By way of a grant through DEP’s Growing Greener program, the Indiana County Conservation District (ICCD) installed a lime-dosing silo to treat the Lucerne 3A discharge that negatively impacts the 6.5 mile stretch of Two Lick Creek. This project was completed in 2011 and with funding from other sources including DCNR, Indiana County and the Conservation District were able to turn the 10.7-acre site into a community park which features a walking trail, pavilion, fire pits, and interpretive signage for environmental education.
Underestimated at the time, the lime-dosing silo has proven to be a maintenance challenge. Due to the high corrosiveness of the discharge as well as the lime, the doser is constantly breaking and requires routine, weekly maintenance. Due to constant required maintenance needs, it’s more an active than passive system. Furthermore, funding is not readily available to purchase lime to fill the doser. After eight years, the Indiana County Conservation District has exhausted funds for purchasing lime. Even more so, the discharge is close to the stream which does not allow for enough time for the dosed lime to react with the discharge nor enough settling ponds to collect sludge before meeting Two Lick Creek.
As a result of all the previously mentioned issues, the ICCD submitted a request for engineering assistance from Stream Restoration Incorporated (SRI) to evaluate the effectiveness of the system and determine if another solution was feasible for treating the discharge. SRI determined that it would be feasible to treat the discharge using a series of passive treatment ponds.
Due to a lack in elevation change on the site, the discharge will go through a flow-splitting pool, then to two layered-style vertical flow ponds that would have a few feet of limestone with approximately 6″ to 1′ of compost on top as well as a water cap. The final pond would be an aerobic wetland before discharging to Two Lick Creek. During the design phase of the project, SRI will determine if it is possible to put in a TIF at the beginning of the system to promote low pH Iron removal. The conceptual design for this system is expected to improve the water quality of the discharge before it enters Two Lick Creek better than the current lime dosing silo.