At the Panther Creek plant in Carbon County, Pennsylvania, waste from old coal mines is used to power Bitcoin mining.

Cryptocurrency miner Stronghold Digital Mining has purchased the defunct coal power plant Panther Creek Energy Facility to power its Bitcoin mining farm. Millions of tons of residual coal waste piles up next to towns in Pennsylvania, polluting groundwater and releasing toxic gases.

Stronghold expects to clean up 4 million tonnes of coal waste from the Swoyersville site over a few years, potentially saving nearby residents from adverse health effects and paving the way for new development and open space.

The Pennsylvania Department of Environmental Conservation estimates that cleaning up all of the state’s abandoned mines will cost taxpayers more than $5 billion. So it’s happy to subsidize companies like Stronghold that are willing to help it out.