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Foothill Sanitary Landfill — Module 1 December 2003 <br />County of San Joaquin Job No 031602 00 02 <br />5.3.3.2 Repair Procedures and Testinc <br />All repairs were conducted in accordance with the applicable method specified within <br />the Technical Specifications. Each repair was logged by Vector's CQA Monitor and <br />subsequent testing was performed. Repairs and testing is documented in the repair log <br />presented in Appendix J. <br />5.3.4 Investigation of Water Under HDPE Geomembrane <br />During inspection of the liner system that remained uncovered near the completion of <br />the project, Vector's CQA Monitor observed that water was entrapped between the <br />geomembrane and the GCL. The water under the geomembrane was located at the <br />northeast area of the module's floor where the lateral and header LCRS pipes intersect <br />in the V -ditch, (see Figure 6). <br />At the County's request, the Contactor opened the geomembrane liner at the pipe <br />junction and removed approximately 40 -gallons of water from the surface of the <br />underlying GCL. The liner was opened further to expose all affected areas in the V - <br />ditches at this pipe intersection until competent GCL was found. The damaged GCL <br />was removed and replaced, and the liner system was repaired and approved by <br />Vector's CQA Monitor in accordance with the applicable methods described in the <br />technical specifications. <br />5.3.5 Leak Location Survey <br />Leak Location Services, Inc. (LLSI) of San Antonio, Texas, conducted two leak surveys <br />using an electronic leak detection method. In summary, an electronic leak survey is <br />performed by electrifying the operations layer to approximately 300 volts, while the soil <br />beneath the GCL is "grounded". LLSI technicians apply electrical probes at regular <br />intervals to detect the current through breaches in the geomembrane (See Appendix K). <br />In LLSI's survey, the module's floor and sideslopes were tested. No leaks were <br />detected by the survey. A complete report of the procedures and findings of the leak <br />location survey are included in Appendix K. <br />Vector Engineering, Inc. - 143E Spring Hill Drive - Grass Valley, CA 95945 - (530) 272-2448 <br />33 <br />