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1.0 FIELD PROCEDURES 1.1 Locating-Underground Utilities Prior to the commencement of work on site, Delta researched the location of all underground utilities with the assistance of Underground Service Alert (USA) USA contacted the owners of the various utilities ' in the vicinity of the site to have the utility owners mark the locations of their underground utilities Work associated with the drilling and monitoring well installation was preceded by hand-digging of the soil borings to a minimum depth of 5 feet to avoid contact with underground fuel distribution lines, vent lines and other unmarked utilities 1.2 Drilling and Soil Sampling Procedures ' Soil borings and soil sampling were performed under the direction of a Delta field geologist The soil borings were advanced using a truck-mounted drill rig utilizing hollow-stem augers. Soil sampling was done in general accordance with procedure ASTM 1586-84 Using this procedure, a 2-inch inside-diameter California-type split barrel sampler is driven into the soil in advance of the augers by a 140-pound weight repetitively falling 30 inches Three new steam-cleaned brass tubes were inserted into the sampler before each 5--foot drive After an initial set of 6-inches, the number of blows required to drive the sampler an additional 12 inches is recorded The blow count value is used as an empirical measure of the relative density of cohesionless soils and the consistency of cohesive soils. ' Upon recovery of the sampler, the soil from the bottom brass tube was placed into a glass far and covered with aluminum foil for later screening with a photoionization detector (PID) The soil from the drive shoe of the sampler and from the top brass tube was used for classification The soil retained in the ' middle brass tube was saved for chemical analysis The ends of this brass tube were covered with teflon tape, capped with a plastic end cap, taped with duct tape, placed in a plastic ziplock bag and stored in ' a cooler at approximately VC for transport to the laboratory 1.3 Decontamination Protocol To reduce the chances of cross contamination between boreholes, all down-hole drilling equipment was ' cleaned between each soil boring To reduce cross contamination between samples, the split-barrel sampler was washed in a soap solution and double rinsed between each sampling event Wash water and ' rinsate solutions used for decontamination were contained in a 55-gallon drum for later disposal according to state and local regulations I ' RPT 112 JDM