**----·- ~**  - --**--- --** **-- ---** **-- --** **--- --** **------- ---** **~**

UNITED STATES ENVIRONMENTAL PROTECTION AGE NCY R EGIO N 1

July 19, 2012 Marc Cone 5 POST O FFICE SQUARE SUITE 100 BOSTON MA 02109-3912

Bureau of Air Quality Control Department ofEnvironmental Protection 17 State House Station Augusta, ME 04333 Dear Mr. Cone: Thank you for the opportunity to review the Maine Department ofEnvironmental Protection ' s (DEP) proposed revisions to Chapter 100, Definitions, Chapter 115, Major and Minor Air Emission License Regulations and Chapter 140, Part 70 Air Emissions License Regulations. Our comments are attached to this letter. The revisions include changes to implement the current federal New Source Review (NSR) applicability test provisions such as the actual-to-future actual applicability test and the Plantwide Applicability Limits, EPA's NSR implementation requirements for Particulate Matter with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers (PM2
.s), federal Greenhouse Gases (GHG) permitting requirements and other changes to the state permitting program. Once the public comment period ends , EPA understands the DEP will respond to all comments made by EPA and other reviewers and submit the revised regulation to EPA as formal revision to its State Implementation Plan (SIP) rules
. Again, thank you for the opportunity to review the proposed revisions to your state NSR permitting regulations
. Ifyou have any questions , please call Brendan McCahill at (617) 918-1652. Sincerely,

Ida E. McDonnell, Manager Air Permits, Toxics and Indoor Programs Unit Enclosure

Toll Free • 1 888·372-7341 Intern.it Address (URL • http '/.WW epa gov regonl**Aecycle~ecyclable** • Printed Wllh Vegetabl e Oii Baud In k• on Rtcycled Paper (Minimum JO•. Postconsumer

### Enclosure EPA'S COMMENTS TO MAINE'S PROPOSED REVISIONS TO CHAPTER 100, "DEFINITIONS," CHAPTER 115, "MAJOR AND MINOR AIR EMISSION LICENSE REGULATIONS" AND CHAPTER 140, "PART 70 AIR EMISSIONS LICENSE REGULATIONS" DATED JUNE 20, 2012

1. 

### General Comment: EPA notes the SIP-approved nonttainment NSR plan requirements at 40 CFR 51.165(a)(2)(ii) states that each plan shall use the specific applicability provisions ofparagraphs (a)(2)(ii)(A) through (F) ofthe section. Deviations from these provisions will be approved only ifthe state specifically demonstrates that the submitted provisions are more stringent than or at least as stringent in all respects as the corresponding provisions in paragraphs (a)(2)(ii)(A) through (F) ofthe section. The federal SIP-approved Prevention of Significant Deterioration (PSD) plan requirements contain a similar provision at 40 CFR 5l. l 66(a)(7)(iv)
. Specifically, EPA identified several revisions in the state 's major NSR permitting applicability requirements that deviate from the federal requirements. 

### Ifthe DEP retains those revisions , the DEP will need to submit a demonstration as part ofits SIP-approved submittal showing how the use ofits revised nonattainment NSR and PSD program applicability procedures are as stringent in all respects as the corresponding federal applicability requirements. The DEP may avoid the need for a demonstration by incorporating the federal applicability requirements without revision into its regulations
. 

### Chapter I00: Definitions 2
. Chapter 100
.28. C02 

### equivalent emissions (C02e): EPA's letter to the DEP dated November 29, 2010 advised the DEP to add the following phrase "as it may be revised by EPA from time to time" or, alternatively, " as of [date]," to avoid confusion ifTable A-1 (Global Warming Potentials) to subpart A of40 C.F.R. part 89 (Mandatory Greenhouse Gas Reporting) is modified by EPA at a later date. EPA recommends the DEP revise this provision using one ofthese options. 

### 3. Chapter 100.82. Major Modification:
a. 

### 100.82 A: The DEP's provision at 100.82.A is not consistent with the federal definition for " Major Modification" and does not include the two part test provided 

### in the federal definition. As described at 40 CFR 5 l. l 66(a)(7)(iv)(a) under the federal requirements for SIP-approved PSD program, a project is a major modification ifit is physical change or change 

### in the method ofoperation that causes two different types ofemission increases: (1) a significant emissions 

### 1increase ofa regulated pollutant and (2) a significant net emissions increase of that pollutant from the major stationary source.



### · In the first step, ifthe emission increase from the project does not exceed the

significance level for a given pollutant, the project is not a major modification. 

### If the emission increase from the project exceeds the emission threshold for a given pollutant, all other contemporaneous emission increases and decreases from the source for that pollutant are determined. 

### Ifthe sum ofemissions from the project and the contemporaneous emission increases and decreases from the source exceed the significance level for a given pollutant, than the project is a major modification for that pollutant. The DEP's definition of "major modification" occurs ifa modification results in a " significant emission increase. " Since the DEP ' s definition ofsignificant emission increase means a major modification which results in any " net emission increase" ofa regulated pollutant, the DEP's definition implements only the second part ofthe federal requirements two part test. This makes the DEP's definition more stringent than the federal definition. The following example illustrates how the DEP's definition differs from the federal definition. Three years ago, a major stationary source installs a device with a potential emission increase of 

### 10 tons per year (tpy) ofsulfur dioxide (S0 2). The source intends to install a new device with a potential increase of 35 tpy of S02• The significant emission increase threshold for S02 is 40 tpy . Under the federal definition, the new device results in a significant emission increase of 35 tpy . Since this is below 40 tpy, the new device does not result in a significant emission increase (the l st part ofthe two part test). The device is not a major modification. Maine ' s definition is based on significant net emission increase only, the new device results in a significant net emission increase at the major stationary sources of45 tpy (35 tpy 

### + 10 tpy)
. The new device is a major modification. b. Chapter 100.82.B : Chapter 100.82.B includes two additional definitions for "major modification." ChapterI 00.82.B (1) defines a major modification as an increase in the source ' s potential to emit by significant emissions which corresponds to the major stationary source thresholds in EPA's regulations. I00.82.B (2) defines a major modification as an increase in actual emissions by significant emissions from a physical or operational change at a minor stationary source. Both provisions describe scenarios EPA would consider "Major Stationary Sources ." EPA recommends the DEP remove these provisions from the definition of"Major modification ." Jn addition, the DEP 's regulation does not include a definition of "major stationary source." EPA recommends the DEP include a definition of"major stationary source" to its regulations that is consistent with t he federal definition
.
2

### 4. Chapter 100.92. Modification or Modified Source: Chapter 100
.92
.C implies that the replacement ofa pollution control apparatus at steam electrical utility generators or other sources shall not be considered physical changes or changes in the method ofoperation. Federal regulations do not provide for any such consideration
. EPA recommends the DEP remove this provision. 

### 5
. Chapter 100.94. Net Emission Increase:
a. EPA understands the DEP intends to implement the federal NSR requirements revised as of December 31, 2001. Under the federal requirements for SIPapproved PSD programs at 40 CFR 51
. 166, the federal definition for " net emissions increase" at 40 CFR 5 l
. 166(b)(3) refers to a number ofdifferent procedures for calculating a significant emission increase for different types of projects (e.g. , projects involving existing emission units, projects involving new existing units). These procedures are described in 40 CFR 5 l
.I66(a)(7)(iv). The DEP should include the procedures into Chapter 115. l, Applicability, of Chapter 115 , 

### Major and Minor Source Air Emission License Regulations permitting regulations. The federal requirements for SIP-approved nonattairunent NSR programs contain similar procedures for calculating significant emission increases at 40 CFR 5 l
.I65 (a) (2)(ii)
. b. The DEP's definition of "net emission increase" should state that an emissions increase or decrease of S02 , particulate matter (PM) and nitrogen oxides 

### (NOx) that occurs before the applicable minor source baseline date is creditable only ifit is required to be considered in calculating the amount of maximum allowable increases remaining available. 

### In other words, the increase or decrease in emissions was not included in determining the baseline concentration levels used in increment calculations
. 

### 6. Chapter 100.154
.H.: Regulated Pollutant Maine does not define the terms " Major New Source Review" or " Part 70 requirements" resulting in some ambiguity ofwhen greenhouse gases are considered a regulated pollutant.

" GHGs are a regulated pollutant, except that for the purposes of06-096 CMR 115 and 06-096 CMR 140, they are regulated pollutants only for the purposes of major New Source Review and Part 70 requirements. " Maine should clarify when greenhouse gases are considered a regulated air pollutant by either revising this language or defining the terms " major New Source Review" and " Part 70 requirements. 

### 7. Chapter 100.160. Significant Emissions: It is unclear whether the requirements in 160.A only apply between January 2, 3

### 2011 and July 1, 2011. To address this ambiguity Maine should add the phrase
" In addition to subparagraph A" at the beginning of subparagraph B. "ln addition to the provisions in subparagraph A, 

### beginning July 1, 2011, significant emissions for GHGs means any rate ofemissions that would equal or exceed 100,000 tons per year ofC02e at a new stationary source or an emissions
. .." Maine defines a major source as a source without a chapter 140 license. This definition causes an issue with the language in 160.A since most, ifnot all , existing part 70 sources will have a chapter 140 license. It appears the language contained 

### in the second halfof 160
.A. is intended to outline when greenhouse gas emissions must be addressed when an existing major source is making a modification. Given the definition of " Major source" in Chapter 100, the language in section 100.160.A. is inconsistent with 40 CFR 51.166. Maine should change its definition of" Major source" to be consistent with 40 CFR 51
. 166(b)(1 )(i), thereby ensuring modifications at existing sources properly address greenhouse gases. 

### 8. Chapter 100
. 161. Significant emission increase : This proposed definition removed paragraph D
. that stated " significant" means, 

### in reference to a net emission increase or potential ofa source to emit a regulated pollutant that paragraph 100.161.A. does not list, any emission rate. Federal and SIP-approved PSD programs apply a 0 tpy significance level for any regulated pollutant that does not have a defined regulatory mass-based significance level. To meet this requirement, the DEP should retain paragraph D. in its regulations
. 

### Chapter 115 : 

### Major and Minor Source Air Emission License Regulations 9
. 

### Chapter 115.2.U. 

### Pollution Control Projects: The courts have vacated federal regulations for pollution control projects. The DEP should remove this provision. 10. 

### Chapter 115.2
.R. 

### Replacement ofAir Pollution Control Equipment: This provision should clarify that air pollution control equipment shall be treated in the same manner as any other physical change or change in the method of operation
. to an emission unit. 

### 11. Chapter 115.4.B. 

### Process for a 

### Plantwide Applicability Limit (PAL) at a Major Sources: Chapter 115.4.8 ( 16) includes the requirements for the federal
"Equipment replacement provision" that the courts have now vacated. The DEP should remove this provision in 

### its entirety.



### 4

### Chapter 140: Part 70 Air Emission License Regulation 12. Chapter 140.1.C(S)(b) The delay in applying for an amendment to a title V license contained in this section is not allowed by 40 CFR part 70. An existing title V source which obtains a major new source review license must apply for a revision to its title V license pursuant to 40 CFR 70
.7(e)(4). This section requires the source to obtain a title V license amendment prior to operating the emission units subject to the major new source review license. Maine must remove the new requirement 

### in Chapter 140.1.C(8)(b). 

### 13. Chapter 140.1.D(3)(c) Regardless ofany restrictions on emissions a source may have 

### in a Chapter 115 license, any source that has received a major new source review license pursuant to Maine's SIP approved program must have a title V license. See Clean Air Act 

### § 502(a). 

### In addition, EPA has a policy that sources defined as major after the compliance date ofa MACT standard will not be allowed to restrict emissions to avoid title V applicability. Maine should remove this section from its rule or clarify the fact that emission restrictions in a Chapter 115 license do not always remove a source from Chapter 140
. 

### 14. Chapter 140.2.J(2)(c) There are two problems with this provision. First, changes requiring a major NSR license are not eligible for off license changes. These types ofchanges must be done using the significant modification procedures. Secondly, as stated 

### in comment 12, sources currently operating under a title V permit must apply for a license amendment prior to operating the affected emission unit(s). To be consistent with 40 CFR 70.4(b)(l4), please modify the eligibility for offlicense changes. 

### l 5. Chapter 

### l 40.2.K(3) Maine should add a requirement the public notice contain the DEP contact person for the licensing action. See 40 CFR 70.7(h)(2). 

### 16. Chapter 140.2.S Maine's proposed rule extends the permit terms and conditions when a complete renewal application as determined by the Department, is submitted at least 6 months prior to expiration but no earlier than 18 months. Part 70 allows a state program to either extend the permit terms and conditions or extend the permit.

5

### Forty CFR 70.4(b)(l0) states:

"A requirement under State law that, 

### if a timely and complete application for a permit renewal is submitted, consistent with §70.5(a)(2), but the State has failed to issue or deny the renewal permit before the end ofthe term ofthe previous permit, then: (i) The permit shall not expire until the renewal permit has been issued or denied and any permit shield that may be granted pursuant to §70
.6(f) may extend beyond the original permit term until renewal; or (ii) All 

### the terms and conditions ofthe permit including any permit shield that may be 

### granted pursuant to §70.6(f) shall remain in effect until the renewal permit has been issued or denied." Although subparagraphs (i) and (ii) allow a facility to continue to legally operate when a permit is extended, the ability to modify an extended permit is different between the two subparagraphs. 

### Ifa state wants to retain the ability to modify an**~xtended** 

### permit it must incorporate the language on subparagraph (i). This language extends the permit, thus allowing a permit to be 

### modified
. Subparagraph (ii) is limited to extending the permit' s term and conditions so there is no longer any permit to modify
. 17. Chapter 140, Appendix B, Section B 

### In the last few years EPA published requirements under 40 CFR part 63 for diesel generators and small boilers. Maine should consider removing these emission units , 

### listed as items B-2 and B-3 , from the list since they are subject to an applicable requirement. 18. Chapter 140.3.E(7)(b)(xiii)(d) 

### This section states : "The method(s), specified in the source ' s license, used for determining the compliance status ofthe source, currently and over the reporting period; and
.. ." Forty CFR 70
.6(c)(5)(iii)(B) is broader because it requires the source to determine compliance using other available information
. "The identification ofthe method(s) or other means used by the owner or operator for determining the compliance status with each term and condition during the certification period. Such methods and other means shall include, at a minimum, the methods and means required under 

### 6paragraph (a)(3) ofthis section
. . ." Maine should revise Chapter 140
.3
.E(7) (b) (xiii) (d) to also include information not specifically required by the license when determining the compliance status. 19. Chapter 140.7.A(S) : There appears to be a typo withln this section.

" Incorporates any other type ofchange which the Administrator has determined as part ofthe approved Part 70 program to be similar to those in paragraphs 40 CFR 60 § 70
.7(d)(l) (i) through (iv)." 20. The current introductory language to the list ofinsignificant activities based on emission or production rates does not specifically require the state to include these activities in a Chapter 140 license ifthe activity is sub j ect to an applicable requirement. We recommend Maine revise the current language as follows:

" The following units and activities are insignificant based on size or production and shall be listed on the Chapter 140 license application
. The activities will eut ma;· flOt be included in the Chapter 140 license ifthe activity is subject to an applicable requirement."

7 • 1 •