| dc.description.abstract | ABC’s Generating Station has low volume waste treatment ponds (LVWTP) that receive flow from plant
floor drains, bottom ash overflow, boiler blowdown and equipment leaks. Bottom ash overflow makes up
the majority of the influent to the LVWTP. The bottom ash overflow is also the primary source of solids
settlement in the ponds. Approximately 7,000 cubic yards of solids are deposited in the ponds each year.
The steep side slope of the pond berms, along with the inability to effectively dewater the settled solids
makes periodic sediment removal a very difficult and costly operation.
A consulting firm was hired to design and oversee construction of a sedimentation basin that would
remove the majority of sediment out of the waste stream before entering the treatment ponds. Two
concrete basins were constructed with 50’ x 20’ at the bottom with 50’ of ramp to access during cleaning.
The purpose of this paper is to summarize design and construction of the basins as well as testing that was
conducted to determine how well the sediment basins perform. The basin testing was conducted on April
20, 2012. The waste flow was sampled for TSS upstream of the sediment basins and downstream of the
basins in order to reach a percentage of TSS removed by the basins. Based on the April 20, 2012, testing,
the sedimentation basins reduced the amount of TSS in the waste stream by 53%. For the test taken on
April 20, the incoming TSS was 17.75 mg/L and the outgoing TSS was 9.5 mg/L. | |
