STORY: As cryptocurrencies explode in popularity, so has the amount of electricity required to mine the digital tokens, which raises concerns about the impact crypto has on the environment.

But for Stronghold Digital Mining, a company based in western Pennsylvania, mining bitcoin could actually be a way to reduce environmental waste and clean up their community.

The company burns leftover harmful waste from abandoned coal mines to generate the electricity that powers hundreds of supercomputers running around the clock to mint bitcoin – an imperfect solution to energy generation but one that mitigates a century-old coal waste problem in Pennsylvania.

Stronghold CEO Greg Beard:

"We're taking a legacy problem that's more than 100 years old in western Pennsylvania and actually the entirety of Pennsylvania, and we're cleaning up this legacy problem.”

More electricity is used annually to create bitcoin than is used in the entire country of Finland.

The electricity usage has ignited a debate about whether the amount of power needed is worth the potential environmental costs.

"The bitcoin mining network itself is the largest decentralized computer network in the world, and it is power hungry. So co-locating a bitcoin mining and a power plant makes a lot of sense."

Beard says there are more than 800 abandoned coal mining sites in Pennsylvania that are overrun with coal ash – the byproduct from burning coal to produce electricity.

"Pennsylvania is sort of ground zero for where coal has been mined for more than a hundred years and, before 1974, all of that coal waste wasn't required to be cleaned up.”

Coal ash can leach into groundwater and pollute waterways, and contains heavy metals considered by many to be carcinogens.

"This is very personal to me. I grew up on one of these waste sites. I grew up in a community like this. I've seen the despair and degradation that happens over the years."

Bill Spence is co-chairman of Stronghold Digital Mining.

"Right now, we're standing on the middle of the waste from the Russellton mining operation. Every ton of this material was brought up from underground. There's roughly 10 million tons of waste here that we're standing on."

Stronghold collects coal ash from the bygone mine and processes it at a waste coal processing facility where it is sorted, crushed, and burned to generate the electricity to power the company’s bitcoin mining operation.

"And we mine, you know, around five bitcoin a day today, and that number is increasing every day as we increase the number of servers we are running.”

Beard acknowledges that Stronghold’s solution to mine bitcoin using coal waste isn’t perfect as burning coal ash also releases carbon into the atmosphere.

Still, he noted that because the existing coal waste is extremely combustible, much of the ash would end up catching fire and burning regardless of collection.

Beard says that processing the coal ash removes some of the harmful chemical content, plus he says his business has created hundreds of new jobs in the region.

"You know, we've made a lot of progress in the past couple of years. And so I'm really proud of what we built. And I think, in a way, having the reclamation business and bitcoin coupled, we're really taking what's a new world, you know, blockchain crypto and using that to clean up what's a, you know, an old, old problem."