It has been roughly twelve years since fracking launched the great shale rush in the U.S. and the biggest problem with the technology — how to safely dispose of the enormous quantities of toxic waste generated — remains unsolved.

In particular, regulators have struggled to fully understand or police the hazards posed by radioactivity found in fracking waste.

The most common form of radioactivity in shale waste comes from radium-226, which happens also to be an isotope that takes the longest to decay. To be exact, radium-226’s half-life of roughly 1,600 years means that well over a millennium and a half from now, more than half of the radium that fracking brings to the surface today will still be emitting dangerous radioactive particles.

Concern about the waste has taken on renewed urgency in light of a detailed report published in Environmental Health Perspectives (EHP), a peer-reviewed scientific journal which is backed by the National Institutes of Health. The study concluded that worrisome and extensive gaps in federal and state oversight of this radioactivity problem still persist.

“At the federal level, radioactive oil and gas waste is exempt from nearly all the regulatory processes the general public might expect would govern it,” the researchers wrote. “State laws are a patchwork.’”

This is not an entirely new finding. Several years ago, a New York Times investigative piece highlighted how the oil and gas industry routinely dumped radium-laced waste water into rivers. State regulators in Pennsylvania and the oil and gas industry adamantly denied there was a problem.

So what’s changed? The recent academic study concludes that even several years later, worrisome oversight lapses remain. As such, the researchers wrote, there is continuing reason for concern.

“We are troubled by people drinking water that [could potentially have] radium-226 in it,” David Brown, a public health toxicologist with the Southwest Pennsylvania Environmental Health Project, told the researchers (insert in original). “When somebody calls us and says ‘is it safe to drink our water,’ the answer is ‘I don’t know.’”

But there is more that makes this recent study important. Much of the public’s attention has focused on the hazards of 280 billions of gallons of radioactive wastewater generated every year by drillers. Regulators have found it difficult to keep tabs on how that waste is handled or how it is disposed, often relying on data self-reported by drillers. A study last year found that over half of Marcellus wastewater still winds up sent to treatment plants that discharge into rivers and streams.

However, in order to truly keep tabs on all of the radioactive materials from fracking, it’s necessary to understand that the radium often winds up accumulating on the surfaces it comes into contact with — dirt, pipes and holding tanks.

Some of the researchers’ most interesting findings come from a little-noticed study published in 2013 that found that the soil in fracking wastewater pit soil can carry elevated levels of radioactivity, even after drillers pull up stakes and complete their cleanup efforts.

In that 2013 study, Alisa Rich, professor at the University of North Texas’s School of Public Health, and Ernest Crosby, who spent 28 years as a engineering professor at the University of Texas at Arlington, took a look at the wastewater impoundment pits where drillers often store wastewater before trucking it away for treatment, injection underground or recycling.

Although the study was quite small, based on just two sites on farmland in Texas, its findings were striking.

One of the two pits tested was still actively being used to store fracking wastewater. The other was a site where a pit had been drained and the surface restored and leveled to match the surrounding farmland, where livestock feed was being grown, and the samples were taken from a depth of six inches.

They were surprised to find that the drained pit still showed elevated levels of radioactivity. They wrote:

Data from this limited field study showed elevated levels of alpha, beta, and gamma radiation to be present in reserve pit/sludge material and also in the soil of a vacated reserve pit after draining and grading to original topographic levels. Based on the use of the pit, the presence of radioactive materials was not anticipated. Agricultural land adjacent to the drained reserve pit may have an increased potential for radioactive material taken up in livestock feed crops growing on the land due to wind transport, runoff and migration of soil on adjacent land.

They cautioned, however, against inferring that all drained pits would show elevated radioactivity, explaining that the radioactivity could have been there before the pit was used to store fracking wastewater, in part because the oil and gas industry’s long history in the region meant that they did not know whether that land already had been contaminated before it was used to store wastewater.

Their unexpected findings indicated, however, that more research is needed into how adequate remediation is when it comes to wastewater impoundments, creating new questions about the adequacy of cleanup regulations for shale gas well sites.

In some states in the Marcellus region, where radioactivity levels are generally higher than in Texas, drillers are permitted to simply bury solid waste like wastewater impoundment liners on site. In West Virginia, for example, drillers may simply bury liners used to store wastewater from vertical gas wells, although they may be required to obtain a landowner’s permission if the well is horizontally drilled. 

The propensity for radium to accumulate also raises questions about the metal tanks, trucks and pipes used to transport fracking wastewater.

Combined with other elements like barium or strontium, the radium can form radioactive flakes on metal pipes used to transport the wastewater, for example, a problem that regulators refer to as pipe-scale. In filters, like the ones recently discovered illegally dumped in North Dakota, the radioactive materials can also start to build up.  If enough radium concentrates in one place, the radiation it produces can become strong enough to potentially penetrate a person’s clothing and skin, making it hazardous to simply be near it.

But the Environmental Health Perspectives review found that there is little oversight to protect workers from radioactive accumulation.

“Workers are covered by some federal radiation protections,” author Valerie J. Brown wrote, “although a 1989 safety bulletin from the Occupational Safety and Health Administration noted that NORM sources of exposure ‘may have been overlooked by Federal and State agencies in the past.’”

State regulators in Pennsylvania told the researchers that there was no evidence indicating that workers or the public faced a health risk from the radioactivity.

“But given the wide gaps in the data,” Ms. Brown noted, “this is cold comfort to many in the public health community.”

Photo Credit: The Earth, Oriented to Asia surrounded by barrels of nuclear waste, via Shutterstock.