Compacted Clay Liner Test Pad Construction and Testing ASARCO
HWA GeoSciences Inc. provided on-site and laboratory testing services during the design, construction and testing of a compacted clay liner (CCL) to be utilized during the construction of a hazardous waste landfill at ASARCO’s Superfund site in Ruston, Washington. Prior to finalization of the soil/bentonite mix for use on the test pad, three trial mixes were evaluated. The intent was to develop an economical mix of on-site glacial borrow soil and sodium bentonite, that when compacted would consistently exhibit an in-place hydraulic conductivity of 1.0 x 10-7 cm/sec or less. During the trials, three different mixes were evaluated and constructed into test strips that were sampled and tested. Once the design mix was determined, a demonstration test pad was constructed that would accommodate a sealed double ring infiltrometer (SDRI). Each lift of the pad was sampled and tested for index properties such as grain size, Atterberg limits, unit weight, and vertical permeability. Following the construction of the test pad, a large scale SDRI apparatus was installed and infiltration testing was conducted for a period of about four months. After the infiltration testing was completed, the test pad was excavated, sampled and tested. Final testing consisted of a vertical moisture content profile, vertical permeability, and soil suction estimates at various depths within the pad.
Other Notable Projects:
Tacoma Landfill Improvements City of Tacoma
Everett Landfill Closure and Brownfields Feasibility Study City of Everett
Cedar Hills Landfill Area 6 Development King County Department of Natural Resources
Ryegrass Balefill Landfill GasMonitoring Kittitas County Public Works Department
Tulalip Landfill Superfund Site Waste Management Inc.
Bow Lake Transfer Station Improvements King County Department of Natural Resources
HWA GeoSciences Inc. provided on-site and laboratory testing services during the design, construction and testing of a compacted clay liner (CCL) to be utilized during the construction of a hazardous waste landfill at ASARCO’s Superfund site in Ruston, Washington. Prior to finalization of the soil/bentonite mix for use on the test pad, three trial mixes were evaluated. The intent was to develop an economical mix of on-site glacial borrow soil and sodium bentonite, that when compacted would consistently exhibit an in-place hydraulic conductivity of 1.0 x 10-7 cm/sec or less. During the trials, three different mixes were evaluated and constructed into test strips that were sampled and tested. Once the design mix was determined, a demonstration test pad was constructed that would accommodate a sealed double ring infiltrometer (SDRI). Each lift of the pad was sampled and tested for index properties such as grain size, Atterberg limits, unit weight, and vertical permeability. Following the construction of the test pad, a large scale SDRI apparatus was installed and infiltration testing was conducted for a period of about four months. After the infiltration testing was completed, the test pad was excavated, sampled and tested. Final testing consisted of a vertical moisture content profile, vertical permeability, and soil suction estimates at various depths within the pad.