DEPARTMENT Infrastructure
AGENDA NO.
12a
MEETING DATE
September 27, 2022
APPROVAL:
COMMISSION
SECRETARY
Donna Hood
AGENDA ITEM
Public Utilities Commission
City and County of San Francisco
Construction Modification: Consent Calendar
Contract Manager: Tim Parkan
Approve Increase to Construction Cost Contingency for Contract No. HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation
Summary of Proposed
Commission Action:
Approve an increase of $600,000 to the Contract cost contingency for Contract No. HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation , with Big Valley Electric , to accommodate differing field conditions, address design revisions, and fund additional hazardous material abatement; and authorize the General Manager to approve future modifications to the Contract for a total Contract amount of up to $4,253,575, with no change to Contract duration.
Background: Moccasin Powerhouse was completed and placed in operation on January 27, 1969. The facility's rated capacity is 100,000 KVA (thousand-volt amps). The powerhouse uses two 13.8-230Y/132.9- 115Y/66.5 kV generators and two, 3- phase 57.5 MVA (mega-volt amps) transformers at any given time, with a third spare transformer.
Delivery of Hetch Hetchy water is dependent on the operation of both generators, which rely on the three transformers. All three transformers have exceeded their service life. T wo of the three transformers are manufactured by Toshiba and the third is manufactured by General Electric/Prolec.
On April 27, 2021, by Resolution No. 21-0062, the Commission awarded Contract No. HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation . The original contract amount was $3,321,432, and the original contract duration was 716 consecutive calendar days.
Description of Scope of
Work:
The contract work location is at the Moccasin Powerhouse in Tuolumne County. The contract work consists of:
• Replacing two transformer foundations including oil
containment.
• Installing two City-furnished transformers.
• Making improvements to the grounding system.
Contract: HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation Commission Meeting Date: September 27, 2022
• Performing protection studies and determining relay settings. • Commissioning new protection relays.
• Terminating all connections to the transformers.
• Terminating and testing all monitoring and protective wiring. • Installing two new transformers in consecutive years, W inter 2021/2022, and Winter 2022/2023.
• Testing three old transformers in order to keep the one best suited as a spare (the contractor will then take possession of and remove the two out-of-service transformers).
Changes and
Modifications to the
Contract:
Modification No . 1 was issued decreasing the contract amount by $313,256 to install the correct test switches and 18-point terminal blocks in the protection relay panel, to perform core drilling in the powerhouse floor for routing relay panel cables, and to reflect a credit for not applying intumescent coating from the lattice tower (since it was determined
that National Fire Protection Association (NPFA) 850
requirements for the fire protective coating are not mandatory for the Moccasin Powerhouse), for a total Contract amount of $3,008,176, with no change to the Contract duration.
Modification No. 2 was issued increasing the Contract amount by $238,848, within the original cost contingency, to change the wire size for the 230kV side current transformers, redesign the transformer oil containment and foundation, install an oil pump, change the foundation anchor bolts to a heavy duty design, modif y the protection systems for the transformers, and revise the AutoCAD electrical drawings , for a
total contract amount of $3,247,024, with no change to the contract duration.
Modification No. 3 was issued increasing the Contract amount by $49,849 within the original cost contingency, to refurbish the 13.8 kV non-segregated bus for Generator Step-up Transformer (GSU) No. 1, for overrun on Bid Item 13 – Contingency Allowance for Hazardous Material Testing and Abatement , to reflect a credit for not having to provide a City construction trailer, and to provide oil containment for GSU No. 1 for a period of time after its removal, for a total contract amount of $3,296,873, with no change to the contract duration.
Modification No. 4 was issued increasing the Contract amount by $21,073, within the original cost contingency, to provide as -built drawings for omitted metering circuits, to furnish and install omitted GSU control cables, to furnish and install omitted relay cables, to modify the 13.8kV non-segregated bus duct, to add new braids, and to perform lead abatement, for a total Contract amount of $3,317,946, with no change to the Contract duration.
Requested Increase to Contract Cost Contingency
Contract: HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation Commission Meeting Date: September 27, 2022
An increase of $600,000 to the existing Contract cost contingency is being requested to accommodate differing field conditions, address design revisions, and fund additional hazardous material abatement, for a total C ontract amount of up to $4,253,575, with no change to the Contract duration.
A significant change to the transformer foundation and oil containment structure w as needed due to lack of identification of underground utilities during design along with discovery of additional unforeseen buried utilities , resulting in design modifications that required customized shoring in a confined work area. A sump pump needed to be added to the oil sump drain to meet elevation requirements . The budget for Bid item 13, Contingency Allowance for Hazardous Material Testing and Abatement was exhausted during the GSU No. 1 installation due to the need to recondition equipment including lead abatement. Additional modifications included wiring and control changes for the cooling fans, owner requested display panels, and more AutoCAD electrical drawings.
While this increase in contingency is being requested for these cost s that are only applicable to the installation of GSU No. 1, it is forecasted that similar changes may be necessary in the future for the installation of GSU No. 2.
Funding, Budget &
Costs:
Funding: Project No. 10014086, Moccasin Powerhouse Generator and Step Up Transformer Rehabilitation
Original Contract Amount: $3,321,432
Original 10% Cost Contingency: $332,143
Requested Additional Cost Contingency: $600,000
Total Revised Contract Cost Limit: $4,253,575
Schedule: Notice-to-Proceed Date: June 7, 2021
Original Contract Duration: 716 consecutive calendar days Original 10% Duration Contingency: 71 calendar days
Total Contract Duration Limit: 787 consecutive calendar days
Environmental Review: On February 18, 2021 , the San Francisco Planning Department determined the Project to be categorically exempt from environmental review under California Environmental Quality Act Section (CEQA) Guidelines Section 15303, Class 3 (New Construction or Conversion of Small Structures) under Case Number 2020-011950ENV.
Modifications to the P roject include revisions to the transformer foundation, along with minor changes such as demolition of existing asphalt. On September 15, 2022, under Case Number 2020- 011950ENV and
pursuant to San Francisco Administrative Code
subsection 31.08(i), the Planning Department determined that these modifications are not substantial, and the modified project remains Contract: HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation Commission Meeting Date: September 27, 2022
categorically exempt under CEQA and does not require further environmental review.
The exemption and determination of no substantial modification can be found here: https://sfpuc.sharefile.com/d-
s984d756c63b445cd98e2bc69ae00e4ad
Compliance with
Chapter 14B: Local
Business Enterprise
Utilization and Non-
Discrimination In
Contracting Ordinance:
The Contract Monitoring Division established a Local Business Enterprise (LBE) subcontracting participation requirement of 3% for this contract. The contractor committed to a LBE subcontractor participation of 18.93% with its bid submittal.
Result of Inaction: A delay or denial of approving this request will prolong the immediate need to replace the second of two GSU’s beyond their service life. The first GSU was replaced in winter 2021/2022. Power generation and Hetch Hetchy Water delivery are dependent on both GSU’s being in service. GSU No . 2 replacement will coincide with the Winter 2022/2023 Mountain Tunnel Outages, reducing risk for water delivery to the Bay Area users. Unscheduled outages for equipment failure may result in lost power revenue, interruptions to water delivery, and /or more expensive emergency repair contracts.
Recommendation: San Francisco Public Utilities Commission staff recommends that the Commission adopt the attached resolution.
Attachment: CMD Memo
Contract: HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation Commission Meeting Date: September 27, 2022
PUBLIC UTILITIES COMMISSION
City and County of San Francisco
RESOLUTION NO.
WHEREAS, The San Francisco Public Utilities Commission (SFPUC) needs to replace the second of two generator step-up unit transformers (GSUs) located at Moccasin Powerhouse that is beyond its service life, to provide reliability and redundancy in delivery of Hetch Hetchy water to its customers and meet power generation commitments; and WHEREAS, On April 27, 2021, by Resolution No. 21-0062, the Commission awarded Contract No. HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation to Big Valley Electric; and
WHEREAS, The construction contract Notice-to-Proceed date was June 7, 2021; and WHEREAS, The original contract amount was for $3,321,432, and the original contract duration was 716 consecutive calendar days; and
WHEREAS, The SFPUC, by Modification Nos . 1 to 4, increased the Contract amount to $3,317,946 for modifications to the foundation and oil containment system, installation of an oil sump pump, additional budget for Bid item 13, Contingency Allowance for Hazardous Material Testing and Abatement , reconditioning of equipment including lead abatement , changes to the wiring and control systems for the cooling fans , addition of displays, additional AutoCAD electrical drawings, reflection of credit for not applying fire protection intumescent coating and not providing a construction trailer; and
WHEREAS, An increase of $600,000 to the Contract cost contingency is being requested to accommodate differing field conditions, address design revisions, and fund additional hazardous material abatement; and
WHEREAS, Contract Monitoring Division established a Local Business Enterprise (LBE) subcontracting participation requirement of 3% for this contract, and the contractor committed to a LBE subcontractor participation of 18.93% with its bid submittal; and WHEREAS, Funds are available from Project No. 10014086, Moccasin Powerhouse Generator and Step Up Transformer Rehabilitation; and
WHEREAS, On February 18, 2021, the San Francisco Pla nning Department determined the Project to be categorically exempt from environmental review under California Environmental Quality Act Section (CEQA) Guidelines Section 15303, Class 3 (New Construction or Conversion of Small Structures) under Case Number 2020-011950ENV; and WHEREAS, On September 15, 2022, under Case Number 2020-011950ENV and pursuant to San Francisco Administrative Code subsection 31.08(i), the Planning Department determined that modifications to the Project proposed under this action are not substantial, and the modified project remains categorically exempt under CEQA and does not require further environmental review; now, therefore, be it
RESOLVED, That this Commission hereby a pproves an increase of $ 600,000 to the existing Contract cost contingency for Contract No. HH-1003R, Moccasin Powerhouse Generator Step Up Transformer Installation, for a total contract cost contingency amount of up to $932,143; and be it
FURTHER RESOLVED, That this Commission hereby authorizes the G eneral Manager, or the General Manager’s designee, to consider, and, if appropriate, to approve any future modifications to the Contract amount for a total Contract amount of up to $4,253,575, with no change to the Contract duration.
I hereby certify that the foregoing resolution was adopted by the Public Utilities Commission at its meeting of September 27, 2022
Secretary, Public Utilities Commission