Moretrench’s services also include earth retention, deep foundations, ground freezing, and industrial construction. This wide range of in-house expertise allows the company to offer turnkey solutions to address multiple geotechnical challenges at an individual storage facility, often under a single contract.
Ash Pond Cut-Off & Containment Barriers Archives - Moretrench
Perimeter or down-gradient cut-off or containment to prevent migration of contaminated groundwater and facilitate ash pond closure can be accomplished by a range of specialty geotechnical methods. Selection of the most appropriate option is dependent on the subsurface conditions, site-specific project requirements, and cost considerations.
Grouted groundwater cut-offs can be constructed by the installation of overlapping jet grout columns to an impermeable stratum or by the vibrated beam method. Vibrated beam cut-offs are installed by the repeated driving of a wide-flanged steel beam using a vibratory hammer, while simultaneously injecting cement-bentonite slurry through nozzles attached to the underside of the beam to form a thin curtain wall.
Soil-bentonite slurry trenches are constructed by excavating and keying into a suitable cut-off stratum under a viscous slurry to maintain sidewall stability. The excavated material is mixed with bentonite and returned to the trench, displacing the slurry and completing the cut-off. When additional strength is required, cement grout may be added to the backfill.