CASPER, Wyo. — Wyoming was one of 15 states in which oil and gas service companies injected hundreds of thousands of gallons of water containing potentially hazardous chemicals and known carcinogens into wells from 2005-2009, a report by three House Democrats said late last week.
The report said 29 of the chemicals injected were known or suspected human carcinogens. They either were regulated under the Safe Drinking Water Act as risks to human health or listed as hazardous air pollutants under the Clean Air Act.
Wyoming ranked fourth among states with at least 100,000 gallons of water pumped containing a carcinogen in the four-year period, with a total volume of 759,898 gallons, according to the report. Texas ranked first with 3.88 million gallons.
Methanol was the most widely used chemical. The substance is a hazardous air pollutant and is on the candidate list for potential regulation under the Safe Drinking Water Act.
Chemical 2-butoxyethanol, or 2-BE, was one of the most commonly used ingredients in hydraulic fracturing fluid. The report mentioned the U.S. Environmental Protection Agency found 2-BE in drinking water wells tested in Pavillion.
The report was issued by Reps. Henry Waxman of California, Edward Markey of Massachusetts and Diana DeGette of Colorado.
The chemicals are injected during hydraulic fracturing, a process used in combination with horizontal drilling to allow access to natural gas reserves previously considered uneconomical.
The growing use of hydraulic fracturing, or "fracking," has allowed natural gas production in the United States to reach levels not achieved since the early 1970s.
The process requires that large quantities of water and fluids are injected underground at high volumes and pressure. The composition of these fluids ranges from a simple mixture of water and sand to more complex mixtures with chemical additives.
The report said that from 2005-2009, the following states had at least 100,000 gallons of hydraulic fracturing fluids containing a carcinogen: Texas, Colorado, Oklahoma, Louisiana, Wyoming, North Dakota, New Mexico, Montana and Utah.
States with 100,000 gallons or more of fluids containing a regulated chemical under the Safe Drinking Water Act were: Texas, New Mexico, Colorado, Oklahoma, Mississippi and North Dakota.
The report said many chemical components were listed as "proprietary" or "trade secret." In a footnote, the report noted Wyoming's "robust" and "relatively strong" disclosure rules and said no state other than Arkansas had rules as stringent.
"Hydraulic fracturing has opened access to vast domestic reserves of natural gas that could provide an important stepping stone to a clean energy future," the report said.
"Yet, questions about the safety of hydraulic fracturing persist, which are compounded by the secrecy surrounding the chemicals used in hydraulic fracturing fluids. This analysis is the most comprehensive national assessment to date of the types and volumes of chemical used in the hydraulic fracturing process."
The "miniscule" amount of chemicals injected in wells is "nothing to get overly concerned about," said John Robitaille, vice president of the Petroleum Association of Wyoming, a group representing the state's oil and gas industries.
Since those chemicals are pumped deep underground below water supplies, it's the integrity of the cement casing around the well bore that protects water as the well plunges down through it, he said.
The state of Wyoming has specific rules for how that cement is to be applied and everything is regulated and tested, Robitaille said.
"That's really the thing that's been lost in this whole discussion," he said. "It's not so much what we put down the hole or where it goes. It's more the integrity of that well bore is such that nothing should go outside that pipe."
The investigation of chemicals used in fracking was started in the last Congress by the House Energy and Commerce Committee, which then was controlled by Democrats. The committee asked the 14 leading oil and gas service companies to disclose the types and volumes of the hydraulic fracturing products they used between 2005 and 2009 and the chemical contents of those products.