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and a water tight, locking well cap with lock was installed on each well casing. The traffic boxes were typically set about an ' inch above the existing ground surface to help divert surface water away from the well . 3 . 3 . 2 Monitoring well Development Wells MW--4 through MW-6 were developed on June 18, 1992 . Each well was checked for floating product prior to development using a dedicated polyethylene bailer. No floating product or sheen was noted in any of the wells. Each well was developed by surging and using a 4-inch O.D. PVC ' bailer until the water was clear of sand, silt, and turbidity or no change in improvement was noted. Development water was stored on site in 55-gallon DOT steel drums. The drums were labeled to ' show contents, suspected contaminant, date filled, company name, contact person, and telephone number. ' 3 . 3 . 3 Monitoring Well Sampling Groundwater samples were collected from all 3 wells on July 1, 1992 . Prior to sampling, the wells were measured for depth-to- water to the nearest 0. 01 foot using an electronic Solinst water level meter. A minimum of 3 repetitive measurements were made for each level determination to ensure accuracy. Each well was checked for floating product using a dedicated polyethylene bailer; no floating product, sheen or odor was noted. Each well r was purged a minimum of 4 well volumes with a 4-inch O. D. dedicated PVC baler or until temperature, pH, and electrical ' conductivity of the purged water stabilized. After purging was completed, the water samples were collected with a 2-inch PVC disposal bailer. The samples were carefully decanted into preserved, clean 40 ml glass vials with teflon lined screw caps, immediately sealed, and labeled to include: ' date, time, sample location, pro3ect number, and sampler. The samples were immediately stored on ice for transport. to Trace Analysis Laboratory [a state of California Department of Health Services (DHS) certified laboratory] . The samples were ' accompanied by chain-of-custody documentation. See Appendix �? for waste handling and decontamination procedure, and quality assurance and quality control procedures (QA/QC) . ' The monitoring well purge water was stored on site in the 55 gallon DOT drums containing the development water. 3 . 3 . 4 Results of Groundwater Chemical Analyses , I Water samples from monitoring wells 'MW,4 , MW-5 , and MW-6 ,'were f' analyzed for TPHG (DHS Method) and BTEX (EPA Method 8020) . A trip blank labeled MW-7 (containing organic-free water) was, also I ' 6 , I I f ` I I d�e��"i I rl' I I