The United Mine Workers of America Health and Retirement Funds sent a letter to retired miners warning them that their health benefits won’t continue after May 1, 2017, if Congress doesn’t act by the end of April.

In December 2016, Congress voted to temporarily extend a pension and benefits fund that would provide retired union miners cradle-to-grave benefits. The fund was established in 1946, when coal companies and the government agreed to provide retired miners cradle-to-grave-benefits.

Many coal companies have since sought bankruptcy protection, and are no longer legally obligated to pay into the fund, which is now running out of money.

Congress has yet reach a permanent decision on how to sustain that fund.

Republican State Senator Shelley Moore Capito said that while the letter retired miners received Wednesday is disheartening, she remains optimistic.

“We made a promise a long time ago that they were going to have lifelong health care benefits,” she said. “We are going to fulfill that promise and hopefully by April, so nobody will lose their healthcare.”

In an email statement, Democratic State Senator Joe Manchin said he is furious that retired miners received the letters, and called on Congress to act faster.

“When only a four-month extension passed in December, I promised them that this body will not abandon them,” he said in the email. “We will keep working to find a solution that is worthy of them. I refuse to let them down.”

In 2015, Manchin introduced the Miners Protection Act to Congress. The Act would reallocate money from the Abandoned Mine Lands Reclamation Fund to a fund that would support the pensions and health care benefits of coal miners and retirees. Capito co-sponsored the Act.

Senate Republicans are hesitant, however, to support the Act and bail out unionized workers.

This story was originally published by West Virginia Public Broadcasting.