The NYT is reporting on U.S. EPA's efforts to regulate the use of diesel in hydraulic fracturing operations. "While Congress in 2005 exempted fracturing from the need to get permits under the Safe Drinking Water Act, it is not exempt when diesel is used. But companies have acknowledged using diesel in some instances. At a subcommittee hearing today, Sen. Tom Udall (D-N.M.) questioned Perciasepe on that."