The Big Bear Sanitary Landfill is an inactive Class III Landfill located in an unincorporated area of San Bernardino County, approximately 2.5 miles north of the town of Big Bear City. The site encompasses 79 acres, of which approximately 32 acres were used for refuse disposal. An 8-acre “lower level” disposal area was closed in 1989. Closure of the 24-acre “upper level” was completed in 2010.
AES provided CM services for final closure involving 5-foot-thick monolithic/evapotranspirative (ET) soil cover on slopes and geomembrane/soil cover on top deck, benches, and access road. The monolithic soil cover included a 1-foot-thick existing interim cover and an additional 4-foot-thick layer consisting of onsite stockpiled material with approximate volume of 170,000 cu. yds. The other fill materials included subgrade fill, foundation layer, and protective soil cover over geomembrane.
Final cover for top deck and benches consisted of composite soil/geosynthetic cover including a 60-mil linear-low density polyethylene (LLDPE) geomembrane over a minimum 1 foot of existing interim soil and 1 foot of foundation soil layer. The geomembrane was covered by drainage geocomposite, edge drains, and 2 feet of protective cover soil. Closure construction required placement of final cover up to the property lines and included segmental concrete block walls, reinforced earth slopes, and concrete retaining walls were constructed for steepened slope areas.
CM services also included contract administration, cost and schedule control, material quantity estimates, processing progress payments, contractor submittals, response to RFIs and Change Orders, reviewing and approving submittals, conducting weekly meetings, and coordination with multiple agencies and A-E firms. AES set up a state-of-the-art MIS for this purpose.
CQA services included drainage structures, AC paving, fencing, interim LFG header and horizontal collector and LFG migration monitoring probes.
AES prepared an As-Built CM and CQA Report including verifying as-built drawings prepared by the Contractor and coordinating with Design A-E firm. At the completion of the project, AES prepared a CM report enclosing all contract administration documentation, as-built drawings, and CQA for miscellaneous improvements including AC, concrete, and LFG improvements.