500 ppm  Sulfur NRLM  Credit
Calculation Guidance
Q:    The preamble and the regulations in the nonroad diesel rule describe differ-
ent methods for calculating how many 500 ppm sulfur NRLM credits may be gener-
ated at a refinery or import facility. In particular, the preamble says that ".. .refiners
and importers may obtain credit for early production/importation of fuel meeting
the 15 ppm sulfur standard and that they designate as NRLM from June 1, 2009
through May 31, 2010." However, 40 CFR 80.535(c) contains no requirement to
designate credit fuel as 15 ppm NRLM. Also, the credit generation equation in
80.535(c)(l)(iii) simply states that 500 ppm sulfur NRLM credits can be generated
for all 15 ppm diesel fuel produced or imported that is designated as either motor
vehicle diesel fuel or NRLM diesel fuel, in excess of a refinery or import facility's
baseline volume. Which method is correct?

A:    Refiners and importers should use the method specified in the regulations
at 40 CFR 80.535(c) to calculate how many 500 ppm sulfur NRLM credits they
may generate.  The baseline volume used to calculate credits generated equals the
annual average volume of all (15 ppm and 500 ppm) motor vehicle diesel fuel pro-
duced or imported from January 1, 2006 through December 31, 2008.  Thus, refiners
and importers must produce a volume of 15 ppm diesel equivalent to their baseline
volume as a first step toward generating 500 ppm sulfur NRLM credits. Refiners and
importers may then generate 500 ppm sulfur NRLM credits for any 15 ppm diesel fuel
produced in excess of a refinery's or import facility's baseline volume. The regula-
tions do not require refiners and importers to designate 15 ppm diesel fuel as NRLM
in order to generate 500 ppm sulfur NRLM credits.  However, refiners and importers
may not generate both motor vehicle diesel fuel credits and 500 ppm NRLM credits
for the same 15 ppm diesel fuel.
United States
Environmental Protection
Agency
                                    Office of Transportation and Air Quality
                                                       EPA-420-F-09-030
                                                             June 2009

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