Laserfiche WebLink
California �gional Water Quality Con l Board <br /> Central Valley Region <br /> Karl E. Longley,SCD,P.E.,Chair <br /> Linda S.Adams Arnold <br /> Secreta or Ib85 E Street,Fresno,California 93746 <br /> ryf Phone(559)445-5116•FAX(559)445-5910 5chwGoverovernegger <br /> EnvironmentalPhone <br /> Protection http://www.waterhoards.ca.govleentralvalley <br /> TO: Clay Rodgers FROM: C. Dean Hubbard <br /> Senior Engineering Geologist Engineering Geologist <br /> P. G. N 7 <br /> SIGNATURE: <br /> Shelton R. Gray <br /> DATE: 6 August 2009 SenjQr. Engineering Geologist <br /> SIGNATUR L:0' ��s <br /> SUBJECT: CONSIDERATION OF REQUEST FOR NO FURTHER ACTION REQUIRED <br /> DETERMINATION, MOUNTAIN HOUSE DEVELOPMENT SITE #5, WEST <br /> BYRON ROAD, MOUNTAIN HOUSE, SAN JOAQUIN COUNTY <br /> Rationale: Crude oil affected soil and groundwater has been delineated. Affected soil is <br /> confined to an area of approximately 60 by 75 feet, and defined vertically by samples <br /> containing no detectable concentrations of petroleum hydrocarbons from an approximate <br /> depth of 32 feet below ground surface (bgs). The area of affected groundwater is defined <br /> as having slightly larger dimensions of approximately 75 by 125 feet. The affected area of <br /> soil and groundwater is located beneath active pipelines and West Byron Road, within the <br /> highway right-of-way (ROW) easement and utility corridor. Future site use is anticipated to <br /> continue as the highway ROW and/or a utility corridor. <br /> An environmental risk screening evaluation (ERE) completed in 2008, considered a <br /> construction/trench maintenance worker the most likely potential future exposure. Based <br /> on Screening for Environmental Concerns at Sites with Contaminated Soil and <br /> Groundwater, Interim Final, San Francisco Regional Water Quality Control Board, May <br /> 2008, residual concentrations of crude oil remaining at the site are less than environmental <br /> screening levels (ESLs) for a construction/trench worker scenario. <br /> Consistent with State Water Resources Control Board (SWRCB) Resolution No. 92-49, <br /> Section IIIA through C, Science Applications International Corporation (SAIL) evaluated <br /> alternative cleanup technologies and found that technologies other than natural attenuation <br /> would be ineffective, infeasible, and costly since the affected area is beneath West Byron <br /> Road and the active pipelines. <br /> Issues: In 2001, crude oil affected soil was discovered in the vicinity of historical Tidewater <br /> Associated Oil Company pipelines and the Old Valley Pipelines which cross the property. <br /> The pipelines were utilized by Chevron predecessors to transport crude oil from Kern <br /> California Environmental Protection Agency <br /> 0d Recycled Paper <br />