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cieotogieat Technics Inc. _ Purdom&Bettencourt Page 2 SGWI Report Project No.: 9542 September 7,2001 analysis. The remainder of the sample was used frn eolo is were capped with plastic end caps, labeled and placed ia cooler at logging.0 Celsiules s forltransport to the laboratory following Chain of Custody protocol. The GeoProbe borings were advanced t 24- feet at 5-foot intervals for geologic logging and laboratory ana yeses: Soil samples were The 15-foot soil sample from each borehole was submitted to Castle Analytical in Atwater, CA for analysis. Since only selected samples were to be submitted for laboratory analysis, a screening process was used to gather additional information through field observation. This information was used to determine which samples were to be analyzed. The following characteristics were noted in the screening process: • sediment type, especially grain size and clay content • moisture content • visible evidence of contamination, i.e., color change due to reduction of iron or discoloration from hydrocarbons and other pollutants • readings above background on an organic vapor meter (OVM), a portable photo ionization detector that uses a 10.0 eV lamp to detect hydrocarbonrange compounds. Boring logs, providing sediment description using the USCS and field observations, were maintained by Michael Niemi, a geologist for GTI: The boring logs are included in Appendix C. II� 1.2 Groundwater Sample Collection r l Upon reaching the bottom of the hole, a hydropunch type sample tool was used to collect a groundwater sample from each borehole. The samples were collected by use of a Watera t type sampling tube and gently transferred into 40-mL VOAs. The bottles were capped, inverted, tapped, and checked for headspace bubbles. The bottles were then labeled and placed in a chilled cooler for transport to the laboratory following Chain of Custody protocol. Clean surgical gloves were worn at all times in handling of the sample and sampling equipment. 1.3 Laboratory Analyses Soil One soil sample from each borehole was submitted to Castle Analytical of Atwater, CA (State Certified Laboratory #2079). They were analyzed for the following: • Benzene, Toluene, Ethyl Benzene and Xylene (BTEX) by EPA method 8020 •. Methyl tertiary Butyl Ether(MTBE) by EPA method 8020 • Total petroleum hydrocarbons as gasoline (TPH-G)-by EPA method 8015/8020 is