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CONSTRUCTION OF NAIROBI RING SUBSTATIONS – LOT A AND LOT B CONTRACT KETRACO/PT/018/2011

No. Clarification/Query Response

105 According to General Specification, the maximum Conductor temperature specified as 80ºC. Whereas Guarantee Technical Particulars indicates the permissible core temperature as 90 ºC for continuous operation. Hence please clarify the required temperature.

The specification is correct in that there are two different temperature requirements for the two different conducting media. The transmission line conductor maximum temperature is 80degC and the HV cable conductor maximum temperature is 90degC.

106 Volume-1, technical specification 220kV circuit breaker failure protection calls for “mid diameter circuit breakers, separate breaker fail protection”. Whereas volume-2, price schedule does not indicate circuit breaker fail protection panel. Hence please clarify the requirement of separate CB fail protection panel. If the panel is required please include the same in price schedule.

You are required to make proposals in your bid for the location of the mid-diameter CBF to suit your protection scheme design. Make reference to any additional panels within your proposal methodology.

107 Lot – A, Volume -1 page -260 of 325,Clause 18.3.3.2, Technical Specification indicates maximum thermal resistivity of ground is 2.0km/W. Whereas in Volume -2, page 23 of 150, Guaranteed technical particulars for 66kV cable, clause 4.10, specify the maximum thermal resistivity as 6km/W. Hence please clarify the maximum thermal resistivity.

The two thermal resistivity figures specified are correct as they apply to two different technical requirements.

108 Lot-A, Drawing No: 64161A/PBP/D/0052, Athi River 220/66kV Substation Single Line Diagram indicates the Neutral Earthing Resistor at 11kV Earthing Transformer. Whereas price schedule does not include this Neutral Earthing Resistor.

The contractor shall be responsible for the design. The bidder is to indicate what the prices are based on.

109 Lot – A, Athi River substation Price Schedule does not indicate the requirement of protection & Control panel for 66kV Bus coupler(2 No’s) and 66kV Bus section(1No ). Hence please include the same in price schedule.

Incorporate the bus-couplers and bus-section prices into the feeder circuit prices. Clarify these additions within your proposal methodology.

110 Lot – B, Volume-1, page 23 of 333, Clause 14.3.2.1, Ground Thermal resistivity indicates not greater than 2.7km/W. Whereas in Volume-2, Page 92 of 126, Clause 4.10 specify the maximum thermal resistivity as 6Km/W. Hence please clarify the maximum thermal resistivity.

The two thermal resistivity figures specified are correct as they apply to two different technical requirements.

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111 Lot- B, Drawing No: 64161A/PBP/D/0115, Koma Rock substation and 64161A/PBP/D/0110 Ngong Substation Single line Diagram Indicates neutral earthing resistor at 11kV side for Earthing Transformer. Whereas price schedule is does not introduce the above item. Hence please clarify.


112 Lot – B, Koma Rock Substation & Ngong substation Price Schedule does not indicate the requirement of protection & Control panel for 66kV Bus coupler(2 No’s) and 66kV Bus section(1No.) Hence please include the same in price schedule.

Incorporate the bus-couplers and bus-section prices into the feeder circuit prices. Clarify these additions within your proposal methodology.

113 Lot B, Koma Rock substation, 220kV cable: price schedule calls for three phase disconnecting link box at terminal locations. Please indicate the type of bonding system, whether solid bonding or single bonding is required at the terminal end.

It is the bidder's responsibility to provide a design that meets the requirements of the technical specification

114 Lot B, Koma Rock substation, 220kV cable: Price schedule calls for three phase link box for cross bonding and the mentioned quantity is zero. However we presume that the cable joints shall be carried out by cross bonding system. Hence please clarify the requirement of bonding system. If required please include in the price schedule.

It is the bidder's responsibility to provide a design that meets the requirements of the technical specification

115 Lot-B, Drawing no. E50105-A1330-A002-0, 220/132kV Dadora substation, 220kV Diameter 2 protection & metering, Single Line Diagram, calls for two relays for breaker fail protection. Whereas drawing no. 64161A/PBP/D/0101, Dandora 220/132kV substation, single line diagram specify single relay for Circuit breaker fail protection. Hence please clarify the requirement of relays. We also request you to clarify the mid diameter, number of Circuit breaker fail relay for other substations (viz Koma rock & Ngong substations)

The single line diagram indicates typical protection functions and the relay locations and is a combination of original and proposed schemes. Within your proposal you are required to determine the appropriate number of relays in order to achieve the specified CBF scheme requirements.

116 Lot-B, Volume-2, Page no. 60 of 75, Dandora substation price schedule, item no. 2.2, calls for 220kV busbar protection modification. Please advise the type of existing busbar protection, whether high impedance or low impedance. Also indicate the make of busbar protection relay.

Since Dandora substation is connected in a ring bus format, there is no existing busbar protection. The scope of this contract includes the provision of busbar protection.

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117 We kindly request you to agree the extension of closing date for one month more (until 23 May 2012).

Request rejected

118 We request you to kindly examine the possibility of extending the bidding period for one month.

Request rejected

119 Lot-A Clause No: 13Earthing/Auxiliary Transformer - Earth Fault current required is 750Amps for 30 SecAs per drawings no:6416A/PBP/D/0031 Rev-P1 Dated 01.06..2011, the Earthing/Auxiliary transformer earth fault current as 500A for 10 Sec, Please clarify.

The bidders shall price for the provision of 750 A / 30 sec . rated equipment.

120 Lot-A Clause No: 19.17.2.1As per Specification, HVAC, Fire detection , suppression for control building to be included in scope. As per price schedule the quantity for mechanical building services is not included. Please clarify the same and provide the revised schedule indicating mechanical building services.

Include these items within the price for the control building.

121 EarthingEarthing as per IEEE80Earthing for the substation will be provided as per IEEE80. We propose Mild Steel rod as main earth mat conductor(buried in ground at 600mm depth) and galvansied steel flat of required size for equipment connection. Please confirm.

The design of the substation is the responsibility of the bidder.

122 Lot-A Clause No: 19.17.1.2Lux Level for outdoor area 1) Machinery area -200 Lux2) Platforms/ladders (Active)- 50 LuxWe presume that the switchyard area lux level will be 50 lux. Please clarify the machinery area requirement in switchyard


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123 Lot-A Clause No: 14.6DG switchgear RoomAs per substation layout separate building for Diesel Generator is not indicated. We presume the DG switchgear room shall be a part of Control room. Separate building for DG is not envisaged. Please confirm.


124 ACSR ConductorACSR conductor details for 220kV and 66kV substationKindly provide the type of ACSR conductor for 220kV and 66kV substation.


125 Addendem-2, Clause: 8.2.1.6As per this clause bus bar protection for two future spare diameters to be provided in new substation.Please clarify the scope of Bus bar protection for 220/132kV Dandora substation. We presume the main unit and bay unit for substation extension bay is already available in this substation. Please clarify.

See Item 116

126 Altitude derating factorAs per specification the altitude for substation is above 1000mClearance to be derated for altitude factor. We presume that the bay width and clearance to be modified. Kindly specify the clearance for higher altitude. Please specify the IEC standard to be followed for the clearance.

The design of the substation is the responsibility of the bidder. The specification states all relevant IECs.

127 LT Power CableAluminium cableWe propose aluminium cable with PVC insulation for substation. Please confirm.

The design is the responsibility of the bidder. The design shall not deviate from the technical specification.

128 Bus HeightDANDORA 220/132kVPlease specify the height of the existing substation main bus, equipment bus and Strung bus.

It is the bidders responsibility to establish the existing design available during the pre-bid site visits.

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129 ACSR ConductorDANDORA 220/132kVPlease specify the conductor details of the existing substation

It is the bidders responsibility to establish the existing design available during the pre-bid site visits.

130 LVAC systemDANDORA 220/132kVWe presume that the existing arrangement of AC & DC auxiliary system will cater to supply for the additional new bay requirement. Please confirm.

It is the bidders responsibility to establish during the pre-bid site visits.

131 LVAC systemDANDORA 220/132kVWe presume that the existing control room will have space provision to place the additional panel for the present scope. Please confirm and provide the the existing control building details.

It is the bidders responsibility to establish during the pre-bid site visits.

132 Location of the metering panelMetering panel locationWe presume that the metering panel will be located in control room building. Separate room/building for metering is not envisaged. Please confirm.


133 During checking the drawing of ATHI RIVER SUBSTATION, we find that the drawing 64161A/PBP/D/0027 is repeat two times, and the drawing 64161A/PBP/D/0028 is missing between 0027 and 0029. Please to provide the drawing 0028.

Attached.

134 Under the clause 21.2 of ITB, the original and all copies of bid shall be signed by a person duly authorized to sign on behalf of the Bidder. Please clarify if it is necessary to seal/stamp on each page of the original and all copies of bid? If necessary, please inform in case of consortium, only seal/stamp by leader of consortium is acceptable?

See 'All pages of the bid where entries or amendments have been made shall be signed or initialled by the person signing the bid.'For JVA refer to 21.3.

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135 In the Addendum 1, you changed the terms of payment to be on CIP basis.Please confirm can we change the CIF in the Price Schedules to CIP? If it is confirmed, can we delete the column of "Dock Dues and Inland Transport to Site" in the Price Schedules and quote CIP price only in Euro to you?

Payment terms are CIP as stated in the BDS and Addendum 1. The column should not be deleted but CIP shall replace CIF in the price schedules.

136 As mentioned in “3.Bidders qualification criteria”, the audited balance sheets for the last five years should be submitted. But in our country (China), the audited balance sheets for year 2011 will be issued by end-April, 2012 at the earliest, which is a little later than bid opening date (April 18th, 2012). So can we submit the audited balance sheets of year 2006-2010 instead?

Yes

137 In the tender SECTION VII FORMS AND PROCEDURES 1.1 Bid Form: Please inform us the Loan/Credit No, we can’t find it in the bidding documents.Please inform us the name of the adjudicator, we didn't find it in the BDS, and also inform us his duties/works scopes.“We agree to abide by this bid, which consists of this letter and Attachments 1 through number Here to….” We don’t understand what the number indicates, please clarify.

This shall be provided prior to contract award.

138 In the tender” SECTION VII FORMS AND PROCEDURES FORM 3a-contracs of similar value, nature and complexity_item11” Please fill in also forms 3b to 3h”.There is no forms 3c to 3h in your tender documentation, please provide form from 3c to 3h to us.

Forms 3c to 3h are not provided. Complete 3a & 3b.

139 Under the clause PC23.2 of volume II -Section V -Particular Conditions, The Contractor shall include for two Employer representatives and one Engineer representative attending 6 FATs. (in LOT-B, 7 FATs). Please inform how many days or weeks one FAT will take?

This is to be determined by the bidder.

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140 In BDS” In general, for items of supply, the vendors must have successfully manufactured and supplied in any one year during the last five years, the quantity being proposed for subcontracting, which are in satisfactory operation/use for the past two years as on the date of bid opening”. We don’t understand what the quantity indicates, please clarify.What dose “any one year” indicates, only one year or every year of five years?What documents are needed to support the above mentioned history?“For items of supply”, whether this requirement is only applicable to major items?

The 'quantity' is the number of units intended to be supplied by a subcontractor for this contract. The evidence required is for the same quantity to have been supplied on other contracts within at least one year out of the last five years. This evidence shall be provided as supplementary information to the Manufacturer's Authorisation.

141 Clause “PC 46 Disputes and arbitration” in the particular conditions,What is the word “DB” means?

This is stated within the General Conditions of Contract.

142 In the Lot-B 17.4.2 cable laying condition. The bidder documentation mentioned that trench details are provided in drawings given in Section VI, Appendix A. There is no cable installation trench section drawing in the tender documentation. Kindly be provided the relevant drawing.

See Addendum 3

143 Dandora Substation Extension of the Control System is not specified method in tender.Please clarify the BCU control model for extension bays whether is acceptable.

See Addendum 2.

144 Inside the Tender documentation details regarding the line traps are missing.Please provide us with more information regarding line traps (inductance etc.) and also provide us with relevant technical schedules regarding the line traps.


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145 Inside the Tender documentation details regarding the post insulators are missing.Please provide us with more information regarding the post insulators (type, voltage level, mechanical strength etc.) and also provide us with relevant technical schedules regarding the same post insulators.


146 Inside the Tender documentation details regarding the surge arresters are missing.Please provide us with more information regarding the surge arresters (discharge current, rated voltage etc.) and also provide us with relevant technical schedules regarding the same surge arresters.

See Addendum 3.

147 Concerning the 66 kV XLPE cable inside the Athi River Substation, please provide us with an information regarding which metallic bonding screen method must be applied (both-end bonding, single-point bonding or cross-bonding) ?


148 Ngong & Koma Rock layouts show reserved space (in length 32m) inside the 220 kV zone which can be interpreted as a space for future extension by means of adding the 3rd diameter.Please, verify if the same space is essential for future extension and therefore is absolutely needed or verify that the same space can be subtracted from the layouts given inside the Tender.

The design of the substation is the responsibility of the bidder. Future extension shall not be inhibited by the design for this phase of the works.

149 According to substation layouts given inside the Tender, thirteen 66 kV bays are planned per substation which holds 66 kV voltage level.Should the additional space be provided for future 66 kV bays or space for thirteen 66 kV bays (according to layouts) is enough ?If future 66 kV bays are to be added, please advise us concerning additional space.

The design of the substation is the responsibility of the bidder. Future extension shall not be inhibited by the design for this phase of the works.

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150 Substation layouts and elevations hold the system parameters table. Current rating is defined to be 2000A (for both 220 & 66 kV switchgear). It is unclear should the current rating of 2000A be applied on only the busbars or only on the switching equipment or it should be applied on both.Please, advise us regarding this matter.

The current rating for the substations is 2000A.

151 According to Schedules of Technical Information for 220 & 66 kV open terminal switchgear 1.2, 1.5, 1.6 and according to Technical drawings given inside the Tender, planned substations are indeed for system voltages 220 & 66 kV.However, due to the altitudes that are exceeding 1000m correction factors must be taken into account. This leads us to a conclusion that equipment rated voltages are to be 420 & 123 kV and that adequate voltage clearances (according to IEC) are to be respected.Please, confirm that 420 & 123 kV equipment is indeed necessary or confirm that equipment specified inside the Schedules of Technical Information already takes into account standard correction factors due to altitudes higher than 1000m.Also, if 420 & 123 kV equipment is necessary please provide us with the corrected Schedules of Technical Information.

The bidders shall ascertain the correct values for the equipment being offered.

152 Transmission line tower foundation detailed designsSection VI – Part B – Paragraph 5 (Steel tower design)ANDSection VI – Part B – Paragraph 6 (Foundation design)“Successful bidder will obtain the tower detail design from KETRACO. Workshop detailing remains the responsibility of the Contractor.”We understand that the successful bidder will also obtain the tower foundation detailed designs from KETRACO.Please confirm.

Confirmed

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153 Transmission line tower foundation detailed designsSection VI – Part B – Appendix B (Bid Drawings)Towers and foundation drawings are included in the tender documents of Lot A but not in the tender documents of Lot B.Please clarify whether these drawings are applicable to Lot B or not.

Lot B will be similar but not identical to Lot A. Full details of towers and foundations will be provided to the sucessful bidder.

154 Existing telecommunications and OPGW systemsSection VI – Part A – Appendix BAppendix B, received as part of Addendum No. 2, refers to a project called “Lot 3” and to works in substations Rabai and Embakasi.Is this applicable to the present tenders? Please clarify. Specifically:- For Paragraph “Introduction” (page 2): Please provide the updated status of KPLC’s SCADA/EMS project (progress of installation and commissioning and expected date of project completion)- For Paragraph “Lot 3 scope” (page 2): Is this paragraph applicable? Item 9.2.2.2. is mentioned here but it does not exist in the Technical Specifications for Substations of either Lots A or B.

The scope of this project includes integration into the existing telecommunication systems. The scope of work at Athi River and Isinya substations involves integration into the system being installed within the ongoing Lot 3 contract.

155 we kindly request you to study the possibility to extend the deadline at least for one month till 18 May

Request rejected

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156 According to China's banks relevant regulations, the bidder’s security must be issued by the original bidder specifying a specific expiry date. We must specify the specific expiry date on the bidder’s security (bank guarantee) under this restriction: Original textThis guarantee will expire: (a) if the Bidder is the successful bidder, upon our receipt of copies of the contract signed by the Bidder and the performance security issued to you upon the instruction of the Bidder; or (b) if the Bidder is not the successful bidder, upon the earlier of (i) our receipt of a copy of your notification to the Bidder of the name of the successful bidder; or (ii) twenty-eight days after the expiration of the Bidder’s Bid. Modified as:This guarantee shall take effect from the date of deadline of bid submission and shall remain valid for a period of two hundred and eight(208) calendar days thereafter or until the 12th of November, 2012, whichever occurs first, and during the period of any extension thereof that may be agreed upon between you and the Bidder with notice to us. If we are the successful bidder, we agree that our bid security will be extended and the expiry date thereof will be the date when we execute the Contract Form and furnish the performance security to you.we attach the two edition of modification with this email. We would like to know that does the Employer agree to this description?And which description is acceptable by the Employer. Please respond with the exact text.

The proposed Modified text is not acceptable. However, the Original text shall be modified as follows:

This guarantee will expire: (a) if the Bidder is the successful bidder, upon our receipt of copies of the contract signed by the Bidder and the performance security issued to you upon the instruction of the Bidder; or (b) if the Bidder is not the successful bidder, upon the earlier of (i) our receipt of a copy of your notification to the Bidder of the name of the successful bidder; or (ii) twenty-eight days after the expiration of the Bidder’s Bid. i.e. on or before (bidder to insert appropriate date as agreed with their bank ).

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157 NCC and RCC database modifications worksSection VI – Part A – Paragraph 9 (Substation Control System) – Sub-paragraph 9.2.1

It is likely that, for warranty purposes, the NCC and RCC database modification works which are required as part of the Scope of Works will have to be done by the NCC/RCC original equipment manufacturer (OEM). Therefore the Contractor will have no other option than to subcontract this task to the OEM.

Please confirm your acceptance.

It may be more economical for KETRACO to award this task directly to the OEM in a separate Contract. Therefore we would suggest removing this task from the Scope of Works of the Project.

This is not acceptable. The Scope of Works shall remain unaltered.

158 Floor area of control buildingsSection VII – Part 1.2 (Price Schedule) – Item 10.15 (Substation control / relay building) of Athi River Substation, Isinya Substation and Ngong Substation

The price schedule indicates “Substation control / relay building (Nominal floor area 600sq. m.)”

However we had understood form the pre-bid meeting and site visits that the control building design is the Contractor’s responsibility.

Please clarify “(Nominal floor area 600sq. m.)” in the price schedule item description.

Although the design is the responsibility of the bidder, the bidder shall price on the basis of the nominal floor area.

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159 Current ratings of conductors and tubes 220kVSection VI – Part A

What are the required nominal current ratings for the 220kV feeders (OHL outgoing feeders, underground cable outgoing feeders and transformer feeders)?

This is required for our design of switchyard conductor and tube sections.

The required ratings are stated within the technical specification and technical parameters.

160 220kV Cable route (Dandora – Koma Rock)Addendum No. 3 – Item 2 (HV Cable Route Length)

We noted that the required length of single core cable should be changed to 36,000m in the price schedule due to the increase of the route length from Dandora to Koma Rock to 6km.According to our observations at the site visit, the route length between Koma Rock and Dandora is between 3 and 4km.Please confirm whether the position of Koma Rock new substation likely to changeas this may change the conditions of access to the site.

Please confirm whether any other item of the price schedule for Dandora “HV Cable and Accessories 220kV direct buried” should also be amended.

The location of the purchased land area for Koma Rock substation will be provided following contract award. The bidders shall state on what basis their prices are based.

161 Training Cost for the EmployerIn section 1.32 Training, it is mentioned that trainings shall be provided to KETRACO personnel and should be included in the Contract Price. Kindly confirm if the accommodation costs and allowance as detailed in the Particular Conditions of the Contract for FAT should also be applicable for Training and such costs shall be borne by the Contractor.

Confirmed.

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162 Section V1 Part- A Technical specification Lot-A Clause No : 8.2.4The substation works contractor shall supply and install the optic fiber cable between the main OTB and the OTB located in the applicable protection panelWe assume only one FOTB ( Main) which will be located in telecom room . All Patch cards from the Main Relays will be connected to FOTB( Main) . There is no separate OTB panels in Control Room. Please Confirm.

This is detailed design and will be subject to the design review process following contract award.

163 Section V1 Part- A Technical specification Drg.No. 64161A/PBP/D/0052 , Rev-P1 Single line diagram indicates the tariff metering CT Class as 0.2As per 64161A/PBP/D/0030 , Rev-P1 , 66KV Protection circuit indicates the tariff metering CT Class as 0.2s . Please confirm.

All tariff metering CTs shall be Class 0.2s

164 Section V1 Part- A Technical specification Lot-A Clause No : 8.2.1.2For distance relays, where the length of the OHL permits, the main distance protection shall preferably be designed for direct interfacing to a pair of optical fibers for tele-protection communication. Should line length be a limiting factor then a digital tele-protection signalling unit orMultiplexer shall provide the necessary tele-protection communications between circuit-end relays.Please provide the Details of OHL length details and availability of OPGW to decide the requirement Mux for inter tripping. ( applicable for 220kV & 66kV system)

The provision of OTB’s shall be a feature of your design proposal.

165 Civil worksControl building layout plan & sectionPlease provide the layout plan & section

The design is the responsibility of the bidder.

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166 Civil worksSoil report Please provide the soil parameters in order to finalise the type of foundations.

Site surveys and soil investigations are the responsibility of the contractor. The bidder is to indicate what the prices are based on.

167 Civil worksCivil design compliance As per spec requirement all design shall be incompliance with BS standards – Please confirm.

The design is the responsibility of the bidder. The bidder shall not deviate from the requirements of the specification.

168 Civil worksCar parking Please clarifiy the whether the requiremnt of car parking is covered or uncovered car park.


169 DANDORA Substation Schedule No 7 and Single Line DiagramDiscrepancy is observed in the number of quantities as under:

Item As per Schedule#7 As per SLDCable sealing end 0 No. 12 Nos.Post Insulator - Upright 46 No. 52 Nos.

The single line diagrams are indicative. There are no post insulators shown on the SLD.Cable sealing end quantities for the cable feeders are provided within the Koma Rock Price Schedules.

170 DANDORA SubstationRequest you to furnish existing earth mat layout details as the same is required for foundation volumes.

This information can be obtained by the contractor following contract award.

171 DANDORA SubstationRequest you to give technical details of existing conductor and Aluminium Tube used for existing bays.

This information can be obtained by the contractor following contract award.

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172 DANDORA SubstationWe understand that new SAS is to be installed for the Dandora substation and also that we can connect the existing system in the substation to new SAS using existing interface i.e. RTU. So, the old system will be connected to new SAS instead of NCC and new gateways shall be provided for NCC . Please confirm.Please also confirm if new RTUs are required

See Addendum 2.

173 LOT A & LOT B - 66kV Line Trap RequirementRequest you to furnish Technical Specification & Technical Data Sheet of 66kV Line Trap.


174 Isniya New Substation, Schedule No.5, Item No.10.47Exact scope of civil works under the item is not quite clear. Kindly confirm the scope to be considered.

See Addendum 3 - Item 1

175 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings, - 19.6.1Site SurveyPlease furnish finished grade level for the proposed substations.


176 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings, - 19.6.1Site SurveyPlease furnish Contour map for the proposed substations.

Topographical information is to be obtained by the bidders using the location coordinates given in the Bid Document and in addenda.

177 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings, - Substation 19.16.9control/ relay building.Please clarify the type of building to be provided RCC or Steel


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178 Volume 2 of 2, Section-VII, Forms & Procedures, Schedule 1 10.15Substation control/ relay building.Please furnish the internal and external finishing schedules for the building.


179 Volume 2 of 2, Section-VII, Forms & Procedures, Schedule 1 9equipment support structures.Please furnish the type of equipment support structure to be provided ( lattice or Pipe).


180 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings, - 19.16.13.3Car ParkingPlease clarify whether car parking is covered or only paved type.


181 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings, - 19.16.13.3Car ParkingIf car parking is covered type, please clarify steel or RCC structure to be provided.


182 Rail cum road for transformer - Substation layout (220/66kV Athi river & 66kV Isinya)Please clarify whether rail track is to be provided from transformer to nearest access road.


183 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings, - 19.16.13.1Permanent access road.Please furnish the width of kerb stone to be provided.

The design is the responsibility of the bidder.This is detailed design and shall be subject to the design review process following contract award.

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184 Volume 1 of 2,Section-VI, Part-A, Technical Specifications and drawings, - 2.11Galvanised worksPlease furnish the thickness of galvanization to be provided.

The bidder shall not deviate from the specification.This is detailed design and shall be subject to the design review process following contract award.

185 Volume 2 of 2, Section-VII, Forms & Procedures, Schedule 1 10.43, 10.44TransformerWhether soak pit is required for transformer, please clarify.

Please refer to the appropriate IEC.

186 Volume 2 of 2, Section-VII, Forms & Procedures, Schedule 10.14Substation gatehousePlease clarify the type of gate house to be provided RCC or Steel.


187 Volume 2 of 2, Section-VII, Forms & Procedures, Schedule 1 10.4Land scapingPlease furnish the specification and extent of landscaping to be provided.

The design is the responsibility of the bidder. The bidder is to indicate what the prices are based on.

188 Volume 2 of 2, Section-VII, Forms & Procedures, Schedule 1 10.5Surface ChippingWe trust the scope of surface chipping means spreading of 150mm thick natural gravel or crushed stone, please confirm


189 Volume -1 of 2,Dandora 220/66kV layout -64161A/PBP/L/0100 & SLD -64161A/PBP/D/0100 Dandora LayoutAs per single line diagram equipments shown in red are to be supplied under present scope, where as in layout drawing equipments marked in red was mentioned as future scope, please clarify.

The equipment marked in red on the layout is within the scope of this project. The equipment marked in black is existing.

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190 Section V1 Part- A Vol 1 of 2, Clause No : 19.17.2.1Thermal insulationkindly provide the specification for thermal insulation (for ducts and chilled water pipes of both above ground and under ground)


191 Section V1 Part- A Vol 1 of 2, Clause No : 19.17.2.5Chiller systemKindly provide the type of chiller system ( reciprocating / scroll/ screw chiller) to be considered for air-conditioning


192 Section V1 Part- A Vol 1 of 2, Clause No : 19.17.2.5Room dimensionsKindly provide the dimensions of each rooms


193 Section V1 Part- A Vol 1 of 2, Clause No : 19.17.2.6Type of system for Battery roomBoth Air conditioning & ventilation system ( both working in same time) cannot be done for the battery room. Kindly confirm

The requirements for the battery room are stated clearly within the technical specification.

194 Section V1 Part- A Vol 1 of 2, Clause No : 19.17.2.1Chiller locationPlease confirm the location of the chiller


195 Section V1 Part- A Vol 1 of 3, Clause No : 19.17.2.1We have considered horizontal split casing pumps for condenser & chilled water pumps. Please confirm


196 Section V1 Part- A Vol 1 of 2, 12.5Transformer fire protectionWe have considered nitrogen fire protection for transformers. Please confirm


197 Section V1 Part- A Vol 1 of 3, 12.5Fire detection & Fire suppression systemUnder fire protection system fire detection, fire suppression system has not been given but under civil works (Vol 1 of 2, Sec-VI, Page 314 of 325,clause-19.17.2.1) the same has been given. Kindly provide the specification and the area for which the same has to be considered.

Fire protection systems for transformers and buildings shall not be confused.

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198 Section V1 Part- A Vol 1 of 4, 12.5Scope of hydrant systemSpecification does not calls for hydrant system, kindly confirm the scope of hydrant system for switchyard area and if is there kindly confirm the distance of the tapping point to be considered and the pressure available at that point.


199 Section V1 Part- A Vol 1 of 5, 12.5MVWS systemSpecification does not calls for MVWS system for cable cellar room. kindly confirm the same.

Section 12.5 refers to fire protection associated with transformers only.Medium velocity water spray systems are not a preferred solution.

200 Section V1 Part- A Vol 1 of 2, Clause No : 19.17.2.1Tapping pointkindly confirm the location of the tapping point to be considered and the pressure availability.


201 Lot AVII, 4, Schedule Nº3A. Item nº1.5 à Are the fittings for OPGW and ACS included in this item?

No. These are included in items 3.5 to 3.7.

202 Lot AVII, 4, Schedule Nº3A. Item nº3.2 à Are the Tension Sets in Substation Gantry and Tower AP5B (new)” included in this item? If they are included, the number of tension sets shall be 6(for Ap5B new)+12(for terminal tower) + 6(for Gantry) = 24 tension sets

Quantities are correct. 6 for AP5B(NEW) and 6 for the terminal tower.

203 Lot AVII, 4, Schedule Nº3A. . Item nº3.2 à Since there are three new towers, one “Earthing type” is missed.

There are only 2 new towers.

204 Lot AVII, 4, Schedule Nº3A. Item nº5 àTower “AP5B (new)” is missed in the schedule.

AP5B(NEW) will be an existing tower therefore is not in this scope.

205 Lot AVII, 4, OPGW and ACS fittings drawings are missed.

These will be provided to the sucessful bidder.

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206 Lot AVII, 4, Schedule Nº3B. Item nº1.1 à Single Canary has to be used for Athi River 220kV OHL. Why “Quad” is described in the item 1.1.?

Item 1.1 should read "six phases of single canary conductors".

207 Lot AVII, 4, Schedule Nº3B. Item nº3.2 à Are the Tension Sets in Substation Gantry included in this item? If they are included, the number of tension sets shall be 12(for terminal tower) + 6 (for Gantry) = 18 tension sets

Quantities are correct. 6 for AP5B(NEW) and 6 for the terminal tower.

208 Lot AVII, 4, Schedule Nº7. Item nº3.2 à Are the Tension Sets in Substation Gantry included in this item? If they are included, the number of tension sets shall be 12 (for both Gantries) + 12 (for Terminal Tower) = 24 tension sets

No, tension sets on gantries are low duty downlead sets.

209 Lot AVI, 4.2.3.1, Regarding Circuit Breaker Operating Mechanisms, we can read that the circuit breaker shall be suitable for single phase autoreclose and in the Price Schedule (7-1-2-2) we can see in the description the following text “Circuit breaker (3-phase)”, so please, could you clarify if the priority is the 3ph Circuit breaker o single phase autoreclose?

The 3-phase circuit breaker shall be suitable for single phase autoreclose.

210 Lot AIV, 24, Are Precommisioning activities included within the Time of Completion (18 months) ? Could you please send a list of activities (functional test) to be performed during Precommisioning?

Precommisioning activities are included within the Time of Completion (18 months). These are to be as per IEC standards and the technical specification.

211 Lot AWill the ad-hoc financing provided by EIB and AFD cover 100% of the project cost? If not, which percent?

See the Invitation for Bids for details.

212 Lot AThe funds provided by the above mentioned banks, will be locked into a project account and therefore funds will only be disbursed by the banks to pay pre-approved invoices to the contractor

Payment terms are within GCC 12

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213 Lot ADoes the Government of Kenya explicitly guarantee Ketraco´s bank debt and payments to suppliers?

Bidders do not require this information

214 Lot BVII, 7-1-2-2, The item 1.7 of Ngong Subestation (Post Insulator) appears with a quantity of 33. Regarding plans and sections we only appreciate 21 post insulators.¿It’s possible that crosses between different height lines had been considered as insulators in price list? ¿What is the actual quantity?

The drawings are indicative only. For evaluation purposes quantities are to be as per the price schedules.

215 Lot BVII, 4, Schedule Nº3. Item nº1.5 à Are the fittings for OPGW and ACS included in this item?

Fittings are included elsewhere. See clarification no. 201.

216 Lot BVII, 4, Schedule Nº3. Item nº3.1 The number of single suspension sets shall be 12 (6 per tower)

Quantities are correct. Please note schedule 3A and 3B.

217 Lot BVII, 4, Schedule Nº3. Item nº3.3 The number of earth conductor ACS suspension sets shall be 2 (one at each tower).

See Item 216

218 Lot BVII, 4, Schedule Nº3. Item nº3.5 The number of earth conductor ACS tension sets shall be 10 (2 per angle and terminal towers plus gantry)

Quantities are correct.

219 Lot BVII, 4, OPGW and ACS fittings drawings are missed.

Will be provided to the sucessful bidder.

220 Lot BVI, 4.2.3.1, Regarding Circuit Breaker Operating Mechanisms, we can read that the circuit breaker shall be suitable for single phase autoreclose and in the Price Schedule (7-1-2-2) we can see in the description the following text “Circuit breaker (3-phase)”, so please, could you clarify if the priority is the 3ph Circuit breaker o single phase autoreclose?

See Item 209

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221 There is a statement in 1.1 Bid Form "We accept the appointment of [name proposed in Bid Data Sheet] as the Adjudicator. However, after we searched the BDS and even the whole bidding document, we failed to find out the Adjudicator you proposed. Is that you didn't propose any Adjudicator or there is some missed information?

This information shall be provided prior to contract award.

222 On the top right corner of 1.1 Bid Form, there is a "Loan/Credit No.", which we don't know what it refers to and what information to fill in. Could you please explain it for us?

Please use: CKE/1068.

223 220kV CableThe Length of 220kV XLPE cable is 18,000m in the price schedule but do not have any information about cable route. So, We presume this length form Koma rock S/S to Dandora S/S long enough to connect.

See Addendum 3, Item 2. 36000m of single core cable is required.

224 220kV CableIn this spec. LotB 17.2, cable routes are generally as shown on the map included in the tender drawings, but we can not find any cable route drawing. Please send the cable route drawing on the map.

Route is to be confirmed prior to contract award.

225 220kV CableConnection work scope: Please confime whether Connection work between Koma rack S/S and Danora S/S is in scope or out of scope.

In scope. See Technical Specification Section 1.2 - "The substation works are to include the associated diversion of one of the Suswa to Isinya 220kV double circuit feeders into the new Ngong substation and the 220kV cable interconnection between Dandora and Koma Rock."

226 66kV SA The quantity of Surge Arrester in the price schedule (36) and single line diagram (30) do not accord.Please confirm the quantity of 66kV SA at NGONG S/S and KOMA ROCK S/S.

The single line diagram is indicative. Use the quantity in the price schedule

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227 Dandara S/SThe lack of specifiaction about CB, DS rated current, we assume that CB, DS's rated current is same to other substation like 2000A. Please confirm above the rated current.

Confirmed. Price on this basis

228 Tower(Lot1 & Lot2)Please kindly confirm whether the quantity of each item is accurate especially regarding the quantity of tower on both lot1 and lot2. cause the quantities of insulator set are 60 set, but it is not according to the quantity of tower.

Please bid on quantities provided.

229 Substation control system at DandoraAddendum 2 - Revised Protection and SCS System Sections – Paragraph 9 (Substation Control System) – Su-b-Paragraph 9.1Quote This section details the supply (hardware and software) erection, testing and commissioning of the systems for control and monitoring of each of the new Transmission Substations 220/66kV and interfaces to existing substation control systems (SCS).UnquoteIt is not clear to us what the Scope of Works includes regarding substation control system at Dandora existing substation.An existing conventional mimic control panel exists at Dandora. Does the Scope of Works include the extension of this mimic control panel to cater for the new diameter?Does the Scope of Works at Dandora include the supply of a new control system compliant with IEC 61850?Please clarify.

The bidders have the option of pricing for extension to the existing control panels or providing new control panels. The bidders shall state the basis of their pricing.

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230 Covenant of IntegritySection VII – Part 3b – 4th paragraphQuote In the event that we are awarded the Contract, we grant the Project Owner, BNP Paribas and auditors appointed by either of them, as well as any authority having competence under European Union law, the right of inspection of our records.UnquoteWe understand that the mention “BNP Paribas” is not relevant and should be removed.Please clarify.

Confirmed.

231 Project completion timeSection VII - Part 6 - Appendix 4 (Time Schedule)QuoteThe said Schedule shall be such that the whole of the Works are completed in twelve months from the commencement date of the ContractUnquoteWe understand that “twelve months” should be replaced by “eighteen months” i.e. the project completion time.Please confirm.

See Item 61.

232 We kindly would like to ask for an extension of 4 weeks, with a new submission deadline of May 16, 2012

Request rejected

233 Regarding the VAT: Exemption to be promoted by Ketraco, does it apply only to import materials, goods and services or to the entire bid supplies (both local and foreign)?

See Item 9

234 Import duties / import declaration: which taxes are included in the exemption? See Item 9

235 Is there a procedure by bidders to apply for these exemptions? See Item 9236 Does the Kenyan law establish the need of having a permanent site/branch during

the performance of the contract?It is the bidders reponsibility to establish the laws of Kenya.

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237 Qualification Requirements. If bidding both lots A & B , Must we have a minimum average turnover, in substation works, of USD 50 million per year in the last 5 years (which would mean at least USD 250 million in last 5 years in total) or do you mean we must have at least one contract of this magnitude (50million) within the last 5 years?

On average, USD 50 million per year for each of the last 5 years ie USD 250 million.

238 Could you please provide a more detailed technical specification for current and voltage transformers as well as a more complete data sheet in order to be more accurate in our supply?

All relevant information is within the bid documents.

239 As required, We must submit a minimum expected organization project chart. We understand that as this stage of the project (bid submission) we only have to give the names of project manager, site manager and deputy site manager. Please confirm.

It is the bidders responsibility to submit the documents that are relevant for detailed evaluation of their offer.

240 Subcontracting is limited to 30%. Does it mean 30% per subcontractor or the sum of all subcontractors?

30% in total.

241 We haven’t found the location coordinates of the substations in the bidding documents. Could you please provide it?

This information is on the drawings provided.

242 Revising the information we haven’t found any restrictions regarding eligible country / origin for proposed suppliers. Please confirm. Is there any approved vendor list for the main equipment of this contract?

No

243 Please provide us the terms of payment for civil works The terms of payment within Addendum 1 shall be complied to.

244 Please confirm if we have to submit control building layouts at this stage of the project (bid submission)

It is the bidders responsibility to submit the documents that are relevant for detailed evaluation of their offer.

245 In drawing 64161A/PBP/D/0034 we see two (2) 11kV/0,433kV auxiliary transformers, please confirm if we have to supply only one (1) 33kV/0,433kV auxiliary transformer instead as per addendum 3. And 500kVA power as well?

See Addendum 3 Item 1

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246 Documents Comprising the bid. As indicated in ITB11 we must submit on paper: bid form, Price Schedules and Attachments 1 to 7. In point 11.4 we must submit on CD: Price Schedules in Excel format and Technical Information in Word, what do you mean by technical information in word? A bid form?

As a minimum, the Section VII Part 4 Technical Schedules.

247 Could you please provide us the price schedules in excel format? Refer to Item 1248 Please confirm that the contract price shall be a firm lump sum Confirmed249 Section II Instructions to bidders. The contract, is it 100% financed by AFD and EIB See the Invitation for Bids for details.

250 Does the Government of Kenya explicitly guarantee Ketraco´s bank debt and payments to suppliers?”

Bidders do not require this information

251 Except as otherwise specifically provided in the Contract, the Contractor shall bear and pay all taxes, duties, levies and charges assessed on the Contractor, its Subcontractors or their employees by all municipal, state or national government authorities in connection with the Facilities in and outside of the country where the Site is located. Could you please clarify what are the taxes, duties, levies and charges assessed on the Contractor?

It is the bidders responsibility to establish the requirements of the Kenya Revenue Authority.

252 Does the contractor have to get the insurance from the Kenyan insurances company or the contractor is allowed to purchase insurance in other counties, the Chinese insurance company for example.

The contractor shall not deviate from the requirements of Section VII, Part 6 Appendix 3. The identity of the insurers and the form of the policies shall be subject to the approval of the Employer.

253 Does the Employer have any demand/ restriction on the grade/level/qualification for the insurance company?

The contractor shall not deviate from the requirements of Section VII, Part 6 Appendix 3. The identity of the insurers and the form of the policies shall be subject to the approval of the Employer.

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254 Does the Owner agree that: When damage/accident caused by the owner or the contractor happened,The insurance franchise which is not covered in the insurance according to the insurance terms, then the part (owner or Contractor) that made this damage/accident should be responsible for the cost of the franchise?

No

255 The Second issue is about the Defects Liability Period: Reference from Section IV General Condition 27.8Does the Owner agree to define/set up the longest limitation for the Defects Liability Period? And how long the period will be?

No. The GCC remain as they are written. Any request to change the contract conditions shall result in the bid being disqualified.

256 There is limited power and water facilities at the Athi River and Isinya sites. Will the contractor have to source water and prime power at both sites at their costs or will Ketraco provide the utilities at a cost.

No facilities shall be provided by the Employer.

257 Has Ketraco performed any resistivity tests on the sites if so could you share the results


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258 According to China's banks relevant regulations, the bidder’s security must be issued by the original bidder specifying a specific expiry date. So we must specify the specific expiry date on the bidder’s security (bank guarantee) under this restriction:

Original textThis guarantee will expire: (a) if the Bidder is the successful bidder, upon our receipt of copies of the contract signed by the Bidder and the performance security issued to you upon the instruction of the Bidder; or (b) if the Bidder is not the successful bidder, upon the earlier of (i) our receipt of a copy of your notification to the Bidder of the name of the successful bidder; or (ii) twenty-eight days after the expiration of the Bidder’s Bid.

Modified as:This guarantee will expire: (a) if the Bidder is the successful bidder, upon our receipt of copies of the contract signed by the Bidder and the performance security issued to you upon the instruction of the Bidder; or (b) if the Bidder is not the successful bidder, upon the earlier of (i) our receipt of a copy of your notification to the Bidder of the name of the successful bidder; or (ii) twenty-eight days after the expiration of the Bidder’s Bid, which will expire on the date of 12th,Novmber,2011.

See item 156

259 The two sites have significant level differences. Is it Ketracos preference that we archive the lower level hence cut into the soil or would the preference be for achieving the higher level so back filling.


260 Reference is made to the letter of bid where the bidder shall indicate the name of the Adjudicator which is not mentionned in the Bid Data Sheet => Could you please give us the name of the Adjudicator for LOT A and LOT B ?

This shall be provided prior to contract award.

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261 Reference is made to the letter of bid where the bidder shall indicate the loan/credit n° which is not mentionned in the Bid Data Sheet => Could you please give us the Credit n° for LOT A and LOT B ?

See Item 222.

262 With Reference to Volume 2, Section VII, Form and procedures 3b, Covenant of Integrity => Could you please clarify who would be the "Project Owner" of Ketraco Contract Ketraco/PT/018/2011 LOT A and LOT B ?

KETRACO

263 Reference is made to the Technical specification of Protection relays (Fault recording).For LOT A in chapter 8.2.1.2 §k (Fault recording), it is mentionned that a "separate fault recorder should be provided"For LOT B in chapter 8.2.1.2 §k (Fault recording), it is mentionned that the "fault recording should be integral to the numerical protection"=> In order to ensure a common maintenance oriented technical characteristics, could you please clarify which design should be used for the fault recording : separated or integrated in relays ?

As per Addendum 2, separate fault recorders shall be supplied. In additional, the protection relays shall have integral fault recorders.

264 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings19.6.1, Site SurveyPlease furnish high flood level for the proposed substations.


265 Volume 1 of 2, Section-VI, Part-A, Technical Specifications and drawings19.6.1, Site SurveyPlease clarify whether high flood level is to be considered while fixing the finished grade level for the substations.


266 ConductorPlease inform the conductor used in the existing Dandora Substation

See item 129

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267 Substation Design and Layout

In view of the previous responses to clarifications, we understand that the drawings provided in the tender are indicative and used as reference only. The Bidder is responsible in proposing its design that shall conform to the tender specifications and IEC standards. Please confirm if our understanding is correct.

Your understanding is correct.

268 Please confirm the sectional area of the 220kV cables. The design is the responsibility of the bidder. The bidder is to indicate what the prices are based on.

269 Please confirm the cable laying method, direct buried or cable trench? Please provide the cable laying route.

The route is to be confirmed following contract award.The design is the responsibility of the bidder. The bidder is to indicate what the prices are based on.

270 Please confirm whether OPGW is contained in this cable line. OPGW shall not be provided for the underground cable feeders. However, underground fibre optic cable shall be.

271 A wind speed of 140 km/hr is indicated as the design wind speed. Please advise the height that this speed is measured and how often the speed is achieved for example once every year or every 10 years or 50 years.

Refer to the appropriate IECs and Eurocodes.

272 Please advise the incoming and outgoing voltages into the Athi River substation since in the Schedule 3A is titled 400KV while schedule 3B is titled 220KV. This will allow us to design for the correct transmission line.

The voltages are as stated in the Technical Specification.The price schedules reflect the details provided in Technical Specification for Transmission Line Works.

273 Please confirm the incoming and outgoing voltages into the Isinya substation. The voltages are as stated in the Technical Specifications.

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274 The generator to be provided at both Isinya and Athi River should this have capacity load for the construction of the substation and for the operation of the substation as well, or is this only to be sized for the operation and the contractor to provide his own size for the construction period. Can the generator the contractor will use remain at the substation as the substation standby power or should we provide a new unused generator at the commissioning.

The generator is for emergency substation operation only as per the specification. A new unused generator shall be supplied. The contractor is reponsible for providing all construction facilities. The Employer shall provide no facilities.

275 Does the contractor have to get the insurance from the Kenyan insurances company or the contractor is allowed to purchase insurance in other counties, the Chinese insurance company for example; does the Employer have any demand/restriction on the grade/level/qualification for the insurance company?

See Items 252 and 253

276 Does the Owner agree that: When damage/accident caused by the owner or the contractor happened, The insurance franchise which is not covered in the insurance according to the insurance terms, then the part (owner or Contractor) that made this damage/accident should be responsible for the cost of the franchise.

See Item 254

277 Defects Liability Period: Reference from Section IV General Condition 27.8• Does the Owner agree to define/set up the longest limitation for the Defects Liability Period? And how long the period will be?

See Item 255

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278 1.Wind speedLot A, Technical specifications for transmission line works,1.6 Service ConditionsFor design purposes a maximum wind velocity of 140km/h shall be assumed.Question According to IEC 60826 the reference wind speed VR can be determined from a statistical analysis of relevant wind speed data at 10 m above ground and with an averaging period of 10 min.Please provide the reference wind speed VR according to IEC 60826.

Please comply with the specification requirements.

279 The scope of transmission line worksAccording to the prices and quantities for TL works, the existing tension tower between existing transmission line and purposed transmission line shall not be dismantled and the foundation for the tension tower shall not be removed and reconstructed.Question The angle of the tension tower would have been changed after purposed transmission line being erected. So this tension tower and foundation shall not be used.

The existing towers will be designed and installed for both exisitng and new arrangements.

280 According to the item 10, item 13, item 15, item 16, of the attached Ketraco Minutes, we're waiting for the additional agenda issued by Ketraco.

All information has been made available to the bidders in addenda, Pre-bid minutes of meeting or clarifications.

281 According to the BDS, the bid security shall be Euro70,000, is this for two lots, or one lot.

The Bid Security shall be EUR 700,000 for each lot bid for.

282 According to the BDS, the bidder shall have executed 6 substations in 132kV or above, is this for two lots, or one lot.

The bidders shall demonstrate the experience requirements stated in the BDS for each Lot bid.

283 Please kindly clarify and extend the bid submission deadline upto 18th May, 2012 to enable us prepare more correct and competitive bid proposal.

Request rejected

284 Please clarify the number of the invitation for bid is two (2) lots, as mentioned in the bid data sheet.

Bidders can bid for one lot (Lot A or Lot B) or two lots (Lots A & B)

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285 Power TRTertiary winding using auxiliary load(10MVA)According to enclosed fill up data sheet, 1.18, Rated power at site condition is 200MVA.we assume each winding of capacity as below,HV winding[200MVA], LV winding[190MVA], TV winding[10MVA]Please confirm whether accept this concept.


286 33kV Overhead line connection workAs your Addendum3 about DNO substation, 33kV auxiliary transformer is added.And Connection work form 33kV overhead line to 33kV aux.TR is in this scope or out of scope. Please confirm.

All of the local supplies connection works from the existing 33kV line to the LVAC board are included within the scope.

287 Lot AIn the Technical specifications for Transmissions Line works Volume 1 Page 9 of 109, you have indicated that the 220kVLine Athi River to Embakasi is double circuit line with single Canary conductors. However, in the BOQ Volume 2 of 84, you have indicated in item 1.1 Six phases of quad lineConductors. Our interpretation is that the conductor to be used in this case should be Single canary not quad Lark nor quad Lark

Item 1.1 should read "six phases of single canary conductors".

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288 Lot BIn the Technical specifications for Transmission Line Works Volume 1 Page 8 of 9, you have indicated that the work to be done if for a 400kVLine operating at 220KV. But in the preamble Volume 2 Page 1 of 2 you have indicated that schedule 3 Ngong 220/66KV Transmission Line Works. In the BOQ of Volume 2 Schedule 3, there is no work for the 66KV line. And also there are no technical schedules or structures for the 66KKV line.

Overhead line works will be 400KV. Details similar to Lot A.

289 In the tender you have issue some foundations drawings for the different towers.Please provide us with all drawings for the different towers as requested by the tender.

Lot B will be similar but not identical to Lot A. Full details of towers and foundations will be provided to the sucessful bidder.

290 Is there any Optical differential protection for Athi River to Embakasi, Isinya to Suswa, Isinya to Rabai, Dandora to Juja Road, Dandora to Nairobi North, Dandora to Kamburu, Koma Rock to Dandora?

Following contract award it is the responsibility of the contractor to obtain this information with the help of the Employer.

291 What is the model of Dandora busbar differential protection? See Item 116292 As per clause 19.6.2.2, it was mentioned that highly expansive soils may exist

naturally, please check whether these types of soils are avialable in the proposed substation locations.


293 As per clause 19.16.8.1, it was mentioned that if sulphate levels below or excess 6.7 g/l, bitumen emulsion paint to be applied above capillary rise zone.whether this is encountered anywhere.

See Item 292

294 Indicative information about the depth of water table at the proposed substation locations.(name mentioned below)

See Item 292

295 Indicative soil strata/properties /soil investigation report for the 5 locations See Item 292

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296 Indicative soil resistivity at the proposed substation locations. If not available indicative data to be provided for design considerations

See Item 292

297 Type of earth mat prevalent (copper or GI Strip) It is the responsibility of the contractor to obtain this information after contract award.

298 What is the local practice for drain - RCC or Stone Pitching or we can go on our own based on cost considerations


299 Is the extension and modification of protection and control system at S/S Dandora part of the scope of work?

Yes

300 Does this extension and modification includes reconfiguration of existing protection and control system from ring bus topology to "breaker-and-a-third" topology?

Yes

301 We kindly ask you to provide details about the existing protection and control system in Dandora S/S.

Refer to the Bid Drawings provided in Appendix A.

302 General Note that the locations of the substations are attached to these clarifications.

303 General For Lot B Price Schedule No.3 - Ngong 400kV Transmission Line Works - the bidders shall provide unit CIP prices for all items within the price schedule, even where estimated quantities are stated as being zero.

304 General The height above sea level of the Ngong Substation is approximately 1880m.

END

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Ngong Substation Coordinate List

Easting Northing Description1 232984.691 9852660.157 A 2 233098.003 9852845.5 B3 233472.042 9852811.497 C4 233437.046 9852619.034 D

Isinya Substation Coordinate List

Eastings Northings Description1 258334 9804156 SS12 258334 9803743 SS23 259323 9803781 SS34 259344 9804194 SS4

NB: Both SS1 & SS2 Have same Easting Values

Athi River Substation Coordinate List

1 272441 9839251 PC322 272497 9839058 PZ23 272409 9838911 PZ34 272377 9838927 PZ45 272368 9838911 PZ56 272376 9838907 PZ67 272380 9838896 PZ78 272845 9838497 PZ289 272853 9838440 PZ29

10 272018 9838911 PZ5011 272988 9837911 PZ6012 272078 9839012 PZ6713 272132 9839029 PZ68