Rivers can be cleaned up by neutralizing the acidity of AMD, but it's an expensive process. But two professors at Ohio University have come up with a way to fund the clean-up of polluted rivers by extracting the iron oxide -- a substance commonly used to make pigments -- and turning it into artist-grade paint.
Coal was once an important part of Ohio's economy and the state produced approximately 2.35 billion tons
from its underground mines between 1800 and 2010. But before 1977, when the US introduced the Surface Mining Control and Reclamation Act, mines that were no longer needed were often simply abandoned.
As a result, many of the mines have become polluters, with AMD affecting 1,300 miles of Ohio streams
, according to the Ohio Department of Natural Resources.
Guy Riefler, an environmental engineer and Ohio University professor, has been working to tackle the problem for the last 15 years.
"It's a nuisance and an eyesore and an embarrassment really to the population. And because it's a poor area, it really doesn't get the attention it deserves," Riefler explains.
Riefler landed on the idea of extracting iron oxide from the polluted water and turning it into color pigments, which could be sold to further fund the clean-up of AMD. But he didn't know enough about paints to determine what made them good quality.
Coincidentally, a decade ago, Ohio University art professor John Sabraw went on a faculty tour of acid mine discharge sites and experimented with making paint from a jar of polluted stream water -- without much success.
The pair began working together to turn extracted iron oxide into artist-quality paint. Their collaboration has helped take the idea from "an interesting little science project" to something bigger, as Riefler developed a small-scale process to neutralize the acidity of contaminated streams and extract iron oxide particles -- which he says is the predominant metal pollutant in Ohio's acid mine seeps.
"The modern artist is very good at engineering solutions to problems," he says. "I can't tell you how many times I got to a roadblock and I bounce it off John ... he'd come up with something that I didn't think of and just took us to the next level."
In 2018, alongside local non-profit Rural Action
, they partnered with paint company Gamblin to create a limited run of 500 oil paints. They were offered as a reward for supporters of the Kickstarter campaign that funded their research-scale pilot facility. Named the "Reclaimed Earth Colors
" set, the paints were popular amongst artists, says Sabraw, allowing them to incorporate an environmentally conscious aspect in their work.
Through their social enterprise called True Pigments
, they are now putting their clean-up model to the test by building their first full-scale treatment facility, due to be operational in 2024. It will be located at the Truetown discharge, at the Sunday Creek Watershed, a site in southeastern Ohio heavily impacted by AMD, according to Riefler.
"Every single minute, 1,000 gallons of water is coming out of this abandoned mine. It's got a lot of iron and it's acidic," says Michelle Shively MacIver, True Pigments' director of project development. "Very little life can live in an area that looks like this."
Once the treatment facility is operational, True Pigments aims to extract approximately 2 million pounds of iron oxide per year and clean up seven miles of stream -- starting from Sunday Creek to the opening of Hocking River -- according to MacIver.
A previous Rural Action AMD remediation project that neutralized the acidity of stream water on the west branch of Sunday Creek saw 17 species of native fish
return after two years, according to the NGO. True Pigments is confident that its facility will lead to a similar outcome in the Sunday Creek watershed.
"Our hope is that once the chemistry is fixed there, they (fish) will keep swimming upstream. That will be good for the entire watershed," MacIver says.
"It's an expensive issue"
True Pigments is not the first to extract iron oxide pigments from pollution. The EnvironOxide
range of pigments has been made from AMD in neighboring Pennsylvania for two decades, but Riefler says True Pigments uses a different method that needs less space and is better suited to the conditions at Truetown.
True Pigments has received funding from a number of donors including the Ohio Department of Natural Resources (ODNR), which has granted the project $3.5 million through its Federal Abandoned Mine Land Reclamation program
. The money will go towards the first phase of constructing the treatment facility.
Ben McCament, abandoned mine land program manager at the ODNR, says that between 1999 and 2018, the department spent approximately $32 million on 67 projects to treat AMD. "It's an expensive issue," McCament tells CNN. "I think that's always been one of the main challenges. Every site is unique, every site is difficult, and it requires long-term funding to treat it."
By funding True Pigments, the ODNR hopes to illustrate that through a public-private venture, "we can create a product out of these waste streams and then also address an environmental issue and recover and improve water quality that's been affected by AMD for a long time," McCament says.
As well as helping the environment, the hope is that the Truetown facility will provide jobs for the local community, and create a supply of iron oxide for other uses -- such as the construction industry, where it's used in bricks, colored concrete and tiles.
McCament believes True Pigments' model could potentially be a solution for AMD sites around the US, as long as they have "the right conditions that would make this particular approach workable, sustainable and economical."
Riefler echoes this sentiment. "With a little bit more work, it could be adapted to a lot of different places," he says. "So it's a first step, and it's a big one. It's got promise for pollution around the world."