Laserfiche WebLink
Date: October 21,2004 <br /> Quarter: 3rd Quarter,2004 <br /> ARCO QUARTERLY GROUNDWATER MONITORING REPORT <br /> Facility No.: 5450 <br /> Address: 1617 West Fremont Street, Stockton, CA <br /> ARCO Environmental Engineer: Paul Supple <br /> Consulting Co./Contact Person: URS/Jeffrey Brooks <br /> Consultant Project No.: 38466523.01-058 <br /> Primary Agency/Regulatory ID No.: San Joaquin County Environmental Health Department <br /> Assembly Bili 681 Status: Property owned by Atlantic Richfield Company <br /> WORK PERFORMED THIS QUARTER (Third 2004): <br /> 1. Performed quarterly groundwater monitoring and sampling. <br /> 2. Prepared and submitted quarterly groundwater monitoring report. <br /> WORK PROPOSED FOR NEXT QUARTER (Fourth 2004): <br /> 1. Perform quarterly groundwater monitoring and sampling. <br /> 2. Prepare and submit quarterly groundwater monitoring report. <br /> 3. Complete Sensitive Receptor Survey. <br /> . QUARTERLY RESULTS SUMMARY (Third 2004): <br /> Current Phase of Project: Monitoring _ <br /> Frequency of Groundwater Sampling: MW-2 through MW-4 sampled quarterly <br /> Frequency of Groundwater Monitoring: Quarterly <br /> Is Free Product (FP) Present Onsite: No <br /> Current Remediation Techniques: Natural attenuation <br /> Approximate Depth to Groundwater: 11.46--11.61 feet below ground surface (bgs) <br /> Groundwater Flow and Gradient: Southwest @ 0.002 feet/foot(ft/ft) _ <br /> ANALYTICAL DATA REVIEW: <br /> Based on the review of the analytical and hardcopy data (chain-of-custody records,blanks, dilutions,holding times, <br /> LCS/LCSD results, MSIMSD results, and surrogate recoveries), the data are acceptable as reported by the <br /> laboratory. <br /> DISCUSSION: <br /> Total xylenes and methyl tert-butyl ether (MtBE) were detected above laboratory reporting limits in groundwater <br /> samples collected from site monitoring wells this quarter. In MW-2, total xylenes were detected just above <br /> laboratory reporting limits for the first time historically and MtBE concentrations continued to decrease. MtBE <br /> concentrations in MW-4 increased relative to previous sampling events. No other analytes were detected above <br /> laboratory reporting limits. <br /> KAWpro m'35 BP ARCCY0545MQuen W QTR 005450 GWMR 3Q04.dm Page 1 <br />