Marcellus driller volunteers to disclose fracking chemicals

The company that pioneered Marcellus Shale exploration announced Wednesday that it was voluntarily disclosing the chemicals used to hydraulically fracture its natural gas wells, in an effort to defuse criticism about the process.

Range Resources Corp., which has developed more Pennsylvania Marcellus wells than any other company since it drilled the first well in 2003, said it would provide a list of the chemical additives in an effort to demystify a technique the company says has been safely employed thousands of times.

"I'm confident, when people see the information, think about it, and understand it, our hope is that it will alleviate the concerns," said John Pinkerton, chief executive officer of the Fort Worth, Texas, firm.

Environmental groups and legislators, who have pressed for tighter regulation of the industry, welcomed Range's move.

"We need to see more details and the disclosure in action, but providing more information is a step in the right direction," U.S. Sen. Bob Casey (D., Pa.), a sponsor of the Fracturing Responsibility and Awareness of Chemicals (FRAC) Act, said through a spokesman. One of the FRAC Act's provisions is to require operators to disclose their chemical recipes.

Environmentalists said they were encouraged by the firm's step.

"Range is a big company, and now they've committed to this, it increases the pressure on other operators to follow," said Bruce Baizel, senior staff attorney with Earthworks' Oil & Gas Accountability Project.

Though the oil and gas industry has employed hydraulic fracturing for decades to stimulate well production, the process has come under close scrutiny recently as fossil-fuel exploration has moved into more "unconventional" geologic formations like shale and as well size has grown dramatically through the use of horizontal-drilling techniques.

In "fracking," millions of gallons of high-pressure water, sand, and chemicals are injected into a well to shatter the shale to release trapped natural gas. Sand particles remain in the hairline fractures to allow pathways for the gas to escape to the well. Some of the wastewater is recovered and recycled or treated and disposed of.

In the Marcellus, operators say that the fracturing occurs more than a mile below the surface and that the chemicals cannot migrate upward through thousands of feet of rock into aquifers.

But the industry's assurances have come under fire, and the process is being studied by the U.S. Environmental Protection Agency.