SPECN. NO.: PE-TS N001 Vol-IIB (Book 2 of 2) & (Book 1 of 2) TECHNICAL SPECIFICATIONS COOLING TOWERS REV. NO. 0 DATE: AMENDMENT NO.

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1 TECHNICAL SPECIFICATIONS COOLING TOWERS SPECN. NO.: PE-TS N001 Vol-IIB (Book 2 of 2) & (Book 1 of 2) AMENDMENT NO. 2 REV. NO. 0 DATE: With reference to Section-C, sub-section-3 (Geo-technical investigation), Vol-IIB (Book 2 of 2), (pages 109 to 114 of pdf file) of Technical Specification, please consider the Specification amended as below: Clause as mentioned in Technical Specification Amended Clause Sub-section-3 (Geo-technical investigation)-pages 109 to 114 (of pdf file). Complete sub-section-3 shall be replaced as enclosed with this amendment No With reference to Clause (c) Section-C1, Volume IIB (Book 1 of 2) of Technical Specification, please consider the Specification amended as below: Clause as mentioned in Technical Specification Amended Clause 18 mm for pipe size for 2100 NB. 16 mm for pipe size for 2000 NB. 3.0 With reference to Clause 10.0, Data sheet-a, Section-C1, Volume IIB (Book 1 of 2) of Technical Specification, please consider the Specification amended as below: Clause as mentioned in Technical Specification Amended Clause Hot Water Supply Header: CW return piping.(2100 NB). Hot Water Supply Header: CW return piping.(2000 NB).

2 1x370MW CCPP,YELAHANKA SPECIFIC TECHNICAL REQUIREMENTS SPECIFICATION NO. VOLUME II B SECTION - C SUB-SECTION - REV.01 DATE SHEET 1 OF GEO-TECHNICAL INVESTIGATION & FOUNDATION SYSTEM BHEL had carried out detailed geo-technical investigation in the proposed cooling tower site. The sub-strata details encountered at various bore holes (BH-22, 32 & BH-CT) in the cooling tower area are enclosed as Annexure-1 The geotechnical data attached shall be solely for the purpose of guidance to the bidder. BHEL/owner does not take any responsibility about the accuracy and applicability of the geo-technical data furnished herewith. The onus of correct assessment/interpretation and understanding of the existing sub-strata conditions is on the bidder. Any variation in the data between the one furnished and to that found during execution of the work at site shall not constitute a valid reason in affecting the terms & conditions of this bid and the bidder shall note that nothing extra will be payable on this account. The bidder shall fully satisfy himself about the nature of sub-strata expected to be encountered including the type of foundation, ground water table and construction methodology to be adopted etc prior to the submission of the bid Detailed geo-technical Investigation report shall be made available to the successful bidder during contract engineering stage. If the bidder desires to carry out additional geo-technical investigation he/she may do so with prior information/permission of BHEL/owner at no extra cost to BHEL/owner. No extension in time schedule shall be permitted on this account. The bidder shall obtain approval on the agency for conducting geo-technical investigation work, field and laboratory testing schedule proposed by the bidder etc from BHEL/owner before undertaking the geo-technical investigation work. However, the net safe bearing capacity (SBC) of shallow foundation to be adopted for the design of foundations during detailed engineering shall be limited to the values mentioned elsewhere in the specification and any value of net SBC higher than the one indicated shall not be accepted. However, bidder shall note that the net safe bearing capacity and foundation depth/ safe load carrying capacity of pile to be adopted for design during detailed engineering stage shall be got approved by BHEL/owner Foundation System General Requirements a. All equipments/structures shall be supported on suitable open foundation/pile foundation along with any special requirements/remedial measures/treatment called for subsoil/foundations as approved by BHEL/owner.

3 1x370MW CCPP,YELAHANKA SPECIFIC TECHNICAL REQUIREMENTS SPECIFICATION NO. VOLUME II B SECTION - C SUB-SECTION - REV.01 DATE SHEET 2 OF 4 b. All foundations shall be designed in accordance with the provisions of relevant part of the latest revision of Indian Standards. c. No foundation shall rest on filled up soil./loose soil d. No foundation shall rest on expansive soil. e. A combination of open and pile foundations shall not be permitted under the same structure. f. Foundations shall be designed to resist loading derived from environmental loads including loads due to wave, current, wind or seismic, gravity loads, construction loads, static and moving loads and any other loads as applicable and as specified elsewhere in the specification. g. Foundation shall be designed for worst combination of loads as described elsewhere in the specification Open foundations In case shallow/open foundations are adopted then the following shall be strictly adhered to. i. Minimum width of foundation shall be 1m. ii. iii. Minimum founding level shall be as mentioned in Table-1. The net safe bearing capacity (SBC) of shallow/open foundations at different founding level shall be limited to the values as mentioned in the following Table-1 and any value of net SBC higher than the one indicated shall not be accepted. However, bidder shall note that the net safe bearing capacity and depth of foundation to be adopted for design during detailed engineering stage shall be got approved by BHEL/owner.

4 1x370MW CCPP,YELAHANKA SPECIFIC TECHNICAL REQUIREMENTS SPECIFICATION NO. VOLUME II B SECTION - C SUB-SECTION - REV.01 DATE SHEET 3 OF 4 Table-1 Net Safe Bearing Capacity Type of Founding Allowable Finished Remarks Foundation Level (m) Bearing Ground Pressure* Level (t/sqm) (FGL) in m Spread Footing/ Raft Foundation (+) (+) (+) (+) Minimum founding level shall be RL(+)900.00M (+) (+) iv. It shall be ensured that all foundations of a particular structure/building/equipment shall rest on one bearing stratum. v. The permissible settlement as mentioned under para permissible settlement of foundations or permissible settlement from functional requirement which ever more stringent shall be adopted for the design. vi. vii. The permissible total settlement of cooling tower foundation resting on soil shall be restricted to 25mm in case of spread footing and 40mm in case of raft foundation. However, the permissible differential settlement of foundation resting on soil mass shall be governed by IS: 1904 and from functional requirements whichever is more stringent. Analysis and proportioning of footings to minimize differential settlements shall be carried out for all major foundations and the same shall be submitted for BHEL/owner s approval.

5 1x370MW CCPP,YELAHANKA SPECIFIC TECHNICAL REQUIREMENTS SPECIFICATION NO. VOLUME II B SECTION - C SUB-SECTION - REV.01 DATE SHEET 4 OF 4 viii. ix. In case any soft soil/loose stratum is met with at the founding level or below during execution, the same shall be completely removed and filled back with PCC 1(cement):3(sand):6(stone aggregates) up to desired foundation level. Expansive soil shall not be used for filling/back filling around foundation x. No foundation shall be resting on expansive soil.

6 Field Borelog Project: 1 x 370 MW Combined Cycle Power Plant at Yelakanka, Karnataka B.H.No.: 22 Location : Cooling Tower Red. Lev. (m) : Term. Depth (m): 20 B.H. Coord. : X = , Y = Water Table (m): 12.6 Existing ground level Soil Description Depth 0.0 / N Value Remarks Reddish pink with yellow clayey sandy silt with traces of Reddish pink with yellow clayey sandy silt with traces of Pink with yellow clayey sandy sit (9, 12, 21) 33 (25,22, 16) 38 (10,13, 16) 32 (10,13, 18) 31 Pink with yellow clayey sandy sit Pink with yellow clayey sandy sit (11, 15, 20) 35 Pink with yellow clayey sandy sit Reddish pink with yellow clayey sandy silt (11, 14, 20) 34 Reddish pink with yellow clayey sandy silt Reddish pink with yellow sandy clayey silt (12, 16, 21) 37 Reddish pink with yellow sandy clayey silt 20.0 (16, 20, 26) 46 G(B) Page 45 of 351

7 Field Borelog Existing ground level Project: 1 x 370 MW Combined Cycle Power Plant at Yelakanka, B.H.No.: 31 Karnataka Location: Switch Yard Red. Lev. (m) : Term. Depth (m): 20 B.H. Coord. : X = , Y = Water Table (m): 9.8 Soil Description Depth 0.0 / N Value Remarks Reddish brown clayey silty sand with Reddish brown clayey silty sand with (8, 11, 13) 24 Reddish brown clayey silty sand with 3.0 (12, 16, 18) 34 Dark red with yellow ly clayey silty sand 4.0 Dark red with yellow ly clayey silty sand 5.0 (12, 15, 20) 35 Dark red with yellow ly clayey silty sand Reddish pink with yellow clayey sandy silt with Pinkish red with yellow clayey sandy silt with traces of (12, 15, 17) 32 Pinkish red with yellow clayey sandy silt with traces of 11.0 (13, 18, 21) 39 Dark pinkish red with yellow sandy clayey silt with traces of Dark pinkish red with yellow sandy clayey silt with traces of (17, 19, 25) 44 Pinkish yellow sandy clayey silt with traces of Pinkish yellow sandy clayey silt with traces of (18, 22, 26) 48 Pinkish yellow sandy clayey silt with traces of 18.5 Pinkish yellow sandy clayey silt with traces of 20.0 (18, 24, 30) 54 G(B) Page 54 of 351

8 M/s Deccaan Engineers (India) Geo-Technical Investigation Report BHARAT HEAVY ELECTRICALS LIMITED POWER SECTOR SOUTHERN REGION, 690, ANNA SALAI, NANDANAM, CHENNAI REPORT NO GT IS:1892 SUBSURFACE INVESTIGATION FOR FOUNDATIONS 5 SCPT, 4 PLT, 5 BORE HOLE 1X 370 MW KPCL YELAHANKA CCPP Table-A Field Bore Log BORE HOLE BH-5 Water table Below EGL:- NILL Bore Completed Date : LOCATION CT C0-ORDINATE (W), (N) RL THICKNESS -M SYMBOL SOIL DESCRIPTION DEPTH M N N SAMPLE Rock, DS Core details CR RQD GRAVEL CLAY SILT SOIL 1.0 Ø Ø Ø SILTY CLAY SOIL Ø SILTY CLAY SOIL Ø > SILTY WITH SANDY Ø >100 Page 32 of 82 Page 306 of 351

9 M/s Deccaan Engineers (India) Geo-Technical Investigation Report BHARAT HEAVY ELECTRICALS LIMITED POWER SECTOR SOUTHERN REGION, 690, ANNA SALAI, NANDANAM, CHENNAI REPORT NO GT IS:1892 SUBSURFACE INVESTIGATION FOR FOUNDATIONS 5 SCPT, 4 PLT, 5 BORE HOLE 1X 370 MW KPCL YELAHANKA CCPP Table-A Field Bore Log BORE HOLE BH-5 Water table Below EGL:- NILL Bore Completed Date : LOCATION CT C0-ORDINATE (W), (N) RL THICKNESS -M SYMBOL SOIL DESCRIPTION DEPTH M N N SAMPLE Rock, DS Core details CR RQD Ø > SILTY WITH SANDY Ø >100 Page 33 of 82 Page 307 of 351