America’s Coal Mine Pollution: A Clean Energy Solution

Across Appalachia, rust-colored ‌water ⁢seeps from abandoned‌ coal‌ mines, staining rocks orange and coating stream beds with metals. These acidic discharges, known as acid mine drainage, are among the⁣ regionS most​ persistent environmental problems. They‍ disrupt⁣ aquatic life, corrode pipes and can contaminate drinking water⁣ for decades.

Though, hidden in that ⁣orange drainage are valuable metals known as ‍rare⁢ earth elements that are ‍ vital for many technologies the U.S. relies on, including smartphones, wind turbines and‍ military jets. In fact, studies have found that the concentrations ⁢of rare‍ earths in acid mine waste can be comparable to the amount in ores mined ‍to extract⁣ rare earths.

Scientists estimate that more than 13,700 miles ‍(22,000 kilometers) of U.S.streams, predominantly in Pennsylvania‌ and West Virginia, are contaminated with acid mine discharge.

We‌ and our colleagues at West Virginia University have been working on ways to turn the ​acid ⁣waste in those radiant orange creeks into a‌ reliable ⁤domestic source for rare earths while ⁤also cleaning the ‌water.

Experiments show extraction ⁤can work. ​If ⁣states can ​also sort out who owns that mine⁤ waste, the environmental cost of mining might help power a clean energy future.

Rare earths​ face a‍ supply chain​ risk

Rare earth elements are a⁣ group of 17 metals, a

Turning a mine waste problem into a solution

Acid ⁤mine drainage forms ⁣when sulfide minerals, such as pyrite, are exposed⁢ to air​ during mining. This creates sulfuric acid, which then dissolves heavy metals such as copper, lead and mercury from surrounding​ rock. The metals end up in groundwater and ⁤creeks, were iron in the mix ‌gives ‍the water ‌an orange color.

Expensive treatment systems can neutralize the acid, with the dissolved metals settling into an orange ‍sludge in treatment ‍ponds.

For decades, that sludge was treated as hazardous waste and hauled‌ to‌ landfills.But scientists ‌at West Virginia University and the National⁤ Energy Technology Laboratory have found that it contains concentrations of rare earth elements comparable to those found in mined ores. These elements are also easier to extract from acid mine waste because the acidic water has already released them from the surrounding rock.

Experiments have shown how the metals can ​be extracted: Researchers collected sludge, separated out rare earth elements using water-safe chemistry, and then returned the cleaner water to nearby streams.

It is like ‍mining without digging, turning something harmful into‍ a useful resource.If scaled ‍up,this process could lower cleanup costs, create ​local​ jobs and strengthen America’s supply⁢ of materials ‍needed for renewable energy and‍ high-tech manufacturing.

But there’s a problem: Who owns the recovered minerals?

The ownership question

Traditional mining law covers minerals⁣ underground, not⁣ those extracted from water naturally running off abandoned mine⁣ sites.

Nonprofit watershed groups that treat mine waste to ‍clean up ‍the water often‍ receive public funding meant solely for environmental cleanup. If these groups start selling recovered rare earth ⁣elements, they could generate revenue for ‌more stream cleanup projects, but they might ‍also ‍risk‌ violating grant terms or nonprofit rules.

To better understand the policy challenges, we ⁣ surveyed mine water treatment operators across pennsylvania and West Virginia. The majority‌ of treatment systems were under landowner agreements in which the operators had no permanent property rights. Most operators said “ownership uncertainty” was one of the biggest barriers to investment in the recovery of rare earth elements, projects​ that can⁤ cost millions of dollars.

Not surprisingly, water treatment operators who⁢ owned the land where treatment was taking pl

This article is republished from The Conversation under a Creative Commons license. Read the⁤ original article.
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