Air Emissions Reporting Requirements, 76539-76558 [E8-29737]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 73, Number 243 (Wednesday, December 17, 2008)]
[Rules and Regulations]
[Pages 76539-76558]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-29737]


=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 51

[EPA-HQ-OAR-2004-0489; FRL-8749-5]
RIN 2060-AN20


Air Emissions Reporting Requirements

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This action finalizes changes to EPA's emission inventory 
reporting requirements. This action consolidates, reduces, and 
simplifies the current requirements; adds limited new requirements; 
provides additional flexibility to states in the ways they collect and 
report emissions data; and accelerates the reporting of emissions data 
to EPA by state and local agencies.

DATES: This final rule is effective on December 17, 2008.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. EPA-HQ-OAR-2004-0489. All documents in the docket are listed on the 
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy 
form. Publicly available docket materials are available either 
electronically through www.regulations.gov or in hard copy at the Air 
Emissions Reporting Requirements Docket, EPA/DC, EPA West Building, 
Room 3334, Constitution Ave., NW., Washington, DC. The Public Reading 
Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, 
excluding legal holidays. The telephone number for the Public Reading 
Room is (202) 566-1744, and the telephone number for the Air Docket is 
(202) 566-1742.

FOR FURTHER INFORMATION CONTACT: For general questions, please contact 
Dennis Beauregard, U.S. EPA, Office of Air Quality Planning and 
Standards, Air Quality Assessment Division, Mail Code C339-02, Research 
Triangle Park, North Carolina 27711; telephone number: (919) 541-5512; 
fax number: (919) 541-0684; e-mail address: beauregard.dennis@epa.gov. 
For legal questions, please contact Kristi Smith, U.S. EPA, Office of 
General Counsel, Mail Code 2344A, 1200 Pennsylvania Avenue, NW., 
Washington, DC 20460, telephone (202) 564-3068, e-mail at 
smith.kristi@epa.gov.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. General Information
    A. Does this action apply to me?
    B. Where can I get a copy of this document and other related 
information?
    C. Public Comments on Proposed Rule
    D. Judicial Review
II. Background and Purpose of This Rulemaking
III. Response to Comments
    A. Major Source Definition for Point Source Reporting
    B. Harmonizing Report Due Dates
    C. Accelerating Report Due Dates
    D. Reporting Biogenic Emissions
    E. Reporting Emission Model Inputs
    F. Reporting Summer Day Emissions
    G. Reporting Winter Work Weekday Emissions
    H. New Data Elements
    I. Identification of New Emissions Related Data Requirements
    J. Revisions to Specific Data Elements
IV. This Action
    A. Consolidation of Reporting Requirements
    B. Point Source Reporting
    C. Report Due Dates
    D. Reporting Biogenic Emissions
    E. Reporting Emission Model Inputs
    F. Reporting Summer Day Emissions
    G. Reporting Winter Work Weekday Emissions
    H. New Data Elements
I. Identification of New Emissions Related Data Requirements
    J. Revisions to Specific Data Elements
    K. EPA Initiated Changes
V. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution, or Use
    I. National Technology Transfer Advancement Act
    J. Executive Order 12898: Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations
    K. Congressional Review Act

I. General Information

A. Does this action apply to me?

    Categories and entities potentially regulated by this action 
include:

----------------------------------------------------------------------------------------------------------------
                                                   NAICS code
                    Category                          \a\                Examples of regulated entities
----------------------------------------------------------------------------------------------------------------
State/local/tribal government...................        92411  State, territorial, and local government air
                                                                quality management programs. Tribal governments
                                                                are not affected, unless they have sought and
                                                                obtained treatment as state status under the
                                                                Tribal Authority Rule and, on that basis, are
                                                                authorized to implement and enforce the Air
                                                                Emissions Reporting Requirements rule.
----------------------------------------------------------------------------------------------------------------
\a\ North American Industry Classification System.


[[Page 76540]]

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be regulated by this 
action.\1\ This action requires states to report their emissions to us. 
It is possible that some states will require facilities within their 
jurisdictions to report emissions to the states. To determine whether 
your facility will be regulated by this action, you should examine the 
applicability criteria in 40 CFR 51.1 of this rule. If you have any 
questions regarding the applicability of this action to a particular 
entity, consult the person listed in the preceding FOR FURTHER 
INFORMATION CONTACT section.
---------------------------------------------------------------------------

    \1\ As prescribed by the Tribal Authority Rule (63 FR 7253, Feb. 
12, 1998), codified at 40 CFR part 49, subpart A, tribes may elect 
to seek treatment as State (TAS) status and obtain approval to 
implement rules such as the AERR through a Tribal Implementation 
Plan (TIP), but tribes are under no obligation to do so. However, 
those tribes that have obtained TAS status are subject to the AERR 
to the extent allowed in their TIP. Accordingly, to the extent a 
tribal government has applied for and received TAS status for air 
quality control purposes and is subject to the AERR under its TIP, 
the use of the term State(s) in the AERR shall include that tribal 
government.
---------------------------------------------------------------------------

B. Where can I get a copy of this document and other related 
information?

    In addition to being available in the docket, an electronic copy of 
this final action will also be available on the worldwide Web (WWW) 
through the Technology Transfer Network (TTN). Following the 
Administrator's signature, a copy of the final amendments will be 
placed on the TTN's Clearing House for Inventories and Emission Factors 
(CHIEF) Web site at https://www.epa.gov/ttn/chief.

C. Public Comments on Proposed Rule

    The 120-day comment period for the proposed rule expired on May 3, 
2006. We received comments from 39 correspondents. These comments were 
submitted by 22 state and local agency representatives, 1 organization 
of state and local clean air agencies, 9 industries, 2 chambers of 
commerce and 5 commenters with no identified affiliation. While several 
comments were received days after the comment period ended, EPA did not 
treat these comments differently from comments received during the 
comment period. EPA has carefully considered all comments in developing 
the final amendments. Summaries of significant comments and EPA's 
responses are contained in this preamble. All comments are summarized 
and addressed in the document titled ``Response to Comments,'' which is 
available from the docket.

D. Judicial Review

    Under section 307(b)(1) of the Clean Air Act (CAA), judicial review 
of this final rule is available only by filing a petition for review in 
the United States Court of Appeals for the District of Columbia Circuit 
by February 17, 2009. Only those objections to this final rule that 
were raised with reasonable specificity during the period for public 
comment may be raised during judicial review. Under section 307(b)(2) 
of the CAA, the requirements that are the subject of this final rule 
may not be challenged later in civil or criminal proceedings brought by 
EPA to enforce these requirements.
    Section 307(d)(7)(B) of the CAA further provides a mechanism for us 
to convene a proceeding for reconsideration, ``[i]f the person raising 
an objection can demonstrate to the Administrator that it was 
impracticable to raise such objection within [the period for public 
comment] or if the grounds for such objection arose after the period 
for public comment (but within the time specified for judicial review) 
and if such objection is of central relevance to the outcome of the 
rule.'' Any person seeking to make such a demonstration to us should 
submit a Petition for Reconsideration to the Office of the 
Administrator, U.S. EPA, Room 3000, Ariel Rios Building, 1200 
Pennsylvania Ave., NW., Washington, DC 20460, with a copy to both the 
persons listed in the preceding FOR FURTHER INFORMATION CONTACT 
section, and the Associate General Counsel for the Air and Radiation 
Law Office, Office of General Counsel (Mail Code 2344A), U.S. EPA, 1200 
Pennsylvania Ave., NW., Washington, DC 20460.

II. Background and Purpose of This Rulemaking

    In today's action, EPA is amending the emission inventory reporting 
requirements in 40 CFR part 51, subpart A, and in 40 CFR 51.122. This 
action harmonizes reporting requirements under the NOX SIP 
Call and the Consolidated Emissions Reporting Rule (CERR). It also 
removes and simplifies some existing emissions reporting requirements 
which we believe are not necessary or appropriate; allows states to 
better track changes in source emissions, shutdowns, and startups over 
time by using the 40 CFR 70 definition of major source for point source 
reporting; deletes a requirement for states to report biogenic 
emissions; and offers states the option of reporting emission model 
inputs in lieu of reporting emissions for certain source categories. 
These changes were widely supported by states because they will 
simplify and reduce the states' reporting burden.
    In the preamble to the January 3, 2006, AERR proposed rulemaking 
(71 FR 69) we discussed state reporting requirements under the Clean 
Air Interstate Rule (CAIR) and included requirements for CAIR reporting 
in 40 CFR 51.123-51.125 under Subpart A. On July 11, 2008, the United 
States Court of Appeals for the District Court of Columbia Circuit 
vacated CAIR in its entirety. Accordingly, all references to CAIR and 
its reporting requirements have been removed from the final AERR. If 
CAIR (or some similar rule) becomes effective in the future, EPA will 
initiate a new rulemaking, as necessary, to address emission reporting 
requirements for that rule.
    Because we are consolidating, harmonizing and updating two pre-
existing sets of state emissions reporting requirements, we are 
reviewing the purpose, authority, and history of emissions reporting 
requirements in general.
    Emission inventories are critical for the efforts of state, local, 
and Federal agencies to attain and maintain the National Ambient Air 
Quality Standards (NAAQS) that EPA has established for criteria 
pollutants, such as ozone, particulate matter (PM) and carbon monoxide 
(CO). To assist these efforts, EPA initiated an effort in the early 
1990's to develop a central repository of inventory data for all states 
that is now known as the National Emission Inventory (NEI). Emission 
inventory data reported electronically under the CERR is stored in the 
NEI database and used by EPA and by states for air quality modeling, 
tracking progress in meeting CAA requirements, setting policy, and 
answering questions from the public. States often use the NEI as a 
starting point in developing emission inventories for support of State 
implementation plans (SIPs).
    Pursuant to its authority under sections 110 and 172 of the CAA, 
EPA has required SIPs to include inventories containing information 
regarding criteria pollutant emissions and their precursors (e.g., 
volatile organic compounds (VOC)). The EPA codified these inventory 
requirements in subpart Q of 40 CFR part 51 in 1979 and amended them in 
1987.
    The 1990 Amendments to the CAA revised many of the CAA provisions 
related to the attainment of the NAAQS and the protection of visibility 
in Class I areas. These revisions established new periodic emission 
inventory requirements applicable to certain areas that were designated 
nonattainment for

[[Page 76541]]

certain pollutants. For example, section 182(a)(3)(A) required states 
to submit an emission inventory every 3 years for ozone nonattainment 
areas beginning in 1993. Similarly, section 187(a)(5) required states 
to submit an inventory every 3 years for CO nonattainment areas. The 
EPA, however, did not immediately codify these statutory emission 
reporting requirements in the CFR, but simply relied on the statutory 
language to implement them.
    Title IV of the 1990 CAA Amendments also added requirements for 
reporting of emissions by sources subject to the Acid Rain Program 
(ARP). Affected sources must report hourly NOX, 
SOX and CO2 data to EPA's Clean Air Markets 
Division on a quarterly basis. Generally, these sources report annual 
NOX and SOX data aggregated from the hourly ARP 
data as well as other criteria and precursor pollutant emissions to 
states to satisfy reporting requirements for state permitting and 
emission inventory programs.
    In 1998, EPA promulgated the NOX SIP Call which required 
the affected states and the District of Columbia to submit SIP 
revisions providing nitrogen oxides (NOX) reductions to 
reduce their adverse impact on downwind ozone nonattainment areas. See 
63 FR 57356 (October 27, 1998). As part of that rule, codified in 40 
CFR 51.122, EPA established emissions reporting requirements to be 
included in the SIP revisions required under that action.
    Another set of emissions reporting requirements, the CERR, was 
promulgated by EPA in 2002, and is codified at 40 CFR part 51, subpart 
A. See 67 FR 39602 (June 10, 2002). These requirements replaced the 
requirements previously contained in subpart Q of 40 CFR part 51, 
expanding their geographic and pollutant coverages, while simplifying 
them in other ways.
    The principal statutory authority for the emission inventory 
reporting requirements outlined in this preamble is found in CAA 
section 110(a)(2)(F), which provides that SIPs must require ``as may be 
prescribed by the Administrator * * * (ii) periodic reports on the 
nature and amounts of emissions and emissions-related data from such 
sources.'' Section 301(a) of the CAA provides authority for EPA to 
promulgate regulations under this provision.\2\ At present, the 
emissions reporting requirements applicable to states are contained in 
two different locations: Subpart A of 40 CFR part 51 (the CERR) and 40 
CFR 51.122 in subpart G (the NOX SIP Call). This final rule 
will consolidate these requirements, with modifications as described 
below. The modifications are intended to harmonize, reduce, and 
simplify the emissions reporting requirements, and also make emissions 
reporting easier.
---------------------------------------------------------------------------

    \2\ Other CAA provisions relevant to these proposed amendments 
include section 172(c)(3) (requires SIPs for nonattainment areas to 
include comprehensive, current inventory of actual emissions, 
including periodic revisions); section 182(a)(3)(A) (requires 
emission inventories from ozone nonattainment areas); and section 
187(a)(5) (requires emission inventories from CO nonattainment 
areas).
---------------------------------------------------------------------------

    Under the NOX SIP Call requirements in 40 CFR 51.122, 
NOX emissions for a defined 5-month ozone season (May 1 
through September 30) from sources that the state has subjected to 
emissions control to comply with the NOX SIP Call are 
required to be reported by the affected states to EPA every year. 
However, NOX emissions from sources reporting directly to 
EPA as part of the NOX trading program are not required to 
be reported by the states to EPA every year. The affected states are 
also required to report ozone season emissions and typical summer work 
weekday emissions of NOX from all sources every third year 
(2002, 2005, 2008, etc.). This triennial reporting process does not 
have an exemption for sources participating in the NOX SIP 
Call emissions trading program. Section 51.122 requires that a number 
of data elements be reported in addition to ozone season NOX 
emissions. These data elements describe some of the source's specific 
physical and operational parameters.
    Emissions reporting under the NOX SIP Call (promulgated 
October 27, 1998) was required for the 2002 inventory year which was 
the year prior to the emissions reductions requirement. The reports are 
due to EPA on December 31 of the year following the inventory year. For 
example, emissions from all sources and types in the 2002 ozone season 
were required to be reported on December 31, 2003. However, because the 
Court which heard challenges to the NOX SIP Call delayed the 
implementation by one year to 2004, see Michigan v. EPA, 213 F.3d 663 
(D.C. Cir. 2000), cert. denied, 121 S. Ct. 1225, 149 L. ED. 135 (2001), 
no state was required to start reporting until the 2003 inventory year. 
In addition, EPA subsequently promulgated a rule to subject Georgia and 
Missouri to the NOX SIP Call with an implementation date of 
2007. See 69 FR 21604 (April 21, 2004). For these states, emissions 
reporting began with 2006. The emissions reporting requirements under 
the NOX SIP Call presently affect the District of Columbia 
and 20 states.
    As noted above, the other set of emissions reporting requirements 
is codified at subpart A of part 51. Although entitled the 
``Consolidated Emissions Reporting Rule,'' the CERR left in place 
separate reporting requirements for the NOX SIP Call under 
40 CFR 51.122. The CERR requirements were aimed at obtaining emissions 
information to support a broader set of purposes under the CAA than 
were the reporting requirements under the NOX SIP Call. The 
CERR requirements apply to all states and include the reporting of all 
criteria pollutants and criteria pollutant precursors.
    The CERR and the NOX SIP Call both require states to 
report emissions of all sources at 3-year intervals (inventory years 
2002, 2005, 2008, etc.). However, there are a number of differences 
between the two rules. The CERR also requires reporting of certain 
large sources every year, and the required reporting date under the 
CERR is 5 months later than under the NOX SIP Call reporting 
requirements. Also under the CERR, emissions must be reported by all 
states as a total for the entire inventory year, for a typical work 
weekday in winter, and for a typical work weekday in summer, but not a 
total for the 5-month ozone season as is required by the NOX 
SIP Call. The NOX SIP Call requires a special all-sources 
report by affected states for the year 2007 due December 31, 2008.\3\ 
Finally, the CERR and the NOX SIP Call differ in what non-
emissions data elements must be reported.
---------------------------------------------------------------------------

    \3\ It is important to note that the NOX SIP Call 
requires a special all-sources report by affected States for the 
2007 inventory year due December 31, 2008. While the CAIR had 
removed the requirement to submit the special all-sources report, 
the recent vacatur of CAIR in its entirety means that the special 
all-sources report is once again a requirement under the 
NOX SIP Call.
---------------------------------------------------------------------------

III. Response to Comments

    We have addressed all comments in detail and placed them in the 
Response to Comments document in the docket. The comments that concern 
significant proposed changes have been summarized and addressed, as 
discussed below. As an aid to the reader, we have grouped related 
comments under headings that generally correspond to the organization 
of the proposed rulemaking.

A. Major Source Definition for Point Source Reporting

    In all states, we proposed to expand the definition of sources that 
must be reported in the point source format,

[[Page 76542]]

resulting in fewer sources included in the nonpoint source formats.\4\ 
We proposed to base the requirement for point source format reporting 
on whether the source is a major source under 40 CFR part 70 for the 
pollutants for which reporting is required, i.e., for CO, VOC, 
NOX, sulfur dioxide (SO2), PM2.5, 
PM10, lead and ammonia (NH3). Those major sources 
were further classified as Type A (large sources) and Type B (small 
sources), with differing reporting requirements for each type. 
Currently, the requirement for point source reporting is based on 
thresholds of actual emissions during the inventory year. While it has 
always been an option for states to include all such sources, and we 
know that some states already do, expanding the point source definition 
may require more sources to be reported as point sources every third 
year. Affected states would continue to report their actual emissions, 
but the new approach would make it possible to better track changes in 
source emissions, shutdowns, and start-ups over time. Because states 
have existing lists of sources subject to 40 CFR part 70 requirements, 
this approach would result in a more stable universe of reporting point 
sources, which in turn would facilitate elimination of overlaps and 
gaps in estimating point source emissions, as compared to nonpoint 
source emissions. Under this proposal, states would know well in 
advance of the start of the inventory year which sources would need to 
be reported. We proposed that these new requirements begin with the 
2008 inventory year.
---------------------------------------------------------------------------

    \4\ We use the term ``nonpoint source'' to refer to a stationary 
source that is treated for inventory purposes as part of an 
aggregated source category rather than as an individual facility. In 
the existing subpart A of part 51, such emissions sources are 
referred to as ``area sources.'' However, the term ``area source'' 
is used in section 112 of the CAA to indicate a nonmajor source of 
hazardous air pollutants, which could or could not be a point 
source. As emission inventory activities increasingly encompass both 
NAAQS-related pollutants and hazardous air pollutants, the differing 
uses of ``area source'' can cause confusion. Accordingly, EPA is 
substituting the term ``nonpoint source'' for the term ``area 
source'' in subpart A and in subpart G (Sec.  51.122 to avoid 
confusion.
---------------------------------------------------------------------------

    We received a number of comments on the provision regarding point 
source format reporting. All commenters supported changing the 
definition of a point source for reporting purposes to that used in 40 
CFR part 70. Therefore, EPA intends to implement this reporting change 
but with certain caveats prompted by other comments, as discussed 
below.
    One commenter thought that the table included in the definition for 
point source in the proposed rule was inconsistent with the proposed 
reporting requirements using the Title V definition. The commenter 
noted that the definition for ``type A source'' seemed inconsistent 
with the proposed change from actual emissions to ``potential to 
emit.''
    The EPA agrees with the commenter that there were some 
inconsistencies in the proposed rule. The preamble for the proposed 
rule stated that EPA is ``proposing to base the requirement for point 
source format reporting on whether the source is a major source under 
40 CFR part 70 for the pollutants for which reporting is required * * 
*.'' This indicated that reporting thresholds for all point sources 
would be based upon the 40 CFR part 70 definition of ``potential to 
emit'' (PTE). However, we further stated that ``we are proposing to 
expand the definition of what sources must be reported in point source 
format so that fewer sources would be included in nonpoint source 
emissions.'' Later in the preamble, we stated that ``this change may 
require more sources to be reported as point sources every third 
year.'' Both sentences imply that the change would apply only to Type B 
sources. Application of the 40 CFR part 70 point source definition to 
all point sources would likely require some existing Type B point 
sources to be reported each year as Type A sources, which was not 
identified as a likely change in point source reporting.
    The EPA used the definition for point source to establish that use 
of the 40 CFR part 70 major source definition would begin with the 2008 
inventory year. Point source reporting for years prior to 2008 would 
continue to be based upon use of ``actual emissions.'' However, the 
point source definition includes a table for reporting Type A and B 
sources, and that table indicates that the reporting thresholds in the 
table are ``in tons per year of actual emissions.'' While EPA intended 
that the emissions reported would continue to be actual emissions, PTE 
was to be used to determine point source reporting requirements, and no 
consideration of this change is included in the table.
    The proposed definition for Type A sources required use of ``actual 
annual emissions'' to determine reporting requirements. However, the 
use of actual annual emissions to determine Type A sources appears to 
conflict with the point source definition (applicable to both Type A 
and B point sources), which indicated that emission reporting for 2008 
and later years would be determined using the 40 CFR part 70 definition 
of ``major source,'' which uses PTE.
    Given the confusing preamble language and apparent conflict in the 
text of the regulation, EPA will accept use of either approach to 
determine Type A point source reporting requirements for the 2009 
inventory year. For the inventory years following 2009, EPA will expect 
states to use the 40 CFR part 70 major source definition for all point 
sources to simplify reporting requirements, as discussed in the 
proposal preamble. Accordingly, EPA has revised the definition of Type 
A sources and Table 1 in Appendix A to subpart A to make clear that the 
40 CFR part 70 definition of major source will be used to determine 
point source reporting requirements following the 2009 inventory year.

B. Harmonizing Report Due Dates

    The CERR reporting dates are 5 months later than the NOX 
SIP Call. The NOX SIP Call rule requires the affected states 
to submit emission inventory reports for a given ozone season to EPA by 
December 31 of the following year, 12 months after the end of the 
inventory year. The CERR requires similar but not identical reports 
from all states by the following May 31, 17 months after the end of the 
inventory year. The EPA believes that harmonizing these reporting dates 
would be efficient for both states and EPA.
    The EPA proposed to shorten the timeline of 17 months for reporting 
under the CERR to be consistent with the 12 months for reporting under 
the NOX SIP Call. A second alternative requiring 12 months 
for reporting of point sources and 17 months for nonpoint and mobile 
sources was also proposed.
    Most commenters expressed support for the concept of harmonizing 
the reporting requirements under the NOX SIP Call and the 
CERR, but were concerned about the alternative of using the 12-month 
timeline for some or all sources for the 2008 inventory year. In 
general, the commenters were concerned that a 12-month timeline might 
compromise the quality of the data and urged EPA to harmonize the 
report due date at 17 months for all emission sectors (point, nonpoint, 
and mobile).
    The EPA agrees with the concerns of the commenters regarding the 
proposal to tighten the timeline to 12 months for the 2008 inventory 
year, and accordingly, has decided to delay implementing the AERR and 
the 12-month timeline for reporting of all emission sectors until 2009. 
Since the 2009 and 2010 inventory years require reporting for Type A 
(large point) sources only, one impact of this action

[[Page 76543]]

is to delay implementing a 12-month timeline for reporting of all 
sources until the 2011 inventory year, which is the next 3-year 
comprehensive emission inventory year. For the 2008 inventory year, 
retaining the existing 17-month timeline under the CERR will provide 
additional stability for states using the new data submittal and 
operating procedures for the Emission Inventory System (EIS), which 
will be operational for the 2008 inventory year. The 17-month timeline 
will allow state agencies to adapt to the new data reporting and system 
requirements without introducing additional constraints and uncertainty 
to the process. It will also provide a complete inventory cycle for EPA 
to correct any problems with the new system procedures.
    The EPA notes that although some commenters supported a 17-month 
timeline for reporting of all source emissions for the 2008 inventory 
year, we did not propose to extend the existing 12-month timeline for 
reporting under the NOX SIP Call. Thus, the NOX 
SIP Call 12-month timeline will be retained for the 2008 inventory 
year, and harmonized reporting under the AERR will be implemented for 
the 2009 inventory year.

C. Accelerating Report Due Dates

    The EPA believes that the public is best served by making 
environmental information available as soon as possible. Therefore, we 
proposed that the reporting schedule be further accelerated for the 
triennial year 2011 and all following years by requiring that emissions 
data from all point sources be reported within 6 months from the end of 
the inventory year, i.e., by June 30 of the following year. Under the 
proposed rule, reporting on all other sources would be required within 
12 months, i.e., by December 31 of the following year. There is 
precedent for requiring reporting of point source emissions data within 
6 months. For example, beginning with the year 1979, states were 
required, under subpart Q, to report point source emissions data within 
6 months. We invited comment on alternative reporting schedules of 6 to 
12 months for point sources and 12 to 17 months for all other sources.
    Most commenters were concerned with the proposed 6-month timeline 
for states to submit point source data for the 2011 inventory year. The 
commenters generally indicated that the accelerated schedule would 
create a very short timeframe for point sources to gather the emissions 
data needed to report to states and for states to process and quality 
assure the data, resulting in incomplete and inconsistent data quality. 
Several commenters thought that tightening the timeline for point 
sources to 9 to 12 months would be possible. Some of the commenters 
thought that 17 months would continue to be needed for the nonpoint and 
mobile source inventory sectors due to the unavailability of data on a 
shorter schedule from other agencies needed to develop the emission 
estimates.
    Two commenters wanted to retain the existing 17-month timeline for 
reporting point, nonpoint, and mobile source data. One of the 
commenters expressed concerns that were based primarily on having to 
conduct a similar data collection and compilation effort within 
California. The commenter thought that the time to conduct this state-
based effort made accelerating the Federal emissions reporting timeline 
to less than 17 months unrealistic and could compromise data quality. 
The other commenter expressed opposition to the concept of a bifurcated 
reporting system which would require submittal of point and nonpoint/
mobile source sector data on separate dates.
    Two commenters thought that Web-based submittal tools needed to 
move beyond the developmental stage before it would be possible to 
shorten the reporting timeframe to 12 months. One of the two commenters 
further indicated that much of the activity data needed to develop the 
nonpoint source estimates are not available until 12 to 15 months after 
the inventory year and thought EPA should consider using previous year 
data as a surrogate for the current year.
    The EPA agrees with the concerns expressed by most of the 
commenters regarding the proposed 6-month timeline for submittal of 
point source data by the 2011 inventory year. When EPA developed the 
proposed rulemaking, a project known as the ``Rapid Inventory 
Development Pilot'' was initiated. The EPA has now evaluated the 
results of the project and believes that a 6-month timeline for 
developing and submitting inventory data is not yet achievable on a 
consistent basis with application of proper quality assurance 
procedures for all emission inventory source sectors. However, the 
project did demonstrate that a timeline shorter than the existing 17 
months is possible, since a number of states involved in the project 
were able to submit data to EPA 10 months after the emission inventory 
year.
    The EPA understands that some difficulties were encountered by 
several of the states participating in the project, which indicates 
that additional time is needed to refine both the electronic tools and 
the procedures to support, on a consistent basis, development and 
submittal of emissions data on an expedited timeline. To allow 
additional time for technological improvements, EPA will implement a 
12-month timeline for data submittals beginning with the 2009 inventory 
year. The effect of this will be to require reporting of Type A (large 
point) sources using a 12-month timeline for the 2 years before the 
comprehensive triennial emission inventory effort for the 2011 
inventory year. This will allow for additional development of 
electronic tools and refinement of data submittal procedures and for 
states to become familiar with operation of the new EIS before the 2011 
triennial inventory is due.

D. Reporting Biogenic Emissions

    We proposed to remove a requirement in the existing CERR for states 
to report annual and typical ozone season day biogenic emissions. 
Biogenic emissions are estimated by a computer model using 
meteorological and land use/land cover data as inputs. Because EPA can 
develop these data inputs directly without having them reported by 
state, local, and tribal agencies, we believe the requirement for 
reporting biogenic emissions serves no useful purpose. This change does 
not affect our expectation that biogenic emissions be appropriately 
considered in ozone and PM2.5 attainment demonstrations.
    Many comments were submitted on the biogenic emissions reporting 
requirement, and all supported EPA's proposal to not include biogenic 
emissions reporting in the AERR. Based upon the support expressed by 
the commenters, EPA will implement this part of the AERR as proposed by 
not including the existing reporting requirements (under the CERR) for 
annual and typical ozone season day biogenic emissions.

E. Reporting Emission Model Inputs

    We proposed a new provision that would allow states the option of 
providing emission inventory estimation model inputs in lieu of the 
actual emissions estimates developed from those inputs. This provision 
was limited to source categories for which, prior to the report due 
date, EPA developed or adopted emissions estimation models and through 
guidance defined their necessary inputs. This provision would allow 
states to take advantage of new emissions estimation tools for greater 
efficiency, although the states would continue to be required to 
provide inputs representative of their conditions. Under this option, 
EPA will run the emissions model(s) to calculate

[[Page 76544]]

emissions and will enter the emissions data into the appropriate 
database. Section 51.15(d) limited this option to ``* * * models 
capable of estimating emissions from a certain source type on a 
national scale * * *.'' and thus restricted its application to nonpoint 
and mobile source emission categories. We proposed that this option 
would be available starting with the reports on 2005 emissions. 
Furthermore, we invited comment on requiring states to provide model 
inputs for source categories for which they have utilized a widely 
available emissions model as a means of improving the transparency of 
the emission estimates themselves and the overall utility of the 
submissions in meeting the objectives of the emissions reporting 
requirements. Providing model inputs would improve EPA's ability to 
assess the quality of the states' emission estimates and to project 
future emissions.
    We received several comments on this provision. Most of the 
comments were in favor of allowing the option to report model inputs in 
lieu of the emissions estimated from the models. However, many of the 
commenters did not want to see the reporting of model inputs become a 
reporting requirement.
    The EPA agrees with the majority of commenters who supported the 
option of submitting input data in lieu of emission estimates and will 
make this an option. Although the proposed rule indicated this option 
would be available for reporting emissions for the 2005 inventory year, 
EPA intends to delay implementation of this option until the 2007 
inventory year (due date May 31, 2009) since this rule was not 
published before the due date for data from the 2005 inventory year 
(May 31, 2007). Although EPA encourages states to submit model inputs 
where they have used a widely available model to develop emission 
estimates, states will not be required to submit input data when they 
provide emission estimates.
    The EPA notes that emissions data based upon physical measurements 
are generally preferred over estimates developed using models or 
emission factors, but the Agency believes that models and emission 
factors are appropriate emission estimation tools when addressing the 
ubiquitous nature of some sources and attempting to account for the 
many variables affecting certain annual emission estimates. To improve 
the application of models and emission factors, EPA urges states to 
develop locally derived input data based upon physical measurements 
wherever possible.

F. Reporting Summer Day Emissions

    We proposed to retain the requirement for reporting of summer day 
emissions from all sources (except biogenic sources) at three-year 
intervals, but to restrict the requirement to only those states with 
ozone nonattainment areas or states covered by the NOX SIP 
Call. We proposed to restrict the requirement to VOC and NOX 
emissions, but we invited comment on whether CO emissions should be 
required also.
    Several commenters supported EPA's proposal for reporting of summer 
day emissions of NOX and VOC. Two commenters thought that 
ozone season-day NOX, VOC and CO emissions should be 
reported for all areas, while two other commenters questioned the value 
of reporting summer day VOC and NOX emissions. Another 
commenter thought that requiring ozone season and daily emissions for 
point, nonpoint, and nonroad sources was redundant since the temporal 
parameters needed to calculate these emissions were required to be 
reported.
    One commenter thought that summer day emissions of CO should not be 
reported, while two other commenters believed that reporting CO summer 
day emissions was necessary but only for CO nonattainment areas.
    The EPA agrees with the majority of the commenters that the 
reporting requirements for summer day emissions (VOC and 
NOX) from all sources (except biogenic sources) at 3-year 
intervals should only include states with ozone nonattainment areas and 
states covered by the NOX SIP Call. However, EPA believes 
that it is appropriate to also include summer day emissions reporting 
for sources in attainment counties that are covered by the 
nonattainment area modeling domain used to demonstrate reasonable 
further progress (RFP). The EPA's current guidance requires RFP 
calculations to be done on an ``average summer weekday emissions'' 
basis. If the state takes credit for reductions from outside the 
nonattainment area, the requirement will be to determine whether there 
were reductions in average summer weekday emissions from those sources.
    The EPA believes that reporting of CO summer day emissions is not 
necessary since, as noted by one commenter, other data elements already 
reported allow summer day emissions to be derived and CO emissions, 
unlike VOC and NOX emissions, are not used for tracking RFP. 
Therefore, reporting of CO summer day emissions regardless of ozone 
attainment status will not be a requirement under the AERR.
    The proposed rule indicated that ``We are proposing to retain the 
requirement for reporting of summer day emissions * * *.'' However, the 
CERR actually requires reporting of ``work weekday emissions.'' for 
point sources and ``summer work weekday emissions'' for nonpoint and 
mobile sources. Although we did not receive comments on the work 
weekday versus summer day emissions issue, we realize that the preamble 
language indicated that no changes would be made to the summer day 
emissions definition contained in the CERR (beyond the proposal to 
restrict the requirement to ozone nonattainment and NOX SIP 
Call areas), but the proposed AERR regulatory language made additional 
changes to the definition of ``summer day emissions'' since the CERR 
required ``work weekday emissions'' for point sources and ``summer work 
weekday emissions'' for nonpoint, nonroad mobile and onroad mobile 
sources.
    Accordingly, in recognition of the conflicting language and as 
indicated in the preamble to the proposed rule, the final rule will 
retain the definition of and requirement to report ``summer day 
emissions'' for all sources revised only to the extent that it will 
restrict the requirement to ozone nonattainment areas (including 
sources in counties that are covered by the modeling domain used to 
demonstrate RFP) and NOX SIP Call areas. In addition, the 
definition for summer day emissions has been revised to require the use 
of work weekday emissions (as required under the CERR) when estimating 
summer day emissions for reporting.

G. Reporting Winter Work Weekday Emissions

    We proposed to delete the existing requirement that all states 
report emissions for a winter work weekday. This requirement was 
originally aimed at tracking progress towards attainment of the CO 
NAAQS. We stated our belief that applying this requirement to all 
states was no longer warranted given that CO violations are currently 
observed in few areas and indicated that we would work directly with 
the few remaining affected states to monitor efforts to attain the CO 
NAAQS without requiring formal submission of CO inventories.
    Most commenters supported EPA's proposal to delete the reporting 
requirement for winter work weekday emissions of CO. However, one 
commenter opposed EPA's proposal to eliminate the existing reporting 
requirement. The commenter thought that the requirement should be 
retained for states that are required to submit

[[Page 76545]]

emission inventory data as part of their CO maintenance plans.
    The EPA finds the comment that CO reporting is needed for CO 
maintenance plans to be compelling. This need was not considered in the 
proposed rule. As noted by the commenter, CO maintenance plans require 
tracking of emission reductions to ensure continued maintenance of the 
CO NAAQS. Reporting emissions under this rule will aid in standardizing 
the data reported and facilitate review of the data by interested 
parties.
    A concern not raised by commenters but brought to EPA's attention 
since the proposed rule was published relates to requests from states 
to discontinue monitoring of ambient CO concentrations in certain areas 
that have been redesignated to attainment for CO. The EPA's approval of 
such requests is conditioned on the expectation that emissions will not 
increase and areas will continue to maintain the CO NAAQS. To provide a 
means of ensuring that the CO NAAQS are maintained in areas that no 
longer have ambient CO monitors, emissions reporting becomes even more 
critical.
    The proposed rule indicated that EPA could work on a case-by-case 
basis with the few remaining CO nonattainmment areas regarding 
reporting of winter work weekday emissions. However, in this final 
rule, EPA has determined that for those areas in which EPA determines 
that reporting is still needed, reporting emissions under this rule 
will ensure that CO emissions are reported periodically and that the 
data are in a standardized format that will facilitate data review and 
thus help ensure attainment and maintenance of the CO NAAQS. Therefore, 
to monitor progress toward attaining and maintaining the CO NAAQS, EPA 
will retain the requirement for reporting winter work weekday emissions 
of CO, but will limit it to CO nonattainment areas and areas with CO 
maintenance plans.

H. New Data Elements

    We proposed to add several required data elements to the existing 
rule. These were contact name, contact phone number, emission release 
point type, control status, emission type, and method accuracy 
description (MAD) codes.
    The contact name and phone number are for the lead contact in the 
organization submitting the data and are needed to ensure that EPA 
knows who to contact if issues arise with a data submission.
    The emission release point type is a code for the physical 
configuration of the emission release point (e.g., vertical stack, 
fugitive, etc.). It is needed to correctly model how emissions are 
released into the atmosphere.
    The control status is a code that represents whether reported 
emissions are controlled or uncontrolled. It is needed to project 
future emissions correctly and to evaluate the impact of emission 
control programs correctly. We also invited comment on whether, with 
this addition, the current data elements that describe emissions 
control equipment type and efficiency were adequate. We indicated our 
belief that it is important for states to report on the manner in which 
emissions from sources are currently controlled so that opportunities 
for control strategy and regulatory development could be assessed. We 
questioned whether the existing data elements were adequate and 
appropriate for that purpose. The existing data elements related to 
control measures are primary control efficiency, secondary control 
efficiency, control device type, and rule effectiveness for point 
sources; and total capture/control efficiency, rule effectiveness, and 
rule penetration for nonpoint sources and nonroad mobile sources.\5\
---------------------------------------------------------------------------

    \5\ Additional information on emissions data elements and the 
formats and valid codes presently in use for State reporting to EPA 
is available on the EPA Web site https://www.epa.gov/ttn/chief/nif/
index.html.
---------------------------------------------------------------------------

    The emission type is a code describing the temporal period of 
emissions reported (e.g., annual, day, etc.). It is needed to ensure 
that emissions estimates are used properly.
    The MAD codes provide information about geographic coordinates, 
including the collection method, accuracy, and other descriptors. We 
proposed to add MAD codes to this rule because EPA's Latitude/Longitude 
Data Standard \6\ requires their collection when latitude and longitude 
are collected. The MAD codes are horizontal collection method code, 
horizontal accuracy measure, horizontal reference datum code, reference 
point code, source map scale number, and coordinate data source code. 
The EPA believed that many states would be able to report these codes 
based on existing information. However, in the event that the 
information needed to report these codes was not available, states 
would not be required to do additional work since there is a ``don't 
know'' code.
---------------------------------------------------------------------------

    \6\ Environmental Data Registry: Latitude/Longitude Standard. 
2000. U.S. EPA. December 11, 2000. https://oaspub.epa.gov/edr/edr_
proc_qry.navigate?P_LIST_OPTION_CD=CSDIS&P--REG--AUTH--
IDENTIFIER=1&P--DATA--IDENTIFIER=19939&P--VERSION=2.
---------------------------------------------------------------------------

    While several commenters supported EPA's proposal to add new data 
elements to this rule, a number of other commenters appeared to be 
confused by EPA's proposal since the NEI Input Format (NIF) included 
many of the new data elements, and they were already reporting the data 
to EPA. These commenters believed that adding the new data elements to 
this rule was not necessary and that the proper place for such detailed 
information was in the NIF data reporting format or in guidance 
documents. Two commenters in this group suggested that a Federal-state 
task force be established to review, revise, finalize, and implement 
changes in code details.
    The EPA believes that both data reporting rules and data reporting 
formats, such as the NIF, are needed for effective data reporting. 
Although this rule and NIF address many common data elements for 
reporting to EPA, their purposes are somewhat different. Data reporting 
rules identify data elements and timelines for reporting. Data 
reporting formats such as the NIF address the details of how the data 
are to be reported to facilitate handling of the data by EPA.
    The EPA does not believe that using a data formatting protocol such 
as the NIF is an effective way to communicate data needs with state 
agencies. The EPA has codified data reporting requirements since states 
need to understand what data will be required and when it will be 
required by EPA to implement programs under the Clean Air Act. The EPA 
continues to believe that data elements for reporting and timelines for 
submitting data are fundamental requirements for states and therefore 
are appropriate levels of detail to be addressed through the rulemaking 
process.
    One commenter suggested that a Federal-state task force be 
established to review, revise, finalize, and implement changes in code 
details. Such a task force has since been established to help with 
developing the new EIS. The EPA expects the task force to update tools 
and guidance materials for data reporting, as well as periodically 
review data elements and reporting codes for use by state agencies.
    Two commenters thought that the addition of a control status code 
would not make the status of a facility any more clear and believed 
that the control status of a facility could be determined from other 
data elements already required for reporting under the CERR and 
proposed under the AERR (e.g., control device codes and control 
efficiency).
    One of the commenters pointed out that EPA's detailed reporting 
instructions provide for the ``control device'' data element to specify

[[Page 76546]]

nonphysical equipment control techniques such as ``low solvent 
coatings,'' ``water-borne coatings,'' ``process change,'' and several 
varieties of combustion modifications.
    The EPA notes that ``control status'' was the only new data element 
in the proposal that was not already in the NIF Version 3.0 and thus 
was perceived as a new data reporting requirement by several 
commenters. This new data element would require states to indicate if a 
source is controlled or uncontrolled. The EPA agrees with the concerns 
expressed by the commenters that this new data element is not needed. 
The data reporting requirements proposed under this action for control 
types and efficiencies in combination with reporting codes for those 
data elements will be sufficient to discern whether or not sources are 
uncontrolled or controlled and to what extent. Therefore, EPA has 
decided to not include Control Status as a new data element in this 
action.
    One commenter stated that the current data fields for point sources 
do not ask for the total capture/control efficiency, which is required 
for nonpoint sources. The commenter thought that the capture efficiency 
along with the total capture/control efficiency should be required for 
point sources since the current requirements for primary and secondary 
control efficiencies do not provide a way to determine the overall 
control efficiency. The EPA believes that the ``total capture and 
control efficiency'' data element proposed for point source reporting 
addresses the commenter's concern since this data element is intended 
to require data reporting on the overall effects of multiple control 
systems.
    One commenter did not believe that ``Rule Effectiveness'' had ever 
been explained adequately and stated that it was not apparent how or if 
it could be used without knowledge of how it relates to the other 
terms. The EPA disagrees with the commenter's concerns. In the spring 
of 2004, EPA convened a workgroup consisting of emission inventory 
staff from state, local, and EPA offices to review existing rule 
effectiveness (RE) guidance and develop a consensus recommendation for 
improvements to this guidance. The revised RE guidance developed by the 
workgroup is found in Appendix B of the document titled Emissions 
Inventory Guidance for Implementation of Ozone and Particulate Matter 
National Ambient Air Quality Standards (NAAQS) and Regional Haze 
Regulations--EPA-454/R-05-001 (August 2005, updated November 2005). The 
EPA believes the workgroup presented a clear rationale regarding 
development and implementation of the new approach to adjusting 
emission inventories to address RE, explaining how RE can be used to 
adjust the control efficiency, from what could be realized under ideal 
conditions to what is actually emitted in practice due to less than 
ideal conditions. Accordingly, EPA has expanded the regulatory 
definition of RE to explain how it is used in making these adjustments.
    Several commenters were generally opposed to any additional 
reporting requirements for states that would be passed on to businesses 
but offered no specific concerns with the individual requirements. The 
reporting requirements of this rule will apply to states and not to 
sources. However, we recognize that in some cases, states will need to 
modify their data reporting rules to meet the requirements of this rule 
for data elements to be reported and the new timelines for reporting. 
The EPA notes that the burden estimate from the proposed rule's 
Supporting Statement for the Information Collection Request (ICR) 
indicates the AERR will not increase the reporting burden on states or 
impose an additional burden on sources.

I. Identification of New Emissions Related Data Requirements

    We invited comment on whether or not additional emissions related 
data should be required. Several commenters encouraged EPA to include 
specific requirements in this rule for reporting hazardous air 
pollutants (HAPs) emissions data for Title V facilities. One commenter 
encouraged EPA to include requirements for reporting HAPs from all 
emission sources.
    The EPA is not including requirements for reporting HAPs in this 
rule. However, EPA has developed national level inventories of HAP 
emissions on a 3-year cycle since 1990. These inventories have provided 
support for development of HAP control programs, helped assess HAP air 
quality trends, and provided a means to track EPA's progress on 
controlling HAP emissions under the Government Performance Results Act. 
The success of EPA's efforts rests in large measure on the cooperation 
of states in submitting HAP data to EPA to support the development of 
national HAP emission inventories. Each emission inventory cycle has 
benefited from increased state agency participation in submitting HAP 
data. The EPA believes it will be possible to continue developing and 
improving national level HAP inventories using the cooperative approach 
employed to date but intends to closely monitor the participation of 
state agencies in this effort. The EPA understands the concerns of some 
state agencies regarding the need for a HAP data reporting rule and 
may, should the need arise, revisit this issue in the future.

J. Revisions to Specific Data Elements

    The NOX SIP Call rule and the CERR contain detailed 
lists of required data elements in addition to emissions, and each rule 
has its own set of definitions. The two sets of data elements overlap 
but are not identical. The NOX SIP Call rule requires a few 
more data elements to be reported and defines some data elements 
differently than the CERR. The EPA reviewed both lists in light of more 
recent reporting experiences and EPA's insight into the difficulty 
states face in collecting and submitting these data elements and their 
utility to EPA, other states, and other users. We proposed to combine 
the separate lists of required elements for the NOX SIP Call 
and the CERR into a single new list in this rule. The EPA proposed that 
the following data elements from the NOX SIP Call be 
eliminated: ``Area Designation'', ``Federal ID code (plant)'', 
``Federal ID code (point)'', ``Federal ID code (process)'', ``Federal 
ID code (stack number)'', ``Maximum design rate'', ``Work weekday 
emissions'', ``Secondary control efficiency'', ``Source of fuel heat 
content data'', ``Source of activity/throughput data'', ``Source of 
emission factor,'' and ``Source of emissions data''. We proposed that 
these relatively minor changes become applicable starting with the 
first required emissions reports following promulgation of this rule.
    There were a number of data elements required in the proposed 
amendments on which we invited comment as to whether they should be 
dropped in the final amendments based upon their current usefulness and 
sufficiency. These were heat content (fuel), ash content (fuel), sulfur 
content (fuel) for fuels other than coal, activity/throughput, hours 
per day in operation, days per week in operation, weeks per year in 
operation, and start time in the day. These data elements were carried 
forward from emissions reporting systems previously used by EPA.
    At present, states are required to report three particular data 
elements for point source stacks: stack diameter, exit gas velocity, 
and exit gas flow rate. The requirement to report all three elements is 
redundant since any one of these can be calculated from the other two. 
We invited comment on which of these data elements, if any, to drop 
from the required list. Our preference was to

[[Page 76547]]

collect the data element that was most closely tied to an actual 
operating measurement. Alternatively, we proposed to allow states to 
report either exit gas flow or exit gas velocity, at their option.
    Finally, we proposed to modify 40 CFR part 51.35 to allow states 
that obtained one-third of their necessary emissions estimates from 
point sources and/or prepared one-third of their nonpoint or mobile 
source emissions estimates each year on a rolling basis, to submit 
their data as a single package on the required every third year 
submission date. The existing requirement allows states to report these 
partial emissions estimates annually as they are completed. Our 
proposal required that states accumulate all 3 years of work and then 
make a single data submission by the due date for the triennial 
emission inventory year. The EPA believes that a single submission 
would allow states to correct and/or update data prior to submitting it 
to EPA thereby facilitating a more consistent data set. A single 
submission would also make it more efficient for EPA to quality assure 
the complete data set rather than doing it on a piecemeal basis. There 
would also be increased efficiencies in resolving any identified 
discrepancies with the states.
    Most commenters agreed with EPA's proposal to combine the separate 
lists of required data elements for the CERR and the NOX SIP 
Call into a single new list of required data elements, thus eliminating 
several requirements from the NOX SIP Call: area 
designation, Federal ID code (plant), Federal ID code (point), Federal 
ID code (process), maximum design rate, work weekday emissions, 
secondary control efficiency, source of fuel heat content data, source 
of activity/throughput data, source of emission factor, and source of 
emissions data. Several commenters suggested that the list of data 
elements be maintained in the NIF rather than in this rule to allow for 
changes in required data elements without the need for rulemaking.
    The EPA agrees with the commenters who expressed support for the 
proposed deletion of some data elements related to the NOX 
SIP Call. The data elements for Federal ID Codes (Plant, Point, 
Process, and Stack Number) were assigned to sources subject to the 
NOX SIP Call and perform similar ID functions to the data 
elements in the proposed rule for Facility ID code, Unit ID code, 
Process ID code, and Stack ID code. The NOX SIP Call ID 
codes are redundant with other ID codes in the proposed rule and will 
be deleted.
    The source of fuel heat content data, source of activity/throughput 
data, source of emission factor and source of emissions data are not 
used by EPA and no commenters addressed the need for these data 
elements specifically. Therefore, EPA will delete these data reporting 
requirements as proposed. The EPA notes that a code for ``emission 
calculation method code'' is planned for the EIS, which is similar in 
application to the ``source of emission factor'' data element. The 
``emission calculation method code'' will allow users to indicate 
calculation methods used for developing emission estimates, including 
emission factors, for all inventory sectors.
    Many commenters indicated that the following data elements proposed 
for deletion were used for a variety of applications and should be 
retained: Heat content (fuel), ash content (fuel), sulfur content 
(fuel) for fuels other than coal, activity/throughput, hours per day in 
operation, days per week in operation, weeks per year in operation and 
start time in the day). One commenter supported deleting only the data 
element for ash content (fuel), while several commenters thought that 
the data element for start time should be deleted. Only one commenter 
thought that all the data elements that had been carried forward from 
earlier systems should be deleted.
    The EPA agrees with the majority of commenters that data elements 
for heat content (fuel), as