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DESCRIPTION OF SAMPLING, HANDLING AND PREPARATION PROCEDURES Auger flights were hollow-stem types with an inside diameter of 3 . 25 inches and an outside diameter of 6. 0 inches . Individual ' auger flights were five feet in length. Soil samples were collected at five foot intervals . A retractable plug prevented soil from entering into the auger flights during the boring pro- cess . The plug, which is inserted or retrieved by a wireline, is ' at the end of a 140 pound drive hammer . When a target depth is reached, a Modified California Sampler is placed at the bottom of the hammer and lowered by wireline to the bottom of the boring . ' The sampler is then driven into the soil by repeatedly raising and dropping the hammer 30 inches until the sampler has been advanced 12 inches . This driving action forces relatively undisturbed soil into the sampler barrel . Details of the com- ponents of the Modified California Sampler are described below. Following the driving operation , the hammer and sampler are retrieved from the boring and separated; soil is removed from the ' sampler and prepared for shipment to an analytical laboratory. The Modified California Sampler consists of an outer sampler ' barrel and an inner, thin-walled set of rings . As soil is forced into the sample barrel by the driving action described above, a soil sample is collected in the inner rings. For this applica- tion, two 6-inch long by 2. 5-inch diameter brass rings were used. After retrieval from the boring and subsequent detachment from the hammer, the sampler was dismantled and the inner rings con- taining the soil sampler were removed. The lower ring was sealed ' by covering the ends with aluminum foil, placing plastic caps on each tube end, and securing the caps with duct tape. Each sample was then labeled and placed in an ice chest for cold storage for shipment to an analytical laboratory. To avoid cross-contamination between samples and boreholes , the Modified California Sampler and the brass ring inserts were cleaned before each use . The sampling equipment was washed with an aqueous solution of trisodium phosphate, rinsed twice with tap water and allowed to air dry. ' Each soil sample collected was analyzed for possible hydrocarbon contamination by use of an organic vapor meter (Gastechtor model ' 1314 ) . A portion of the sample was placed in a sealable ( ziplock) plastic bag . After the bag had been sealed for a mini- mum of 5 minutes the sample was "sniffed" and the meter readings ' (parts per million ) recorded on the boring log. The model 1314 Gastechtor-Hydrocarbon Surveyor is a battery-powered instrument that can detect and indicate concentrations of combustible gas or vapor in air , in the explosibility and parts per million ranges . Samples under test are drawn continuously by means of a built-in pump and analyzed for combustible gas on a heated catalytic pla- tinum element. This instrument will respond to at least 23 dif- ferent gases including various petroleum products . Results of the Gastechtor are given in parts per million and are used only as a qualitative field measure of potential soil contamination .