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Libbey Owens Ford Co. Pmiuct Recovery System Installation June 23, 1997 Page-3. 3.1 Product Recovery Trench Prior to fieldwork, underground utilities within the work area will be delineated by LOF personnel. The PHS/EHD will be notified of the installation schedule at least 48 hours in advance. Prior to commencement of the installation. a tailgate safety meeting will be held and a site-specific Health and Safety Plan will be discussed with, and presented to, all crew members for their signatures. A copy of the Health and Safety Plan is contained in Appendix C of this document. Preliminary work will include the removal of a portion of existing underground diesel delivery line (Figure 4, Appendix A). Prior to removal, the pipe line will be inspected to insure that no diesel product remains in the line. The remaining ends of the line will be capped and secured properly. In addition, the concrete roadway (approximately 1 foot thick) will be cut where the proposed trenches cross the roadway. The trenching will be performed by a qualified contractor, under the supervision of a Condor geologist or engineer. The fieldwork will include excavation of approximately 350 linear feet of 12- inch wide.trench to a depth of approximately 15 feet bas. Groundwater is anticipated to be encountered at approximately 1 I feet bgs. The trenches will be excavated to a depth of approximately 15 feet bgs in 20 to 40 foot linear segments separated by small earth dams in the bottom of the trench. Since the aquifer is known to have a low yield, and groundwater is expected to seep into the trenches at a slow rate. The trench segments will be continually inspected during excavation. If product does not begin accumulating in the trench, excavation work may be suspended or terminated. LOF will provide a vacuum truck during excavation work to remove available product. Excavation of the earth dams will be performed after the product recovery wells are installed and prior to backfilling the trenches with gravel. It is possible that the most efficient recovery configuration will incorporate use of the earth dams. Field observations will be used to decide if any of the earth dams should remain. In no case will any segment of the trench not be connected to a product recovery well During the trenching, contaminated soil will be segregated from non-contaminated soil. The soil will be screened by use of a photoionization detector (PID), by physical observation. and by C� CONDOR