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13. INSTALLATION OF LEACHATE CONTROL MEASURES In December, 1990, San Joaquin County hired Kleinfelder Inc. to perform a Leachate Generation Study for the Harney Lane Sanitary Landfill. Kleinfelder used the Hydrologic Evaluation of Landfill Performance (HELP) and the Seasonal Soil Compartment (SESOIL) computer models for the study. The groundwater under the Harney Lane Sanitary Landfill is approximately 100 feet below the bottom of the landfill. The results of Kleinfelder's study showed that leachate transit time to the ground water table is a minimum of 25 years, assuming a near saturated initial waste moisture content of . 29 vol/vol. (Previous studies performed by Kleinfelder indicated that waste moisture content is very seldom near the saturation point) . The study also predicted that average annual leachate generation over a 20 year period can vary from . 0025 inches to 3 . 1588 inches. Because of the extensive transit time (25 years minimum) of leachate, the low annual leachate production (3 . 1588 inches maximum) , and the absence of a liner at the site, a leachate monitoring system and/or control system is infeasible and unnecessary. Article 7.8, section 17781 (e) (1) states "The operator shall collect leachate in accordance with Title 23 , CCR, Subchapter 15, Section 2543 , and approved by the local enforcement agency and the board" . Section 2543 of Subchapter 15 states "Leachate collection and removal systems are required for Class I landfills, surface impoundments, and waste piles; for Class II landfills and surface impoundments; and for Class III landfills which have a liner or accept sewage or water treatment sludge" . The Harney Lane Landfill does not have a liner and does not accept sewage or water treatment sludge; therefore, a leachate collection and removal system is not required and is not proposed in the Final Closure Plan. 14. INSTALLATION OF GROUNDWATER MONITORING NETWORK The groundwater monitoring network is in place and consists of one upgradient monitoring well (MW-1) and three downgradient monitoring wells (MW-2 , MW-3 , MW-4) (See sheet 3) . The wells were installed in March, 1987 by EMCON Associates. The borings for MW-1, MW-2, MW-3 , MW-4 were drilled with air-rotary drilling equipment to depths of 159 , 147 , 148, and 144 feet, respectively. Samples were taken every 5 feet by an EMCON geologist. Boring logs and well construction details are included in the Ground-Water Monitoring Plan Implementation; Harney Lane Sanitary Landfill, San Joaquin County, California (Appendix E) . The monitoring wells are constructed of 4 . 5 inch polyvinyl chloride casing with 50 foot screened intervals. The completed wells were developed by bailing, 13