(4 x 225 MW)


conducted. Then, an optimum profile of the waterway is selected through

comparative study among various alternatives.

The alignment of the waterway from the intake to the tailrace outlet is studied under the following conditions; • Length of waterway is tried to be shortest. • The portion of water way is aligned in such a way that it has a no bends. • Both intake and tailrace outlet are aligned in such a way that pumping

and generation mode have a favorable flow characteristics. • There are four reversible units. Accordingly 2 pressure shafts bifurcate in

to four manifolds to feed the four units. In the d/s side four draft tunnels extend from the powerhouse and enter into tail race tunnels. Consequently, two tailraces emanate to take water to lower reservoir.

• Longitudinal axis of the powerhouse cavern is to be aligned about N15W-S15E in accordance with the foliation strike resulting in straight waterway.

• It goes without saying that the powerhouse cavern is to be positioned with enough rock cover on the powerhouse cavern for stability of the cavern. In this regard, the Power house has been kept below rock ledge of 450 m so that sufficient cover shall be available over Power house cavern. The excavated crown level is kept at EL-330m.The height of cavern is 48m. The rock cover on the powerhouse cavern has kept more than twice of height of the cavern plus some allowance.

The Longitudinal section along the alignment of the waterway from the intake to the tailrace outlet is shown in drawing no.WAP/D&RE/Bandu/03. `

The locations of power intake and tailrace outlet are to be selected in the area

where stable topographical and geological conditions can be obtained, so as to

be able to ensure the stable and safe water flow.

Water Conductor system is aligned through Upper dam body (Non-overflow

section of Concrete) at EL 440.15m in a slope 8:1 (H: V).

An underground powerhouse is conceivable and the size of main cavern will be

a large one with about 48m in height, 23 in width and 157m in length

approximately, so that the powerhouse location is to be selected in a massive

mountain body.

A twin tunnel is to be adopted as waterway system taking into consideration the

reliability of steady electricity supply from the large sized power plant.

A long waterway sometimes involves excess water hammer/ inner pressure

and water column segregation. Hence the shortest possible waterway has been

chosen. Based on the preliminary available data, the preliminary transit studies

envisage no Surge Tank/ Surge Chamber in the scheme. However, detailed

transient studies shall be taken up during DPR stage.



(4 x 225 MW)


7.3.6 Head Race Tunnel (Steel lined) Cum Pressure Shaft

Two number 8.30 m diameter Steel Liner emanates from intake at invert EL

436m. Initial stretch of 70 m of Liner is horizontal which accommodate the Gate

Shaft thereafter the liner negotiate a slope 8:1 (H:V) and moves for a inclined

length of 522.00m . Further, the liner has a bend of 45 degree from EL-

383.50m to Centre line EL-293m. Thereafter the liners run horizontally for a

distance of 143 meter upto the proposed location of bifurcation point. The each

liner is bifurcated into two branches of 5.90m.

Steel lining has been proposed to the entire length of HRT. The thickness of

steel lining is being assessed keeping in view the internal pressure including

water hammer and external pressure acting in the event of sudden dewatering

of Tunnel. The typical support details of HRT and Pressure Shaft is shown in

drawing no.WAP/D&RE/Bandu/14 and 15.

Diameter of 8.30 m as proposed for penstock is based on the velocity

consideration however economic diameter studies may be done at DPR stage.

Plate thickness is being assessed considering both internal water pressure plus

increase in head due to water hammer as well as external pressure.

Design criteria

The hydraulic and structural design of pressure shaft/penstock is based on

following criteria:

- Steel liner has been designed to take the entire internal pressure

independently without any rock participation

- Steel liner has been capable to withstand maximum external pressure

under empty condition

- Penstock has been designed for loading condition at mid span and at the

supports where additional stresses are developed.

- Sickle plate for penstock manifold should take care of all unbalanced

forces at the point of bifurcation.



(4 x 225 MW)


7.4 Underground Power House & Underground Transformer Hall

Four, each of 225 MW capacity with vertical axis Reversible Francis Turbine

have been proposed to be installed in the power house. The proposed layout

includes the following underground openings:

Machine hall cavern (160M X 22.5M X 48M)

Underground Transformer Hall (134M X 18M X 18M)

Bus duct

Draft tube tunnels (7.0M Diameter)

Unit tail race tunnels (7.0m Diameter)

Combined Tail race Tunnel (2 Nos- 9.80m Diameter- 628m length each)

Main Access Tunnel ( Size-8.0m X 8.5m, Length-975M)

Construction adits (Size-7X 7.5M, Total Length – 1010M)

Cable Tunnel (Size 6.0X6.5M, Length-445M)

7.4.1 Machine Hall Cavern

The machine hall cavern would be 160m in length, 22.5m in width and the

overall height of the power house cavity from the lowest excavation of the

turbine pit would be 48m. The generating units would be spaced at 24.00m

center to center. The entrance to the Machine hall cavern shall be through Main

Access Tunnel (MAT). The auxiliary rooms shall be located at different floors

provided on the services bay side of the machine hall cavern.

The penstock for each generating unit would enter the power house

horizontally making an angle with the power house longitudinal direction and

accommodate the main inlet valve in the machine hall. The penstock for each

unit will terminate into a distributor feeding the turbine nozzles. The center line

of the horizontal penstocks entering the power house cavity would be EI. 293m

in line with nozzles of the turbines.

The roof of machine hall cavern has been provided with a circular arch shape

with crown rise of 5m from the spring level. The roof and walls of the power

house cavern are supported by systematic rock bolting and shotcreting (SFRS).

Where the rock mass is of poor quality (‘Q’ value from 1.0 to 2.0), the roof is

supported with the combination of shotcrete (SFRS), rock bolts and steel ribs.

Provision of drainage holes in regular way has also been made for roof and

walls for draining the rock mass adjoining the cavern.

RCC columns of size 1000mm x 1500mm are proposed for supporting the EOT

crane beam. A clearance of about 500 mm has been provided between the



(4 x 225 MW)


column edge and excavated rock surface to take care of the convergence of

power house walls.

7.4.2 Transformer Cavern

The transformer cavern would be 134m long, its width and height being 18m

and 18m, respectively. It accommodates 4 unit transformers at EI. 308.00m.

The roof arch of this cavity would be of circular arch shape with 5.0m rise of

crown from the spring level. As in the machine hall cavity, the roof and walls of

the transformer cavity are also supported by systematic rock bolting and

shotcreting (SFRS). Where the rock mass is of poor quality (‘Q’ value from 1.0

to 2.0), the roof is supported with the combination of shotcrete (SFRS), rock

bolts and steel ribs. Provision of drainage holes in regular way has also been

made for roof and walls for draining the rock mass adjoining the cavern.

7.4.3 Tail Race Tunnel

The water coming out of the draft tube is again fed into the lower reservoir

through two Tail Race tunnels. Being a reversible Francis turbine the flow in the

unit tail race & manifold d/s of TRT gate is under pressure. The size of tail race

tunnel after manifold has been worked in such a way that there will be pressure

flow in the entire length of TRT. The bed slope of TRT was fixed in such a way

that cross-section be minimum for safe velocity of concrete lined tunnel. The

invert level of outlet shall be kept below the MMDL water level of lower

reservoir The TRT should maintain pressure-flow condition for all discharges.

9.8m Circular-shape concrete lined tunnel has been provided for the purpose.

The velocity in the tunnel for design discharge of 902.51 cumecs will be 5.06

m/s.The typical support details of HRT is shown in drawing

no.WAP/D&RE/Bandu/16.

The outlet structure is designed and the drawing is provided in drawing

no.WAP/D&RE/Bandu/17 and 18.

4120

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DENSE MIXED JUNGLE

DENSE MIXED JUNGLE

MARANGARA NALA (RAJABANDH NALA)

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MDDL - 325.00m

LIVE STORAGE - 13.49MCM

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SUBMERGENCE AREA - 101.00Ha.

FRL - 480.00m

MDDL - 460.83m

LIVE STORAGE - 13.49MCM

DEAD STORAGE - 8.34MCM

SUBMERGENCE AREA - 96.27Ha.

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BATCHING PLANTS,SITE OFFICES

STOCK PILES

PROJECT OFFICE BUILDINGS

PROJECT ROAD

ROCK QUARRY AREA

BORROW AREA

LEGEND:-

MUCK DISPOSAL AREA

WAPCOS LIMITED

BANDU PUMPED STORAGE PROJECT (900 MW)

CONSULTANTS

(A GOVERNMENT OF INDIA UNDERTAKING)

WEST BENGAL STATE ELECTRICITYDISTRIBUTION COMPANY LIMITED

DEGN.

DRAWN.

DATE: FEB.2018

CHKD. SUBM.

APPD.

DRG.NO.WAP/D&RE/BANDU/02

REV.NO.

KEY PLAN FOR PROJECT COLONY AT SIRKABAD

PROJECT LAYOUT PLAN

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MDDL 460.83M (GENERATION)

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GATE SHAFT

MDDL 458.75M (IRRIGATION)

DAM TOP EL.485.00MMWL 482.00M

MDDL 460.83M (GENERATION)

24

44

WAPCOS LIMITED


CONSULTANTS

(A GOVERNMENT OF INDIA UNDERTAKING)

WEST BENGAL STATE ELECTRICITYDISTRIBUTION COMPANY LIMITED

DEGN.

DRAWN.

DATE: FEB.2018

CHKD. SUBM.

APPD.

DRG.NO.WAP/ D&RE/BANDU/03

REV.NO.

A

B

DETAIL - A

DETAIL - B

WATER WAY PROFILE

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COST ESTIMATE

CHAPTER- 7

Chapter –10: Cost Estimate 1



10.1 Project Cost

A summary of the cost estimate, including direct and indirect charges for the Civil & Electro-mechanical works at December, 2017 Price Level is been given below:

Item Estimated Cost (Rs. In lakh)

Option: I Considered all 4 machines are

Fixed Speed Machines

Option: II Considered 2 (Two) machines are Variable Speed machines + 2 (Two) machines are Fixed

Speed Machines

Civil Works 203211 203693

Electro-mechanical Works

168777 204189

Power evacuation 9000 9000

Total 380988 416882

The estimate has been prepared to arrive at the capital cost of Bandu Pumped Storage Project, on BanduNala in Ayodhya hills in district Purulia, West Bengal. The estimate is of Pre-feasibility level and has been prepared on the basis of “Guide Lines for preparation of cost estimates for River Valley Projects” published by Central Water Commission, Govt. of India, New Delhi. The Abstract of Cost is enclosed at in the relevant chapter of this report. The above cost does not include the cost of Transmission.

10.2 Basis of Estimate

The estimate for Civil & Hydro-mechanical works have been prepared: i. The rates have been adopted by updated to current price level from the

recently approved Turga Pumped Storage Projects, District Purulia, West Bengal which having similar parameters and working conditions.

ii. The rates of materials are inclusive of Taxes as applicable. iii. Interest and escalation during construction period not considered.

Quantity estimate have been carried out by calculating the quantities of different work items involved. Unit rate corresponding to major item of works have been worked out by analysis of rate at current price level from the recently approved Turga Pump Storage Projects, District Purulia, West

Chapter-07

Cost Estimate




Bengal. Some rates of major item of works, lump sum provision have been made based on the other similar projects.

The following guidelines have been referred for the preparation of this cost estimate:

1. “Guidelines for preparation of project estimates for River Valley Projects” dated March 1997 by Central Water Commission, Govt. of India.

2. “Guide Lines for preparation of Detailed Project Report of Irrigation and Multipurpose projects” 2010 by Central Water Commission, Govt. of India.

10.3 Classification of Civil Works Into Minor Head/Sub Heads

The cost has been classified into direct and indirect charges and covered under the following minor heads:

Direct Charges

I. Works II. Establishment III. Tools and Plants IV. Receipts and Recoveries on Capital Account Indirect Charges I. Capitalized Value of Abatement of Land Revenue II. Audit and Account Charges 10.4 Direct Charges

10.4.1 I -Works

Option-I Current Cost = Rs.190045lakh

Option-II Current Cost = Rs.190496lakh. The minor head I-Works has been subdivided in to the following detailed subheads:

10.4.2 A-Preliminary

Current Cost:Rs.3084lakh

Under this head provision has been made for surveys and investigations to be conducted at DPR stage and later to arrive at the optimum of the project components. Provision for in-house Design & Engineering and consultancy charges has been kept under this head as 2% of cost of C & J Works.

10.4.3 B-Land





This covers the provision for acquisition of land/lease charges for construction of the project, structures, colonies, offices etc. and the provision for Rehabilitation and Resettlement (R&R) of Project Affected Persons.

10.4.4 C- Works


This sub-head covers the cost of Upper Dam, Lower Dam, Saddle Dam and associated Hydro-mechanical equipment.

10.4.5 J- Power Plant Civil Works

Option –I, Current Cost:Rs.88130lakh with all 4 machines are Fixed Speed Machines

Option –II, Current Cost: Rs.88567lakh with Considered 2 (Two) machines are

Variable Speed machines + 2 (Two) machines are Fixed Speed Machines.

This covers the cost of Civil Works of Power Tunnel Intake structures, Head Race Tunnel, Surge Shaft, Pressure Shaft, Power House, Transformer Cavern & Tail Race Tunnel etc. along with associated Hydro-mechanical equipment. 10.4.6 K- Buildings

Current Cost:Rs. 11000lakh

Lump sum amount has been made towards temporary and permanent buildings (both residential and non-residential) proposed to be built in colonies for various locations of the project area. The buildings included under the permanent category are all those buildings, which will be subsequently utilized during the state of running and maintenance of the project.

10.4.7 M- Plantation

Current Cost:Rs.50.00 lakh

The provision under this head includes cost of plantation in colonies, along approach roads, landscaping and improvements of area around powerhouse.




10.4.8 O- Miscellaneous

Option –I Current Cost:Rs.3075lakh Option –II Current Cost: Rs.3084lakh

Under this head provision is generally made to cover the cost of the following miscellaneous works:

a) Capital cost of electrification, water supply, sewage disposal, firefighting equipment etc.

b) Repair and maintenance of electrification water supply, sewage disposal, medical assistance, recreation, post office telephone office security arrangements, firefighting, inspection vehicles, schools, transport of labour etc.

c) Other services such as laboratory testing, R&M of Guest House and transit camps, Community center and photographic instruments as well as R&M charges etc.

As the estimate is of Pre-feasibility level, percentage provision @ 2% of C-J works has been considered towards head O- Miscellaneous.

10.4.9 P- Maintenance

Option –I Current Cost:Rs.1672lakh Option –II Current Cost:Rs.1677lakh

For maintenance of buildings, roads and other structures during construction period, provision @ 1% of C-works, J-Power Plant civil works, K- buildings R- Communication have been kept.

10.4.10Q- Special T&P

Current Cost:Rs.1000.00lakh

It is assumed that the work will be carried through Contracts and accordingly nominal provision for procurement of necessary equipment for taking up the work at the earliest by the contractor have been made. The total expenditure towards this will be recovered from the contractors and the same is credited under receipt and recoveries.

Adequate provision is made for inspection vehicles and cost for resale of vehicles is accounted for under receipt and recoveries.

10.4.11 R-Communication




Current Cost:Rs.2500.00lakh

Provision under this head covers the cost of construction of roads and bridges for project works. The provision is Lump sum only at this stage based on preliminary assessments as detailing shall be done later on.

10.4.12 X-Environment and Ecology

Current Cost:Rs. 11000 lakh

Provision under this head covers Bio-diversity Conservation, Creation of green belt, Restoration of Construction Area, Catchment Area Treatment and Compensatory Afforestation etc.

10.4.13 Y-Losses on Stock

Current Cost:Rs.418lakh for Option-I. Current Cost: Rs.419lakh for Option-II.

The provision under this head have been made @ 0.25% of the cost of I-Works less A-Preliminary, B-Land, O-Miscellaneous, M-Plantation, P-Maintenance, Q-Special T&P and X-Environment and Ecology. 10.5 II-Establishment Option-I Current Cost:Rs. 11253lakh Option-II Current Cost:Rs. 11280lakh

Provision for establishment including establishment of cost control cell at the project and Head Quarter Level has been made as per “Guide lines for Preparation of Detailed Project Report of Irrigation and Multipurpose Project” by CWC @ 6% of I-Works less B-Land.

10.5.1III- Tools &Plants

Current Cost:Rs. 200.00 lakh

The provision is distinct from that under Q-Special T&P and is meant to cover cost of survey instruments, camp equipment and other small tools & plants.

10.6 V-Receipt &Recoveries Current Cost:Rs. 250.00 lakh

The provision under this head cover the estimated recoveries by way of resale of temporary buildings, transfer of construction equipment, inspection vehicles, generators etc.




10.7 Indirect Charges Option-I Current Cost:Rs.1963lakh Option-I Current Cost: Rs.1967lakh Provisions under this head have been made for capitalized value of abatement of land revenue. Besides, provision for Audit & Account Charges has been made at 1% of the cost of I-Works.

10.8 Electro-Mechanical Works Option-I Current Cost:Rs. 168777 lakh Option-II Current Cost: Rs. 204189 lakh

The total cost of Electro-Mechanical works at December, 2017 level works out to be Rs.168777lakh considering all 4 machines are Fixed Speed Machines and Rs. 204189lakh considering 2 machines are Variable Speed machines plus 2 machines are Fixed Speed Machines which includes, the cost of main Electro-Mechanical equipmentsuch as turbines, generators, transformers etc. based on the prevailing market prices in India and abroad.

Suitable provision for transportation, erection and commissioning charges, freight and insurance etc. have been adequately made as per general guidelines issued by CEA. Provision for establishment and Audit and Account charges for the electro-mechanical works have also been made under this cost separately.

10.9 Evacuation System

Current Cost: Rs. 9000 lakh

The total cost of 400 kV Transmission lines is Rs. 9000 lakh considering two nos. of double circuit Quad Moose / Twin HTLS (From Bandu PSP to Turga PSP and Bandu PSP to New PPSP 400 kV GIS).

Sl. No. DETAILED HEAD OF WORKSAmount (Rs. Lacs)

A CIVIL WORKS1 DIRECT CHARGES

I-WORKSA-Preliminary 3084B-Land 2500C-Works including HM Works 65616J-Power Plant Civil Works 88130K-Building 11000M-Plantation LS 50O-Miscellaneous 3075

P-Maintenance during construction @1% of I Works-(A+B+O+M+Q+X+Y) 1672

Q-Special T&P 1000R-Communication 2500X-Environment & Ecology 11000Y-Losses on Stock @0.25% of C,J,K & R 418

Total of I-Works 190045

II-ESTABLISHMENT @ 6% OF (I-WORKS LESS B LAND) 11253

III-TOOLS & PLANTS LS 200IV-SUSPENSE 0V-RECEIPT & RECOVERIES (-) -250

Total of Direct Charges 201248

2 Indirect Charges

(a) Capitalised value of abatement of land revenue @ 5% of cost of culturable land

63

(b) Audit & Account Charges (@ 1% of I-Works) 1900Total of Indirect Charges 1963

Total Cost (Direct charges + Indirect Charges) 203211Total Cost Civil Works 203211

A Civil Works 203211B Electrical Works 168777C Transmission line 9000

Total Cost 380988


GENERAL ABSTRACT OF COST (Option-I)

Sl. No. DETAILED HEAD OF WORKSAmount (Rs. Lacs)

A CIVIL WORKS1 DIRECT CHARGES

I-WORKSA-Preliminary 3084B-Land 2500C-Works including HM Works 65616J-Power Plant Civil Works 88567K-Building 11000M-Plantation LS 50O-Miscellaneous 3084

P-Maintenance during construction @1% of I Works-(A+B+O+M+Q+X+Y) 1677

Q-Special T&P 1000R-Communication 2500X-Environment & Ecology 11000Y-Losses on Stock @0.25% of C,J,K & R 419

Total of I-Works 190496

II-ESTABLISHMENT @ 6% OF (I-WORKS LESS B LAND) 11280

III-TOOLS & PLANTS LS 200IV-SUSPENSE 0V-RECEIPT & RECOVERIES (-) -250

Total of Direct Charges 201725

2 Indirect Charges

(a) Capitalised value of abatement of land revenue @ 5% of cost of culturable land

63

(b) Audit & Account Charges (@ 1% of I-Works) 1905

Total of Indirect Charges 1967

Total Cost (Direct charges + Indirect Charges) 203693

Total Cost Civil Works 203693A Civil Works 203693B Electrical Works 204189C Transmission line 9000

Total Cost 416882

GENERAL ABSTRACT OF COST (Option-II)


ENVIRONMENTAL & ECOLOGICAL ASPECTS

CHAPTER- 8

Chapter -11 : Environment 1



11.1 NEED FOR THE STUDY The proposed project, while providing planned power generation could also lead to a variety of adverse environmental impacts. However, by proper planning at the inception and design stages and by adopting appropriate mitigatory measures in the planning, design, construction and operation phases, the adverse impacts can be minimized to a large extent, where as the beneficial impacts could be maximized. The present Chapter outlines the information on baseline environmental setting and assessment of impacts likely to accrue during project construction and operation phases of the proposed project. The Chapter also outlines the framework of Environmental Management Plan (EMP) for mitigation of adverse impacts. An Environmental Monitoring Programme too been delineated in the present chapter for implementation during project construction and operation phases. 11.2 STUDY AREA The Study Area considered for the Environmental Assessment study shall comprise of the following:

Area to be acquired for various project appurtenances Submergence area for upper and lower reservoirs Area within 10 km periphery of upper and lower reservoir site Area within 10 km periphery of various project appurtenances

11.3 ENVIRONMENTAL BASELINE STATUS 11.3.1 METEROLOGY Meteorologically, the year can be divided into three distinct seasons. Winter season sets in from the month of November and continues upto February, followed by summer season from March to June. The area receives rainfall under the influence of south-west monsoons from mid-June to September. The temperature and rainfall in project area district is given in Table-1.

CHAPTER – 08

ENVIRONMENTAL AND ECOLOGICAL ASPECTS




Table-1: Temperature and rainfall details in project area district

Month Mean Temperature (ºC) Rainfall (mm)

No. of Rainy Days Maximum Minimum

January 25.3 12.4 12.9 1.2 February 28.5 15.2 19.3 1.8 March 34.0 19.8 21.6 2.1 April 38.5 24.5 32.8 2.5 May 39.6 26.5 47.9 3.5 June 36.2 26.2 190.4 10.0 July 32.1 25.1 284.3 16.4 August 31.5 24.8 315.4 15.9 September 31.6 24.4 280.9 12.7 October 31.1 21.9 89.6 4.9 November 28.6 17.0 12.6 1.0 December 25.6 12.9 3.2 0.4 Average 31.9 20.9 Total 1347.1 72.4

The temperature continuously increases from March upto the month of May, which is the hottest month of the year. The mean maximum and minimum monthly temperatures in the month of May are 39.6oC and 26.5oC respectively. With the onset of monsoons in mid-June, there is a drop in the temperature. January is the coldest month of the year, with the monthly mean of daily maximum and minimum temperatures being 25.3oC and 12.4oC respectively. The annual average rainfall in the project area is 1347.1 mm. Majority the annual rainfall is received under the influence of south-west monsoons. The maximum rainfall is received in the months from July to September. 11.3.2 Forest Types The forests in the proposed project area fall in Purulia Forest Division of West Bengal. As per classification, the forest under this division is Northern tropical Dry Deciduous Forest type and Dry peninsular sal forest. The major forest types found in study area are briefly described in the following paragraphs.




5B Northern Tropical Dry Deciduous Forests This is a dry deciduous forest in which the upper canopy is light but continuous in the climax form. The second storey is rarely found and an irregular often broken canopy and smaller height. The undergrowth is generally thin and shrubby including some evergreen xerophytic species. These forests belong to the following forest types: 5B/C1 Dry Sal-bearing forest This is a low quality forest dominated by Shorea robusta. It is often broken up into pure groups or mixed patches of varying extent in which either sal or its associates predominate. It may further be sub-divided into the following sub-types:

5B/C1c Dry Peninsular Sal Forest 5B/C2 Northern Dry Mixed Deciduous Forest

5B/C1c Dry Peninsular Sal Forest This sub-type occurs on shallow soils that have been derived from crystalline and metamorphic rocks wherever soil moisture conditions are unfavourable for the development of moist sal, even in areas with higher rainfall. The soil often laterite and is sometimes calcareous. The main tree associates found in the first storey are, Buchanania latifolia, Bombax ceiba, Madhuca indica, Schleichera trijuga, Semecarpus anacardium, Shorea robusta, Terminalia chebula and T. tomentosa. Second storey comprises of the species including Butea monosperma, Diospyros tomentosa, Holarrhena pubescens, Mallotus philippinensis, etc. 5B/C2 Northern Dry Mixed Deciduous Forest This is an open, dry deciduous forests, with thin upper canopy but fairly complete. Most trees have low spreading crowns. The important tree species occurring in the first storey are Adina cordifolia,Bauhinia variegata, Bridelia retusa, Butea monosperma, Ficus bengalensis, Flacourtia indica, Lannea coromandelica, Lagerstroemia parviflora, Shorea robusta, Terminalia bellerica and Terminalia tomentosa. Second storey comprises of Acacia leucopholea, Casearia graveolens, Ficus hispida, F. semicordata, Holarrhena pubescens, Mallotus philippinensis, Randia dumetorum, and Zizypus mauritiana. Climbers are few and represented by Butea superba, Combretum decandrum, Derris scandens, Smilax prolifera, etc. The




shrub layer is represented by Carissa spinarum, Chromolaena odoratum, Clerodendrum viscosum, Costus speciosus, Lantana indica and Woodfordia fruticosa. The list of floral species reported in the study is given in Table-11.2.

Table -11.2: List of Floral species recorded from the proposed project area

Plant Species Local Name Family Habit Acacia catechu Khair Mimosaceae Tree Adina cordifolia Haldu Rubiaceae Tree Aegle marmelos Bel Rutaceae Tree Aglaia roxburghiana Priyangru Meliaceae Tree Albizia odoratissima Jang Siris Mimosaceae Tree Albizia procera Safed Siris Mimosaceae Tree Albizzia lebbek Kala siris Mimosaceae Tree Altsonia scholaris Saptparni Apocynaceae Tree Artocarpus lacucha Dhao Moraceae Tree Azadirachta indica Meliaceae Tree Barringtonia actangula Neora Myrtaceae Tree Bauhinia variegata Khairwal Caesalpiniaceae Tree Bombax ceiba Semal Bombacaeae Tree Bridelia retusa Kassi Euphorbiaceae Tree Buchanania latifolia Piyal Anacardiaceae Tree Butea monosperma Palas Papilionaceae Tree Canthium glabrum - Rubiaceae Tree Casearia graveolens Chilla Flacourticeae Tree Cassia fistula Sonari Rubiaceae Tree Cordia rothii Liar Boraginaceae Tree Croton caudatus Putla Euphorbiaceae Tree Dalbergia sissoo Sisham Fabaceae Tree Diospyros melanoxylon Tendu Ebenaceae Tree Ficus auriculata Dumari Moraceae Tree Ficus bengalensis Bargad Moraceae Tree Ficus racemosa Gular Moraceae Tree Flacourtia jangomas Coffe plum Flacouticeae Tree Garuga pinnata Kharpat Burseraceae Tree Gmelina arborea Gambari Verbenaceae Tree Holarrhena pubescens Kurchi Apocynaceae Tree Holoptelea integrifolia - Ulmaceae Tree




Plant Species Local Name Family Habit Lannea coromandelica Doka Anacardiaceae Tree Madhuca indica Mahwa Sapotaceae Tree Mallotus philippinensis Kamla Euphorbiaceae Tree Mangifera indica Aam Anacardiaceae Tree Melia azedarach Bakayan Meliaceae Tree Oroxylum indicum Sonpatti Bignoniaceae Tree Phoenix sylvestris Khajur Arecaceae Tree Phyllanthus emblica Amla Euphorbiaceae Tree Pongamia pinnata Papri Papilionaceae Tree Rhus chinensis Amlio Anacardiaceae Tree Schleichera trijuga Kusum Sapindaceae Tree Semecarpus anacardium Bhela Anacardiaceae Tree Shorea robusta Sal Dipterocarpaceae Tree Streblus asper Sahora Moraceae Tree Syzygium cumini Kala Jamb Myrtaceaer Tree Tectona grandis Teak Verbenaceae Tree Terminalia arjuna Arjun sal Combretaceae Tree Terminalia bellirica Bahera Combretaceae Tree Terminalia chebula Haritaki Combretaceae Tree Terminalia tomentosa Asan Combretaceae Tree Abutilon indicum Malvaceae Shrub Agave sisalana Agavaceae Shrub Allophyllus cobbe - Sapindaceae Shrub Annona squamosa Annonaceae Shrub Asparagus racemosus Liliaceae Shrub Bixa orellana Bixaceae Shrub Calotropis gigantean Asclepiadaceae Shrub Carissa spinarum Auka Kuli Apocynaceae Shrub Cassia occidentalis - Caesalpiniaceae Shrub Chromolaena odoratum - Asteraceae Shrub Clerodendrum viscosum Ghato Verbenaceae Shrub Combretum roxburghii Combretaceae Shrub Datura fastuosa Solanaceae Shrub Flemingia strobilifera Fabaceae Shrub Glycosmis pentaphylla Rutaceae Shrub Helicteris isora Sterculiaceae Shrub Ipomoea carnea - Convolvulaceae Shrub Lantana indica Lantana Verbenaceae Shrub Leea alata - Leeaceae Shrub Maytenus senegalensis - Celastraceae Shrub




Plant Species Local Name Family Habit Mimosa rubicaulis - Mimosaceae Shrub Piper longum Piperaceae Shrub Randia dumetorum Maidan Rubiaceae Shrub Vitex negundo Sandbhalu Verbenaceae Shrub Woodfordia fruticosa Dhora Lythraceae Shrub Zizyphus mauritiana Ber Rhamnaceae Shrub Ageratum conyzoides - Asteraceae Herb Achyranthes aspera - Amaranthaceae Herb Aerva lanata - Amaranthaceae Herb Alternanthera sessilis - Amaranthaceae Herb Andrographis paniculata - Acanthaceae Herb Anisomeles ovata - Lamiaceae Herb Argemone mexicana - Papaveraceae Herb Artemisia indica - Asteraceae Herb Bacopa monnieri - Scrophulariaceae Herb Barleria lupulina - Acantaceae Herb Bidens pilosa - Asteraceae Herb Biophytum reinwarrdtii - Oxalidaceae Herb Boerhavia diffusa - Nyctaginaceae Herb Cajanus cajan - Fabaceae Herb Cajanus scarabaeoides - Fabaceae Herb Cassia tora - Caesalpiniaceae Herb Centella asiatica - Apiaceae Herb Chenopodium album - Chenopodiaceae Herb Coleus aromaticus - Lamiaceae Herb Colocasia esculenta - Araceae Herb Commelina benghalensis - Commelinaceae Herb Costus speciosus - Zingiberaceae Herb Crassocephalum crepidioides - Asteraceae Herb Cyanotis axillaris - Commelinaceae Herb Eclipta alba - Asteraceae Herb Evolvulus numlaria - Convolvulaceae Herb Galium asperuloides - Rubiaceae Herb Gloriosa superba - Liliaceae Herb Hedychium coronarium - Zingiberaceae Herb Hemidesmus indicus - Asclepiadaceae Herb Hydrocotyle nepalense - Apiaceae Herb Impatiens balsamina - Balsaminaceae Herb Indigofera tinctoria - Fabaceae Herb




Plant Species Local Name Family Habit Leonotis nepetifolia - Lamiaceae Herb Leucas cephalotes - Lamiaceae Herb Ocimum canum - Lamiaceae Herb Ruellia prostrata - Acanthaceae Herb Scoparia dulcis - Scrophulariaceae Herb Sida cordata - Malvaceae Herb Sida veronicifolia - Malvaceae Herb Tylophora indica - Asclepiadaceae Herb Urena lobata - Malvaceae Herb Arthraxon hispidus - Poaceae Grass Bothriochloa pertusa - Poaceae Grass Chrysopogon aciculatus - Poaceae Grass Chrysopogon serrulatus - Poaceae Grass Cynodon dactylon - Poaceae Grass Cyrtococcum accrescens - Poaceae Grass Dactyloctenium aegypticum - Poaceae Grass Digitaria sanguinalis - Poaceae Grass Eragrostis nardoides - Poaceae Grass Eragrostis unioloides - Poaceae Grass Kyllinga brevifolia - Poaceae Grass Oplismenus compositus - Poaceae Grass Paspalidium flavidum - Poaceae Grass Paspalum scrobiculatum - Poaceae Grass Sporobolus diander - Poaceae Grass Asparagus racemosus Satmuli Liliaceae Climber Butea superba Lat Plas Fabaceae Climber Cissampelos pareira Ekleja Menispermaceae Climber Combretum decandrum Atena Combretaceae Climber Cuscuta reflexa Haldi algusi Cuscutaceae Climber Derris scandens Noalata Fabaceae Climber Dioscorea bulbifera Rat-alo Dioscoreaceae Climber Hoya pendula - Asclepiadaceae Climber Jasminum pubescens - Oleaceae Climber Porana paniculata Bridal creeper Convolvulaceae Climber Pueraria tuberosa Tirra Fabaceae Climber Rubia cordifolia Manjith Rubiaceae Climber Smilax prolifera - Smilacaceae Climber Stephania hernandifolia Khandi Menispermaceae Climber




11.3.2 Fauna Mammals

Mammalian fauna is represented by a large number of faunal species. Rhesus Macaque, Common Langur, Jungle Cat, Wild Boar, Grey Mongoose, Brush-tailed Porcupine, Indian Hare etc. Asian Elephant is found in lower reaches and is not reported from the project or its surrounding area. The list of mammal species reported in the Study Area is given in Table-11.3.

Table-11.3: List of Mammal species reported in the Study Area

Common name Family Scientific name Conservation

Status IUCN IWPA

Rhesus macaque Cercopithecidae Macaca mulatta LC II Common Langur Colobidae Presbytia entellus LC II Jungle Cat Felidae Felis chaus LC II Golden Jackal Canidae Canis aureus LC II Indian Fox Canidae Vulpes bengalensis LC III Common Mongoose Herpestidae Herpestes edwardsii LC IV Wild Boar Suidae Sus scrofa LC III Indian Hare Leporidae Lepus nigricollis LC IV Indian Palm Squirrel Sciuridae Funambulus palmarum LC IV Five Stripped Squirrel Sciuridae Funambulus pennantii LC II Bandicoot Rat Muridae Bandicota bengalensis LC V Indian house rat Muridae Rattus rattus LC V Indian Flying Fox Pteropodidae Pteropus giganteus LC V Short-nosed Fruit Bat Pteropodidae Cynopterus sphinx LC IV Indian Pygmy Bat Vespertilionidae Pipistrellus tenuis LC V Yellow House Bat Vespertilionidae Scotophilus kuhlii LC V *Note: –Recorded only from Forest Working Plan, however, not direct cited, LC – Least Concern, NT- Near Threatened, VU- Vulnerable




Avi-fauna Avi faunal species belonging to families Anatidae, Ardeidae, Charadridae, Rallidae, Phalacrocoracidae etc are common in lower region in open places and wetland while members of Picidae, Megailaimidae, Strigidae, etc are inhabitants of woody forests in the catchment. Dominant bird species observed during the survey are Blue jay, dove, myna, house crow, house sparrow, lapwing, little egret and grey wagtail etc. The list of bird species found in study area is given in Table-11.4.

Table-11.4: List of Avi-Fauna reported in the Study Area

Family/Scientific Name Common Name Residential Status

Threat Status

Accipitridae Accipiter badius(Gmelin) Shikra R LC Gyps bengalensis Bengal Vulture R LC Aquila refax Towny Eagle- Oukab R LC Anatidae Sarkidiornismelanotos Comb Duck R LC Ardeidae Egrettagarzetta(Linnaeus) Little Egrets R LC Egrettaintermedia Intermediate Egret R LC Bubulcuscoromandus(Linnaeus) Cattle Egret R LC ArdeolagrayiiLinnaeus Indian Pond Heron R LC Burhinidae Burhinusoedicnemus Indian Stone-curlew R LC Capitonidae Megalaimahaemacephala Coppersmith Barbet R LC Cisticolidae Priniasocialis Ashy Prinia R LC Ciconiidae Mycterialeucocephala Painted Stork LM LC Anastomusoscitans Asian Openbill LM LC Phalacrocoracidae Phalacrocoraxniger(Vieillot) Little Cormorant R LC PhalacrocoraxfuscicollisStephens Indian Shag

/Cormorant R LC

Columbidae Columba liviaGmelin Blue Rock Pigeon R LC Treronphoenicoptera Harial -green pigeon





Threat Status

Streptopeliasenegalensis(Linnaeus) Little Brown Dove R LC Streptopeliadecaocto EuraisionCollor dove R LC Streptopeliachinensis Spotted Dove R LC Corvidae CorvusmacrorhynchosWagler Jungle Crow R LC CorvussplendensVieillot House Crow R LC Dendrocittavagabunda(Latham) Indian Treepie R LC Cuculidae Eudynamysscolopacea(Linnaeus) Asian Koel R LC Centropussinensis(Stephens) Greater Coucal R LC Hierococcyxvarius(Vahl) Brainfever Bird R LC Strigidae Athenebrama(Temminck) Spotted Owlet R LC Bubo benghalensis(Linnaeus) Indian Eagle-Owl R LC Alcedinidae Alcedoatthis(Linnaeus) Small Blue Kingfisher R-S LC Halcyon smyrnensis(Linnaeus) White breasted

Kingfisher R-S LC

Daniidae Laniuscristatus Brown Shrike R LC Muscicapidae Copsychussaularis Oriental magpie-robin R LC Meropidae MeropsorientalisLatham Small green Bee-eater R LC Family : Coraciidae Coraciasbenghalensis(Linnaeus) Indian Roller-Blue jay R LC Family : Upupidae UpupaepopsLinnaeus Common Hoopoe R LC Family : Picidae Woodpecker Dendrocoposnanus(Vigors) Brown-capped Pygmy R LC Dendrocoposmahrattensis(Latham) Yellow-fronted Pied R LC Dinopiumbenghalense(Linnaeus) Lesser Golden-backed R LC Family: Passeridae Subfamily : Passerinae Passer domesticus(Linnaeus) House Sparrow R LC Subfamily : Ploceinae PloceusPhilippinus(Linnaeus) Baya Weaver R LC Family : Motacillidae AnthusrufulusVieillot Paddyfield Pipit R LC





Threat Status

Family : Pycnonotidae Pycnonotuscafer(Linnaeus) Red-vented Bulbul R LC Family : Laniidae Turdoidescaudatus(Dumont) Common Babbler R LC Turdoidesstriatus(Dumont) Jungle Babbler R LC Orthotomussutorius(Pennant ) Common Tailorbird R LC Phylloscopusfuligiventer Smoky Warbler R LC Family : Nectariniidae Nectariniaasiatica(Latham) Purple Sunbird R LC Family:Phasianidae Francolinuspondicerianus(Gmelin) Grey Francolin-Teeter R LC PavocristatusLinnaeus Marrah Peacock R LC Family : Charadriidae Vanellusindicus(Boddaert) Red-wattled Lapwing R LC Metopidiusindicus Bronjed winged jacana Psittaculidae Psittaculakrameri(Scopoli) Rose-ringed Parakeet R LC Sturnidae Acridotheresfuscus(Wagler) Jungle Myna R LC Acridotherestristis(Linnaeus) Common Myna R LC Sturnus contra Linnaeus Asian Pied Starling R LC Sturnuspagodarum(Gmelin) Brahminy Starling R LC Gracupica contra(Linnaeus) Pied Myna R LC Family : Dicruridae DicrurusmacrocercusVieillot Black Drongo R LC Dicruruscaerulescens(Linnaeus) White-bellied Drongo R LC Dicrurusleucophaeus Ashy drongo R LC Family : Oriolidae Oriolusoriolus(Linnaeus) Eurasian Golden

Oriole R LC

Orioluskundoo Indian Golden Oriole M LC Estrildidae Lonchuramalabarica Indian Silverbil R LC Irenidae Chloropsis cochinchinensis Blue-winged Leaf Bird R LC Megalaimidae Megalaimahaemacephala Coppersmith Barbet R LC




Abbrs. Residential status: R- Resident; LM-Local Migrant; Status Abbrs.: LC- Least Concern, NR Not Rare, NT-not threatened.

Francolinuspondicerianus Chloropsiscochinchinensis

Psittacula eupatria Centropus sinensis

Dicrurus macrocercus Phylloscopusfuligiventer

Common bird species recorded in the vicinity of proposed project




Green Bee Eater Little Green Bee-eater

Purple Sunbird Bramhy Starling

Red-vented Bulbul Coppersmith Barbet-





Indian Robin

Eurasian Golden Oriole Common Myna

Dendrocittavagabunda PiiedMyna





White Breast Kingfisher Indian Golden Oriole

Intermediate Egrets Asian Openbill-Anastomusoscitans

Vanellusindicus(Boddaert) Red napped Ibis / Black Ibis





11.3.5 FISHERIES The major fish reported from the water bodies in the study area include Barilius bendelisis, Chela cachius, Puntius spp., Nemacheilus spp.etc. 11.3.6 DEMOGRAPHY The total population of the district is 2536516 residing in 449895 households. The average household size is 5.6. Male and female population comprises of 51.2% and 48.8% of the total population respectively. The population of infants and children less than 6 years of age comprises about 16.1% of the total population. The scheduled caste and scheduled tribe population constitutes about 18.29% and 18.27% of the total population. The overall literacy rate in the district is 46.6%, while the male and female literacy rate is 61.9% and 30.6% respectively. The working and non working population in the district comprises about 44.5% and 55.5% of the total population respectively. Amongst the working population, the main workers and marginal workers constitute 57.3% and 42.7% respectively. A large majority (89.9%) of the population in the district lives in the rural areas, while the remaining are urbanites (10.1%). The demographic profile of Purulia district is shown in Table–11.5.

Table-11.5: Demographic profile of Purulia district

Indicators Total Percentage Number of Households 449895 Total Population 2536516 Male Population 1298078 51.2 Female Population 1238438 48.8 Population < 6 Years 408803 16.1 Population Scheduled Caste 463956 18.29 Population Scheduled Tribe 463452 18.27 Literate Population 1182284 46.6 Literate Male 803494 61.9 Literate Female 378790 30.6 Total Working Population 1127488 44.5 Main Workers 645506 57.3 Marginal Workers 481982 42.7 Non Working Population 1409028 55.5 Urban Population 255426 10.1 Rural Population 2281090 89.9




11.4 PREDICTION OF IMPACTS Prediction is essentially a process to forecast the future environmental conditions of the project area that might be expected to occur because of the implementation of the project. Based on the project details and the baseline environmental status, potential impacts as a result of the construction and operation of the proposed project have been identified. 11.4.1 IMPACTS ON WATER ENVIRONMENT a) Construction phase

i) Sewage from labour camps

The project construction is likely to last for a period of 5 years. The peak labour strength likely to be employed during project construction phase is about 1000 workers and 250 technical staff. Considering family size as 4, total increase in population due to migration of labour population would be of the order of 5000. The employment opportunities in the area are limited. Thus, during project construction phase, some of the locals may get employment. It has been observed during construction phase of many of the projects; the major works are contracted out, who bring their own skilled labour. However, it is only in the unskilled category, that locals get employment. The construction phase, also leads to mushrooming of various allied activities to meet the demands of the immigrant labour population in the project area. The domestic water requirement has been estimated as 135 lpcd. Thus, total water requirements work out to 0.68 mld. It is assumed that about 80% of the water supplied will be generated as sewage. Thus, total quantum of sewage generated is expected to be of the order of 0.54 mld. The BOD load contributed by domestic sources will be about 225 kg/day. It is assumed that the sewage is discharged without any treatment for which, the minimum flow required for dilution of sewage is about 0.5 cumec. It is recommended to commission units for treatment of sewage generated from labour camps. In the proposed project, sewage is proposed to be treated, prior to disposal.




ii) Effluent from crushers During construction phase, at least one crusher will be commissioned at the quarry site by the contractor involved in construction activities. It is proposed that only crushed material would be brought at construction site. Water is required to wash the boulders and to lower the temperature of the crushing edge. About 0.1 m3 of water is required per ton of material crushed. The effluent from the crusher would contain high-suspended solids. The effluent, if disposed without treatment can lead to marginal increase in the turbidity levels in the receiving water bodies. It is proposed to treat the effluent from crushers in settling tank before disposal so as to ameliorate even the marginal impacts likely to accrue on this account. iii) Effluent from Batching Plants

During construction phase, batching plants will be commissioned for production of concrete. Effluent containing high suspended solids shall be generated during operation and cleaning of batching plants. It is proposed to treat the effluent before disposal to ameliorate even the marginal impacts likely to accrue on this account. iv) Effluent from Fabrication Units and Workshops

The fabrication units and workshops which shall be functional during construction phase will generate effluents with high suspended solids and oil and grease level. It is proposed to treat the effluent in oil & Grease separator unit from fabrication units and workshops prior to disposal. b) Operation phase

The major sources of water pollution during project operation phase include: Effluent from project colony. Impacts on reservoir water quality.

i) Effluent from project colony

During project operation phase, due to absence of any large-scale construction activity, the cause and source of water pollution will be much different. Since, only a small number of O&M staff will reside in the area in a well-designed colony with




sewage treatment plant and other infrastructure facilities, the problems of water pollution due to disposal of sewage are not anticipated. In the operation phase, about 100 families (total population of 500) will be residing in the project colony. About 0.08 mld of sewage will be generated. The total BOD loading will be order of 22.5 kg/day. It is proposed to provide biological treatment facilities including secondary treatment units for sewage so generated from the BOD load after treatment will reduce to about 2.2 kg/day. It shall be ensured that sewage from the project colony be treated in a sewage treatment plant so as to meet the disposal standards for effluent. Thus, with commissioning of facilities for sewage treatment, no impact on receiving water body is anticipated. Thus, no impacts are anticipated as a result of disposal of effluents from the project colony. ii) Impacts on reservoir water quality

The flooding of previously forest and agricultural land in the submergence area will increase the availability of nutrients resulting from decomposition of vegetative matter. Phytoplankton productivity can supersaturate the euphotic zone with oxygen before contributing to the accommodation of organic matter in the sediments. Enrichment of impounded water with organic and inorganic nutrients will be the main water quality problem immediately on commencement of the operation. However, this phenomenon is likely to last for a short duration of few years from the filling up of the reservoir. The water quality in the pre-project scenario is quite good. In the post-project phase too, the pollution loading in the reservoir is not expected to increase significantly, hence reservoir water quality is not likely to be adversely affected. Thus, in the proposed project, no significant reduction in D.O. level in reservoir water is anticipated. 11.4.3 IMPACTS ON AIR ENVIRONMENT In a water resources project, air pollution occurs mainly during project construction phase. The major sources of air pollution during construction phase are:

Pollution due to fuel combustion in various equipment Emission from various crushers Fugitive emissions from various sources. Pollution due to increased vehicular movement Dust emissions from muck disposal




i) Pollution due to fuel combustion in various equipment

The operation of various construction equipment requires combustion of fuel. Normally, diesel is used in such equipment. The major pollutant which gets emitted as a result of combustion of diesel is SO2. The SPM emissions are minimal due to low ash content in diesel. The short-term increase in SO2, even assuming that all the equipment are operating at a common point, is quite low, i.e. of the order of less than 1 g/m3. Hence, no major impact is anticipated on this account on ambient air quality. ii) Emissions from crushers

During construction phase, at least one crusher will be commissioned at the quarry site by the contractor involved in construction activities. It is proposed only crushed material would be brought at construction site. The total capacities of the two crushers are likely to be of the order of 120-150 tph. Water is required to wash the boulders and to lower the temperature of the crushing edge. About 0.1 m3 of water is required per ton of material crushed. The effluent from the crusher would contain high-suspended solids. About 12-15 m3/hr of wastewater is expected to be generated from each crusher. The effluent, if disposed without treatment can lead to marginal increase in the turbidity levels in the receiving water bodies. It is proposed to treat the effluent from crushers in settling tank before disposal so as to ameliorate even the marginal impacts likely to accrue on this account. Fugitive Emissions from various sources During construction phase, there will be increased vehicular movement. Lot of construction material like sand, fine aggregate are stored at various sites, during the project construction phase. Normally, due to blowing of winds, especially when the environment is dry, some of the stored material can get entrained in the atmosphere. However, such impacts are visible only in and around the storage sites. The impacts on this account are generally, insignificant in nature. iii) Pollution due to increased vehicular movement

During construction phase, increase in number of vehicles is anticipated for transportation of construction material. The increase in number of vehicles is expected to be a maximum of 20/hour. The impacts on ambient air quality due to increase in vehicular movement is given in Table-11.6.




Table-11.6: Increase in pollutants due to vehicular movement

Distance PM (g/m3) NOx (g/m3) 100 34.73 0.63 150 30.39 0.55 200 27.01 0.49 250 24.31 0.44 300 20.26 0.36 350 16.21 0.29 400 9.72 0.18 450 8.10 0.15 500 7.37 0.13

It can be concluded from Table-11.6, that no major impacts on ambient air quality is anticipated due to increase in a vehicular movement during construction phase. iv) Dust emissions from muck disposal

The loading and unloading of muck is one of the source of dust generation. Since, muck will be mainly in form of small rock pieces, stone, etc., with very little dust particles. Significant amount of dust is not expected to be generated on this account. Thus, adverse impacts due to dust generation during muck disposal are not expected. 11.4.4 IMPACTS ON NOISE ENVIRONMENT a) Construction phase

In a water resource projects, the impacts on ambient noise levels are expected only during the project construction phase, due to earth moving machinery, etc. Likewise, noise due to quarrying, blasting, vehicular movement will have some adverse impacts on the ambient noise levels in the area. i) Impacts due to operation of construction equipment

The noise level due to operation of various construction equipment is given in Table-11.7.




Table-11.7: Noise level due to operation of various construction equipment

Equipment Noise level dB(A) Earth moving Compactors 70-72 Loaders and Excavator 72-82 Dumper 72-92 Tractors 76-92 Scrappers, graders 82-92 Pavers 86-88 Truck 84-94 Material handling Concrete mixers 75-85 Movable cranes 82-84 Stationary Pumps 68-70 Generators 72-82 Compressors 75-85 Others Vibrators 69-81 Saws 74-81

Under the worst-case scenario, considered for prediction of noise levels during construction phase, it has been assumed that all these equipment generate noise from a common point. The increase in noise levels due to operation of various construction equipment is given in Table-11.8.

Table-11.8: Increase in noise levels due to operation of various construction equipment Increase in noise levels due to operation of various construction

equipment

Distance (m) Ambient noise

levels dB(A)

Increase in noise level due to construction activities dB(A)

Increase in ambient noise level due to

construction activities dB(A)

100 36 45 34 200 36 39 29 500 36 31 25 1000 36 25 25 1500 36 21 24




Distance (m) Ambient noise

levels dB(A)

Increase in noise level due to construction activities dB(A)


construction activities dB(A)

2000 36 19 24 2500 36 17 24 3000 36 15 24

It would be worthwhile to mention here that in absence of the data on actual location of various construction equipment, all the equipment have been assumed to operate at a common point. This assumption leads to over-estimation of the increase in noise levels. Also, it is a known fact that there is a reduction in noise level as the sound wave passes through a barrier. The transmission loss values for common construction materials are given in Table-11.9.

Table-11.9: Transmission loss for common construction materials

Material Thickness of construction material (inches)

Decrease in noise level dB(A)

Light concrete 4 38 6 39

Dense concrete 4 40 Concrete block 4 32

6 36 Brick 4 33 Granite 4 40

Thus, the walls of various houses will attenuate at least 30 dB(A) of noise. In addition there are attenuation due to air absorption, rain, atmospheric inhomogeneties and vegetal cover. Thus, no increase in noise levels is anticipated as a result of various activities, during the project construction phase. The noise generated due to blasting is not likely to have any effect on habitations. However, blasting can have adverse impact on wildlife, especially along the alignment of the tunnel portion. It would be worthwhile to mention that no major wildlife is observed in and around the project site. Hence, no significant impact is expected on this account.




Impacts due to increased vehicular movement During construction phase, there will be significant increase in vehicular movement for transportation of construction material. At present, there is no vehicular movement near the dam site. During construction phase, increase in vehicular movement is expected to increase up to a maximum of 20 trucks/hour. As a part of EIA study, impact on noise level due to increased vehicular movement was studied using Federal Highway Administration model. The results of modelling are outlined in Table-11.10.

Table-11.10: Increase in noise levels due to increased vehicular movement Distance

(m) Ambient

noise level dB(A)

Increase in noise level due to increased vehicular

movement dB(A)

Noise levels due to increased

vehicular movement

dB(A)


increased vehicular movement dB(A)

10 40 66 66 26 20 40 61 61 21 50 40 55 55 15

100 40 51 51 11 200 40 46 47 7 500 40 40 43 3 1000 40 36 41 1

As mentioned earlier, there will be significant attenuation due to various factors, e.g. absorption by construction material, air absorption, atmospheric in homogeneties and vegetal cover. Thus, no significant impact on this account is anticipated. Appropriate measures have been suggested as a part of Environmental Management Plan (EMP) report to minimize impacts on wildlife. Impacts on labour The effect of high noise levels on the operating personnel, has to be considered as this may be particularly harmful. It is known that continuous exposures to high noise levels above 90 dB(A) affects the hearing acuity of the workers/operators and hence, should be avoided. To prevent these effects, it has been recommended by Occupational Safety and Health Administration (OSHA) that the exposure period of




affected persons be limited as per the maximum exposure period specified in Table-11.11 .

Table-11.11: Maximum Exposure Periods specified by OSHA Maximum equivalent continuous

Noise level dB(A) Unprotected exposure period per day for 8

hrs/day and 5 days/week 90 8 95 4

100 2 105 1 110 ½ 115 ¼ 120 No exposure permitted at or above this level

11.4.5 IMPACTS ON LAND ENVIRONMENT a) Construction phase

Very few impacts of construction phase are permanent. Majority of the environmental impacts attributed to construction works are temporary in nature, lasting mainly during the construction phase and often little beyond the construction period. However, if these issues are not properly addressed, the impacts can continue even after the construction phase for longer duration. The time required for construction of the project shall be of the order of 5 years. Though, impacts due to construction, are temporary in nature, but may attach significance due to the nature and intensity of the impacts. The major anticipated impacts during the construction phase are as follows: Environmental degradation due to immigration of labour population. Quarrying operations. Operation of construction equipment. Disposal of construction waste Impacts due to construction of roads.




Environmental degradation due to immigration of labour population About 1000 workers and 250 technical staff are likely to work during the peak construction phase in the project area. Thus a total of 1250 persons along with their families will reside in the project area during peak construction phase considering family size as 4, the total population to immigrate in the project area during construction phase shall be of the order of 5000. Separate accommodation and related facilities for workers, service providers and technical staff are to be provided as a part of the project. The congregation of labour force is likely to create problems of sewage disposal, solid waste management and felling of trees for meeting fuel requirements, etc. Quarrying operations The details of construction material requirements are give in Tables-11.12 to 11.15.

Table-11.12: Details of construction material requirement for Upper Dam

S. No. Items Details Quantity Unit 1. Impervious Core Material (Clay) 942873 cum 2. Rock fill material 4293594 cum 3. Course Filter 491242 cum 4. Fine Filter 334002 cum 5. Rip Rap 29118 cum 6. M:15 82790 cum 7. M:20 91791 cum 8. M:25 8400 cum

Table-11.13: Details of construction material requirement for Lower Dam

S. No. Items Details Quantity Unit

1. Impervious Core Material (Clay) 98875 cum

2. Rock fill material 1444075 cum

3. Course Filter 179439 cum

4. Fine Filter 114187 cum

5. Rip Rap 103977 cum

6. M:15 1156 cum




Table-11.14: Details of construction material requirement for Saddle Dam

S. No. Items Details Quantity Unit






M:15 375 cum

The details of borrow areas are given in Table11.15.

Table-11.15: Details of borrow Areas

Borrow Area No.

Location (Lat/Long)

Area ( M2) Effective Depth (M)

Quantity (MCM)

Aerial Distance (M)

1 23ᵒ14’30.71”N, 86ᵒ10’34.49”E

104669.12 8 0.83 200

2 23ᵒ14’23.52”N, 86ᵒ10’36.73”E

69435.67 3 0.21 100

3 23ᵒ13’40.31”N, 86ᵒ9’42.90”E

20628.22 3 0.062 630

4 23ᵒ13’35.072”N, 86ᵒ9’10.12”E

25656.28 3 0.077 300

Total 1.179

*Location of tentative borrows areas marked based on desktop studies.

Five rock quarry sites, one at Lower Dam site near Bhuda village and four quarry sites near Upper Dam both at U/S & D/S) have been identified with a cumulative quantity of 28.824 MCM, which is more than sufficient for the required quantity of Bandu PSP. In this connection, it is to mention that all the proposed quarry sites are within 1-5Km aerial distance from Bandu PSP. Sufficient quantity of natural sand is not available near the vicinity of the project site. If the sufficient quantity of sand is not available from Damodar/ Bokaro/Subarnarekha River beds, it is proposed to use crushed sand from suitable rock available at site. Therefore, crushed manufactured sand of required Fineness Modulus and Grade of the same rock quarry shall be used as sand for the concrete.




A project of this magnitude would require significant amount of construction material. Coarse aggregate would be extracted by quarrying from hills. The quarrying operations are semi-mechanized in nature. Quarrying is normally done by cutting the hill face. A permanent scar is likely to be left, once quarrying activities are over. With the passage of time, rock from the exposed face of the quarry under the action of wind and other erosional forces, get slowly weathered and after some time, they become a potential source of landslide. Thus, it is necessary to implement appropriate slope stabilization measures to prevent the possibility of soil erosion and landslides at the quarry sites. Operation of construction equipment During construction phase, various types of equipment will be brought to the site. These include crushers, batching plant, drillers, earth movers, rock bolters, etc. The siting of these construction equipment would require significant amount of space. In addition, land will also be temporarily acquired, i.e. for the duration of project construction for storage of the quarried material before crushing, crushed material, cement, rubble, etc. Efforts must be made for proper siting of these facilities. Various criteria for selection of these sites would be: Proximity to the site of use. Sensitivity of forests in the nearby areas. Wildlife, if any, in the nearby area Proximity from habitations. Efforts shall be made to select the site for locating the construction equipment in such a way that the adverse impacts on environment are minimal. Efforts must be made to site the construction equipment, so that the residents of nearby villages are not adversely affected. During construction phase, there will be increased vehicular movement for transportation of various construction materials to the project site. Large quantity of dust is likely to be entrained due to the movement of trucks and other heavy vehicles on unpaved road. However, such ground level emissions do not travel for long distances. In addition, there are no major habitations in the project area. Thus, no significant impacts are anticipated on this account.




Disposal of Construction Waste The construction phase would generate significant quantity of waste. As a part of the waste could be utilized as a construction material and levelling of the construction sites. The balance is proposed to be disposed off at designated area. Normally, land is cleared before disposal of waste. During clearing operation trees are cut, but undergrowth perishes as a result of disposal of waste. It is necessary to develop a proper muck disposal plan for amelioration of above referred impacts. Muck disposal Muck generation and disposal could lead to various adverse impacts. The muck needs to be disposed at designated sites. This could lead to following impacts:

loss of land problems regarding stability of spoil dumps access to spoil dump areas

A part of the muck can be used for the following purposes:

use of suitable rock from the excavation as aggregate in the mixing of concrete.

use of muck for maintenance of roads. use of muck in coffer dam. use as backfill material in quarry and borrow pits.

The balance muck shall be disposed at designated sites Muck, if not securely transported and dumped at pre-designated sites, can have serious environmental impacts, such as:

Muck, if not disposed properly, can be washed away into the main Bandu nalla which can cause negative impacts on the aquatic ecosystem of the Bandu nalla.

Muck disposal can lead to impacts on various aspects of environment. Normally, the land is cleared before muck disposal. During clearing operations, trees are cut, and undergrowth perishes as a result of muck disposal.




In many of the sites, muck is stacked without adequate stabilisation measures. In such a scenario, the muck moves along with runoff and creates landslide like situations. Many a times, boulders/large stone pieces enter the Bandu Nalla, affecting the benthic fauna, fisheries and other components of aquatic biota.

Normally muck disposal is done at low lying areas, which get filled up due to stacking of muck. This can sometimes affect the natural drainage pattern of the area leading to accumulation of water or partial flooding of some area which can provide ideal breeding habitat for mosquitoes.

Operation of construction equipment During construction phase, various types of equipment will be brought to the site. These include crushers, batching plant, drillers, earthmovers, rock bolters, etc. The siting of this construction equipment would require significant amount of space. Similarly, space will be required for storing of various other construction equipment. In addition, land will also be temporarily acquired, i.e. for the duration of project construction for storage of quarried material before crushing, crushed material, cement, rubble, etc. Efforts shall be made for proper siting of these facilities. Various criteria for selection of these sites would be: Proximity to the site of use Sensitivity of forests in the nearby areas Proximity from habitations Proximity to drinking water source Efforts must be made to locate equipments in such a way that the adverse impacts on environment are minimal, i.e. to locate the construction equipment, so that impacts on human and faunal population are minimal. Soil erosion The runoff from the construction sites will have a natural tendency to flow towards Bandu Nalla. For some distance downstream of major construction sites, such as upper and lower dam, power house, etc. there is a possibility of increased sediment levels which will lead to reduction in light penetration, which in turn could reduces the photosynthetic activity to some extent of the aquatic plants as it depends directly




on sunlight. This change is likely to have an adverse impact on the primary biological productivity of the affected stretch of Bandu Nalla. However, runoff from construction sites, entering small streams would have significant adverse impact on their water quality. The runoff would increase the turbidity levels with corresponding adverse impacts on photosynthetic action and biological productivity. The impacts on these streams and rivulets thus, would be significant. Adequate measures need to be implemented as a part of EMP to ameliorate this adverse impact to the extent possible. v) Impacts due to roads

The project site is located in Purulia district in the state of West Bengal. Access road networks to Purulia are available from all the major cities in the state. Materials required for project construction such as steel and cement have to be transported from the point of source to the site. Similarly construction equipment and machinery shall also to be brought to the construction site. Additional roads shall be constructed to improve accessibility to the project site. The construction of roads can lead to the following impacts: Removal of trees on slopes and re-working of the slopes in the immediate

vicinity of roads can encourage landslides, erosion gullies, etc. With the removal of vegetal cover, erosive action of water gets pronounced and accelerates the process of soil erosion and formation of deep gullies. Consequently, the hill faces are bared of soil vegetative cover and enormous quantities of soil and rock can move down into water body/river, and in some cases, the road itself may get washed out.

Construction of new roads increases the accessibility of a hitherto undisturbed areas resulting in greater human interferences and subsequent adverse impacts on the ecosystem.

Increased air pollution during construction phase

b) Operation phase The total land required for the project is 397.00 ha. The details are given in Table-11.16.




Table-11.16: Land requirement for proposed project

S. No. Project components Land (Ha) Total (Ha) Forest (Ha) Non-

Forest (Ha)

1 Upper Dam a) Submergence area b) Upper Dam, Saddle Dam

with Spillway

97 35

132

2 Lower Dam a) Submergence area b) Lower Dam & Spillway

101 15

116

3 Water Conductor system a) Head Race Tunnel b) Tail Race Tunnel

3.0 2.0

5.0

4 Power house Couple Powerhouse & Transformer Hall, Switchyard, Mat & other Adits

10

10

5 Penstock Yard 5.0 5.0 6 Project Road 10 10 7 Construction Facilities 10 10 8 Project Office Buildings 2.0 2.0 9 Batching plant, Stock yards &

Site Offices 7.0 7.0

10 Borrow Area 22 22

11 Rock Quarry 60 60 12 Project Colony including

contractors colony 10.0 10.0

13 Muck Disposal 8.0 8.0 Total 387 10.0 397.00

As per the ownership status, about 387 ha of land is forest land and the remaining (10.0 ha) is non-forest land. Appropriate compensation measures as per ownership status has been suggested as a part of the Environmental Management Plan.




11.4.6 IMPACTS ON TERRESTRIAL FLORA a) Construction phase

Increased human interferences The direct impact of construction activity for any water resource project in a mountainous terrain similar to that of proposed project is generally limited in the vicinity of the construction sites only. As mentioned earlier, a large population (4000) including technical staff, workers, and their family members are likely to congregate in the area during peak project construction phase. It can be assumed that the technical staff will be of higher economic status and will live in a more urbanized habitat, and will not use wood as fuel, if adequate alternate sources of fuel are provided. However, workers and other population groups residing in the area may use fuel wood (if no alternate fuel is provided) for whom firewood/coal depot could be provided. * Average fuel wood consumption : 20 kg pcd * Average population size over : 4000 project construction phase * Average consumption per day : 800 quintals/day Or 292000 quintals/year * For a construction period of 5 years : 14600,000 quintals or 182500 m3. * One tree produces about 2.5 m3 of wood, thus, about 73,000 tree will be cut

to meet the fuelwood requirements to the labour population, over a construction phase of 5 years.

Hence to minimize impacts, community kitchens have been recommended. These community kitchens shall use LPG or diesel as fuel. Impacts due to increased human interferences The other major impact on the flora in and around the project area would be due to increased level of human interferences. The workers may also cut trees to meet their requirements for construction of houses and other needs. Thus, if proper measures are not undertaken, adverse impacts on terrestrial flora is anticipated. Since, labour




camps are proposed to be constructed by the contractor along with necessary facilities, such impacts are not envisaged. During construction of various components of the project, e.g., road, colony, dam axis, muck disposal, etc. trees will have to be cleared. The tree felling or clearing shall be done by the State Forest Department. Impacts due to Vehicular movement and blasting Dust is expected to be generated during blasting, vehicle movement for transportation of construction material or construction waste. The dust particles shall settle on the foliage of trees and plants, thereby reduction in amount of sunlight falling on tree foliage. This will reduce the photosynthetic activity. Based on experience in similar settings, the impact is expected to be localized upto a maximum of 50 to 100 m from the source. In addition, the area experiences rainfall for almost 8 to 9 months in a year. Thus, minimal deposition of dust is expected on flora. Thus, no significant impact is expected on this account. Operation phase

Acquisition of forest land The total land required for the project is 397.00 ha, of which 387.00 ha is the would be of forest land. Compensatory afforestation has been recommended. In addition, the project proponent will also pay the NPV of forest and cost of trees, as decided by the Forest Department, as a part of Forestry Clearance. 11.4.7 IMPACTS ON TERRESTRIAL FAUNA a) Construction phase

Disturbance to wildlife The total land required for the project is 397.00 and the area under submergence of Upper and Lower reservoirs is 197 ha. The balance (200 ha) land is required for other project appurtenances. Based on the field studies and interaction with locals, it was confirmed that no major wildlife is reported in the proposed submergence area. It would be worthwhile to




mention here that most of the submergence lies within the gorge portion. Thus, creation of a reservoir due to the proposed project is not expected to cause any significant adverse impact on wildlife movement. The project area and its surroundings are not reported to serve as habitat for wildlife nor do they lie on any known migratory route. Thus, no impacts are anticipated on this account. During the construction period, large number of machinery and construction workers shall be mobilized, which may create disturbance to wildlife population in the vicinity of project area. The operation of various equipments will generate significant noise, especially during blasting which will have adverse impact on fauna of the area. The noise may scare the fauna and force them to migrate to other areas. Likewise siting of construction plants, workshops, stores, labour camps etc. could also lead to adverse impact on fauna of the area. During the construction phase, accessibility to area will lead to influx of workers and the people associated with the allied activities from outside will also increase. Increase in human interference could have an impact on terrestrial ecosystem. The other major impact could be the blasting to be carried out during construction phase. This impact needs to be mitigated by adopting controlled blasting and strict surveillance regime and the same is proposed to be used in the project. This will reduce the noise level and vibrations due to blasting to a great extent. Impacts due to Vehicular movement and blasting Dust is expected to be generated during blasting, vehicle movement for transportation of construction material or construction waste. The dust particles shall settle on the foliage of trees and plants, thereby reduction in amount of sunlight falling on tree foliage. This will reduce the photosynthetic activity. Based on experience in similar settings, the impact is expected to be localized upto a maximum of 50 to 100 m from the source. In addition, the area experiences rainfall for almost 8 to 9 months in a year. Thus, minimal deposition of dust is expected on flora. Thus, no significant impact is expected on this account. Acquisition of forest land During project construction phase, land will be required for location of construction equipment, storage of construction material, muck disposal, widening of existing roads and construction of new project roads. The total land requirement for the project is 397 ha, of which 387 ha in the forest land. No rare and endangered




species are observed in the forest to be acquired for the project. The forest area to be acquired or the project area does not lie on the migratory route of wildlife. b) Operation phase

Impacts on avi-fauna With the damming of Bandu Nalla, two reservoirs with a total area of about 200 ha will be created, with quiescent/tranquil conditions. The reservoir banks will have wet environment throughout the year which can lead to proliferation of vegetation e.g. grass, etc. along the reservoir banks. Such conditions are generally ideal for various kinds of birds, especially, water birds. This is expected to increase the avi-faunal population of the area. Increased accessibility During the project operation phase, the accessibility to the area will improve due to construction of roads, which in turn may increase human interferences leading to marginal adverse impacts on the terrestrial ecosystem. The increased accessibility to the area can lead to increased human interferences in the form of illegal logging, lopping of trees, collection of non-timber forest produce, etc. Since significant wildlife population is not found in the region, adverse impacts of such interferences are likely to be marginal. 11.4.8 AQUATIC ECOLOGY a) Construction phase

During construction phase wastewater mostly from domestic source will be discharged mostly from various camps of workers actively engaged in the project area. The sewage generated from labour camps shall be treated prior to its disposal, so that there are no adverse impacts on quality of the receiving water body. b) Operation phase

Impacts due to damming of Bandu nalla The damming of Bandu nalla for construction of upper reservoir and increase in dam height of lower reservoir will result in creation of two reservoirs with a total




submergence area of about 200 ha. The dam will change the fast flowing nalla to a quiescent lacustrine environment. The creation of a pond will bring about a number of alterations in physical, abiotic and biotic parameters both in upstream and downstream directions of the proposed dam site. The micro and macro benthic biota is likely to be most severely affected as a result of the proposed project. The reduction in flow rate of Bandu nalla, especially during lean period in filling phase is likely to increase turbidity levels downstream of the dam. Further reduction in rate of flow may even create condition of semi-dessication in certain stretches of the Bandu nalla. This would result in loss of fish life by poaching. Hence, it is essential to maintain minimum flow required for well being of fish life till the disposal point of the tail race discharge. 11.4.9 IMPACTS ON SOCIO-ECONOMIC ENVIRONMENT

A project of this magnitude is likely to entail both positive as well as negative impacts on the socio-cultural fabric of the area. During construction and operation phases, a lot of allied activities will mushroom in the project area. Impacts due to influx of labour force During the construction phase a large labour force, including skilled, semi-skilled and un-skilled labour force of the order of about 1250 persons, is expected to immigrate into the project area. It is felt that most of the labour force would come from other parts of the country. However, some of the locals would also be employed to work in the project. The labour force would stay near to the project construction sites. The project will also lead to certain negative impacts. The most important negative impact would be during the construction phase. The labour force that would work in the construction site would settle around the site. They would temporarily reside there. This may lead to filth, in terms of domestic wastewater, human waste, etc. Besides, other deleterious impacts are likely to emerge due to inter-mixing of the local communities with the labour force. Differences in social, cultural and economic conditions among the locals and labour force could also lead to friction between the migrant labour population and the total population. Economic impacts of the project Apart from direct employment, the opportunities for indirect employment will also be




generated which would provide great impetus to the economy of the local area. Various types of business like shops, food-stall, tea stalls, etc. besides a variety of suppliers, traders, transporters will concentrate here and benefit immensely as demand will increase significantly for almost all types of goods and services. The business community as a whole will be benefited. The locals will avail these opportunities arising from the project and increase their income levels. With the increase in the income levels, there will be an improvement in the infrastructure facilities in the area. Impacts due to land acquisition About 397.00 ha of land proposed to be acquired for the proposed Bandu Nalla Pumped Storage Project. No private land is to be acquired. Thus issues related to Resettlement and Rehabilitation are not envisaged in the proposed Bandu nalla Pumped Storage Project. 11.4.10 INCREASED INCIDENCE OF WATER-RELATED DISEASES The construction of reservoirs replaces the riverine ecosystem by a lacustrine ecosystem. The vectors of various diseases breed in shallow water areas not very far from the reservoir margins. The magnitude of breeding sites for mosquitoes and other vectors in the impounded water is in direct proportion to the length of the shoreline. The construction of the two reservoirs would increase the shoreline by many times as compared to the pre-project shoreline of Bandu Nallaunder submergence. Thus, the construction of the proposed reservoir would enhance the potential breeding sites for various diseases vectors. There are chances that incidence of malaria may increase as a result of the construction and operation of the proposed project. In addition to the construction of the reservoir, the following factors too would lead to the increased incidence of malaria in and around the project area:

aggregation of labour. excavation. inadequate facilities in labour camp.

Aggregation of labour About 1250 labourers and technical staff will congregate in the project area during peak construction phase. The total increase in population is expected to be of the




order of 4000. Most of the labour would come from various parts of the country. The labourer would live in dormitories provided by the Contractor. Proper sanitary facilities are generally provided. Hence, a proper surveillance and immunization schedule needs to be developed for the labour population migrating into the project area. Excavations The excavation of earth from borrow pits etc. is one of the major factor for the increase in prevalence of malaria. After excavation of construction material, the depressions are generally left without treatment where water gets collected. These pools of water, then serves as breeding grounds for mosquitoes. However, in the present case, the borrow areas are within the nalla bed, which in any case remain under water. Thus, no additional habitat for mosquito breeding is created due to excavation. The flight of mosquito is generally limited up to 1 to 2 km from the breeding sites. Since, no residential areas are located within 1 km from the reservoir, periphery, increased incidences of malaria are not anticipated. However, labour camps, etc. could be vulnerable to increased incidence of malaria, if proper control measures are not undertaken. 11.5 ENVIRONMENTAL MANAGEMENT PLAN

Based on the environmental baseline conditions and project inputs, the adverse impacts will be identified and a set of measures will be suggested as a part of Environmental Management Plan (EMP) for their amelioration. An outline of various measures suggested as a part of Environmental Management Plan is briefly described in the following sections. 11.5.1 ENVIRONMENTAL MEASURES DURING CONSTRUCTION PHASE

Facilities in labour camps It is recommended that project authorities can compulsorily ask the contractor to make semi-permanent structures for their workers. These structures could be tin sheds. These sheds can have internal compartments allotted to each worker family. The sheds will have electricity and ventilation system, water supply and community latrines.




The water for meeting domestic requirements may be collected from the rivers or streams flowing upstream of the labour camps. Sanitation facilities One community toilet can be provided per 20 persons. The sewage from the community latrines can be treated in a sewage treatment plant before disposal. Solid waste management from labour camps The labour colonies will generate substantial amount of municipal wastes. In view of the condition that might exist in the labour camps most likely the solid wastes will contain majority of vegetable matter followed by paper and glasses. About 4,000 persons are likely to congregate during the construction phases resulting in generation of about 0.84 tonnes of solid waste/day. The solid waste shall be segregated. The bio-degradable component shall be treated through vermi-composting and the non-biodegradable portion shall be disposed by landfill details of solid waste management plan shall be given as a part of the CEIA study. Provision of free fuel During the construction period of the project, there would be around 600 labour and technical staff would be involved in the project construction work. Many families may prefer cooking on their own instead of using community kitchen. In the absence of fuel for cooking, they would resort to tree cutting and using wood as fuel. To avoid such a situation, project proponent shall provide LPG and/ or kerosene available to the labour population migrating into the area during construction phase. The supply of LPG and kerosene can be ensured on regular basis. A local depot can be established through LPG/ kerosene suppliers for supply of the same. 11.5.2 MUCK DISPOSAL

A part of the muck generated, is proposed to be utilized for construction works after crushing it into the coarse and fine aggregates. The balance quantum of muck would have to be disposed. The muck shall be disposed in low-lying areas (preferably over non-forest land). The sites shall then be stabilized by implementing bioengineering treatment measures.




In the hilly area, dumping is done after creating terraces thus usable terraces are developed. The overall idea is to enhance/maintain aesthetic view in the surrounding area of the project in post-construction period and avoid contamination of any land or water resource due to muck disposal. Two muck disposal areas tentatively have been identified in the vicinity of both upper dam & lower dam area, although detail investigations will be carried out during DPR stage. The details of muck disposal area are given in Table 11.17 which is purely tentative location. It will be confirmed based on detail survey during DPR Stage.

Table-11.17 Details of Muck Disposal Area Muck

Disposal Area No.

Location (Lat/Long)

Area ( M2) Height (M) Quantity (MCM)

Aerial Distance

(KM)

1 23º14’1.59”N, 86º9’31.15”E

35571.80 5 0.18 0.5

2 23º14’22.43”N, 86º10’53.25”E

43532.22 7 0.30 1.2

Total 0.48 *Tentative location of muck Disposal

Suitable retaining walls shall be constructed to develop terraces so as to support the muck on vertical slope and for optimum space utilization. Loose muck would be compacted layer wise. The muck disposal area will be developed in a series of terraces of boulder crate wall and masonry wall to protect the area/muck from flood water during monsoons. In-between the terraces, catch water drain will be provided. The terraces of the muck disposal area will be ultimately covered with fertile soil and suitable plants will be planted adopting suitable bio-technological measures. Various activities proposed as a part of the management plan are given as below:

Land acquisition for muck dumping sites Civil works (construction of retaining walls, boulder crate walls etc.) Dumping of muck Levelling of the area, terracing and implementation of various engineering

control measures e.g., boulder, crate wall, masonry wall, catchwater drain. Spreading of soil Application of fertilizers to facilitate vegetation growth over disposal sites.

For stabilization of muck dumping areas following measures of engineering and biological measures have been proposed




Engineering Measures Wire crate wall Boulder crate wall Retaining wall Catch water Drain

Biological Measures

Plantation of suitable tree species and soil binding species Plantation of ornamental plants Barbed wire fencing

11.5.3 RESTORATION PLAN FOR QUARRY SITES

The measures adopted for landscaping of these quarry sites have been described below: i) Measures to be adopted before quarrying

The top soil, wherever, available in the quarry will be removed before starting the quarrying activity or any other surface disturbance. This top soil will be kept separate and stock piled so that it can be reused after quarrying is over for rehabilitation of sites. ii) Measures to be adopted after quarrying

Diversion of run off Effective drainage system will be provided to avoid the infiltration of run-off and surface waters into the ground of quarry sites. Garland drains around quarry site shall be constructed to capture the runoff and divert the same to the nearest natural drain. Filling of depressions Removal of rocks from quarry sites for different construction works will result in the formation of depression and/or craters. These will be filled by the dumping materials consisting of boulders, rock, gravel and soil from nearby plant/working sites.




Construction of retaining walls Retaining walls will be constructed at the filled up depressions of quarry sites to provide necessary support particularly where there are moderately steep slopes. In addition concrete guards, shall be constructed to check the soil erosion of the area. Rocks for landscaping After the quarrying activities are over, these sites will be splattered with the leftovers of rocks and boulders. These boulders and rocks can support the growth of mosses and lichens, which will act as ecological pioneers and initiate the process of succession and colonization. The boulders of moderate size will be used to line the boundary of a path. Laying of the top soil The depressions/craters filled up with rock aggregates will be covered with top soil. Fungal spores naturally present in top soil will aid plant growth and natural plant succession. The top soil will be further enriched by organic manure and Vesicular-arbuscular mycorrhizal (VAM) fungi. This will help in the process of soil reclamation and the early establishment of juvenile seedlings. Re-vegetation The work plan formulated for re-vegetation of the dumping sites through ‘Integrated Biological and Bio-technological Approach’ would be based upon the following parameters:

i) Evaluation of rock material for their physical and chemical properties to assess the nutrient status to support vegetation.

ii) Formulation of appropriate blends of organic waste and soil to enhance the nutrient status of rhizosphere.

iii) Isolation and screening of specialized strains of mycorrhizal fungi, rhizobium, azotobacter and phosphate solubilizers (bio-fertilizers inoculums) suitable for the mined out sites.

iv) Mass culture of plant specific biofertilizer and mycorrhizal fungi to be procured from different institutions/organisations which are engaged in the phyto-remediation activity of degraded areas.




v) Plantation at quarry sites/areas using identified blend and biofertilizer inoculum.

11.5.4 RESTORATION AND LANDSCAPING OF PROJECT SITES

RESTORATION OF CONSTRUCTION SITES Due to various construction activities, natural environment of the project area will be affected. Engineering and biological measures are suggested for the stabilization and beautification of the disturbed area. Following measures should be adopted for the restoration and landscaping of the construction sites. During the construction phase, proper roads and lanes would be provided in the

working area. Open area in working area would be planted with various plant species. Ornamental plants and avenue plantation should be done along the roads and lanes and in open places in the dam area.

Patch plantation may be done at all vacant sites in and around, adits, working areas etc. with plantation in 2-3 or even more rows wherever possible.

Parks and play grounds with all play implements will be developed in the colony areas during the construction phase and at vacant spaces after completion of the work.

Green areas would be developed in front of offices, hospital, officers club, field hostels, guest houses etc. during the construction phase.

After the completion of all the construction activity, the construction sites and other temporary settlements would be removed and area would be covered with the top soil to support the growth of plant species. These plant species which grow first are considered ecological pioneers and would initiate the process of succession and colonization. Areas close to colony and suitable areas will be landscaped to develop children parks, gardens, etc. The maintenance of the area will be done by the project in O&M stage for the life of the project. Rest of the area will be vegetated and restored. 11.5.5 ENVIRONMENTAL MANAGEMENT IN ROAD CONSTRUCTION

Approach roads will have to be constructed as a part of the access to the construction site. The various aspects to be considered while making the project roads are briefly described in the following paragraphs.




Construction Area for clearing shall be kept minimum subject to the technical requirements of

the road. The method of balanced cut and fill formation shall be adopted to avoid large

difference in cut and fill quantities. The cut slopes shall be suitably protected by breast walls, provision of flat stable

slopes, construction of catch water and intercepting drains, treatment of slopes and unstable areas above and underneath the road, etc.

Where rock blasting is involved, controlled blasting techniques shall be adopted to avoid over-shattering of hill faces.

Excavated material should not be thrown haphazardly but dumped duly dressed up in a suitable form at appropriate places where it cannot get easily washed away by rain, and such spoil deposits may be duly trapped or provided with some vegetative cover.

Drainage Drainage of the water from hill slopes and road surface is very important. All

artificial drains shall be linked with the existing natural drainage system. Surface drains shall have gentle slopes. Where falls in levels are to be

negotiated, check dams with silting basins shall be constructed and that soil is not eroded and carried away by high velocity flows.

Location and alignment of culverts should also be so chosen as to avoid severe erosion at outlets and siltation at inlets.

Grassing and Planting Tree felling for road construction/works should be kept bare minimum and strict

control must be exercised in consultation with the Forest Department. Equivalent amount of new trees should be planted as integral part of the project within the available land and if necessary, separate additional land may be acquired for this purpose.

Depending on the availability of land and other resources, afforestation of roadside land should be carried out to a sufficient distance on either side of the road.




11.5.6 COMPENSATION FOR ACQUISITION OF FOREST LAND

The Indian Forest Conservation Act (1980) stipulates:

- if non-forest land is not available, compensatory plantations are to be established on degraded forest lands, which must be twice the forest area affected or lost, and

- if non-forest land is available, compensatory forest are to be raised over an area equivalent to the forest area affected or lost.

The total land required for the project is 397.00 ha, of which 387.00 ha forest land. It is proposed to afforest the double the area, i.e. (387x2) 774 ha, say 774 ha of forest land being acquired for the project. The indigenous species shall be used for afforestation, which shall be selected in consultation with the Forest Department. In addition, the project payment will also pay for the NPV of forest and cost of trees, which is to be finalized by the Forest Department, as a part of Forestry Clearance. 11.5.7 BIODICVERSITY CONSERVATION PLAN

Safeguards during Construction Phase During the construction phase, various adverse impacts on the forests and wildlife are anticipated in the surrounding areas of the proposed project in terms of increased noise levels, land vibrations during controlled blasting, air pollution, etc. To avoid and minimize the negative impacts from these activities project authorities are advised to prepare strict guidelines as follows:

Strict restrictions shall be imposed on the workers at project sites to ensure that they do not harvest any species/produce from the forests and cause any danger or harm to the animals and birds in the wild.

The fuel wood to the labourers shall be provided by the project proponents so that there is no pressure for cutting of trees to meet fuelwood requirements.

The interference of human population would be kept to a minimum in the adjacent forest areas and it would be ensured that the contractors do not set up labour colonies/camps in the vicinity of forests and wilderness areas.

Only well maintained/new equipment that produces lesser noise would be installed at the work sites.




The best way to control the noise is at source. Certain equipment that needs to be placed permanently at one place like generators, etc. would be housed in enclosed structures to cut off the noise.

The heavy equipment like rotating or impacting machines will be mounted on anti-vibration mountings.

Wherever combustion engines are required they will be fitted with silencers.

The traffic (trucks, etc.) used by the project works will be managed to produce a smooth flow instead of a noise producing stop and start flow. Necessary training/orientation will be provided to the traffic operators/drivers. Sounding of loud horns, etc. in the forested areas should be banned.

Project authorities will use water sprinklers on the road to avoid the dust from construction activities.

Measures to improve habitat of avi-fauna Forests are vital for the survival, foraging, breeding and nesting of avifauna. Natural forests provide a variety of food materials to the birds not only in the form of nectar of flowers, fruits, seeds etc. in the trees, shrubs, herbs and grasses but they also contain a large number of insects eaten by birds. In the forests, food is always available for the faunal component. Although most floral species flower during spring through summer but fruit maturation and seed ripening takes place in them throughout the year. Therefore, first strategy of improvement of habitat for birds is avoiding nest predation or brood parasitism through maintenance of large contiguous forest tract. These areas have the ability to support the largest number of forest interior birds and will also be more likely to provide habitat for area sensitive species. It is more practicable to protect the existing forest area rather than creating new forest area. Another measure for habitat improvement for avi-fauna is to be installation of artificial nest boxes in the influence zone and catchment area of the project after consultation with the forest department as well as local NGOs. These nest boxes has been found to be quite beneficial for attracting hole nester birds. The size and capacity of boxes vary from one species to another.




Wildlife Management Plan There is no major wildlife available in the project area, hence there are no migratory routes too are not reported from the project area. However, following measures are recommended as a part of Wildlife Management Plan for mitigation of adverse impacts:

Proper regulation of movement of floating population and settlement of labour camps near forest area

Control and management of forest fires Anti-poaching Measures There are no ecologically sensitive areas around the project sites. However, the forests at the site and in the study area serve as a habitat for wildlife. Due to construction activities and increased human interferences, as a result of immigration of large labour population and their family members, some adverse impacts may take place on wildlife during construction phase; the increased human interferences can have adverse impact on wildlife in and around the project area. It is recommended that check posts are installed along the following sites to prevent anti-poaching activities. In view of this it is recommended that 4 check posts be developed. The location of these check posts could be:

Near Upper dam site Near Lower dam site Near Labour camp-1 Near Labour camp-2

Each check posts will have 4 guards to ensure that poaching does not take place in the area. One range officers will supervise the guards of various check posts. The checkpost shall have appropriate transportation and communication facilities. Other infrastructure, like areas and communities, etc. too shall be provided. Purchase of anti-poaching kits: To capture and translocate wild animals out of human habitations or agricultural lands, various trapping equipments pertaining to anti-poaching activities are needed. In the absence of these the staff faces difficulties and all efforts made on this behalf are futile.




Infrastructure Development: This includes antipoaching huts, rock shelters development and residential quarters for forest guards. For effective monitoring, one watch tower is also proposed to be established at an identified place having high pressure of biotic interference. These basic amenities for the field staff to enable them to do effective patrolling in the areas. Purchase of Survey equipment & Vehicle: In order to improve network and vigilance it is required to procure equipment like V-SAT and to document and develop a database IT infrastructure like laptops, L.C.D. projectors, altimeters, G.P.S., spotoscope, binoculars, video as well as digital still cameras are essential. Purchase of field vehicle will help in increased vigilance. For better communication and purchase of survey equipment an amount of Rs. 1.05 crore million has been earmarked. Construction of Check posts: To improve vigilance for anti-poaching, better protection, enforcement for control grazing practices the construction of control-grazing-cum-anti poaching check posts. Special Protection Measures Since the area of the would be wet land will be quite vast and is not covered or fenced and thus, it is important to take special protection measures for the flora and fauna, specially migratory birds. With the arrival of the wintering birds, the special staff whether on contract basis or the staff deputed temporarily for 5 months from November to March every year, should be deployed for protection of the migratory birds. The staff for protection should be placed in the double fold high tech tents fixed at the strategic points. Feather jackets, warm clothing including woolen inners, woolen caps, search lights, mobile / tech-phones, jumbo boots, rucksack, torches, sleeping bags, folding cots, Tiffin boxes etc should be provided to the staff deployed on the special protection measures. One Veterinary Doctor and pharmacist need to engage for six months with effect from November to March for the protection of the birds. There should be a good arrangement of Medicines required. Improvement of Habitats




With the change in nature of landscape, its aquatic and terrestrial vegetation will change due to global warming, silt deposits in the reservoir etc. there is a great change in the habits of the migratory birds, fishes. The aquatic culture i.e. both floral and faunal environments will changed to the large extent e.g. in the initial years of the reservoir water storage. It needs immense scientific study for the future with reference to the changed behavior. For fish eating birds, the fish culture of the requisite variety may be developed in addition to the income source of the would be fishermen. The other measures recommended for improvement of habitats are:

Fodder and wild fruit plantation for wild animals and for roosting, breeding and hiding cover for migratory birds etc.

Annual bird count of migratory birds in winter by involving locals and bird experts.

Removal of weeds and rehabilitation with local fruit bearing species in gaps. Anti-grazing drive in draw down area to protect the bird breeding areas in

Wetland during the breeding season w.e.f. April to mid July. Removal of plastic waste from draw down area & shores Education and awareness tours/ visits for school children and celebration of

wildlife week Construction of watch towers

11.5.8 GREENBELT DEVELOPMENT

The forest loss due to the reservoir submergence and construction of other project appurtenances shall compensated as a part of compensatory afforestation. However, it is proposed to develop greenbelt around the perimeter of various project appurtenances, selected stretches along reservoir periphery, etc. The main objectives of creating a green belt around a reservoir are to:

Check soil erosion around the reservoir Check landslides and slips around the reservoir Develop the habitat for wildlife particularly avi-fauna

The general consideration involved while developing the greenbelt are:




- Trees growing up to 10 m or above in height with perennial foliage should be planted around various appurtenances of the proposed project.

- Planting of trees should be undertaken in appropriate encircling rows around the project site.

- Generally fast growing species should be planted. - Since, the tree trunk is normally devoid of foliage up to a height of 3 m, it may

be useful to have shrubbery in front of the trees so as to gives coverage to this portion.

The tree plantation will be done at a spacing of 2.5 x 2.5 m. About 1600 trees per ha will be planted. The maintenance of the plantation area will also be done by the project proponent. The treated waste water and the manure generated by composting of solid waste generated for labour camps will be used for the greenbelt development. The species recommended for greenbelt development are given in Table 11.17.

Table-11.17: Species recommended for greenbelt development

Scientific Name Local Name Trees Aegle marmelos Bael Albizia procera Safed Siris Albizzia lebbek Kala siris Altsonia scholaris Saptparni Artocarpus lacucha Dahua Cassia fistula Amaltas Ficus bengalensis Bargad Holoptelea integrifolia Kanju Mallotus philippinensis Kamla Syzygium cumini Jamun Terminalia arjuna Arjun Terminalia bellirica Bahera Terminalia chebula Haritaki Shrubs Abutilon indicum Jhampi Annona squamosa Seethaphal Calotropis gigantean Akand Carissa spinarum Auka Kuli Zizyphus mauritiana Ber




11.5.9 SUSTENANCE OF RIVERINE FISHERIES

a) Release of minimum flow

During filling phase of Upper and lower reservoirs, it adequate environmental flows are not released, then dry segment of Bandu nalla between barrage/dam site and tail race at certain places may have shallow water subjecting the fish to prey by birds and other animals. Such a condition will also enable the poachers to catch fish indiscriminately. It is therefore, recommended to maintain a minimum flow of to ensure survival and propagation of invertebrates and fish. A detailed study shall be conducted to assess the Environmental Flows during filling phase of the reservoir. b) Sustenance of Endemic Fisheries

It is proposed to implement supplementary stocking programmes for the project area. It is proposed to stock the upper and Lower reservoir nalla stretch upstream of upper reservoir intervening nalla stretch and downstream of lower stretch. The stocking can be done annually by the Fisheries Department, State Government of West Bengal. It is proposed to develop a hatchery at a suitable site, finalized by the Forest Department. 11.5.10 HEALTH AND SAFETY PLAN FOR WORKERS

a) Control of Water-Related Diseases

The increase water fringe area provides suitable habitats for the growth of vectors of various diseases and they are likely to increase the incidence of water-related diseases. Malaria could be the major vector-borne disease in the area. The main breeding seasons of the anopheline mosquito (malaria vector) are the months of September and March. The preferred habitat is stagnant or slow moving fresh water open to sunshine or moderate shade. Malaria can be controlled by mosquito control and mosquito proofing measures. Mosquito control measures aim at destroying the habitat and interrupting the life cycle by mechanical or biological or chemical means. The water resources project consists of various components and each requires a set of specific management measures. The anti-malarial operations can be coordinated by various hospitals and Primary Health Centres in the nearby villages in association with the project authorities.




The site selected for habitation of workers should not be in the path of natural drainage. Adequate drainage system to dispose storm water drainage from the labour colonies should be provided. As far as possible opening or degraded forest will be used as camping sites. Adequate vaccination and immunization facilities should be provided for workers at the construction site. The labour camps and resettlement sites should be atleast 2 to 3 km away from a main water body or quarry areas. Workers would be persuaded not to sleep outside their houses especially during the mosquito breeding months of March and September. Proposed Health Facilities at Construction sites and labour camp A first aid post is to be provided at each of major construction sites, so that workers are immediately attended to in case of an injury or accident to refer to Dispensary. This first-aid post will have at least the following facilities:

- First aid box with essential medicines including ORS packets - First aid appliances-splints and dressing materials - Stretcher, wheel chair, etc.

The first aid post can be housed in temporarily erected structure and should be managed by one Health Assistant and assisted by one dresser/first aid attendant. Doctors from the dispensary can attend First Aid post regularly every day at a fixed time. There should be communication to establish link between the local hospital and then first-aid post, so as to enable doctors from hospital to reach the work site in case of an emergency. The first aid post shall have facilities such as fire fighting equipments, one vehicle or ambulance van for effective functioning. Control of Water Pollution during Construction Phase During project construction phase, sufficient measures need to be implemented to ameliorate the problem of water pollution from various sources. The sewage generated from various labour camps should be treated in septic tanks and disposed by discharging into nearest water body. However, efforts shall be made to discharge the treated effluent only in these water bodies, which are not used for meeting domestic water requirements.




The construction activities would require a crusher to crush large lumps of rocks to the requisite size for coarse as well as fine aggregates. The effluent generated from these crushers will have high-suspended solids. The effluent needs to be treated before disposal. Settling tanks of appropriate size for treatment of effluent from various crushers should be provided. During tunneling work ground water flows into the tunnel along with construction water, which is used for various works like drilling, shortcreting, etc. The effluent thus generated in the tunnel contains high suspended solids. Normally, water is collected in the side drains and drained off into the nearest water body without treatment. It is recommended to construct a settling tank of adequate size to settle the suspended impurities. The sludge from the various settling tanks can be collected once in 15 days and disposed at the site designed for disposal of municipal solid wastes from the labour camps. The sludge after drying could also be used as cover material at landfill disposal site. Control of Water Pollution during Operation Phase During project operation phase, due to absence of any large-scale construction activity, the cause and source of water pollution will be much different. Since, only a small number of O&M staff will reside in the area in the well-designed colony of existing PPSP Project Colony with all the infrastructural facilities, water pollution due to disposal of sewage is not anticipated. 11.5.11 AIR POLLUTION CONTROL Control of Emissions Minor air quality impacts will be caused by emissions from construction vehicles, equipment and DG sets, and emissions from transportation traffic. Frequent truck trips will be required during the construction period for removal of excavated material and delivery of select concrete and other equipment and materials. The following measures are recommended to control air pollution:

The contractor will be responsible for maintaining properly functioning construction equipment to minimize exhaust.

Construction equipment and vehicles will be turned off when not used for extended periods of time.

Unnecessary idling of construction vehicles to be prohibited.




Effective traffic management to be undertaken to avoid significant delays in and around the project area.

Road damage caused by sub-project activities will be promptly attended to with proper road repair and maintenance work.

Control of Air Pollution due to DG sets The Central Pollution Control Board (CPCB) has issued emission limits for generators upto 800 KW. The same are outlined in Table-11.18, and are recommended to be followed.

Table-11.18: Emission limits for DG sets prescribed by CPCB

Parameter Emission limits (gm/kwhr) NOx 9.2 HC 1.3 CO 2.5 PM 0.3

Smoke limit* 0.7

* Light absorption coefficient at full load (m-1) The above standards need to be followed by the contractor operating the DG sets. The other measures are recommended as below:

Location of DG sets and other emission generating equipment should be decided keeping in view the predominant wind direction so that emissions do not effect nearby residential areas.

Stack height of DG sets to be kept in accordance with CPCB norms, which prescribes the minimum height of stack to be provided with each generator set to be calculated using the following formula:

H = h+0.2x √KVA H = Total height of stack in metre h = Height of the building in metres where the generator set is installed KVA = Total generator capacity of the set in KVA Dust Control The project authorities will work closely with representatives from the community living in the vicinity of project area to identify areas of concern and to mitigate dust-related impacts effectively (e.g., through direct meetings, utilization of construction




management and inspection program, and/or through the complaint response program). To minimize issues related to the generation of dust during the construction phase of the project, the following measures have been identified:

Identification of construction limits (minimal area required for construction activities).

When practical, excavated spoils will be removed as the contractor proceeds along the length of the activity.

When necessary, stockpiling of excavated material will be covered or staged offsite location with muck being delivered as needed during the course of construction.

Excessive soil on paved areas will be sprayed (wet) and/or swept and unpaved areas will be sprayed and/or mulched. The use of petroleum products or similar products for such activities will be strictly prohibited.

Contractors will be required to cover stockpiled soils and trucks hauling soil, sand, and other loose materials (or require trucks to maintain at least two feet of freeboard).

Contractor shall ensure that there is effective traffic management at site. The number of trucks/vehicles to move at various construction sites to be fixed.

The construction area and vicinity (access roads, and working areas) shall be swept with water sweepers on a daily basis or as necessary to ensure there is no visible dust.

11.5.12 NOISE CONTROL MEASURES Control of noise from construction equipment The contractors will be required to maintain properly functioning equipment and comply with occupational safety and health standards. The construction equipment will be required to use available noise suppression devices and properly maintained mufflers.

vehicles to be equipped with mufflers recommended by the vehicle manufacturer.

staging of construction equipment and unnecessary idling of equipment within noise sensitive areas to be avoided whenever possible.




notification will be given to residents within 100 m of major noise generating activities. The notification will describe the noise abatement measures that will be implemented.

monitoring of noise levels will be conducted during the construction phase of the project. In case of exceeding of pre-determined acceptable noise levels by the machinery will require the contractor(s) to stop work and remedy the situation prior to continuing construction.

Control Noise from DG sets The following Noise Standards for DG sets are recommended for the running of DG sets during the construction:

The maximum permissible sound pressure level for new diesel generator sets with rated capacity up to 1000 KVA shall be 75 dB(A) at 1 m from the enclosure surface.

Noise from the DG set should be controlled by providing an acoustic enclosure or by treating the enclosure acoustically.

The Acoustic Enclosure should be made of CRCA sheets of appropriate thickness and structural/ sheet metal base. The walls of the enclosure should be insulated with fire retardant foam so as to comply with the 75 dBA at 1m sound levels specified by CPCB, Ministry of Environment & Forests.

The acoustic enclosure/acoustic treatment of the room should be designed for minimum 25 dB (A) Insertion Loss or for meeting the ambient noise standards, whichever is on the higher side.

The DG set should also be provided with proper exhaust muffler. Proper efforts to be made to bring down the noise levels due to the DG set,

outside its premises, within the ambient noise requirements by proper siting and control measures.

A proper routine and preventive maintenance procedure for the DG set should be set and followed in consultation with the DG set manufacturer which would help prevent noise levels of the DG set from deteriorating with use.

Control Noise from crushers Based on literature review, noise generated by a crusher is in the range of 79-80 dB(A) at a distance of 250 ft or about 75 m from the crusher. Thus, noise level at a




distance of 2 m from the crusher shall be of the order of 110 dB (A). The exposure to labour operating in such high noise areas shall be restricted upto 30 minutes on a daily basis. Alternatively, the workers need to be provided with ear muffs or plugs, so as to attenuate the noise level near the crusher by atleast 15 dB (A). The exposure to noise level in such a scenario is to be limited up to 4 hours per day. It is known that continuous exposure to noise levels above 90 dB(A) affects the hearing of the workers/operators and hence has to be avoided. Other physiological and psychological effects have also been reported in literature, but the effect on hearing acuity has been specially stressed. To prevent these effects, it has been recommended by international specialist organizations that the exposure period of affected persons be limited as specified in Table-11.19. Table-11.19: Maximum Exposure Periods specified by Occupational Safety and

Health Administration (OSHA)

Maximum equivalent continuous noise level dB(A)

Unprotected exposure period per day for 8 hrs/day and 5 days/week

90 8 95 4 100 2 105 1 110 ½ 115 ¼ 120 No exposure permitted at or above this level

11.6 INFRASTRUCTURE DEVELOPMENT UNDER LOCAL AREA

DEVELOPMENT COMMITTEE (LADC)

A lump-sum budget @ 0.5% of the Project Cost has been earmarked for construction of Infrastructure and Local Area Development Committee works. The activities envisaged are given as below:

Education Facilities Construction of community toilets Strengthening of existing PHSCs/ Health Care Facilities Bus Stops Drinking Water Supply Miscellaneous activities




11.7 ENVIRONMENTAL MONITORING PROGRAMME

The Environmental Impact Assessment is basically an evaluation of future events. It is necessary to continue monitoring certain parameters identified as critical by relevant authorities under an Environmental Monitoring Programme. This would anticipate any environmental problem so as to take effective mitigation measures. An Environmental Monitoring Programme will be formulated for implementation during project construction and operation phases. The cost estimates and equipment necessary for the implementation of this programme shall also be covered as a part of the Comprehensive EIA study. The Environmental Monitoring Programme for implementation during construction and operation phases is given in Tables-11.20 and 11.21 respectively. Table-11.20: Summary of Environmental Monitoring Programme during Project

Construction Phase S. No. Item Parameters Frequency Location

1. Effluent from Sewage Treatment Plant (STP)

pH, BOD, COD, TSS, TDS

Once every month

Before and after treatment from Sewage Treatment plant

2. Water-related diseases

Identification of water related diseases, adequacy of local vector control and curative measure, etc.

Three times a year

Labour camps and colonies

3.

Noise Equivalent noise level (Leq)

Once in three months

At major construction sites.

4. Air quality PM10 SO2 and NO2 Once every season

At major construction sites

Table-11.21: Summary of Environmental Monitoring Programme during Project

Operation Phase S. No. Items Parameters Frequency Location

1. Water pH, Temperature, EC, Turbidity, Total Dissolved Solids, Calcium,

Thrice a year 1 km upstream of dam site

Reservoir




S. No. Items Parameters Frequency Location Magnesium, Total Hardness, Chlorides, Sulphates, Nitrates, DO. COD, BOD, Iron, Zinc, Manganese

area 1, 5 and 10

km downstream of Tail Race discharge

2. Effluent from

Sewage Treatment Plant (STP)

pH, BOD, COD, TSS, TDS

Once every week Before and after treatment from Sewage Treatment Plant (STP)

3. Erosion & Siltation

Soil erosion rates, stability of bank embankment, etc.

Twice a year -

4. Ecology Status of afforestation programmes of green belt development

Once in 2 years -

5. Water-related diseases

Identification of water-related diseases, sites, adequacy of local vector control measures, etc.

Three times a year Villages adjacent to project sites

6. Aquatic ecology

Phytoplanktons, zooplanktons, benthic life, fish composition

Once a year 1 km upstream of dam site

Reservoir area

1, 5 and 10 km downstream of Tail Race discharge

7.

Landuse Landuse pattern using satellite data

Once in a year Catchment area

8. Soil pH, EC, texture, organic matter

Once in a year Catchment area




11.8 COST FOR IMPLEMENTING ENVIRONMENTAL MANAGEMENT PLAN The total amount to be spent for implementation of Environmental Management Plan (EMP) is Rs.11000 lakh or Rs. 110 crore. The details are given in Table-11.22.

Table-11.22: Cost for Implementing Environmental Management Plan

S. No. Item Cost (Rs.

Lakh) 1. Catchment Area Treatment 2400 2. Compensatory Afforestation, & Bio-diversity

Conservation 3400

3. Fisheries Management 1600 4. Greenbelt development 50 5. Water, Air & Noise pollution control 100 6. Environmental Management in labour camps 700 7. Public health delivery system 300 8. Muck management 1232 9. Restoration, Stabilization and Landscaping of Quarry

sites 200

10. Restoration and Landscaping of construction sites 40 11. Environmental management in road construction 330 12. Energy Conservation measures 200 13. Disaster Management Plan 60 14. Local Area Development Plan 18 15. Environmental Monitoring during construction

Phase 180

16. Other Measures 190 Total 11000, say Rs.

110 crore

CONSTRUCTION MATERIAL

CHAPTER- 09

Chapter –12: Construction Material 1

Bandu Pumped Storage Project, (4x 225 MW)


12.1 General

Bandu Nala Pumped Storage Project envisages the construction of 71 m high upper Rock fill & 25 m high saddle dam with central impervious core located at higher reaches and 53m high lower Rock fill dam with central impervious core located at lower reaches on river Bandu near Ayodhya village, Purulia. The installed capacity shall be 900 MW.

A 71 metre high Rock fill upper dam with central impervious clay core across river Bandu to provide a live storage of 13.49 million cum with Full Reservoir Level at 480.00 metre and Minimum Draw Down Level at 460.83 metre.

A 53 metre high Rock fill lower dam with central impervious clay core across river Bandu to provide a live storage of 13.49 million cum with Full Reservoir Level at 340.44 metre and Minimum Draw down Level at 325.00 metre.

An underground power house with four numbers Francis type reversible pump-turbine of capacity 225/256 MW.

An underground Transformer cavern with four numbers Power Transformer of capacity 280 MVA.

One 400 kV Gas insulated Switchgear. 1687 metre long headrace and tailrace tunnel for conveyance of water.

12.2 Estimated Quantities of Construction Materials A) Upper Dam

Sl. No. Items Details Quantity Unit

1. Impervious Core Material (Clay) 942873 cum 2. Rock fill material 4293594 cum 3. Course Filter 491242 cum 4. Fine Filter 334002 cum 5. Rip Rap 29118 cum 6. M:15 82790 cum 7. M:20 91791 cum 8. M:25 8400 cum

Chapter – 09

Construction Material




B) Lower dam







6. M:15 1156 cum

C) Saddle Dam







M:15 375 cum

12.3 Geo-technical Investigations in vicinity

The Bandu Nala Pumped Storage Project having advantage of easy approach from earlier Purulia Pumped Storage Project & Turga Pumped Storage Project sites. Detailed investigations & estimation for available quantity for construction material will be carried out in DPR stage. Sufficient quantities of construction materials are required for various components i.e. Dam (Upper &lower), Power House, HRT, TRT, Spillways and other appurtenant structures. It is, however essential to carryout detailed investigations for construction materials i.e. rock fill and soil materials for Rock fill dam, coarse and fine aggregates for concrete etc. available near to the project site to assess the suitability in adequacy at Detailed Project Report level.

The main objective of geotechnical investigations is to know the engineering properties of soil, coarse and fine aggregates, Rock fill materials etc. so as to arrive at safe and economical design parameters for civil engineering structures. Both in-situ tests and laboratory tests of the material as per BIS codal provisions are to be undertaken to determine the engineering/physical properties.




12.4 Construction Materials

12.4.1 Rock fill and Coarse Aggregate Material

The project area lies in the NE part of the Ayodhya hills where hard, competent quartzo-feldspathic gneiss are well exposed in the area (Fig.1). In this connection, it is to mention that there are two projects sites (PPSP & TPSP) adjacent to the Bandu nala project site, which has already been tested by CSMRS, New Delhi.

Fig 1: Google earth image showing proposed rock quarry sites for Bandu PSP

As the project area lies on more or less same geological terrain, there will be no difficulty in accepting the geology of the Purulia Pumped Storage Project & Turga Pumped Storage Project.The coarse aggregates required for the concrete can also be available from the quarries in the area (Marked in the layout plan) . Excavated muck from the waterway and power house complex may be used as coarse aggregate for concrete if found suitable. Five rock quarry sites (Fig.2 a to d; one at Lower Dam site near Bhuda village & four quarry sites near Upper Dam both at U/S & D/S) have been identified with a cumulative quantity of 28.824 MCM, which is more than sufficient for the required quantity of Bandu PSP. In this connection, it is to mention that all the proposed quarry sites are within 1-5Km aerial distance from Bandu PSP.




Fig. 2: Photographs showing hard, competent quartz-feldspathic gneiss at lower dam (a), nala bed (b), upstream of upper dam (c & d).

The detail of rockfill materials from different quarry sites is listed below: Quarry

No. **Location (Lat/Long)

Area ( M2) Effective Height (M)

Quantity (MCM)

Aerial Distance

(Km) 1 23ᵒ15’9.16”N,

86ᵒ11’23.15”E 344153.13 70 24.09 2.4

2 23ᵒ14’38.06”N, 86ᵒ8’14.97”E

70889.36 40 2.83 2.12

3 23ᵒ13’46.92”N, 86ᵒ09’55.19”E

3929.04 10 0.039 0.9

4 23ᵒ14’0.97”N, 86ᵒ8’22.29’E

24396.02 15 0.365 1.38

5 23ᵒ14’29.28”N, 86ᵒ8’45.09”E

60082.44 25 1.50 1.22

Total 50.35 Ha 28.824 MCM

** All these locations are tentative and finalized during DPR stage investigations

a b

c d




However, it is proposed to carryout detailed survey and investigations (lab tests) to identify the suitable rock for Rock fill as well as coarse aggregate near the project site at later stages. In this connection it is to mention that the finalization of available quantity of materials have been finalized during further investigation in DPR stage. A number of samples from each of the quarry sites will be collected and tested in the standard laboratory for assessing their suitability for use as Rock fill as well as coarse aggregate in concrete for the construction of various structures. The under mentioned laboratory tests to be carried out as per IS: 2386 (respective sections) at the DPR stage.

Specific Gravity

Water Absorption Aggregate Impact Value

Aggregate Crushing Value

Aggregate Abrasion Value Soundness loss, 5 cycles in Na2So4 solution

Alkali – Aggregate reactivity (Accelerated Martar bar) test

Petrographic Examination

In addition to above laboratory tests the under mentioned tests for Rock fill materials are also to be carried out:

Relative Density test

Large size Tri-axial shear tests with all required parameters

Large size Oedometer test with all required parameters including Permeability test at different stress levels.

Pre and Post grain size distribution for determination of Particle Breakage

12.4.2 Fine Aggregate Material

Sufficient quantity of natural sand is not available near the vicinity of the project site. If the sufficient quantity of sand is not available from Damodar/ Bokaro/Subarnarekha River beds, it is proposed to use crushed sand from suitable rock available at site.

Therefore, crushed manufactured sand of required Fineness Modulus and Grade of the same rock quarry shall be used as sand for the concrete.

The under mentioned laboratory tests are to be conducted as per IS: 2386 during the DPR stage.

Gradation and Fineness modulus Specific Gravity

Silt and Clay content

Organic Impurities




Soundness loss, 5 cycle in Na2So4 solution

Alkali – Aggregate reactivity (Accelerated Mortar bar) test

Petrographic studies

12.4.3 Impervious\ Core material

On the left bank of Bandu Nala in lower dam site, bad land is present, where brown soil over 10-12m(appx.) thick has been observed. Four borrow areas have been identified with a cumulative quantity of 1.179MCM, which is sufficient for the required quantity. These and the adjoining borrow areas of the project site require detailed examination with test pits in a grid pattern and for collection of soil samples from these pits to assess the quality and quantity of soil available for use in construction of core of the dams.

The details of Borrow areas are listed below:

Borrow Area No.

**Location (Lat/Long)

Area ( M2) Effective Depth (M)

Quantity (MCM)

Aerial Distance (M)

1 23ᵒ14’30.71”N, 86ᵒ10’34.49”E

104669.12 8 0.83 200

2 23ᵒ14’23.52”N, 86ᵒ10’36.73”E

69435.67 3 0.21 100

3 23ᵒ13’40.31”N, 86ᵒ9’42.90”E

20628.22 3 0.062 630

4 23ᵒ13’35.072”N, 86ᵒ9’10.12”E

25656.28 3 0.077 300

Total 22.03Ha 1.179

** All these locations are tentative and finalized during DPR stage investigations

However, the finalization of effective quantity of available clay material & suitable borrow areas will be carried out during DPR stage investigations. The under mentioned laboratory tests are to be conducted on the collected samples from the trial pits in accordance with the relevant sections of BIS 2720 codes before the DPR stage.

Moisture content

Specific gravity

Mechanical analysis Atterberg limits & soil classification

Standard Proctor compaction

One dimensional consolidation Triaxial shear

Laboratory Permeability

Soil dispersivity identification tests.




12.4.4 Water Samples

Samples of water are to be collected from Bandu Nala and tested for their suitability for use in construction purposes. All the under mentioned tests on water samples are to be conducted during pre-monsoon, monsoon and post-monsoon periods.

In-situ water quality tests o pH o Conductivity o Temperature o pH – calcium carbonate saturated o Ammonium ions o Deleterions sulphate

Laboratory water quality tests

o Calcium o Magnesium o Sodium cat-ions o Potassium

o Hydroxide o Carbonate o Bi-carbonate An-ions o Chloride o Sulphate o Acidity as CaCo3 o Alkalinity as CaCo3 o Dissolved salts – in organic,

organic and total soluble salts o Suspended solids

12.5 Conclusions

12.5.1 Rock as Coarse aggregate or Rock fill

Sufficient quantity of rock is to be investigated in detail at the DPR stage from open excavation from rock quarries near the project site as well as muck excavation from tunnels etc. There rocks should, however be tested as mentioned under para 9.4.1 for assessing their suitability for use as coarse aggregate in concrete as well as for Rock fill at DPR stage. However, it is to mention that the rocks near Lower & upper dam quarry sites may be used as the quantity of the materials available is enough against the required quantity. The locations of quarry area are tentative which will be finalised during DPR Stage.




12.5.2 Sand as fine aggregate

Sufficient quantity of natural sand is not available near the vicinity of the project site. Therefore, crushed manufactured sand of required Fineness Modulus and Grade of the same rock quarry shall be used as sand in the concrete works.

12.5.3 Soil as Impervious material

Sufficient quantity of soils from trial pits are to be investigated from the borrow areas located in nearby areas. These soil samples should, however be tested as mentioned under para 9.4.3 for assessing their suitability for use in the construction of core of rock fill dams during DPR stage. The natural moisture content of the borrow area material near Bandu PSP sites at the time of investigations maybe found out. The PFR stage borrow area locations are tentative which shall be confirmed during DPR stage.

12.5.4 Water Samples

Samples of water from Bandu Nala or any other suitable sources may be tested for their suitability for use in construction purposes during pre-monsoon, monsoon and post-monsoon periods at the DPR stage. All the tests mentioned under para 9.4.4 should be tested.

ECONOMIC EVALUATION

CHAPTER- 10

Chapter – 13: Economic Evaluation 1



13.1 General

The economic and financial evaluation of Bandu Pumped Storage Project,

West Bengal has been considered as per the standard guidelines issued by

Central Electricity Authority and the norms laid down by the Central Electricity

Regulatory Commission (CERC) for Hydro projects have been kept in view in

this regard.

13.2 Project Benefits

The scheme would afford on annual peaking period energy generation of

1642.50 GWh annually. For assessing the tariff, design energy generation of

1560.38 GWh, calculated with 95% capacity availability in a normal

dependable year, has been adopted. The project would provide 900 MW of 5

hours daily peaking capacity benefits.

13.3 Capital Cost

Three options have been considered.

i) Option-I – All 4 units Fixed type

The project cost has been estimated at Rs. 3809.88 crores without IDC as given below:

1. Cost of civil works = Rs. 2032.11crores 2. Cost of Electrical/Mechanical works = Rs. 1687.77crores

3. Cost of Transmission line = Rs. 90crores

Total = Rs. 3809.88 crores

The project cost excluding land cost has been estimated at Rs.3784.88 crores without IDC as given below:

1. Cost of civil works = Rs. 2007.11crores 2. Cost of Electrical/Mechanical works = Rs. 1687.77 crores



The IDC as estimated based on the phasing of expenditure is Rs.

461.42crores and considering the impact of IDC the estimated project cost will

be Rs. 4271.30 crores(including the land cost).

CHAPTER-10

ECONOMIC EVALUATION




ii) Option-II –2 Units Variable type and 2 units Fixed type

The project cost has been estimated at Rs. 4168.82crores without IDC as given below:



Total = Rs. 4168.82crores

The project excluding land cost has been estimated at Rs. 4143.82crores without IDC as given below:




The IDC as estimated based on the phasing of expenditure is Rs. 487.12crores and considering the impact of IDC the estimated project cost will be Rs. 4655.94 crores (including the land cost).

13.4 Mode of Financing

The project is proposed to be financed with a debt equity ratio of 70:30. An

interest rate of 12.2% on the loan component has been considered for the

financial analysis of the project. The interest on the working capital is taken

as 12.2%.

13.5 Phasing of Expenditure

The project is scheduled to be completed in 5 years 3 months from the

financial closure in all respects. The phasing of the expenditure worked out on

the basis of proposed construction programme is summarized in Table 13.1.




Table – 13.1

Option-I ( 4F) Phasing of Expenditure

Year Capital Expenditure

(Rs. crores)

Up-to 1st Year 101.606

2nd Year 450.866

3rd Year 831.854

4th Year 1174.691

5th Year 977.839

6th Year 273.024

Total 3809.88

Option-2 ( 2V+2F) Phasing of Expenditure

Year Capital Expenditure

(Rs. crores)

Up-to 1st Year 101.847

2nd Year 460.683

3rd Year 877.565

4th Year 1308.691

5th Year 1102.624

6th Year 317.410

Total 4168.82

13.6 Financial Analysis

13.6.1 Basic and Normative Parameters

The following normative parameters have been adopted for working out the

financial analysis of the project including the land cost.

i. For option-1 all fixed type units the estimated capital cost of Rs.

4271.30 crores including the Interest during Construction as Rs.

461.42 crores.




ii. For option-2 all 2 variable and 2 fixed type units the estimated capital

cost of Rs. Rs. 4655.94crores including the Interest during

Construction as Rs. 487.12 crores.

iii. Annual gross energy generation of 1642.50 GWh and annual design

energy as 1560.50 MU.

iv. Operation & maintenance expenses (including insurance) @ 2.5% of

the project cost in the first year with 6.64% escalation every year.

v. Depreciation allowed @ 5.28 % of the project cost excluding land cost

for first 12 years and remaining depreciation is spread over the balance

life i.e. 23 years on an average basis keeping 10% salvage value of the

assets.

vi. Auxiliary consumption i.e. quantum of energy consumed by auxiliary

equipments of the generating station and transformer loss @ 1.25 % of

the energy generated.

vii. Interest on working capital @ 12.20%.

viii. Interest during construction has been worked out based upon the

interest rates @ 12.20 %. The computations are given in Annexure-1

for present day capital cost.

ix. Return on equity @ 15.50%.

x. Pump-Generation Cycle efficiency @ 76.90%

xi. Pumping Energy Required 2344 MU

xii. MAT @ 21.34 %




13.6.2 ASSESSMENT OF TARIFF

Based upon the parameters given above, the sale rate of energy at bus bar has been

computed in Annexure-I. The sale rate applicable in the first year and levellised

tariff is indicated below.


Sl. No. Off Peak Energy Rate

(Rs/kWh)

First Tariff

(Rs/kWh)

Levelized Tariff

(Rs/kWh)

1 1 7.54 6.86

2 2 8.89 8.20

3 3 10.23 9.55



(Rs/kWh)

First Tariff

(Rs/kWh)

Levelized Tariff

(Rs/kWh)

1 1 8.11 7.36

2 2 9.45 8.70

3 3 10.79 10.05

Based upon the parameters given above the levelised cost of energy (i.e. cost

to company) applicable in the first year and levelised year is indicated below

which is also calculated in Annexure-II.



(Rs/kWh)

First Cost (Rs/kWh) Levelized Cost

(Rs/kWh)

1 1 5.87 5.08

2 2 7.22 6.43

3 3 8.56 7.77



(Rs/kWh)

First Cost (Rs/kWh) Levelized Cost

(Rs/kWh)

1 1 6.28 5.42

2 2 7.63 6.77

3 3 8.97 8.11

POWER EVACUATION ARRANGEMENT

CHAPTER- 11

Power Evacuation Arrangement 1



Power Evacuation Arrangement

14.1 Introduction The Bandu Pumped Storage Scheme is located in Purulia district of West Bengal. The Scheme envisages utilization of water of Bandu nala in Ajodha hills for peak power generation in the system. The project envisages installation of 900 MW (4x225 MW) generation for five hours in a day for 355 days in a year (10 days considered for maintenance purpose) and would provide an annual energy generation of 1600 Million units (approx.). 14.2 Existing Power Scenario of West Bengal The present total installed generation capacity in the state is in the tune of about 10382.70 MW out of which the coal fired power stations capacity belongs to about 8543.83 MW, Hydro capacity of about 1417.3 MW, which includes Pump storage and the details are given in below. The future power map of West Bengal is as shown below. Table 14.1 – Installed Capacity of Power Utilities in West Bengal in MW

INSTALLED CAPACITY (IN MW) OF POWER UTILITIES IN THE WEST BENGAL INCLUDING ALLOCATED SHARES IN JOINT & CENTRAL SECTOR UTILITIES

State Ownership/

Sector

Mode wise Breakup Thermal

Nuclear Hydro

(Renewable) RES

(MNRE) Grand Total Coal Gas Diesel Total

West Bengal

State 5740.00 100.00 0.00 5840.00 0.00 986.00 91.95 6917.95

Private 1781.38 0.00 0.00 1781.38 0.00 0.00 329.62 2111.00

Central 922.45 0.00 0.00 922.45 0.00 431.30 0.00 1353.75

Sub -Total 8443.83 100.00 0.00 8543.83 0.00 1417.30 421.57 10382.70

DVC

State 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Private 1050.00 0.00 0.00 1050.00 0.00 0.00 0.00 1050.00

Central 6950.66 0.00 0.00 6950.66 0.00 193.26 0.00 7143.92

Sub -Total 8000.66 0.00 0.00 8000.66 0.00 193.26 0.00 8193.92

Source: CEA 14.3 Power Evacuation Arrangement For evacuation & receiving of power of Bandu Project, one double circuit 400kV Quad Moose / Twin HTLS Transmission line is proposed to be

11 Chapter –

Power Evacuation Arrangement 2



constructed between Bandu Pumped Storage project and 1000 MW Turga Pump Storage project (Proposed). Another same type of Transmission line is proposed to be constructed between Bandu Pumped Storage Project and New Purulia Pumped Storage Project 400 kV GIS beside Bagmundi 132/33 kV Substation.

Table 14.2 - Total Installed Capacity in Eastern Region

Sl. No. Transmission Line Route Length 1. One 400kV D/C to Turga PSP (1000 MW) 15 km

2. One 400kV D/C to 400kV New Purulia PSP GIS. 25 Km

However, a comprehensive load flow study is necessary during DPR stage under peak demand load scenario and pumping power requirement during lean hours encompassing the three pumped storage scheme (PPSP, PPSP extension Project (Turga) & Bandu PSP and thereby setting up Substation & Transmission system effectively.

Source: WBSETCL

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