Clean streams lead to green art

Local artists use acid mine runoff to create glazes

By T.C. Conner/Allied News Correspondent

Is there gold in “them thar hills?”

You probably remember your American history lesson on the California Gold Rush of 1849. Soon after the initial discovery of gold by James Marshall, word got out and the rush was on as thousands of men, women, and children began migrating to California from points east, north, south, and even from across the Pacific Ocean.

These early prospectors were called “forty-niners” (in reference to the year 1849) and all had dreams of becoming millionaires. Some found great wealth, others returned home empty-handed. It’s analogous to present-day success stories: One might recognize the great innovators and prospectors of our time as being a new breed of “forty-niner;” perhaps they could become known as “two-thousand-niners.” Could abandoned mine sites of western Pennsylvania become destinations for today’s gold diggers?

Gold might not be in the hills of western Pennsylvania, but something worth its weight is: Manganese and iron oxide.

Just ask potter Bob Isenberg. Isenberg uses manganese and iron oxide recovered from acid mine drainage in some of the glazes for his pottery. And with help and guidance from Tom Grote, project facilitator with Clean Creek Products – a sub-division of Mars-based Stream Restoration Inc. – Isenberg has created a unique blend of glaze that enhances his pottery and sets it apart as a Western Pennsylvania exclusive.

Pottery has a long history and dates back thousands of years. Some of the earliest pieces are from the Czech Republic. A figurine discovered there has been aged at 25,000 to 29,000 years. Glazes containing manganese and iron oxides that are used in pottery-making have been around almost as long, but until recently these minerals were never extracted from acid mine drainage. Normally, manganese and iron oxide are mined from sites in Indiana, Montana, Michigan and other states.

Isenberg, who turns clay into unique artwork at the Pottery Dome in Springfield Township, has been using four different mixes of glazing compounds that contain manganese and iron oxide collected and recovered from passive treatment systems for acid mine runoff within the Slippery Rock Creek Watershed (SRCW). This “mining” process takes a negative mining byproduct – the manganese and iron oxides – and turns it into something used to create works of art.

Acid mine drainage is an ongoing environmental concern in Pennsylvania. Streams and creeks within the SRCW are still being affected by nasty chemicals in water seeping from abandoned mines. Stream Restoration Inc. constructs specialized passive treatment systems, which clean the manganese and iron oxide from polluted streams. These systems are making an impact and are beginning to restore sections of waterways that were once so polluted they couldn’t sustain aquatic life.

These treatment systems are also capable of “storing” manganese and iron oxide until they are cleaned and/or removed from filtering agents. Filtering agents include vertical flow pond systems, man-made wetlands and a special “wash dump” where manganese is allowed to collect.

It’s SRI’s collection process that allows Bob Isenberg and Tom Grote to create special recipes for glazes made from dried manganese: Vertical flow ponds are lined with limestone rock – much like that found in driveways – and mushroom compost, considered by landscape professionals to be a top grade soil additive. The limestone acts as a sponge for the manganese. After a period of years, it gets cleaned with a flip-screen bucket. This cleaning process releases the manganese and allows the limestone to be re-used.

“There were only five (flip-screen buckets) in the world at the time we purchased ours,” Grote said.

To collect the manganese, a hoe operator scoops limestone into a specially-designed rotating bucket. The limestone is submerged into a wash dump and the flip-screen bucket rotates. Centrifugal force prevents the limestone from falling out as it tumbles, and the manganese is “washed” from the limestone.

“We build a pond (wash dump) with a plastic liner, and as it flips in the water it’s washing the rocks,” Grote said.

Once the washing process is complete, the dump pond water is pumped into filtering bags. The water slowly seeps out, leaving behind slushy, wet manganese. The bags are then tied, numbered and marked with identifying characteristics, and stored. The manganese collected in these tote bags is dried and tested for mineral content.

SRI was able to find a way to recover the metals from these filtration systems after it received a grant from the Department of Environmental Protection’s Bureau of Abandoned Mine Reclamation.

“The abandoned mine passive treatment systems are trapping these toxic metals in the system, and after a period of time – 10, 15, 20 years – they’re going to fill. And when they fill up with the metals, the system will eventually fail,” Grote said. “At that point in time you have to clean the system.”

As a result of this process, Clean Creek Products is now marketing dried manganese and iron oxide as pigment coloring agents. Their rich earth-tones make them favorites among potters and crafters of ceramics.

What makes this process entirely unique to the SRCW is the fact that manganese collected in its passive treatment systems has particular characteristics that set it apart from commercially available manganese. Most manganese oxides used in ceramics and pottery glazes are imported.

The idea that it might be good for use in glazes was brought to the attention of Margaret Dunn, geologist and lead developer with SRI, by her close friend and professional potter, Pam Esch.

“Pam was in our office one day, about 2è years ago, and saw a container of manganese. She said, ‘Wow! That looks like the manganese I use in my glazes,’” Grote said. Dunn and others present realized they had found a possible use for both the manganese and iron oxide.

“We as designers and builders of abandoned mine drainage passive treatment systems – and not being potters – didn’t know that they used this stuff in pottery,” Grote said.

Clean Creek Products now offers for sale via their Web site (www.cleancreek.org) glass art and pottery made with glazes using manganese and iron oxide recovered from some of the 15 passive treatment system sites within the SRCW. A portion of the proceeds from each sale is donated to local watershed groups for their continuing efforts to clean and restore waterways and streams throughout Pennsylvania.

Isenberg also has pottery on display at the Pottery Dome (www.PotteryDome.co m) that was made using glazes that contain manganese and iron oxide recovered from a passive treatment site just north of Harrisville. He recently received iron oxide recovered for the first time from a passive treatment site near Jennings Environmental Education Center in Slippery Rock.

A special name is given to each glaze, identifying the treatment center it was recovered from.

While beautiful pottery glaze is a positive side effect of filtering these chemical compounds from local waterways, there are untold other benefits to having clean freshwater.

At a recent public meeting SRI held in Boyers to discuss their passive treatment systems, one gentleman who formerly opposed SRI’s work seemed to have changed his mind. Grote recalled what the man said: He “had to be 80 years old; he was a gruff old farmer. And you know people tend to be a little bit suspicious of new things, especially in this rural area. He said, ‘You know, I didn’t like what you were doing when you were putting that stuff in up here. I didn’t understand it.

“‘But I saw kids fishing off the bridge, right here in Boyers. And I’ve never seen kids fishing in that stream in my life until this year. There’s fish in the stream, so whatever you’re doing is cleaning up the stream – and that’s important.’”



Tom Grote can be contacted at Clean Creek Products, c/o Stream Restoration Inc., 434 Spring Street Ext., Mars, PA 16046; 724-776-0161; or e-mail ccp@cleancreek.org.

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