Laserfiche WebLink
California Refonal Water Quality Antrol Board - <br /> Central Valley Region ` <br /> Robert Schneider,Chair <br /> Winston H.Hickox Gray Davis <br /> Secretaryfor Sacramento Main Office Governor <br /> Environmental Internet Address: http://w .swrcb.ca.gov/mgcb5 <br /> Protection 3443 Routier Road,Suite A,Sacramento,California 95827-3003 - <br /> Phone(916)255-3000•FAX(916)255-3015 <br /> 4 October 2001 <br /> Ms. Julie Raining <br /> Environmental Affairs <br /> Georgia-Pacific Corporation <br /> P.O. Box 105605 <br /> Atlanta, GA. 30348 <br /> WORKPLAN FOR ADDITIONAL SOURCE AREA ASSESSMENT, FORMER GEORGIA- <br /> PACIFIC CORPORA TON TRACY CHEMICAL PACKAGING PLANT, 75 WEST VALPICO <br /> ROAD, TRACY, SAN JOA QUIN COUNTY <br /> We have reviewed the 13 September 2001 Workplan For Additional Source Area Assessment, Former <br /> Georgia-Pacific Corporation Tracy Chemical Packaging Plant, 75 West Valpico Road, Tracy, San <br /> Joaquin County(Workplan). The objectives of the proposed investigation are to assess whether <br /> chloroform beneath the waste water basin is contributing to groundwater contamination, characterize the <br /> vertical extent otvolatile organic compounds (VOCs), and assess the feasibility of in-situ remediation. <br /> Remedial efforts at this site date back to 1985. Chloroform impacts to groundwater resulted from a July <br /> 1984 discharge of 12% sodium hypochlorite to the waste water basin. Groundwater monitoring at the <br /> site is currently performed on a semi-annual basis. There are 18 groundwater monitoring wells on site. <br /> Three, source area wells (BC-2, BC-3, and BC-4)have been sampled on an intermittent basis due to an <br /> insufficient volume of groundwater in the wells since 1991. Chloform concentrations in groundwater <br /> have not been characterized in monitoring wells BC-2 to BC-5 since January of 2001 for the same <br /> reason. <br /> The Workplan proposes using a cone penetrometer test(CPT) rig to advance three borings to 70 feet <br /> below ground surface (bgs), within the former storm water basin. Soil samples will be collected at five <br /> foot intervals. Groundwater samples will be collected using a Hydropunch® sampler. Soil and grab <br /> groundwater samples will be analyzed for VOCs. hi addition, grab groundwater samples will be <br /> analyzed for selected geochemical parameters to assess the feasibility of in-site remediation techniques. <br /> Our comments on the Workplan are listed below. <br /> General Comments <br /> 1. The Workplan proposes sampling to 70 feet bgs at a site where chloroform has been detected in <br /> wells screened to 85 feet bgs. Contingencies should be developed that provide a strategy for <br /> investigating beyond the 70 feet bgs in the event that chloroform is detected in soil or <br /> groundwater samples collected from 70 feet bgs. Precautions should be taken to safe guard <br /> deeper soils from vertical cross-contamination during drilling. <br /> California Environmental Protection Agency <br /> 01 Recycled Paper <br /> The energy challenge facing California is real. Every Californian needs to take immediate action to reduce energy consumption. <br /> For a list of simple ways you can reduce demand and cut your energy costs,see our Web-site at http://www.swrcb.ca.gov/mgcb5 <br />