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Those soil samples selected for laboratory analysis were trimmed of excess soil, covered with Teflon tape and plastic end caps, and sealed with waterproof duct tape. Each sample was labeled, placed in a resealable plastic bag, and put into an ice-filled cooler for transport, by courier to the McLaren Analytical Laboratory in Rancho Cordova, California. Transport of the samples was conducted under chain-of-custody protocol. The monitoring wells were constructed in the 8-mch diameter boreholes by installing 2-inch diameter Schedule 40 flush-threaded PVC casing and 0 020-inch factory slotted screen. The screened interval extended from approximately 5.0 feet above first encountered groundwater to 10 0 feet into the shallow aquifer. The graded sand filter pack (#2/12 sand) was placed in the annular space from the bottom of the borehole, across the screened interval, to ' approximately two-feet above the top of the screened interval. Two feet of hydrated bentonite pellets were placed above the sand filter pack and the monitoring well sealed to the surface with portland cement. A protective traffic-rated EMCO-Wheaton well box and ' locking cap were installed at grade to secure the well Monitoring well construction practices were observed and approved by an inspector from the PHS/EHD. Monitoring well construction details are included in the boring logs in Appendix 1. The drill cuttings and fluids generated during drilling and sampling were contained in fifteen 55-gallon drums, labeled, and stored on-site. ' 3.3 Groundwater Sampling Procedures On November 12 and 13, 1992 the monitoring wells were developed. Depth to static water level was measured, and the wells were surged in 3 foot increments for ten repetitions to enhance the hydraulic communication between the transmissive zone and the filter pack A 2-mch diameter bailer was used to remove a majority of the fines that had settled in the casing prior to pumping. A minimum of 10 casing volumes were removed from each monitor well using a 2-inch diameter submersible pump set at 1-foot above the bottom of the casing. Temperature, pH, electric conductivity and turbidity were measured following the removal of each casing volume. Development was considered complete once ten casing volumes were removed and stabilization of the measured parameters was achieved On November 19, 1992 groundwater samples were collected from monitoring wells MW1 through MWS for laboratory analysis. Prior to sampling, the depth to static water level was measured, and by using a 2-inch diameter submersible pump, four casing volumes of groundwater were purged from each well Temperature, pH, electric conductivity and turbidity were measured following the removal of each casing volume. A disposable teflon ' bailer was used to collect groundwater samples once purging was complete. The contents of the bailer were then emptied into two 1-liter amber bottles for analysis by EPA Method 8015 Modified, into two 1-liter amber bottles for analysis by EPA Method 7421, and into four 40-milliliter VOA vials for analysis by EPA Method 602 The sample containers were capped immediately, labeled, packed in foam rubber and placed into an ice-filled cooler with accompanying tip blanks for transport,by Federal Express, to the McLaren Analytical Laboratory in Rancho Cordova, California. Transport of the samples was conducted under 111B1cd1 8