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F-4. AMENDMENT TO CONSTRUCTION MANAGER AT RISK CONTRACT FOR WHITE TANKS FLOOD RETARDING STRUCTURE #4 - PHASE 2 Amend the authorization under agenda item number C-69-12-049-5-00 for the Flood Control District of Maricopa County (District), which authorized the award of a Pre-Construction Contract and a Construction Services Contract (FCD 2011C022). This amendment will increase the not to exceed amount to $27,000,000. The previous authorized amount was $19,000,000. This action will allow the construction contract to be processed more expeditiously when signed. The Joint Venture of Sundt/Rummel was selected under a qualification-based selection in accordance with Maricopa County Procurement Code, Article 5, Paragraph 504(F) and Article IV of the Maricopa County Procedures Manual. White Tanks Flood Retarding Structure (FRS) No.4 is an earth embankment flood control dam designed and built by the Soil Conservation Service (now the Natural Resources Conservation Service, or NRCS) in 1954. The dam is located one half mile south of Interstate 10 on the west side of Jackrabbit Trail. The dam is operated and maintained by the District and is regulated by the Arizona Department of Water Resources (ADWR). The planning phase of the Project recommended overall rehabilitation of the dam. 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 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 Agenda Item impacts Supervisorial District 4. (C-69-12-049-5-01)

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F-2. AMENDMENT CONTRACT WITH SUNDT/RUMMEL FOR CONSTRUCTION MANAGER AT RISK FOR WHITE TANKS FLOOD RETARDING STRUCTURE #4 - PHASE 2 Authorize the execution of this amendment by the Chairman for the Construction Manager at Risk contract with Sundt/Rummel, A Joint Venture as the selected respondent to a Request for Qualifications for White Tanks Flood Retarding Structure (FRS) No.4 Phase 2 Construction Manager at Risk Pre-Construction and Construction Services. Authorize the Chairman to execute any and all additional contracts to The Joint Venture of Sundt/Rummel necessary to complete the construction without further action by the Board of Directors provided that the aggregate of all such contracts does not exceed the sum of $27,000,000. White Tanks Flood Retarding Structure (FRS) No.4 is an earth embankment flood control dam designed and built by the Soil Conservation Service (now the Natural Resources Conservation Service, or NRCS) in 1954. The dam is located one half mile south of Interstate 10 on the west side of Jackrabbit Trail. The dam is operated and maintained by the District and is regulated by the Arizona Department of Water Resources (ADWR). The planning phase of the Project recommended overall rehabilitation of the dam. Phase 1 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 2 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 Agenda Item impacts Supervisorial District 4. (C-69-12-049-5-02)