Laserfiche WebLink
Date September 6,2005 <br /> Quarter 3`d Quarter,2005 <br /> • ARCO QUARTERLY GROUNDWATER MONITORING REPORT <br /> Facility No 11191 <br /> Address 1469 East Hammer Lane, Stockton, CA <br /> ARCO Environmental Engineer Kyle Christie _ <br /> • Consulting Co/Contact Person URS/Vernon Elarth <br /> Consultant Project No 38466550 0A143 <br /> Primary Agency/Regulatory ID No San Joaquin County Environmental Health Department <br /> Assembly Bill 681 Status Property owned by Conoco Phillips <br /> WORK PERFORMED THIS QUARTER (Third 2005): <br /> 1 Performed quarterly groundwater monitoring and sampling <br /> 2 Prepared and submitted quarterly groundwater monitoring report <br /> WORK PROPOSED FOR NEXT QUARTER (Fourth 2005): <br /> 1 Perform quarterly groundwater monitoring and sampling <br /> 2 Prepare and submit quarterly groundwater monitoring report <br /> QUARTERLY RESULTS SUMMARY (Third 2005): <br /> • Current Phase of Project _ Monitoring <br /> Frequency of Groundwater Sampling MW-1 through MW-7, Quarterly <br /> Frequency of Groundwater Monitoring Quarterly <br /> Is Free Product (FP) Present on Site No <br /> FP Recovered This Quarter NA <br /> Cumulative FP Recovered to Date NA <br /> Approximate Depth to Groundwater 52 45 to 54 51 feet below ground surfac_e_(bgs) _ <br /> Direction of Groundwater Flow Northwest to Southwest <br /> Groundwater Gradient 0 01 to 0 02 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, MS/MSD results, and surrogate recoveries), the data are acceptable as reported by the laboratory <br /> with the following limitation <br /> • The elevated reporting limits were the result of dilutions performed by the laboratory in order to quantitate a <br /> target analyte <br /> DISCUSSION: <br /> Methyl tert-butyl ether (MEBE) and tert-butyl alcohol (IBA) were detected above laboratory reporting limits in <br /> groundwater samples collected from site monitoring wells this quarter MtBE concentrations in MW-3 decreased to <br /> the lowest level reported historically and TBA concentrations decreased Other analyte concentrations were generally <br /> consistent with previous sampling events <br /> K%Wproc"sV 5 RP ARC011 i 1915QuanerWOD5\3 QTR 05511191 GWMR 3Q05 doc Page 1 <br />