Mine Tailings Cap – Castella, CA

PROBLEM: A Montana based mining company wanted to close down a mine and contain the tailings pile that had been created. The site needed to be blended in with the surrounding hills, and the tailings protected from leaching any residue into

the adjacent streams.

SOLUTION: The tailings were shaped so that the resultant profile blended into the local terrain. The entire mound was capped with a textured double sided HDPE geomembrane, covered with 4 foot of local soil, and then planted with local vegetation.

CONSTRUCTION DETAILS: A local general contractor brought in his heavy dirt moving equipment, and formed the tailings into the correct hill shape. Local soil cover was placed over the tailings. Northwest Linings and Geotextile Products crew arrived on site and deployed the HDPE material. All field seams were air pressure tested, and tensile tested as a quality control measures. 48 inches of free draining local soils were placed over the cap material. The entire area was seeded with a local grass mixture.

PROJECT: Altoona Mine Repository & Cover

LOCATION: Castella, CA ENGINEER: URS CONTRACTOR: EQM

LINER INSTALLER: Northwest Linings & Geotextile Products, Inc.

MATERIAL: 60 Mil textured Two Sides HDPE

AREA: 150,000 SF