Through a drilling technique known formally as hydraulic fracturing, a stratum of shale rock one mile beneath the surface is blasted with chemically laced, high-pressure water to release pockets of natural gas. That water, now containing mineral debris from the rock formation, is then sucked back out of the earth to be disposed of or recycled.
A constituent element of that wastewater is radium-226. The Marcellus shale is full of it.
Mark Engle, a U.S. Geological Survey research geologist, said the main reason the Marcellus shale is so high in radium is because the shale contains enriched concentrations of uranium, which has a half-life of 4.5 billion years. That means, Engle said, “these rocks will continue to generate radium and other uranium series progeny for a very long time.”
Engle co-authored a USGS report that found that millions of barrels of wastewater from unconventional (fracked) wells in Pennsylvania and vertical wells in New York were 3,609 times more radioactive than the federal limit for drinking water and 300 times more radioactive than a Nuclear Regulatory Commission limit for industrial discharges to water. He also said the Marcellus’ high levels of uranium and radioactivity has to do with the surrounding geology.
Marvin Resnikoff, a physicist at the University of Michigan and senior associate at Radioactive Waste Management Associates, said the Marcellus shale contains about 30 times the amount of radium found in topsoil sampled from New York and Pennsylvania.
And with higher levels of radium in the black shale itself comes increased levels of radium in wastewater, Resnikoff said.
While the radioactive materials contained within the Marcellus during fracking are naturally occurring, experts say high levels still pose a threat to health.
The EPA classifies radon, radium and uranium as “naturally occurring radionuclides found in the environment.” But the EPA also classifies both radium and radon as “potent carcinogens.” The agency says that radium, through oral exposure, can cause lung, bone, head and nasal passage tumors. And radon, if inhaled, causes lung cancer.
Resnikoff agrees.
“Radium is of concern because when ingested or inhaled, it concentrates in bone and can give rise to leukemia,” he said.
While the World Nuclear Association says that naturally occurring radiation makes up for the average person’s annual exposure and is usually not a threat, it also says that certain industries handle significant quantities of Naturally Occurring Radioactive Material, or NORM, which usually ends up their waste streams.
“Over time, as potential NORM hazards have been identified, these industries have increasingly become subject to monitoring and regulation,” the association said. “However, there is as yet little consistency in NORM regulations among industries and countries. This means that material which is considered radioactive waste in one context may not be considered so in another. Also, that which may constitute low-level waste in the nuclear industry might go entirely unregulated in another industry.”
That’s why the nuclear industry is subject to much stricter regulations than the gas industry in terms of regulating potentially radioactive waste, said David Lochbaum, a nuclear engineer who heads the Nuclear Safety Project for the Union of Concerned Scientists.
“NRC’s regulations require that every drop of water and every molecule of air discharged from a plant be monitored for radiation,” Lochbaum said.
Ivan White, a career scientist for the National Council on Radiation Protection, said radiation exposure to humans should be limited.
“The goal is to limit the total radiation dose to large populations because of the increased probability of health effects,” he said. “In the current case, the uncontrolled release of hazardous waste could result in the exposure of millions of people over decades.”
White also authored a report issued by the New York-based Grassroots Environmental Education that says fracking can produce waste much higher in radiation than previously thought.
And environmentalists say that radiation is becoming a serious issue in the disposal or treatment of fracking waste.
“The issue with oil and gas development — and especially fracking, given the large amount of fluids injected — is that the deep drilling and fracking bring these NORMs back up to the surface as drill cuttings and wastewater,” said Adam Kron, attorney for the Environmental Integrity Project.
“As fracking has rapidly expanded, we’re seeing much more of this radioactive waste, which is a problem, since traditional landfills and wastewater treatment plants aren’t accustomed to handling it,” he said. “In fact, wastewater treatment plants aren’t able to remove radioactivity, and we’re starting to hear accounts of landfills receiving — and sometimes turning away — radioactive cuttings and sand from across state lines.”
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