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Table 1-1 Sampling Schedule Quarter Momtor Wells to be Sampled ' First MW-2,MW-2A and MW-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 Fourth MW-2 MW-2A,MW-3A,MW-4,MW-5,MW-6,MW-7,and MW-9 2.0 FIELD SAMPLING SUMMARY ' Groundwater samples were collected from monitor wells MW-2, MW-2A, and MW-9 (Figure I-1) on September 1512004 In addition, an equipment blank water sample was collected and submitted for analysis Groundwater sampling field data sheets for the monitor wells are presented in Appendix B ' Prior to well purging, water levels were measured in all wells on September 151, 2004 to collect data for potentiometnc contouring 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 attached to a disposable discharge hose was then lowered into the well and 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 water were measured and recorded on a sampling data sheet The pump was then removed and a disposable bailer was lowered into the well for the collection of groundwater samples for benzene, toluene, ethylbenzene, and total xylene (BTEX), and for total petroleum hydrocarbons as gasoline (TPH- g) analysts The groundwater sample was transferred into 40-mtlliliter (mL) glass sample containers ' Sample containers containing air bubbles were discarded and recollected 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 The pump used to purge and sample the wells was thoroughly cleaned prior to each use by placing it into a container of tap water with non-phosphate detergent and washing the outside of the pump Dedicated ' purge tubing is used for each well Purge water from MW-2 and MW-2A was stored in 55-gallon drums in the garage located at 100 N ' Hunter Street and meets the requirements for transfer and disposal at a licensed treatment facility The groundwater samples were analyzed by EPA Method 8015E/802113 for BTEX and TPH-g Groundwater sample analyses were performed by Sequoia Analytical Laboratory in Sacramento, California Additionally, WESTON collected a sample of water stored in a holding tank staged at the loading dock of the San Joaquin Human Services Agency building The holding tank is used to store ' purge water collected from wells MW-3A, MW-4, MW-5, MW-6, MW-7, and MW-9 The sample was analyzed by EPA Method 801513/802113 for BTEX, TPH-g, and methyl tertiary-butyl ether (MTBE) The sample was collected in an effort to characterize water contained in the holding tank for discharge to the sanitary sewer at a later date 2