ARCHIVED REPORTS_JULY 2014 FINAL RCSI

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WASTE DISCHARGE REQUIREMENTS ORDER NO. R5-2014-0006 -23- FORWARD INC. AND REPUBLIC SERVICES INC. FORWARD CLASS II LANDFILL SAN JOAQUIN COUNTY suction gradient over most of the year; and a net negative moisture flow (upward movement of moisture and long-term drying of the underlying waste) over the four-year test period. 97. Title 27 section 21090 requires that final cover systems contain a low-hydraulic conductivity layer that exhibits a saturated hydraulic conductivity of less than 1 X 10-6 cm/sec, or equal to the hydraulic conductivity of the bottom liner system or underlying natural geologic materials, whichever is less. The alternative final cover demonstration project showed that in this location and using site soils the water balance/evapotranspiration engineered alternative cover meets or exceeds the performance goals of Title 27. 98. Side slopes for the closed landfill will be sloped at 3H:1V and will include 15-foot wide benches every 50 vertical feet or less as required by Title 27. 99. The Discharger performed a slope stability analysis for the proposed final cover. The Discharger’s static and dynamic stability analysis demonstrates that the side slopes of the final cover will be stable in accordance with the requirements of Title 27. 100. Pursuant to Title 27, section 21090(e)(1), this Order requires a survey of the final cover following closure activities for later comparison with iso-settlement surveys required to be conducted every five years. 101. This Order approves the proposed final cover and requires that a final closure and post- closure maintenance plan, design documents, and CQA plan be submitted for review and approval at least 180 days prior to actual closure. LANDFILL POST-CLOSURE MAINTENANCE 102. The Discharger submitted a December 2008 Preliminary Closure and Postclosure Maintenance Plan (Appendix L of the Report of the Joint Technical Document) for closure and post-closure maintenance of the landfill. The plan includes inspection, maintenance, and monitoring of the landfill during the post-closure maintenance period, and a post-closure maintenance cost estimate for the entire facility. Inspection and maintenance will include the condition of the final cover, drainage features, LCRS, groundwater monitoring wells, unsaturated zone monitoring points, landfill gas system, groundwater corrective action system, and site security. The plan will be implemented for a minimum period of 30 years or until the waste no longer poses a threat to environmental quality, whichever is greater. 103. Once every five years during the post-closure maintenance period, aerial photographic maps of the closed landfill area will be made to identify and evaluate landfill settlement. Iso- settlement maps will be prepared to determine the amount of differential settlement occurring over the previous five years. Pursuant to Title 27, section 21090(e)(2), this Order requires iso-settlement maps to be prepared and submitted every five years. 104. The completed final cover will be periodically tested for damage or defects by monitoring surface emissions pursuant to California Code of Regulations, title 17, section 95471(c) and