The Marcellus Shale Coalition’s (MSC) lawsuit against Pennsylvania’s regulatory overhaul for unconventional natural gas producers will advance with most of the rules that the industry challenged still on hold after the state Supreme Court last week affirmed an order issued more than a year ago to stay some of them.

MSC filed its lawsuit less than a week after the regulations went into effect in October 2016. While the organization was involved in crafting some of the new rules, it targeted the regulatory packages’ core provisions, arguing that they were a burdensome overreach, unenforceable and contradictory to other applicable regulations and statutes. The state Commonwealth Court agreed in an order issued a month after the lawsuit was filed that enjoined the Pennsylvania Department of Environmental Protection (DEP) from implementing some of the regulations so it could consider the merits of MSC’s complaint.

The DEP appealed the order with limited success. The state Supreme Court affirmed the Commonwealth Court’s decision to enjoin part of the regulations’ public resources protection provision that would require operators to conduct a review of the impacts drilling would have on schools, playgrounds and species of special concern. The high court also affirmed injunctive relief for the rule requiring operators to monitor and remediate orphaned or abandoned wells.

The DEP, however, can now enforce standards for existing impoundments after the justices reversed a stay on part of the regulatory package that requires operators to register existing impoundments and upgrade them with a synthetic, impervious liner. The high court also reversed the lower court’s stay on more stringent well site restoration standards that would require operators to develop an erosion and sediment control plan that complies with the Clean Streams Law.

MSC had argued that the requirement is excessive and not even mandated by the Clean Streams Law.

The DEP began drafting the regulations about six years ago in response to Act 13, which was passed to update the state’s aging oil and gas laws. The agency split the rulemaking process for the conventional and unconventional industries, but lawmakers eventually passed legislation to scrap the conventional rules and ordered DEP to start those over.