Montana implements new rules requiring oil, natural gas companies to provide written, well-by-well disclosures of hydraulic fracturing chemicals to the state; officials say rules will increase public transparency

BILLINGS, Montana , September 15, 2011 () – Montana officials say new rules require energy companies to disclose the chemicals that are commonly pumped into oil and gas wells to increase production.

The Department of Natural Resources and Conservation said Thursday that the rules will increase public transparency for the industry.

The rules apply to the practice of hydraulic fracturing, or "fracking," in which a liquid mixture of chemicals is injected into a well to increase oil and gas production. The chemicals crack, or fracture, underground geological formations.

The practice has been blamed for polluting water supplies in parts of the country.

Companies have been reluctant to reveal the chemicals they use, characterizing them as trade secrets.

The new rules require oil and gas operators to provide written, well-by-well disclosures of those chemicals to the state.

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