June 19, 2014
Cut open a hole in the ground, even a very narrow one, and you will be left with a pile of dirt. These are drill cuttings. Natural gas drillers in Pennsylvania’s Marcellus shale have a lot of these cuttings leftover. And therein lies a problem. Because that dirt is naturally radioactive, and there's a risk that radiation can get into water supplies if it isn’t properly treated.
The element of greatest concern is radium. That’s what Larry Shilling has to watch out for. Shilling is vice president of Casella Waste Systems, which runs the Chemung County landfill in New York, a few miles from the Pennsylvania border.
Sitting in a pickup truck at the landfill in southern New York, he watches trucks loaded with piles of dirt culled from deep shale wells in Pennsylvania crawl by.
“See this thing that says Ludlum?” Shilling asks, pointing to a pair of white tubes, each about five feet tall, sitting on posts at the entrance to the landfill. The machine is a Ludlum, Model 375P-1000.
In the business, it’s called a scintillating detector. It measures gamma radiation coming off of a dump truck. The readings feed into a small monitor inside the landfill’s office.
“They pull up, they stop, and as they drive onto the scales it registers what radioactivity might be in it,” he says.
Shilling points to heaps of wet black sand, wrapped in black plastic liners.
“The stuff with the plastic there?” he says. “That is the drill cuttings.”
The cuttings are actually a mixture of rock cut through the gas-rich Marcellus shale, fluids, called drilling mud, used to help bore the well, and liquids found deep underground. All this material comes up before a well is fracked—it doesn’t include fracking chemicals.
The landfill isn’t allowed to take cuttings that are too radioactive.
Shilling says they’ve never had a load of cuttings that exceeded acceptable levels of radiation enter the site. Three times the meter sounded, but all were getting radiation off the truck drivers. People who’ve had certain medical procedures can emit gamma radiation.
All rocks have some radiation in them. But the Marcellus Shale is an unusually radioactive underground formation. A recent study from the U.S. Geological Survey found it’s three times higher than other rock layers.
States in and around the fracking boom are working through what to do about all this natural radioactive waste from drilling.
New York may have a moratorium on fracking, but its landfills are taking solid waste from Pennsylvania drilling. Casella wants New York state regulators to let the company take even more drill cuttings from Pennsylvania.
But not everyone is convinced this landfill is taking sufficient precautions.
Gary Abraham is an environmental lawyer in Western New York working to block Casella from expanding its landfills. Abraham says there’s so much radiation in the deep shale rocks that it must inevitably be getting into landfills. He points to radioactivity readings taken by New York state regulators of the salty water found in the Marcellus Shale. This water, which comes up during and after fracking, is called brine.
“Those readings show that the radioactivity of the brine is as high as 15,000 picocuries per liter. The background radiation at the surface of the earth in New York is about 1 picocurie per liter,” says Abraham.
Shilling says while brine can be more radioactive, the cuttings are benign. In fact, says Shilling, testing they commissioned on the Marcellus showed very little radiation in the cuttings.
“The highest reading we got from any of those four samples was 4.3 picocuries per gram, still under the cleanup standard EPA set for cleaning up sites,” says Shilling.
The difference: one is looking at the brine associated with the Marcellus Shale and raising the red flag, the other is just focused on the rock and giving the green light.
The natural radiation in the Marcellus, particularly in the brine that comes out of it during and after fracking, is well established.
Avner Vengosh is a geochemist at Duke University. He found radium in a Pennsylvania stream near a plant that processed fracking wastewater at 200 times background levels.
Vengosh says there’s a risk that once the radium locked deep underground gets into streams and rivers, it will make its way into fish and eventually into people.
“Radium is very similar to calcium and as a result it would accumulate in the bone and start radiation, which would lead to bone cancer,” says Vengosh.
The particular isotope, or form of radium found in the shale, radium-226, has a half-life of more than 5,000 years. So basically, once it gets into the environment, it’s there for good.
Since contaminants started showing up in streams, Pennsylvania has tightened restrictions on the disposal of wastewater.
But the treatment of solid waste at places like the Chemung landfill in New York concerns Vengosh.
“Every contaminant that’s being disposed into landfills, the solids, are subject to numerous attacks of acids and different chemicals, different solutions within the landfill. And they’re creating what we call leachate,” says Vengosh.
Leachate—it’s basically garbage tea. Anything that’s in the landfill—like radium—can get into it. What happens to the leachate?
It comes to places like the Chemung County sewer district in Elmira, N.Y.
Dan McGovern the plant’s chief operator, says the plant handles about 6 million gallons of wastewater a day. Only about 30,000 gallons comes from Casella’s landfill for treatment.
McGovern says the plant is only certified to do basic tests at their on-site lab.
They can check for solids, pH levels, dissolved oxygen and salts. But, do they test for radium?
“No,” says McGovern. “(Casella) would actually have to send it out to a very sophisticated lab to test it.”
The treatment plant tests the water when it comes in and when it goes out, into the Chemung River, but never for radiation.
Casella does a quarterly radiation test of its leachate, says Shilling. Results from reports filed with the state showed low levels of radium-226 in the leachate, but with each testing, there was a small increase.
In New York, Marcellus Shale drill cuttings are exempted from the regulations governing low-level radioactive waste. If they weren’t, landfills couldn’t take them. And the leachate would have to go to specialized treatment plants that can handle hazardous waste.