Deer Run has been idled since elevated levels of carbon monoxide were detected on March 26. The unplanned shutdown was in its 67th day on June 1, and no one is predicting publicly when the mine will be restarted.

Neither the federal Mine Safety and Health Administration (MSHA) nor the Illinois Department of Natural Resources (DNR) has publicly released actual CO readings that officials say have risen and fallen sporadically since the forced idling. St. Louis-based Foresight has claimed the presence of CO in the mine has been at or below “ambient levels” for most of the past two months.

It briefly appeared in mid-May that Deer Run was moving toward an authorized restart after CO levels again dropped and an assessment team that entered the mine said it did not discover whatever had caused the higher readings. MSHA, however, has suspected a fire or “hot spot,” perhaps in a mine rib, may have been responsible.

In July 2014, a fire cost Deer Run an estimated 500,000 tons of production, according to a report by Cowen and Company.

Hopes for a reopening, perhaps by the end of May, were shattered after Foresight in late May resumed pumping nitrogen into the area that was thought to be the culprit, according to DNR spokesman Chris Young.

In DNR’s latest update, on May 28, Young said there had been no change in Deer Run’s status. “No plans have been submitted or approved yet that would allow the mine to return to operation,” he added.

Foresight stuck to its statement of May 22 that said efforts to restore operations at Deer Run were ongoing. “Foresight’s company personnel continue to coordinate with federal and state authorities to examine and monitor the mine, address the cause of the elevated carbon monoxide levels, and safely resume operations,” it said. “Foresight does not have an estimate of the timeline on which Deer Run mine will resume normal underground operations.”

The mine already has lost more than a million tons of production since the idling, based on its roughly 650,000 tons per month output in both January and February.

Deer Run produced 5.5 million tons in 2014. In Illinois, Foresight also owns the Pond Creek and Sugar Camp longwall mines and the Shay No. 1 continuous miner operation. The company produced a little more than 22 million tons in 2015, both for domestic and export markets.