The headwaters of Loyalsock Creek are a high-quality major sub-watershed to the West Branch Susquehanna River. The waters are impacted by two mine tunnel drainage discharges, which supply a significant level of acidity. Treatment systems designed and constructed in the 1990s resulted in some success in treating the discharge waters, but have been deteriorating in efficacy over time.
To correct the deteriorating infrastructure, Kleinfelder was selected to design two new passive treatment systems for the mine water discharges. The new treatment facilities will treat higher rates of discharge and will offer easier operations and maintenance for the plant operator.
Adequate design of a new treatment solution provided three significant challenges:
Kleinfelder’s proposed design includes an improved flow distribution box at the B-vein tunnel discharge. This improvement will capture and treat higher flows, allow for high flow bypass, and will create an easier method for handling possible sediment issues during high-flow events. This will provide treatment of flows up to 1,000 gallons per minute, with piping that will allow for an increase up to 2,000 gallons per minute.
At the C-vein discharge, Kleinfelder has proposed a new discharge catchment system to minimize sediment from entering the system. Conversion of the current pond to an upflow oxic limestone drain will allow for inflow up to 1,500 gallons per minute (an increase from 300 gallons per minute, currently).
Additional proposed features include a flush pond to be used as a storage mechanism for high-flow sediment. Treated waters will also be kept within limestone and pipes as much as possible to help mitigate thermal pollution.
The Loyalsock Creek Passive Treatment Plant is currently in the design phase, with plans to complete designs by early 2024 and begin construction by late 2024.
Treatment of large flows will decrease the aluminum concentration and, most notably, increase the pH and alkalinity concentrations in Loyalsock Creek, which will improve the mainstream fishery.
Sullivan County, PA
Pennsylvania Department of Environmental Protection