OAC 252:100-5-2.1
Emission inventory
Cite as Okla. Admin. Code § 252:100-5-2.1
(a) Requirement to file an emission inventory. The owner or operator of any facility that is a
source of regulated air pollutants shall submit a complete annual emission inventory through
DEQ's electronic reporting system or in another manner acceptable by the Division.
(1) General requirements. The inventory shall cover operations during a calendar year and
shall be submitted on or before April 1 of the following year. Upon receiving a written
demonstration of good cause the Director may grant an extension for submittal beyond the
April 1 deadline.
(2) Permit by rule. The owner or operator of a facility registered under a permit by rule in
Subchapter 7, Part 9, shall submit, at a minimum, an annual emission inventory for the 2014
reporting year or the calendar year in which the facility is registered, if the facility is registered
after December 31, 2014, and thereafter according to the following schedule:
(A) For a registered facility with actual emissions greater than 5 tons per year of any
regulated air pollutant (excluding GHGs as individual pollutants and as an aggregate), an
annual emission inventory for that facility shall be submitted for every National Emissions
Inventory (NEI) Three-Year Cycle Inventory year, as defined in 40 CFR Section 51.30(b).
(B) For a registered facility with actual emissions of 5 tons per year or less of any regulated
air pollutant (excluding GHGs as individual pollutants and as an aggregate), an annual
emission inventory for that facility shall be submitted every second National Emissions
Inventory (NEI) Three-Year Cycle Inventory year, as defined in 40 CFR Section 51.30(b),
beginning with the 2020 NEI reporting year.
(3) Permit exempt facilities and de minimis facilities. The owners or operators of permit
exempt facilities or de minimis facilities, as these terms are defined in OAC 252:100-7-1.1,
are not required to submit an annual emission inventory unless annual emissions from the
facility exceed any of the emission thresholds listed in Table 1 in Appendix A to Subpart A of
40 CFR Part 51. In that event, the emission inventory shall be submitted according to the
schedule contained in that table, which is incorporated by reference in Appendix Q to OAC
252:100.
(4) Special inventories. Upon request by the Director, the owner or operator of a facility that
emits or has the potential to emit any regulated air pollutant shall file an emission inventory
with the Division. The Director is authorized to request this inventory when emission related
data is necessary for program planning or compliance with State or Federal rules, regulations,
standards, or requirements.
(b) Content. All inventories submitted to the Division shall include, but shall not be limited to,
the following:
(1) For those emissions subject to a permit, the permitted allowable emissions as set forth
therein.
(2) The amount of the actual emissions of any regulated air pollutant as defined in OAC
252:100-1-3 (excluding GHGs as individual pollutants and as an aggregate), including
quantifiable excess emissions, and the basis for such determination. If the total actual
emissions of any regulated air pollutant from a facility vary from the allowable or from the
previous year's actual by more than 30%, the Department may require the owner or operator
to provide an explanation for the difference in order to determine compliance with the
Oklahoma Clean Air Act or any rule promulgated thereunder, or any permit condition
prescribed or order issued pursuant thereto.
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(2) For those emissions subject to a permit, the permitted allowable emissions as set forth
therein. Greenhouse gases (GHGs), as individual pollutants and as an aggregate, are exempt
from this requirement.
(3) For those emissions not the subject of a permit and when requested by the AQD, a list of
all OAC 252:100 rules setting forth emission limitations applicable to the facility in question
and the maximum yearly allowable for the facility.
(c) Documentation. All calculations and assumptions must be verified by proper documentation.
All supporting data, including actual production, throughput and measurement records along with
engineering calculations and other data utilized in accordance with OAC 252:100-5-2.1(d) must
be maintained for at least 5 years by the current owner or operator at the facility in conjunction
with facility records of the emission inventory. This information must either be submitted to the
Division or made available for inspection upon request.
(d) Method of calculation. The best available data at the time the emission inventory is or should
have been prepared shall be used to determine emissions. It shall be the burden of the owner or
operator to select the best available data, based on an acceptable method of calculation. The
method of calculation used to determine emissions shall be binding upon the owner or operator
and the Division for the purpose of calculating fees under OAC 252:100-5-2.2 unless challenged
by the owner or operator prior to September 1 of the year the inventory is due or by the Division
within six (6) months after the date the inventory is received. Acceptable methods of calculation
for determining actual emissions are:
(1) Emission factors utilized in the issuance of a currently applicable Oklahoma Air Quality
permit(s) for the facility.
(2) Stack tests using appropriate EPA test methods, with advance notification and opportunity
for observation by the Division.
(3) Stack tests using appropriate EPA test methods may be used for determining the emissions
of identical equipment (i.e., same model, same location, and same operating conditions and
parameters) when:
(A) Tests are performed by persons qualified by training and experience to perform said
tests.
(B) Copies of the test results and methods are available for review by the Division.
(4) Continuous emissions monitoring data, when supported by required certification and
calibration data.
(5) Current AP-42 factors or other factors acceptable to the Division.
(6) Manufacturer's test data, when approved by the Division as reliable.
(7) EPA and EPA-contracted industry-specific emission study data when it can be shown to
be applicable to the facility in question and approved for use in the emission inventory by the
Division.
(8) Fuel usage and other mass-balance methods when supported by specific records applicable
to the materials on which the calculations are based and approved for use in the emission
inventory by the Division.
(9) Any other method that can be shown to be reasonably accurate when supported by
engineering data and calculations, and approved for use in the emission inventory by the
Division.
(e) Methods of verification. Emission inventories determined by the Division to be substantially
incomplete or substantially incorrect shall, upon the request of the Division, be subject to
verification if not satisfactorily completed or corrected within a reasonable time. Verification shall
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be accomplished by an appropriate stack test using EPA approved methods, installation of
continuous monitoring equipment, or other methods acceptable to the Division.
(f) Certification. The emission inventory shall contain certification by a responsible official of
the truth, accuracy, and completeness of the document. This certification shall be signed by a
responsible official and shall contain the following language: "I certify, based on information and
belief formed after reasonable inquiry, the statements and information in the document are true,
accurate, and complete."
SUBCHAPTER 7. PERMITS FOR MINOR FACILITIES
PART 1. GENERAL PROVISIONS