[Code of Federal Regulations]
[Title 40, Volume 2]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR51.35]

[Page 133]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 51--REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF 
IMPLEMENTATION PLANS--Table of Contents
 
          Subpart A--Emission Inventory Reporting Requirements
 
Sec. 51.35  How can my State equalize the effort for annual reporting?

    (a) Compiling a 3-year cycle inventory means much more effort every 
three years. As an option, your State may ease this workload spike by 
using the following approach:
    (1) Annually collect and report data for all Type A (large) point 
sources (This is required for all Type A point sources).
    (2) Annually collect data for one-third of your smaller point 
sources (Type B point sources minus Type A (large) point sources). 
Collect data for a different third of these sources each year so that 
data has been collected for all of the smaller point sources by the end 
of each three-year cycle. You may report these data to EPA annually, or 
as an option you may save three years of data and then report all of the 
smaller point sources on the three-year cycle due date.
    (3) Annually collect data for one-third of the area, nonroad mobile, 
onroad mobile and, if required, biogenic sources. You may report these 
data to EPA annually, or as an option you may save three years of data 
and then report all of these data on the three-year cycle due date.
    (b) For the sources described in paragraph (a) of this section, your 
State will therefore have data from three successive years at any given 
time, rather than from the single year in which it is compiled.
    (c) If your State chooses the method of inventorying one-third of 
your smaller point sources and 3-year cycle area, nonroad mobile, onroad 
mobile sources each year, your State must compile each year of the 
three-year period identically. For example, if a process hasn't changed 
for a source category or individual plant, your State must use the same 
emission factors to calculate emissions for each year of the three-year 
period. If your State has revised emission factors during the three 
years for a process that hasn't changed, resubmit previous year's data 
using the revised factor. If your State uses models to estimate 
emissions, you must make sure that the model is the same for all three 
years.
    (d) If your State chooses the method of inventorying one-third of 
your smaller point sources and 3-year cycle area, nonroad mobile, onroad 
mobile sources each year and reporting them on the 3-year cycle due 
date, the first required date for you to report on all such sources will 
be June 1, 2004 as specified in Sec. 51.25. You can satisfy the 2004 
reporting requirement by either: Starting to inventory one third of your 
sources in 2000; or doing a one-time complete 3-year cycle inventory for 
2002, then changing to the option of inventorying one third of your 
sources for subsequent years.
    (e) If your State needs a new reference year emission inventory for 
a selected pollutant, your State can't use these optional reporting 
frequencies for the new reference year.
    (f) If your State is a NOX SIP call State, you can't use 
these optional reporting frequencies for NOX SIP call 
reporting.