State of Maine 

Department of Environmental Protection 

Clean Air Act Section 182 (f) 

NO, Waiver Petition 

oE~N VIRON ,yFNt 

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ArE OF Mp~ 

BUREAU OF AIR QUALITY 

October 13, 2012 
Table of Contents 

I. EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 

II. BACKGROUND INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 

111. APPLICABLE EPA GUIDANCE FOR NO, CONTROL REQUIREMENT EXEMPTIONS . . . . . . . . . . . . . . . 3 

IV. SCOPE OF EXEMPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 

V. BASIS OF THIS PETITION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 

VI. TECHNICAL DOCUMENTATION . .. . . .. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 

A. OZONE BACK TRAJECTORY ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

B. NOZ DATA ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 

C. REGIONAL HAZE ANALYSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 8 

VII. SUMMARY OF RESULTS AND CONCLUSIONS FOR THIS PETITION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. . 13 

VIII. REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 

APPENDIX A - HYSPLIT TRAJECTORY DOCUMENTATION 

LIST OF FIGURES: 

Figure I - Northeastern U.S . Counties Ozone Designation with Class I Areas used in Regional Haze Analyses . . . . .. . ... . . . . . . . . . . 6 

Figure 2 - Back Trajectories from CT and Martha's Vineyard 2009-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 

Figure 3 - Portland, Maine Daily Maximum 1-hour Nitrogen Dioxide (N02) Concentrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 

Figure 4 - Nitrate Extinction 10 m Back Trajectories for Northeast Class I Areas When Nitrate Extinction is 

30 Mm" and above . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 

Figure 5 - Nitrate Extinction 10 m Back Trajectories for Northeast Class I Areas When Nitrate Extinction is 

between 15 through 29 Mm"' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .12 

LIST OF TABLES : 

Table 1 - 2008 NEI NO,, Emissions Inventory by State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 

Table 2 - Percent of Contribution to Light Extinction at Northeastern U.S . Class I Areas . . . . . . . . . . . . . . . . . . . . . . . . . 9 

Table A-1- Statistics on the Regional Haze Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2 
I. Executive Summary 

EPA previously granted the State of Maine, Clean Air Act (CAA) § 182(f) NO,, Waivers for nine 

counties under the 1-hour and 8-hour 1997 Ozone National Ambient Air Quality Standards 

(NAAQS). Since then a new 8-hr Ozone NAAQS was promulgated in 2008, a 1-hour NOZ 

NAAQS was promulgated in 2010 and Maine's Regional Haze SIP was approved in 2012. The 

entire State of Maine is in attainment for the 2008 8-hr Ozone NAAQS. Monitored NOZ data is 

well below the 1-hr N02 NAAQS. Regional Haze values in Maine are trending down and are 

below the SIP modeling glide path from the baseline to 2018. Per EPA guidance, photochemical 

grid modeling is not applicable in this case . Consequently, the analyses consist of: emissions 

inventory data for the Ozone Transport Region (OTR), back trajectories for ozone exceedance 

days, N02 data in Maine along with Regional Haze trends and trajectory analyses . 

The Maine Department of Environmental Protection's Bureau of Air Quality (MEDEP) is able to 

demonstrate that Maine does not contribute to nonattainment of ozone in the 8-hour Ozone 

NAAQS Nonattainment areas within the OTR. Thus, reductions of NOX emissions in Maine are 

not necessary to bring the ozone non-attainment areas in the OTR into attainment . Since 

Maine's monitored N02 values are well below the 1-hr N02 NAAQS, reductions of NOX 

emissions are not necessary for attainment . Furthermore, MEDEP is also able to demonstrate 

that Maine's NOX emissions do not significantly contribute to visibility degradation at any Class 

I Area in the Northeastern United States . 

MEDEP is therefore requesting a CAA §182(f) NOX Waiver under the 2008 8-hour Ozone 

NAAQS for the entire State of Maine. 

II. Background Information 

Oxides of nitrogen (NOX) emissions are precursors to ground level (tropospheric) ozone. When 

released into the atmosphere, NOX will react with volatile organic compounds (VOC) in the 

presence of sunlight to form ozone. Tropospheric ozone is an important contributor to the 

nation's urban and rural air pollution problem. 

In 2004, the US Environmental Protection Agency (EPA) designated and classified 8-hour 

Ozone NAAQS nonattainment areas in Maine based on the 1997 Ozone NAAQS of an 8-hour 

average of 0.08 parts per million. Those areas were Portland, ME - Subpart 2 Marginal 

Nonattainment (includes : Sagadahoc county and parts of Cumberland, York and Androscoggin 

counties) and Hancock, Knox, Lincoln and Waldo Counties - Subpart 1 Nonattainment (includes 

parts of each of the counties listed in the name). These 8-hour ozone nonattainment areas were 

later re-designated as attainment which was posted as a final rule in the Federal Register on 

December 11, 2006. 

In 2008, the new 8-hour Ozone NAAQS was promulgated at 0.075 parts per million which is 

equivalent to 75 parts per billion (ppb). Designations for the 2008 Ozone NAAQS were 

finalized on April 30, 2012. Design values for the entire State of Maine are currently below the 

2008 8-hr Ozone NAAQS and have been for two years. Consequently, all of Maine has been 

designated as unclassifiable/attainment for the 2008 Ozone NAAQS. 
Pursuant to the Clean Air Act Amendments of 1990 (CAAA), the entire State of Maine is part of 

the OTR. The OTR is a portion of the northeastern U.S. comprised of the six New England 

states ; New York, New Jersey, Pennsylvania, Maryland, Delaware, and the Consolidated 

Metropolitan Statistical Area that includes the District of Columbia and part of northern Virginia 

(see CAAA Section 184(a)). The purpose of creating this region was to require regional control 

strategies on ozone precursor emissions to address the problem of regional transport across state 

boundaries within the context of the State Implementation Planning process. All areas within the 

OTR became subject to a number of additional requirements . 

Existing major sources of NOX in the OTR are required to reduce NOX emissions through NOX 

Reasonably Available Control Technology (RACT). In addition, new major stationary sources 

and major modifications of NOX which are located in the OTR are subject to a 1 .15 emission 

offset requirement (see CAA Sections 182 (b) (5), 184 (b) (2), 182 (f) and MEDEP Regulations 

Chapter 113 (2) (C)). The NOX RACT requirement as well as the Lowest Achievable Emissions 

Rate (LAER) and 1 .15 NOX emission offset requirements hinder economic sustainability and 

development in Maine. 

The 1-hour N02 NAAQS was promulgated on January 22, 2010 with designations final on 

January 20, 2012 . EPA designated all areas of the country as unclassifiable/attainment. EPA 

stated that near-road monitors would be required to demonstrate compliance . Portland Maine's 

Deering Oaks monitoring site has not been declared an official near-road monitor; however 

MEDEP believes that this site currently provides the best representative data. 

Maine's Regional Haze SIP was approved on April 24, 2012. EPA has stated that the SIPs need 

to be done every ten years. A mid-coarse review at the five year mark is required to demonstrate 

whether or not the state is meeting the baseline to 2018 SIP modeled glide path. 

111. Applicable EPA Guidance for NOx Control Requirement Exemptions 

The CAA specifies in Section 182 (f) (1) that NOX requirements shall not apply if the 

Administrator determines that any one of the following tests is met: 

In any area, the net air quality benefits are greater in the absence of NO,, reductions 

from the sources concerned; 

In nonattainment areas not within an ozone transport region, additional NO, 

reductions would not contribute to ozone attainment in the area; or 

In nonattainment areas within an ozone transport region, additional NO, reductions 

would not produce net ozone air quality benefits in the transport region . 

In addition, Section 182 (f) (2) (A) states that the application of the NOX requirements may be 

limited to the extent that any portion of those reductions is demonstrated to result in "excess 

reductions" of NO,{. The NOx requirements of the conformity rules would also not apply in an 
area that is granted a Section 182 (f) exemption. Furthermore, certain NOX provisions of the 

inspection and maintenance (I/M) requirements would not apply in an area that is granted a 

Section 182 (f) exemption (not applicable to the areas currently seeking exemptions). The 

EPA's Guideline for Determining the Applicability of Nitrogen Oxides Requirements under 

Section 182 (f) describes how the EPA intends to interpret the NOX exemption provisions of 

Section 182 (f). 

IV. Scope of Exemptions 

If the EPA Administrator determines, under Section 182 (f) of the CAA, that additional 

reductions of NOX would not contribute to attainment of Ozone NAAQS, or are in excess to the 

reductions necessary for attainment, the area at issue shall automatically (i .e ., a State would not 

need to submit an exemption request for each requirement) be exempt from the following 

requirements (as applicable): the NOX related general and transportation conformity provisions, 

NOX RACT, offsets, LAER, and nonattainment area requirements under CAA Section 173 for 

existing sources, new sources and modifications that are major for NOx. Additionally, NOX 

emission reductions would not be required of an enhanced inspection/maintenance (I/M) 

program. 

V. Basis of this Petition 

The Maine DEP bases its petition on: a demonstration that NO., emissions in the State are not 

impacting nonattainment areas in the OTR during times when elevated ozone levels are 

monitored in those areas; and also on a demonstration that NO., emissions in the State are not 

significantly contributing to visibility degradation at any MANE-VU Class I Area. Current 

N02 data in the largest city in Maine is demonstrating continued compliance with the NAAQS. 

These conclusions are derived from the supporting analyses. As such, reductions in NO, 

emissions from Maine are not necessary for ozone attainment in these upwind areas and are 

excess to attainment under Section 182 (f) (2). Additionally, reductions in NO, emissions 

from Maine are not necessary for MANE-VU Class J 'Areas to remain at or below the baseline 

to 2018 SIP modeled glide paths. 

Consistent with EPA's Section 182 (f) guidance, the State's excess emissions reductions 

demonstration is tied to the attainment demonstration SIP required by the CAAA. The State of 

Maine will use a trajectory analysis to demonstrate that major source nonattainment requirements 

under CAA Section 173 for major source NOX RACT, major new sources and major 

modifications including LAER, and offsets requirements in the State are excess to the reductions 

necessary to attain the NAAQS for ozone in the nonattainment areas in the OTR. 

VI. Technical Documentation 

The purpose of this technical documentation is to support a demonstration that stationary source 

emissions from Maine do not contribute to ambient ozone in excess of the NAAQS, violations of 
N02 nor significantly to Regional Haze. Thus, reductions of NO, emissions in Maine are not 

necessary to bring the non-attainment areas in the OTR into attainment . 

In Chapter 7 of the Guidance on Limiting Nitrogen Oxides Requirements Related to 8-hour 

Ozone Implementation3, EPA states that "photochemical grid modeling is generally needed to 

document cases where NOX reductions . . . include excess reductions ." The next paragraph 

states : "It is important to note that EPA believes that photochemical grid models are not 

sufficient to assess incremental changes to area wide ozone concentrations from emissions 

reductions at a single or group of small sources. Emission changes should amount to some 

significant fraction of base emissions before modeling results can be interpreted with sufficient 

confidence that the results are not lost in the noise of the model and the input data. The EPA has 

reservations with respect to modeling NOX reductions at a single source or group of sources 

unless the modeling includes at least 10% of the domain-wide emissions." EPA retains the 

discretion to adopt approaches on a case-by-case basis that differ from the NOX Waiver guidance 

where appropriate. 

The total annual NOx emissions for the entire State of Maine are small, less than 3% of the OTR 

as displayed in Table 1 . Therefore, any reductions would be miniscule. So it is consistent with 

EPA's position, stated above, that photochemical grid modeling is not a viable analysis for 

Maine at this time. 

Table 1 : 2008 NEI NOX Emissions Inventory by State: 

OTR State Annual NOX Emissions (TPY) 

Connecticut 8593.24 

Delaware 13849 .35 

District of Columbia 579.88 

Maine 16761 .04 

Maryland 56790.36 

Massachusetts 23167.30 

New Hampshire 6969 .19 

New Jersey 28709 .12 

New York 78082 .37 

Pennsylvania 254591 .50 

Rhode Island 1630.71 

Vermont 501 .28 

Virginia 103626.50 

OTR Total 593851 .84 

Maine's Contribution 2.82% 

Several analyses center on whether or not Maine contributes to nonattainment or to visibility 

degradation. In order to provide a geographic understanding of the region, Figure 1 displays the 
2008 Ozone Nonattainment Designations with the Class I Areas in the Northeastern United 

States . 

Figure 1 : Northeastern U .S. Counties Ozone Designation 

with Class I Areas used in Regional Haze Analysis 

Created by Martha Webs[er MEDEP revised 5i14f12 based on EPA's 2008 Designations 

Legend 

* Class 1 Locations 

County Designation 

county 2012map 

' Unclassifiable/Attainment 

® Nonattainment 
A. OZONE BACK TRAJECTORY ANALYSIS 

MEDEP Air Quality Meteorologists conducted a trajectory analysis of ozone exceedance days 

for the 2009 through 2011 ozone seasons. A trajectory was created for each hour that ozone 

levels were equal to or greater than 75 ppb for every day that an 8-hour ozone exceedance was 

recorded. The analysis was conducted for monitoring sites in the nearest 2008 Ozone NAAQS 

Ozone Nonattainment Areas (which are the State of Connecticut and Martha's Vineyard in 

Massachusetts) . Figure 2 displays the hourly endpoints from back trajectories calculated for all 

days when sites in CT and Martha's Vineyard exceeded the 2008 Ozone NAAQS. It is clear that 

Maine does not contribute to ozone nonattainment within the OTR. Furthermore, transportation 

patterns haven't changed since Maine's last NOX Waiver was requested in 2005 . 

back irajectorivs at M., 160m and 250m AOL 

r ~.1ae,a'Neb~ar, Veins I3EP 11072011 
B. N02 DATA ANALYSIS 

EPA promulgated a 1-hour N02 NAAQS on February 9, 2010. EPA has stated that near-road 

monitoring is required to demonstrate compliance. Portland is Maine's largest city and includes 

many of the State's most heavily trafficked roads. The Deering Oaks Park monitor is located 

just off Interstate 295 near the intersection of Forest Avenue and State Street . This monitor 

began collecting data February 6, 2008. The chart below includes quality assured data through 

May 31, 2012. The daily maximum of hourly data from this site clearly demonstrates 

compliance with the 1-hour NOZ NAAQS as displayed in Figure 3. 

Figure 3: PORTLAND, MAINE DAILY MAXIMUM 1-HOUR NITROGEN DIOXIDE (N02) 

CONCENTRATIONS 

S 

a 

_o. 

c 

0 

r m 

w 

c m 0 

c 0 

v 

" 7-hr MAX Portland-DEERING OAKS - NAAQS 

C. REGIONAL HAZE ANALYSES 

NO, emissions not only contribute to the formation of ozone, but also to Regional Haze. 

Therefore, it is important to consider how Maine's NO, Waiver could impact Regional Haze in 

the Northeastern United States . Based on analyses conducted for MANEVU (Mid-Atlantic 

Northeast Visibility Union), Sulfate accounts for one half to two thirds of total fine particle mass 

on the 20 percent haziest days (20% worst) at all Class I areas in the northeast. Organic carbon 

typically consumes another 20 to 30 percent of total fine particle mass on the haziest days. 

Nitrates, elemental carbon (EC) and fine soil (FS) together are estimated to account for ten 

percent or less of the overall fine particulate mass. Nitrate is higher than EC and FS in urban 

areas most likely due to motor vehicle and other urban pollution sources. 
In addition to total fine particle mass, visibility parameters must be accounted for. The data" 

used in the analysis is the most recent quality assured data using the new revised Interagency 

Monitoring of Protected Visual Environments (IMPROVE) algorithm. The results presented 

here were part of a larger analysis created for MANEVU . The data was downloaded and 

compiled in Excel for the following Class I Areas in the MANEVU region : 

" Acadia National Park in Maine, 

" Moosehorn National Wildlife Refuge in Maine, 

" Great Gulf Wilderness Area in New Hampshire, 

" Lye Brook Wilderness Area in Vermont, and 

" Brigantine National Wildlife Refuge in New Jersey . 

Note: the first four Class I Areas listed above are in New England. 

Table 2 presents the relative contributions to light extinction for the 20% best (cleanest) and 20% 

worst (haziest) visibility days due to the following particles in the atmosphere : ammonium 

sulfate, ammonium nitrate, organic mass, light absorbing carbon, fine soil, coarse mass (PMIo), 

sea salt, and Rayleigh scattering. 

Table 2: Percentof Contributfonto Light Extinction at Northeastern i1.5 . Ctass I Areas 

0 

YI 

w 

Ammonium Light absorbing 

sutfate961ight Ammonium nitrate organic mass9L carbonBGiight Pinesoi19611ght coarsemass96 5eaSaft'%ItghtRayk:igh9blight 

site extinction 96fightextinction 1ightextinction extinction extinction tight extinction extinction extinction 

Baseline 2000-2004 Average 

Acadia NP 63.32 7 .66 10.19 4 .04 0 .48 1 .79 1.30 11 .22 

Mooseharn 60.02 6 .83 1218 4.53 0 .40 2.25 1.12 12.67 

GreatGulf 67.59 2 .75 12.76 3.54 0 .51 273 0.12 10.01 

LyeBrook 66.98 7.18 11.49 3.71 0 .49 1 .41 0.08 8.66 

Brigantine 66.07 8.17 12.32 3.61 0 .51 285 0.21 6.25 

2006-2010 Average 

Acadia NP 58.87 6.96 10.86 3.75 0.46 2 .80 1.72 1458 

Moasehorn 54.96 5.99 1291 4 .03 0S3 2.46 1.87 17 .27 

GreatGut( 6270 2.37 12.35 3 .70 0.52 3 .47 0.17 14 .73 

LyeBrook 6299 6.69 10.77 3 .89 0.62 256 0.30 1218 

Brigantine 59A4 10 .67 9 .94 4 .02 0.54 5 .79 0.98 8 .65 

BaseOne 2000-2004 Average 

Acadia NP 27 .90 4 .45 9 .25 3 .59 0.46 296 1 .82 49.58 

Moosehorn 26 .33 4 .19 1213 4.05 0.45 4.20 1 .19 47A6 

GreatGulf 26 .50 4 .44 9 .23 3 .83 0.47 4.02 0 .79 50.72 

LyeBrook 23 .17 6.01 6 .72 3.12 0.49 270 0 .27 57.53 

Brigantine 34.91 9 .09 10.72 5.70 0.55 7.55 3 .17 28.30 

2006-2010 Average 

Aadia NP 22.94 3 .17 8.55 289 OAO 3.72 2 .66 56.17 

Moosehorn 21.28 2 .82 9.15 3.06 0 .47 3.33 265 57.25 

GreatGufF 24.07 2 .82 7.82 3.15 0 .45 3.81 0.90 56.99 

LyeBrook 17.69 4 .22 4.20 2.28 OAO 269 0.58 67.94 

Brigantine 30.79 8 .45 9.79 4 .80 0 .64 8 .37 4.93 32.24 
The data for the 20% Worst Visibility Days for the Class I Areas closest to Maine is summarized 

as follows : 

Data for the years 2006-10 demonstrates that contribution to light extinction due to 

sulfates continues to dominate (55-63%) at all Northeast sites (note this is down from 60-

68% during the 2000-04 baseline period). 

Contribution to light extinction due to organic mass for the years 2006-10 is the third 

highest at all New England sites after light extinction due to Rayleigh scattering . For 

both the baseline and 2006-10 dataset it ranges from 10 to 13%. At Brigantine light 

extinction due to organic mass is greater than that due to Rayleigh scattering . 

Contribution to light extinction due to nitrate at all New England sites is less than 

Rayleigh scattering and is the fourth highest contributor to light extinction (note the 

average for 2006-10 is lower than the baseline years) . Brigantine's light extinction 

contribution due to nitrate is the second highest with Rayleigh scattering coming in fourth 

and has actually increased during the most current 5 year period. However, as 

demonstrated in the trajectory analysis to follow, Maine does not contribute to Brigantine 

on poor visibility days. 

Summaries on contribution to light extinction for the 20 % Best Visibility Days for the years 

2006-10 for the same Class I Areas are as follows: 

" Rayleigh scattering (56-68%) dominates (this is higher than the baseline years which 

ranged from (28-58%). , 

" Sulfate was second at 18-31% (note the range was 23-35% during the baseline years) . 

" Organic mass third at 4-10% (note the range was 7-12% during the baseline years) . 

" Nitrate is fourth at 3-8% (note the range was 4-9% during the baseline years) . 

This analysis demonstrates that, at all New England sites, nitrate is a very small contributor to 

light extinction for both the best and the worst visibility days. Values for the most current 5 year 

dataset are lower than during the baseline 5 year dataset. Yet, it is also important to document 

that if the NOX Waiver is granted Maine's emissions will not cause or contribute to backsliding at 

any Class I Area. 

Consequently, MEDEP Air Quality Meteorologists created back trajectories for a subset of the 

20% worst days for 2007 - 2010 from the same Class I Areas in the northeast. Appendix A 

includes information about how the data was processed to select dates for the Regional Haze 

trajectory analysis. In Figure 4, back trajectory endpoints for days with nitrate extinction values 

>30.0 Mm-1 were displayed. Figure 4 clearly demonstrates that Maine's NOX emissions do not 

cause or contribute to high levels of nitrate extinction at Class I Areas anywhere in the 

Northeastern United States . 
Figure 4 Nitrate Extinction 'ID m Back Trajectories for 

Northeast Class I Areas When Nitrate Extinction is 30 Mm4 and above 

Legend 

7k class i locations 

i tbl trajectory Events 

6ries ftom 20-doys at each site with the hghest nitrate 

®XUnE3iQn levels f[,-Vtha 20% worst v isib ikty da f s for 2007-2010 

Endpc.lnt !ites aaitsd i;~ N DRXs H YSPLI T dI31J2012 

To further demonstrate that Maine does not significantly contribute to visibility degradation, 

Figure 5 displays the back trajectory endpoints for days when the nitrate extinction values range 

from 15 .0 to 29.9 Mm-1 for all Northeast Class I Areas. In Figure 5 a few trajectories pass over 

11 
Maine so the height of the endpoints is also symbolized to help visualize what is happening on 

those days. Those trajectories that pass over Maine either : originate elsewhere and are 

descending from a higher altitude before reaching sites in Maine, or they begin in very rural 

areas of Maine with few emission sources then pass over large metropolitan areas to the 

southwest before reaching a Class I Area. 

Figure 5 Nitrate Extinction 10 m Back Trajectories for Northeast 

Class I Areas When Nitrate Extinction is 15 through 29 Mm" 

Legend 

* class1locations 

tbl trajectory Events 

height (m) 

<100 

100- 199 

200-399 

J 400-999 

" 7999 

rn 20days afsaCh sdewfth the highest nitrate 

e 20% worst viAi6iy'daps for 2001 -2010 

aaA~ HrsPUraraIrm12 
V1I. Summary of Results and Conclusions for this Petition : 

The entire State of Maine is attainment/unclassifiable for both the 2008 8-hour Ozone NAAQS 

and the 2010 1-hour N02 NAAQS. Regional haze in all MANE-VU Class I Areas is currently 

trending below SIP modeled glide paths. Technical analyses document that : 

NO,, emissions from Maine are much smaller than NO,, emissions emanating from 

sources in states to the south and west. This disparity in total stationary source NO, 

emissions is readily apparent from the information presented in Table 1 . 

Examination of Hybrid Single Particle Lagrangian Integrated Trajectory Model 

(HYSPLIT) back trajectories, for sites in the nearest nonattainment areas within the OTR, 

clearly illustrates that NOX emissions from Maine do not cause or contribute to ozone 

transport or production in any nonattainment areas within the OTR. Thus, reductions of 

NO,, emissions in Maine are not necessary to bring the non-attainment areas in the OTR 

into attainment . 

Monitored 1-hr N02 values in Maine's largest city, in an area of high traffic volumes, are 

well below the NAAQS. 

" Assessment of regional haze light extinction data shows that sulfates is the prime 

dominating contributor to regional haze in the northeast with nitrates contributing 

significantly less at levels below Rayleigh scattering . 

Assessment of regional haze, through HYSPLIT back trajectories during the 20% worst 

visibility days from Class I Areas in the Northeast United States, demonstrates that 

Maine's NOX emissions do not significantly contribute to visibility degradation. 

MEDEP is therefore requesting a NOX Waiver for the entire state. 
References 

Maine DEP-BAQ Regulations Chapter 113 : 

http ://www.maine .gov/sos/cec/rules/06/096/096c 113 .doc 

MANE-VU prepared by NESCAUM, Section 2.2 of Contributions to Regional Haze in the 

Northeast and Mid-Atlantic United States, finalized August 2006, printed October 2006 

U.S . EPA, 1990: Clean Air Act as Amended (CAAA) in 1990: http ://www.epa.gov/air/caa/ 

U.S. EPA, 1995 : Approval and Promulgation of Implementation Plans; Maine: NOX 

Exemption Request for Northern Maine and NOX Control Approval. Federal Register 60:247 

(26 December, 1995) p. 66748: http ://www.epa . ovg /fedrgrstr/EPAAIR/1995/December/Day-26/pr-368 .htm1 

U.S . EPA, 2005 : Guidance on Limiting Nitrogen Oxides Requirements Related to 8-Hour 

Ozone Implementation, Air Quality Strategies and Standards Division, Office of Air Quality 

Planning and Standards, January 14, 2005 : 

http ://www.epa. gov/ttn/oarpg/t 1 /memoranda/guide8hr-oz .pdf 

U.S . EPA, 2006a: Approval and Promulgation of Air Quality Implementation Plans; Maine; 

Nitrogen Oxides Exemption Request for Northern Maine. Federal Register 71 :23 (3 

February, 2006) p. 5791 : http ://www.epa.gov/fedrgstr/EPA-AIR/2006/February/Day03/a984 .htm 

U.S. EPA, 2006b: Approval and Promulgation of Implementation Plans and Designation of 

Areas for Air Quality Planning Purposes; Maine's Redesignation of the Portland, ME and the 

Hancock, Knox, Lincoln and Waldo Counties, Maine 8-hr Ozone Nonattainment Areas to 

Attainment for Ozone. Federal Register 71 :237 p. 71489, (11 December, 2006) : 

http ://www.epa. ov/fedrgstr/EPA-AIR/2006/December/Day-11/a20901 .htm 

Data for the Regional Haze analyses was gathered from the following web sites: IMPROVE 

data: http://vista.cira.colostate .edu/improve/Data/IMPROVE/summary data.htm and VIEWS 

data: http ://views.cira.colostate .edu/web/DataWizard/ 
Appendix A - Trajectory Analyses Documentation 

A trajectory is a three dimensional representation of the path an air parcel followed based on 

forecast or archived meteorological data. A back trajectory is the path the parcel took to reach a 

specific point in time and space . 

Maine Department of Environmental Protection's Bureau of Air Quality (MEDEP) 

Meteorologists conducted two trajectory analyses . 

O The first analysis was for the nearest 2008 Ozone NAAQS Ozone Nonattainment 

Areas at sites in Connecticut and Martha's Vineyard in Massachusetts. This analysis 

covered ozone exceedances for the 2009 through 2011 ozone seasons and included 

each hour that ozone levels were equal to or greater than 75 ppb at a monitoring site 

for every day that an 8-hour ozone exceedance was recorded. 24-hour back 

trajectories from 10, 150 and 250 meters (m) above ground level (AGL) were created. 

O The second analysis focused on regional haze and was based on visibility data for 

2007 - 2010 for the following Class I Areas in the northeast: Acadia National Park 

and Moosehorn National Wildlife Refuge in Maine, Great Gulf Wilderness Area in 

New Hampshire, Lye Brook Wilderness Area in Vermont and Brigantine National 

Wildlife Refuge in New Jersey . 48-hour back trajectories from 10, 150 and 250 

meters (m) above ground level (AGL) were created for each hour of the day. 

Information about how the days were selected for the analysis is placed after the 

Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) 

discussion . 

The National Oceanic and Atmospheric Administration (NOAA) Air Resources Laboratory's 

HYSPLIT is a computer model used to create and map trajectories . The model uses gridded 

meteorological data, which is selected within the online model's graphical user interface (GUI) . 

For more information about HYSPLIT please refer to the following document: Description of 

the HYSPLIT 4 Modeling System by Draxler and Hess 

(http://www.arl .noaa.gov/documents/reports/arl-224 .pdf). 

HYSPLIT is available for use online and also on a local computer (PC). MEDEP staff 

meteorologists used the online version to create the trajectories included in this analysis. To 

insure the hour of ozone matches with the hour of meteorology, the time of the ozone value was 

converted from Eastern Standard Time (EST) to Universal Time Code (UTC) by adding 5 hours. 

Archived ETA Data Assimilation System (EDAS) meteorological data at 40 km was used 

because this data set had the best resolution and had an excellent data recovery rate . The model 

was set to include vertical velocity. 

For each run, the HYSPLIT model generates both a graphical presentation of the trajectories and 

a text file . The text file contains information about the hourly endpoints along each trajectory 

path including the location in time and space. Hundreds of endpoint text files were subsequently 

loaded into an Access database for each analysis, which was then mapped in ARCMAP, a 

geographical mapping tool used within the department. 

A-1 

Maine's NOx Waiver Petition 2012 
DATA CALCULATIONS TO DETERMINE THE DAYS FOR THE REGIONAL HAZE 

TRAJECTORY ANALYSIS 

Regional Haze data was downloaded from the Visibility Information Exchange Web System (VIEWS) 

web site ( http://views .cira .colostate .edu/web/DataWizard ) . The data for each site included the visibility 

data in deciviews as well as the light extinction coefficient data in inverted mega meters (Mm-) for 

ammonium sulfate, ammonium nitrate, soil, elemental carbon, sea salt, organic carbon and coarse mass. 

Data was available on a 1 in 3 day monitoring cycle. 

This data was then sorted and processed to identify each year's 20% worst days based on the visibility 

parameter in deciviews . The 20% worst days were sorted by the ammonium nitrate light extinction 

coefficient . To ensure that a reasonable number of days were analyzed for each site, the highest 20 days 

of ammonium nitrate light extinction coefficient from the 20% worst days' visibility at each site were 

chosen for the trajectory analysis . This resulted in 100 site-days for which twenty-four hourly 48 hour 

back trajectories were calculated. 

Upon reviewing the nitrate light extinction data for the subset of days, 30.0 Mm"' was chosen because it 

seemed like a natural breakpoint to illustrate the differences between the New England sites and 

Brigantine in NJ. 15 Mm-1 was chosen as another breakpoint because it is half of 30. The title of each 

endpoint file contained a classification code, based on these breakpoints, to enable the display of 

trajectories in ARCMAP using the three nitrate light extinction classifications (i .e . above 30.0, 15.0 to 

29.9 and below 15.0 Mm"'). 

For the New England sites' subset of data, there was only one day (at Acadia) where the ammonium 

nitrate light extinction coefficient was slightly over 30 Mm'. The nitrate extinction values for the New 

England Class I Areas were usually below 15 Mm-1 . Conversely, Brigantine NJ's subset contained a high 

of 60 Mm-1 and only a few days below 30 Mm-1. Column 2 of Table A-1 shows the 2007 to 2010 count 

of available valid data days at each site from which to calculate each year's 20% worst days. Columns 3-

5 of Table A-1 characterize the nitrate light extinction values within the subset of 20 days from each site . 

Figure 4 in the NOx Waiver included 18 site-days (the total of column 3) and Figure 5 included 12 sitedays (the total of column 4). When all 100 site-days trajectories were mapped nothing substantial could 

be gleaned from the resulting image. Since nitrate light extinction is such a tiny fraction of total visibility 

degradation, the decision was made to display trajectories for only the higher values . 

Site Name Total # of Valid Days to # of days nitrate # of days nitrate # of days nitrate 

compute the annual 20% extinction >_30.0 extinction is >_15.0 extinction is < 

worst visibility days for Mm"' of the 20 and < 30.0 Mm-1 15.0 Mm-1 of the 

2007-2010 from the 20% of the 20 from the 20 from the 20% 

worst 20% worst worst 

Acadia 478 1 2 17 

Brigantine 411 17 3 0 

Great Gulf 371 0 0 20 

Lye Brook 413 0 6 14 

~ Moosehorn 469 0 1 19 

Table A-1 : Statistics on the Regional Haze Data Analysis 

A-2 

Maine's NOx Waiver Petition 2012