 -- Federal labor officials told lawmakers today that they have notified dozens of coal workers they should re-apply for black lung benefits because their claims were denied in part based on medical reviews by a controversial Johns Hopkins physician.

Letters and calls to 83 miners in recent weeks were part of a raft of remedies lawmakers said would help “level the playing field” for miners suffering from black lung disease.

“Let me reassure you, the Department of Labor is committed to improving the effectiveness of these programs,” said Chris Lu, Deputy Secretary of Labor, at a Senate hearing convened to look at reforms to the government’s black lung benefit program.

The hearings and the Labor Department action came after troubling questions about the federal black lung program were raised in a year-long ABC News investigation with the Center for Public Integrity. The reports focused on the difficulties coal miners faced collecting benefits from coal companies that were intended to help miners and their families if they contracted the deadly and debilitating lung disease.

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Sen. Robert Casey said at the hearing that he was appalled to learn that sick miners were being turned down for those benefits based in part on the medical opinions of a leading Johns Hopkins doctor. He noted that the news reports demonstrated examples of miners who were denied benefits based on doctors’ conclusions that they did not have severe black lung, only to have autopsies prove – after their deaths – that they had the disease.

“I am pleased with the Department of Labor’s efforts to begin leveling the playing field for black lung claimants, but there is still more that needs to be done,” Casey said.

Labor officials said they would begin to address an enormous backlog of unresolved black lung cases – believed to be more than 14,000 of them – by adding more than $2.7 million to the program’s budget. Casey urged them to seek a $10 million increase in the next federal budget “to not only stop the backlog from growing, but to actually begin reducing the number of backlogged cases.”

Sen. Tom Harkin (D-Iowa) also attended the hearing, and described the pain he experienced watching coal miners, including his father, suffering from what then was only known as the “miners’ cough.”

“After years of hard, dirty work powering our country, the least we can do in return is make sure that we give the miners a fair shot at accessing earned benefits,” Harkin said in a prepared statement. “But that fair shot has been out of reach for many of those miners.”

The most significant moves described by Labor Department officials Tuesday involved actions they had taken to address the possibility that X-ray readings by Dr. Paul S. Wheeler of Johns Hopkins – who was hired by coal companies to read films in black lung cases -- had skewed hundreds of cases against the miners. The ABC News/CPI report found that Wheeler had not reported a single instance of severe black lung in the more than 1,500 claims that the news outlets reviewed going back to the year 2000. Labor department officials said they were unaware of Wheeler's record until the ABC News report was broadcast.

In court testimony in 2009, Wheeler said the last time he recalled finding a case of severe black lung, a finding that would automatically qualify a miner for benefits under a special federal program, was in "the 1970's or the early 80's."

Labor Department Solicitor Patricia Smith called those findings "shocking."

At the hearing, Lu told the lawmakers that his department had identified 83 claims that had been denied within the past year and sent a letter to those claimants alerting them to the “new guidance on Dr. Wheeler’s X-ray readings.”

“The letter informed the claimants that they could request reopening of their claims, included the date by which they had to make the request, and told them that the request could be made either by telephoning or writing,” Lu said in testimony he submitted to the senate committee. “In four instances, the one-year modification deadline was quickly approaching, so [the department] telephoned the claimants in addition to sending the letter. To date, 13 claimants have sought modification in response to OWCP’s letter.”

Lu added that the department had identified approximately 1,000 claims filed by miners between 2001 and 2013 that contained Wheeler X-ray interpretations. In those cases, miners were encouraged to file a new claim.

Hopkins suspended Wheeler's black lung unit a few days after the ABC News/CPI report was broadcast and posted online. Hopkins said it would conduct its own internal investigation, which a spokesperson said remains ongoing.

"We take these allegations very seriously and are still conducting the investigation into the [black lung] program," Hopkins spokeswoman Kim Hoppe said in a June email. "While our investigation is ongoing, nobody at Hopkins -- including Dr. Wheeler -- is performing" black lung X-ray readings.

Reached by phone in June, Wheeler said he hopes to be cleared by the internal Hopkins investigation -- which he said is being conducted by the Washington, D.C., law firm Patton Boggs. "The hospital still believes in my approach," he said.

Wheeler told ABC News then he was unmoved by the Labor Department bulletin. "They're not doctors," he said. "If they were from qualified medical institutions, I would be very unhappy."

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