ARCHIVED REPORTS XR0001302 - Laserfiche WebLink

Home Browse Search

i Atlantic Richfield Company 2 Former ARCO#4493 205 North Center Street,Stockton CA August 22 2002 f� the Shell site has since been discontinued and monitoring wells were abandoned The site and neighboring properties are owned by the City of Stockton and have been redeveloped for the Weber Point and Weber Block redevelopment projects On February 10 through 12, 1999, SECOR installed groundwater monitoring wells MW-1 through MW-4 at the site Analytical results of groundwater samples collected from the wells indicated that groundwater downgradient of the former product islands had been impacted by gasoline hydrocarbons On February 24, 1999, four 12,000-gallon double-walled fiberglass underground storage tanks (USTs) and associated product lines were removed from site Soil samples collected from beneath the former USTs and product lines indicated that petroleum hydrocarbons had impacted the soil beneath the site On April 13, 1999, one 300-gallon single-walled steel waste-oil tank was removed from the site Soil samples collected from the waste-oil tank pit did not contain detectable volatile organic compounds (VOCs) In May and June, 2000, SECOR conducted an investigation that included the drilling of four borings and the installation of three groundwater monitoring wells On May 8, 2000, one continuous core soil boring (B-1) was completed at the site by Precision Sampling of San Rafael, California Soil boring B-1 was advanced to 60 feet below ground surface (bgs) using Precision Sampling's direct push Enviro-Core sampling system Soil boring B-1 was continuously cored and groundwater"grab" samples were collected at depths of 30 feet, 45 feet, and 60 feet bgs On June 2, 2000, three groundwater monitoring wells (MW-5 through MW-7) were installed downgradient of the site by V&W Drilling of Isleton, California Wells MW-5 through MW-7 were installed to a total depth of 25 feet bgs, and were screened from 5 to 25 feet bgs Results of this investigation indicate that the hydrocarbons had impacted water as deep as 60 feet bgs onsite, and that the lateral extent of the plume was undefined Currently, wells MW-1 through MW-7 are sampled quarterly Depth to groundwater beneath the site has ranged from 11 to 13 feet below ground surface (bgs), and groundwater flow has been to the east-southeast at gradients ranging from 0 003 to 0 008 ft/ft ASSESSMENT ACTIVITIES AND FINDINGS Site-Specific Health and Safety Plan As required by the Occupational Health and Safety Administration (OSHA) Standard "Hazardous Waste Operations and Emergency Response" guidelines (29 CFR 1910 120), and by California Occupational Health and Safety Administration (Cal- OSHA) "Hazardous Waste Operations and Emergency Response" guidelines (CCR Title 8, Section 5192), SECOR prepared a Site-Specific Health and Safety Plan for field work I\ARCO\44931Reports%DualWell-Rpt doc