Sequoia was awarded the contract to construct a 27 acre containment for potentially acid generating mine spoils for a confidential client in the Southeastern United States. The containment cell construction required close coordination with the Owner’s mining operations to ensure the containment capacity was prepared in time to support mining operations. In addition, the Owner coordinated the installation of geomembrane liner and permitting and initial filling of a wetland area that impacted about half of the work area.
Sequoia began the project by filling areas of the cell to subgrade while the Owner placed rock in the wetland area. Sequoia imported 430,000 cubic yards of material from several onsite sources that was used as structural fill, clay liner and protective cover materials. Once the 1.2 million square feet of low permeable soil liner was constructed, the Owner coordinated the placement of geomembrane liner so that Sequoia could continue to install 9,200 linear feet of underdrain piping and complete the placement of a 2 foot protective cover layer over the geomembrane. The total project was completed in 7 months.
