WASHINGTON (AP) — The Obama administration is proposing a rule that would require companies that drill for oil and natural gas on federal lands to publicly disclose chemicals used in hydraulic fracturing operations. The new "fracking" rule replaces a draft proposed last year that was withdrawn amid industry complaints that federal regulation could hinder an ongoing boom in natural gas production.

The rule proposed Thursday relies on an online database used by Colorado and 10 other states to track the chemicals used in fracking operations. FracFocus.org is a website formed by industry and intergovernmental groups in 2011 that allows users to gather well-specific data on thousands of sites.

Environmental groups and other critics say the site has loose reporting standards and allows companies to avoid disclosure by declaring certain chemicals trade secrets.