AUGUSTA — The Democratic-controlled Legislature’s rejection of new regulations for metallic mineral mining in Maine is drawing praise from environmental groups that say the proposed rules were flawed, but what’s next in the contentious debate over potential mining operations in the state remains unclear.

A 2012 law signed by Republican Gov. Paul LePage laid the framework for an overhaul of the state’s out-of-date mining regulations amid renewed interest in gold, silver, copper and other metals in Aroostook County’s Bald Mountain. But that effort hit a roadblock when lawmakers adjourned early Friday after refusing to sign off on the rules drafted by the Department of Environmental Protection, saying they were weak on protections for Maine’s environment and taxpayers.

That means that the state’s two-decades-old regulations will remain in place while officials potentially craft new rules with better safeguards, lawmakers said. The department said it’s reviewing what its next steps will be after the Legislature’s action, but said it stands by the strength of the regulations it created.

“We had thousands of hours dedicated to this from scientific experts within the department to ensure that these rules not only followed the law but had appropriate environmental protections,” Jessamine Logan, a spokeswoman for the department, said Friday.

Metallic mining has remained dormant in Maine for several decades, but New Brunswick-based J.D. Irving Ltd. has been exploring the possibility of mining on Bald Mountain and pushed for the overhaul of the state’s mining law, arguing that the old one was too restrictive.

Instead of approving DEP’s proposed rules — which lay out such things as where mining can take place in relation to bodies of water — the Legislature passed a bill that would force the department to rewrite and resubmit the regulations to lawmakers for consideration in 2016. LePage vetoed that bill.

Environmental groups said while the bill forcing the department to rewrite the rules failed, they see the Legislature’s ability to block the adoption of what they view as weak rules as a victory.

“Mining is a risky business. It’s a risky business for the environment and it’s risky for taxpayers,” said Pete Didisheim, advocacy director for the Natural Resources Council of Maine. “New rules need to do a better job of protecting our lakes, streams and groundwater from the pollution threat that’s caused by this particular kind of sulfuric mining.”

Democratic Rep. Joan Welsh of Rockport, co-chair of the Environment and Natural Resources Committee, said she expects the department will submit new regulations to the Legislature after the November elections.

“Our hope is that the department with be working with various stakeholder groups and the people who’ve had some real interests and that we will develop some good, strong mining rules,” she said.

Anthony Hourihan, director of land development for Irving, said the company is closely watching what happens with the rules as it determines whether mining at Bald Mountain would be a viable project.