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Apr . 4. 2000 5 : 04AM No - 1112 P . 6/17 Preliminary Endangerment A.ssemnent Work Plan Proposed Joe Widmer Elementary School January 11,2000(Revised Much 24,2000) Page-3- prepared by Radian and dated November 16, 1998,TCE was last detected in monitoring well 506A in the third quarter of 1991 and all four of the wells were abandoned on April 30, 1998. The wells were abandoned by pressure grouting at 250 pounds per square inch. Data associated with former monitoring wells 506A, 506B, 506C, and 506D are included in Appendix C. 3. FIELD AND ANALYTICAL METHODS This section includes a description of proposed site health and safety procedures, proposed soil sampling procedures, and laboratory analyses_ 3.1 HEALTH AND SAFETY REQUIREMENTS Prior to initiating fieldwork at the site, all field personnel will familiarize themselves with the site- specific Health and Safety Plan included in Appendix D. The Health and Safety flan pertains to field activities and includes information such as potential hazards encountered at the site, personal protective equipment, and directions and.telephone numbers to the nearest hospital. All personnel working at the site will have completed 40 hours of classroom training and 24 hours of supervised field training concerning hazards that may be encountered at hazardous waste sites. Additionally, all field personnel working at the site will participate in a medical monitoring programa. 3.2 FIELD SAMPLING PLAN The field sampling plan described in this section is based on information contained in the DTSC Preliminary Endangerment Assessment Guidance Manual and Draft Version 1.4 of Guidance for Sampling Agricultural Soil,}' previously mentioned in Section 1. Verbal information provided by DTSC personnel was also used to develop the field sampling plan. The DTSC has informed Condor that groundwater sampling is not required. 3.2.1. Soil Sampling Plan Because fill soil has recently been placed at the site, soil samples will be collected from the fill at a depth of 0 to 6 inches and from the soil below the fall at a depth of approximately 3 to 3.5 feet below the existing ground surface. At the request of the DTSC, 15 four-to-one composite surface soil samples will be collected from the fill, and ten four-to-one composite samples will be collected from approximately 3 to 3.5 feet below existing grade for laboratory analyses for pesticides and herbicides. Four discrete soil samples will also be collected for laboratory analyses for arsenic, lead, and selenium. Two of these samples will be collected from the fill and the remaining two discrete soil samples will be collected from the soil below the fill at a depth of approximately 3 to 3.5 feet below the existing ground surface. Additionally, two discrete deep soil samples will be collected from approximately 3 to 6 feet below the previous grade (approximately 6 to 9 feet below current grade) for laboratory analyses for pesticides, herbicides, arsenic, lead, and selenium. At the request of the DTSC, two discrete soil samples will be collected off-site on adjacent property for the purpose of obtaining background data pertaining to arsenic, lead, and selenium. The locations of the two background samples will be determined in the field. The proposed composite soil sample locations and the proposed discrete soil sample locations are shown in Figure 3, Appendix A. Each composite sample will consist of four subsamples collected at least ten feet apart. The subsamples obtained frons the fill will be collected at the surface (0 to 6 inches) by loosening the soil with a stainless steel shovel. A stainless steel spoon will be used to place the loose soil