Slippery Rock Creek Watershed Coalition: Repairs Made To McIntire Passive Mine Drainage Treatment System During Pandemic

We are thankful to the partners of the Slippery Rock Creek Watershed Coalition who helped make necessary repairs at the McIntire Passive Treatment System in Butler County during Pennsylvania’s state lockdown due to COVID-19.

The McIntyre Passive Treatment System, located in the Blacks Creek subwatershed, has been consistently treating water since 2011. 

An innovative passive system treats a highly acidic mine discharge with high concentrations of iron, aluminum, and manganese, which is one of the worst water quality discharges in the Slippery Rock Creek Watershed. 

The system utilizes Terraced Iron Formations (TIF) for low pH iron oxidation, a mixed media Jennings Vertical Flow Pond, a self-flushing automatic syphon as well as a solar powered SmartDrain limestone only Vertical Flow Pond, and two Horizontal Flow Limestone Beds. 

Prior to installation of the treatment system, the water had been left untreated since the 1990's when the H&D (Adobe) mining company forfeited their bonds. 

A land reclamation project was also completed in 2006 by Quality Aggregates Inc. who, under a contract with the PA DEP Bureau of Abandoned Mine Reclamation, applied about 9" layer of Mercer waste lime to specific "hot spots" identified with a conductivity study.

The passive treatment system has been successfully treating the discharge with little maintenance over the years. In May 2020, minor maintenance was conducted by Ryan and Cory Mahony of BioMost, Inc. including:

-- Stabilizing the outlet of a beaver pond

-- Adding a riser pipe for flow measurements within the Horizontal Flow Limestone Bed

-- Clearing vegetation from the Jennings-style Vertical Flow Pond outlet channel, and

-- Installing an inlet pipe into the Auto-Flushing Vertical Flow Pond for flow measurements.

Water monitoring indicates that the treatment system is working extremely well after 9 years. Fish were even observed in the final settling pond! 

Visit the Slippery Rock Creek Watershed Coalition for more information on programs, initiatives, upcoming events and how you can get involved!

(Reprinted from the latest The Catalyst newsletter from the Slippery Rock Creek Watershed Coalition.  Click Here to sign up for your own copy.)

Related Article:

Slippery Rock Creek Watershed Coalition: Nature’s Not Closed!

[Posted: June 27, 2020]  PA Environment Digest