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EPA Smooths Transition to Ultra-Low Sulfur Diesel Fuel

Release Date: 04/20/2006
Contact Information: John Millett, (202) 564-4355 /

(4/20/06) To help ensure a smooth transition to ultra-low sulfur diesel fuel (ULSD), EPA is temporarily adjusting the sulfur testing tolerance with a slightly wider range of variability in sulfur level test results. This minor change is necessary until more sensitive, more precise tests are in use throughout the fuel distribution system to reliably measure sulfur at very low levels. The tolerance will rise from 2 parts per million (ppm) to 3ppm through Oct. 14, 2008. This technical change will help ensure that fuel actually meeting the 15ppm sulfur cap is not falsely rejected and will not impact the sulfur cap taking effect June 1, 2006. The adjustment provides labs with more time to improve their measurement techniques, while strengthening the reproducibility of fuel sulfur tests based on current testing variability for some test methods. The final rule also amends the designate-and-track provisions to account for non-petroleum diesel fuels, such as biodiesel, and makes other minor clarifications.

Today's action has no adverse environmental impacts.

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