The U.S. Environmental Protection Agency is proposing the first-ever set of national standards to limit the harmful effects of the controversial gas drilling technique known as hydraulic fracturing, or fracking. The agency has been barred from regulating fracking since 2005, leaving oversight to state governments. Under the new proposal, the EPA would be able to limit emissions released during several stages of natural gas production and development. The EPA would also seek to reduce emissions of toxic chemicals, including cancer-causing benzene. A deadline to finalize the rules has been set for February 2012, but the country’s main oil and gas lobbying group, the American Petroleum Institute, is pushing for a six-month delay.