A banner hangs in front of the entrance to Minntac Mine depicting a group of people holding hands and walking into a sunset. White writing across the top reads: “Safety is a family value.”
But some workers in the open pit taconite mines of Northern Minnesota say their safety has not been the top priority of companies and the Mining Safety and Health Administration (MSHA).
The concerns on the Iron Range are high rates of mesothelioma and lung diseases like silicosis.
Mesothelioma is commonly caused by asbestos exposure and silicosis by dust from crystalline silica or quartz.
On April 29, 2008 the MSHA tightened its limit on asbestos exposure. The limit had been in place for more than 30 years and was 20 times the Occupational Safety and Health Administration recommendation.
Silica recommendations have not changed since 1973.
Mining companies are in charge of monitoring the silica and asbestos fibers present in the dust created during mining. Some miners say monitoring done by the companies has been inadequate.
Twice a year, MSHA takes measurements of exposure levels in each mine, but miners do not receive the results.
‘A lot of gaps’
In 2008, the University of Minnesota received $4.9 million to study the possible link between mesothelioma and dust from taconite mining.
When University researchers began looking at historical records of exposures in the mines, they found a lot of pieces missing.
Dr. Gurumurthy Ramachandran, a professor of environmental health sciences and researcher, said MSHA and the companies monitored particulate levels very sporadically, which resulted in a lot of gaps and times when there was no data monitoring.
This is partially due to mines continuously shutting down and restarting, Dr. Jack Mandel, study leader and environmental health sciences professor, said.
Of the six mines on the Iron Range, two are temporarily not in operation due to economic constraints and low demand for steel, said Roger Holmstrom, a member of the Steelworkers Organization of Active Retirees.
It doesn’t do any good to monitor when you have nothing running, said the president of the U.S. Steel Union 1938, Mike Woods.
However, Woods said even when mines are in operation, the testing has been inconsistent.
Woods works at Minntac Mine, where he said testing by U.S. Steel is rare.
“They claim they do it, but they also claim there’s nothing up here that will harm anybody,” Woods said.
He said there have been a lot of complaints about dust problems in the mine’s crushing facility, and some complaints were made to MSHA. Dust is created in blasting, drilling and crushing of rock.
“If there are complaints they’ll [test] more often,” Woods said.
Woods said he hadn’t heard of dust complaints in the past year, but that doesn’t mean the problem was fixed. Minntac is running at reduced capacity, which might result in fewer complaints, he said.
Asbestos: no single definition
Scientists, regulatory agencies and companies have differing definitions of asbestos, Ramachandran said.
The outcomes are different when each group counts asbestos exposures, he said.
The Occupational Safety and Health Administration defines an asbestos particle as being at least 5 micrometers long, and having a length three times its width.
This definition does not take mineralogical aspects into account, Ramachandran said. Taconite fibers have a similar shape to asbestos and fit this definition.
The taconite fibers may have similar health risks to asbestos, but are not counted as asbestos by mining companies.
The Cliffs Natural Resources 2008 sustainability report found fibers at the Peter Mitchell Taconite Mine in the eastern Mesabi Range.
The report says “a small percentage of the host rock can fracture into tiny particles with a fiber-like appearance … all health studies performed to date have demonstrated that these particles do not cause diseases generally related to asbestos.”
36-year regulation remains
When crystalline silica, or quartz, is crushed into a fine dust it can cause silicosis, which inflames and scars the lungs.
The permissible exposure level of silica must be limited when the material being mined has a level of quartz of more than 5 percent, and the limit is calculated based on the amount of quartz present.
The quartz level on the western Mesabi Range is around 55 to 60 percent, according to the results of a 2001 study by University of Minnesota researcher and geologist Lawrence Zanko, who took 18 taconite samples from five mines in the area.
MSHA’s limit on silica was created in 1973 at the American Conference of Governmental Industrial Hygienists, and was designed to limit exposures to.1 milligram per cubic meter over eight hours, the Department of Labor said in a written statement.
The American Conference of Governmental Industrial Hygenists now recommends a 25 microgram (1,000 times smaller than a milligram) exposure limit, but MSHA’s limit remains unchanged.
The agenda said the National Institute for Occupational Safety and Health recommended a 50 microgram per cubic meter exposure limit.
MSHA’s Semi Annual Regulatory Agenda from May 2009 said the administration will look at changing the current limit in 2011.
The Federal Mine Safety and Health Act of 1977 mandated that the average concentration of respirable dust containing asbestos should be 2 milligrams per cubic meter of air within three years of the bill’s enactment.
The legislation remained in place for more than 30 years, while OSHA’s recommendation changed to 0.1 fibers.
Dave Trach, president of the District 11 Steelworkers Organization of Active Retirees, said during his time in the mines the organization had a lower tolerance for fibers in the air. While MSHA, which protected the miners working with asbestos, had limits that were “way the hell up there,” Trach said.
On March 20, 2008 Scott Howard, a miner from Kentucky, contested MSHA’s limits on silica.
The National Institute for Occupational Safety and Health recommended reducing the average exposure of dust containing silica to 0.5 milligrams during an eight-hour workday.
MSHA made the reduction an “objective” in 1998, but never enacted it. In 2001, it removed the goal due to “resource constraints” and are “changing safety and health regulatory practices,” according to the court document.
Lowering respirable dust levels was later removed from the agenda as well.
By 2008, both silica and respirable dust had made it back on the agenda, though only the objective about respirable dust was enacted.
MSHA also received recommendations from the U.S. Department of Labor’s Office of Inspector General to use electron microscopes to determine if an asbestos sample was above the permissible exposure level. MSHA rejected the suggestion.
Above the sunset poster at Minntac mine, a neon sign alternates messages, switching from the current temperature to “personal protective equipment is self defense.”
The mines use dust collection equipment and suppressants, like water, to regulate the dust, Woods said.
Trach recalls working with pipes covered with asbestos in the mines.
“Was I ever told in 38 years, there is a mask for asbestos?” Trach said. “No.”
Roger Holmstrom, who retired in 2003, was told if the dust was really bad to pick up a white mask.
Now, miners are required to carry respirators and wear them if the dust level goes above the limit.
The Department of Labor said in the written statement that they have been looking at Continuous Personal Dust Monitors for coal miners, which would give real time information on dust levels. The monitors would be primarily for coal miners, and would not measure quartz content in the dust.
When an MSHA inspector visits a taconite mine, the measurements they take are sent to a laboratory in Pittsburgh.
The Department of Labor said it takes “usually one to two weeks” for mines to hear back with information about exposures.
Woods said the samples are taken in little tubes, which are attached to the miner.
But Trach said during his time as a miner, he was never told what the samples had showed.