Olinda-Alpha and Santiago Canyon Landfills – CM/CQA Services for Final Closures

Scope of Services Provided by AES

AES provided CQA services for the Phase 1 and Phase 2 final closure involving construction of 5-foot-thick monocover for the 64-acre Phase 1 closure and 88-acre Phase 2 closure. Cover construction included placement of 520,000 cu. yds. of material for Phase 1 and 700,000 cu. yds. for Phase 2. Other construction activities involved cover thickness characterization, landfill gas system improvements, retaining walls, 125,000 sq. ft. of geomembrane lining, surface water drainage structures, and access road improvements.

Our scope included constructability review of the alternative cover design, and plans, specifications, and CQA Plan; stockpile characterization and construction of a test pad to help develop a procedure for oversize control and cover placement and compaction procedures; CQA services including cover construction, refuse removal and reconsolidation, placement of LLDPE geomembrane infiltration barrier along with geocomposite drainage layer and drainage collector, construction of LFG improvements, inspection and testing of concrete, asphaltic concrete, CLSM and grouted riprap for drainage improvements, retaining walls, tank foundations and roads, and construction of site utility improvements including water and gray water lines, sewer lines, electric lines, steel storage tanks, and pumping stations; and preparation of As-Built CQA Report for submittal to regulatory agencies.

Santiago Canyon Landfill – The County operated the site as a municipal solid waste landfill from 1968 to 1993 with reduced operations for three additional years. The County ceased accepting waste at the site in mid-1996. Its current Land Use designation is Natural Community Conservation Plan mitigation site and open space.

AES provided CM services for final closure involving construction of 5-foot-thick monocover for 100 acres of side slopes and 30 acres of top deck, including placement of 900,000 cu. yds. of material. Other construction activities involved surface water, access road, LFG improvements, and installation of multiple gas probes around the landfill perimeter. Our scope of services included CM services including contract administration, cost and schedule control; earthworks and monocover thickness control; Digital Terrain Model to optimize cover utilization; CQA services for LFG improvements, concrete, AC, grouted riprap, and soil cement for drainage improvements and roads, foundation and structural inspection for new office building, and installation of multi-depth LFG perimeter probes; and preparation of As-Built CQA Report for submittal to regulatory agencies.