A few months ago, a Marcellus Shale operator approached Leong Ying, business development manager at the radiation measurement division of Thermo Fisher Scientific, with a problem.
The driller, whom Mr. Ying declined to name, was trying to dispose of oil and gas waste at area landfills but the trucks kept tripping radiation alarms.
Rejected trucks had to be sent back to well pads or taken out of state, both costly options. It was happening enough that it started nudging the company’s bottom line, Mr. Ying said.
“Once you hit them in the pocket, then they stand up and take notice,” he said.
Mr. Ying’s company is marketing a new radiation detector that can instantly categorize the different types of radioactive materials present in waste and their concentrations.
Today, the most likely solution to deal with radioactive oil and gas waste is to dilute it with non-radioactive materials, such as soil, and then send it to local landfills.
Mr. Ying said his client has built a multimillion-dollar facility specifically designed to treat such waste using a reverse osmosis process, which separates the water from the solids, where the radioactivity is concentrated. Those solids are then either spread out across truck loads, diluted and disposed of at local landfills, or taken to specialty facilities.
In the first half of this year, 421 trucks carrying oil and gas waste tripped radiation alarms at Pennsylvania landfills, according to the state Department of Environmental Protection. All but two of those trucks eventually dumped their waste at those landfills.
Last year, 1,015 loads set off the alarms, up slightly from 2012. Only five were subsequently asked to find another, more suitable, destination for low-level radioactive waste.
There were also 232 oil and gas related alarms that went off at waste transfer stations, which are facilities where waste is processed before disposal.
It’s likely that many, if not most, trucks bearing loads with high radioactive readings never show up at area landfills.
“A lot of companies are surveying before they leave a drilling site,” said Carl Spadaro, environmental general manager at Max Environmental, which operates two landfills in southwestern Pennsylvania.
“If it [sets off] alarms there, they’ll make a decision to send the truckload somewhere else. It’s in your best interest to scan before something leaves” the well pad.
Landfill alarms sound when a truck carrying waste registers at or above a dose rate of 10 microrem per hour above what is naturally in the air. That’s a measure of the potential of that waste to pose harm to humans.
The 10 microrem threshold is extremely low, according to Todd Brautigam, a Pittsburgh-based radiological specialist with Georgia-based Enercon. It’s about what the natural variation is for a particular location depending on time of day, weather and other conditions.
The DEP gives landfills an annual limit on how much of this waste they can accept.
Each load that sets off an alarm but comes in below 140 microrems per hour can probably still be disposed off in a landfill. It gets subtracted from a landfill’s annual limit based on a formula that takes into account the amount of the waste and exact dose rate.
For anything above 140, the landfill operator has to contact the DEP and the waste will have to find a different home, likely out of state. Anything below 10 microrem per hour gets counted as if it were a zero, raising some concerns about accumulation of this material over time.
There is no reliable mechanism for the DEP to keep track of how much oil and gas waste is going into state landfills. Landfill records, which are filed on paper, don’t give breakdowns of waste by industry. Drillers are required to report where they submit their waste electronically, but, as a recent Post-Gazette analysis showed, there is widespread underreporting and inaccuracies in that data.
Because of these discrepancies, it is also impossible to know how much oil and gas waste goes straight to out-of-state landfills that specialize in low-level radioactive waste. There are a few such facilities in Michigan, Idaho and Utah.
Oil and gas discards fall into the category of residual waste, a type of waste that has been growing in Pennsylvania. In 2010, the amount of residual waste tonnage accepted at Pennsylvania landfills shot up. The average weight of such waste since then has been more than a third higher than in the four years before.
The radioactivity in oil and gas waste falls under the category of “Technically Enhanced Naturally Occurring Radioactive Material,” or TENORM.
Drilling and fracking waste is far and away the biggest TENORM trigger for radiation alarms at Pennsylvania landfills. The landfills were required to install sensors in 2001 to monitor hospital-generated waste. But drilling and fracking waste comprised more than 85 percent of radiation alarms tripped over the past year and a half.
Drilling and fracking dredges up the uranium, radium, thorium, strontium and barium buried deep underground and brings them to the surface along with drill cuttings, drilling muds and flowback fluid and brine.
The majority of the loads tripping alarms are actually liquids that have been solidified into a sludge. They comprised more than three-quarters of radioactive loads last year.
David Yoxtheimer, an extension associate with Penn State University’s Marcellus Center for Outreach, said there might actually be less radioactive sludge going forward. Drillers are getting less picky about what’s in the treated water they reuse for fracking.
Whereas several years ago, many were telling treatment plants to remove as many metals as possible from the flowback in order to reuse it — those metals would then be condensed into the sludge that gets trucked to landfills — more recently operators are finding it’s as effective to frack with metal-laden water, so the radioactive elements remain in the fracking brew.
A long-awaited DEP study of radioactive material in oil and gas waste and its potential impacts on humans and the environment is scheduled to be released before the end of the year.
Anya Litvak: firstname.lastname@example.org or 412-263-1455.