Construct Repository Cover to Support the Callahan Mine Superfund Site in Brooksville, Maine.

Construct Repository Cover to Support the Callahan Mine Superfund Site in Brooksville, Maine.The general scope of work for the proposed contract involves installing a composite cap over an area of approximately 13 acres. The purpose of the cap is to limit infiltration through mine waste remaining after historical copper mine operations performed on the property. The mine waste consists of rock and rock-amended sediment previously consolidated and graded as part of recent and ongoing Superfund remediation activities. The expected components of the composite cap include in order from the surface: 12 inches crushed stone (3-inch minus), geocomposite drainage layer, 60-mil textured geomembrane (seam welded), and geofabric. Other activities to be performed under this contract may include installation of drainage features (e.g., swales, culverts, etc.), grading, seeding and stabilization of disturbed areas outside stone cover system, stockpile management, and wetland improvements.