STATE OF CALIFORNIA, PETE WILSON,
Governor
January 14, 1998
RE: Variance Request #40 - Relocation of a combination block and check valve from station number 3109+26 to 3123+00 (a distance of 1,374 feet south) within The Old Road, Segment 2B.
Dear Mr. Shauers:
We have reviewed the above-referenced variance request and approve your request based on the following factors:
• The valve relocation has been requested to provide the space required to install the valve vault (16 feet wide) a minimum distance of one foot from existing underground pipelines (Mobil M-70 and a 24" SCE gas pipeline), a DOT requirement; the originally proposed valve location only provides 14 feet of room between the existing pipelines and the Pacific Pipeline due to terrain constraints.
• In accordance with Mitigation Measure SS-29**, valves shall be installed along the pipeline alignment at environmentally sensitive areas, areas of liquefaction/faulting/scour, and at pump stations. The subject block/check valve has been incorporated into the project design to minimize the spill of oil associated with a rupture of the pipeline due to seismic activity along the San Gabriel Fault. The proposed valve relocation would reduce the potential for a maximum of 560 additional barrels of oil from entering the nearest stream crossing (SC-49) approximately 1,300 feet south of the subject valve site. Therefore, potential spill impacts to the biological and hydrologic resources of the stream channel would be reduced.
• The following measures shall be implemented:
- All applicable mitigation measures for the project shall be implemented at the subject location.
- On-site storm drainage features shall be protected by installing temporary fencing to identify prohibition areas and/or installing and maintaining erosion control measures. Siting of fencing and/or erosion control measures shall be approved by the CPUC Environmental Monitor prior to excavation of the valve vault.
- Vehicle passage on The Old Road shall be maintained.
- Implementation of this variance in accordance with the provisions noted above shall be verified on a random basis by a CPUC/ANF Environmental Monitor.
Sincerely,
