Study shows Pinedale water contamination mostly unrelated to gas drilling

Dec 6, 2013

Pollutants including benzene and diesel-range organics have shown up in water wells like this one in the Pinedale Anticline for several years.
Pollutants including benzene and diesel-range organics have shown up in water wells like this one in the Pinedale Anticline for several years.
Credit Courtesy Linda Baker

Pollutants have been showing up in water wells in the Pinedale Anticline gas field since 2006. Until recently, no one knew where the contamination was coming from. Now, the Bureau of Land Management and Department of Environmental Quality have released a report indicating that most of the problem was not caused by energy production. Wyoming Public Radio’s Willow Belden reports.

WILLOW BELDEN: The investigation found that a lot of the contamination occurred naturally. Basically, underground gas worked its way up through the geologic layers and into the groundwater. The report says other pollutants came from materials used in installing water wells.

Kelly Bott represents Ultra, Shell, and QEP, three of the energy companies operating in the Pinedale Anticline. She says the study shows that operators are doing things right.

KELLY BOTT:  We’ve got a number of industrial practices that are in place to protect groundwater, and this study really validates those practices.

BELDEN: There were a few exceptions in the findings. In one instance, contamination could be traced back to an abandoned gas well. And a handful of water wells lacked the equipment necessary to ensure that contaminants from, say, storage tanks, don’t get into the water. But industry standards have been revised to deal with many of these issues.

Merry Gamper with the BLM says there’s more good news. They’ve determined that groundwater in the area moves very slowly. Gamper says that means contamination also moves slowly.

MERRY GAMPER: Should a contaminant be released … in like 100 years, that contaminant likely would not move greater than 150 feet. … So we wouldn’t expect a five-mile by 30-mile-long contamination plume except if every well on the Anticline was leaking.

BELDEN: The company that compiled the report concluded that no additional mitigation measures are necessary, to deal with water problems in the Pinedale area.

BRUCE PENDERY: It would still be a mistake to … not pursue mitigation in the area.

BELDEN: Bruce Pendery is an attorney for the Wyoming Outdoor Council.

PENDERY: Oil and gas development uses a wide array of chemicals, some of them quite toxic – known carcinogens and that kind of thing. And so I think care – the precautionary principal, if you will – should continue to really guide mitigation efforts out there.

BELDEN: Merry Gamper says the BLM is proceeding with care.

GAMPER: There are some things that we need to look at a little closer. Things are good on the Pinedale Anticline; there’s no question there. But it does not mean that they can’t be better.

BELDEN: Gamper wants to do more field testing, to be extra certain that no gas wells are leaking. And she wants to take a close look at things like well casings, to make sure they go deep enough to protect usable groundwater.

The BLM also plans to create a new monitoring and mitigation plan for the Pinedale Anticline. Gamper says that will help prevent future pollution, and enable them to detect problems more effectively.

Despite all that, some Pinedale residents feel regulators are not doing enough to protect groundwater. Linda Baker with the Upper Green River Alliance has seen a lot of changes in her area, and some environmental damage, related to energy development. So she’s skeptical. She points out that although most of the contamination has been documented at very low levels, several wells had high levels of hydrocarbons.

LINDA BAKER: And yet only approximately half were entered into the DEQ’s Voluntary Remediation Program.

BELDEN: The Voluntary Remediation Program, or VRP, is meant to get companies to clean up contamination when it occurs at high levels – that is, levels exceeding state standards.

LINDA BAKER: I don’t understand why the DEQ hasn’t entered all of those wells into the VRP program.

BELDEN: DEQ’s Deborah Harris says there’s a good reason: In some wells, high levels of contamination were detected only once, not in any follow-up sampling. She says when that’s the case, there’s a good chance that the one high reading was a fluke.

DEBORAH HARRIS: The laboratory analytical methods – you know they’re pretty good. But you have to remember that people are out in the field doing the sampling. Maybe their truck was running nearby. We all know that an automobile engine runs on hydrocarbons. So it could have been something as innocuous as that.

BELDEN: Harris says not to worry – if a well consistently shows high levels of contamination, remediation does happen. Always.

And regulators say industry is taking steps to prevent future pollution. For example, they no longer use lubricants containing hydrocarbons when installing water wells. And they’re required to use special equipment to prevent outside pollutants from entering wells. The BLM will consider instituting additional rules in its new monitoring and mitigation plan, though it’s not clear when that plan will be finalized. For Wyoming Public Radio, I’m Willow Belden.