Construction of the SR89 passive treatment system was completed last September 2019 making it the newest system in the Slippery Rock Creek Watershed in Butler County.

The SR89 system, which is located on State Game Lands #95, was constructed by Seneca Landfill, Inc., to offset and mitigate stream impacts associated with their mine permit and landfill extension project.

The system utilizes a Terraced Iron Formation (TIF) also known as an Oxidation Precipitation Channel (OPC) to collect various acid mine drainage seeps and promote iron removal at low pH utilizing biogeochemical processes.

The acid mine drainage flows through a Jennings-style Vertical Flow Pond containing a mixture of limestone aggregate, mushroom compost, and woodchips.

The water then flows into a settling basin and wetland to promote iron oxidation and settling of metal solids before discharging to Slippery Rock Creek.

Slippery Rock Watershed Coalition participant Cliff Denholm collected water samples at the site in June of this year as part of the Statewide Snapshot. This was the first time that the system has been sampled.  [Click Here for detailed sample results.]

Overall, the treatment system was performing well. The acidic water went from a very low 3.3 pH with no alkalinity, to being net-alkaline with a good 6.7 pH.

More than 80 percent of the iron and almost all of the aluminum is being captured in the system. Iron removal will likely improve once the wetland plants, which act like a filter, become established.

This system has been a long time coming and the Slippery Rock Watershed Coalition is excited to see the effect this system, along with the planned rebuild and expansion of Ferris and SR81, will have on the downstream section of Slippery Rock Creek.

Click Here for more information about this treatment system on the Datashed website.

[Through public-private partnership efforts the Slippery Rock Watershed Coalition has installed over 20 passive treatment systems, successfully treating over 1.5 billion gallons of mine drainage each year.]

[How Clean Is Your Stream?

[DEP’s Interactive Report Viewer allows you to zoom in on your own stream or watershed to find out how clean your stream is or if it has impaired water quality using the latest information in the draft 2020 Water Quality Report.]

(Reprinted from the July Catalyst newsletter from the Butler County-based Slippery Rock Watershed Coalition.  Click Here to sign up for your own copy.)

Related Articles:

-- Statewide Water Sampling Underway At 300 Passive Mine Drainage Treatment Systems In PA

-- Bay Journal: Fix For PA's Sewage Overflow Pollution - Worst In U.S. - Neither Quick Nor Easy

[Posted: July 20, 2020]

7/27/2020