Wick points provide cost-effective ash drainage and consist of a geotextile filter fabric wrapped around a molded plastic core. The fabric is specially designed to allow water drainage while retaining fine-grained fly ash particles. Wick points are well suited when flow rates are low, longevity is not a concern, and rapid installation is required.
Ash Pond Dewatering Archives - Moretrench
Deep wells are equipped with individual submersible pumps and can be installed to much greater depths than wellpoints. A deep well system can pump up to thousands of gallons per minute and is best suited to material of high hydraulic conductivity and where permeable soils extend well below the bottom of the pond or impoundment.
The basic wellpoint system consists of the wellpoints themselves, header piping, and a centrally located pumping system. Depending on the area to be dewatered, the system can comprise just a few wellpoint devises and a single pumping station, or many thousands of wellpoints and multiple pumps. Wellpoints are very effective in fly ash of low hydraulic conductivity and when close spacing is required.
Lowering the water content of ash pond materials by pre-drainage dewatering effectively increases its cohesion and shear strength, allowing stable, near-vertical cuts to be made for mass removal with conventional, even tire-mounted, excavators. The primary methods of ash dewatering are wellpoints, deep wells and wick points.