The Texas House gave tentative approval to a bill on Wednesday that would require gas companies to publicly disclose the chemicals they use in the controversial drilling process commonly known as "fracking."

State Rep. Jim Keffer, R-Eastland, the bill's sponsor, called it a "landmark piece of legislation" that would "establish a clear model for other states to follow."

The legislation would pertain to drillers engaged in hydraulic fracturing, a method that involves shooting a high-pressure concoction of water, sand and chemicals deep underground to extract gas from shale rock. It would require them to disclose the hazardous chemicals, and the amounts of those chemicals, on a public website run by the Oklahoma-based Groundwater Protection Council and the Interstate Oil and Gas Commission. (Those entities have set up a national public website already for companies to voluntarily disclose the chemicals, though Keffer's legislation would be mandatory for drillers operating in Texas.)

The Senate Natural Resources Committee will hear testimony on a bill on the same subject Thursday morning. The legislation is sponsored by State Sen. Jane Nelson, R-Nelson. The House bill also still must go through a final vote, expected during a "third reading" of the bill tomorrow.

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Hydraulic fracturing, or fracking, has stirred considerable concern among landowners near drilling sites, who worry about whether their aquifers can be contaminated. Keffer said: "Although there have been no cases of the [hydraulic fracturing] process causing groundwater contamination in Texas, the public has stated clearly that they want to know the chemicals used."

One driller, Range Resources, is in a standoff with the Environmental Protection Agency over the contamination of water wells in Parker County. The EPA has linked Range to the contamination, including in a court filing this week. Range denies contaminating the water, and the Railroad Commission has cleared the company.

The bill would allow companies to protect those chemical formulas that they feel are "trade secrets." Landowners in drilling areas could challenge such "trade secret" designation, with disputes ultimately going to the Texas Attorney General, Keffer said. State Rep. Tom Craddick, R-Midland, emphasized the need for sufficient trade secret protection.

An amendment offered by State Rep. Tan Parker, R-Flower Mound, would allow companies to keep secret the quantity of non-hazardous chemicals in their fracking fluid, even though they would need to disclose the chemicals themselves. The amendment was accepted.

Luke Metzger, the director of Environment Texas, called the bill a "first step" toward addressing concerns about fracking. "Texans have a right to know exactly what we’re being exposed to," he said in a statement.

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