SITE INFORMATION AND CORRESPONDENCE

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Kennedy/Jenks Consultants A preliminary site assessment was performed in November 1992. The work included a review of available agency records, installation of five groundwater monitoring wells, and analysis of soil and groundwater samples from each well. Static depth to water was established at approximately 30.5 feet below the ground surface, with a groundwater gra- dient toward the northeast. Soil analysis again detected petroleum hydrocarbons at depths of 25 and 30 feet in four of the five well borings. No petroleum hydrocarbons were detected in any of the borings at depths of 15 to 20 feet. Trace concentrations of hydrocarbons and/or BTEX were detected in four of the five groundwater monitoring wells. Quarterly sampling of the on-site monitoring wells was performed in June, September, and December of 1993. Water levels rose four feet from a depth of approximately 30.5 to 26.5 feet between November of 1992 and June of 1993, saturating most of the previously impacted soil on the site. Petroleum hydrocarbon and particularly benzene concentrations in groundwater increased. Groundwater gradients were consistently toward the northeast at slopes ranging from approximately 31 to 42 feet per mile. In October 1993, an evaluation of remedial alternatives for petroleum impacted soil on the site was performed. The scope included eight additional soil borings and one pilot soil vapor extraction well. The results of the soil sampling showed detectable concentrations of petroleum hydrocarbons in the soil at a depth of 23 to 28 feet across the site. 3.2 Site Activities Site activities will consist of a soil, soil vapor, and groundwater sampling program which includes collection from a total of seven sampling sites, five discrete sampling locations east of the site, and two locations on-site (see Figure 1). Soil vapor samples will be collected and analyzed from depths of 16, 21, and 26 feet below the ground surface at each sampling location. A grab groundwater sample will also be collected and analyzed from each sampling point. Soil samples will be collected from each borehole. Any addi- tional work that will include intrusive investigations will require an activity-specific health and safety addendum to this plan. 4.0 SAFETY AND HEALTH RISK EVALUATION 4.1 Potential Physical Hazards Field personnel should be cognizant of potential physical hazards associated with use of heavy equipment and electrical equipment during field operations. Appropriate precautions include the following: • ANSI-approved hardhats, safety glasses or goggles, and steel-toe boots will be worn. • Loose clothing that may catch in moving parts will not be worn. g:l obs19405491H&SplaMpfan 4 940549.00