A speck of dust to bring life back to Hewett Fork Creek

September 7, 2022

As more and more coal mines continue to shut down in the once-booming region of Southeastern Ohio, local communities are experiencing many social and economic impacts. However, the most overlooked impact of all could be the environmental one.

After the coal boom in the late 1800s and early 1900s, underground water began filtering between the rocks and flooding the abandoned mines. The remaining coal, rich in pyrite, in combination with oxygen and water, created Acid Mining Drainage (AMD). When AMD emerges to the surface, it turns the surrounding area into an inhospitable ecosystem.

An example of this phenomenon is the Carbondale Mine AMD that has been released into Hewett Fork Creek, a tributary of the Raccoon Creek that converges with the Ohio River downstream. The Carbondale Doser, located in Waterloo township in Athens County, is an example of an AMD treatment facility managed by Raccoon Creek Partnership and the Ohio Department of Natural Resources (ODNR), among others. Constructed in 2003, the doser was meant to replace the wetlands used previously to treat the area. The objective of both the wetlands and later the doser was to reduce the AMD impact on Raccoon Creek, and by doing so, also to improve the quality of water and habitat for local species.

Amy Mackey holds a precipitated iron plastered created from Acid Mining Drainage (AMD) in the Carbondale Mine, Waterloo township in Athens County, Ohio.

 The first attempt to improve the quality of water was made by the ODNR in 1991. ODNR provided treatment for alleviating the load of AMD coming out of the mine by installing 10 ponds lined with clay and then layered with limestone and organic substrate. The wetlands provided a low-cost, low-maintenance, and effective means of achieving the long-term treatment of AMD, while also working as a reservoir of other precipitate materials. Unfortunately, this treatment system did not meet the acidity reduction target. A water-wheel dosing unit was installed as a replacement for the wetlands. Originally, it was intended to use limestone powder; however, as lime becomes easily armored, it can no longer neutralize AMD. Therefore, it was replaced with calcium oxide, which resulted in a more efficient, though expensive, neutralizing agent. 

The Ohio Watershed Data reported in 2011 an approximately 758 lbs/day of AMD had been prevented from entering Hewett Fork. Another 186 lbs/day of extra alkaline material went to the Creek that continued to neutralize the pH in the water downstream. The acidity levels 11 miles downstream before the construction could reach a pH of 2.8 to 5.9. Now, the pH ranges between 6.2 and 9.3. As a result of neutralizing the water, seven species of fish can now be encountered where a few years ago none were found. 

According to Amy Mackey, Raccoon Creek Watershed Coordinator and Research Associate for the Voinovich School of Leadership and Public Service, even though the results are positive, the doser requires constant maintenance. The original investment for the construction of the facility was $440,000, but a yearly additional budget of $40.000 is needed to fill it with calcium oxide. There are also other expenses such as education programs and the labor to maintain the facilities.

Considering the potential damage that would ensue if this doser shut down, it may be of interest to understand where funding for these ongoing expenses comes from. As most of the mines that produced AMD problems were closed before any regulations were created, a tax on coal mining nowadays is directed toward funding restoration projects like this. So, one question remains: what will happen when there is no more coal to extract and tax?