Responses to Significant Comments on the State and Tribal Designation 

Recommendations for the 2010 Sulfur Dioxide National Ambient Air Quality 

Standards (NAAQS)

Docket Number EPA-HQ-OAR-2012-0233

U.S. Environmental Protection Agency

July 2013
Page 2 of 63

Table of Contents

1.0 Introduction ..........................................................................................................4

2.0 Background ..........................................................................................................4

3.0 Responses to Significant Comments on the First Round of Initial Area 

Designations for the 2010 SO2 National Ambient Air Quality Standards (NAAQS).........5

3.1 General Issues...................................................................................................5

3.1.1. Not Yet Taking Action on Areas With No Monitored Violation .................5

3.1.2. Basing Nonattainment Designations on Modeling ......................................7

3.1.4. Requests to Extend the Public Comment Period .......................................10

3.2 Area-Specific Issues........................................................................................10

3.2.1. EPA Region 1 ..........................................................................................10

3.2.2. EPA Region 2 ..........................................................................................11

3.2.3. EPA Region 3 ..........................................................................................13

3.2.4. EPA Region 4 ..........................................................................................17

3.2.5. EPA Region 5 ..........................................................................................19

3.2.6. EPA Region 6 ..........................................................................................29

3.2.7. EPA Region 7 ..........................................................................................39

3.2.8. EPA Region 8 ..........................................................................................42

3.2.9. Multi-Region Areas..................................................................................59
Page 3 of 63

List of Abbreviations and Acronyms

CAA Clean Air Act

EPA Environmental Protection Agency

FR Federal Register

NAA Nonattainment Area

NAAQS National Ambient Air Quality Standard

NFR Notice of Final Rulemaking

OAQPS EPA Office of Air Quality Planning and Standards

PPB Parts Per Billion

SO2 Sulfur Dioxide

SIP State Implementation Plan

TPY Tons Per Year

TSD Technical Support Document 
Page 4 of 63

1.0 Introduction

This document, together with the preamble to the final designations action, and 

the Technical Support Documents (TSDs) for the designations, presents the responses of 

EPA to the significant comments we received on our initial designations decisions 

conveyed to states in February 2013. The responses presented in this document are 

intended to augment the responses to comments that appear in the preamble to the final 

action and the TSDs or to address comments not discussed in those documents.

2.0 Background

On June 2, 2010, the United States Environmental Protection Agency (EPA) 

revised the National Ambient Air Quality Standards (NAAQS) for sulfur dioxide (SO2) to 

provide increased protection of public health from SO2pollution. The EPA established a 

new primary 1-hour SO2 standard at a level of 75 ppb to protect against health effects 

associated with SO2 exposure, including a range of serious respiratory illnesses. The EPA 

retained the secondary 3-hour SO2 standard on March 20, 2012, to protect against welfare 

effects, including impacts on sensitive vegetation and forested ecosystems. 

History shows us that better health and cleaner air go hand-in-hand with economic 

growth. Working closely with the states and tribes, the EPA is implementing the 2010 

SO2 standard using a common sense approach that improves air quality and minimizes the 

burden on state and local governments. As part of this process, the EPA is working with 

the states and tribes to identify areas in the country that meet the standard and those that 

need to take steps to reduce SO2 pollution. Within one year after a new or revised air 

quality standard is established, the Clean Air Act (CAA) directs the Governor of each 

state to submit to the EPA a list of all areas in the state, with recommendations for 

whether each area meets the standard. As a first step in implementing the 2010 SO2

standard, the EPA asked states to submit their designation recommendations, including 

appropriate area boundaries, by June 3, 2011. The EPA later took steps to extend the 

designation process for the 2010 SO2 standard by 1 year due to having insufficient 

information to make initial area designations at that time. With this extension, the 

statutory deadline to complete designations is June 3, 2013.

On February 7, 2013, the EPA sent letters (often referred to as “120-day letters”) 

to state and tribal representatives responding to some of their recommendations and 

identifying an initial set of areas that do not meet the 2010 SO2 standard based on three 

years of monitoring data showing NAAQS violations. For other areas, EPA explained 

that it was not yet prepared to propose or take final designations actions. States, tribes, 

and the public had the opportunity to comment on the EPA’s preliminary designations 

decisions for the initial set of areas, and to provide new information and analyses to the 

EPA. 
Page 5 of 63

3.0 Responses to Significant Comments on the First Round of Initial Area 

Designations for the 2010 SO2 National Ambient Air Quality Standards (NAAQS)

The following sections are summaries of significant comments received on EPA’s 

preliminary designation decisions for the areas that EPA is designating nonattainment 

based on monitored violations, and the EPA’s responses to those comments. 

3.1 General Issues

3.1.1. Not Yet Taking Action on Areas With No Monitored Violation

Comment: EPA’s February 6, 2013, letters stated that EPA was not yet prepared to

include in the initial round of proposed designations any areas for the SO2 NAAQS which

had no monitors with 3 years of data showing violations. This approach does not appear 

to be an option for EPA to avoid issuing designations under the Clean Air Act. Therefore, 

EPA should designate all areas with no violating ambient monitoring data as 

"unclassifiable/attainment" since there is no evidence of violations in such areas. This 

approach is similar to the one taken by EPA when completing the initial designations for 

the 2010 short-term NAAQS for nitrogen dioxide (NO2). A designation is required under 

the CAA, and EPA should act to issue one of the three designations provided in the CAA. 

Failure to designate areas by June 2013 for the SO2 standard seems to be ignoring the 

statutory duty of EPA under the CAA and opening the door to litigation. This approach 

does not seem to be the best use of limited resources both at EPA and in the state 

agencies. Two other commenters also requested that EPA designate as unclassifiable 

those areas for which there is currently no SO2 air monitoring data, noting that this would 

enable EPA to meet its statutory deadline for completing designations. The commenters 

state that CAA section 107(d)(1)(A)(iii) provides that any area that cannot be classified 

on the basis of available information as meeting or not meeting the NAAQS should be 

designated as unclassifiable. The commenters note that EPA has designated areas as 

unclassifiable for several pollutants in the past, including an “unclassifiable/attainment” 

designation under the 2010 NO2 NAAQS for all areas in the country. The commenter 

further notes that for the 2010 NO2 NAAQS, EPA promulgated designations 

approximately two years after the new NO2 NAAQS was finalized and that since issuing 

those designations EPA has continued to work on collecting additional air quality data for 

the 2010 NO2 NAAQS.

EPA’s Response: These comments do not address, either in support or opposition, 

EPA’s specific proposed designations actions for the areas discussed in the agency’s 

February 6, 2013, letters regarding those specific areas. EPA is not yet taking any final 

action regarding other areas. Therefore, the comments are not germane to the specific 

proposed initial designations addressed in this final action, and are outside the scope of 

this action. It is therefore not necessary for EPA to respond to the points raised by these 

comments regarding other areas that are not addressed in this initial action, and EPA has 

neither proposed action for those areas nor taken final action for them in this round of

designations. 
Page 6 of 63

However, for informational purposes, EPA wishes to remind stakeholders that in the SO2

NAAQS final rule and past discussions with stakeholders, it has been frequently 

acknowledged that the current SO2 monitoring network provides relatively limited 

geographic coverage, and many monitors in the existing network are not sited with the 

objective of characterizing source-oriented maximum concentrations. The EPA is moving 

forward at this time with area designations for a set of areas with monitors showing 

violations based on 3 calendar years of data. As the EPA explained in the proposed 

designations, the agency is not at this time prepared to propose or take final designations 

action on other areas not addressed by our first round of proposed designations. In light 

of potential public health impacts that may exist but are not being adequately 

characterized by the existing monitoring network, the EPA believes that it would be 

preferable to obtain additional data and information regarding SO2 emissions at 

remaining areas to possibly support more definitive future nonattainment and/or 

attainment designations for such areas, rather than designating these areas as 

unclassifiable based on the limited information about SO2 air quality the agency now has.

The EPA developed a draft strategy for implementing the SO2 NAAQS on the basis of 

several stakeholder discussions that focuses on characterizing air quality in areas with the 

largest sources and then using these data for future designation actions. Under this draft 

strategy, if followed, states would have the flexibility to characterize air quality through 

monitoring or modeling, and, in addition to any case-by-case designations issued based 

on new information, two additional general rounds of designations would provide states 

time to collect this information. In developing this draft strategy, which continues to 

evolve, the EPA has taken into consideration the comments we received following the 

Final SO2 NAAQS Rule, the March 2011 draft designations guidance, the September 

2011 draft implementation guidance, and the three stakeholder meetings held in 2012. 

After assessing the different issues raised in these comments, the EPA hopes to follow 

what it believes is the most common-sense approach for implementing the SO2 NAAQS. 

The agency expects that this approach will allow each state to take a primary role in 

deciding how to characterize air quality in its own priority source areas.

Comment: The commenters state that EPA has not identified a statutory basis to delay 

designations pending planned revisions to the SO2 monitoring network requirements as 

part of the implementation of the 2010 1-hour SO2 NAAQS. The commenters believe that 

in similar fashion to the 2008 lead NAAQS, EPA should not allow future planned 

revisions to the existing SO2 monitoring network requirements to result in the delay of 

designations for any areas in the country. 

EPA’s Response: As stated in the February 15, 2013 Federal Register notice of 

availability and public comment period for EPA’s responses to state and tribal SO2

designation recommendations (78 FR 11124), the EPA is not yet prepared to respond to 

state and tribal area designation recommendations, or seek public input thereon, for areas 

other than those with monitored violations of the 2010 SO2 NAAQS addressed in the 

February 15, 2013 notice. EPA intends to address the remaining areas in the country, 

including those areas for which there is currently no SO2 air monitoring data, in a 

subsequent round or multiple rounds of responses and designations once additional data 

are gathered. However, as is made clear in the February 15, 2013 notice, the EPA in that 
Page 7 of 63

action was not proposing as a regulatory action and was not soliciting public comments 

on the intended approach for these other areas, regarding either designations or 

implementation. Opportunities for additional public input on EPA’s intended approach 

for these other areas will be available. We invite future public participation from this 

commenter and others when these opportunities are provided.

Comment: Multiple commenters discuss that the ambient monitoring data demonstrates 

compliance with the 1-hour SO2 NAAQS and that EPA has approved their monitoring 

networks and even previous State Implementation Plans (SIPs). This information should 

not be disregarded. Additionally, EPA has acknowledged in the 120-day letters that 

2009-2011 air quality data shows no violations of the 2010 SO2 standard in many of 

Region 8’s counties. Thus EPA should proceed with designations for all areas based on 

the information that is presently available and not defer. Further, the deferral ignores 

Section 107 of the Clean Air Act’s timeline for designations and nowhere in the CAA 

does it allow EPA to defer designations any further then past the 1-year extension that 

EPA has already taken. EPA recognized and anticipated at the time of the 1-year 

extension that most areas of the country will be designated unclassifiable. One 

commenter discusses that EPA seems to be contemplating future rulemaking to require 

some level of modeling analysis to accompany the analysis on monitored data but since 

this rulemaking does not exist at this time designations should be completed. Another 

commenter discusses the negative effects of deferral which include development of a new 

SIP without having effective designations in place, harm to stakeholders by not providing 

clear designations, uncertainty for another eight years, state planners do not know where 

to direct resources due to EPA’s indecisiveness, and the deferred planning schedule will 

overlap the 2015 designation process.

EPA’s Response: EPA disagrees with the commenters assertion that EPA is disregarding 

monitoring data and previous SIPs in this initial round of final designations, since we are 

not at this time reaching any final conclusions about areas that do not have violating 

monitors. Objections to EPA’s not yet addressing other areas are outside the scope of 

this final action, and all concerns regarding the treatment of such areas should be raised 

in response to EPA’s future proposed designations for those areas. 

Comment: One commenter says EPA should follow what was done for the 1-hour NO2

designation process, which met the requirements of the CAA but also allowed for more 

time to collect data.

EPA’s Response: At this time, we are only initially designating areas with violating 

monitors, and are not yet prepared to address the remaining areas. Concerns about how 

such remaining areas are addressed should be raised in response to our future proposed 

designations for those areas. 

3.1.2. Basing Nonattainment Designations on Modeling

Comment: A couple of commenters said that EPA’s intention in its February 2013 120-

day letters to designate 30 areas consisting of just 10 counties and 31 partial counties, 
Page 8 of 63

while not proposing or issuing final designations for the remaining roughly 3000 counties 

in the country for years beyond the June 2013 designation deadline is unlawful. The 

existing SO2 monitoring network is inadequate to the task of ascertaining attainment; nor 

is reliance on monitors alone effective for determining what areas are failing to attain the 

NAAQS. Instead, EPA must base its designations on all evidence before it, including 

modeling analyses, as has been its longstanding historical practice.

EPA must designate all areas as nonattainment for which modeling shows exceedances of 

the NAAQS. Even under EPA’s delayed implementation schedule, designations must be 

made based on modeling.

For the foregoing reasons, EPA must designate in June 2013 as nonattainment all those 

areas modeled to have exceedances of the 1-hour SO2 NAAQS in the enclosed analyses. 

Absent such nonattainment findings, the SIPs prepared and submitted by the states will 

be inadequate unless they include or reference federally enforceable emission limitations 

informed by modeling sufficient to prevent exceedances of the standard.

EPA’s Response: The majority of these comments, including modeling analyses, do not 

address, either in support or opposition, the EPA’s specific intended designations actions 

for the areas discussed in the agency’s February 6, 2013, letters regarding those specific 

areas. Therefore, these points are not germane to the specific proposed initial 

designations, and are outside the scope of this action. It is therefore not necessary for the 

EPA to respond to the points raised by these comments regarding other areas that are not 

addressed in this initial action, and the EPA has neither proposed a designation action for 

those areas nor taken final action for them in this round of designations. Nor has the EPA 

proposed action or taken final action regarding whether other evidence such as modeling 

may support specific nonattainment designations under the 1-hour SO2 NAAQS. The 

EPA will take the commenters’ points under advisement when other areas are addressed, 

and urge commenters to re-submit their comments in response to the EPA’s future 

proposed designations, when they occur, if the commenters still have such concerns at 

that time.

Nine of the SO2 emissions sources identified in these comments are located within the 

boundaries of the nonattainment areas the EPA is finalizing at this time. The modeling 

and other information provided by the commenters does not appear to conflict with 

EPA’s conclusions regarding the areas currently being designated nonattainment, which 

EPA is basing at this time on the available monitoring data. EPA is not at this time 

prepared to reach final conclusions based on such modeling information, either to reject 

or accept it as a basis for expanding our first round of nonattainment designations. 

EPA is moving forward at this time with area designations for a set of areas with 3 years 

of monitoring data showing violations. The Federal Register notice announcing the public 

comment period for the proposed designations was specific to those areas we are 

currently designating nonattainment and the commenters did not submit any information 

suggesting they object to the proposed nonattainment designations for those specific 

areas. EPA has developed a draft strategy for implementing the SO2 NAAQS on the 

basis of meetings with several stakeholders that focuses on characterizing air quality in 

areas with the largest sources and in the more populated areas and using this data in 
Page 9 of 63

future designations. Under this draft strategy, if followed, states would have the 

flexibility to characterize air quality in these areas through monitoring or modeling, and 

additional rounds of designations (in addition to any case-by-case designations based on 

new information) would provide states time to collect this information and provide it to 

EPA as it becomes available. In developing this draft strategy, which continues to evolve, 

EPA has taken into consideration the comments we received following the Final SO2

NAAQS Rule, the March 2011 draft designations guidance, the September 2011 draft 

implementation guidance, and the three stakeholder meetings held in 2012. After 

assessing the different issues raised in these comments, the EPA hopes to follow what it 

believes is the most common-sense approach for implementing the SO2 NAAQS. 

As stated above, the EPA did not propose and is not taking final action at this time to 

conclude whether modeling and other information besides monitoring is appropriate to 

support specific designations under the SO2 NAAQS. Instead, we are only concluding 

that the initial designations of nonattainment are appropriate for the specific areas where 

3 calendar years of monitoring data support a conclusion that the NAAQS is violated. 

The EPA intends to further address how modeling may be appropriately used in future 

designations for additional areas under the SO2 NAAQS in forthcoming rulemaking and 

technical assistance documents.

3.1.3. Revocation of Old Standard

Comment: EPA should forward with revocation of the older SO2 standards (annual and 

24-hour standards).

EPA’s Response: The final SO2 NAAQS rulemaking already addressed how and when 

revocation of the prior primary NAAQS would occur, and EPA did not propose to reopen 

that issue in this action. Therefore, it is outside the scope of this final designations 

action, and it is not necessary for EPA to respond to this comment. However, for 

informational purposes, EPA directs the commenter to the final NAAQS preamble’s 

discussion of this issue, at 75 FR 35549-50, 35580-82, and to the regulatory text adopted 

with the NAAQS at 40 CFR 50.4(e). This regulatory text provides that the prior primary 

SO2 NAAQS will remain applicable to an area until 1 year after the effective date of that 

area’s designation under the 1-hour SO2 NAAQS, and then no longer apply, except in the 

case of areas that at the time of promulgation of the 1-hour NAAQS were designated 

nonattainment under the prior primary NAAQS or were not meeting the requirements of 

a SIP call under the prior NAAQS; for those areas, the prior NAAQS would not be 

revoked until the area submits under CAA section 191 and EPA approves a SIP providing 

for attainment of the new 1-hour NAAQS. 40 CFR 50.4(e). In the preamble discussion 

of this issue, EPA explained that states were directed to continue implementing 

attainment and maintenance SIPs associated with the prior NAAQS until they are 

subsumed by any new planning and control requirements associated with the new 

NAAQS, in order to assure compliance with the Clean Air Act requirements of section 

110(l), 172(e) and 193, as applicable. 75 FR at 35580-82. We note that in none of the 

several petitions for administrative reconsideration of the final NAAQS that we received 

did anyone ask us to revisit this issue. Nor did any of the numerous litigants challenging 
Page 10 of 63

the final NAAQS object to our treatment of revocation of the prior NAAQS. We do not 

regard the comments on the proposed designation action as constituting a new 

administrative petition for rulemaking to revise the final NAAQS rulemaking’s 

promulgation of 40 CFR 50.4(e), as in our proposed designation action we gave no 

indication of any intention to reopen that issue. Finally, if we were to amend section 

50.4(e), the rulemaking requirements of CAA section 307(d) would apply to such an 

action, while under CAA section 107 no such requirements apply to designations actions 

and we did not voluntarily designate this action as a section 307(d) rulemaking. 

Therefore, this action would not have been an appropriate one for undertaking any 

amendment to 40 CFR 50.4(e).

3.1.4. Requests to Extend the Public Comment Period

Comment: Several commenters from industries stated that the 30-day comment period is 

too short to effectively review the EPA’s response to state’s recommendations and 

compile meaningful responses; therefore, they requested a 30-day extension to the public 

comment period. This will allow them time to more thoughtfully consider both the 

policy and technical issues associated with the proposal. Specifically, the SO2 issue in the 

Billings/Laurel, MT area is very complex and EPA’s upcoming designation will have a 

significant impact on the area. There exists much historical and contemporaneous 

information that makes this area unique. Some of this information has already been 

submitted to EPA, but there is additional information and related comments that EPA 

should consider and more time is needed to compile, review and submit this information. 

Commenters believe the additional time is reasonable and fair given the potential and 

severe long-term effects of the proposed determination on Montana, the county, its 

diverse stakeholders and in the proposed rejection of Montana's own 2011 proposal. 

Given EPA has had nearly 2 years to consider Montana's (and others) comments, it seems 

reasonable to allow the public an additional 30 days for review.

EPA’s Response: The EPA appreciates the time and effort of the commenters in 

participating in this matter. The EPA invited public comments on its responses to States 

and Tribes through March 18, 2013, and states were asked to comment by April 8, 2013.

The EPA was able to accommodate the requests for an extension of the public comment 

period through April 8, 2013. Due to the statutory timeframe for promulgating 

designations set out in CAA Section 107(d), the EPA was unable to consider any public 

comments past April 8th. The April 8th deadline was necessary to allow EPA sufficient 

time to review and respond to all significant comments in advance of promulgating the 

2010 SO2 designations in July 2013.

3.2 Area-Specific Issues

3.2.1. EPA Region 1

3.2.1.1. State of Connecticut
Page 11 of 63

Comment: EPA should designate Connecticut as attainment for the SO2 NAAQS. In 

addition to monitoring SO2 levels well below the NAAQS, DEEP has completed 

modeling of all sources in Connecticut with greater than 100 tpy actual emissions. This 

modeling, when based on actual emissions for those emission units with CEM data and 

allowable emissions for those units without CEM, shows attainment of the NAAQS.

EPA’s Response: In this designations action, EPA is limiting its final conclusions to 

those areas with 3 calendar years of data showing violations of the 1-hour SO2 NAAQS. 

Therefore, this comment is outside the scope of this specific final designations action. In 

EPA’s February 2013 proposed response to certain state and tribal designation 

recommendations for the SO2 NAAQS, EPA solicited comments regarding a specific set

of areas which the Agency proposed to designate nonattainment. We specifically stated 

we were not soliciting comments on or prepared to propose designations for other areas 

for which states and tribes have submitted designation recommendations, including any 

areas that may ultimately become designated unclassifiable or attainment or for which 

modeling might be used to support a final designations decision. The EPA is still not yet 

prepared to respond to state and tribal area designation recommendations for these other 

areas, and intends to address such areas in a subsequent round or multiple rounds of 

proposed responses and final designations actions. At this time, EPA is not reaching a 

final decision in response to whether Connecticut has shown attainment of the 1-hour 

SO2 NAAQS.

3.2.1.2. Central New Hampshire 

Comment: One commenter agrees with EPA’s proposal to designate a portion of New 

Hampshire as nonattainment for the SO2 NAAQS. The commenter states that, “New 

Hampshire’s recommendation correctly reflects the requirements of the Clean Air Act 

and its implementing regulations, which compel EPA to designate as SO2 nonattainment 

areas the highlighted parts of Hillsborough, Merrimack, and Rockingham Counties. In 

addition, the proposed nonattainment designation is not only consistent with the law, but 

it is also necessary to protect public health and the environment.” The highlighted area 

referred to in CLF’s letter is the same area known as the Central New Hampshire SO2

nonattainment area in EPA’s Technical Support Document. 

EPA’s Response: The EPA acknowledges the commenter’s support.

3.2.2. EPA Region 2

3.2.2.1. Warren County, NJ

Comment: One commenter recommends a nonattainment designation for Warren County 

and its surrounding area due to the impacts from the nearby Portland Power Plant. The 

commenter requests EPA reconsider its decision to not move forward with a 

nonattainment designation of Warren County and its vicinity.
Page 12 of 63

The commenter states that EPA is without authority under the Clean Air Act to delay this 

nonattainment designation, which is in accordance with the evidence. Data from the 

Columbia Lake Wildlife Management Area (Columbia Lake) monitor, as well as 

modeling performed by NJDEP and EPA, demonstrates that the NRG/GenOn Portland 

Power Plant significantly contributes to and causes nonattainment of the 1-hour SO2

NAAQS in New Jersey. The monitor continues to measure exceedances of the health 

standard when the coal units operate and the wind blows from the Portland stacks toward 

the monitor.

EPA’s Response: After considering the recommendation and the additional information 

provided by New Jersey, we are still not prepared at this time to include the Warren 

County, New Jersey area in this initial round of final designations that is based only on 

monitors with 3 calendar years of data showing violations of the 1-hour SO2 NAAQS.

Moreover, as explained earlier, EPA is still not prepared at this time to base proposed or 

final nonattainment designations under the 1-hour NAAQS on modeling data, whether 

alone or as a supplement to complete or incomplete monitoring data. For this first round 

of SO2 designations, only areas with monitored violations of the standard shown by 3 

calendar years of data are being considered, as we explained in the proposal, and the 

Columbia Lake monitor had not at proposal and has still not been in operation at its site 

for 3 calendar years, and has not yet generated the necessary amount of data. Under 

EPA’s rules, in order to calculate a valid design value for the area on which to base a 

designation based on monitoring, three complete calendar years of data are required.

There are currently less than three complete calendar years of data for the air monitor 

located in Warren County, which began operating in September 2010. We recognize that 

additional data will be available soon, and we will continue to work with New Jersey and 

proceed as appropriate as additional monitoring data become available for the Warren 

County area, and as we further address how to consider modeling information to support 

designations under this NAAQS.

Comment: One commenter mentioned that federal regulations allow for data substitution 

in accordance with 40 CFR Parts 50-Appendix T, “Interpretation of the Primary National 

Ambient Air Quality Standards for Oxides of Sulfur (sulfur dioxide)-Section 3(d). In 

fact, the USEPA is currently applying this rule to other sites with less than 75% data 

capture in a year, notably the monitor in Muscatine, Iowa, where missing data was 

substituted with zero values to declare the county as not attaining the health standard.

EPA’s Response: Since the monitor in Warren County, New Jersey has not been in 

operation and generating data for the necessary 3 calendar year period in order to support 

a final nonattainment designation based on monitoring, we consider the request to 

designate Warren County based on a shorter period of monitoring operation as outside 

the scope of this final designations action. We disagree with the suggestion that the data 

substitution authority of 40 CFR part 50, appendix T, section 3(d) could be appropriately 

used in a situation where a monitor has not actually been in place for 3 years and there is 

no period in which the monitor “failed” to generate the data is was expected to provide. 

The data substitution authority presumes that an actually sited monitor had been expected 

to be operating and generating data over the subject 3 year period, but had for some 
Page 13 of 63

reason failed to generate valid data for some period within its 3-year operating period. 

The 2010 final SO2 NAAQS preamble discussion regarding the appendix T data

substitution nowhere suggests that the data substitution authority should be used to create 

a fictional period of monitor operation and data where a monitor did not actually exist for 

the assumed 3-year period. See 75 FR at 35582-85, and 40 CFR part 50, appendix T, 

section 3. Such a situation is very different from the Muscatine, Iowa situation, in which 

a monitor has been in place and operation for well over the minimum 3-year period, but 

failed to generate the expected amount of valid data and there is a missing period for 

which to substitute data. In Warren County, there is no period in which the monitor 

failed to generate data it was expected to provide, so there is no “gap” for which to 

substitute data. Finally, we note that in Warren County the minimum necessary 3-year 

period of the monitor’s operation will soon pass, and after that the EPA will be able to 

work with New Jersey to proceed as appropriate in response to the data the monitor has 

produced at that time. Therefore, we are not now prepared in this final designations 

action to extend the data substitution authority to a situation where there is no failed 

monitored period for which to substitute data that, under our rules, does not appear to 

have been contemplated. 

3.2.3. EPA Region 3

3.2.3.1. State of Delaware

Comment: On June 13, 2011 Governor Jack Markell recommended that the EPA 

designate each of Delaware’s three counties as unclassifiable for the 2010 75 ppb 1-hour 

SO2 NAAQS. Delaware now has a complete SO2 monitoring network, and has complete 

air dispersion modeling that clearly supports a designation of attainment for the entire 

state. 

EPA’s Response: The comment is outside the scope of this final designations action 

based on monitoring data. In this final action, EPA is only issuing final nonattainment 

area designations for areas with monitors that have 3 calendar years of data showing 

violations of the SO2 NAAQS. EPA is not prepared that this time to address or take any 

action on other areas, which we will address in future final designations actions. Once 

EPA starts to address these other areas, the state may wish to provide this information for 

the record at that time. 

3.2.3.2. Allegheny, PA Area

Comment: NRG Energy agrees with USEPA’s proposed nonattainment area for 

Allegheny County. The commenter indicates it is appropriate that the Elrama Generating 

Station located in Washington County PA should not be included in the nonattainment 

area. SO2 ambient air monitoring exceedances and SO2 emissions from Elrama were 

reviewed by the commenter and the commenter surmises that the analysis suggests that 

exceedances in Allegheny County may occur independent of operations at Elrama. 

Additionally the commenter indicates that the emission units at Elrama are currently in a 

layup status.
Page 14 of 63

EPA’s Response: The EPA concurs in general with the commenter’s main point that 

EPA is not yet prepared to include the Elrama facility in Washington County, PA in the 

Allegheny PA nonattainment area. EPA does not feel there is sufficient information at 

this time to determine the designations status of any portion of Washington County PA, 

or support including any portion of Washington County PA in the initial Allegheny 

nonattainment area. At this time EPA is designating as nonattainment a portion of 

Allegheny County. Additional technical information on these topics can be found in the 

Allegheny PA Nonattainment Area section in the TSD that accompanies this action. 

However, EPA is also not yet prepared to reach any final decisions regarding whether the 

Elrama facility contributes to NAAQS violations on any other basis, and we will further 

address this source and Washington County in a future final designations action.

Comment: One commenter requests that EPA include portions of Washington County in 

the nonattainment area designation for the following reasons:

1. Two significant sources of SO2 that combine to emit over 3,500 tons of SO2 (based 

upon USEPA data) are located in close proximity of the Liberty monitor; and their 

location is south/southwest of the Liberty monitor, which EPA acknowledges are in a 

geographic location most likely to impact the Liberty monitor.

2. One source in Washington County is a local source (just over the border between 

Allegheny and Washington) that directly contributes to air quality conditions during 

inversion events which EPA alleges are the reasons for the exceedance at the Liberty 

monitor.

3. EPA has acknowledged the appropriateness to include significant sources of SO2

beyond county lines in nonattainment designations, as it has with the Indiana 

nonattainment area, which includes Armstrong County.

For these reasons, the commenter encourages EPA and PADEP to include portions of 

Washington County with large SO2 sources that are located in a geographic area most 

likely to impact the Liberty monitor as part of the nonattainment area.

EPA’s Response: The EPA is not yet prepared, based on current information related to 

the monitored violation in Allegheny County, to conclude that sources in Washington 

County PA contribute to those monitored violations. The EPA will further address the 

Washington County sources in a future final designations action. While the EPA 

acknowledges that in some cases it is appropriate to include nearby sources beyond 

county lines in this initial round of monitoring-based designations, inclusion of additional 

sources is on a case by case basis, and in many cases we are choosing to limit the scope 

of our initial nonattainment designations while reserving for future analysis in a 

subsequent round of designations whether nearby sources and areas are causing or 

contributing to violations. In such cases, as in this one, we are not yet reaching final 

conclusions regarding initially excluded sources and areas. Regarding items #1 and #2, 

for now EPA acknowledges that there are sources in Washington County located near 

Allegheny County, but notes that emissions from these sources have been decreasing and 
Page 15 of 63

that one source is not currently operating. Despite an overall decrease in emissions from 

the sources in Washington County, the SO2 levels at the Liberty monitor in Allegheny 

County has shown little variation, suggesting it is being primarily impacted by other 

sources. Additional information and technical analyses for both the Indiana PA 

Nonattainment Area and the Allegheny PA Nonattainment Area can be found in the 

Pennsylvania TSD which accompanies this action.

Comment: One commenter applied EPA’s five factors for determining attainment with 

the new 1-hour SO2 NAAQS and has determined that most of Allegheny County should 

not be designated as nonattainment. Rather, the commenter proposes the partial county 

“Lower Monongahela Valley SO2 Nonattainment Area,” which would include the 

following municipalities in Allegheny County: West Mifflin, Dravosburg, McKeesport, 

Versailles, Port Vue, Glassport, Liberty, Lincoln, Clairton, West Elizabeth, Elizabeth 

Township, Borough of Elizabeth, Forward, Jefferson Hills, and Pleasant Hills. Union 

Township and Finleyville Borough in Washington County should also be included in this 

nonattainment area as a partial county combination of the Monongahela Valley and 

Allegheny County Air Basins within the Southwest Pennsylvania Intrastate AQCR. The 

commenter asserts that the remainder of the county should be excluded from the 

nonattainment designation based on the application of EPA’s five factors.

Based on the results of the commenter’s analysis using EPA’s five factors for 

determining attainment with the new 1-hour SO2 NAAQS, the commenter recommends 

that only the municipalities in Allegheny County and Washington County that were 

identified above be designated as the “Lower Monongahela Valley SO2 Nonattainment 

Area.”In addition, the commenter recommends that portions of Washington County

should also be included in the Allegheny County nonattainment areas. 

EPA’s Response: EPA agrees that only a portion of Allegheny County needs to be part 

of the initial nonattainment area, while reserving for further analysis in a future 

designations action how other nearby areas should be designated. However in addition to 

the areas identified by ACHD, EPA is designating a few other portions of the county as 

part of the nonattainment area since a source of significant SO2 emissions is located 

within these additional portions of the county.. EPA does not agree that there is yet 

sufficient information to determine that a portion of Washington County PA should also 

be included in the Allegheny PA Nonattainment Area. Sources in Washington County 

will be further addressed in a future final designations action. Additional information can 

be found on these issues in the PA TSD in the section discussing the Allegheny PA 

Nonattainment Area.

Comment: Reduce the Allegheny County nonattainment area to the municipalities of the 

City of Clairton, the City of McKeesport, Dravosburg, Elizabeth, Glassport, Jefferson 

Hills, Liberty, Lincoln, Pleasant Hills, Port Vue, Versailles, West Elizabeth and West 

Mifflin Boroughs, and Elizabeth and Forward Townships. The reason for the 

recommended modification of the Allegheny County nonattainment area is outlined in 

Pennsylvania’s revised recommendation letter, which can be found in the federal docket 

system.
Page 16 of 63

EPA’s Response: EPA agrees that only a portion of Allegheny County needs to be part 

of the initial nonattainment area, while reserving for further analysis in a future 

designations action how other nearby areas should be designated. However in addition to 

the areas identified by the Commonwealth, EPA is designating some other portions of the 

county as part of the nonattainment area since a source of significant SO2 emissions is 

located within these additional portions of the county . Additional information can be 

found in the TSD in the discussion of the Allegheny PA Nonattainment Area.

3.2.3.3. Beaver, PA Area

Comment: Reduce the Beaver County nonattainment area to six municipalities: 

Brighton, Potter and Vanport Townships and Industry, Midland, and Shippingport 

Boroughs. The reason for the recommended modification of the Beaver County 

nonattainment area is outlined in Pennsylvania’s revised recommendation letter, which 

can be found in the federal docket system.

EPA’s Response: EPA reviewed the information provided by the Commonwealth and 

concurs that the initial Beaver PA Nonattainment Area should be reduced from the 

original proposal of the entire county to a partial county consisting of the municipalities 

identified by the Commonwealth of Pennsylvania. EPA will designate currently 

excluded areas in a future round of final designations. Additional information and 

analysis regarding this area is contained in the PA TSD that accompanies this action in 

the section of the TSD that discusses the Beaver PA Nonattainment Area. 

3.2.3.4. Indiana, PA Area

Comment: EPA responded to the Commonwealth's designation recommendations, 

agreeing with all of Pennsylvania's original designation recommendations, but also 

including a portion of Armstrong County as part of a nonattainment area. After 

consideration of EPA's intention to add a portion of Armstrong County, and after further 

analysis, the state recommends that EPA remove the intended partial designation of 

Armstrong County for the reasons outlined in Pennsylvania’s revised recommendation 

letter, which can be found in the federal docket system.

EPA’s Response: EPA agrees with the Commonwealth regarding the inclusion of all of 

Indiana County in the nonattainment area. However, EPA does not concur with 

removing the portions of Armstrong County that were in the proposed nonattainment 

area. EPA reviewed the additional information provided by the Commonwealth but did 

not find it sufficient to justify removing the portions of Armstrong county from the 

nonattainment area. Additional information and analysis regarding this area is contained 

in the PA TSD that accompanies this action in the section of the TSD that discusses the 

Indiana PA Nonattainment Area.

3.2.3.5. Warren, PA Area
Page 17 of 63

Comment: Reduce the Warren County nonattainment area to four municipalities: 

Conewago, Glade and Pleasant Townships and the City of Warren. The reason for the 

recommended modification of the Warren County nonattainment area is outlined in 

Pennsylvania’s revised recommendation letter, which can be found in the federal docket 

system.

EPA’s Response: EPA reviewed the information provided by the Commonwealth and 

concurs that the initial Warren PA Nonattainment Area should be reduced from the 

original proposal of the entire county to a partial county consisting of the municipalities 

identified by the Commonwealth of Pennsylvania. Currently excluded areas will be 

designated in a future round of final designations. Additional information and analysis 

regarding this area is contained in the PA TSD that accompanies this action in the section 

of the TSD that discusses the Warren PA Nonattainment Area. 

3.2.4. EPA Region 4

3.2.4.1. Campbell-Clermont Counties, KY-OH Area

Comments regarding this area are addressed in section 3.2.9.1

3.2.4.2. Nassau County, FL Area

Comment: One commenter believes the proposed nonattainment designation is not 

appropriate because the commenter believes that the data used to make the determination 

is not representative of ambient concentrations of SO2. As described below, there are 

technical problems with the location of the ambient monitoring station and the data 

validation process. At this time Nassau County should be designated as “unclassifiable”

and a more suitable monitoring station should be selected for determination of the 

county's attainment status.

Specifically, the commenter expresses concerns that SO2 emissions from a nearby 

wastewater treatment plant and diesel emissions from truck traffic on an adjacent 

driveway impact the Nassau County monitoring site operated by the State of Florida, and 

that it is not representative of ambient air. The commenter also comments that the data 

from the Nassau County monitor should not be considered valid because the data from a 

nearby monitor operated by Rayonier “differ substantially” from the Nassau County 

monitor data.

EPA’s Response: EPA disagrees with the commenter. The State of Florida submitted 

recommendations for SO2 designations which included certified data from an approved 

monitoring plan for the Nassau County area. In addition, the State performed air quality 

modeling for that area to support its recommended nonattainment boundary. In our 

February 6, 2013, letter to the State, EPA did not propose to modify Florida’s 

recommended boundary, and agreed with the State’s technical analysis for the area.
Page 18 of 63

Regarding the suitability of Florida’s SO2 monitoring station in Nassau County, FL, EPA 

disagrees with the commenter that the Nassau County monitoring data should be 

considered invalid. The State of Florida has operated the monitor in accordance with all 

of the requirements of 40 CFR Part 58, and has certified to EPA that the data is accurate 

and complete. After reviewing the nearby sources, EPA believes that the wastewater 

treatment plant and nearby truck traffic are not significant sources of SO2 emissions, and 

that the monitor is properly sited and is representative of ambient air. EPA also does not 

agree that the data discrepancies observed between Rayonier’s SO2 monitoring site and 

Florida’s SO2 monitoring site should invalidate Florida’s monitoring data. Since the 

Rayonier monitoring data was not collected using an EPA approved Quality Assurance 

Project Plan, the data do not meet the quality assurance requirements of 40 CFR Part 58.

Therefore, based upon the above discussion, EPA believes that the appropriate response 

is to agree with the State’s recommendation and initially designate a portion of Nassau 

County, FL as nonattainment. We will designate currently excluded areas in a future 

round of final designations. See EPA’s TSD for this area for more rationale on why the 

nonattainment area designation is appropriate for this area.

3.2.4.3. Sullivan County, TN Area

Comment: The TSD defines a portion of Sullivan County which consists of a 4.3 

kilometer radius circle centered on a point within the Eastman Chemical Company 

facility. The TSD states that this circle encompasses the Eastman facility as well as the 

one violating monitor in the County. The TSD also states that this boundary encompasses 

two local SO2 sources, AFG Industries and Domtar Paper Company. In fact, it appears 

the location of the Domtar facility governs the size (4.3 kilometer radius circle) of the 

proposed boundary. Table 3 in the TSD lists AFG as emitting 49 tons per year of SO2 and 

Domtar emitting 892 tons per year, based on the 2008 National Emissions Inventory.

It is Eastman’s understanding that the AFG facility has ceased operation and that the 

Domtar facility does not emit SO2. The commenter’s review of the 2008 NEI found on 

EPA’s website showed no SO2 emissions from the Domtar facility. Given that inclusion 

of these facilities results in a larger non-attainment area, Eastman requests the boundary 

be re-defined to be centered on Eastman’s predominant sources of SO2 (coal-fired 

powerhouses) and have a radius large enough to encompass the violating monitor. This 

would result in an area defined by a circle having its center at the B-253 power house 

coordinates 36.5186 N; 82.5350 W and having a 3-kilometer radius.

The Commenter contends that this boundary will ensure that the only significant source 

of SO2 emissions (Eastman) in the vicinity is evaluated for control measures that can be 

included in an attainment demonstration for the area and that the plan will ensure that the 

air quality at the location of the violating monitor (Ross N Robinson) as well as the other 

long-term monitor in the area (Meadowview) is predicted to meet the NAAQS. Note that 

the requested boundary encompasses both monitors mentioned above.

EPA’s Response: EPA has evaluated this additional information and considered it for 

the final determination for the initial boundary for this area. Based on this information 
Page 19 of 63

and a revised recommendation from the State of Tennessee (which is consistent with 

Eastman’s recommendation), EPA has revised the boundary for the final initial 

nonattainment area for Sullivan County. EPA will designate currently excluded areas in 

a future round of final designations. Please see the TSD for the Sullivan County, TN 

Area for the updated boundary. 

3.2.5. EPA Region 5

3.2.5.1. Lemont, IL Area

Comment: Citizens Against Ruining the Environment (CARE) and the Respiratory 

Health Association (RHA) generally support the preliminary determinations regarding 

Illinois regions that do not attain the 2010 SO2 NAAQS based on monitored air quality 

data. Because of the number of human receptors, there is an urgent public health 

justification for IL EPA and U.S. EPA to plan for and achieve attainment as soon as 

possible, without waiting until 2017. 

EPA’s Response: EPA appreciates the support from CARE and RHA for promulgating 

nonattainment designations for the Lemont and Pekin areas. While the attainment date is 

not directly addressed in this rulemaking regarding designations, the promulgation of 

nonattainment designations will trigger nonattainment planning requirements that will 

require Illinois to develop a plan to achieve attainment as expeditiously as practicable but 

no later than five years after the area becomes designated nonattainment.

Comment: Specifically as to the Lemont non-attainment area, CARE and RHA assert 

this non-attainment area includes at least the three Townships in the Illinois 

recommendation and the U.S. EPA response. CARE and RHA also concur that the 

stationary sources of air emissions contributing to this non-attainment include at least the 

Will County coal-fired power plant, the Citgo Refinery and Oxbow Calcining, all of 

which are in an industrial corridor immediately to the west and southwest of the Lemont 

monitor.

EPA’s Response: EPA appreciates this support for the proposed nonattainment area 

boundaries.

Comment: Oxbow Calcining is the closest SO2 source to the Lemont monitor. Both

IL and U.S. EPA assert Oxbow Calcining causes and contribute to non-attainment with 

the 2010 SO2 NAAQS. Yet, there is no federally enforceable annual SO2 emission limit 

in the Oxbow air permit. 

EPA’s Response: At issue here is what area is violating or contributing to violations at 

the Lemont monitor, and this comment implicitly supports EPA’s proposal to include 

Oxbow Calcining in the nonattainment. The designation of nonattainment areas triggers 

nonattainment planning requirements, and comments regarding the presence or absence 

of acceptable emission limits are more germane to the process of Illinois developing its 

nonattainment plan and EPA rulemaking on that plan.
Page 20 of 63

Comment: In characterizing the sources that cause or contribute to non-attainment in the 

Lemont area, both U.S. EPA and IL EPA focus on three· contiguous sources in an 

industrial corridor to the west and southwest of the Lemont monitor. However, there is a 

fourth facility in this same corridor, the Seneca Petroleum facility, that was not 

referenced in this source assessment.

EPA’s Response: According to the 2008 NEI, the Seneca Petroleum facility either does 

not exist or emits less than 100 tons per year. In any case, this facility is within the 

nonattainment area that EPA is promulgating, based on the contributions of other nearby 

facilities, irrespective of the emission level of this facility.

Comment: Midwest Generation ("MWG") operates coal-fired power plants in the 

Lemont non-attainment area (the Will County facility) and the Pekin non-attainment area 

(the Powerton facility). These facilities are identified by IL EPA and U.S. EPA as being 

major sources that cause and contribute to SO2 non-attainment in the Lemont and Pekin 

areas. Midwest Generation also operates a coal-fired power plant in Joliet, immediately to 

the south of the Lemont non-attainment area, which today is a significantly larger SO2

source than its Will County counterpart. Today, none of these coal-burning facilities 

employ flue gas desulfurization pollution control equipment. None of the facilities has (or 

ever had) a Title 5/CAAPP operating permit; in fact, the last effective operating permits 

for these facilities were issued by Illinois in the mid-1990's as federally enforceable state 

operating permits. All of these facilities are subject to an enforcement case initiated by 

the United States of America and the State of Illinois for undertaking major modifications 

without undergoing new source review (United States of America and the State of Illinois 

and Citizens Against Ruining the Environment v. Midwest Generation, LLC, Edison 

Mission Energy and Commonwealth Edison Company, No. 09-5277, United States 

District Court, Northern District of Illinois, Eastern Division; CARE is a PlaintiffIntervener in this case).

EPA’s Response: Again, comments regarding the presence or absence of acceptable 

emission limits are more germane to the process of Illinois developing its nonattainment 

plan and EPA rulemaking on that plan.

Comment: Joliet, with a population of 148,402, is downwind of two large SO2 sources –

Midwest Generation’s Joliet plant and the Exxon-Mobil refinery – that Illinois discounted 

as contributing to the monitored NAAQS exceedances in Lemont, but which RHA and 

CARE assert must be included in any credible analysis of regional SO2 ambient air 

conditions and contributing sources.

CARE and RHA question whether the boundaries of the Lemont nonattainment area are 

expansive enough, and whether there are other stationary sources that are significantly 

contributing to nonattainment. To ensure that the nonattainment area is being accurately 

defined, CARE and RHA assert that an additional monitor should be installed to assess 

ambient air conditions to the south of the existing boundary of the proposed 

nonattainment area.
Page 21 of 63

CARE and RHA also submitted information developed by Sierra Club in support of a 

filing before the Illinois Pollution Control Board against Midwest Generation. This 

information includes modeling conducted by Sierra Club based on allowable emissions 

from Midwest Generation’s Joliet plant, indicating a violation east southeast of the 

facility. CARE and RHA state that Sierra Club used modeling to assess the impact of the 

Joliet plant in the absence of monitoring data that precisely delineates conditions 

downwind. CARE and RHA then assert that there does not appear to be a basis for a 

southern boundary of the Lemont area that neatly excises the contributions of the Joliet 

facility and excludes Joliet from the nonattainment area.

EPA’s Response: The comments from CARE and RHA provide no information on 

impacts of the Midwest Generation’s Joliet plant on the violation recorded in Lemont. 

The attached material from Sierra Club references maps showing a distribution of 

impacts of the Joliet plant, but these maps were not included in CARE and RHA’s 

comments. The only location specifically addressed in these comments is east southeast 

of the facility, which is a significant distance from Lemont. Furthermore, no analysis is 

provided to indicate that high impacts at the Lemont monitor from the Joliet facility are 

occurring at a time when the Lemont monitor is recording high concentrations of SO2. 

CARE and RHA’s comments also do not provide evidence that the Exxon Mobil refinery 

contributes to violations at the Lemont monitor. To the contrary, pollution rose 

information provided with Illinois’ recommendations indicates that violations 

predominantly occur with west winds. Since these two facilities are considerable 

distance from the Lemont monitor, and since CARE and RHA have provided no evidence 

that these facilities contribute to the violations recorded at the Lemont monitor, EPA 

continues to believe that the proposed nonattainment area boundaries appropriately 

exclude these two facilities.

The comments of CARE and RHA suggest that EPA take one of three options: 1) 

designate a larger nonattainment area that includes the area of violation and contributing 

sources both in Lemont and in Joliet, 2) designate the Joliet area as well as the Lemont 

areas as separate nonattainment areas, or 3) designate the Lemont area as nonattainment 

and require further monitoring to assess whether the Joliet area is violating the standard. 

For reasons given above, EPA believes that the proposed Lemont nonattainment area 

boundaries are the appropriate boundaries for this area. EPA is not currently acting on 

other areas such as the Joliet area. EPA has posted a strategy paper on the internet that 

envisions requiring further analysis of areas like the Joliet area, as CARE and RHA 

suggest. However, action on the Joliet area is not part of this rulemaking, which in 

Northeast Illinois addresses only the Lemont area.

Comment: RHA and CARE request clarification on the construction permit standards 

that will be imposed on a new SO2 source in the newly designated nonattainment areas 

(which would also apply to major modifications to existing sources).

RHA and CARE also request SO2 emissions information provided by the Citgo Refinery, 

which is operating subject to a federal Consent Decree. It appears that Citgo's SO2 
Page 22 of 63

emissions have been reduced exponentially. Can U.S. EPA characterize Citgo's SO2

emissions over the past five years, and confirm this significant downward trend?

EPA’s Response: These comments are not germane to this rulemaking on designations. 

Nonattainment planning requirements will be addressed separately. Illinois will evaluate 

emissions from the Citgo Refinery as part of it nonattainment planning process.

(See also a comment and response presented below concerning both the Lemont and 

Pekin areas.)

Comment: The ExxonMobil Joliet Refinery supports the EPA's concurrence with the 

Illinois EPA's recommendation that Will County be divided, and to ask that all 

townships, other than Lockport, and DuPage townships be designated as attainment or 

unclassifiable as they do not have a significant impact on the Cook County S01 monitor 

AQS ID # 17-031-1601 located at 729 Houston, Lemont, which is located in Cook 

County just across the Will County boundary.

EPA’s Response: EPA appreciates ExxonMobil’s support of the Lemont nonattainment 

area. However, no action is being taken on the remainder of Will Country in this rule 

making, so the remainder of Will Country will not receive an attainment or unclassifiable 

designation. 

3.2.5.2. Pekin, IL Area

Comment: Both the Illinois Environmental Regulatory Group (IERG) and Ameren 

submitted comments urging EPA to exclude Hollis Township from the nonattainment 

area based on low frequency of winds coming from that direction, particularly during 

hours of violating when SO2 concentrations exceeded the standard. IERG states that the 

meteorology analysis submitted by IEPA is not supportive of the inclusion of this area. 

They provided two composite photos, one of a wind rose from IEPA layered on a map 

from IEPA of the area showing the locations of the facilities and the other of a pollution 

rose from IEPA layered on that same map. IERG agrees with IEPA’s assessment that 

sources to the west and southwest most likely contribute to the exceedance. IERG 

compared wind direction to hours of SO2 exceedances from 2007 to 2011 and provided 

percentages of the wind direction during exceedances. They found that the wind 

direction was variable 3.7% of the time, from the NW 0.4%, and not from the other 

northerly directions. 

Ameren stated that their E.D. Edwards facility is almost directly north of the monitor and 

that wind from the north accounts for less than 5% of the total wind direction occurrences 

and therefore the probability of the facility causing an exceedance is low. Ameren also 

states that 99% of the violating SO2 values at that monitor occurred when winds were 

from the South –Southwest to West-Northwest with the majority from the West and 

West-Southwest. Ameren stated that the wind speeds were usually greater that 10 mph 

during exceedances, which points to the facilities with short stack heights in the west. 

Ameren believes that emission levels are not the only factor to be considered, and EPA 
Page 23 of 63

should look at the meteorology of a monitor and the actual locations of facilities, stack 

heights, stack flow and temperature, and other relevant operating characteristics of the 

facilities. Ameren also provided a pollution rose in graph form and a table of hourly SO2 

exceedance from 2008-2010 with the associated wind direction and speed.

EPA’s Response: EPA believes that winds come from the direction of E.D. Edwards 

with sufficient frequency that the substantial emissions of this facility warrant being 

considered to contribute to the violation in Pekin. Ameren states that the winds from the 

north account for less than 5 percent of the total wind occurrences. An even distribution 

of winds among 16 wind directions would mean about 6 percent of the winds from each 

direction, so this does not signify particularly low frequency. As shown in IEPA’s initial 

recommendation, of the sixteen wind directions, eleven of the directions occur 3 to 6% of 

the time. Four of the directions occur 6 to 9% of the time with the most frequent 

southerly direction occurring less than 15% of the time. Thus, winds coming from the 

direction of E.D. Edwards plant toward the Pekin monitor occur with sufficient frequency 

that the facility has significant potential to contribute to the monitored violations.

Most of IERG’s and Ameren’s comments focus on winds during hours when SO2

concentrations at the Pekin monitor exceeded the level of the standard. EPA agrees that 

the winds for the Pekin Nonattainment area are most frequently from the south and west 

wind directions during times of exceedances. However, this statement does not answer 

the question of whether winds from the direction of the E.D. Edwards plant occur with 

sufficient frequency to conclude that the plant contributes to the violation. 

In response to IERG’s and Ameren’s presentation of average wind directions during 

hours of SO2 exceedances for 2008 to 2010, EPA conducted a similar review. EPA 

examined the average of two-minute wind direction samples instead of an hourly sample 

to better evaluate variable winds. From this review, EPA identified numerous occasions 

when exceedances occurred during times with generally northerly winds. For example, 

EPA found that on May 9, 2010 at 14:00, the SO2 value was monitored at 97 ppb with an 

hourly average wind direction of 343 degrees (NNW) with a wind speed of 4 mph. The 

facility likely cause the greatest impact from this direction is the Ameren E.D. Edwards 

facility. Another example was an exceedance of 109 ppb on April 21, 2010 at 15:00, 

when the wind was blowing at 5 mph at 317 degrees. This exceedance, with northwest 

winds, suggests significant contributions from either or both of the facilities in that 

direction, i.e., either or both of E.D. Edwards and the Aventine Renewable Energy 

facility in Pekin Township. 

Wind data supplied by Ameren showed an exceedance on January 17, 2010 of 89 ppb. 

The wind direction is shown to vary during this hour from 10 to 40 degrees, which 

suggests a significant contribution to the exceedance from the Ameren E.D. Edwards 

facility. Ameren’s data also show several instances of variable wind direction and calm 

winds with exceedances associated with the time period. With calm winds, significant 

contributions are likely to arise from nearby facilities with significant emissions in 

several directions from the monitor, including in particular in the direction from which 

the E.D. Edwards plant would contribute. 
Page 24 of 63

When winds are variable, a proper analysis often requires assessing the variety of wind 

directions observed during the pertinent period. For example, on April 9, 2009, an 

exceedance of 119 ppb was recorded starting at 10:00. The hourly wind data showed the 

average wind direction to be 233 degrees. However, in looking at just a twenty minute 

period of the actual two minute rolling averages, from 10:35 to 10:55, the wind direction 

shifted quite frequently, as seen in the table below: 

Local Time Wind Direction (Degrees)

10:35 347

10:36 354

10:37 325

10:38 255

10:39 229

10:40 239

10:41 237

10:42 238

10:43 244

10:44 204

10:45 168

10:46 155

10:47 155

10:48 161

10:49 108

10:50 27

10:51 351

10:52 348

10:53 341

10:54 343

10:55 2

Several of these data points are in the northerly direction of the facility, suggesting that 

the E.D. Edwards facility was contributing to the exceedance during several portions of 

the hour. 

These two minute data are two minute averages of wind direction and speed that are 

rolling every minute, meaning there are 60 two minute averages every hour. These data 

show a more accurate picture of the wind patterns during a recorded hour. The data 

allow for the change of wind direction during the hour to be observed instead of basing 

the entire hour on one average or one reading. The table below shows that looking 

beyond a single wind direction reading shows several additional instances of possible 

contribution to the exceedances from the direction of the Ameren facility. The table 

below looks at the two minute data during hours of exceedance. The number of 

occurrences is the number of rolling two minute data during the hour that were between 

315 (Northwest) and 11 (North by East), which were used to indicate potential for 

significant contribution from the E.D. Edwards facility. The total possible number of 

occurrences during an hour is 60 due to the average rolling every minute. 
Page 25 of 63

Date Hour

Number of 

Occurrences

Exceedance 

Value

4/9/2009 10:00-11:00 8 78

5/31/2009 11:00-12:00 5 144

5/31/2009 12:00-13:00 14 112

6/9/2009 12:00-13:00 4 137

6/9/2009 13:00-14:00 3 83

7/15/2009 12:00-13:00 1 84

7/31/2009 9:00-10:00 5 76

10/4/2009 14:00-15:00 3 98

1/17/2010 1:00-2:00 7 89

4/21/2010 15:00-16:00 25 109

5/9/2010 12:00-13:00 9 104

5/9/2010 14:00-15:00 39 97

10/1/2010 13:00-14:00 15 97

3/21/2011 12:00-13:00 9 126

5/7/2011 13:00-14:00 1 76

8/8/2011 17:00-18:00 24 95

9/25/2011 13:00-14:00 5 104

On each of these occasions, the E.D. Edwards facility was likely contributing to the 

exceedance during at least some portion of the hour.

This review suggests that, in addition to winds in the direction from the E.D. Edwards 

facility toward the Pekin monitor being common in general, winds in this direction also 

occur periodically on occasions when the Pekin monitor shows SO2 concentrations to 

exceed the standard. Furthermore, winds in this area are frequently variable, such that a 

significant fraction of the contribution to exceedances could be arising from the E.D. 

Edwards facility on these occasions as well. Given the quantity of emissions from this 

facility (approximately 11,000 tons per year), EPA believes that winds blow from this 

facility toward the Pekin monitor with sufficient frequency, including specifically on 

days with high monitored concentrations, to warrant this facility being considered to 

contribute to violations at the monitor. 

Comment: Midwest Generation ("MWG") operates coal-fired power plants in the 

Lemont non-attainment area (the Will County facility) and the Pekin non-attainment area 

(the Powerton facility). These facilities are identified by IL EPA and U.S. EPA as being 

major sources that cause and contribute to SO2 non-attainment in the Lemont and Pekin 

areas. Midwest Generation also operates a coal-fired power plant in Joliet, immediately to 

the south of the Lemont non-attainment area, which today is a significantly larger SO2

source than its Will County counterpart. Today, none of these coal-burning facilities 

employ flue gas desulfurization pollution control equipment. None of the facilities has (or 

ever had) a Title 5/CAAPP operating permit; in fact, the last effective operating permits 
Page 26 of 63

for these facilities were issued by Illinois in the mid-1990's as federally enforceable state 

operating permits. All of these facilities are subject to an enforcement case initiated by 

the United States of America and the State of Illinois for undertaking major modifications 

without undergoing new source review (United States of America and the State of Illinois 

and Citizens Against Ruining the Environment v. Midwest Generation, LLC, Edison 

Mission Energy and Commonwealth Edison Company, No. 09-5277, United States 

District Court, Northern District of Illinois, Eastern Division; CARE is a PlaintiffIntervener in this case).

EPA’s Response: This information supports the proposed nonattainment area 

boundaries. Illinois will need to consider the need for further control of these facilities as 

it prepares its nonattainment area plans.

3.2.5.3 Detroit, MI Area

Comment: U. S. Steel requested that USEPA include the portions of Monroe County that 

include the DTE Monroe Station in the Detroit nonattainment area. U.S. Steel observed 

that this power plant is a significant source of SO2. U.S. Steel observed that before 2009, 

this plant was the “second largest coal-fired power plant in the nation.” U.S. Steel 

asserted further that air quality improvements following installation of scrubbers on two 

of the four units in 2009 “suggest a strong correlation between [emissions at Monroe 

Station and Detroit air quality].” U.S. Steel quoted EPA’s rationale for excluding 

Monroe Station from the nonattainment area, and objects that “the data support a finding 

that if similar controls were installed on the two remaining units, . . . then the [violating 

monitor] would most likely demonstrate attainment.” 

U.S. Steel submitted a presentation prepared by Mike Lebeis of DTE Energy. This 

presentation describes a review of the seasonal frequency of elevated SO2 concentrations 

at the critical monitor in Detroit (at the Southwest High School, or SWHS) and notes 

significant changes in SO2 emissions in Southeast Michigan during the study period, in 

particular the installation of scrubbers on Units 3 and 4 in November and June 2009, 

respectively, and the temporary shutdown of the Detroit area U.S. Steel facility from 

November 2008 to August 2009. The presentation highlights the fact that only seven 

occasions of concentrations above 75 ppb occurred in 2009, during none of which was 

U.S. Steel operating. The presentation includes a slide entitled “Summary Findings –

Hypothesis” which speculates that high SO2 concentrations arise from a combination of 

impacts from regional sources and local sources, but no analyses are presented that assess 

the relative impacts of regional versus local sources. Nevertheless, U.S. Steel 

characterizes the presentation as “clearly [suggesting] that that both regional SO2 sources 

and local SO2 sources are the reasons for elevated SO2 readings at the SWHS monitor. 

Furthermore, the analysis indicates that since 2010, there has been a noticeable drop in 

the number of hours per year that SO2 exceeds 75 ppb at the SHWS monitor.” According 

to the Lebeis presentation, this would suggest that the lower readings at the SWHS 

monitor are attributable at least in part to the improvements at the Monroe Power Plant. 

This presentation also states that in 2009, the only hours when the NAAQS was exceed at 
Page 27 of 63

SWHS occurred in the Spring when US Steel operations were curtailed,’ suggesting that 

U.S. Steel, a local source, does not significantly impact the SWHS monitor.

For these reasons, U. S. Steel encouraged USEPA and MDEQ to include portions of 

Monroe County to include Monroe Station, a large SO2 source located upwind of the 

SWHS monitor, as part of the “Wayne County” nonattainment area.

EPA’s Response: Neither in its comments nor in its attached presentation did U.S. Steel 

provide any analysis of the impacts of Monroe Station in relation to the impacts of other 

sources that are closer to the monitor. Instead, the evidence U.S. Steel presents must be 

considered anecdotal, reflecting the frequency of elevated SO2 concentrations in 

conjunction with information about variations in emission rates. The presentation itself 

attributes the relatively low number of exceedances of 75 ppb recorded in 2009 to the 

relatively cool temperatures recorded that year. Indeed, the variations in the frequency of 

exceedances in other years may simply reflect variations in meteorology. Other data in 

the Lebeis presentation, namely the fact that few exceedances occur when U.S. Steel is 

shutdown and more exceedances occur when U.S. Steel is operating, suggest support for 

a conclusion that U.S. Steel is a significant contributor to the exceedances, but the 

influence of meteorological variations is too important to be able to use these statistics to 

reach either this or U.S. Steel’s conclusion.

The Lebeis presentation reports that 2010 has the greatest number of exceedances of the 

75 ppb standard, with moderately low numbers of exceedances occurring in 2011 and 

2012. U.S. Steel asserts that the low numbers of exceedances in 2011 and 2012 reflect 

the impact of controls at Monroe Station, but U.S. Steel offers no explanation as to why 

the high number of exceedances in 2010, which also came after the implementation of 

controls at two units of Monroe Station, should not be considered evidence that these 

controls had no impact on concentrations at SWHS. Indeed, considering the high 

frequency of exceedances in 2010 according to U.S. Steel’s reasoning, one would infer 

that the emission reductions at Monroe Station have minimal effect and the resumption of 

emissions at U.S. Steel has significant effect, a conclusion that is diametrically the 

opposite of U.S. Steel’s conclusion from examining 2011 and 2012 data. EPA finds a 

more plausible conclusion to be that U.S. Steel’s comments, and the Lebeis presentation 

that they rely on, are simply unreliable evidence as to the contribution of Monroe Station. 

EPA agrees that south winds are common on days with elevated concentrations at the 

SWHS monitor. However, EPA must evaluate further whether Monroe Station, located 

approximately 54 kilometers from the monitor, should be considered to be a nearby 

source that contributes to the violations recorded at the monitor.

U.S. Steel conceded that Monroe Station would not be considered a source that is “local” 

to the SWHS monitor. Under Clean Air Act section 107, nonattainment areas, in addition 

to including the areas violating the standard, are to include the nearby sources that 

contribute to the violation. U.S. Steel does not address criteria for judging a source to be 

nearby, but U.S. Steel implicitly concedes that Monroe Station could reasonably be 

considered not to be nearby the SWHS monitor.
Page 28 of 63

U.S. Steel also does not address the significance of the data showing monitored design 

values below the SO2 standard at the Allen Park monitor, a monitor which is somewhat 

to the southwest of the SWHS monitor, closer to Monroe Station. While these data do 

not answer the question of whether Monroe Station contributes to concentrations at either 

location, these data do indicate that most of the SO2 monitored at the SWHS monitor is 

being contributed from more local sources. Based on the analysis described in the TSD, 

EPA continues to believe that Monroe Station is not a nearby source that contributes to 

the violation at the SWHS monitor.

3.2.5.4 Terre Haute, IN Area

Comment: Indiana agrees with the inclusion of Fayette Township in the Terre Haute 

nonattainment area, but disagrees with the inclusion of Otter Creek Township because the 

population for that township is low and there are no sources of SO2.

EPA’s Response: See Terre Haute, IN portion of the Indiana TSD.

3.2.5.5 Richmond, IN Area

Comment: Indiana submitted a recommendation that Wayne County, IN should be 

excluded from this round of designations because the monitor in Wayne County has 

certified, quality assured data showing that it is not violation the 2010 SO2 Standard 

based on the 2010-2012 design period with a design value of 66 ppb.

EPA’s Response: Because there are no monitored violations for the Richmond, Indiana 

area, no action is currently being taken on this area.

3.2.5.6 Oneida County, WI Area

Comment: EPA proposed one SO2 nonattainment area for the State of Wisconsin. This 

is the area that was initially recommended in a letter to EPA Region 5 on May 26, 2011. 

On January 23, 2013, however, the source responsible for the elevated S02 

concentrations submitted an application with the WDNR to install a natural gas boiler at 

their facility. Given this development, EPA should delay finalization of the one 

nonattainment designation in Wisconsin at this time. This is the major source of S02 in 

the area and the WDNR believes the area will achieve attainment when the source 

reduces its emissions. Consequently, attainment status should be granted once the cause 

of the nonattainment is removed or reduced.

Regardless of the U.S. EPA's action regarding finalization of the nonattainment 

designation, the remainder of Oneida County should be designated attainment.

U.S. EPA should also designate other areas in Wisconsin attainment now, based on 

emissions and monitoring data.
Page 29 of 63

EPA’s Response: EPA is currently acting on designations for areas currently monitoring 

violations of the SO2 NAAQS. See the Wisconsin TSD for further discussion of this 

comment. 

3.2.5.7 Marshall, WV Area (previously called Wheeling, WV-OH)

Comments regarding this area are addressed in section 3.2.9.3

3.2.6. EPA Region 6

3.2.6.1 St. Barnard Parish, LA

Comment: One commenter described the communities around the plants and refineries 

in St. Bernard Parish as under-served and over-burdened with rising sulfur levels, and 

generally expresses support for a nonattainment designation for St. Bernard Parish. 

EPA’s Response: EPA acknowledges the commenter’s support for a nonattainment 

designation for St. Bernard Parish.

Comment: One commenter believes that the rising sulfur levels in St. Bernard Parish are 

a result of the pollution allowed by Title V air permits issued to stationary sources, 

emissions from plants and refineries that have been “grandfathered,” and from 

unpermitted sulfur emissions. The commenter also states that expansions, modifications, 

and variance exemptions that have been approved by the Louisiana Department of 

Environmental Quality (LDEQ) for the Rain CII facility and other plants and refineries 

without appropriate review or without providing public notice have also resulted in 

increased pollution and unacceptable and unhealthy air quality. 

EPA’s Response: EPA agrees with the commenter that stationary sources in the area 

appear to be responsible for much of the elevated SO2 levels in St. Bernard Parish (see 

our TSD found in Docket ID No. EPA-HQ-OAR-2012-2033). The determination of 

whether it will be necessary to establish federally enforceable emission limits more 

stringent than those currently in place for stationary sources in the area to achieve 

attainment of the standard in St. Bernard Parish will be made through the nonattainment 

State Implementation Plan (SIP) process. The requirement to develop a nonattainment 

SIP is triggered by the nonattainment designation. The nonattainment SIP, itself, is 

outside the scope of the designations process. LDEQ will have to develop this SIP in 

accordance with CAA sections 172 and 191-192, adopting the necessary controls so that 

the area will attain the standard as expeditiously as practicable, but no later than the 

statutory attainment date. Under the CAA, the State must provide the public the 

opportunity to comment on the plan revision and the State must respond to those 

comments before adopting the SIP and submitting it to EPA for approval.

While we acknowledge the commenter’s concern with the potential increase in SO2

emissions resulting from previously approved or proposed source modifications or 

expansions and previously approved variances, we note that this is also outside the scope 
Page 30 of 63

of the designations process. These permitted and potential permitted increases, however, 

are required to be evaluated by LDEQ and taken into account during the development of 

the nonattainment SIP. Specific permitting and variance concerns, however, should be 

raised directly to LDEQ on a permit by permit basis, during the public comment period 

for the proposed permit revision, as LDEQ’s air permitting program has been approved 

by EPA into the Louisiana SIP. Concerns related to public participation with regard to 

proposed source modifications and variance requests should also be raised to LDEQ. 

Comment: The commenter states that the SIP should address the potential increase in 

SO2 emissions resulting from permit applications currently under administrative review,

and from compliance with EPA’s expected Tier 3 mandates and other future regulations. 

The commenter believes that modifications of sources in the area and new regulatory 

mandates expected in the near future should not cost the community what little good air 

is remaining.

EPA’s Response: We acknowledge the commenter’s concerns related to the impact of 

future construction and/or modifications of sources in the area. The federal Clean Air Act 

requires that the new nonattainment SIP include a nonattainment New Source Review 

permitting program that would apply in the St. Bernard Parish nonattainment area. All 

new major stationary sources and major modifications in the nonattainment area must 

offset their new emissions so there is no net increase in SO2 emissions in St. Bernard 

Parish. However, evaluation of potential SO2 emissions increases resulting from 

applications under the New Source Review permitting program is outside the scope of the 

designations process. 

Furthermore, with respect to the commenter’s concern with the potential impact of source 

compliance with future federal air pollution regulations, we note that this is also outside 

the scope of the designations process and the nonattainment SIP development process. If 

compliance with any existing or future federal regulations will cause increases of SO2 in 

the future, the LDEQ must take these increases into consideration while developing the 

nonattainment SIP and adopt control measures as needed to attain the standard as 

expeditiously as practicable, but no later than the statutory attainment date. However, we 

note that before promulgating any new federal air pollution regulations, EPA develops 

technical, economic, and environmental analyses that are available for review and 

comment during a public notice and comment period of at least 30 days after a new 

federal regulation is proposed. This may provide an appropriate venue for the commenter 

to raise concerns regarding potential increases in SO2 emissions resulting from 

compliance with those regulations.

Comment: One commenter believes that the communities in St. Bernard Parish should 

have an opportunity to attend public information sessions and provide input before any 

SIP decisions are made. The commenter believes that appropriate controls are necessary 

to maintain the balance between residential neighborhoods and heavy industrial land use. 

The commenter states that the SIP should: protect public health and safety in St. Bernard 

Parish by requiring all major sources to install technology that results in the lowest 

achievable emission rates; require emission reductions beyond what may already be 
Page 31 of 63

scheduled; require the operation of air monitors along the perimeter/fence-line of sources 

since monitored violations at fixed ambient air monitors can be dependent on wind 

direction; require the operation of current ambient air monitors beyond SIP and EPA 

consent decree timelines (in particular for the Valero Energy air monitor); and require 

operation of additional ambient air monitors (in particular along the west bank of the 

Mississippi River) where residents have reported experiencing adverse health effects 

when the wind blows opposite the Chalmette Vista monitor and carries emissions from 

sources in St. Bernard Parish to Orleans Parish. The commenter believes that other 

solutions at all major sources, docks, and terminals in St. Bernard Parish include more 

stringent pollution controls, meaningful enforcement and surveillance, a residents-based 

community benefits agreement with each industry, and the dedication of any penalties 

toward local projects that support public health, local jobs, and community resettlement. 

EPA’s Response: While issues related to the development of nonattainment SIPs for the 

1-hour SO2 NAAQS are outside the scope of the designations process, we note that CAA

section 172(c) describes the general requirements for nonattainment SIPs. Nonattainment 

SIPs generally contain requirements such as (but not limited to): reasonably available 

control measures (including reductions in emissions from existing sources in the area) 

and provide for attainment of the NAAQS, enforceable emission limitations, and means 

or techniques as necessary or appropriate to provide for attainment of the 1-hour SO2

standard. All new major sources and major modifications will be required to install 

technology that results in the lowest achievable emission rate. As the state air pollution 

control agency in Louisiana, LDEQ will have the responsibility to develop this SIP and 

submit it to EPA for approval. Federal regulations require states to provide reasonable 

notice and hold a public hearing on a draft SIP and respond to all public comments 

received before the SIP is submitted to EPA for approval. In addition, EPA provides

public notice and an opportunity for public comment before finalizing its action to 

approve or disapprove a SIP. As such, we expect that the communities in St. Bernard 

Parish will have sufficient opportunity to provide input before EPA takes final action on 

the nonattainment SIP. 

With respect to the commenter’s monitoring concerns, the EPA requirements for the 1-

hour SO2 National Ambient Air Quality Standard revised on June 2, 2010, can be found 

at http://www.epa.gov/airquality/sulfurdioxide/actions.html. The final 1-hour SO2

NAAQS rule requires a minimum of three SO2 monitors for any Core-based Statistical 

Area (CBSA) with a calculated Population Weighted Emissions Index (PWEI) value 

equal to or greater than 1,000,000. A PWEI uses population and emissions inventory data 

at the CBSA level to assign required monitoring for a given CBSA, with population and 

emissions being obvious relevant factors in prioritizing numbers of required monitors. 

The final 1-hour SO2 NAAQS rule also requires a minimum of two SO2 monitors for any 

CBSA with a calculated PWEI value equal to or greater than 100,000, but less than 

1,000,000. For any CBSA with a calculated PWEI value equal to or greater than 5,000, 

but less than 100,000, a minimum of one SO2 monitor is required within that CBSA. In 

the final SO2 NAAQS rule, EPA stated that the monitors required within these 

breakpoints would provide a reasonable minimum number of monitors in a CBSA that 

considers the combination of population and emissions that exist in a CBSA. Based on 
Page 32 of 63

the SO2 monitoring network requirements in the final 1-hour SO2 NAAQS rule, no 

additional SO2 monitors are required on the west bank of the Mississippi River in Orleans 

Parish nor along the fence-line of stationary sources in St. Bernard Parish. 

We note at this time, separate from the designations process, the EPA is evaluating the 

overall implementation strategy for the SO2 standard, including evaluation of regulatory 

air monitoring requirements. Opportunities for additional public input will be available as 

necessary changes to existing rules, if any, and guidance are developed. Additional 

information on EPA’s SO2 implementation plans can be found at: 

http://www.epa.gov/oaqps001/sulfurdioxide/implement.html and 

http://www.epa.gov/oaqps001/sulfurdioxide/pdfs/20130207SO2StrategyPaper.pdf. 

Furthermore, whenever a state’s annual monitoring network plan proposes monitoring 

network modifications, a public comment opportunity is furnished by either the State or 

EPA. 

As further explained in a separate response, the Valero air monitor the commenter 

references was required by a 2010 consent decree between the facility and EPA to settle

CAA violations. This monitor is operated and maintained by the facility, and is not a 

regulatory air monitor. The requirements for operation of the Valero air monitor were 

established by the consent decree and because it is a non-regulatory monitor, the 

requirements for its operation are outside the scope of the designations processes. 

Comment: The commenter expresses concern that the “SIP timeline of 2018” may be too 

late for St. Bernard Parish’s residents who report having a negative quality of life and 

health effects as a result of flaring events.

EPA’s Response: While issues related to the deadline for attainment are outside the 

scope of the designations process, the commenter appears to be referring to the statutory 

deadline for areas designated nonattainment for the 1-hour SO2 NAAQS to attain the 

standard. CAA section 191(a) requires states to develop and submit nonattainment SIPs

to EPA within 18 months of the effective date of an area’s nonattainment designation, 

demonstrating that the affected area will attain the standard by the applicable statutory 

attainment date. Under CAA section 192(a), areas designated nonattainment with respect 

to the primary SO2 NAAQS must attain the standard as expeditiously as practicable, but 

no later than 5 years from the date the area was designated nonattainment. We anticipate 

working with LDEQ in the development of the SIP to identify the most expeditious

practicable attainment date and ensure this requirement is met. 

Comment: The commenter expresses support for a nonattainment designation for St. 

Bernard Parish, noting that all three major sources in St. Bernard Parish contribute SO2

emissions and both the “Chalmette Vista” and the “Valero” air monitors have multiple 

violations of the 1-hour SO2 standard.

EPA’s Response: EPA acknowledges the commenter’s support for a nonattainment 

designation for St. Bernard Parish.
Page 33 of 63

Comment: The commenter expresses support for a nonattainment designation for St. 

Bernard Parish, noting that the health of people in the community is being negatively 

affected by high concentrations of SO2. The commenter believes that industry has caused 

a disaster that was avoidable, but it will now take a long time for the community to 

recover and the “label” of nonattainment will have a deterring effect on the community’s 

resettlement programs. The commenter states that both Valero Energy and ExxonMobil 

operate several other refineries in other areas using better control technology resulting in 

lower SO2 emissions, and suggests that these companies should be required to make the 

same investment at their facilities in St. Bernard Parish. 

EPA’s Response: EPA acknowledges the commenter’s support for a nonattainment 

designation for St. Bernard Parish. However, development of the nonattainment SIP and 

decisions on what control technology sources in the area must install are outside the 

scope of the designations process. LDEQ is responsible for developing a SIP that 

includes controls for sources in the area and contains an attainment demonstration 

showing St. Bernard Parish will attain the standard as expeditiously as practicable, but no 

later than the statutory attainment date.

Comment: The commenter states that control technology that would reduce emissions 

resulting from plant startup/shutdown due to planned maintenance, unplanned 

malfunctions, and hurricane and other weather related events is available and should be 

required for sources in the area. The commenter states that in August 2012 in preparation 

for Hurricane Isaac, the ExxonMobil Chalmette plant and the Valero Energy Meraux 

plant had planned shutdowns and reported emitting over 46 tons of SO2 and 1,102 pounds 

of SO2 (respectively) from startup and shutdown procedures. The commenter adds that 

while hurricane related events may result in a violation of the 1-hour SO2 NAAQS, this 

goes undocumented because monitoring sites are taken down during hurricanes for safety 

reasons. The commenter believes that industry in St. Bernard Parish should plan ahead 

and be properly equipped for weather related events. 

EPA’s Response: We acknowledge the commenter’s concern with emissions resulting 

from startup, shutdown, and malfunction; however, we note that the determination of 

what control technologies should be required for sources in the area is outside the scope 

of the designations process. As stated in a previous response, LDEQ in the SIP 

development process will determine which sources must install what pollution controls to 

meet applicable emission limits to attain the 1-hour SO2 standard. We encourage the 

commenter to participate during the development of the SIP. Although out of the scope of 

the designations process, we also note that on February 22, 2013, EPA published a notice 

in the Federal Register proposing to take action on a petition for rulemaking filed by the 

Sierra Club on June 30, 2011 (see 78 FR 12460). The petition included interrelated 

requests concerning the treatment of excess emissions in 39 states’ existing SIP rules by 

stationary sources during periods of startup, shutdown, or malfunction. In that proposed 

rulemaking, EPA specifically proposed to determine that Louisiana‘s existing SIP 

includes a number of provisions regarding the treatment of excess emissions during 

periods of startup, shutdown, and malfunction that are inconsistent with the CAA. The 

EPA also simultaneously proposed a SIP call which upon finalization would give 
Page 34 of 63

Louisiana 18 months to correct and submit its revised SIP to EPA. The EPA’s February 

22, 2013 proposed rule intends to ensure states have SIP provisions in place that require 

industrial facilities across the country to follow air pollution rules during times when the 

facility is starting up or shutting down, or when a malfunction occurs. More information 

on EPA’s proposed SIP call on startup, shutdown, and malfunction can be found at: 

http://www.epa.gov/airquality/urbanair/sipstatus/emissions.html.

With regard to the commenter’s concern with potential violations of the 1-hour SO2

NAAQS that may go undetected during hurricane events when ambient air monitors are 

taken down, we note that taking down monitors is routine practice during hurricane 

events in order to prevent damage to expensive monitoring equipment. The monitors are 

only taken down temporarily and usually resume operations promptly following the 

hurricane event. We also note that during and following emergencies, EPA may deploy 

mobile air monitoring equipment to monitor and sample for substances that may be 

present in the environment. The decision whether to deploy these mobile air monitors is 

usually based on the emergency and determined on a case by case basis. Therefore, we 

expect that any major accidental releases of chemicals or emissions into the atmosphere 

that could potentially pose a serious threat to human health would not go undetected. 

Comment: The commenter states that emergency flaring resulting from unplanned 

malfunctions and shutdowns can cause chronic and acute health risks and may violate the 

1-hour SO2 NAAQS. The commenter argues that the ExxonMobil Chalmette refinery and 

the Valero Energy Meraux refinery are major contributors to nonattainment in St. 

Bernard Parish, stating that both the Chalmette Vista and Valero monitoring sites have 

many violations of the 1-hour SO2 NAAQS. The commenter states that the ExxonMobil 

Chalmette refinery in 2010 and 2011, and the Valero Energy Meraux refinery in 2011 

and 2012, emitted more SO2 emissions than what each is permitted to emit. The 

commenter also provides information on unplanned flaring events at both the 

ExxonMobil Chalmette refinery and the Valero Energy Meraux refinery, noting that there 

were monitored violations at the Chalmette Vista and the Valero monitoring sites during 

these events when the wind was blowing away from the sources and toward the monitors. 

EPA’s Response: We agree with the commenter that stationary sources in the area 

appear to be responsible for elevated SO2 levels in St. Bernard Parish, as measured in 

particular at the Chalmette Vista monitor (see our Technical Support Document found in 

Docket ID No. EPA-HQ-OAR-2012-2033). In making our decision to designate St. 

Bernard Parish nonattainment, we considered the three most recent years of certified data 

from regulatory ambient air monitors, as well as certain other factors. However, in 

determining that the St. Bernard Parish area was in violation of the NAAQS for purposes 

of designations, we did not take into consideration any data from the Valero air monitor 

referenced by the commenter, as it is not a regulatory monitor. Although we believe the 

data from the Valero monitor is informational in many respects, the data does not meet 

the requirements in 40 CFR Part 58 Appendices A, C, and E. Because ambient air quality 

data used by the EPA for establishing violations of the NAAQS must meet the 

requirements in 40 CFR Part 58 Appendices A, C, and E, EPA cannot consider data from 
Page 35 of 63

the Valero monitor for purposes of establishing NAAQS violations for designation 

purposes.

Comment: The commenter states that the Chalmette Vista monitor, located north of 

ExxonMobil and Rain CII, demonstrates violations of the 1-hour SO2 NAAQS and shows 

that both sources are major contributors to nonattainment. The commenter notes that 

LDEQ’s 2011 designation recommendations to EPA were based on 2008-2010 air 

monitor data, and states that there have been no significant improvements in monitored 

SO2 concentrations in 2011 and 2012 at the Chalmette Vista air monitor while there has 

been an increase in SO2 concentrations at both the Meraux and Valero air monitors, with 

violations at the Valero air monitor. 

EPA’s Response: As can be seen in the analysis presented in our TSD, which can be 

found in Docket ID No. EPA-HQ-OAR-2012-2033, we agree with the commenter that 

Rain CII and ExxonMobil appear to contribute to the violations recorded at the Chalmette 

Vista monitor. EPA established the 1-hour SO2 standard at a level of 75 parts per billion 

(ppb), based on a 3-year average of the annual 99th percentile of 1-hour daily maximum 

concentrations. In making its designation decisions, EPA must consider the three most 

recent years of certified data from regulatory ambient air monitors, as well as certain 

other factors. Louisiana based its 2011 designation recommendations on 2008-2010 air 

monitoring data because at the time those were the three most recent years for which 

certified air monitoring data was available. Since certified 2011 air monitoring data 

became available by the time EPA proposed its designations in February 2013, EPA 

proposed and is now finalizing its SO2 designation decision for St. Bernard Parish based 

on a violation of the NAAQS established by 2009-2011 data from regulatory air 

monitors. Although in recent years there has been some improvement in the monitored 

SO2 concentrations at the Chalmette Vista monitor, we agree with the commenter that the 

monitor’s 2009-2011 design value of 287 parts per billion (ppb) is significantly above the 

standard of 75 ppb.

Although EPA is designating St. Bernard Parish nonattainment, we note that in making 

that decision EPA did not take into consideration for purposes of establishing NAAQS 

violations any data from the Valero air monitor referenced by the commenter, as it is not 

a regulatory monitor. The Valero monitor is a community air monitoring station that was 

installed by the facility as part of a 2010 consent decree with EPA to settle CAA 

violations, and is operated and maintained by the facility. Although we believe the data 

from the Valero monitor is informational in many respects, the data does not meet the 

requirements in 40 CFR Part 58 Appendices A, C, and E. We discuss the Meraux air 

monitor in the next response. 

Comment: The commenter states that air monitoring data for the years 2008-2012 at the 

Meraux air monitor demonstrate that recent plant modifications at the Valero Energy 

Meraux refinery have resulted in increased SO2 concentrations. The commenter notes that 

the 2012 highest annual 1-hour SO2 concentration of 59 ppb at the Meraux air monitor, as 

well as four consecutive 5-minute readings above 75 ppb, took place around the same 

time as the Valero Energy Meraux refinery reported flaring. The commenter notes that 
Page 36 of 63

there is a public health concern at the elementary school where the Meraux air monitor is 

located, as school children were exposed to these high SO2 levels and studies have linked 

short-term exposure to adverse respiratory effects, especially when children are 

exercising or playing. The commenter contends that air monitoring data from the Meraux 

and Valero air monitors demonstrate that the Valero Energy Meraux refinery is the major 

contributor to violations of the 1-hour SO2 NAAQS at both the Valero and Meraux air 

monitors as well as at the elementary school, that there is a need to implement long-term 

solutions, and that the Valero air monitor could potentially in the future demonstrate 

nonattainment if there are no further emissions reductions at the Valero Energy Meraux 

refinery. 

EPA’s Response: As stated in a previous response, EPA is basing its decision to 

designate St. Bernard Parish nonattainment on the three most recent years of certified 

data from regulatory air monitors in the area. As discussed in our Technical Support 

Document, we considered 2009-2011 data from the three regulatory monitors in the area: 

the Chalmette Vista, Chalmette High School, and Meraux monitors. Although we 

acknowledge the commenter’s concerns regarding exceedances of the 1-hour SO2

standard at the Meraux air monitor, out of the three monitors only the Chalmette Vista 

monitor is violating the 1-hour SO2 standard based on 2009-2011 air monitoring data. 

The TSD explains in further detail what sources appear to be contributing to violations at 

the Chalmette Vista monitor. As stated in a previous response, as part of the SIP 

development process, LDEQ must determine which sources in the area must install what 

controls to attain the standard as expeditiously as practicable, but no later than the 

statutory attainment date. EPA anticipates working with LDEQ in this process. 

With respect to the Valero air monitor, although we believe the data from the Valero 

monitor is informational in many respects, the data does not meet the requirements in 40 

CFR Part 58 Appendices A, C, and E. Because ambient air quality data used by the EPA 

for establishing violations of the NAAQS must meet the requirements in 40 CFR Part 58 

Appendices A, C, and E, EPA cannot consider data from the Valero monitor for purposes 

of establishing NAAQS violations for designation purposes.

Comment: The commenter states that high SO2 levels were also monitored at LDEQ’s 

former air monitoring sites, and provides information on the highest annual 1-hour SO2

concentrations and 99th percentile data from specific years for these air monitors: the 

Mehle site (located in Arabi); the Algiers “Entergy” site (located in Orleans); the 

Chalmette High site (located in St. Bernard’s only high school). The commenter states 

that high monitored SO2 concentrations at the former Chalmette High site demonstrates 

that student health should be protected, while high monitored SO2 concentrations at the 

former Algiers Entergy air monitor in Orleans Parish demonstrates the need for deploying 

monitors on the west bank of the Mississippi River. 

EPA’s Response: As explained in a previous response, current Federal air monitoring 

requirements do not require that an SO2 monitor be located on the west bank of the 

Mississippi River in Orleans Parish. 
Page 37 of 63

However, we note that the EPA is separately evaluating implementation of the SO2

standard, including evaluation of air monitoring requirements. Opportunities for 

additional public input will be available as necessary changes to existing rules, if any, and 

guidance are developed. Additional information on EPA’s SO2 implementation plans can 

be found at the following websites: Sulfur Dioxide Implementation - Programs and 

Requirements for Reducing Sulfur Dioxide 

http://www.epa.gov/oaqps001/sulfurdioxide/implement.html and at Next Steps for Area 

Designations and Implementation of the Sulfur Dioxide National Ambient Air Quality 

Standard 

http://www.epa.gov/oaqps001/sulfurdioxide/pdfs/20130207SO2StrategyPaper.pdf. 

Furthermore, EPA conducts a comprehensive annual review to ensure that the state has a 

monitoring network in place that meets the technical requirements of 40 CFR Part 58 and 

its appendices. The public will be able find the public notice for LDEQ’s Ambient Air 

Monitoring Network Plan by June 1, 2013, at 

http://www.deq.louisiana.gov/apps/pubNotice/default.asp. Part 58 provides at a minimum 

a 30-day public inspection opportunity for every annual monitoring network plan 

presented by the States and local agencies that develop the plans; moreover, whenever a 

plan proposes network modifications, a public comment opportunity is furnished by 

either the State or EPA. We invite future public participation from this commenter and 

others when these opportunities are provided. 

Comment: The commenter argues that Louisiana law prohibits LDEQ from issuing a 

permit that maintains a nuisance or a danger to public health and safety, and notes that air 

quality in St. Bernard is very poor sometimes. The commenter states that as the public 

trustee under the State Constitution, LDEQ has a duty to require state-of-the-art 

technology and additional monitoring to ensure that the air permit limits of the three 

major sources in the area are maintained. 

EPA’s Response: We acknowledge the commenter’s concerns related to high monitored 

SO2 concentrations in St. Bernard Parish, however, we note that LDEQ’s duties under 

state statute are outside the scope of the designations process. A nonattainment 

designation triggers a federal requirement for LDEQ to develop a SIP that must adopt the 

necessary controls for the area to attain the standard as expeditiously as practicable, but 

no later than the statutory attainment date. We anticipate the SIP will result in improved 

air quality and will safeguard public health in St. Bernard Parish. 

Comment: Two commenters state they are residents of St. Bernard Parish and express 

support for a nonattainment designation for the Parish. One commenter states that 

residences in the area are constantly exposed to SO2 and H2S emissions, with the 

resulting odors often forcing residents to shelter indoors and making outside ventilation 

not an option. The commenter states that pollutant emissions have caused damage both to 

people’s health and to residences in the area. The commenter believes it is time for 

industry to address this issue. 

EPA’s Response: We acknowledge the commenters’ support for a nonattainment 

designation for St. Bernard Parish. We also acknowledge the commenter’s concern with 
Page 38 of 63

the impact high SO2 concentrations have on the communities in the area. LDEQ is 

responsible for developing a SIP that includes controls for sources in the area and 

contains an attainment demonstration showing St. Bernard Parish will attain the standard 

by the statutory attainment date. 

Comment: The commenter believes that when EPA mandates gasoline sulfur reduction, 

this may result in lower tailpipe emissions but it also results in high levels of sulfur 

emissions at centralized locations surrounding the refineries. The commenter argues that 

this places the burden on the communities surrounding the refineries. The commenter 

believes that before mandating gasoline sulfur reduction, EPA should require the latest 

pollution control technology that will provide the intended goal of sulfur emissions 

reductions. 

EPA’s Response: As stated in a previous response, issues related to the potential impact 

of source compliance with new federal air pollution regulations are outside the scope of 

the designations process. If compliance with the EPA gasoline sulfur reduction 

requirements results in higher levels of sulfur emissions at refineries in St. Bernard 

Parish, in the development of the nonattainment SIP the LDEQ must take these increases 

into consideration and ensure that the control measures in the SIP will put the Parish into 

attainment by the deadline. However, we note that before promulgating a new federal air 

pollution regulation, EPA develops technical, economic, and environmental analyses that 

are available for review and comment during the public notice and comment period of at 

least 30 days after a new federal regulation is proposed.

Comment: While the commenter agrees with the designation of St. Bernard Parish as 

nonattainment, the commenter disagrees with how EPA referred to that area as the “New 

Orleans Area.” The commenter states that labeling the “New Orleans Area” as 

nonattainment without the inclusion of a specific political boundary or definition will 

cause confusion. The commenter asks EPA to either remove its label of St. Bernard 

Parish as the “New Orleans Area,” or change the label to “New Orleans Metropolitan 

Statistical Area.” 

EPA’s Response: EPA apologizes for any confusion, our reference to the “New Orleans 

Area” may have made with respect to designations, and we are clarifying that we are 

initially designating only St. Bernard Parish nonattainment. References to the “New 

Orleans Area” have been corrected accordingly. 

3.2.6.2 General Comments on Texas

Comment: The commenter reinforces the 2012 recommendation for an attainment 

designation for ten counties and an unclassifiable designation for all remaining counties 

in Texas. The commenter believes that EPA should designate areas in Texas in 

accordance with Governor Rick Perry’s 2012 recommendations. In support of this 

position, the commenter provides 2009-2011 design values and preliminary 2010-2012 

design values for these ten counties, stating that the data demonstrate the design values 

continue to trend downward. The commenter also expresses appreciation for EPA’s 
Page 39 of 63

willingness to work with states regarding implementation of the 1-hour SO2 NAAQS and 

for the flexibility being provided on the implementation schedule for this NAAQS. 

EPA’s Response: EPA acknowledges the support the commenter expresses regarding 

our approach to developing an implementation strategy for the 1-hour SO2 NAAQS. In 

proposing designations and making final designation decisions, EPA has taken into 

consideration the designation recommendations provided by the commenter. However, 

EPA is proceeding at this time with initially designating as nonattainment most areas in 

locations where existing monitoring data from 2009-2011 indicate violations of the 1-

hour SO2 standard. We are not yet prepared to issue final designations for other types of 

areas, and will designate them in future final designations actions. This includes areas in 

Texas and areas in other states where monitored air quality data from 2009-2011 does not 

show violations of the 1-hour SO2 standard. The EPA expects to be able to proceed with 

designation actions in these areas once additional data are gathered. Additional 

information on EPA’s still developing SO2 implementation strategy can be found at the 

following websites: Sulfur Dioxide Implementation - Programs and Requirements for 

Reducing Sulfur Dioxide http://www.epa.gov/oaqps001/sulfurdioxide/implement.html

and at Next Steps for Area Designations and Implementation of the Sulfur Dioxide 

National Ambient Air Quality Standard 

http://www.epa.gov/oaqps001/sulfurdioxide/pdfs/20130207SO2StrategyPaper.pdf.

3.2.7. EPA Region 7

3.2.7.1. Muscatine County Area

Comment: One commenter supports EPA’s proposed designation of Muscatine County, 

Iowa as nonattainment for sulfur dioxide (SO2), as described in the EPA Responses to

State and Tribal 2010 SO2 Designation Recommendations.

The commenter supports the designation of the entire county as nonattainment, rather 

than some subset of the county. In addition, the Council supports a consideration of a 

portion of Louisa County as nonattainment because an area of Louisa County is likely 

contributing to the violation of air quality standards in Muscatine County. The 

MidAmerican Louisa coal plant is located just south of Muscatine County in Louisa 

County. According to Iowa DNR, this coal plant emitted 7,075 tons of sulfur dioxide in 

2010. It is likely necessary for EPA to designate as nonattainment the portion of Louisa 

County that includes this large source of sulfur dioxide emissions in the final 

nonattainment designation in order to ensure the NAAQS for Muscatine County is met in 

future years.

The Commenter urges EPA to designate a portion of Louisa County as in nonattainment

for contributing to air quality violations in Muscatine County. There is a small section of 

Louisa County that is adjacent to and just south of Muscatine County that includes a large

source of sulfur dioxide emissions. The source is MidAmerican Energy’s Louisa

Generating Station, located less than 2 miles from the Muscatine County boundary. In 

fact, a portion of the contiguous property associated with this coal plant, which stores dry 

coal ash, appears to be in Muscatine County. The Louisa Generating Station is a major
Page 40 of 63

emitter of SO2emissions and contributes to Muscatine County’s violation of the 2010 SO2

NAAQS. Accordingly, the commenter recommends that the recommended nonattainment

area boundary of Muscatine County be expanded as to include the portion of Louisa

County with the Louisa Generating Station. The commenter indicates that while the

Louisa Plant is primarily located outside Muscatine County, it still contributes to the poor 

air quality in Muscatine County. EPA’s guidance on designations indicates that states

should provide information showing that “violations are not occurring in nearby portions

that are excluded from the recommended nonattainment area” and that “excluded portions

do not contain emission sources that contribute to the monitored or modeled violation.”

Since the Louisa Generating Station is a major source of SO2emissions that contributes

to Muscatine County’s nonattainment, it would be inappropriate not to include it in a

nonattainment designation.

EPA’s Response: The EPA’s proposal to include all of Muscatine County as the 

presumptive nonattainment area boundary was based on the EPA’s determination that the 

Musser Park monitor was reporting nonattainment with the NAAQS. Following the 

EPA’s proposal, IDNR performed a technical analysis supporting a revised 

nonattainment boundary and provided EPA this analysis as a comment to our proposal. 

EPA’s proposed default nonattainment boundary did not include the Louisa Generating 

Station (LGS) in neighboring Louisa County; however IDNR’s analysis included an 

evaluation of the LGS facility for its contribution at the violating monitor. The LGS 

facility is located south of the violating monitor, which is the general direction of the 

sources implicated by IDNR’s wind rose analysis as causing or contributing to the 

violations detected at the Musser Park monitor. However, since EPA’s February 2013 

letter (our “120-day letter”) to Iowa indicating that EPA planned to modify Iowa’s 2011 

recommendation did not address this source, we are not yet prepared to conclude in this 

final designation action that the emissions from the LGS facility contribute to the 

monitored violation or to other possible violations, and we will make final designations 

decisions for areas outside Muscatine County in a subsequent round of final designations. 

CAA section 107(d)(1)(B)(ii) requires that before issuing a final designation that includes 

a modification to a state’s recommendation, EPA must give the state at least 120 days 

notice of such a modification. As we have not yet provided such notice to Iowa 

regarding the LGS facility, we cannot yet include the LGS source in this final designation 

action. In addition, the EPA is not yet reaching a conclusion concerning areas and 

sources that are not included in the initial Muscatine area nonattainment boundary, and 

will address final designations for these areas and their sources in the future.

Comment: If EPA chooses not to include the area of Louisa County that encompasses the

Louisa Generating Station in its nonattainment designation, EPA must at the minimum

require the state to include controls for the Louisa Generating Station in the State

Implementation Plan (SIP). The Clean Air Act requires that nonattainment plan provisions

must “provide for the implementation of all reasonably available control measures as

expeditiously as practicable (including such reductions in emissions from existing sources

in the area as may be obtained through the adoption, at a minimum, of reasonably

available control technology) and shall provide for attainment of the national primary

ambient air quality standards.” The Louisa Generating Station should qualify as one of 
Page 41 of 63

the “existing sources in the area” even though it is not directly in the designated 

nonattainment area. The previously cited section of the Clean Air Act refers to the general

area that could affect air quality in the designated nonattainment area. If SIPs were only

required to place controls solely on sources within the designated nonattainment area, the

Clean Air Act would not specifically refer to “nonattainment area” later in the same

section.

EPA’s Response: The CAA allows states the discretion to implement specific control 

strategies that demonstrate attainment of the NAAQS in each nonattainment area. The 

EPA will review Iowa’s future State Implementation Plan (SIP), submitted in response to 

the EPA’s 2010 SO2 Primary NAAQS initial boundary designation, and determine 

whether the SIP adequately demonstrates that the nonattainment area will attain the 

NAAQS in an expeditious manner, in accordance with Sections 110, 172 and 192 of the 

Clean Air Act and relevant guidance. The issue of the adequacy of the SIP for the initial 

Muscatine nonattainment area is not yet ripe, as the SIP has not yet been developed by 

Iowa or submitted to EPA for review for approval. The EPA also notes that areas not 

currently included in the initial Muscatine nonattainment area will be addressed in a 

subsequent round of designations, and Iowa will be responsible for the development of 

control strategies for those areas as necessary in future State Implementation Plans.

Comment: Commenters are “supportive of effective regulatory action, based on sound 

public health and scientific research aimed to clean our air...While the SO2 readings are 

highest in neighborhoods surrounding the worst offenders of our air quality laws, air is 

not stagnant and moves to cover all citizens who reside in our county...Clean Air 

Muscatine (CLAM) therefore supports such designation and, and sees no viable 

alternative to a county-wide designation.”

EPA’s Response: The EPA acknowledges the concerns of this commenter, but finds that 

the technical analysis performed by the IDNR that included an analysis of monitoring 

data, meteorological data, wind roses, proximity of sources to the violating monitor and 

the sources’ magnitude of emissions supports a smaller initial nonattainment area 

boundary. This boundary includes the Muscatine County sources that EPA has sufficient 

information to conclude are impacting the Musser Park monitor. EPA is not yet reaching 

a conclusion concerning areas and sources not included in the initial nonattainment 

boundary, and will address these areas in a future final designations action.

Comment: Nonattainment boundary needs to include the area of Muscatine County that 

Mid American Corporation has proposed for the construction of a new nuclear power 

plant or natural gas power plant.

EPA’s Response: The EPA bases its nonattainment boundary designations upon sources 

contributing to a violation of the NAAQS and not upon future sources of emissions. 

Additionally, following receipt of this comment, the Mid American Corporation 

voluntarily withdrew its permit request for a new Muscatine County, Iowa nuclear or 

natural gas power plant. Therefore, the comment is moot, and it is not necessary for EPA 

to further respond to it.
Page 42 of 63

3.2.8. EPA Region 8

3.2.8.1. General Comments

Comment: One commenter says EPA should move forward with the revocation of the 

older SO2 standards (annual and 24-hour). However, since the revocation has been tied 

to the designation process, which has been pushed out to 2020, it appears that states are 

asked to implement three separate SO2 NAAQS for the next eight years. This causes a 

burden for collecting and processing monitoring data, determining compliance, and 

conducting modeling and permit analysis for three separate standards.

EPA’s Response: The 2010 SO2 NAAQS rulemaking established how EPA would move 

forward with the revocation of the prior annual and 24-hour standards after designating 

areas for the new 2010 1-hour SO2 NAAQS. EPA’s rules provide that for most areas the 

24-hour and annual standards will remain in effect in each area for one year following the 

effective date of its initial area designation under section 107(d)(1) for the new 1-hour 

SO2 NAAQS. (See 75 FR 35520; June 22, 2010.) However, for areas that were 

designated nonattainment under the prior NAAQS at the time of the 2010 NAAQS’ 

promulgation, or that were still subject to a SIP Call under the prior NAAQS, revocation 

of the prior NAAQS will not occur until such areas develop and submit, under CAA 

section 191, and EPA approves, a SIP showing attainment of the 1-hour NAAQS. 40 

CFR 50.4(e). Several Region 8 areas are subject to this regulatory exception, which was 

not challenged in the recent litigation concerning the 2010 SO2 NAAQS, and which no 

one timely petitioned the agency to reconsider. See 75 FR at 35581, n.41. Moreover, it 

is outside the scope of this limited designations action to consider any amendment to the 

NAAQS provisions that established how revocation of the prior NAAQS would occur. 

We certainly did not, in our proposed designations, indicate any intent to reopen section 

50.4(e) or to reconsider the final decisions reached on this issue in the 2010 NAAQS 

rulemaking. However, regardless of when and whether revocation of the prior NAAQS 

occurs, we note that in the preamble to the final 2010 NAAQS we explained that any 

existing SIP provisions under CAA sections 110, 191, and 192 associated with the annual 

and 24-hour SO2 NAAQS will remain in effect, including all currently implemented 

planning and emissions control obligations, including both those in the State’s SIP and 

those that have been promulgated by EPA in FIPs. This will ensure that both the new 

nonattainment NSR requirements and the general conformity requirements for a revised 

standard are in place so that there will be no gap in the public health protections provided 

by these two programs. It will also ensure that all nonattainment areas under the annual 

and/or 24-hour NAAQS and all areas for which SIP calls have been issued will continue 

to be protected by currently required control measures. See 75 FR at 35580-82.

As mentioned above, EPA’s rules provide that the annual and 24-hour NAAQS remain in 

place for any areas that were designated nonattainment under those NAAQS when the 

2010 NAAQS was promulgated, or any area for which a State has not fulfilled the 

requirements of a SIP call, until the affected area submits, and EPA approves, a SIP with 

an attainment, implementation, maintenance and enforcement SIP which fully addresses 
Page 43 of 63

the attainment and maintenance requirements of the new SO2 NAAQS. This, we 

explained in the final 2010 SO2 NAAQS preamble, in combination with the CAA 

mechanisms provided in section 110(l), 193, and 172(e) will help to ensure that continued 

progress is made toward timely attainment of the SO2 NAAQS. No one timely 

challenged EPA’s conclusions regarding this approach, and we are not revisiting them in 

this initial designations action.

Comment: One commenter discusses that in the past, EPA has indicated it would seek to 

use dispersion modeling to make attainment designations for the 1-hour SO2 NAAQS.

(see EPA's proposed "Guidance for 1-Hour SO2 NAAQS SIP Submissions.") The 

commenter continues that dispersion modeling of emissions can greatly over predict the 

pollutant concentrations. Several commenters state that dispersion modeling is a tool that 

would be best used for planning decisions and not for area designations.

EPA’s Response: In this final designations action regarding areas with monitored 

violations of the 2010 SO2 NAAQS, we are not reaching any conclusions about how to 

use dispersion modeling as a tool for either designations or planning decisions. However, 

we do not agree that it is appropriate to now conclude that modeling is not a tool to be 

used for area designations. In addition to using any valid data generated by existing 

monitors, refined dispersion modeling may appropriately inform specific designation and 

implementation decisions regarding sources that may have the potential to cause or 

contribute to a NAAQS violation. Our historical approach to SO2 designations and 

implementation through permits and emission limitations has involved a combination of 

both monitoring and modeling. If commenters have objections regarding any future use 

of dispersion modeling in a future proposed designations action, they should raise those 

concerns at that time. Such issues are outside the scope of this final designations action.

3.2.8.2. Yellowstone County Area (Billings, MT)

Comment: Multiple commenters support a designation of ‘unclassifiable’ for the Crow 

Reservation.

EPA’s Response: The Crow Tribe of Montana’s Reservation is located adjacent to the 

Yellowstone County (partial) nonattainment area (Billings, MT area) that we are initially 

designating as nonattainment. As discussed in the Billings, MT TSD, this area of Indian 

country does not contain SO2 emissions sources that we are currently prepared, based on 

monitoring data, to conclude are contributing to the design value at the violating monitor 

in Billings. Therefore, EPA is not including the Crow Tribe of Montana’s areas of Indian 

country in the initial Billings, MT nonattainment area. The EPA is not designating any 

areas as unclassifiable in the current round of designations. EPA will designate these 

areas in a future round of final designations.

Comment: Multiple commenters discuss that a ‘nonattainment’ designation would have 

serious current and future economic impacts on businesses and the community in 

Yellowstone County. 
Page 44 of 63

EPA’s Response: The EPA must designate the violating area as nonattainment based on 

CAA section 107(d). The EPA is revising its proposed nonattainment boundary from the 

entire county of Yellowstone to a smaller area in Billings. This information can be found 

in Region 8’s technical support document (TSD) that is included in the docket for this 

action. With respect to impacts on the local economy and businesses, such issues are not 

relevant for designations actions, but the State has flexibility under the CAA to consider 

such impacts as it develops the control strategy to bring the area into attainment of the air 

quality standard.

Comment: One commenter discusses the uncertainty and accuracy/precision issue of 

monitoring ambient data for the new 1-hour SO2 standard. They conclude that it is not 

definitive, confident, or even certain if the standard was exceeded at the Coburn Monitor. 

Another comment is that the EPA has not been able to articulate its own quality 

assurance guidance for adequate accuracy, precision, and reliability for the new 1-hour 

standard. Additionally, the EPA has not specified the criteria necessary for an attainment 

demonstration and is planning to defer this matter. Since this has not been defined it 

would appear unnecessary and premature to rush a nonattainment designation for 

Yellowstone County. Thus the law provides a clear and available alternative to 

nonattainment, unclassifiable. Another commenter discusses the failure to observe the 

basic scientific ideals of reproducibility and repeatability when using carefully collected 

“one of a kind” data can have significant unintended consequences. A parallel analyzer 

operating at the same location could readily provide a running plausibility check on the 

measurements and it would be under identical conditions, as to acknowledge causes of 

error. Replication is not infeasible temporally or spatially. 

EPA’s Response: The EPA has quality assurance regulations that can be found in 40 

CFR part 58 Appendices A – G. Additional information and references can also be found 

in the document titled “Quality Assurance Handbook for Pollution Measurement 

Systems, Volume II, Ambient Air Quality Monitoring Program.” Montana DEQ has an 

approved Quality Management Program and EPA routinely conducts Technical Systems 

Audits of Montana’s monitoring program. The State has provided all the necessary 

information to show that the data that has been reported, including the data it decided to 

invalidate, follows the guidelines specified above. 

Comment: One commenter discusses an additional concern regarding Coburn Road data 

for a nonattainment designation regarding the lack of a reliable method to detect and 

address cases of transient monitor malfunction or the influence of other extraneous 

variables. The commenter continues that invalid data arising from short-term 

malfunction (high concentration outliers) can go undetected and appear ‘validated’ in the 

record. The checks in place are specifically designed with the 500 ppb standard in mind; 

values near 75 ppb are not automatically considered extreme values. The previously 

satisfactory range of 1,000 ppb was too high in relation to the 75 ppb standard, since it 

would be in the lowest 10% of that range. The lower and upper extremes of the range are 

most susceptible to precision errors, and analyzers generally perform most reliably in the 

middle of the range. The commenter discusses that if an analyzer cannot provide an 

appropriate range for the regulatory concentrations then another one should be added. 
Page 45 of 63

MDEQ had several cases of transient problems detected before 2011. The commenter 

discusses an occurrence of a smoke event by the monitor found in Laurel and which 

subsequently showed a spike in SO2. The monitor did not report or flag this data because 

the monitor was not “looking” for this or any other common events but interpreted 

vegetative smoke as significant SO2 relative to the standard. Except for this chance 

report, the data would likely have been recorded and validated as an “unquestioned” or 

“unexplained” high reading. The commenter discusses that this issue is not discussed or 

considered in EPA’s “February 2002 Development of Emissions Inventory Methods for 

Wildland Fire”. 

The commenter provides another ‘unexplained’ transient reading at the Coburn Road 

monitor. This ‘unexplained’ reading occurred after an auto-calibration run. The monitor 

showed an unremarkable reading before the calibration. An hour after the calibration, the 

monitor showed the highest value for the entire 2012 year, but then the following hour 

read close to the value taken one hour before the calibration. The commenter concludes 

that the reading taken 1 hour immediately following the calibration was an outlier, which 

could have been caused by an undetected transient event, but was retained and validated. 

The commenter discusses that including this highest reading results in a 99th percentile 

value for 2012 of 70 ppb. Without the high reading, the 99th percentile value would drop 

to 55 ppb. If 55 ppb were used instead of 70 ppb, the 2010-2012 design value would be 

below 75 ppb. The commenter concludes that the currently accepted systems are not 

equipped to discern these possible false data points. Another commenter concludes that 

data collected prior to August 23, 2010, when monitors were operated and configured to 

evaluate a higher standard, should not be used to determine compliance with the new 1-

hour standard. Calculation of a defensible design value based on 2010-2012 is 

impossible and determination should be done with 2011-2013 data.

EPA’s Response: EPA disagrees with the commenter. Montana DEQ has conducted 

audits at the Coburn Road monitor at levels low enough for the data to be reliable for a 75 

ppb NAAQS compliance determination. The monitor located in Laurel is an industrial 

monitor in the area and not under the management of Montana DEQ. 

The data point that the commenter described in 2012 as an outlier is outside the 

designations years of 2009-2011. However, this data point was reviewed by both the 

State and EPA. It was determined that this exceedance was coincidentally after an hourly 

calibration check and that the exceedance was not caused by the calibration check.

Montana DEQ did lower its audit levels over the three year period, but all audits had 

levels encompassing the 75 ppb level. Because of this, EPA finds that the 2009-2011 

data is robust enough to be reliable for a 75 ppb standard. See Table 1 below for the 

State’s historical audit levels for 2009-2011. Additionally, the comment pertaining to the 

“February 2002 Development of Emissions Inventory Methods for Wildland Fire” is 

outside the scope of this designation action. 

Table 1
Page 46 of 63

Montana DEQ’s Historical Audit Information

Date Audit levels (ppb)

2/25/2009 7.5 82 146 820

5/19/2009 36 147 358 819

8/12/2009 48 153 357 685

11/18/2009 50 186 424 418

3/23/2010 7 73 259 688

6/22/2010 8 74 270 710

9/21/2010 39 181 351 483

12/1/2010 58 228 338 449

3/24/2011 15.5 36.8 90.6 149.7

5/25/2011 29 72.4 126.7 250.5

11/17/2011 41.5 70.1 103.7 206.7

Comment: One commenter discusses that the CAA does not contemplate classifying 

areas nonattainment on a countywide or statewide basis, only for areas which are known 

to be presently “not meeting the standard,” not areas demonstrating compliance. The 

EPA’s ‘default’ county boundary approach is only in the 2011 guidance memo that was 

never subject to external review, where many entities would have expressed significant 

concerns. The commenter continues that Yellowstone County is very large and 

comparable in size to two eastern states, which contain multiple counties. The EPA 

would not designate one of these small states nonattainment if only one monitor showed a 

violation when others showed attainment. Additionally, the EPA should show equal 

consideration to the rest of Yellowstone County as they show to the Crow Reservation, 

where there are no contributing SO2 sources and no ambient monitoring data. The 

boundary should be grounded in reality, thus smaller than the entire county, and based on 

available information, such as prevailing winds, similar local terrain, etc.

EPA’s Response: EPA disagrees that the CAA does not provide for EPA to propose a 

countywide nonattainment boundary, but the commenter’s objection has been rendered 

moot by the final designation covering a smaller area of Yellowstone County. As a 

proposal, the EPA was requesting additional information from the State/local/tribal air 

agencies, stakeholders, and the public on what a nonattainment area boundary should be 

in Yellowstone County. On April 3, 2013, the State of Montana provided additional 

information, which included a five-factor analysis, on the entire county proposal in 

response to EPA’s preliminary decision. Based on an analysis of the data provided by the 

State and commenters, in conjunction with the five-factor analysis, EPA determined that 

a partial county initial designation was appropriate instead of the entire county. EPA 

made the final designations for the 2010 1-hour SO2 NAAQS using an evaluation of the 

recommended five-factors described in designations guidance that was issued by EPA 

through a March 24, 2011, memorandum from Stephen D. Page, Director, U.S. EPA, 

Office of Air Quality Planning and Standards, to Air Division Directors, U.S. EPA 

Regions I-X (Designations Guidance), as well as other relevant information in 
Page 47 of 63

determining an appropriate initial nonattainment area boundary for Yellowstone County. 

Please refer to Region 8’s TSD.

Comment: One commenter discusses that the March 2011 Designations Guidance memo 

only gave states and tribes two months to complete a complex analysis. The designation 

strategy did not give state or local regulators, or affected industry, the chance to address 

the issues proactively. Even given this short time period, MDEQ prepared a compelling 

TSD. However, EPA did not adequately consider MDEQ’s analysis or statutory context 

of a nonattainment area when proposing the entire Yellowstone County (excluding the 

Crow Reservation) nonattainment. The commenter concludes that this is a direct 

contradiction of the intent of the March 2011 memo and intended statutory approach to 

designations where EPA and a state arrive at dissimilar conclusions. Additionally, the 

commenter discusses that the memo omits mention of area-specific analyses conducted 

by other entities that would be impacted by a nonattainment designation, although statute 

allows input from others to a certain extent.

EPA’s Response: The March 2011 Designations Guidance memo identifies that CAA 

section 107(d) provides EPA the authority to make modifications that it deems necessary 

to the recommended designations of areas submitted by states. The designations process 

is primarily between EPA and the state, which is discussed in the CAA section 107(d). 

CAA section 107(d)(2)(B) further discusses publication of designations where 

“Promulgation or announcement of a designation under paragraph (1), (4) or (5) shall not 

be subject to the provisions of sections 553 through 557 of Title 5 (related to notice and 

comment), except nothing herein shall be construed as precluding such public notice and 

comment whenever possible.” Therefore, EPA can provide a public comment period for 

interested parties but is not required to do so. The EPA encourages impacted 

stakeholders to work with their state officials to coordinate an appropriate 

recommendation or response to any EPA proposed boundary modifications during the 

designations process.

Comment: Commenters discuss current and historical data, which are showing 

compliance with the new 1-hour standard and cannot be part of a nonattainment area. 

Five of the six monitors in the Billings/Laurel area show compliance and they are located 

within close proximity to major SO2 sources. The Coburn Road monitor was in 

compliance in 2007-2009, but only indicated a violation in 2010. Evaluation of other 

monitoring sites that were in operation since 2000-2006, but are no longer in service, 

were all disconnected due to low SO2 concentrations. All these sites had 99th percentile 

values and 3-year averages below the standard. The commenter points out that the 

emissions were about 75% higher during 2000-2006. The commenter further discusses 

monitoring conducted in the early to mid-1990s. The sites that were operating in the ‘90s 

had large emissions, but, when normalized for current emission levels, the 99th percentile 

values for these sites were below the new 1-hour standard. These old monitoring areas, 

west and southwest of PPL, should be an attainment area.

EPA’s Response: The EPA agrees that the initial nonattainment area should be revised 

to be smaller than a countywide boundary. However, historical data can only be used for 
Page 48 of 63

informational purposes and non-regulatory monitors cannot be used for purposes of 

establishing a NAAQS violation for designations. The June 22, 2010 final NAAQS rule 

(75 FR 35520) discusses that the standard should use a “concentration-based form 

averaged over three years in order to give due weight to years when 1-hour SO2

concentrations are well above the level of the standard, than to years when 1-hour SO2

concentrations are just above the level of the standard.” Thus the three-year average 

provides more stability for fluctuations when certain years are high compared to a noexceedance based form. The data years that EPA is using for this first initial round of SO2

designations are 2009-2011.

Comment: One commenter discusses that the State of Montana and industry have taken 

a proactive approach to SO2 issues in Yellowstone County and now it appears they are 

being punished with immediate, retroactive nonattainment designation for diligently 

monitoring SO2 concentrations in the area. Montana was not specifically required to 

operate any SO2 monitors in Yellowstone County during the 2009-2010 period and the 

data was never collected to demonstrate compliance with the new standard. However, 

the EPA is proposing to extend the statutory designation years into the future for other 

areas that did not monitor, allowing those areas to address potential problems in the 

meantime and avoid a nonattainment designation.

EPA’s Response: The CAA requires EPA to complete area designations within two 

years after promulgation of a new or revised NAAQS, with a possible one year extension. 

Further, the form of the 2010 1-hour NAAQS is a three year average. Therefore, 

designation decisions based on the most recent three years of SO2 monitoring data 

necessitate using data collected prior to the standard being finalized in June 2010. Based 

on valid SO2 monitoring data from 2009-2011a nonattainment area designation is 

warranted for part of Billings, Montana pertaining to the Coburn Road monitor. The 

Coburn Road monitor is appropriate to be used for this designations process because it is 

an approved regulatory monitor by both the State and EPA. The State is under an 

approved Quality Management Program, where EPA routinely conducts a Technical 

System Audit for Montana’s monitoring program, and the State has provided all 

necessary information to show that the data and the monitor follow all guidelines set out 

by the EPA. The EPA expects to be able to proceed with designation actions in these 

areas without violating monitors once additional data are gathered. Additional 

information on EPA’s still developing SO2 implementation strategy can be found at the 

following websites: Sulfur Dioxide Implementation - Programs and Requirements for 

Reducing Sulfur Dioxide http://www.epa.gov/oaqps001/sulfurdioxide/implement.html

and at Next Steps for Area Designations and Implementation of the Sulfur Dioxide 

National Ambient Air Quality Standard 

http://www.epa.gov/oaqps001/sulfurdioxide/pdfs/20130207SO2StrategyPaper.pdf.

Comment: One commenter discusses that since the standard did not become effective 

until August 23, 2010, all of 2009 and the majority of 2010 data are non-representative as 

these were collected before the new 1-hour standard went into effect. Thus it does not 

meet EPA’s own regulations to use monitoring data for designations only if it meets strict 

technical and quality standards. Because the standard was not in place until after August 
Page 49 of 63

23, 2010, three of the four quarters (and thus 2010) are incomplete by definition in 40 

CFR Part 50, Appendix T. The first three quarters were designed and operated for the 

regulatory purpose of measuring an older, substantially higher NAAQS of 500 ppb and 

thus use of the data is inappropriate for designations with the new 75 ppb standard. 

There is insufficient data to consider 2010 a valid year for determining the design value. 

Also, by denying data collected in 2013, the EPA is effectively and unnecessarily giving 

more weight to this non-representative data. The EPA even acknowledged that the 

monitoring network in the country overall was inadequate to address the new standard 

since the network had been shrinking for many years. The commenter concludes that in 

the majority of the 2009-2011 period, the standard did not exist and that this clearly 

defeats ordinary due process protections. Additionally, the commenter discusses this 

‘look-back’ practice as termed “ex post facto” application of law and the lack of effective 

notice is a selective and arbitrary denial of effective due process. The commenter quotes 

“It is a commonplace of administrative law that ‘[a]n agency may not promulgate 

retroactive rules absent express congressional authority.’” (Nat’l Petrochemical & 

Refiners Ass’n v. EPA, 643 F.3d 958 (DC Cir. 2011)(quoting Nat’l Min. Ass’n v. Dep’t 

of Labor, 292 F.3d 849, 859 (DC Cir. 2002))). The language of the NAAQS statute does 

not provide for retroactive application. Instead, the statute provides additional time if 

needed to make determinations and allows an unclassifiable designation when 

insufficient data are available. Thus EPA’s nonattainment designation determines 

compliance with a new rule based on past behavior that was not subject to the rule for 

which compliance is being measured. The commenter concludes that EPA cannot apply 

the SO2 rule retroactively to emissions that complied with the previous standard and must 

instead use data gathered when the new rule is in effect to determine compliance.

EPA’s Response: EPA disagrees with this commenter. There were no specific changes 

made in the Quality Assurance requirements for SO2 monitoring in 40 CFR Part 58 

Appendix A for the new 1-hour SO2 NAAQS. Thus data collected prior to June 2010 

when the new 1-hour SO2 NAAQS was finalized meet the same SO2 Quality Assurance 

requirements as SO2 data collected after the 1-hour NAAQS was finalized. Montana 

DEQ conducted audits at the Coburn Road monitor at levels low enough for the data to 

be reliable for a 75 ppb NAAQS determination. See Table 1 above for the State’s 

historical audit levels for 2009-2011.

The 75 ppb design level falls within the range of audit values Montana DEQ used, and 

therefore, EPA finds the 2009-2011 data robust enough to be reliable for a 75 ppb 

standard.

EPA also disagrees with the commenter’s suggestion that using valid data that predates 

the new NAAQS for purposes of subsequent designations under the NAAQS somehow 

renders the NAAQS retroactive in its effect. Designations by their very nature have only 

prospective effect under a new NAAQS, and those are limited to triggering a state’s duty 

to develop a prospective attainment plan that may (or may not) include new futureapplicable emissions limitations. And those limits will not be established or impose 

binding obligations on air pollution sources before separate state and federal action is 

taken to adopt them. In no reasonable sense can this statutory structure, in 
Page 50 of 63

implementation, be viewed as constituting any retroactively applicable requirement that 

injures any one in any way. Moreover, adopting the commenter’s view on this issue 

would render it impossible for either states or EPA to ever meet their statutory 

obligations under CAA section 107, as those duties impose deadlines on state governors 

and on EPA that fall before any post-NAAQS 3-year period of monitoring could run and 

generate certified and submitted data. Such a reading cannot be reasonable.

Comment: One commenter discusses that the designations for the Uinta Basin in Utah 

are proposed as unclassifiable for the 2008 ozone NAAQS even though monitors were 

showing a violation. EPA found the data from the non-regulatory monitors in the Uinta 

Basin were inadequate to make a nonattainment designation, although they were 

following the strict requirements set out in 40 CFR Part 58. The same is true for the 

Coburn Road monitor since it did not meet the quality assurance requirements to measure 

the lower emissions of the new standard. Additionally, to achieve “regulatory” status, 

monitors should be subject to adequate government oversight, follow an approved quality 

assurance project plan (QAPP), and provide satisfactory, quality-assured data. If the 

monitoring system does not strictly comply with EPA’s regulatory requirements, then the 

data should not be used to determine NAAQS violations. The required checks under a 

QAPP would not have detected outliers from the 75 ppb standard as extreme values. The 

Coburn Road monitor was not designed or operated for the regulatory purpose of 

measuring compliance with the 75 ppb standard. The three-year average 99th percentile 

value for 2009-2011 is 79 ppb, only 4 ppb above the 75 ppb standard. The potential bias 

range for the Coburn Road monitor was -10 ppb to +7 ppb, where 4 ppb is within this 

range. One commenter concludes that since the data is within this bias and error range, it 

is not known whether the area is exceeding the standard. Thus this data is insufficient to 

designate the area nonattainment. Another commenter further discusses that corrective 

action is needed when quality assurance errors are found and the monitor must be 

specifically designed to collect the correct data for the specific NAAQS if the data is to 

be used for nonattainment designations. The commenter concludes that since the data 

from 2008-2010 do not meet EPA’s high quality standards and were gathered before the 

effective date of the new NAAQS, EPA must designate Yellowstone County as 

unclassifiable.

EPA’s Response: The specific circumstances leading to the EPA’s conclusions that data 

from the Uinta Basin monitors were non-regulatory were unique to those monitors, and 

included the lack of approval of a monitoring QAPP by the EPA and a lack of complete 

quality assured data showing an ozone NAAQS violation. The Uinta Basin ozone 

monitors referred to in this comment did not have an approved Quality Assurance 

oversight program at the time of designations for the 2008 ozone standard. In addition, 

ozone monitors in the Uinta Basin did not have three years of data available at the time of 

designations. The monitor at Coburn Road is operated under a Quality Management Plan 

by the State of Montana, and has generated three calendar years of data. Montana’s 

historical audit levels are discussed in a separate response and summarized in Table 1 

above. 
Page 51 of 63

Comment: One commenter discusses that SO2 monitors in the Billings/Laurel area, 

including the Coburn Road monitor, have shown compliance with the previous 500 ppb 

standard since 2001.

EPA’s Response: The comment is outside the scope of this designation action. We are 

not reaching conclusions with respect to whether the area is meeting the 500 ppb 

standard.

Comment: One commenter discusses that Coburn Road monitor was only marginally in 

violation, is in an atypical location, and it will virtually be in compliance from 2011 

forward. 

EPA’s Response: The EPA disagrees that there was a ‘marginal’ violation of the 1-hour 

SO2 standard. Per the CAA section 107(d)(1)(A)(i) a nonattainment area is any area that 

does not meet the national primary or secondary ambient air quality standard for the 

pollutant or that contributes to a nearby area that does not meet the standard. The design 

value for designations for the period 2009-2011 is 79 ppb, which exceeds the 75 ppb 1-

hour SO2 standard. EPA also disagrees that the Coburn Road monitor is located at an 

atypical location. The monitor was sited to represent the maximum concentration of SO2

for the area, which would better protect public health, and approved by EPA into the 

State’s monitoring network. The 79 ppb design value for the Coburn Road exceeds the 

75 ppb NAAQS for 2009-2011, and the design value for 2010-2012 of 78 ppb also 

exceeds the NAAQS. Therefore the area associated with this monitor is appropriately 

designated nonattainment.

Comment: Multiple commenters request that EPA defer classification of Yellowstone 

County, as EPA intends to do for other areas lacking representative, or any, monitoring 

data. Since these other areas are being given the opportunity to demonstrate or achieve 

compliance in the future, the State of Montana and Yellowstone County should be 

afforded the same opportunity.

EPA’s Response: The EPA disagrees that parts of Yellowstone County should not be 

designated during this initial designations process. For this initial designation rulemaking, 

EPA is designating areas as nonattainment that have monitored violations for the 2009-

2011 design value years. Since the Coburn Road monitor has a design value greater than 

the new 1-hour SO2 standard, in accordance with CAA section 107(d)(1)(A)(i), this area 

should be designated as nonattainment. We are not prepared to reach designations 

conclusions about other areas, which will be addressed in future final designations 

actions.

Comment: One commenter discusses that a ‘nonattainment’ designation ignores the 

balance that should be considered and that such a decision needs to be data-driven and 

defensible. Some commenters discuss that EPA’s proposed designation of nonattainment 

is premature, inappropriate, unnecessary, and should be reconsidered. Another 

commenter discusses that the statute does not suggest that nonattainment was easily 

determined, while attainment could only be defined in the future. This is two sides of the 
Page 52 of 63

same coin. The commenter goes on to discuss that an attainment area would be those 

areas that affirmatively meet the standard and for all other areas, the statute expressly 

contemplates designation of unclassifiable as satisfying all requirements of the initial 

designation, with final attainment or nonattainment designation to be identified at a later 

date, based on additional monitoring data and analysis. The CAA does not require EPA 

to designate nonattainment, nor is there anything that requires EPA to modify state 

recommendations. 

EPA’s Response: The EPA disagrees with the commenters. The CAA section 107(d)(1) 

provides definitions for the terms attainment, nonattainment, and unclassifiable. The 

definition of nonattainment is any area that does not meet the national primary or 

secondary ambient air quality standard for the pollutant or that contributes to a nearby 

area that does not meet the standard. The definition of unclassifiable is any area that 

cannot be classified on the basis of available information as meeting the NAAQS. EPA’s 

review of the available information concludes that there is no lack of information that 

would justify any action, in accordance with CAA section 107, for the area around the 

violating Coburn Road monitor other than a nonattainment designation. Our TSD 

supports this designation. Additionally, CAA section 107(d)(1)(B)(ii) provides the 

Administrator the option to make modifications to the recommendations provided by 

states as deemed necessary.

Comment: One commenter discusses that EPA did not address 2012 emissions or 

monitoring data in their analysis. This year is more representative of current air quality 

and with the lower emissions, reduced compared to 2010 emissions, the area would be 

attaining.

EPA’s Response: The EPA disagrees that it did not review 2012 data during the oneyear extension. However, the 2010-2012 design value was still above the standard at 78 

ppb. Since 2012 data did not provide any new information, the EPA based its 

designation of nonattainment on 2009-2011 design value that is in violation of the 

NAAQS, consistent with the other areas that EPA is designating as nonattainment at this 

time.

Comment: Multiple commenters state that 2011-2013 data would provide the EPA a 

clearer picture of emissions in Yellowstone County. This would show Yellowstone 

County as currently attaining. Another commenter states that 2011-2013 would be the 

first period in which the 2010 standard was actually in effect for the entire period. Years 

2011 and 2012, evaluated individually, do not show an exceedance at the 99th percentile 

level, nor would it suggest a violation. 

EPA’s Response: The EPA agrees that 2011, as an individual year, does not have a 99th

percentile 1-hour value above 75 ppb. However, compliance determinations for the 1-

hour SO2 NAAQS are based on a 3-year average of 99th percentile values, not on a single 

year. The 2011 design value (based on the three years 2009-2011) for the Coburn Road 

monitor in Yellowstone County violates that standard at 79 ppb. For this initial 

designation rulemaking, EPA is designating areas as nonattainment that have a monitored 
Page 53 of 63

violation for the design value for the years 2009-2011. Note also that the 2012 design 

value (based on the three years 2010-2012) also violates the standard at 78 ppb. Since 

the Coburn Road monitor has a design value greater than the new 1-hour SO2 standard, in 

accordance with CAA section 107(d)(1)(A)(i), this area is appropriately designated as 

nonattainment. The State’s Quality Assurance measures, as discussed elsewhere in these 

responses, also support EPA’s finding that the 2009-2011 data are complete, quality 

assured, reliable for a 75 ppb standard, and show a regulatory violation of the new 1-hour 

SO2 NAAQS.

Comment: Multiple commenters question the reliability and representativeness of 2010 

data, and the data set of 2009-2011 used by EPA, at the Coburn Road monitor in 

Yellowstone County for current and future conditions. Another commenter discusses that 

2009, 2011, and 2012, represent similar and consistent operating conditions and reflect 

future operations, which are enforceable, permanent, and quantifiable emission 

reductions. Other comments discuss that since 2010 is the one year that is the basis of 

EPA’s recommendation of nonattainment, it should be reliable and representative. 

Another commenter discusses that the majority of the exceedances for 2009-2011 were in 

2010. From 2008-2012, 70% of highest monitored concentrations were in 2010 and from 

this same period that the average for 2010 was 13 ppb higher than the other four-year 

averages. This same commenter discusses that the standard deviation of 99th percentile 

over the past six years ranges from 63.2 ppb – 88.1 ppb, which represents reasonable 

values and any data outside of this range should be considered outliers. From this 2007, 

2008, and 2010 are questionable. Therefore, the 2010 monitoring data from Coburn 

Road monitor should not be used for the designations process. 

EPA’s Response: The EPA disagrees. While the numbers of exceedances in 2010 are

higher than in other years, neither EPA nor the State has found any reason to believe that 

the values read by the Coburn Road monitor are not valid readings. Quality assurance 

checks done by the State show that the monitor was reading correctly and that the data 

are valid. The potential for inter-annual variability in data is a key reason that NAAQS 

compliance is determined by using a three-year average form of the standard (using 

consecutive years), so it is inappropriate to further account for variability by selecting 

specific years to use or to discard.

Comment: Multiple commenters discuss that SO2 values for 2010 were influenced by 

the requirement under an EPA, State of Montana and ExxonMobil consent decree for 

catalyst testing at ExxonMobil and that the data is not representative of current or future 

concentrations. A commenter also discusses that 2008 is not representative due to early 

catalyst testing at ExxonMobil under the consent decree. Another commenter discusses 

that the consent decree driven emissions increase in 2010 corresponds directly to a 

majority of the documented NAAQS exceedances, 10 of 16, for the 2009-2011 timeperiod.

EPA’s Response: The EPA disagrees that 2008 and 2010 are not representative. Found 

within Region 8’s TSD, catalyst testing performed at ExxonMobil in 2008 and 2010 did 

not correlate with the days of exceedances. The exceedances were primarily from the 
Page 54 of 63

west-southwest wind direction, which would make ExxonMobil upwind of the monitor 

during the exceedances. EPA’s response to this comment can be found in the “Air 

Quality,” “Emissions and Emissions Related Data,” and “Meteorology” sections of 

Region 8’s TSD.

Comment: Multiple commenters support recommendations for an “unclassifiable” 

designation for Yellowstone County until full, reliable data is collected. Another 

commenter asserts that the EPA improperly concluded in their TSD that the 2009-2011 

dataset provides adequate evidence of emissions of current and future years and is not 

indicative of current and future nonattainment of the NAAQS. Thus available data does 

not support this conclusions and the county should be designated unclassifiable. The 

commenter further discusses that the unclassifiable designation was developed in part to 

avoid a needless rush to judgment on a nonattainment or attainment area. Therefore, 

EPA should agree with Montana’s unclassifiable designation and then work with MDEQ 

to ensure that the standard continues to be met. This approach would avoid unwarranted 

costs for unnecessary emission reductions. Another commenter discusses that it would 

be reasonable to presume that the CAA does not expect a state to revise their SIP when 

federal requirements in a consent decree interfere with attainment (42 USC § 

7410(a)(3)(C)).

EPA’s Response: The EPA is not designating any areas of the country as unclassifiable 

with this initial designation rulemaking. Areas that do not have monitored violations will 

be designated in future final actions. However, EPA is designating, as “nonattainment,” 

areas that have a monitored violation for the 2009-2011 design value years. In Region 

8’s TSD, EPA discusses that the consent decree between ExxonMobil, the State of 

Montana, and EPA was not the cause of exceedances in 2010. Since the Coburn Road 

monitor has a design value for 2009-2011 greater than the new 1-hour SO2 standard, in 

accordance with CAA section 107(d)(1)(A)(i), this area is appropriately designated as 

nonattainment. 

Comment: Multiple commenters discuss PPL-Montana’s plan to mothball the Corette 

power plant in April 2015 because of upcoming regulations. It would take a significant 

amount of time to resume operations due to permitting, equipment installation, etc. The 

commenters discuss that in 2010-2012, there were no exceedances of the 1-hour standard 

when PPL was offline or even when winds were from other directions other than from the 

southwest. Therefore, the monitor data will decrease drastically and remain low 

indefinitely as a direct result of PPL’s power plant being mothballed. The commenters 

further discuss that if PPL were to decide to resume operations, they would first need to 

demonstrate compliance with the new Mercury Air Toxics (MATS) rule, and thus 

installation of a baghouse would be necessary. The commenters discuss that the 

baghouse will incidentally reduce SO2 emissions, on top of the capture achieved by the 

current Electrostatic Precipitator (ESP), by capturing particles and ash material, and 

perhaps 10% of SO2 could be captured on this material. They conclude that 10% is very 

significant since PPL accounted for about 90% of emissions to the Coburn Road monitor 

site during 2010. Reductions of SO2 necessary to achieve demonstrated compliance are 

not very large and a small tonnage reduction can be very significant.
Page 55 of 63

EPA’s Response: The EPA agrees that if the Corette power plant were to be mothballed 

that the overall emissions in the area would be reduced. However, PPL does not plan to 

mothball or add controls until April 2015, or April 2016 if the extension is granted for 

compliance with the MATS rule. The State has flexibility under the CAA for a 

nonattainment area to consider impacts, such as these, as it develops the control strategy 

for the SIP to bring the area into attainment of the air quality standard.

Comment: Some commenters discuss working to reduce SO2 at Corette before the 2018 

NAAQS compliance date in order to preclude a nonattainment designation. EPA should 

take into account this potential commitment on the part of PPL and MDEQ with respect 

to the designations decision. Other areas are being granted this deferral under the Next 

Steps policy statement by EPA. Another commenter discusses that, if provided more 

time, the State and PPL would use the time to establish an hourly emission limit for 

certain sources and evaluate where additional reductions need to be made.

EPA’s Response: The EPA agrees that PPL and MDEQ should be working to reduce 

SO2 emissions from the Corette power plant, however, we do not agree with deferring 

designation for this area that has a monitored violation. Other areas for which we are not 

yet prepared to reach final designations decisions are areas for which additional 

monitoring data or other information are needed. Concerns about how those areas, which 

are outside the scope of this final action, are to be treated should be raised in response to 

our future proposed designations for those areas. The Coburn Road monitor is violating 

the 1-hour SO2 standard for 2009-2011 based on valid data and is appropriately 

designated nonattainment with this rulemaking.

Comment: One commenter discusses that the nonattainment area should extend only a 

few thousand feet northeast of Coburn Road monitor, stopping short of the elevation 

contour of lower Coburn monitor, Brickyard monitor, Lockwood Park monitor, Johnson 

Lane monitor, and Pine Hills monitor, where all these monitors and their representative 

areas show attainment. These areas show compliance and demonstrate that Lockwood 

facilities do not contribute to exceedances or violations at Coburn Road monitor. The 

commenter went further to discuss that when Phillips66 or CHS were online but not PPL 

Corette, there were no exceedances. The commenter also noted that there were still 

exceedances when Western Sugar was offline but only when PPL was online. Thus the 

nonattainment area should extend out from contributing source, PPL Corette, not 

significantly farther than Coburn Roads distance from PPL Corette, and exclude all areas 

below the elevation of Lower Coburn station. Another commenter discusses that if EPA 

would designate a portion of the county nonattainment then EPA should be sure to 

include all sources contributing to the nonattainment designation within the boundary. 

The commenter continues that it would be inappropriate to set a designation boundary 

that failed to capture areas that are potentially influenced by the other sources.

EPA’s Response: The EPA agrees that the initial nonattainment area should be revised 

from the entire county to a smaller boundary. The EPA reviewed the State’s five-factor 

analysis and new nonattainment boundary recommendation, which only included the 
Page 56 of 63

violating monitor (Coburn Road monitor) and PPL Corette, and agrees with the State’s 

analysis and revised boundary. The EPA’s detailed response to this comment can be 

found in Region 8’s TSD. We are not at this time prepared to reach final designations 

conclusions regarding any other areas or sources outside the boundary of the initial 

nonattainment area.

Comment: Two commenters submitted a five-factor analysis for a smaller nonattainment 

area boundary for Yellowstone County.

EPA’s Response: The EPA agrees with the commenters on establishing a smaller initial 

nonattainment area boundary. Our detailed response can be found in Region 8’s TSD.

Comment: Some commenters discuss current and future regulations and possible 

impacts on reducing SO2 in the Billings/Laurel area. The commenters included: EPA’s 

refinery initiative and associated consent decrees, existing FIP implementation, 

MATS/utility MACT implementation, regional haze/BART implementation, NSPS 

Subpart Ja, EPA’s flare initiative, and boiler MACT implementation. One commenter 

discusses that all these regulations will have some SO2 reductions at certain facilities in 

the Billings/Laurel area and that the county would demonstrate compliance solely 

through the actions already required by existing and enforceable programs. However, 

another commenter discusses that all but two will have little to no impact on reducing 

SO2 emission, which are the EPA’s refinery initiative/associated consent decree and 

EPA’s FIP. 

The following discusses comments on each of the regulations listed above and EPA’s 

responses.

-EPA’s refinery initiative and associated consent decree, and SO2 FIP 

Implementation: One commenter discusses that between 2002 and 2005, Billings/Laurel 

refineries and representative parent companies each entered into a consent decree with 

EPA and the State of Montana. Phillips66 and CHS have largely completed their consent 

decrees and had emission reductions. ExxonMobil was implementing their consent 

decree, completing catalyst testing, and implementing findings during and after the 2008-

2010 period that EPA describes as “representative of normal emissions.” In 2010, 

ExxonMobil had more than a 1,600 tons per year increase over 2009 and 2011 years, 

which EPA noted as “normal.” Years 2011 and 2012 show dramatic decreases in 

emissions at ExxonMobil. These additional emissions that resulted from the consent 

decree required catalyst testing contributed to the high values in 2010 and since the 

controls have been added, emissions are unlikely to return to 2010 levels. Thus 2010 is 

an anomaly. The commenter also discusses that even though the FIP has been delayed by 

recently completed unsuccessful litigation, it has not rendered the FIP moot and it will 

still apply to those facilities. The FIP primarily applies to flaring events at refineries 

(CHS, ExxonMobil, and Phillips66) and MSCC, where these facilities are required to 

develop and submit to EPA for approval flare monitoring plans. These plans were 

possibly held up by the recent litigation.
Page 57 of 63

EPA’s Response: The EPA has revised the initial nonattainment area to include only the 

Corette power plant and the violating monitor (see Region 8’s TSD). Thus the other 

sources and the areas that will show reductions from the EPA’s refinery initiative and 

from the FIP’s implementation are not addressed in this final action, and will be 

addressed in a future final designations action and are outside the scope of this initial 

nonattainment designation.

-Regional Haze FIP: One commenter discusses that for the Corette power plant 

the Regional Haze FIP revised the SO2 emission standard, which represents a 19% 

reduction in the previously allowable standard. This would effectively eliminate 

previously allowable excursions of high emissions that would cause Corette to exceed the 

standard. Additionally, the FIP would have effectively shaved off about 30% from the 

allowable high-end emissions that Corette would emit. The commenter concludes that to 

ensure the standard is met, Corette would implement fuel blending to address high sulfur 

coal that is shipped to the plant. Another commenter discusses that other than the SO2

limit, which is averaged over a rolling 30-day period, no additional emissions reductions 

would result in the Billings/Laurel area.

EPA’s Response: The EPA agrees that the Regional Haze FIP pertaining to Corette had 

set a lower allowable SO2 limit. However, this lower limit is what the Corette power 

plant is allowed to emit and is based on Corette’s actual emissions with an added margin 

of compliance. Corette’s actual emissions would not necessarily be reduced by the lower 

allowable limit under the Regional Haze FIP. 

-MATS/Utility MACT Implementation. One commenter discusses that the 

facilities affected by this rule would be Corette and YELP. Another commenter discusses 

that for the implementation of this rule, Corette would need substantial controls to lower 

air toxics and SO2 emissions or mothball the plant in April 2015. The options included 

for this rule would be for the facilities to take a hydrochloric acid limit or a SO2 limit and 

it is assumed that Corette would take the hydrochloric acid limit. Any controls installed 

for this rule associated with PM or metal limits will provide co-benefit of additional SO2

control.

EPA’s Response: The EPA has revised the initial nonattainment area to include only the

Corette power plant and the violating monitor (see Region 8’s TSD). Thus the other 

sources and the areas that will show reductions from of the MATS/Utility MACT rule 

(except for PPL Corette) are outside the scope of this initial nonattainment designation

and will be addressed in a future final designations action. EPA agrees that if the Corette 

power plant were to be mothballed, the overall emissions in the area would be reduced. 

However, PPL does not plan to mothball or add controls to Corette until April 2015, or 

April 2016 if an extension under the MATS rule is granted. The State has flexibility 

under the CAA for a nonattainment area to consider impacts, such as these, as it develops 

the control strategy for the SIP to bring the area into attainment of the air quality 

standard.
Page 58 of 63

-Boiler MACT Implementation. One commenter discusses that Montana DEQ in 

2011 made a case that the implementation of this rule would significantly reduce SO2 at 

major sources. However, EPA dismissed this and stated that since the rule has been 

indefinitely delayed, anticipated reductions could not be factored into this initial 

designation and that the rule would not have a significant effect on the area. The 

reconsideration of EPA’s Boiler MACT standard for major sources was finalized and 

published as 40 CFR 63, subpart DDDDD on January 31, 2013. The commenter further 

discusses that even though exact reductions is still unknown, the assumption cannot be 

that SO2 reductions will be insignificant. Another commenter discusses that for subpart 

DDDDD, MSCC, PPL, ExxonMobil, CHS, and Phillips66 appear to meet the 

applicability requirements of the rule. The commenter continues that reduction in SO2 is 

not quantifiable at this early stage, but improvements in efficiency and tune-up will likely 

lead to slightly lower emissions. Additionally, the reconsideration of EPA’s Boiler 

MACT standard for area sources was finalized and published as 40 CFR 63, subpart JJJJJ 

on February 1, 2013. The commenter discusses subpart JJJJJ, where Western Sugar’s 

coal-fired boilers would be subject to Hg and CO limits. However, it is still unclear what 

steps Western Sugar may take to meet the Hg emission limits. If scrubber upgrades are 

considered for Hg control at Western Sugar, a co-benefit of SO2 emissions reductions 

will be realized.

EPA’s Response: The EPA agrees that exact SO2 emission reductions for the Boiler 

MACT implementation rule cannot be known at this time. However, the EPA has revised 

the initial nonattainment area to include only the Corette power plant and the violating 

monitor (see Region 8’s TSD). Thus the other sources and the areas that will show 

reductions from subpart JJJJJ and subpart DDDDD (except for PPL Corette) of the Boiler 

MACT rule are outside the scope of this initial nonattainment designation and will be 

addressed in a future final designations action. For PPL’s Corette power plant, the State 

has flexibility under the CAA for a nonattainment area to consider impacts, such as these, 

as it develops the control strategy for the SIP to bring the area into attainment of the air 

quality standard.

Comment: MEIC and Sierra Club support designation of all or a portion of Yellowstone 

County as a nonattainment area for the SO2 NAAQS, but believe that EPA must also 

designate all or a portion of Rosebud County as a nonattainment area for the SO2

NAAQS. The largest source in Rosebud County is Colstrip, and even with future 

reductions from the regional haze plan, violations of the 1-hour SO2 standard still occur. 

The commenters agree with EPA that ExxonMobil testing in 2010 is unavailing and since 

ExxonMobil is downwind of the monitor they are unlikely the sole cause of the 

violations. Additionally, MDEQ’s five-factor analysis proposal for only Corette in the 

nonattainment area (NAA) does not follow CAA requirements that all contributing 

sources to the violation be included in the NAA. Not one source is solely responsible for 

SO2 violations and in addition, other sources in the area emit the same or even more SO2

than Corette. From the modeling analysis, where conservative assumptions about the 

other sources emissions were assumed, Corette would need to reduce its SO2 emissions 

by more than 88%. In support of these comments, MEIC and Sierra Club submit 

modeling of SO2 NAAQS violations in Yellowstone and Rosebud Counties, where the 
Page 59 of 63

modeling predicted that exceedances would extend throughout the region and up to a 

distance of 50km from the sources (but excluding the Crow Reservation). This modeling 

is appropriate because Yellowstone County contains only one SO2 monitor and Rosebud 

County contains none. EPA is required to consider all evidence before it—including 

submitted modeling—in making attainment and nonattainment designations.

EPA’s Response: The EPA agrees with the commenter that a portion of Yellowstone 

County should initially be designated nonattainment. However, EPA is not yet prepared 

to conclude whether Rosebud County should be designated in whole or in part 

nonattainment based on a modeling analysis. In this initial round of final nonattainment 

designations, the EPA is not addressing modeling either in the initial nonattainment areas 

or in other areas, which will be addressed in a future round of final designations. Thus 

Rosebud County and the remaining portion of Yellowstone County are outside the scope 

of this initial nonattainment designation, and will be addressed in a future final action, 

which could include determining whether initial nonattainment boundaries need to be 

extended, new nonattainment boundaries need to be designated, or if the areas should be 

designated attainment or unclassifiable. Region 8’s TSD provides a more detailed 

analysis of revising Yellowstone County’s nonattainment boundary under sections “Air 

Quality Data” and “Emissions and Emissions-Related Data” based on monitoring data.

3.2.9. Multi-Region Areas 

3.2.9.1. Campbell-Clermont Counties, KY-OH Area

Comment: In a March 6, 2013, letter, the Commonwealth of Kentucky submitted a 

response to EPA’s February 6, 2013, intended nonattainment designation and boundary 

determinations for areas in relation to the 2010 SO2 NAAQS. Kentucky expressed strong 

opposition to any portion of Campbell County, Kentucky being designated 

nonattainment. Specifically, the Commonwealth stated “... Kentucky strongly opposes 

the proposed nonattainment designation of Campbell County due to overwhelming 

supporting data indicating that there is no environmental benefit to designating the 

Kentucky portion as nonattainment.” Kentucky cited to EPA’s TSD which explained that 

the source causing the violation at the Campbell County, Kentucky monitor is in 

Clermont County, Ohio. The Commonwealth provided some general technical points 

implicating the source in Clermont County as causing the violation at the monitor in 

Kentucky, and mentioned that the nonattainment designation for Campbell County would 

cause more stringent permitting requirements and would not result in any additional 

programs in Campbell County, Kentucky to reduce SO2 emissions. Also, Kentucky 

noted that “... the total area in Kentucky designated nonattainment is ironically larger 

than the total area designated nonattainment in Ohio, the location of the source causing 

the violation.”

EPA’s Response: The EPA has made the determination that Campbell County, 

Kentucky has a violating monitor for the 1-hour SO2 NAAQS, and thus is designating a 

portion of this county as nonattainment. Additionally, and in association with the 

violating monitor in Campbell County, Kentucky, the EPA is also designating a portion 
Page 60 of 63

of Clermont County, Ohio as nonattainment for the 1-hour SO2 NAAQS. Because of the 

nonattainment designation, the Commonwealth of Kentucky is obligated under the CAA 

to submit a State Implementation Plan for the Campbell County area. However, the EPA 

understands that for the Campbell County, Kentucky nonattainment area, the emissions 

source associated with the violation monitored in Campbell County is located in Ohio. 

Accordingly, we expect Ohio will address this source as part of their state 

implementation planning. The EPA will work with Ohio to ensure the required 

nonattainment area SIP addresses the air quality impact on the citizens of Kentucky. 

With regard to size of the boundary for the Kentucky portion of this area, the EPA has 

reevaluated its intended boundary determination, and has revised this boundary. More 

information on EPA’s technical analysis for this area and revised boundary determination 

for Campbell County, Kentucky can be found in EPA’s TSD for Kentucky.

3.2.9.2. Steubenville, OH-WV Area

Comment: The WV Division of Air Quality (DAQ) has performed additional technical 

analysis and refined the related nonattainment area boundaries. Therefore, we are now 

recommending that EPA revise its initial Nonattainment Area Designations for West 

Virginia. Our recommendations are primarily based upon the five-factor analysis detailed 

in EPA's March 2011 guidance. In the Steubenville OH-WV area, all of the violating 

monitors in Brooke County WV and all significant sources of SO2 emissions in Brooke 

County WV are located in the Cross Creek Tax District portion of Brooke County, WV. 

The West Virginia portion of the Steubenville, OH-WV non attainment area should be 

confined to the Cross Creek Tax District (within Brooke County). 

EPA’s Response: EPA concurs with this recommendation from DAQ. The additional 

information regarding monitor locations and emissions information (Tables 5 and 6 of the 

DAQ Five factor analysis document and related discussion in this document) was 

confirmed by EPA and supports a revised boundary for the WV portion of this 

nonattainment area specifically using a partial county boundary of Brooke County 

consisting of the Cross Creek Tax District. See the WV TSD for additional information.

3.2.9.3. Marshall, WV Area (previously called Wheeling, WV-OH)

Comment: The WV Division of Air Quality (DAQ) has performed additional technical 

analysis and refined the related nonattainment area boundaries. Therefore, we are now 

recommending that EPA revise its initial Nonattainment Area Designations for the West 

Virginia portion of this area. Our recommendations are primarily based upon the fivefactor analysis detailed in EPA's March 2011 guidance. The West Virginia portion of the 

Wheeling, WV-OH nonattainment area should be confined to the Clay, Franklin and 

Washington Tax Districts all within Marshall County.

EPA’s Response: EPA concurs with this recommendation from DAQ. The additional 

information from DAQ indicates that the violating monitor in Marshall county is located 

in the Washington Tax District and all significant SO2 emission sources are located in 

Franklin Tax District (Tables 7 and 8 of the DAQ five factor analysis and related 
Page 61 of 63

discussion in this document). Clay tax district is located directly between Franklin and 

Washington Tax Districts. This information supports a revised boundary for the WV 

portion of this nonattainment area specifically using a partial county boundary of 

Marshall County consisting of the Clay, Franklin, and Washington Tax Districts within 

Marshall County. See the WV TSD for additional information.

Comment: The DAQ analysis indicates that a nearby significant source, which likely 

impacts the above area, seems to have been overlooked. Therefore, we recommend that 

Ohio Township (Monroe County, OH) be included in the final Wheeling, WV-OH 

nonattainment designation since it contains The Ormet Primary Aluminum facility. This 

facility is located less than 5 kilometers from the PPG Industries facility which is located 

in the recommended nonattainment area. 

EPA’s Response: The Ormet SO2 source in Ohio Township, Monroe County, Ohio, is 

located approximately 25 km from the Marshall County, WV, monitor. As discussed by 

DAQ and confirmed by EPA this source emitted 2,442 tpy of SO2 in 2008 and 2,471 tpy 

in 2011 (2008 NEI and draft 2011 NEI). As discussed in the TSD that accompanied this 

proposal, PPG Industries emitted 7,693 tpy (2008 NEI). Also while the Ormet facility is 

in close proximity to the PPG Industries facility, PPG Industries emits almost three times 

the amount of SO2 emissions as Ormet and is also located within a jurisdictional border 

that is useful for bounding the nonattainment area. EPA did not propose to include the 

Ormet facility in the original nonattainment area and is not prepared based on the 

emissions information and other factors to include this source in the initial nonattainment 

area. We will make final designation decision for areas outside the Marshall County WV 

area in a subsequent round of designations. See the WV TSD and Ohio TSD for 

additional information. 

Comment: The WV Division of Air Quality (DAQ) has performed additional technical 

analysis and recommends that EPA retain Mead Township in Belmont County Ohio in 

the Wheeling WV-OH Nonattainment Area. In particular although R.E. Burger power 

plant has ceased operations, emissions from this plant appear to have significantly 

impacted the air quality in Marshall County, WV during three year periods when 

monitored data showed violations of the NAAQS. 

EPA’s Response: EPA does not concur with this recommendation and is removing 

Mead Township from the nonattainment area. Additional information that responds to 

this comment can be found in our response to comment below which addresses a 

comment from Scott Nally of the Ohio Environmental Protection Agency. Additional 

information can be found in the Ohio and WV TSDs. 

Comment: EPA is proposing to designate a portion of Belmont County, Ohio, 

nonattainment as part of the Wheeling WV-OH nonattainment area, as a result of 

violations occurring at a monitor in West Virginia. Upon further review of this 

recommendation, Ohio EPA urges EPA to designate all of Belmont County as 

unclassifiable. As recognized in both the West Virginia and Ohio technical support 

documents supplied by EPA, the only source in Ohio that may have been a significant 
Page 62 of 63

source is the R.E. Burger power plant. As indicated in Table 9 of Ohio’s TSD, R.E. 

Burger represented just over 15,000 tpy out of over 66,700 tpy in the area in 2008. At 

that time the monitor in Ohio was at 105 ppb while the monitor in West Virginia was at 

113 ppb. Since that time, emissions have decreased at the R.E. Burger plant to zero 

emissions in 2011 and 2012. This is the result of the permanent shutdown of two larger 

units (156 MW each) and the cold storage of two smaller units (94 MW each). Since the 

shutdown and cold storage, the Ohio monitor has shown attainment while the West 

Virginia monitor has continued to show nonattainment. It is Ohio’s belief that any future 

consideration of Belmont County sources should be a part of the upcoming unclassifiable 

planning; therefore, we recommend an unclassifiable designation for all of Belmont 

County.

EPA’s Response: EPA has reviewed the SO2 emissions data reported to the Clean Air 

Markets Division (CAMD) for the R.E. Burger plant, 2005-2012. These data confirm the 

emissions information in Ohio’s comment. 

The First Energy R.E. Burger power plant, in Shadyside, Ohio, is located two kilometers 

from the Marshall County monitor in Moundsville, West Virginia, and about seven 

kilometers from the Belmont County monitor. Given this proximity, EPA carefully 

evaluated this source as a potential contributor to the monitored SO2 concentrations. On 

March 13, 2013, Ohio informed EPA that the R.E. Burger power plant had emitted no 

SO2 in 2011 or 2012. Two of its four units (Units 7 and 8) had shut down permanently 

and enforceably in 2010. The remaining two smaller units (Units 5 and 6) are in cold 

storage. Cold storage is not a federally enforceable shutdown; those units currently retain 

the legal right to restart without obtaining a new permit. However, as discussed below, 

EPA believes that these units are unlikely to resume operation, and furthermore EPA 

believes that these units are unlikely to operate at a level that would warrant treating the 

source as contributing to the violation at the Marshall County monitor. In 2011, when the 

R.E. Burger power plant reported zero SO2 emissions to EPA CAMD, the Moundsville 

monitor still exceeded the 2010 SO2 NAAQS (79 ppb).

The table below shows the SO2 emissions for Units 5 and 6 at the R.E. Burger power 

plant as reported to CAMD for the years starting in 2005. While these units had 

emissions of several hundred tons each in 2005 and 2007, emissions for all other years 

since 2005 have been under 100 tons for each unit, with emissions in most years being 

zero. By comparison, the larger two units at R.E. Burger (Units 7 and 8) emitted a 

combined total of 14,952 tons in 2008, a level that was close to average for these units for 

the years before they shut down by the beginning of 2011. These emissions from these 

larger units are prohibited from recurring by the permanent and enforceable shutdown of 

these units. The only emissions which might hypothetically resume are from Units 5 and 

6, the smaller units at the plant, which have been effectively shut down since 2008, and 

which historically emitted less than ten percent, and most recently no more than about 

one percent, of the larger units’ SO2 emissions. It is unlikely that the two smaller units 

will restart, and if they do, they are unlikely to contribute significantly to the 

nonattainment values. Since these units were shut down before the larger units were shut 

down, and since these units have been in cold storage for two years after the larger units 
Page 63 of 63

were shut down, the shutdown of the larger units is not expected to result in load being 

shifted to the smaller units. The requirements of the Clean Air Interstate Rule (CAIR), 

which would make it even more expensive to operate these units, provide added incentive 

for FirstEnergy to continue keeping these units inoperative. Ohio provided further 

information about this facility in May 2013. Ohio staff spoke with representatives of 

FirstEnergy, who confirmed that they have no intention of restarting Units 5 and 6. The 

company is keeping the two units in “cold storage” rather than permanently shutting them 

down in order to maintain receiving allowances for use in other facilities, and for the 

income tax advantages of retaining the units on cold storage status. Units 5 and 6 are 63 

years old, the R.E. Burger power plant currently has no coal onsite, and economics 

dictate that FirstEnergy is unlikely to restart these units. Therefore, EPA believes that the 

R.E. Burger power plant is not currently contributing and is not likely to contribute in the 

future to the Marshall WV nonattainment area, and EPA agrees with Ohio’s 

recommendation that Mead Township, Belmont County, should not be designated 

nonattainment for the 2010 SO2 NAAQS.

Table. Annual SO2 Emissions for Units 5 and 6 at the R.E. Burger Power Plant (As 

reported to CAMD)

Unit ID Year SO2

(tons)

Heat Input 

(MMBtu)

5 2005 433.5 236316.6

6 2005 347.1 190433.0

5 2006 0 0

6 2006 0 0

5 2007 723.2 506796.2

6 2007 671.2 471102.9

5 2008 81.3 69613.9

6 2008 93.2 79246.6

5 2009 0 0

6 2009 0 0

5 2010 3.0 2483.4

6 2010 2.7 2239.9

5 2011 0 0

6 2011 0 0

5 2012 0 0

6 2012 0 0