Project:
Foothill and North County Landfill Expansions
Overview
Foothill Sanitary Landfill, located along the eastern border of San Joaquin County, is the largest landfill site in the County, around 800 acres in size. It has an average daily volume of 952 tons. North County Landfill encompasses 320 acres and receives an average of 541 tons of waste daily with a permitted quantity of 1,200 tons.
Location:
San Joaquin County
Owner / Client:
San Joaquin County Department of Public Works
Performance Period:
2015-2023
Services:
- Solid Waste Engineering
- Construction Quality Assurance (CQA)
Scope of Services Provided by AES
Since 2015, AES provided CQA services for five landfill expansion projects including 3 expansions totaling 38 acres for Noth County and 2 cell expansions totaling 35 acres for Foothill Landfill in San Joaquin County, CA. The 5 projects included total of over 10 million sq. ft. of geosynthetics materials including HDPE geomembrane, GCL, geocomposite, and geotextile.
Module 2A and 2B Liner at Foothill Sanitary Landfill – Module 2A involved 15-acre expansion including floor and side slope composite liner. The scope included approximately 200,000 cu. yds. of earthwork; testing of 1-foot-thick foundation layer on floor; monitoring and testing of 2.1 million sq. ft. of geosynthetics; monitoring of leachate collection and removal system (LCRS) construction; protective soil cover installation; gas collection pipe and lysimeter installation; perimeter berm construction; testing of subgrade for access road construction; and miscellaneous drainage improvements. Module 2B included a 24-acre cell expansion and 30,000 cu. yds. of low-permeability subgrade layer and 2.7 million sq. ft. of geosynthetics.
Area 5A and Area 5B, and Area 6 Liner at North County Sanitary Landfill – The 3 projects involved 38 acres of liner expansion involving floor and side slope liner. The scope included approximately 300,000 cu. yds. of earthwork; testing of 1-foot-thick foundation layer on floor and 6-inch-thick subgrade preparation layer on side slope; monitoring and testing of 4.7 million sq. ft. of geosynthetics; monitoring of LCRS construction; protective soil cover installation; gas collection pipe and lysimeter installation; perimeter berms; access road construction, and miscellaneous drainage improvements.
Our services included review of cell design and Plans and Specifications for constructability; review of quality control data for geosynthetics and earthwork materials; conformance testing of geosynthetics materials and interface shear strength tests; CQA services for earthwork, geosynthetics and LCRS; leak location surveys; and preparation of as-built CQA reports.
Accomplishments / Commendations
Our high-quality responsive services and our value engineering design modifications were recognized by the client:
“I had the pleasure of working with Kris Khilnani and Michael Raub on several landfill expansion projects over the past five years, during which AES provided CQA services for four composite liner projects for the County. I was very impressed with the breadth of their technical knowledge, sensible recommendations, quick turn-around on projects, and their professionalism. Their deliverables were thorough and well written and they met regulatory agency approvals with minimal or no comments. AES’s constructability review of the plans and specifications for the landfill projects uncovered discrepancies which spared the County from potential liabilities, resulted in cost savings, and allowed for construction with no complications. Kris, Michael and the entire team at AES are highly skilled and competent engineers, with great work ethics and intense dedication to our demanding industry.”