Document ID: EPA-R07-OAR-2023-0199-0004
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2023-08-21T04:00Z

MO-464
MEMORANDUM
SUBJECT:	Technical Support Document for Approval of State Plans for Designated Facilities and Pollutants; Control of Emissions from Existing Municipal Solid Waste Landfills; State of Missouri

FROM:	Allyson Prue
		ARD/APPB

TO:		MO-464; EPA-R07-OAR-2023-0199

THRU:	Ward Burns, Acting Branch Chief
      ARD/APPB

SUMMARY: 
On July 25, 2022, EPA received a request from the Missouri Department of Natural Resources (MoDNR) to approve a Clean Air Action (CAA) Section 111(d) plan as well as state rules 10 CSR 10-5.490, Municipal Solid Waste Landfills and 10 CSR 10-6.310, Restriction of Emissions from Municipal Solid Waste Landfills. Rule 10 CSR 10-5.490 applies to landfills located throughout St. Louis City and Franklin, Jefferson, St. Charles, and St. Louis counties. Rule 10 CSR 6.310 applies to landfills located throughout the rest of the state of Missouri. This plan was submitted to fulfill the requirements of the CAA and is responsive to EPA's promulgation of Emissions Guidelines and Compliance Times for municipal solid waste (MSW) landfills and to replace the federal plan to implement the emission guidelines. The purpose of this state plan revision is to address the non-regulatory elements of Clean Air Act Section 111(d) for existing municipal solid waste landfills in Missouri. This plan includes an inventory of affected sources and explains how the state rules fulfill the regulatory requirements needed for EPA to approve the plan. The EPA is also proposing to approve the July 30, 2022 state effective version of 10 CSR 10-5.490 and 10 CSR 10-6.310, which incorporates requirements established in EPA's updated Emission Guidelines, into the Missouri SIP replacing the prior SIP-approved version of the state rule.
The Missouri Air Conservation Commission held a public hearing for the state rules and section 111(d) Plan on January 27, 2022 in Jefferson City, Missouri. The air program accepted comments on the rules from December 1, 2021 through February 3, 2022 and on the State section 111(d) Plan from December 21, 2021 through February 2, 2022. The air program received no comments on the State section 111(d) Plan and received one written comment on each of the two rule makings. 
Pursuant to Section 643.050 of the Missouri Air Conservation Law, the Missouri Air Conservation Commission adopted the State section 111(d) Plan and rule actions as proposed on March 31, 2022. Missouri's 111(d) state plan for MSW landfills and the relevant MoDNR regulations, as well as all other relevant state plan submittal materials may be found in the docket for today's action

State CAA Section 111(d) Plan:
On August 29, 2016, EPA issued new guidelines under 40 CFR Part 60, Subparts XXX and Cf (81 FR 59331 and 81 FR 59275). These actions were taken in accordance with Section 111 of the CAA. 40 CFR Part 60, Subpart Cf acted as a guideline for state plans to address existing sources under 111(d) for MSW landfills that commenced construction, reconstruction, or modification on or before July 17, 2014. After delays caused by legal challenges, EPA issued a final update to the emission guidelines on August 26, 2019.  On May 21, 2021, EPA promulgated a federal plan for the 39 states (including Missouri) which did not have approved state plans to implement the 2016 guideline rule (86 FR 27756).
MoDNR submitted the state plan to address the non-regulatory text elements of the CAA Section 111(d) for existing MSW landfills in Missouri and included two state rule revisions that implement the plan. Components of the submittal include an inventory of designated facilities, reporting and recordkeeping requirements, public participation, and a demonstration of the legal authority to enforce the state plan. The primary purpose of Missouri's request was to approve the state's CAA Section 111(d) plan, which was triggered by EPA finalizing updated emission guidelines for MSW landfills and to replace the federal plan to implement the emission guidelines. 
Implementing Regulations at 40 CFR Part 60, Subpart B, and Procedural Requirements at 40 CFR 62, Subpart A
The regulations at 40 CFR part 60, subpart B, contain general provisions applicable to the adoption and submittal of state plans for controlling designated pollutants from designated facilities. Additionally, 40 CFR part 62, subpart A, provides the procedural framework by which the EPA will approve or disapprove such plans submitted by a state. When designated facilities are located in a state, the state must then develop and submit a plan for the control of the designated pollutant(s). 40 CFR 60.23(a)(1) states that within 9 months after notice of the availability of a final guideline document is published under 40 CFR 60.22(a), each state shall adopt and submit to the Administrator, in accordance with 40 CFR 60.4 of subpart A of this part, a plan for the control of the designated pollutant to which the guideline document applies. 
EPA's Analysis of Missouri's 111(d) Plan
The EPA has evaluated Missouri's 111(d) state plan for MSW landfills to determine whether the state plan meets applicable requirements from the MSW landfills EG at 40 CFR part 60, subpart Cf, and the CAA section 111(d) implementing regulations at 40 CFR part 60, subpart B. This TSD contains the EPA's detailed rationale and discussion of Missouri's 111(d) state plan for MSW landfills.
Missouri's 111(d) state plan for MSW landfills submittal package contains all materials necessary to be deemed administratively and technically complete according to the criteria of 40 CFR part 60, subpart B. Missouri has provided all implementation and enforcement authority for all MSW landfill state plan requirements through revisions to 10 CSR 10-5.490, Municipal Solid Waste Landfills and 10 CSR 10-6.310, Restriction of Emissions from Municipal Solid Waste Landfills. Specifically, MoDNR has incorporated by reference 40 CFR part 62, subpart OOO, into each state rule. Because 40 CFR part 62, subpart OOO contains all requirements that are required to be addressed in state plans by 40 CFR Part 60, Subpart Cf, EPA finds that MoDNR's incorporation by reference of 40 CFR part 62, subpart OOO meets the requirements of 40 CFR Part 60, Subpart Cf.
Together, the State plan and the two state rule revisions address the required elements of CAA Section 111(d) and 40 CFR Part 60, Subparts B and Cf for existing municipal solid waste landfills. EPA finds the submittal to be complete as per the requirements of 40 CFR 60.27. EPA's analysis as to how Missouri's 111(d) submittal meets 40 CFR Part 60, Subpart B, is presented in the table below.

                                       
                                    Element
                                   Citation

                             Regulatory Language 
                            Meets Guideline Element
                                   Citation
                       Narrative Explanation (as needed)
                                   § 60.20 
                                Applicability.
                                     60.20

The provisions of this subpart apply to States upon publication of a final guideline document under § 60.22(a)
                                      Yes
                                Submittal  -  
                                 cover letter
Submittal is a plan from the State of Missouri to meet requirements of CAA section
              111(d) and 40 CFR Part 60, Subpart Cf, requirements
                                   § 60.21 
                                 Definitions.
                                     60.21

See "60.21 Definitions" tab
                                      N/A
                                      N/A
                                      N/A
                                   § 60.22 
                           Publication of guideline 
                             documents, emission 
                               guidelines, and 
                            final compliance times.
                                     60.22

n/a EPA Obligations
                                      N/A
                                      N/A
                                      N/A
                      § 60.23 Adoption and submittal of
                         State plans; public hearings.
                                     60.23
                                       a
                                       1

Unless otherwise specified in the applicable subpart, within 9 months after notice of the availability of a final guideline document is published under § 60.22(a), each State shall adopt and submit to the Administrator, in accordance with § 60.4 of subpart A of this part, a plan for the control of the designated pollutant to which the guideline document applies.
                                      Yes
                                Submittal  -  
                                 cover letter
MDNR adopted and submitted to the EPA its MSW landfills state plan to meet CAA section 111(d) and 40 CFR Part 60, Subpart Cf requirements.

                                     60.23
                                       a
                                       2

Within nine months after notice of the availability of a final revised guideline document is published as provided in § 60.22(d)(2), each State shall adopt and submit to the Administrator any plan revision necessary to meet the requirements of this subpart.
                                      Yes
                                Submittal  -  
                                 cover letter
MDNR revised its previous MSW landfill plan to meet the revised MSW landfills emission guideline requirements at 40 CFR Part 60, Subpart Cf.

                                     60.23
                                       b

If no designated facility is located within a State, the State shall submit a letter of certification to that effect to the Administrator within the time specified in paragraph (a) of this section. Such certification shall exempt the State from the requirements of this subpart for that designated pollutant.
                                      N/A
                                      N/A
                                      N/A

                                     60.23
                                       c
                                       1

Except as provided in paragraphs (c)(2) and (c)(3) of this section, the State shall, prior to the adoption of any plan or revision thereof, conduct one or more public hearings within the State on such plan or plan revision.
                                      Yes
                        Submittal - see page 25 of pdf
MDNR conducted a public hearing on January 27, 2022. Online participation was also available.

                                     60.23
                                       c
                                       2

No hearing shall be required for any change to an increment of progress in an approved compliance schedule unless the change is likely to cause the facility to be unable to comply with the final compliance date in the schedule.
                                      N/A
                                      N/A
                                      N/A

                                     60.23
                                       c
                                       3

No hearing shall be required on an emission standard in effect prior to the effective date of this subpart if it was adopted after a public hearing and is at least as stringent as the corresponding emission guideline specified in the applicable guideline document published under § 60.22(a).
                                      N/A
                                      N/A
                                      N/A

                                     60.23
                                       d

Any hearing required by paragraph (c) of this section shall be held only after reasonable notice. Notice shall be given at least 30 days prior to the date of such hearing and shall include:
                                      Yes
                        Submittal - see page 25 of pdf
MDNR provided public notices on December 21, 2021, which was more than 30 days prior to the public hearing.

                                     60.23
                                       d
                                       1

 Notification to the public by prominently advertising the date, time, and place of such hearing in each region affected;
                                      Yes
                        Submittal - see page 25 of pdf
MDNR provided notice via an email bulletin to the Subscribers of Air Public Notices email group (1688 recipients). The notice included the date, time, and place of the hearing.

                                     60.23
                                       d
                                       2

Availability, at the time of public announcement, of each proposed plan or revision thereof for public inspection in at least one location in each region to which it will apply;
                                      Yes
                        Submittal - see page 27 of pdf
MDNR's public announcement included information on the availability of the proposed state plan. The proposed state plan was available electronically to the public through the MDNR website.

                                     60.23
                                       d
                                       3

Notification to the Administrator;
                                      Yes
                                      N/A
             EPA received notification of the proposed state plan.

                                     60.23
                                       d
                                       4

Notification to each local air pollution control agency in each region to which the plan or revision will apply; and
                                      N/A
                                      N/A
                                      N/A

                                     60.23
                                       d
                                       5

In the case of an interstate region, notification to any other State included in the region.
                                      N/A
                                      N/A
                                      N/A

                                     60.23
                                       e

The State shall prepare and retain, for a minimum of 2 years, a record of each hearing for inspection by any interested party. The record shall contain, as a minimum, a list of witnesses together with the text of each presentation.
                                      N/A
                                      N/A
MDNR heald a public hearing on January 27, 2022; the record of that hearing is subject to the 2 year retention requirement.

                                     60.23
                                       f

The State shall submit with the plan or revision
                                       -
                                       -
                                       -

                                     60.23
                                       f
                                       1

 Certification that each hearing required by paragraph (c) of this section was held in accordance with the notice required by paragraph (d) of this section; and
                                      Yes
                        Submittal - see page 141 of pdf
MDNR included all required documentation demonstrating that the public hearing was announced and held in accordance with Subpart B requirements.

                                     60.23
                                       f
                                       2

A list of witnesses and their organizational affiliations, if any, appearing at the hearing and a brief written summary of each presentation or written submission.
                                      Yes
                         Submittal - see pages 29, 30
MDNR did not provide a list of participants but did not receive any comments on the proposed plan, during public hearing or the public comment period. MDNR included a transcript of the applicable portion of the public meeting and states the commissioners that were present and who presented for the plan.

                                     60.23
                                       g

Upon written application by a State agency (through the appropriate Regional Office), the Administrator may approve State procedures designed to insure public participation in the matters for which hearings are required and public notification of the opportunity to participate if, in the judgment of the Administrator, the procedures, although different from the requirements of this subpart, in fact provide for adequate notice to and participation of the public. The Administrator may impose such conditions on his approval as he deems necessary. Procedures approved under this section shall be deemed to satisfy the requirements of this subpart regarding procedures for public hearings.
                                      N/A
                                      N/A
                                      N/A
             § 60.24 Emission standards and compliance schedules.
                                     60.24
                                       a

 Each plan shall include emission standards and compliance schedules.
                                      Yes
                        Submittal - see page 146 of pdf
                               10 CSR 10-5.490 
                                10 CSR 10-6.310
Emission standards and compliance schedules are included in the submitted plan and incorporated by reference into 10 CSR 10-5.490 and 10 CSR 10-6.310. A generic compliance and increments of progress schedule is included in the submittal.
10 CSR 10-6.310 applies identical emission limitations as those established in the federal plan (Part 62, Subpart OOO) as well as identical compliance times. 10 CSR 10-5.490 also
applies identical emission limitations except that the rule lowers the design capacity and emission thresholds that require the installation and operation of a GCCS. 10 CSR 10-5.490 also applies identical compliance times except that the compliance schedule begins to apply to landfills at lower design capacities and emission thresholds than the federal plan.

                                     60.24
                                       b
                                       1

Emission standards shall either be based on an allowance system or prescribe allowable rates of emissions except when it is clearly impracticable. Such cases will be identified in the guideline documents issued under § 60.22. Where emission standards prescribing equipment specifications are established, the plan shall, to the degree possible, set forth the emission reductions achievable by implementation of such specifications, and may permit compliance by the use of equipment determined by the State to be equivalent to that prescribed.
                                      Yes
                               10 CSR 10-5.490 
                                10 CSR 10-6.310
See response to 60.24(a): emission guideline requirements of 40 CFR 60.33f (40 CFR 62.16714) are found in 10 CSR 10-5.490 and 10 CSR 10-6.310. Requirements are incorporated by reference.

                                     60.24
                                       b
                                       2

Test methods and procedures for determining compliance with the emission standards shall be specified in the plan. Methods other than those specified in appendix A to this part may be specified in the plan if shown to be equivalent or alternative methods as defined in § 60.2 (t) and (u).
                                      Yes
                                10 CSR 10-5.490
                                10 CSR 10-6.310
The MSW landfill state plan references test methods and procedures contained in 40 CFR 62 Subpart OOO, which are consistent with the provisions of 40 CFR 60 Subpart Cf.

                                     60.24
                                       b
                                       3

Emission standards shall apply to all designated facilities within the State. A plan may contain emission standards adopted by local jurisdictions provided that the standards are enforceable by the State.
                                      Yes
                                10 CSR 10-5.490
                                10 CSR 10-6.310
Emission standards apply to all designated facilities within the State. No local jurisdiction adoption is included in the plan or rules.

                                     60.24
                                       c

Except as provided in paragraph (f) of this section, where the Administrator has determined that a designated pollutant may cause or contribute to endangerment of public health, emission standards shall be no less stringent than the corresponding emission guideline(s) specified in subpart C of this part, and final compliance shall be required as expeditiously as practicable but no later than the compliance times specified in subpart C of this part.
                                      Yes
                               10 CSR 10-5.490 
                                10 CSR 10-6.310
Both rules are identical to the emission limitations established in the federal plan, except that 10 CSR 10-5.490 (St Louis area rule) lowers the design capacity and emission thresholds that require the installation and operation of a GCCS.

                                     60.24
                                       d

Where the Administrator has determined that a designated pollutant may cause or contribute to endangerment of public welfare but that adverse effects on public health have not been demonstrated, States may balance the emission guidelines, compliance times, and other information provided in the applicable guideline document against other factors of public concern in establishing emission standards, compliance schedules, and variances. Appropriate consideration shall be given to the factors specified in § 60.22(b) and to information presented at the public hearing(s) conducted under § 60.23(c).
                                      N/A
                                      N/A
                                      N/A

                                     60.24
                                       e
                                       1

Any compliance schedule extending more than 12 months from the date required for submittal of the plan must include legally enforceable increments of progress to achieve compliance for each designated facility or category of facilities. Unless otherwise specified in the applicable subpart, increments of progress must include, where practicable, each increment of progress specified in § 60.21(h) and must include such additional increments of progress as may be necessary to permit close and effective supervision of progress toward final compliance.
                                      Yes
                               10 CSR 10-5.490 
                                10 CSR 10-6.310
The compliance schedule, including increments of progress, as specified in 40 CFR 60.32f (40 CFR 62.16712) and 60.38f(c) (40 CFR 62.16724(c)) and the increments of progress are incorporated into 10 CSR 10-5.490 and 10 CSR 10-6.310.

                                     60.24

                                       2

A plan may provide that compliance schedules for individual sources or categories of sources will be formulated after plan submittal. Any such schedule shall be the subject of a public hearing held according to § 60.23 and shall be submitted to the Administrator within 60 days after the date of adoption of the schedule but in no case later than the date prescribed for submittal of the first semiannual report required by § 60.25(e).
                                      N/A
                                      N/A
                                      N/A

                                     60.24
                                       f

Unless otherwise specified in the applicable subpart on a case-by-case basis for particular designated facilities or classes of facilities, States may provide for the application of less stringent emissions standards or longer compliance schedules than those otherwise required by paragraph (c) of this section, provided that the State demonstrates with respect to each such facility (or class of facilities):
                                      N/A
                                      N/A
                                      N/A

                                     60.24

                                       1

Unreasonable cost of control resulting from plant age, location, or basic process design;
                                      N/A
                                      N/A
                                      N/A

                                     60.24

                                       2

Physical impossibility of installing necessary control equipment; or
                                      N/A
                                      N/A
                                      N/A

                                     60.24

                                       3

Other factors specific to the facility (or class of facilities) that make application of a less stringent standard or final compliance time significantly more reasonable.
                                      N/A
                                      N/A
                                      N/A

                                     60.24
                                       g

Nothing in this subpart shall be construed to preclude any State or political subdivision thereof from adopting or enforcing (1) emission standards more stringent than emission guidelines specified in subpart C of this part or in applicable guideline documents or (2) compliance schedules requiring final compliance at earlier times than those specified in subpart C or in applicable guideline documents.
                                      Yes
                               10 CSR 10-5.490 
10 CSR 10-5.490 also applies identical emission limitations except that the rule lowers the design capacity and emission thresholds that require the installation and operation of a GCCS. 10 CSR 10-5.490 also applies identical compliance times except that the compliance schedule begins to apply to landfills at lower design capacities and emission thresholds than the federal plan.
                    § 60.25 Emission inventories, source 
                            surveillance, reports.
                                     60.25
                                       a

Each plan shall include an inventory of all designated facilities, including emission data for the designated pollutants and information related to emissions as specified in appendix D to this part. Such data shall be summarized in the plan, and emission rates of designated pollutants from designated facilities shall be correlated with applicable emission standards. As used in this subpart, "correlated" means presented in such a manner as to show the relationship between measured or estimated amounts of emissions and the amounts of such emissions allowable under applicable emission standards.
                                      Yes
                     Submittal - see page 142 - 145 of pdf
MDNR included an inventory of all designated facililities, including location, emission data, open/closed status, and if GCCS has been installed.

                                     60.25
                                       b
                                       1

Legally enforceable procedures for requiring owners and operators of designated facilities to maintain records and periodically report to the State information on the nature and amount of emissions from such facilities, and/or such information as may be necessary to enable the State to determine whether such facilities comply with applicable portions of the plan
                                      Yes
                        Submittal - see page 148 of pdf
                               10 CSR 10-5.490 
                                10 CSR 10-6.310
The recordkeeping and reporting requirements under 40 CFR 60.38f (40 CFR 62.16724) and 60.39f (40 CFR 62.16726) are incorporated by reference into 10 CSR 10-5.490 and 10 CSR 10-6.310.
Both rules are identical to the federal plan requirements for MSW landfills with respect to recordkeeping and reporting except that they require that any report that is required to be submitted to EPA under the rule, the landfill must also submit a copy of the report to MDNR.

                                     60.25
                                       b
                                       2

Periodic inspection and, when applicable, testing of designated facilities. 
                                      Yes
                          RSMo Chapter 643 (643.050)
Chapter 643 of the Revised Statues of Missouri (RSMo), Air Conservation, gives MACC the authority to promulate rules and regulations to establish standards and guidelines that ensure the State of Missouri complies with the provisions of the CAA. The RSMo includes the right to inspect at designated facilities.

                                     60.25
                                       c

Each plan shall provide that information obtained by the State underparagraph (b) of this section shall be correlated with applicable emission standards (see §60.25(a)) and made available to the general public. 
                                      Yes
                               RSMo Chapter 643 
                             (643.050.1(3)(a) and 
                                  643.192.2)
                                10 CSR 10-6.030
                                10 CSR 10-6.110
Chapter 643 of the RSMo authorizes MDNR to require persons engageed in operations which result in air pollution to monitor or test emissions and to file reports containing information related to rate, period of emission, and composition of effluent
(643.050.1(3)(a)). Chapter 643 of the RSMo also requires annual reports that summarize changes in air quality (643.192.2).
10 CSR 10-6.030 contains sampling methods for testing emission sources and 10 CSR 10-6.110 requires that a permitted source file annual reports of emissions and emissions air data. Air program makes this data available to the public upon request.

                                     60.25
                                       d

The provisions referred to in paragraphs (b) and (c) of this section shall be specifically identified. Copies of such provisions shall be submitted with the plan unless:

                                       

                                     60.25
                                       d
                                       1

They have been approved as portions of a preceding plan submitted under this subpart or as portions of an implementation plan submitted under section 110 of the Act, and

                                       

                                     60.25
                                       d
                                       2

The State demonstrates:

                                       

                                     60.25
                                       d
                                       2
                                       i

That the provisions are applicable to the designated pollutant(s) for which the plan is submitted, and

                                       

                                     60.25
                                       d
                                       2
                                      ii

That the requirements of § 60.26 are met.

                                       

                                     60.25
                                       e

The State shall submit reports on progress in plan enforcement to the Administrator on an annual (calendar year) basis, commencing with the first full report period after approval of a plan or after promulgation of a plan by the Administrator. 
Information required under this paragraph must be included in the annual report required by § 51.321 of this chapter.
                                      Yes
                        Submittal - see page 148 of pdf
MDNR will incorporate the required annual progress reporting elements for this state plan into the reports required by 40 CFR 51.321, 40 CFR 60.25(e), and 40 CFR 60.25(f).

                                     60.25
                                       f

Each progress report shall include:
                                       -
                                       -
                                       -

                                     60.25
                                       f
                                       1

Enforcement actions initiated against designated facilities during the reporting period, under any emission standard or compliance schedule of the plan.
                                      Yes
                        Submittal - see page 148 of pdf
                        See above reponse to 60.25(e).

                                     60.25
                                       f
                                       2

 Identification of the achievement of any increment of progress required by the applicable plan during the reporting period.
                                      Yes
                        Submittal - see page 148 of pdf
                        See above reponse to 60.25(e).

                                     60.25
                                       f
                                       3

Identification of designated facilities that have ceased operation during the reporting period.
                                      Yes
                        Submittal - see page 148 of pdf
                        See above reponse to 60.25(e).

                                     60.25
                                       f
                                       4

Submission of emission inventory data as described in paragraph (a) of this section for designated facilities that were not in operation at the time of plan development but began operation during the reporting period.
                                      Yes
                        Submittal - see page 148 of pdf
                        See above reponse to 60.25(e).

                                     60.25
                                       f
                                       5

Submission of additional data as necessary to update the information submitted under paragraph (a) of this section or in previous progress reports.
                                      Yes
                        Submittal - see page 148 of pdf
                        See above reponse to 60.25(e).

                                     60.25
                                       f
                                       6

Submission of copies of technical reports on all performance testing on designated facilities conducted under paragraph (b)(2) of this section, complete with concurrently recorded process data.
                                      Yes
                        Submittal - see page 148 of pdf
                        See above response to 60.25(e).
                             60.26 Legal Authority
                                     60.26
                                       a

Each plan shall show that the State has legal authority to carry out the plan, including authority to:
                                      Yes
                        Submittal - see page 142 of pdf
                              Chapter 643 of the 
                                     RSMo
The Missouri Air Conservation Commission (MACC) has the legal authority to implement and enforce Section 111(d) State Plan for MSW landfills in Missouri.
Chapter 643 of the Revised Statues of Missouri (RSMo), Air Conservation, gives MACC the authority to promulate rules and regulations to establish standards and guidelines that ensure the State of Missouri complies with the provisions of the CAA.

                                     60.26
                                       a
                                       1

Adopt emission standards and compliance schedules applicable to designated facilities.
                                      Yes
                              Chapter 643 of the 
                                     RSMo
Chapter 643 of the Revised Statues of Missouri (RSMo), Air Conservation, gives MACC the authority to promulate rules and regulations to establish standards and guidelines that ensure the State of Missouri complies with the provisions of the CAA.

                                     60.26
                                       a
                                       2

Enforce applicable laws, regulations, standards, and compliance schedules, and seek injunctive relief.
                                      Yes
                              Chapter 643 of the 
                                     RSMo
Chapter 643 of the Revised Statues of Missouri (RSMo), Air Conservation, gives MACC the authority to promulate rules and regulations to establish standards and guidelines that ensure the State of Missouri complies with the provisions of the CAA.

                                     60.26
                                       a
                                       3

Obtain information necessary to determine whether designated facilities are in compliance with applicable laws, regulations, standards, and compliance schedules, including authority to require recordkeeping and to make inspections and conduct tests of designated facilities.
                                      Yes
                              Chapter 643 of the 
                                     RSMo
Chapter 643 of the Revised Statues of Missouri (RSMo), Air Conservation, gives MACC the authority to promulate rules and regulations to establish standards and guidelines that ensure the State of Missouri complies with the provisions of the CAA.

                                     60.26
                                       a
                                       4

Require owners or operators of designated facilities to install, maintain, and use emission monitoring devices and to make periodic reports to the State on the nature and amounts of emissions from such facilities; also authority for the State to make such data available to the public as reported and as correlated with applicable emission standards.
                                      Yes
                              Chapter 643 of the 
                                     RSMo
Chapter 643 of the Revised Statues of Missouri (RSMo), Air Conservation, gives MACC the authority to promulate rules and regulations to establish standards and guidelines that ensure the State of Missouri complies with the provisions of the CAA.

                                     60.26
                                       b

The provisions of law or regulations which the State determines provide the authorities required by this section shall be specifically identified. Copies of such laws or regulations shall be submitted with the plan unless:
                                      Yes
                     Submittal - see pages 141-142 of pdf 
Authorites have been specifically identified. Copies of the statue were not provided but are available to the public online. The plan demonstrates that the regulations are applicable to the designated pollutants.

                                     60.26
                                       b
                                       1

They have been approved as portions of a preceding plan submitted under this subpart or as portions of an implementation plan submitted under section 110 of the Act, and

                                       

                                     60.26
                                       b
                                       2

The State demonstrates that the laws or regulations are applicable to the designated pollutant(s) for which the plan is submitted.

                                       

                                     60.26
                                       c

The plan shall show that the legal authorities specified in this section are available to the State at the time of submission of the plan. Legal authority adequate to meet the requirements of paragraphs (a)(3) and (4) of this section may be delegated to the State under section 114 of the Act.
                                      Yes
                        Submittal - see page 142 of pdf
The plan specifies the legal authorities that were available to MDNR at the time of the submission of the plan.

                                     60.26
                                       d

A State governmental agency other than the State air pollution control agency may be assigned responsibility for carrying out a portion of a plan if the plan demonstrates to the Administrator's satisfaction that the State governmental agency has the legal authority necessary to carry out that portion of the plan
                                      N/A
                                      N/A
                                      N/A

                                     60.26
                                       e

 The State may authorize a local agency to carry out a plan, or portion thereof, within the local agency's jurisdiction if the plan demonstrates to the Administrator's satisfaction that the local agency has the legal authority necessary to implement the plan or portion thereof, and that the authorization does not relieve the State of responsibility under the Act for carrying out the plan or portion thereof.
                                      N/A
                                      N/A
                                      N/A
                    § 60.27 Actions by the Administrator.
                                     60.27
                                       a

The Administrator may, whenever he determines necessary, extend the period for submission of any plan or plan revision or portion thereof.
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       b

 After receipt of a plan or plan revision, the Administrator will propose the plan or revision for approval or disapproval. The Administrator will, within four months after the date required for submission of a plan or plan revision, approve or disapprove such plan or revision or each portion thereof.
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       c

The Administrator will, after consideration of any State hearing record, promptly prepare and publish proposed regulations setting forth a plan, or portion thereof, for a State if:
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       c
                                       1

The State fails to submit a plan within the time prescribed;
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       c
                                       2

The State fails to submit a plan revision required by § 60.23(a)(2) within the time prescribed; or
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       c
                                       3

The Administrator disapproves the State plan or plan revision or any portion thereof, as unsatisfactory because the requirements of this subpart have not been met.
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       d

The Administrator will, within six months after the date required for submission of a plan or plan revision, promulgate the regulations proposed under paragraph (c) of this section with such modifications as may be appropriate unless, prior to such promulgation, the State has adopted and submitted a plan or plan revision which the Administrator determines to be approvable.
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       e
                                       1

 Except as provided in paragraph (e)(2) of this section, regulations proposed and promulgated by the Administrator under this section will prescribe emission standards of the same stringency as the corresponding emission guideline(s) specified in the final guideline document published under § 60.22(a) and will require final compliance with such standards as expeditiously as practicable but no later than the times specified in the guideline document.
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       e
                                       2

Upon application by the owner or operator of a designated facility to which regulations proposed and promulgated under this section will apply, the Administrator may provide for the application of less stringent emission standards or longer compliance schedules than those otherwise required by this section in accordance with the criteria specified in § 60.24(f).
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       f

Prior to promulgation of a plan under paragraph (d) of this section, the Administrator will provide the opportunity for at least one public hearing in either:
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       f
                                       1

Each State that failed to hold a public hearing as required by § 60.23(c); or
                                      N/A
                                      N/A
                                      N/A

                                     60.27
                                       f
                                       2

Washington, DC or an alternate location specified in the Federal Register.
                                      N/A
                                      N/A
                                      N/A
                       60.28 Plan revisions by the State.
                                     60.28
                                       a

 Plan revisions which have the effect of delaying compliance with applicable emission standards or increments of progress or of establishing less stringent emission standards shall be submitted to the Administrator within 60 days after adoption in accordance with the procedures and requirements applicable to development and submission of the original plan.
                                      N/A
                                      N/A
                                      N/A

                                       b

More stringent emission standards, or orders which have the effect of accelerating compliance, may be submitted to the Administrator as plan revisions in accordance with the procedures and requirements applicable to development and submission of the original plan.
                                      N/A
                                      N/A
                                      N/A

                                       c

 A revision of a plan, or any portion thereof, shall not be considered part of an applicable plan until approved by the Administrator in accordance with this subpart.
                                      N/A
                                      N/A
                                      N/A
                   60.29 Plan revisions by the Administrator.

After notice and opportunity for public hearing in each affected State, the Administrator may revise any provision of an applicable plan if:
                                      N/A
                                      N/A
                                      N/A

                                       a

The provision was promulgated by the Administrator, and
                                      N/A
                                      N/A
                                      N/A

                                       b

The plan, as revised, will be consistent with the Act and with the requirements of this subpart.
                                      N/A
                                      N/A
                                      N/A

RULE REVISIONS:
Below is EPA's description of the changes made to each rule section and the text of the revised rule.
Revisions that are additions to MoDNR's existing approved rule text are bold. Revisions that are deletions to the existing approved SIP rule text are stricken through. The rule text with changes is listed first and is followed by a summary of the EPA's review of the changes.

10 CSR 10-5.490 Municipal Solid Waste Landfills

(1)	 Applicability.

      (A) 	This rule applies to all municipal solid waste (MSW) 		landfills located in the St. Louis ozone nonattainment area 	(Jefferson, Franklin, St. Charles, St. Louis Counties, and 	St. Louis City) throughout St. Louis City and Franklin, 	Jefferson, St. Charles, and St. Louis counties that have 	accepted waste any time since November 8, 1987, or have 	additional capacity available for future waste deposition, 	and that commenced construction, reconstruction, or 	modification on or before July 17, 2014. Landfills that 	commenced construction, reconstruction or modification 	after July 17, 2014, are covered under the Environmental 	Protection Agency's New Source Performance Standard for 	Municipal Solid Waste Landfills 40 CFR 60, Subpart XXX.
      
      (B)	 For purposes of obtaining an operating permit under 	Title V of the Clean Air Act, the owner or operator of an 	MSW landfill subject to this rule with a design capacity 	less than two and one-half (2.5) million megagrams or two 	and one-half (2.5) million cubic meters is not subject to 	the requirements to obtain an operating permit for the 	landfill under 40 Code of Federal Regulations (CFR) 70 or 	71, unless the landfill is otherwise subject to either 40 	CFR 70 or 71. For purposes of submitting a timely 	application for an operating permit under 40 CFR 70 or 71, 	the owner or operator of an MSW landfill subject to the 	rule with a design capacity greater than or equal to two 	and one-half (2.5) million megagrams and two and one-half 	(2.5) million cubic meters on the effective date of EPA 	approval of the state's program under section 111(d) of the 	Clean Air Act (June 23, 1998), and not otherwise subject to 	either 40 CFR 70 or 71, becomes subject to the requirements 	of 40 CFR 70.5(a)(1)(i) or 71.5(a)(1)(i) ninety (90) days 	after the effective date of such 111(d) program approval, 	even if the design capacity report is submitted earlier.
      
      (C)	 When an MSW landfill subject to this rule is closed, 
      the owner or operator is no longer subject to the 	requirement to maintain an operating permit under 40 CFR 70 	or 71 for the landfill if the landfill is not otherwise 	subject to the requirements of either 40 CFR 70 or 71 and 	if either of the following conditions is met:
      1. The landfill was never subject to a requirement for		a control system under section (3) of this rule; or
      2. The owner or operator meets the conditions for 	control system removal specified in section 	60.752(b)(2)(v) of 40 CFR 60, Subpart WWW.
      
      (D)(B)	Physical or operational changes made to an 	existing MSW landfill solely to comply with this rule are 	not considered construction, reconstruction, or 	modification for the purposes of this rule and would not 	subject an existing MSW landfill to the requirements of 40 	CFR 60, subpart XXX.
      
(2) 	Definitions. Definitions of certain terms specified in this rule may be found in 10 CSR 10-6.020. The provisions of 40 CFR
62.16730, promulgated as of July 1, 2021, including the revision published at 87 FR 8203 (effective February 14, 2022), are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions. The definitions of 40 CFR 62.16730 apply, except that anywhere two and one half (2.5) million mega-grams (Mg) and two and one half (2.5) million cubic meters (M3) appears in 40 CFR 62.16730, it shall be replaced with one (1.0) million Mg and one (1.0) million m3 for the purposes of this rule.

(3)	 General Provisions. The provisions of 40 CFR 62.16711(e) and (f), 40 CFR 62.16712 through 62.16716, 40 CFR 62.16720 through 62.16722, 40 CFR 62.16728, and Table 1 to Subpart OOO of Part 62, promulgated as of July 1, 2021, including the revision published at 87 FR 8203 (effective February 14, 2022), are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions. Owners and operators of MSW landfills subject to this rule must comply with the following:

      (A) 	Title V operating permit requirements -- 40 CFR 	62.16711(e);
      (B) 	Exemptions for Part 70 operating permit requirements 	for closed landfills -- 40 CFR 62.16711(f);
      (C) 	Compliance schedule and increments of progress -- 40 CFR		62.16712 and Table 1 in Subpart OOO of Part 62 applies, 	except that for the purposes of this rule -- 
      1. One (1.0) million Mg and one (1.0) million m3 shall 	replace two and one half (2.5) million Mg and two and 	one half (2.5) million m3 as it appears in 40 CFR 	62.16712; and
      2. Twenty-five (25) Mg shall replace thirty-four (34) 	Mg and fifty (50) Mg as it appears in 40 CFR 62.16712 	and Table 1 to Subpart OOO of Part 62;
      (D)	Standards for municipal solid waste landfill 	emissions -- 40 CFR 62.16714 applies, except that for the 	purposes of this rule -- 
      1. One (1.0) million Mg and one (1.0) million m3 shall 	replace two and one half (2.5) million Mg and two and 	one half (2.5) million m3 as it appears in 40 CFR 	62.16714; and
      2. Twenty-five (25) Mg shall replace thirty-four (34) 	Mg and fifty (50) Mg as it appears in 40 CFR 62.16714;
      (E)	Operational standards for collection and control 			systems -- 40 CFR 62.16716;
      (F) 	Compliance provisions -- 40 CFR 62.16720;
      (G)	Monitoring of operations -- 40 CFR 62.16722; and
      (H)	Specifications for active collection systems -- 40 CFR 	62.16728.
      
(4) 	Reporting and Record Keeping. The provisions of 40 CFR 62.16711(g) and (h), and 40 CFR 62.16724 through 62.16726, promulgated as of July 1, 2021, are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions. Owners and operators of MSW landfills subject to this rule must comply with the following:

      (A) 	Reporting guidelines -- 40 CFR 62.16724 applies, except 	that for the purposes of this rule -- 
      1. One (1.0) million Mg and one (1.0) million m3 shall 	replace two and one half (2.5) million Mg and two and 	one half (2.5) million m3 as it appears in 40 CFR 	62.16724; and
      2. Twenty-five (25) Mg shall replace thirty-four (34) 	Mg and fifty (50) Mg as it appears in 40 CFR 62.16724;
      (B) 	Reporting Exemptions -- 
            1. Exemptions for reporting requirements for closed landfills -- 40 CFR 62.16711(g) applies, except that for the purposes of this rule, twenty-five (25) Mg shall replace fifty (50) Mg as it appears in 40 CFR 62.16711(g); and
            2. Exemptions for reporting requirements for legacy controlled landfills -- 40 CFR 62.16711(h); and
      (C) 	Recordkeeping guidelines -- 40 CFR 62.16726 applies, 	except that for the purposes of this rule, one (1.0) 	million Mg and one (1.0) million m3 shall replace two and 	one half (2.5) million Mg and two and one half (2.5) 	million m3 as it appears in 40 CFR 62.16726.
      
(5) 	Test Methods. The provisions of 40 CFR 62.16718, promulgated as of July 1, 2021, are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions. The provisions of 40 CFR 62.16718 apply, except that for the purposes of this rule, twenty-five (25) Mg shall replace thirty-four (34) Mg as it appears in 40 CFR 62.16718.

EPA Analysis:  The amendment to 10 CSR 10-5.490 references 40 CFR Part 62 Subpart OOO instead of having the language explicitly laid out in the rule. This reference allows for flexibility in updating the state rule in response to future changes to federal requirements. 

This TSD does not include the redline for a section of language that was removed between Sections (2) and (3). The removed language was federal text from the prior emission guidelines that were not previously incorporated by reference. The redline language can be found on pages 67-95 of the MoDNR Landfill 111(d) Plan and State Rules submittal document. Additionally, the redline for Section (2) was missing language that was included in the rules published in the Missouri Code of State Regulations (CSR). The redline for this TSD for Section (2) was completed using language from the Missouri CSR, located on page 3 of the MoDNR submittal document. 

In the previous municipal solid waste landfill rule (40 CFR Part 60, Subpart WWW), an NMOC value calculated at greater than 50 Mg per year at MSW landfills with a design capacity greater than or equal to 2.5 million Mg and 2.5 million m[3] requires installation of a gas collection and control system (GCCS). The new rule, as per 40 CFR Part 62, Subpart OOO, requires installation of a GCCS for landfills of the same design capacity and an NMOC value of 34 Mg per year or greater. The amendment to 10 CSR 10-5.490 includes more stringent emission thresholds (25 Mg per year NMOC) and design capacities (1.0 million Mg and 1.0 million m[3]) to the federal rules but remain unchanged from the previous SIP. Because these thresholds remain the same between the previously approved rule in the SIP and the proposed revision, and because Missouri has incorporated by reference 40 CFR Part 62, Subpart OOO, which is more stringent than the previous SIP-approved version of 10 CSR 10-5.490, in accordance with CAA Section 110(l), EPA finds that the plan does not interfere with any applicable requirement concerning attainment and reasonable further progress or any other applicable requirement of the CAA. Therefore, EPA proposes to approve the rule revisions as meeting the requirements of CAA Section 111(d) as well as approve the revisions into the Missouri SIP.

10 CSR 10-6.310 Restriction of Emissions from Municipal Solid Waste Landfills

       Applicability.

      (A) 	This rule applies to each municipal solid waste (MSW) landfill for which that has accepted waste at any time since November 8, 1987, or has additional design capacity available for future waste deposition, and that commenced construction, reconstruction or modification was commenced on or before May 30, 1991, and has accepted waste at any time since November 8, 1987, or has additional design capacity available for future waste deposition July 17, 2014. Landfills for which for which construction, reconstruction or modification was commenced on May 30, 1991, or after July 17, 2014, are covered under subject to the requirements of the Environmental Protection Agency's New Source Performance Standard for Municipal Solid Waste Landfills 40 CFR 60, Subpart XXX.

      (B) Physical or operational changes made to an existing MSW 	landfill solely to comply with this rule are not considered 	construction, reconstruction, or modification for the 	purposes of this rule and do not subject an existing MSW 	landfill to the requirements of 40 CFR 60, Subpart XXX.
      (C) MSW landfills covered by 10 CSR 10- 5.490 are exempt 	from this rule.
      
      (D) For purposes of obtaining an operating permit under 	Title V of the Clean Air Act, the owner or operator of an 	MSW landfill subject to this rule with a design capacity 	less than two and one-half (2.5) million megagrams or two 	and one-half (2.5) million cubic meters is not subject to 	the requirements to obtain an operating permit for the		
      landfill under 40 Code of Federal Regulations (CFR) 70 or 	71, unless the landfill is otherwise subject to either 40 	CFR 70 or 71. For purposes of submitting a timely 	application for an operating permit under 40 CFR 70 or 71,	the owner or operator of an MSW landfill subject to the 	rule with a design capacity greater than or equal to two 	and one-half (2.5) million megagrams and two and one-half 	(2.5) million cubic meters on the effective date of EPA 	approval of the state's program under section 111(d) of the 	Clean Air Act (June 23, 1998), and not otherwise subject to 	either 40 CFR 70 or 71, becomes subject to the requirements 	of 40 CFR 70.5(a)(1)(i) or 71.5(a)(1)(i)ninety (90) days 	after the effective date of such 111(d) program approval,		even if the design capacity report is submitted earlier.
      
      (E) When an MSW landfill subject to this rule is closed, 	the owner or operator is no longer subject to the 	requirement to maintain an operating permit under 40 CFR 70 	or 71 for the landfill if the landfill is not otherwise 	subject to the requirements of either 40 CFR 70 or 71 and 	if either of the following conditions is met:
      
      1. The landfill was never subject to a requirement for 	a control system under section (3) of this rule; or
            2. The owner or operator meets the conditions for control system removal specified in section 60.752(b)(2)(v) of subpart WWW.
            
(2)	 Definitions. Definitions of certain terms specified in this rule may be found in 10 CSR 10-6.020. The provisions of 40 CFR 62.16730, promulgated as of July 1, 2021, including the revision published at 87 FR 8203 (effective February 14, 2022), shall apply and are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions.

(3) 	General Provisions. The provisions of 40 CFR 62.16711(e) and (f), 40 CFR 62.16712 through 62.16716, 40 CFR 62.16720 through 62.16722, and 40 CFR 62.16728, promulgated as of July 1, 2021, including the revision published at 87 FR 8203 (effective February 14, 2022), are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions. Owners and operators of MSW landfills subject to this rule must comply with the following:

      (A) Title V operating permit requirements -- 40 CFR 	62.16711(e);
      (B) Exemptions for Part 70 operating permit requirements 	for closed landfills -- 40 CFR 62.16711(f);
      (C) Compliance schedule and increments of progress -- 40 CFR 	62.16712;
      (D) Standards for municipal solid waste landfill emissions -- 	40 CFR 62.16714;
      (E) Operational standards for collection and control 	systems -- 40 CFR 62.16716;
      (F) Compliance provisions -- 40 CFR 62.16720;
      (G) Monitoring of operations -- 40 CFR 62.16722; and
      (H) Specifications for active collection systems -- 40 CFR 	62.16728.
      
(4) 	Reporting and Record Keeping. The provisions of 40 CFR 62.16711(g) and (h), and 40 CFR 62.16724 through 62.16726, promulgated as of July 1, 2021, are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions. Owners and operators of MSW landfills subject to this rule must comply with the following:

      (A) Reporting guidelines -- 40 CFR 62.16724;
      (B) Reporting Exemptions -- 
      1. Exemptions for reporting requirements for closed 	landfills -- 40 CFR 62.16711(g); and
      2. Exemptions for reporting requirements for legacy 	controlled landfills -- 40 CFR 62.16711(h); and
      (C) Recordkeeping guidelines -- 40 CFR 62.16726.
      
(5) 	Test Methods. The provisions of 40 CFR 62.16718, promulgated as of July 1, 2021, shall apply and are hereby incorporated by reference in the rule, as published by the U.S. Government Publishing Office available at https://bookstore.gpo.gov/ or for mail orders, print and fill out order form online and mail to: U.S. Government Publishing Office, PO Box 979050, St. Louis, MO 63197-9000. This rule does not incorporate any subsequent amendments or additions.

EPA Analysis:  The amendments to 10 CSR 10-6.310 reference 40 CFR Part 62 Subpart OOO instead of having the language explicitly laid out in the rule. This reference allows for flexibility in updating the state rule in response to future changes to federal requirements. 

This TSD does not include the redline for a section of language that was removed between Sections (2) and (3). The removed language was federal text from the prior emission guidelines that were not previously incorporated by reference. The redline language can be found on pages 100-131 of the MoDNR submittal document.

In the previous municipal solid waste landfill rule (40 CFR Part 60, Subpart WWW), an NMOC value calculated at greater than 50 Mg per year at MSW landfills with a design capacity greater than or equal to 2.5 million Mg and 2.5 million m[3] requires installation of a gas collection and control system (GCCS). The new rule, as per 40 CFR Part 62, Subpart OOO, requires installation of a GCCS for landfills of the same design capacity and an NMOC value of 34 Mg per year or greater. The amendment to 10 CSR 10-6.310 incorporates by reference the new NMOC value of 34 Mg per year and the design capacity does not change. 

The amendment as written establishes requirements equivalent to the federal rule. Therefore, EPA proposes to approve the rule revisions as meeting the requirements of CAA section 111(d).

CONCLUSION

The EPA's review of the material submitted indicates that the state has submitted the State section 111(d) Plan and has amended the state rules in accordance with the requirements of the Clean Air Act. Therefore, EPA proposed to approve the state's section 111(d) Plan and the revisions to state rules 10-5.490 and 10-6.310 as meeting the requirements of CAA section 111(d). Further, the rule revisions to 10-5.490 proposed for inclusion in the Missouri SIP will clarify language for subject municipal solid waste landfills in the St. Louis area. EPA is therefore proposing to approve 10-5.490 for inclusion in the Missouri SIP. 

Additionally, as noted in the associated notice of proposed rulemaking, the EPA Administrator continues to retain the following authorities that are not delegable to state agencies as described in 40 CFR 62.16710(b): Approval of alternative methods to determine the site-specific nonmethane organic compounds (NMOC) concentration or a site-specific methane generation rate constant (k); Alternative emission standards; Major alternatives to test methods (Major alternatives to test methods or to monitoring are modifications made to a federally enforceable test method or to a Federal monitoring requirement. These changes may involve the use of unproven technology or modified procedures or an entirely new methos.); and Waivers of recordkeeping.