Ref No: OTPC:EC:2020:001 9th May 2020

Director (lA),Ministry of Environment, Forests and Climate ChangeIndira Paryavaran Bhawan,Jor Bagh Road,New Delhi – 110003

Kind Attention: Dr. S. Kerketta

Sub: Environmental Clearance for Proposed Expansion of Gas Based Combined Cycle Power Plant at Palatana Village in Udaipur, TripuraRef: F.No. J-13012/02/2017-IA. II (T) Online No. IA/TR/THE/97559/2006

Dear Sir,

With reference to above, kindly find enclosed additional information requested for grant of Environmental Clearance for Proposed Expansion of Gas Based Combined Cycle Power Plant at Palatana village in Udaipur District, Tripura.

We hope your will find the enclosed documents in order. Kindly let us know in case any additional document or information is required. We now look forward to receive Environmental Clearance for proposed Palatana Power Plant Expansion Project.

Thanking You

Yours sincerelyfor ONGC TRIPURA POWER COMPANY LIMITED

SATYAJIT GANGULYMANAGING DIRECTOR

Encl: as above

Additional Information Details for Environmental Clearance of OTPC Expansion Project

1. In case 15% increase of installed capacity of the proposed existing plant to be made then necessary amendment of the ToR to be taken up.

OTPC Response:

The capacity mentioned in the approved ToR (J-13012/02/2017-IA.I(T) dated 06.04.2017) is 726.6 MW (Unit 3 & 4: 2 x 363.3 MW). However, in the EIA Report and EAC presentation, we have proposed the capacity of the plant will be (2 x 363.3 MW) + 15%. We have reviewed the specifications with our project design team and would not require additional 15% installed capacity. The proposed capacity will remain as per approved ToR, with capacity of proposed unit being 363.3 MW.

2. Confirmation on the availability of natural gas of 2.7 MMSCMD for proposed project to be obtained from M/s. ONGC.

OTPC Response: MoPNG has allocated 5.0 MMSCMD natural gas to OTPC Power Project (L-12013/12/04-GP dated 7 October 2004). Out of 5 MMSCMD gas 2.65 MMSCMD is being used for existing units (Unit 1 & 2) and 2.35 MMSCMD is available for further expansion of the existing plant. The average annual consumption of the gas for new units will be (considering 85% PLF) 987 to 1204 MMSCM per unit. Average daily estimated gas requirement at site ambient condition is estimated to be 2.70 to 3.30 MMSCMD. OTPC has requested MoPNG for allocation of additional gas for meeting the shortfall. However, till date we have not received any additional gas allocation from MoPNG.

Currently, 2.35 MMSCMD of pre-allocated gas stream is available for the proposed expansion, which would be sufficient for one unit (1 x 263.3 MW). Therefore, we like to propose that the EAC considers providing us EC for the 3rd unit (1 x 363.3 MW). Subsequently, when MOPNG will allocate additional gas, OTPC will inform MoEF&CC for further amendment of EC for Unit 4 (1 x 363.3 MW) or apply for fresh expansion EC.

3. The wildlife conservation plan for Schedule-I species vetted by the Chief Wildlife Warden to be submitted.

OTPC Response: The wildlife conservation plan for Schedule-I species has already been submitted to Chief Wildlife Warden, Tripura for approval. Submitted letter has been attached (Appendix-2).

4. NBWL recommendations from wildlife angle for the existing plant to be obtained

OTPC Response:

The Environmental Clearance (EC) for the existing project was accorded by MoEF&CC in February 2007 and the validity of the same was subsequently extended to May 2012 (vide Letter No. J 13011/11/2006-IA.II (T) dated 07.02.2007 & dated 03.05.2012). The requirement of getting NBWL recommendation was not provided in the EC letter(s).

In addition, OTPC submits periodical compliance reports to Regional Office of MoEF&CC. Representatives of Regional Office of MoEF&CC have periodically visited the plant for verification of EC conditions/compliance. The above requirement had not been recommended so far. In view of the above, no application was made earlier to the NBWL for the existing project.

Furthermore, as informed by OTPC during the appraisal meeting held on 26 April 2019, the draft notification for declaring Eco-Sensitive Zone around the Trishna Wildlife Sanctuary had already been published in Sept, 2018 (vide S.O. 4776 (E), dated 10 September 2018) with 0 to 500 m wide ESZ around the boundary of the Sanctuary. The minimum distance of Trishna Wildlife Sanctuary from the plant is 7.74 km.

OTPC has already prepared Wildlife Conservation Plan for Schedule I species and same has been submitted to Chief Wildlife Warden, Tripura, for approval. OTPC will comply the conditions given by the Chief Wildlife Warden, Tripura in this regard.

5. The existing power plant is discharging the treated effluent water (approximately 4,858

m3/day) into the Gomti river. Therefore, it is mandated to convert the entire water treatment system into zero discharge system for both existing and proposed power project

OTPC Response:

For conservation of both existing and proposed units into zero discharge, RO treatment systems for treated effluent from existing units is also to be implemented in addition to that proposed for expansion project. It is proposed to take-up the above work as part of expansion project as there would be implications both capital/ operational cost and budgetary approval for the same would be required from necessary authorities. The achievement of zero discharge for the entire plant will be aligned with COD (Commercial Operation Date) of expansion Unit of the plant. With the implementation of the above, after COD of expansion unit, the additional water requirement for the expansion unit will be reduced to 16,539 m3/day. About 7608 m3/day RO treated water will be utilised as cooling makeup water for expansion units and the entire balance treated water will be used for greenbelt & Horticulture with zero discharge outside the plant premises. The specific water consumption for proposed expansion project would be reduced to 0.98 m3/MWh against the limit of 2.5 m3/MWh.

The details of water utilization plan for (i) existing unit, (ii) proposed expansion unit with zero discharge, (iii) zero discharge for both existing and proposed project has been presented below.

S No. Units Existing (m³/day)

Proposed Expansion unit (m³/day)- zero discharge for proposed units only

Proposed Expansion unit (m³/day)- zero discharge for existing and proposed units

1. CW Make-up 23712 24,000 24000

2. DM Water Make-up to HRSG Cycle 864 Existing Plant Existing Plant

3. Evaporation Loss 64 48 27

4. Plant Service Water System 240 Existing Plant Existing Plant

5. Plant Potable Water System 240 Existing Plant Existing Plant

6. Expected Sludge in the River Water to Plant

200 504 120

7. Recovery water from Blow down of RO Plant

- (-) 3792 (-) 7608

Total Fresh Water Requirement 25320 20400 16539

6. Isolated open area within the project to be earmarked and taken up for plantation.

OTPC Response:

Total plant site area is 197.15 acre i.e. 79.78 ha. (Existing and Proposed expansion units). OTPC has also acquired 8.24 acres (3.33 ha) for raw water pipeline corridor & 2.21 acres (0.89 ha) for plant site boundary straightening purposes. Hence total Project area including raw water pipeline corridor is 207.60 Acres. Green belt area developed under the project: 73.08 Acres. The percentage of greenbelt area developed with respect to total project area (proposed& expansion) : 35.20% of the plant area.

However, as suggested by the EAC, the isolated open area within the project will be utilised for plantation.

7. To isolate the gas handling plant during emergency, water sprinkler jacket be provided for

both existing and proposed plants

OTPC Response:

To isolate the gas handling plant during emergency, water sprinkler jacket will be provided for both existing and proposed plants.

Appendix -1 Copy of the 5.0 MMSCMD natural gas allocation letter to OTPC from MoPNG, Govt. of India and Fuel Supply Agreement with ONGC

Appendix-2: Wildlife Conservation Plan Submission Letter