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cooler with ice. At the end of the day, the samples were deliv- ered to the laboratory. The three exploratory soil boreholes were grouted (with a 5% betonite-cement mixture) from the bottom up utilizing a Trimline to within a few feet of the surface. Concrete was used to fill the remaining holes to flush with the asphalt surface. As with the cuttings from the monitor well boreholes, all cutting from the exploratory soil borings were containerized into labeled 55 gallon steel drums. These drums were stored at the site pending receipt of the analytical results. The soil samples submitted for chemical analysis were transported under chain-of-custody to the WESTON Analytic ' s Stockton, Cali- fornia laboratory. The analytical suite included aromatic volatile organics by EPA Method 8020 and total petroleum hydro- carbons by Method 8015 modified for diesel . All chain-of-custo- dies are presented in this section. well Development On April 26, 1989, the monitor wells were developed by a combina- tion of swabbing and bailing using a CME-55 drill rig. Prior to development, no floating product was observed. Each well was first swabbed repeatedly, for approximately 20 minutes, then bailed. Approximately 40 gallons of water were bailed form MW-1, approximately 50 gallons of water was bailed from MW-2 and 25-30 gallons of water was removed from MW-3 . This development process removed the heavier materials "from the inside of the wells. For all wells, the effluent was relatively sediment free at the end of the development process. The swab and bailer were steam cleaned prior to first use and prior to use at each well to prevent cross contamination between wells. Well Surveying On May 10, 1989 , the monitor wells were surveyed by WESTON. The survey established elevations to the top of the PVC well casing at each well relative to a bench mark (Simplot BM#2) . Top of casing elevations are as follows: MW1 at 15 .20 feet; MW2 at 15 . 47 feet ; and MW3 at 16 . 29 feet. Groundwater Sam lin Groundwater samples were collected on May 10, 1989 . Prior to sampling an evaluation of the presence or absence of free float- ing product was made using both gasoline and water sensitive pastes. No floating product was observed. Depth to water and total depth measurements were also taken at this time concurrent with surveying of the wells. Using the depth to water and total well depth measurement, the volume of standing water in the well and the required purge volume was calculated and recorded on a