Mining & Metals
Aggregate Miner Slurry Program - Southwest
- Installation of new cutoff barriers to facilitate dry mining operation
- Replace existing cutoff barriers exceeding seepage requirement for sealed water storage reservoir
- Serve as surface water storage reservoir upon decommissioning
- Construction of a 9,080 LF, 65 FT deep (363,200 SF) soil-bentonite slurry wall
- Construction of a 7,438 LF, 30-FT deep (218,677 SF) soil-bentonite slurry wall
ENTACT is a dedicated slurry cutoff wall contractor for this major aggregate miner/supplier. ENTACT was initially contracted by the owner to replace an existing defective cutoff wall that exceeded the State Engineer’s Office (SEO) and Division of Minerals and Geology’s (DMG) allowable seepage requirement for a sealed water storage reservoir. Scope of work included construction of a 9,080 foot long, 65 foot deep, 30-inch wide (363,200 facial square foot) soil-bentonite slurry wall which was keyed a minimum of 4.0 feet to 5.0 feet into the underlying competent bedrock. Following the successful completion of the first project, ENTACT was subsequently awarded additional work that included the construction of a 7,438 foot long, 30-inch wide soil-bentonite slurry wall with an average depth of 29.4 feet and a total facial area of 218,677 square feet. The cutoff walls were required in order to minimize dewatering efforts and facilitate dry mining operations while ultimately allowing the mined pits to serve as a surface water storage reservoir upon decommissioning.
ENTACT’s responsibilities also included location and protection (through concrete encasement) of many subsurface utility lines that penetrated the proposed slurry wall alignments, as well as coordinating daily construction operations with active mining operations.