In the absence of federal regulation of hydraulic fracturing, many state and local governments have stepped up to regulate and limit the practice.

For instance, Vermont became the first state to ban hydraulic fracturing on May 17, although it’s been noted the state has no drilling projects underway. Since 2008, New York, which sits upon the natural gas-rich Marcellus Shale formation, has had a moratorium on fracking in place until its environmental authority completes an environmental impact review. Another Marcellus state, Pennsylvania, has welcomed fracturing, but Philadelphia has banned it.

“It’s really interesting how this is playing out on a local level in Philadelphia,” says Amanda Leiter, a law professor at American University. “States are doing quite a lot, and I would expect that as they will become more aware of the potential risks and start to think seriously about what to do.”