CHARLESTON, W.Va. (AP) — West Virginia’s coal mine cleanup fund has no known backup plan if it goes insolvent, according to a new state audit.

The legislative audit report released Monday said that mine reclamation program within the state’s Department of Environmental Protection is at risk of insolvency due to the risk of bond revenues not raising enough to guarantee the fund’s future.

Among several recommendations, the auditor calls on the department to not approve applications for permit renewals for companies that have not paid taxes for the special reclamation fund.

Its review found that 70 mining companies that filed coal reclamation tax returns were delinquent on $5.3 million in total funds.

Reclamation of shuttered coal mine sites is crucial to preventing environmental pollution and returning the land to its habitat. Contaminants can seep into waterways and harm wildlife if not properly handled after a mine closes.

“West Virginia’s coal mining reclamation program will continue to require hundreds of millions of dollars to reclaim permit sites in accordance with federal regulations,” the audit said. “The program has no known contingency plans if the reclamation funds were to become insolvent.”

Insolvency could also pose a dramatic hit to the state budget, and mismanagement of the funds could lead to federal control over the program, according to the audit.

The report calls for a legislative commission to study the state’s reclamation program and ensure its long-term viability.

Republican Senate President Craig Blair told the Charleston Gazette-Mail that lawmakers should aim to attract federal funding for the program. “Otherwise, we’re looking at a billion-dollar program of our own to begin with,” he said.

He added the miners who lost jobs in the industry can be employed to go back in and work on reclamation. “It’s a win-win scenario from that standpoint if we’ve got mines that are closing down,” he told the newspaper.