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Quarterly groundwater sampling has been conducted since 1996. This report is the third quarter 2001 groundwater monitoring report which represents the first report in the Phase IX groundwater sampling effort and presents the results of continued groundwater sampling following the schedule presented in Table 1-1. Table 1-1 Sampling Schedule t i U Quarter Monitor Wells to be Sampled — -2 MW-2A and MW-9 MW , M 9 Second MW-2,MW-2A,MW-3A, MW-4,MW-6,MW-7 and MW-9 ' Third MW-2, MW-2A and MW-9 i Fourth MW-2, MW-2A,MW-3A, MW-4, MW-5,MW-6,MW-7, and MW-9 j 2.0 FIELD SAMPLING SUMMARY Groundwater samples were collected from monitor wells MW-2, MW-2A, and MW-9 (Figure I-I) on k October 11, 2001. In addition, the holding tank was sampled and an equipment blank was collected. Groundwater sampling data sheets for the monitor wells are presented in Appendix B. -� Water levels in all wells were measured on October 11, 2001. The standing water volumes within wells scheduled for sampling were calculated using water levels measured in each well at the time of sampling and total well depths. A submersible pump was used to purge three well casing volumes from each of the monitor wells. At the beginning and during the purge process,the temperature,pH, and specific conductance of the purge r water were measured. This information was recorded on a sampling data sheet. Groundwater samples for benzene,toluene,ethylbenzene,and xylene(BTEX)and for total petroleum hydrocarbons as gasoline(TPH- G) analysis were collected from the wells with a disposable bailer and nylon string. The groundwater samples were transferred into 40 ml glass sample containers. Sample containers were checked for air bubbles. The sample containers were sealed in a plastic bag,placed with ice in an insulated chest,and logged on a chain-of-custody form for delivery to the analytical laboratory. x The pump used to purge and sample the wells was thoroughly cleaned prior to each use by placing it into a container oftap water and washing the outside of the pump. The disposable hose was discarded after purging each well. r � Purge water from monitor well MW-9 was stored in a holding tank located at 222 E.Weber Avenue. When full,the water in this tank will be sampled and,if acceptable,will be discharged to the sanitary sewer under �- a permit from the City of Stockton Department of Municipal Utilities. Purge water from MW-2 and MW-2A y LSPROJFM\SANJOQ\HSA51Q01RPT.WPD 2 _