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F-2. OPERATION AND MAINTENANCE AGREEMENT AND PLAN WITH U.S. DEPARTMENT OF AGRICULTURE NATURAL RESOURCES CONSERVATION SERVICES FOR WHITE TANKS FRS NO. 4 REHABILITATION PROJECT Approve the Operation and Maintenance (O&M) Agreement (Agreement) and O&M Plan (Plan) FCD 2015A015, between the U.S. Department of Agriculture Natural Resources Conservation Service (NRCS) and the Flood Control District of Maricopa County (District) for the White Tanks FRS No. 4 Rehabilitation Project (Project [#201.02.31]). The NRCS and Sponsor agree to carry out the terms of the O&M Agreement and O&M Plan, which defines the responsibilities for operating, inspecting, and maintaining rehabilitation work completed for the White Tanks FRS No. 4 Rehabilitation Project and existing structure features. The Agreement and Plan shall become effective when signed by both parties. The Agreement and Plan are required by the NRCS funding authorization process and for reimbursements of construction costs, prior to the construction of dam rehabilitation projects. Phase I of the overall rehabilitation is completed and consisted of the removal of the existing central filter material and replacement with a suitably engineered filter material. The central filter is an element of the dam that is designed to prevent a failure of the dam due to embankment cracking. Phase II construction which will start in January 2016 will remove the two existing corrugated metal pipe outlets and replace them with a single concrete outlet pipe system. The left auxiliary spillway will also be removed by extending the left abutment of the dam to the north. The right auxiliary spillway will be widened to accommodate the removal of the left spillway and the flood pool will be graded to remove the existing pit and dead storage. In addition the embankment will be raised to accommodate future land subsidence and regulatory requirements for freeboard and modified as needed to address all remaining dam safety issues. This item impacts Supervisorial District 4. (C-69-16-022-3-00)