1 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 1 5 POST OFFICE SQUARE, SUITE 100 BOSTON, MA 02109

- 3912

Memorandum

Date: July 15, 2016

Subject: Technical Support Document : Vermont SIP Revisions relating to N ew S ource R eview permitting and certain other requirements, submitted in 1993, 2011, and 2014

From: Donald Dahl Environmental Engineer

Thru: Ida E. McDonnell, Manager Air Permits, Toxics, and Ind oor Programs Unit

To: File

The following table provides EPA Region 1 ’s analysis of Vermont’s 1993, 2011, and 2014 SIP submittals and provides the agency’s rationale for concluding that the revision s to Vermont’s regulations , which EPA is approving in the associated federal register notice, are consistent with EPA’s new source review regulations codified at 40 CFR 51.1 60

- 166 , and with other applicable Clean Air Act requirements . The table below is organized by the State’s individual SIP revision requests submitted in 1993, 2011, and 2014.2 

### 1993 August 9, 1993 SIP Submittal

Revisions to Section 5

- 101 (Definitions) State Definition EPA Definition Action

" Federally Enforceable" means all limitations and conditions which are enforceable by the U.S. Environmental Protection Agency, whether contained in federal regulations, a state implementation plan, or construction or operating permits. 40 CFR 51.166(b)(17): Federally enforceable means all limitations and conditions which are enforceable by the Administrator, including those requirements developed pursuant to 40 CFR parts 60 and 61, requirements within any applicable State implementation plan, any approved pursuant to 40 CFR part 51, subpart I, including operating permits issued under an EPA

- approved program that is incorporated into the State implementation plan and expressly requires adherence to any permit issued under such program. permit requirements established pursuant to 40 CFR 52.21 or under regulations Approve : T he S tate’s definition is consistent with EPA’s definition.3 

### 2011 Submittal February 14, 2011

Revisions to Section 5

- 101 (Definitions) State Definition EPA Definition Action

“ Federal Land Manager ” means the Secretary of the department with authority over a Class I Federal area or his or her representative. 40 CFR 51.166(b)(24): Federal Land Manager means, with respect to any lands in the United States, the Secretary of the department with authority over such lands. Approve : T he S tate’s definition is consistent with EPA’s definition for use within the PSD permitting program

. T he S tate is required to involve the Federal Land Manager for projects impacting Class I areas. Revisions to Section 5

- 251 ( Control of Nitrogen Oxides Emissions ) State Regulation Action (1) No person shall discharge, or cause, allow or permit emissions of oxides of nitrogen, expressed as NO x , from any steam generating fuel burning equipment with a heat input capacity of 250 million BTU 's per hour or more in excess of:

(a) 0.36 grams per million calories heat input (0.20 pounds per million BTU) derived from gaseous fossil fuel

.
(b) 0.54 grams per million calories heat input (0.30 pounds per million BTU) derived from liquid fossil fuel

.
(c) 1.26 grams per million calories heat input (0.70 pounds per million BTU) derived from solid fossil fuel (except lignite or a fossil fuel containing 25 percent by weight, or more of coal refuse ). Approve: Vermont changed the applicability of this section from “fuel burning equipment with a heat input capacity of 250 MMBtu/hr or more” to “steam generating fuel burning equipment with a heat input capacity of 250 MMBtu/hr or more.” The term “Fuel burning equipment” is defined in the SIP as “ any furna ce, boiler, and/or apparatus, used in the process of burning fuel for the primary purpose of producing heat or power. ” This definition would include process heaters that use a fluid other than water. In a letter dated July 13, 2016, Vermont informed EPA th at at this time Vermont does not have any fuel burning equipment above 250 MMBtu/hr that is not using water as the heat transfer fluid. In addition, a ny new fuel burning equipment with a heat input capacity of 250 MMBtu/hr or more , regardless of whether th e heat transfer fluid is water or not, would be subject to Vermont’s PSD program and be required to install pollution control equipment which meets the definition of “Most Stringent Emission Rate” (equivalent or better than EPA’s definition of best availab le4

(2) Reasonably available control technology for large stationary

sources.

(a) The owner or operator of any stationary source that has allowable emissions of one hundred (100) tons per year or more of nitrogen oxides shall install, maintain and

use reasonably available control technology , approved by the Secr etary , to limit the discharge of nitrogen oxides from the source by commencement of operation.

(b) Any source that becomes or is currently subject to the provisions of this subsection by exceeding the applicability threshold in paragraph ( 2 )(a) of this subsection shall remain subject to these provisions even if its emissions later fall below the applicability threshold.

(c) E xemptions. Any NO x emission unit required to meet the most stringent emission rate (MSER) in a construction permit co ntaining specific emission limits is exempt from the requirements of Section 5

- 251( 2 ). control technology in 40 CFR 51.166) for SO 2 and NO x emissions. This

case

- by

- case analysis will result in permitted emission limits below the requirements of Sections 5

- 251(1) and 5

- 252.

Revisions to Section 5

- 25 2 ( Control of Sulfur Dioxide Emissions ) No person shall discharge, or cause, allow or permit emissions of sulfur dioxide from any steam generating fuel burning equipment with a heat input capacity of 250 million BTU's per hour or more in excess of:

(a) 1.4 grams per million calories heat input (0.80 pounds per million BTU) derived from liquid fossil fuel

.
(b) 2.2 grams per million calories heat input (1.2 pounds per million BTU) derived from solid fossil fuel

. Approve: The revisions to this section are approvable under the same rational artic ulated above for the control of nitrogen oxides in Section 5

- 251.5 Revisions to Section 5

- 401 ( Classification of Air Contaminant Sources ) State Regulation Current SIP Regulation Action 5

- 401(2) Hot

- mix asphalt plants Asphalt hot

- mix batching plants Approve : S imple name change

. Revisions to 5

- 402 ( Written R eports When Requested ) State Regulation EPA Regulation Action 5

- 402: The Air Pollution Control Officer may at any time require written reports from the person operating or responsible for any proposed or existing air contaminant source, which reports shall contain information concerning location, siting, size and height of contaminant outlets, processes employed, pertinent process and material flow, fuels used, nature and amount and time periods or durations of emissions and such other information as may be relevant to the air pollution potential of the source. These reports shall also include the results of such source testing as may be required under Section 5

- 404 herein. Various provisions requiring submission of information for purposes of issuing or denying preconstruction permits. Approve: Revised language clarifies the universe of sources from which the state has the authority to require reports.

Revisions to Section 5

- 406 ( Required Air Modeling ) The Air Pollution Control Officer may require the owner or operator of any proposed air contaminant source subject to review pursuant to Sections 5

- 501 or 5

- 503 herein to conduct diffusion or other air quality mod eling and to submit an air quality impact evaluation to demonstrate that operation of the proposed source as described to the Air Pollution Control Officer will not directly or indirectly result in a violation of any ambient air quality standard, interfere with the attainment of any ambient air quality standard, or violate any applicable prevention of significant deterioration increment (Table 2). (2) For proposed stationary sources, the appropriate air quality modeling techniques shall be determined on a case

- by

- case basis in accordance with procedures established by the Air Pollution Control Officer. 40 CFR 51.160(f)(1) and 51.166( l ) Approve : T h is SIP revision

, when combined with the revisions Vermont subsequently promulgated to Section 5

- 406 , and which was included in the State’s 2014 SIP submittal

, is consistent with federal requirements. See later discussion of Section 5

- 406 under the section relating to the State’s 2014 SIP submittal.6 Revisions to Section 5

- 501 (R eview of Construction or Modifica tion of Air Contaminant Sources ) (1) No person shall cause, suffer, allow or permit the new construction, installation or modification of any stationary source classified as an air contaminant source under Section 5

- 401 herein, unless he or she first subm its a complete application to and obtains a permit from the Secretary. Approve : T he r evision relies on the term stationary source which is defined in the SIP as

“ any structure, building, facility, equipment, installation, or operation (or combination thereof) which emits or may emit any air contaminant, which is located on one or more contiguous or adjacent properties and which is owned or operated by the same person (or by persons under common control). ” Definition of stationary source is equivalent to 40 CFR 51.166(b)( 6). (4) The S ecretary shall issue a permit if the S ecretary determines that the proposed construction, installation, or modification of an air contaminant source will be in compliance with all requirements of these regulations and Vermont statutes at Title 10, chapter 23. If the S ecretary determines that the proposed construction, installation or modification will not be in compliance with all requirements of these regulations and Vermont statutes at Title 10, chapter 23, the S ecret ary shall deny the permit and shall notify the applicant in writing of the reasons for the denial. 51.160 (a) Each plan must set forth legally enforceable procedures that enable the State or local agency to determine whether the construction or modificatio n of a facility, building, structure or installation, or combination of these will result in

— (1) A violation of applicable portions of the control strategy; or (2) Interference with attainment or maintenance of a national standard in the State in which th e proposed source (or Approve : Section 5

- 406 gives the S tate authority
to require a source to demonstrate it will not

, violate applicable portions of the control strategy, violate a NAAQS, interfere with maintenance , or violate a PSD increment

, using air dispersion modeling.7 modification) is located or in a neighboring State. (b) Such procedures must include means by which the State or local agency responsible for final decision making on an application for approval to construct or modify will prevent suc h construction or modification if

— (1) It will result in a violation of applicable portions of the control strategy; or (2) It will interfere with the attainment or maintenance of a national standard. The St ate addresses the federal requirement that model ing be conducted in accordance with Appendix W i n the State’s 2014 SIP submittal discussed later in this TSD

.

(7) Upon making a determination to issue a draft permit under this section for a major stationary source, major modification, or other source i n the discretion of the Secretary, opportunity for public participation shall be provided as follows:

* * *

(c) If required by 40 C.F.R. § 51.166(q)(2)(iv), the Secretary will send a copy of the notice to the applicant, EPA, and to officials and agencies having cognizance over the location where the proposed construction would occur. 40 CFR 51.166(q)(2)(iv) Approve : T his notification obligation required of the State is an additional public participation provision that supplement the public notification provisions currently in the SIP and codified as Sections 5

- 501(4)(a)

- (d)

. The new section 5

- 501(7)(c) will not be replacing , but will only be supplementing, the existing SIP approved public participation requirements for m ajor NSR permits.8 Revisions to Section 5

- 502 ( Major Stationary Sources And Major Modifications ) (2) Prohibition No person shall initiate construction of any major stationary source or major modification until the applicable requirements of this section have been complied with and a p ermit approving construction has been issued in accordance with Section 5

- 501 herein. 40 CFR 51.166(a)(7) (iii) Approve : Vermont’s language is consistent with federal requirements.

(4) Air Quality Impact Evaluation

(a) A source or modification subject to this section with respect to any air contaminant other than volatile organic compounds or greenhouse

gases , shall submit to the Secretary an air quality impact evaluation at the time it applies for approval to construct under Section 5

- 501 herei n. 40 CFR 51.166(k) Approve : A lthough the provision improperly excludes VOCs

, Vermont corrected this error in revised regulations submitted with its 2 014 SIP submittal as explained later in this TSD . With the revision made in 2014, Vermont’s language is no w consistent with federal requirements. (b) The evaluation shall demonstrate that the increase in allowable emissions will not cause violations of any applicable ambient air quality standard in any area, and will not significantly contribute to a violatio n of any applicable ambient air quality standard in a nonattainment area for the above air contaminants . A source or modification will be considered to significantly contribute to a violation of any ambient air quality standard for the above air contaminan ts if the increase in the allowable emissions from the source

or modification will cause any increase in ambient concentrations of the above air contaminants in the nonattainment area in excess of any of the levels of significant impact shown in Table 3 herein. If a source

or modification will significantly contribute to such a violation, the 40 CFR 51.166(k)(1)(i) and 51.165(b)(2): Approve : This SIP revision, when combined with the revisions Vermont subsequently promulgated to Section 5

- 502(4)(b), and which was included in the State’s 2014 SIP submittal, is consistent with federal requirements. See later9

evaluation shall demonstrate that the source or modification will comply with the requirements of paragraph (6) herein. discussion of Section 5

- 502(4)(b) under the section relating to the State’s 2014 SIP submittal. (e) Any air quality impact evaluation or modeling required by this section shall be prepared in accordance with procedur es acceptable to the Secretary and with Section 5

- 406 of these regulations. The evaluation shall exclude the effect of that portion of the height of any stack which exceeds good engineering practice and the effect of any other dispersion technique. 40 CFR 51.166( l ) Approve : T he revision to Section 5

- 406 of the State’s regulations, submitted by the State with its 2014 SIP submittal, requires modeling to be conducted in accordance with 40 CFR part 51, Appendix W , and therefore meets federal requirements

. (6) (b) Regardless of whether a source or modification is subject to the requirements of paragraph (6)(a) of this section, the Secretary shall not issue a permit approving construction of any source or modification of nitrogen oxides or volatile organic compou nds (VOCs) subject to this section and meeting the federal definition of major stationary source or major modification contained in 40 CFR Part 51.165 as applicable to the Ozone Transport Region unless, prior to issuance of such permit, the owner or operat or of said source shall:

(i) Secure legally binding offsetting emission reductions (not otherwise required by law) of nitrogen oxides or VOCs , as applicable, from existing sources;

(ii) Obtain an offset ratio of a minimum of 1.15:1; and 40 CFR 51.165 Approve : Vermont’s revised language makes it clear that nonattainment new source review applies to major sources of NOx and VOC in relation to

ozone , because Vermont is located in the Ozone Transport R egion. The 2014 SIP submittal made a slight revision to this pr ovision by replacing “Part” with

“ § ” when citing 40 CFR 51.165

.10

(iii) Certify that all existing sources of the source owner located in the state are subject to emissions limitations and are in compliance, or on an enforceable schedule for compliance with all applicable emissions limitations and standards. (8) Ambient Air Quality Monitoring

(b) Ambient monitoring data shall be based on sampling conducted for a time period of up to one year immediately preceding submission of any application for approval to construct such a source or modification

. Ambient monitoring data collected for a time period of less than one year or for a time period other than immediately preceding submission of any such application may be acceptable if such data is ad equate for determining whether the source or modification will cause a violation of any applicable ambient air quality standard or consume more than the remaining available PSD increment. 40 CFR 51.166(m)(1)(b)(iii) and (iv) Approve : T he State’s provisio n submitted in the State’s 2011 SIP submission, when combined with the revisions to the provision Vermont subsequently made and submitted to EPA in 2014, is consistent with EPA regulations.11 

### 2014 July 25, 2014 SIP Submittal

Revisions to Section 5

- 101 (Definitions) State Definition EPA Regulation Action

“ Municipal Waste Combustor Acid Gases (measured as sulfur dioxide and hydrogen chloride)” means all acid gases emitted in the exhaust gases from MWC units including, but not limited to, sulfur dioxide and hydrogen chloride gases

. 40 CFR 51.166(b)(23)(i): Municipal waste combustor acid gases (measured as sulfur dioxide and hydrogen chloride): 36 megagrams per year (40 tons per year)

40 CFR 60.51(a): MWC acid gases means all acid gases emitted in the exhaust gases from MWC units including, but not limited to, sulfur dioxide and hydrogen chloride gases. Approve : Vermont’s language is consistent with federal regulations.

“ Municipal Waste Combustor Metals (measured as particulate matter)” means me tals and metal compounds emitted in the exhaust gases from MWC units

. 40 40 CFR 51.166(b)(23)(i): Municipal waste combustor metals (measured as particulate matter): 14 megagrams per year (15 tons per year)

40 CFR 60.51(a): MWC metals means metals and metal compounds emitted in the exhaust gases from MWC units. Approve : Vermont’s language is consistent with federal regulations.

“ Municipal Waste Combustor Organics (measured as total tetra

- through octa

- chlorinated dibenzo

- p

dioxins and dibenzofurans)” means organic compounds emitted in the exhaust gases from MWC units and includes total tetra

- through octa

chlorinated dibenzo

- p

- dioxins and dibenzofurans

. 40 CFR 51.166(b)(23)(i): Municipal waste combustor acid gases (measured as sulfu r dioxide and hydrogen chloride): 36 megagrams per year (40 tons per year)

40 CFR 60.51(a): MWC organics means organic compounds emitted in the exhaust gases from MWC units and includes total tetra

- through octa

- chlorinated dibenzo

- p

- dioxins and dibenzofu rans. Approve : Vermont’s language is consistent with federal regulations.

“ Municipal Solid Waste Landfill Emissions (measured as nonmethane organic compounds)” means gas generated by the decomposition of organic waste deposited in an MSW landfill or 40 CFR 51.166(b)(23)(i): Municipal solid waste landfill emissions (measured as nonmethane organic compounds): 45 megagrams per year (50 tons per year) Approve : Vermont’s language is consistent with federal regulations.12

deriv ed from the evolution of organic compounds in the waste. 40 CFR 60.751: Municipal solid waste landfill e missions or MSW landfill emissions means gas generated by the decomposition of organic waste deposited in an MSW landfill or derived from the evolution of organic compounds in the
waste.

“ Particulate Matter ” means any airborne finely divided solid or liquid material with an aerodynamic diameter smaller than one

- hundred (100) micrometers. 40 CFR part 51 Approve : Vermont’s language is consistent with federal regulations.

“ Part iculate Matter Emissions ” means all finely divided solid or liquid material, other than uncombined water, emitted to the ambient air as measured by applicable reference methods, or an equivalent or alternative method, specified in 40 C.F.R. Chapter 1. Emi ssions shall include gaseous emissions from a source or activity which condense to form particulate matter at ambient temperatures. 40 CFR 51.50: Particulate matter (PM) is a criteria air pollutant. For the purpose of this subpart, the following definitions apply: (1) Filterable PM 2.5 or Filterable PM 10 : Particles that are directly emitted by a source as a solid or liquid at stack or release conditions and captured on the filter of a stack test train. Filterable PM 2.5 is particulate matter with an aerodynamic diameter equal to or less than 2.5 micrometers. Filterable PM 10 is particulate matter with an aerodynamic diameter equal to or less than 10 micrometers. (2) Condensab le PM: Material that is vapor phase at stack conditions, but which condenses and/or reacts upon cooling and dilution in the ambient air to form solid or liquid PM immediately after discharge from the stack. Note that all condensable PM, if present from a s ource, is typically in the PM 2.5 size fraction and, therefore, all of it is a component of both primary PM 2.5 and primary PM 10. (3) Primary PM

2.5 : The sum of filterable PM 2.5 and condensable PM. (4) Primary PM 10 : The sum of filterable PM 10 and condensable PM. Approve : Vermont’s language is consistent with federal regulations.13 (5) Secondary PM: Particles that form or grow in mass through chemical reactions in the ambient air well after dilution and condensation have occurred. Secondary PM is usually formed at some distance downwind from the source. Secondary PM should not be reported in the emission inventory and is not covered by this subpart. “PM 10 ” means particulate matter with an aerodynamic diameter less than or equal to a nominal ten (10) micrometers as measured by a reference method based on appendix J of 40 C.F.R. Part 50 and designated in accordance with 40 C.F.R. Part 53, or by an equivalent method designated in accordance with 40 C.F.R. Part 53. 40 CFR part 51 Approve : Vermont’s language is consistent with federal regulations.

“PM 10 Emissions ” means finely divided solid or liquid material, with an aerodynamic diameter less than or equal to a nominal ten (10) micrometers emitted to the ambient air as measured by an applicable reference method, or an equivalent or alternative method, specified in 40 C.F.R. Chapter 1. Emissions shall include gaseous emissions from a source or activity which c ondense to form particulate matter at ambient temperatures. 40 CFR part 51 Approve: Vermont’s language is consistent with federal regulations.

“PM 2.5 ” means particulate matter with an aerodynamic diameter less than or equal to a nominal two

- and

- a

- half (2.5) micrometers as measured by a reference method based on Appendix L of 40 C.F.R. Part 50 and designated in accordance with 40 C.F.R. Part 53, or by an equiv alent method designated in accordance with 40 C.F.R. Part 53. 40 CFR part 51 Approve: Vermont’s language is consistent with federal regulations.

“PM 2.5 direct emissions ” means finely divided solid or liquid material, with an aerodynamic diameter less than or equal to a nominal two

- and

- a

- half (2.5) micrometers emitted to the ambient air as measured 40 CFR part 51 Approve: Vermont’s language is consistent with federal regulations.14

by an applicable reference method, or an equivalent or alternative method, specifi ed in 40 C.F.R. Chapter 1. Emissions shall include gaseous emissions from a source or activity which condense to form particulate matter at ambient temperatures. It does not include emissions of other gaseous precursors which may subsequently contribute t o formation of secondary PM 2.5 particles through chemical reactions.15

Air Contaminant Tons Per Year

Carbon monoxide 50 Nitrogen oxides 40

Sulfur dioxide 40

Particulate matter emissions 25

PM 10 emissions 15

PM 2.5 1

PM 2.5 direct emissions 10 Sulfur dioxide 40 Nitrogen oxides 40
Volatile organic compounds(VOC) 40

Lead 0.6

Fluorides 3

Sulfuric acid mist 7 Hydrogen sulfide (H 2 S) 10

Total reduced sulfur (including H 2 S) 10

Reduced sulfur compounds (including H 2 S) 10

Municipal waste combustor organics (measured as total tetra

- through octa

chlorinated dibenzo

- p

- dioxins and 3.5 × 10

- 6 40 CFR 51.166(b)(23) Approve : The highlighted text is the revised text contained in the State’s 2014 SIP revision and is consistent with EPA’s regulations.16

dibenzofurans)
Municipal waste combustor metals (measured

as particulate matter) 15

Municipal waste combustor acid gases (measured as sulfur dioxide and hydrogen chloride) 40

Municipal solid waste landfill
emissions (measured as nonmethane organic compounds) 50

Greenhouse gases 1. 2

1 For PM 2.5 , significant means either 10 tons per year or more of direct PM 2.5 emissions, 40 tons per year or more of sulfur dioxide emissions or 40 tons per year or more of nitrogen oxides emissions.

2 For greenhouse gases , “significant” means a rate of emissions for total greenhouse ga ses , on a carbon dioxide equivalent (CO 2 e) basis, that (1) is subject to regulation at that source or modification, and (2) would equal or exceed the significance level established by EPA.17 Revision to Section 5

- 253.20 ( Other Sources That Emit Volatile Organic Compounds ) Revision to the State Regulation EPA Regulation Action Vermont requested removing the exemption for wood coating from applicability section in Section 5

- 253.20(a)(3)

. Approve : This revision means that wood coating operations are now subject to the section limiting emissions from miscellaneous VOC sources in the Vermont SIP , and is consistent with Clean Air Act and State requirements for controlling VOC emissions

.18 Revisions to Subchapter III ( Ambient Air Quality Standards ) State Regulation EPA Regulation Action 5

- 301 SCOPE

The ambient air quality standards contained in this subchapter are based on national ambient air quality standards , with the exception of sulfates which are a state standard only. The primary standards define levels of air quality judged adequate to protect the public health. The secondary standards define levels of air quality judged adequate to protect the public welfare, to prevent injury to animal or plant life or property, and to prevent unreasonable interference wi th the enjoyment of life or property. 40 CFR Part 50 Approve : Vermont’s language is consistent with federal regulations.

5

- 302 SULFUR OXIDES (SULFUR DIOXIDE)

The ambient air quality standards for sulfur oxides, measured as sulfur dioxide in accordance with 40 C.F.R. Part 50, are:

75 parts per billion (ppb), with a 1

- hour averaging time and a form of the 99th percentile of 1

- hour daily maximum concentrations, averaged over 3 years (Primary St andard).

0.5 parts per million (ppm), with a 3

- hour averaging time and a form that is not to be exceeded more than once per year (Secondary Standard). 40 CFR Part 50 Approve: Vermont’s language is consistent with federal regulations.

5

- 303 RESERVED19

5

- 304 PARTICULATE MATTER PM 2.5

The ambient air quality standards for particulate matter PM 2.5 , measured in accordance with 40 C.F.R. Part 50, are:

35 micrograms per cubic meter (μg/m 3 ), with a 24

- hour averaging time and a form of the 98 th percentile, averaged over 3 years (Primary and Secondary Standard).

12 micrograms per cubic meter (μg/m 3 ), with an annual averaging time and a form of the annual mean averaged over 3 years (Primary Standard).

15 micrograms per cubic meter (μg/m 3 ), with an annual averaging time and a form of the annual mean averaged over 3 years (Secondary Standard). 40 CFR Part 50 Approve: Vermont’s language is consistent with federal regulations.

5

- 305 RESERVED20

5

- 306 PARTICULATE MATTER PM 10

The ambient air quality standards for particulate matter PM 10 , measured in accordance with 40 C.F.R. Part 50, are:

150 micrograms per cubic meter (μg/m 3 ), with a 24

- hour averaging time and a form not to be exceeded more than once per year on average over 3 years (Primary and Secondary Standard). 40 CFR Part 50 Approve: Vermont’s language is consistent with federal regulations.

5

- 307 CARBON MONOXIDE

The ambient air quality standards for carbon monoxide, measured in accordance with 40 C.F.R. Part 50, are:

35 parts per million (ppm), with a 1

- hour averaging time and a form not to be exceeded more than once per year (Primary Standard).

9 parts per million (ppm), with an 8

- hour averaging time and a form not to be exceeded more than once per year (Primary Standard). 4 0 CFR Part 50 Approve: Vermont’s language is consistent with federal regulations.21

5

- 308 OZONE

The ambient air quality standards for ozone, measured in accordance with 40 C.F.R. Part 50, are:

0.075 parts per million (ppm), with an 8

- hour averaging tim e and a form of the annual fourth

- highest daily maximum 8

- hour concentration, averaged over 3 years (Primary and Secondary Standard). 40 CFR Part 50 Approve: Vermont’s language is consistent with the federal 2008 ozone standard. Because the S tate last revised this section of its rules in 2014, the State was unable at that time to address the 2015 ozone standard , which had not yet been promulgated by EPA . Therefore, while the provision is approvable because the 2008 ozone standard has not been revoked by EPA, the approval i s not suggesting the S tate’s provision is adequate to reflect the federal 2015 ozone standard. The State is expected to address this new ozone standard in a subsequent submittal to EPA.22

5

- 309 NITROGEN DIOXIDE

The ambient air quality standards for nitrogen dioxide, measured in accordance with 40 C.F.R. Part 50, are: 100 parts per billion (ppb), with a 1 hour averaging time, and a form of the 98 th percentile, averaged over 3 years (Primary Standard).

53 parts per billion (ppb), with a n annual averaging time, and a form of the annual mean (Primary and Secondary Standard). 40 CFR Part 50 Approve: Vermont’s language is consistent with federal regulations.

5

- 310 LEAD

The ambient air quality standards for lead and its compounds, measured in accordance with 40 C.F.R. Part 50, are: 0.15 micrograms per cubic meter (μg/m 3 ), with a rolling 3

- month average averaging time and a not

- to

- be

- exceeded form, evaluated over a 3

- year period (Primary and Secondary St andard). 40 CFR Part 50 Approve: Vermont’s language is consistent with federal regulations.

Revisions to Section 5

- 406 Required Air Modeling State Regulation EPA Regulation Action ( 1) The Air Pollution Control Officer may require the owner or operator of any proposed air contaminant source subject to review pursuant to Section 5

- 501 herein to conduct dispersion or other air quality modeling and to submit an air quality impact evaluation to demonstrate that operation of the proposed source as described to the Air Pollution Control Officer will not directly or indirectly result in a violation of any ambient air quality standard , interfere with the attainment of any ambient air quality standard , or violate any applicable p revention of significant deterioration increment ( Table 2 ).

(2) For proposed stationary sources , the appropriate air quality modeling techniques shall be determined on a case

- by

- case basis in accordance with procedures established in 40 C.F.R. Part 51 App endix W. 40 CFR 51.160(f) and 51.166( l ). Approve : Vermont’s language is consistent with federal regulations.23 Revisions to Section 5

- 501 (Review of New Air Contaminant Sources) State Regulation Existing SIP Approved Language Action

(5) Section 5

- 501(5): If allowable emission increases of any air contaminant from a source subject to this section will cause or contribute to a violation of any ambient air quality standard or cause or contribute to a violation of any applicable prevention of significant deterioration increment ( Table 2 ), or if such source is located within 10 kilometers of a Class I area and will have an impact on such Class I area of equal to or greater than 1 ug/m 3 (24

- hour average) for any air contaminant , such air contaminant shall be considered significant and such source will be treated as a major stationary source or a major modification for the purposes of its review under these regulations. With regard to a modification of a source, the al lowable emission increases mean the difference between the source's actual emissions before the modification and its allowable emissions after the modification

. (5) If allowable emission increases of any air contaminant from a source subject to this secti on will cause or contribute to a violation of any ambient air quality standard or cause or contribute to a violation of any applicable prevention of significant deterioration increment (Table 2), or will impact on any Class I area, such source shall achiev e MSER with respect to any such contaminant and will be treated as a major stationary source or a major modification for the purposes of its review under these regulations. With regard to a modification of a source, the allowable emission increases mean th e difference between the source's actual emissions before the modification and its allowable emissions after the modification. Approve : This section of Vermont’s regulations require sources that would only be subject to minor new source review to obtain a major new source review if the State determines that the impacts from the new source meet the criteria specified in section 5

- 501(5). There is no corresponding federal regulation, but this provision is approvable because States are permitted to be more stringent than the federal regulations.24 State Regulation EPA Regulation Action (7) Upon making a determination to issue a draft permit under this section f or a major stationary source, major modification , or other source in the discretion of the Secretary , opportunity for public participation shall be provided as follows:

* * *

(c) If required b y 40 C.F.R. §51.166(q)(2)(iv), the Secretary will send a copy of the notice to the applicant, the EPA Regional Administrator, and to officials and agencies having cognizance over the location where the proposed construction would occur, including: any othe r State or local air pollution control agencies, the chief executives of the city or town and county where the source would be located, any comprehensive regional land use planning agency, and any State, Federal Land Manager, or Indian Governing body whose lands may be affected by emissions from the source or modification. 40 CFR 51.166 (q)(2) (iv) : Approve : State language is consistent with EPA’s regulations. See earlier discussion in this TSD regarding how this provision meshes with already existing SIP

approved public participation requirements for major

sources.

Revisions to Section 5

- 502 ( Major Stationary Source and Major Modification ) State Regulation EPA Regulation Action Section 5

- 502(4)(a) Air Quality Impact Evaluation

(a) A source or modification subject to this section with respect to any air contaminant other than greenhouse gases , shall submit to the Secretary an air quality impact evaluation at the time it applies for approval to construct under Section 5

- 501 herein. 40 CFR 51.166(k) Approve : State language is consistent with EPA’s regulations. See earlier discussion in this TSD regarding the same provision submitted earlier by the State to EPA. The earlier exclusion of VOCs from this provision is corrected in this version of the provision. Section 5

- 502(4)(b): Ambient Air Quality Standards review: The evaluation shall demonstrate that the increase in allowable emissions will not cause a violation of any applicable ambient air quality standard in any area, and will not sign ificantly contribute to a violation of any applicable ambient air quality 40 CFR 51.166( k) and 51.165(b) Approve: State language is consistent with EPA’s regulations. See earlier discussion in this TSD25

standard in any area that does not or would not meet the applicable ambient air quality standard for the above air contaminants . A source or modification will be considered to signif

icantly contribute to, a violation of any ambient air quality standard for the above air contaminants if the increase in the allowable emissions from the source or modification will cause an increase in ambient concentrations of the above air contaminants in any area that does not or would not meet the applicable ambient air quality standard in excess of any of the levels of significant impact shown in Table 3 herein. If a source or modification will significantly contribute to such a violation, the evaluat ion shall demonstrate that the source or modification will comply with the requirements of paragraph (6) herein. regarding the same provision submitted earlier by the State to EPA. This section in the 2011 SIP submittal was applicable to a source if the source’s emissions significantly contributed to a violation in a designated nonattainment areas. In 2014, the State revised its rule to include any area that is violating a standard, whether or not that area has been formerly designated a nonattainment area by EPA. Section 5

- 502(4) (e) Class I Federal Area review: The evaluation shall demonstrate that the increase in allowable emissions will not cause an adverse impact on visibility or any other Air Quality Related Value in any Class I Federal area

. 40 CFR 51.166(p) Approve : State l anguage is consistent with EPA’s regulations.

Section 5

- 502(6)(b) 40 CFR 51.165 Approve: State language is consistent with EPA’s regulations. See earlier discussion in this TSD regarding the same provision submitted earlier by the State to EPA. The revision Vermont made to this26 provision in 2014 replaced the word “part” with § when ci ting 40 CFR § 51.166. Section 5

- 502(8)(b): Ambient monitoring data shall be based on sampling conducted for a time period of at least one year immediately preceding submission of any application for approval to construct such a source or modification . Ambi ent monitoring data collected for a time period of less than one year, but not less than four (4) months, or for a time period other than immediately preceding submission of any such application may be acceptable if such data is adequate for determining wh ether the source or modification will cause a violation of any applicable ambient air quality standard or consume more than the remaining available PSD increment. 40 CFR 51.166(m)(1)(iv) Approve: State language is consistent with EPA’s regulations. See earlier discussion in this TSD regarding the same provision submitted earlier by the State to EPA. The revisions Vermont made to this provision in 2014 clarif

y that a minimum of 4 months of monitoring data is required in all circumstances

.