A bipartisan group of lawmakers representing coal states renewed a push Tuesday to shore up pensions for thousands of miners whose companies went bankrupt.

The group, led by Sen. Joe Manchin, D-W.Va., introduced a bill that would use excess funds from the Abandoned Mine Land Fund, meant for mine cleanups, and borrow Treasury Department money to pay for retired miners' pensions each year.

Congress this year approved legislation guaranteeing healthcare benefits to about 22,600 coal miners and their families whose companies faced bankruptcy. But the agreement did not address the miners' pension fund, which is near insolvency.

The new bill, called the American Miners Pension Act, protects the pensions of nearly 87,000 current beneficiaries and another 20,000 eligible coal miners with vested pensions. The money borrowed from the Treasury would be paid back in 30 years, the bill proposes.

"We have come together today to deliver on an unfinished promise," Manchin said at a press conference Tuesday. "These miners earned their pensions through a lifetime of the hardest work imaginable. They did so safe in the knowledge that they would find it waiting for them down the road for support in their retired years. Let's finish what we started and pass this fix to ensure our coal miners keep their hard-earned pensions."

Sen. Shelley Moore Capito, R-W.Va., and Reps. David McKinley, R-W.Va, Peter Welch, D-Vt., and David Norcross, D-N.J., joined Manchin in introducing the legislation.

Similar bills on miners' pensions have seen strong bipartisan support in both the House and Senate, but Republican leaders never brought the legislation for a floor vote.