U.S. Environmental Protection Agency (EPA) has issued a draft guidance document to be used when "permitting the underground injection of oil- and gas-related hydraulic fracturing using diesel fuels where EPA is the permitting authority."  From the related press release:  "Today, the U.S. Environmental Protection Agency (EPA) released draft underground injection control (UIC) program permitting guidance for class II wells that use diesel fuels during hydraulic fracturing activities. EPA developed the draft guidance to clarify how companies can comply with a law passed by Congress in 2005, which exempted hydraulic fracturing operations from the requirement to obtain a UIC permit, except in cases where diesel fuel is used as a fracturing fluid."

Comments are due 60 days from its publication in the Federal Register.