NARRATOR: In the massive coal fields of Pennsylvania, the lingering effects of the mining industry can be seen in its rivers and streams.

One of the most polluted is the main stem of the Moshannon Creek, what locals call the Red Mo.

ERIC ROSENGRANT: I don't know when people started calling the Red Moshannon the Red Moshannon.

As a matter of fact, a lot of people think that's the actual name of it, but it really is just a nickname.

There are so many sources of mine drainage from top to bottom that come into the Red Mo.

It starts taking on that red color and it retains that color all the way to the mouth.

KELLY WILLIAMS: The Moshannon Creek Watershed is pretty large.

It's quite the task to handle and unfortunately, the majority of it, particularly the main stem, if not lifeless, there's very little life in it due to the mine drainage impacts.

NARRATOR: Coal mining fueled America's Industrial Revolution and built the economy of Pennsylvania.

But it also left behind thousands of abandoned mines that continue to pollute the environment with acid mine drainage.

The coal mine drainage is a challenge because so many of the operations that created the problem have gone bankrupt and aren't there anymore to deal with it.

And they've generated a pollutant source that could last for thousands of years.

NARRATOR: A team from Trout Unlimited monitors acid mine drainage and surveys the region's fish habitat.

But on the Moshannon Creek, the readings do not look good.

Alkalinity, zero, conductivity is really high, and pH is only 4.5.

We wouldn't find any fish here.

And go the next one.

NARRATOR: The truth is that people in this area have not seen trout in this stream for generations.

All the fish species and the bugs that they eat prefer to live life in a pH of six to eight.

So when you have acidic conditions, you have a lot of metals that are falling out in the water and they are coating the bottom of the stream.

That's taking up places where the macroinvertebrates, the bugs that our fish eat, that's where they live.

And so if they can't live there, then all of a sudden the food chain is disrupted.

Even if fish could survive there, there's nothing really for them to eat.

You start getting into mine drainage that's causing a stream to be pH three, two, no life wants to survive there.

The legacy of the coal mining operations has basically taken rock that was stable under a certain condition and now exposed it to air and water, leading to these reactions that produce this drainage.

NARRATOR: This is the air shaft of an abandoned, underground coal mine.

The orange water coming out of the ground is highly acidic and steeped with toxic heavy metals, principally iron, aluminum and manganese.

BILL BURGOS: What happens in coal mines is the pyrite or the iron sulfide minerals that are associated with the coal get oxidized to form sulfuric acid, and that sulfuric acid dissolves rocks around it and gives you the iron, aluminum, manganese.

So the challenge is to make acid mine drainage able to support life again.

And in order for it to support life, we have to raise the pH and we have to get metals to fall out of solution to become precipitates that we can then dispose of safely.

NARRATOR: It's a daunting challenge to treat acid mine drainage on Moshannon Creek.

There are thousands of discharges over a huge geographic area, and so far, little has been done.

There were very few people really looking at it with the serious eye toward recovering it, because it is so seriously impacted, very difficult to deal with, because there are so many discharges up and down the stream that a lot of people just threw their hands in the air and kind of gave up on it.

NARRATOR: But remediation is possible.

Just 35 miles away in neighboring Clinton County, the Trout Unlimited team is finding and collecting Brook trout in a stream called Two Mile Run.

It's a technique called electrofishing.

They deliver a mild shock to young trout to collect and measure them.

KATHLEEN LAVELLE: Due to the historical coal mining and the abandoned mines that are not currently being treated, Two Mile has been historically dead.

There hadn't been Brook trout in middle branch of Two Mile for over 100 years.

NARRATOR: Trout Unlimited pushed for the construction of a passive treatment system upstream, and now the trout have returned.

Brook trout, 124 grams.

These Brook trout are one of the best indicators that we can have-- that our treatment systems are working and that this stream is recovering from the mine drainage.

109 millimeters.

NARRATOR: That same hope is what drives the Moshannon Creek Watershed Association, a citizens action group working with volunteers, government agencies, nonprofits, researchers, and students.

They've gathered to map, test, and quantify discharges along Moshannon Creek, between Clearfield and Centre counties.

It's a beautiful day to sample acid mine drainage!

ERIC ROSENGRANT: And so you're starting at ground zero, so you have to identify all your discharges, you have to identify the volume of your discharges, the concentration of your discharges.

You have to decide which ones are you going to treat that are going to do the most good.

NARRATOR: Looking at Moshannon Creek tributaries like the veins of a leaf, you can see that the area to the West is adversely affected by acid mine drainage.

The data gathered will help to identify where to target future cleanup efforts.

In the case of Moshannon Creek, it's already known that there's three major reaches that are severely impacted by underground coal mines, and that if these three plants get built out over the next 15 years, that we could restore, essentially, the whole creek.

You know, we're talking 50, 60 miles of trout stream, very high quality trout stream could be recovered.

NARRATOR: To deal with abandoned coal mine drainage, the Moshannon Creek Watershed Association and its partners are moving ahead with plans to build new treatment plants along Moshannon Creek.

And as part of their coursework, teams of college students are helping to visualize possible solutions.

Today is the design showcase for all of Civil and Environmental Engineering.

And this semester, we're designing the three treatment plants required to reclaim Moshannon Creek.

CULLEN TALHELM: The water that's coming out of those mines is very, very bad, very heavily polluted with metals.

It's very heavily acidic.

And you can even see just looking at it that it's orange, like almost red because of how much iron is in it and how acidic it is.

It's nice to see results of what the students produced and that it's actually a real world problem that they're working on.

NARRATOR: Six student teams will write proposals for three acid mine drainage water treatment plants, to be strategically placed along Moshannon Creek.

Our team was given Sulfur Run near Winburne, PA. And our task was to look at the discharge points of AMD that were going into Sulfur Run, look at how they affect the Moshannon Creek, and find a way to solve that so that AMD isn't a problem anymore.

So here's the mines that are doing it.

We had to use the PA mine Atlas website.

We found six main discharge points split up between three different mines, mine 45 and then mine 46 and 47, which is a combined mine.

The Moshannon Creek Watershed Association, they give us the data, raw data points of influence sources, acidity, flow rates, all this stuff, and we average it all out.

And we compare these numbers to the effluent standards for the water, and see which areas we need to treat more than others and how drastic of a treatment we need to do for each of these areas to get the water to be clean and neutral.

The place we're going to place the plant is right on the shore of the Moshannon Creek, and it's right beside the existing wastewater treatment facility.

And it's just one large parcel.

It's all woods.

There's no houses to remove.

NARRATOR: Discharges into the creek can reach volumes of 3,000 gallons per minute.

So the students propose active treatment plants that can aggressively treat high volumes of acid mine drainage.

The way we solve this is by adding a caustic lime solution that oxidizes out some of the metals and just overall raises the pH.

It adds alkalinity to the water, basically.

And the way we get the metals out is we add this polymer that joins all the metals together, and then these heavy particles settle out of the water, and they settle down to the bottom.

Then we just have some natural polishing pond and wetlands to further allow those metals to settle out.

Once those get treated, most of the Red Mo will not be contaminated anymore, and I think it'll really bring back the trout and the fishing industry in this area.

I like what I see so far.

I think they've got some good ideas.

I think they are very similar to what will probably actually be built.

[applause] I think there's opportunities for everyone to contribute.

There could be such great revitalization of these areas if the water were clean.

NARRATOR: Abandoned coal mine drainage has plagued Pennsylvania for generations, but hope has arrived with new scientific discoveries.

Penn State professors Bill Burgos and Jennifer Macalady are part of a transdisciplinary research effort to find and develop more effective remediation.

We have a team of people that includes engineers, hydrologists, microbiologists, to do this important job that we have to clean up acid mine drainage.

NARRATOR: In current passive treatment systems, acid mine drainage is run through limestone channels to neutralize the acidity and remove heavy metals.

One major problem is that over time, the limestone becomes coated with iron particles, and must be replaced.

But the science and engineering team may have found a biological answer near the source of acid mine drainage in a place called the kill zone.

When you are traveling over landscapes in Pennsylvania that are affected by acid mine drainage, you often will see pretty large kill zones where there's no vegetation, there are dead trees, not much life, but the color is often very red.

And that red color is actually a result of treatment.

It's the result of iron being oxidized and being immobilized in what we're calling an iron mound.

What we find is a whole community of organisms that are, together, accomplishing this task of removing iron from solution while the pH remains low.

What we would like to see in the future is a combination of the existing types of passive treatment, in which we use natural microbial communities of the sort that are creating iron mounds.

Those communities can remove most of the iron at a low pH, and so that is really a magical ability that we can use as a component of passive treatment to improve their efficiency.

NARRATOR: In fact, mine reclamation professionals have already installed a feature in treatment systems called a terraced iron formation that mimics a natural iron mound and allows native microbes to treat the water.

For all the harm done by acid mine drainage, it's difficult to think of how it might help us.

But dissolved in its acidic waters, there are valuable minerals, minerals critical to clean energy technology.

And with a grant from the Department of Energy, a team of researchers at Penn State has set out to prove they can be recovered.

So this acid mine drainage has become a resource now for these minerals.

While we are treating the acid mine drainage for its acidity, we can also get these minerals.

NARRATOR: Some of the minerals found in acid mine drainage are highly important to national security.

For example, each F-35 fighter jet uses 920 pounds of rare Earth elements, which are 100% dependent on foreign imports.

Others are vital for clean energy technology in the transition to net zero.

Now if we want to go for sustainable energy, batteries depend on these critical minerals, cobalt, manganese, graphite and nickel.

Solar energy depends on some of these minerals.

Wind energy extremely depends on high, very powerful magnets.

And those magnets can only be possible using rare Earth elements.

NARRATOR: But how to recover each individual element so that it can be useful?

In the lab, the team devised a practical demonstration of their process.

We take the AMD as it is coming out, the acid mine drainage, which is at a low pH, and gradually raise the pH to take out each element at a different pH levels.

NARRATOR: Near the ceiling, they place a barrel of raw acid mine drainage, which will run through multiple stages of treatment before it hits the ground.

Each mineral has its own characteristics of when it will precipitate out.

At a pH of four, iron will start precipitating out.

And then we go to a pH of five, where aluminum will come out.

And then raise again to six and seven.

That's where all this group of rare Earth elements will precipitate out.

NARRATOR: At this point in the process, the water has reached the desired neutral pH of seven.

However, cobalt, and manganese still remain.

Normally, you would need to drop cobalt manganese up out at like pH ten, but they have found a way to drop it out at pH seven.

SARMA PISUPATI: At the same pH, we can get that cobalt and manganese, which are critical for batteries and then discharge the water.

That is the uniqueness of our process.

So we drop out the iron, drop out, the aluminum drop out the rare earths, the cobalt and the manganese, and then their treatment facility could just continue on and do the final processing.

NARRATOR: The next step is for the Center for Critical Minerals to build a pilot scale facility that can process 10,000 gallons of drainage per day to convince industry to adopt the technology.

SARMA PISUPATO: 200 years worth of coal mining will be powering the next 200 years of sustainable energy sources if we do it right.

JENNIFER MACALADY: So what we all imagine for our future, for a good future, trout returning, we have healthy streams, we have people that are not living near toxic water.

We want that future.

We all do.

And I think what it's going to take is a whole community of researchers and a whole community of citizens, really, and their government to clean up acid mine drainage.

We need citizen groups that are concerned about their watershed.

We need students who are curious about the way the world works and training to be future scientists themselves.

All of those components are what we need in order to make good progress on acid mine drainage.

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