EPA will not consider the refiner's blending instructions to be compromised where the specified oxygenate contains de minimis amounts of other oxygenates resulting in the RFG produced to contain other oxygenates in amounts no more than: 0.4 vol% ethanol, or 0.6 vol% MTBE, ETBE, TAME or t-butanol, or 0.2 vol% methanol.
These exceptions apply only if the offending oxygenate is present as a result of operational necessity, and specifically would not apply if the offending oxygenate was intentionally added. See also the October 3, 1995 Question and Answer document, Prohibitions Section, Question 1, regarding the allowance of de minimis amounts other oxygenates in VOC-controlled RFG. (5/9/95)
This question and answer was posted at Consolidated List of Reformulated Gasoline and Anti-Dumping Questions and Answers: July 1, 1994 through November 10, 1997 (PDF)(333 pp, 18.17 MB, EPA420-R-03-009, July 2003, About PDF)