The guidance is an interpretive memorandum intended to clarify the UIC requirements that apply to hydraulic fracturing using diesel and defines the term "diesel fuel" in a legal sense.

The guidance is also intended to help those issuing UIC permits but will not be cited as a basis for decision on the issuing of a permit.

The EPA says the clarification of the issuing of UIC permits for diesel can also be applied to best practices in hydraulic fracturing in general and will be available to states and tribes in the interest of protecting underground drinking water and public health.