The U.S. Environmental Protection Agency (EPA) released revised underground injection control (UIC) program permitting guidance for wells that use diesel fuels during hydraulic fracturing activities.

The EPA developed the guidance to help 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.

The EPA is issuing the guidance alongside an interpretive memorandum, which clarifies that class II UIC requirements apply to hydraulic fracturing activities using diesel fuels, and defines the statutory term diesel fuel by reference to five chemical abstract services registry numbers.

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For EPA permit writers, the guidance outlines existing class II requirements for diesel fuels used for hydraulic fracturing wells and technical recommendations for permitting those wells consistently with these requirements.

The EPA says decisions about permitting hydraulic fracturing operations that use diesel fuels will be made on a case-by-case basis, considering the facts and circumstances of the specific injection activity and applicable statutes, regulations and case law.

To read the EPA’s revised guidance, go here.