An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Fuels Registration, Reporting, and Compliance Help

At what point in the distribution/receipt of ULSD will terminals need to sample/test for sulfur? If terminals do not test for sulfur content at the rack will they be able to assert an affirmative defense in the event that contaminated fuel is discovered a

Under the diesel sulfur program, there is no one time or physical location that a distributor must utilize for sampling. The party must use its knowledge of the distribution system, and information regarding each receipt of product (e.g., whether the shipment may include fuel that is very close to an interface with higher sulfur product) to determine when and where to sample.

However, as a general matter, we believe that a terminal should take samples during and/or after receipt of new product into the tank so that if there is a problem, it can be discovered and remedied before the product is distributed further downstream. If there is reason to believe that piping or a tank may contain high sulfur product then that may affect both sampling strategy and actions to prevent a potential violation.

This is but one example of many possible situations. In regards to terminals not testing for sulfur content at the rack, if a terminal does not conduct a sampling and testing program, it will likely be difficult to be able to establish a defense to presumptive liability.

Question and Answer was originally posted at Questions and Answers on the Clean Diesel Fuel Rules (PDF)(135 pp, 888 K, EPA420-B-06-010, July 2006, About PDF)