Appendix C 

Public Notice Report, Comments 

Received and Responses 
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Public Notice Report, Comments Received and Responses 1 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area Appendix C 

Redesignation Demonstration and Maintenance Plan November 2, 2011 

Public Notice Report 

For the 

Redesignation Demonstration and Maintenance Plan 

for The Charlotte-Gastonia-Rock Hill, North Carolina –South Carolina 

1997 8-Hour Ozone Nonattainment Area 

Introduction 

On May 18, 2011, a draft version of the “Redesignation Demonstration and Maintenance Plan 

for the Charlotte-Gastonia-Rock Hill, North Carolina –South Carolina 1997 8-Hour Ozone 

Nonattainment Area” was submitted to the United States Environmental Protection Agency 

(USEPA). A request for public hearing, in accordance with 40 CFR 51.102, and the public 

comment period were noticed in the local newspaper on Thursday, May 19, 2011. The public 

comment period was open from May 20, 2011 through June 23, 2011. No requests for a public 

hearing were received, so the hearing that had been scheduled for June 23, 2011, was cancelled 

and noticed on the North Carolina Division of Air Quality (NCDAQ) website on June 21, 2011. 

The public comment period elicited comments from the USEPA, Cabarrus Rowan Metropolitan 

Planning Organization (CRMPO) and the Mecklenburg Union Metropolitan Planning 

Organization (MUMPO). 

Background 

The area surrounding Charlotte-Gastonia-Rock Hill, North Carolina-South Carolina (i.e. the 

Metrolina area) was designated nonattainment for the 1997 8-hour ozone National Ambient Air 

Quality Standard (NAAQS) on April 30, 2004 (69 Federal Register 23858). The Metrolina 

nonattainment area includes the North Carolina counties of Cabarrus, Gaston, Lincoln, 

Mecklenburg, Rowan and Union; Coddle Creek and Davidson Townships in Iredell County, 

North Carolina; and the Rock Hill Metropolitan Planning Organization boundary in York 

County, South Carolina. The nonattainment designation was an action taken by the USEPA 

under Section 107(d) of the Clean Air Act (CAA). The CAA requires that some area be 

designated as nonattainment if a monitor is found to be in violation of a NAAQS. The USEPA 

took designation action in 2004 based on the ambient data from 2001-2003. At that time, the 

regional design value, the highest monitor’s design value, was 0.100 parts per million (ppm). 

There are currently seven ozone monitors located throughout the Metrolina nonattainment area 

and one monitor located in York County, South Carolina, just outside of the nonattainment area. 

The latest design value for the nonattainment area is 0.082 ppm based on the data from 2008-

2010, and is therefore in attainment of the 1997 8-hour ozone NAAQS, and the area is eligible to 

be considered for redesignation to attainment. 

The State of North Carolina has implemented permanent and enforceable reductions in ozone 

precursor emissions in the Metrolina area. These actions include implementing the on-board 

diagnostic vehicle inspection and maintenance program that was phased-in in the Metrolina 

nonattainment area from July 1, 2002 through January 1, 2004, and an open burning ban during 
Public Notice Report, Comments Received and Responses 2 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area Appendix C 

Redesignation Demonstration and Maintenance Plan November 2, 2011 

ozone action days. In addition, there have been several State rules that have resulted in 

reductions in emissions in nearby areas that have resulted in lower ozone levels at the monitor. 

These State actions include the NOx SIP Call rules and the Clean Smokestacks legislation. 

Finally, several actions at the Federal level by the USEPA have resulted in lower emissions 

throughout the eastern portion of the country. These Federal actions include the Tier II engine 

standards for light and medium duty vehicles, heavy-duty engine standards, the low sulfur 

gasoline and diesel requirements, off-road engine standards, the NOx SIP Call and the Clean Air 

Interstate Rule (CAIR). CAIR was remanded by the court and although North Carolina did not 

rely on the emission reductions from CAIR for maintenance of the 1997 8-hour ozone standard, 

CAIR will result in additional reductions in NOx emissions regionally. 

North Carolina is requesting that the USEPA redesignate the Metrolina nonattainment area to 

attainment. The monitoring data clearly shows that the region has attained the 1997 8-hour 

ozone standard, and the maintenance demonstration shows that the future emission inventories 

are expected to be lower than the base year inventory through the implementation of the various 

control measures listed above. 

Summary of Public Comment Period 

The public notice comment period was open from May 20, 2011 through June 23, 2011. There 

were no requests for a public hearing so the hearing scheduled for June 23, 2011, was cancelled. 

Comments were received from the USEPA, the CRMPO and the MUMPO, which are attached 

following this report along with the NCDAQ’s response to comments letter to the USEPA. 

The following is a summary of the pertinent comments raised during the public comment period, 

along with the NCDAQ’s response. A number of the comments received by the USEPA were 

minor, mostly requesting clarifying language be added to the SIP documentation. The NCDAQ 

has added the clarifying language to address the minor comments therefore, these comments are 

not discussed below. 

CRMPO comment: The Cabarrus-Rowan Transportation Advisory Committee voted 

unanimously on June 22, 2011 to endorse options B and C for setting the geographic extent of 

the Motor Vehicle Emission Budgets as part of the recently released Metrolina 

Redesignation/Maintenance Plan. 

NCDAQ response: The NCDAQ will take this comment into consideration along with the other 

comments received regarding MVEBs. The final documentation will outline the comments 

received and how these comments were used to make the final option selection. 

MUMPO comment: Select a motor vehicle emission budget strategy that does not treat 

Mecklenburg County as a planning entity separate from the rest of the Metrolina Region. 

Mecklenburg County should be treated in a manner consistent with that of the rest of the region 

with regard to MVEB. 

NCDAQ response: The NCDAQ will take this comment into consideration along with the other 

comments received regarding MVEBs. The final documentation will outline the comments 

received and how these comments were used to make the final option selection. 
Public Notice Report, Comments Received and Responses 3 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area Appendix C 

Redesignation Demonstration and Maintenance Plan November 2, 2011 

MUMPO comment: Consider an alternative “Option E” which consists of one budget for the 

Cabarrus-Rowan MPO and one budget for the rest of the Metrolina region. While a true regional 

budget is the preferred option, “Option E” is identical to the geographic distribution agreed upon 

in writing by all of the Metrolina MPOs [Metropolitan Planning Organizations], RPOs [Rural 

Planning Organizations] and NCDOT [North Carolina Department of Transportation] in 2006. 

NCDAQ response: In 2006, the NCDAQ asked transportation partners to provide feedback 

with regards to either county level budgets or regional budgets, and the response referred to in 

MUMPO’s comment were in response to that request. The draft maintenance plan provided a 

number of options that addressed the concerns the NCDAQ had in 2006 as well as addressing 

concerns provided by the transportation partners at that time. The NCDAQ did not receive 

feedback from the other transportation partners during this public comment process stating that a 

regional budget is still the preferred approach or if one of the other options provided addressed 

their concerns sufficiently. Additionally, the NCDAQ asked transportation partners during the 

interagency consultation process, prior to developing the maintenance plan, to provide feedback 

about alternative ways to establish MVEBs and only two MPOs responded. CRMPO requested a 

single MVEB for its MPO and MUMPO requested a single budget for its MPO. Therefore, the 

NCDAQ will not be establishing MVEBs consistent with MUMPO’s “Option E”. 

MUMPO comment: Do not apply county-level MVEBs to those portions of the Metrolina 

regions not requesting them. MUMPO is aware that Cabarrus and Rowan Counties have stated 

(and may still have) a preference for county-level MVEBs, but the remainder of the Metrolina 

region has not expressed such a preference. MUMPO based this recommendation, in part, on 

their belief that MVEB is a tool for conformity, not a tool for attainment. They stated 

“Attainment of the ozone standard is independent of our transportation conformity status. 

Though the MVEB is part of the SIP [State Implementation Plan], and the MVEB will be used 

for transportation conformity, the MVEB are not considered a tool to attaining the air quality 

standard.” 

NCDAQ response: Although the NCDAQ will take this comment, along with the other 

comments received regarding MVEBs, into consideration when establishing the MVEBs for the 

Metrolina area, the NCDAQ does not agree with MUMPO’s assertion that MVEBs are 

independent of attainment/maintenance of the air quality standards. The whole purpose of 

transportation conformity is to ensure that federal actions (such as transportation funding) will 

not hinder an area from attaining and/or maintaining an air quality standard. Therefore, it would 

be appropriate to treat a planning entity separate from the rest if doing so would provide 

additional assurance that the area would not violate the standard due to motor vehicle emissions 

increases due to transportation projects in that area. 

MUMPO comment: Allocate the same percentage for MVEBs to Mecklenburg County as 

allocated to Cabarrus, Gaston, Union and Rowan Counties. NCDAQ’s treatment of an 

“emissions dominant” county appears to be inconsistent with how NCDAQ treated Wake County 

in the Triangle Region’s 2007 ozone maintenance SIP. Also, the percentages of safety margin 

assigned to each county appear in the draft SIP summary table to be 5% less than they should be. 

Finally, the draft SIP is not clear how much of the total safety margin may be allocated in 

practice if the need arises. 
Public Notice Report, Comments Received and Responses 4 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area Appendix C 

Redesignation Demonstration and Maintenance Plan November 2, 2011 

NCDAQ response: The NCDAQ does not believe that it is appropriate to compare the percent 

used to determine the amount of safety margin allocated to the MVEB for Wake County with the 

percent used for Mecklenburg County. Mecklenburg County’s 2013 Nitrogen Oxides (NOx) 

emissions are 52.05 tons per day, which are a significantly higher than any other county’s onroad mobile source emissions in the State, including Wake County. Additionally, the air quality 

was cleaner in Wake County when the MVEBs were established than it currently is in 

Mecklenburg County. The regional design value for Triangle area in 2007 was 0.080 parts per 

million (ppm) with the fourth highest maximum 8-hour ozone value of 0.078 ppm in Wake 

County. The regional design value for the Metrolina area is 0.082 ppm and the fourth highest 

maximum 8-hour ozone concentration in Mecklenburg County is 0.082 ppm. Furthermore, in 

the 2011 ozone season thus far, a total of eight exceedances of the 1997 8-hour ozone standard 

have occurred in the Metrolina region, six of which have occurred in Mecklenburg County. So 

although the Metrolina has attained the 1997 8-hour ozone standard, there are still exceedances 

of the standard in this area, more than any other area in the State and on-road mobile source 

emissions are a significant contributor to the NOx emissions. Finally, the current air quality 

situation is different now than when the MVEBs were established for Wake County in 2007. In 

2007, the 8-hour ozone standard was 0.08 ppm. Currently the 8-hour ozone standard, established 

in 2008, is 0.075 ppm. The USEPA is reconsidering this standard and is expected to promulgate 

a new standard in 2011 that will most like be even lower. The NCDAQ took all of this into 

consideration when establishing how much safety margin was allocated to the MVEBs. 

USEPA comment: Reasonable Available Control Technology [RACT] – Section 182(b)(2) of 

the Clean Air Act requires RACT controls for all sources addressed by CTGs in areas classified 

moderate and above. For the Charlotte 1997 8-hour ozone nonattainment area, these rules would 

have to be submitted and approved in order for the redesignation to be approved. Not addressing 

RACT for sources with emissions less than 100 tons per year is not consistent with this 

requirement. 

NCDAQ response: The NCDAQ learned recently that the USEPA had concerns with North 

Carolina’s applicability rule for RACT (15A North Carolina Administrative Code (NCAC) 

2D.0902) which was submitted to the USEPA for adoption in to the North Carolina SIP in April 

2007 and again in January 2008. The NCDAQ will work with the USEPA to address their 

concerns with the Metrolina RACT SIP as quickly as possible. 

USEPA comment: The plan states that several rules addressing volatile organic compounds 

have been adopted for toxics purposes and have been submitted for inclusion in the SIP. 

However, the redesignation request states that applicability for the Charlotte Area is only state 

effective and has not been submitted to U.S. Environmental Protection Agency for federal 

approval and is not federally enforceable. Having RACT for several CTG categories be only 

state enforceable is inconsistent with the statutory RACT requirement for CTG sources cited 

previously. Please make the clarification that the rules have been or will be submitted for federal 

approval. 

NCDAQ response: The wording in the draft redesignation request was incorrect. The 

applicability of the rules the USEPA is referring to were federally approved into the SIP in 

August 2001. Additionally, the applicability rule mentioned above (15A NCAC 2D .0902) was 
Public Notice Report, Comments Received and Responses 5 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area Appendix C 

Redesignation Demonstration and Maintenance Plan November 2, 2011 

submitted to the USEPA for adoption into the SIP in April 2007 and in January 2008. These 

submissions include the statewide applicability of the rules referred to by the USEPA. This error 

has been corrected. 

USEPA comment: – Contingency Plan – The contingency plan section should be strengthened 

to meet the requirements of Clean Air Act section 175A and the September 4, 1992, EPA 

Redesignation Guidance (Procedures for Processing Requests to Redesignate Areas to 

Attainment, aka, the Calcagni memo). The Calcagni Memo states that “The plan should clearly 

identify the measures to be adopted, a schedule and procedure for adoption and implementation, 

and a specific time limit for action by the State.” EPA has consistently required that adoption 

and implementation of contingency measures be completed within 18 to 24 months from a 

trigger. ... ... ... The plan only states that North Carolina commits to implement within 24 

months at least one of the measures. Please ensure that the contingency measure adoption 

schedule is abundantly clear that the state commits to adopt one of the measures indicated in the 

plan within 24 months of a trigger, regardless of whether or not legislative review is required. 

NCDAQ response: The wording has been changed to state “The NCDAQ commits to 

implement within 24 months of a primary or secondary trigger, or as expeditiously as 

practicable, at least one of the control measures listed above or other contingency measures that 

may be determined to be more appropriate based on the analyses performed.” 

USEPA comment: Page 3-12, Section 3.3.2 - There is no discussion whether or not the 2010 

emissions inventory represents actual point source emissions as required for a redesignation. 

From Appendix B.1, it appears that the 2009 actual point source emissions were projected to 

2010 for the base year inventories. The point source inventory for the 2010 baseline inventory 

should represent actual emissions for 2010. Please clarify that the 2010 point source emissions 

in the redesignation meet this requirement and that actual 2010 emissions were used where 

available, particularly for significant point sources. 

NCDAQ response: The actual 2010 point source emissions inventory will not be available until 

December 2011. However, for the facilities that report to the USEPA’s Clean Air Markets 

Division (CAMD), significant point sources for NOx emissions, the NCDAQ used the actual 

2010 data from the CAMD database. For the remaining major sources, the latest available data 

from 2009 was used and grown to 2010 using the USEPA’s EGAS (Economic Growth Analysis 

System) growth projection model. The NCDAQ believes this inventory used for the 

maintenance plan is representative of 2010 emissions. 

USEPA Comment: Page 4-2, Section 4.3 – Of the four motor vehicle emissions budget 

(MVEBs) options presented in the prehearing, EPA prefers option A which sets separate budgets 

for each county. If Option B or D is ultimately chosen, it should be clarified that the additional 

Mecklenburg County budgets are sub-budgets of the overall MPO/RPO budget which also 

includes Mecklenburg County. Currently, it could appear that the additional Mecklenburg 

budget is a separate budget. The final redesignation submittal should indicate how public 

comments were used to make the option selection. 

NCDAQ response: The NCDAQ appreciates the USEPA comments regarding the 

establishment of MVEBs. The NCDAQ will take this comment into consideration along with 
Public Notice Report, Comments Received and Responses 6 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area Appendix C 

Redesignation Demonstration and Maintenance Plan November 2, 2011 

the other comments received by transportation partners. The final documentation will outline the 

comments received and how these comments were used to make the final option selection. 

Conclusion 

After considering the comments received, the NCDAQ has chosen to establish MVEBs based on 

Option C. This option set MVEBs as grouped counties based on counties that contain a 

Metropolitan Planning Organization (MPO) and/or Rural Planning Organization (RPO). This 

option is consistent with the CRMPO request and takes into consideration two of the comments 

from MUMPO. The NCDAQ believes that this option is a good compromise between how 

MVEBs have been established in the past, addressing the NCDAQ’s concern with Mecklenburg 

County’s on-road mobile source emissions and the preferences of the transportation partners. 

Further, the NCDAQ believes this approach provides additional flexibility to the transportation 

partners while providing adequate assurance that the ozone standard will be maintained in the 

region. Therefore, MVEBs will be set for the CRMPO (Cabarrus and Rowan Counties), for the 

Gaston Urban Area MPO and Lake Norman RPO (Gaston, Iredell, and Lincoln Counties), and 

for the MUMPO and Rocky River RPO (Mecklenburg and Union Counties). 

Attachments to Public Notice Report 

1) Written comments received from Phil Conrad on behalf of the Cabarrus Rowan MPO dated 

June 23, 2011. 

2) Written comments received from William S. Coxe, Chair of the Mecklenburg Union MPO 

Technical Coordinating Committee dated June 22, 2011. 

3) Written comments from Richard A. Schutt, Chief of the Air Planning Branch, USEPA, 

dated June 23, 2011. 

4) NCDAQ’s written response to the USEPA’s comments, dated June 29, 2011. 

5) Public notice language dated May 17, 2011. 

6) The Charlotte Observer Publishing Company publication affidavit of public notice. 
Boothe, Laura

From: Phil Conrad [pconrad@mblsolution.com]

Sent: Thursday, June 23, 2011 9:19 AM

To: SVC_DENR.DAQ.publiccomments

Cc: Boothe, Laura; Joe Wilson; Connie Cunningham

Subject: Metrolina Redesignation

The Cabarrus-Rowan Transportation Advisory Committee voted unanimously on June 22, 2011 to

endorse options B and C for setting the geographic extent of the Motor Vehicle Emission Budgets as

part of the recently released Metrolina Redesignation/Maintenance Plan. We appreciate the 

opportunity to comment on this important state decision and look forward to participating as a

stakeholder in future discussions on the SIP. 

If you should have any questions, please do not hesitate to let us know. 

Sincerely, 

Phil Conrad 

Cabarrus-Rowan MPO 

135 Cabarrus Avenue East 

Concord, North Carolina 28025

704-795-7528

704-795-7529 fax 

www.crmpo.org

From: Boothe, Laura [mailto:laura.boothe@ncdenr.gov] 

Sent: Monday, May 23, 2011 8:17 AM 

Subject: Metrolina Redesignation Demonstration out for comment

Good Morning everyone

The Metrolina Redesignation Demonstration and Maintenance Plan is out for public comment.  The

notice was published in the Charlotte Observer either Thursday or Friday last week.  The comment

period goes through June 23rd.  Requests for a public hearing must be received by June 20th (see public

notice on website below for information about requesting public hearing).  If no request for a public

hearing is received then the public hearing scheduled for June 23rd will be cancelled and noticed on the

DAQ website.

http://ncair.org/planning/Metrolina_Redesignation_Maintenance.shtml

Please let me know if you have any questions

Laura  

Please notice my e‐mail address has changed to: Laura.Boothe@ncdenr.gov

Laura Boothe

Attainment Planning Branch Supervisor

NCDENR, Division of Air Quality

1641 Mail Service Center

Raleigh, NC 27699‐1641

(919) 733‐1488

(919) 715‐7476 FAX

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 7 

 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 8 

 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 9 

 Appendix C 

November 2, 2011
ATTACHMENT 

Data and Detailed Discussion Supporting Comments on the CharlotteGastonia-Rock Hill 1997 8-Hour Ozone Nonattainment Area PreHearing Draft Redesignation Demonstration and Maintenance Plan

On behalf of The Mecklenburg-Union Metropolitan Planning Organization (MUMPO) I 

want to thank the Division of Air Quality for allowing this opportunity to comment on 

the Ozone SIP draft document dated May 18, 2011 (hence identified as the “draft SIP”). 

Getting to this point has been a regional effort. Industries, municipalities, and regional 

planning organizations, worked toward a common goal of cleaner air based on the SIP. 

The ozone air quality, and the emissions of anthropogenic precursors to ozone, have all 

trended downward since 2000. MUMPO believes the mechanism has been – and will 

remain -- in place to continue those trends. Of particular note, decreasing emissions of 

NOx from the transportation sector have been the result of technological advances 

mandated on the federal level. NOx and VOC emissions have been projected to decrease 

in every county in the region, including Mecklenburg County, in spite of projected 

increases in population and vehicle miles traveled (VMT). This has been documented not 

only in all of MUMPO’s Transportation Conformity Documents since 2002, but is also 

reflected in the emissions NCDAQ projected in the draft SIP for every county of the 

Metrolina region, including Mecklenburg County. 

Because MUMPO is one of three Metropolitan Planning Organizations charged with 

developing regional transportation planning documents which must conform to the limits 

in the Motor Vehicle Emissions Budgets (MVEBs) contained in the SIP, our comments 

are largely related to those MVEBs. 

The detailed comments in this attachment are divided into four sections, corresponding to 

the comments in the cover letter. Also, for the sake of brevity, our comments are largely 

limited to NOx emissions, but our comments would also apply to VOC emissions. To that 

end, we believe the following comments are in the best interest of MUMPO, and the 

Metrolina region as a whole, for sustainable regional growth, for transportation planning, 

and for enabling the region to continue to meet the 1997 ozone NAAQS over the next 

decade. All referenced figures are shown at the end of this attachment. 

 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 10 

 Appendix C 

November 2, 2011
 Page 2 of 18

Comment #1 Separate Treatment of Mecklenburg County 

MUMPO is concerned that the NCDAQ finds it necessary to create a separate MVEB for 

Mecklenburg County. The geographic distribution options in the draft SIP send a clear 

message that somehow Mecklenburg County has the potential to cause or contribute to 

air quality problems in the future. In discussing Option B, and also Option D, the 

rationale given in the draft SIP is: 

“Since Mecklenburg County’s motor vehicle emissions are almost five times 

larger than the next closest county’s emissions and the monitors in and downwind 

of Mecklenburg County tend to have the highest ambient ozone concentrations, 

the NCDAQ is recommending these emissions be managed differently.” 

MUMPO does not believe these reasons for such management to be either significant or 

relevant. It is not clear from the SIP narrative exactly what NCDAQ hopes to accomplish 

by managing Mecklenburg County emissions differently from the rest of the region. The 

fact that Mecklenburg County’s motor vehicle emissions are almost five times larger than 

the next closest county’s emissions does not in itself constitute a threat to air quality. 

Mecklenburg County motor vehicle emissions are decreasing, and thus is not a potential 

hindrance to possible future growth in surrounding counties. Regarding the monitors, 

NCDAQ intended 5 of the region’s 7 ozone monitors to be downwind of Mecklenburg 

County, so it is no surprise that these monitors would generally record the highest ozone. 

But of more significance is that all of the monitors are now attaining the ozone NAAQS. 

NCDAQ’s own data in the draft SIP strongly suggests that any threat to maintaining the 

1997 ozone standard will decrease in the future because emissions of NOx and VOC will 

continue to decrease in the future. Therefore, there is no reason for Mecklenburg County 

motor vehicle emissions to be “managed differently.” 

Regarding the magnitude of Mecklenburg County’s motor vehicle NOx emissions, 

MUMPO presents the following to clearly show that Mecklenburg County motor vehicle 

NOx emissions do not pose now, and will continue to not pose a threat to either the 1997 

ozone NAAQS, or to the economic development of the other counties in the Metrolina 

region: 

 

1. Conformity analyses between 2002 and 2011 consistently show motor vehicle 

emissions within Mecklenburg County decreasing for the foreseeable future. 

2. Mecklenburg County population, households, and employment are projected 

to become a smaller percentage of the Metrolina totals between 2011 and 

2035. 

3. NCDAQ’s own data show that motor vehicle emissions in Mecklenburg 

County will decrease from 2011 to at least 2022, in spite of an increase in 

VMT during that same period. 

For these reasons, discussed in greater detail below, Mecklenburg County motor vehicle 

emissions should not be managed differently. 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 11 

 Appendix C 

November 2, 2011
 Page 3 of 18

1. Conformity analyses between 2002 and 2011 consistently show motor vehicle 

emissions within Mecklenburg County decreasing for the foreseeable future. 

The projected NOx emissions for Mecklenburg County from conformity analyses from 

2002 through 2011 are displayed in Figure 1. Each symbol on the graph represents the 

projected NOx emissions for a specific horizon year. Some horizon years have been 

evaluated in multiple conformity analyses. All of the projected VMT had been reviewed 

vigorously by NCDAQ. All of the projected emissions have been calculated by NCDAQ. 

All of the projections except for the 2011 conformity analysis are from conformity 

documents approved by USDOT and by EPA. (The 2011 conformity analysis is still in 

public review until June 30). It is worth noting that this period includes conformity 

analyses made while Mecklenburg County was a maintenance area for the 1-hour ozone 

standard, and before the 8-hour non-attainment area was established. While over the 

years the assumptions and procedures have evolved, the aggregated historical trend is 

evident. Mecklenburg County motor vehicle NOx emissions have been decreasing and 

are projected to continue to decrease. 

Figure 2 is a graph of Mecklenburg County VMT and projected motor vehicle NOx 

emissions from 2000 to 2035. Again, the projected VMT had been reviewed by 

NCDAQ, and the NOx emissions calculated by NCDAQ. There is no evidence that 

somehow Mecklenburg County motor vehicle NOx emissions may increase, even though 

VMT is projected to increase. 

Figure 3 is a graph of the Mecklenburg County projected NOx for horizon years 2000, 

2005, and 2010 (as the dashed line) from Figure 2, overlaid with the annual 4th-highest 

ozone in the Metrolina region during the same period. Figure 3 shows that decreases in 

motor vehicle NOx appear to coincide with the downward trend in ozone concentrations. 

The size of Mecklenburg County has not prevented a steady trend of improving air 

quality and decreasing motor vehicle emissions. MUMPO believes information provided 

in Figures 1-3 provide strong evidence against NCDAQ’s perception that Mecklenburg 

County mobile NOx emissions need to be managed differently. 

2. Mecklenburg County population, households, and employment are projected 

to become a smaller percentage of the Metrolina totals between 2011 and 

2035.

Although Mecklenburg County dominates the Metrolina region in terms of population, 

VMT, and motor vehicle NOx emissions, its dominance relative to the rest of the region 

is not projected to increase, but rather to decrease slightly. To support this comment, 

MUMPO presents the projected trends in percentage population (figure 4), percentage 

number of households (figure 5) and percentage employment (figure 6), in each 

Metrolina county between 2000 and 2035. These data were used in the Metrolina 

Regional Model (MRM) to generate the VMT and speed data which was in turn used by 

NCDAQ to produce the motor vehicle emissions projections appearing in the draft SIP. 

The VMT and speed data, and ultimately the motor vehicle emissions, are determined by 

population, number of households, and employment. 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 12 

 Appendix C 

November 2, 2011
 Page 4 of 18

The table below shows the absolute (not relative to the region as a whole) percentage 

growth rate for Mecklenburg County during the 2000-2035 period. (Similar data exists 

for the other counties in the Metrolina region.) For each 3-year period in the table, it is 

clear that after 2005, the growth rates of population, households, and employment are 

nearly constant or slightly decreasing. Again, these data are used to generate the 

projected VMT in Mecklenburg County, and thus the motor vehicle emissions projections 

appearing in the draft SIP. 

Mecklenburg County Annual Growth Rate 

2000 to 

2002 

2002 to 

2005 

2005 to 

2008 

2008 to 

2015 

2015 to 

2025 

2025 to 

2035 

Population 2.7% 4.5% 2.3% 1.9% 1.6% 1.2% 

Households 2.8% 6.4% 1.7% 1.8% 1.5% 1.2% 

Employment 2.1% 3.5% 2.0% 2.0% 2.0% 1.6% 

The draft SIP does not suggest a need for a plan to limit the growth of Mecklenburg 

County population or households or employment beyond current projections which 

support the region’s continued attainment of the 1997 ozone NAAQS. . In addition, the 

rate of growth in Mecklenburg County will hold steady or slightly decrease. Therefore 

MUMPO believes neither an explicit nor implicit program to restrict county growth is 

necessary. Mecklenburg County’s size with respect to population, households, and 

employment will not be a deterrent to growth in the rest of the Metrolina region. As a 

result, MUMPO has serious concerns with NCDAQ’s assertion that Mecklenburg County 

motor vehicle emissions need to be managed any differently from the rest of the 

Metrolina region. 

3. NCDAQ’s own data show that motor vehicle emissions in Mecklenburg 

County will decrease from 2011 to at least 2022, in spite of an increase in 

VMT during that same period. 

The combination of State and Federal actions, including those requiring the production of 

lower-polluting motor vehicles, have resulted in cleaner air in the Metrolina area, and are 

expected to result in continued maintenance of the 1997 8-hour ozone NAAQS in this 

region. But in no instance has NCDAQ mentioned a special program to control 

Mecklenburg County motor vehicle emissions, and there is no reference concerning the 

rationale or value of such a special program. 

With input from MUMPO and other partners in this process, NCDAQ developed future 

year emissions inventories for the years 2013, 2016, 2019, and 2022. Without any 

specific plan in the draft SIP to “manage” Mecklenburg County motor vehicle emissions 

differently, NCDAQ still concluded in its Executive Summary for the SIP narrative, 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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November 2, 2011
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“The future year emissions were lower than the 2010 emissions in all cases. ...in 

no future year are the emissions expected to be greater than they were in the 

baseline year.” 

And, below that, 

“The monitoring data clearly shows that the region has attained the 1997 8-hour 

ozone standard, and the maintenance demonstration shows that the future 

emission inventories are expected to be lower than the attainment year inventory 

through the implementation of the various control measures discussed above.” 

MUMPO agrees with these conclusions reached by NCDAQ, and these conclusions are 

clearly supported by factual data contained in the draft SIP submittal. MUMPO adds as 

emphasis that every county in the Metrolina region, including Mecklenburg County, has 

emission inventories in each future year decreasing, according to Table 3-7 and Table 3-

15 in the draft SIP narrative. However, MUMPO is unclear as to how or why NCDAQ 

singles out Mecklenburg County with regards to motor vehicle emissions budgets 

(MVEBs). 

Under the Transportation Conformity rules, transportation plans must be fiscally 

constrained, and it is well established in our approved Long-Range Transportation Plan 

and conformity document that there are no surplus funds for MUMPO to build more 

projects than are currently funded. It is simply not possible to pay for enough new roads, 

and somehow incent enough people to move into or near Mecklenburg County to support 

the idea that Mecklenburg County needs some kind of special management. 

MUMPO perceives that NCDAQ has some concern that with a multi-county MVEB 

Mecklenburg County would somehow grow faster and effectively usurp any MVEB 

surplus in the region. But NCDAQ fails to present any data to support such a notion. 

There is no realistic scenario under which this is possible. In contrast, MUMPO believes 

it has presented three types of data which show Mecklenburg County motor vehicle 

emissions have not and will not increase in the future. 

Based on the data presented above, MUMPO recommends that NCDAQ remove from the 

final version of the SIP narrative and associated appendices, all references to NCDAQ 

recommending Mecklenburg County emissions be managed differently. 

 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
 Page 6 of 18

Comment #2 -- Geographic Distribution of MVEBs 

NCDAQ has provided four options pertaining to the geographic distribution of NOx and 

VOC MVEBs. On the basis of the comments and data provided in Comment #1, 

MUMPO requests that NCDAQ seriously reconsider its position on any separate 

treatment or management of Mecklenburg County motor vehicle emissions. It is clear 

that Mecklenburg County motor vehicle emissions are not now, nor anticipated to be, a 

threat to maintaining the 1997 ozone NAAQS. Since there is no reason for NCDAQ to 

single out Mecklenburg, “Option D” and “Option B” should not be considered for 

inclusion in the final SIP document. 

MUMPO has concluded the most suitable option for the Metrolina region is not any of 

the four options in the draft SIP document. MUMPO does recognize “Option D” to be 

very similar to a choice endorsed by the MPOs, and RPOs and by NCDOT in 2006. At 

that time, the aforementioned parties submitted to NCDAQ a geographic distribution 

which included Cabarrus and Rowan Counties as separate MVEBs, and the remainder of 

the Metrolina with a common MVEB. MUMPO therefore calls on NCDAQ to create an 

“Option E” as illustrated in figure 7, for both 2013 and 2022. “Option E” should be the 

only geographic distribution included in the final version of the SIP document. 

An additional consideration of the Options provided in the draft 

It is a distinct possibility that when the 2010 census data is fully evaluated, new MPO 

boundaries may be created. It is very possible that the southern portion of Iredell County 

could become part of MUMPO. In that event, “Option B” and “Option C” would not 

work. However, MPO boundary changes would be less of an issue if “Option E” was 

chosen. 

 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 15 

 Appendix C 

November 2, 2011
 Page 7 of 18

Comment #3 -- Comments on County-level MVEBs

County-level MVEBs (Option A) should not be applied to the Metrolina region in the 

final version of the SIP. Our reasons are given below. 

MPOs, not counties, responsible for Transportation Conformity 

The establishment of county-level MVEBs, while well-intentioned, marginalizes the 

responsibility of the MPOs in the transportation conformity process. When an MPO is 

larger than a single county, such as the Mecklenburg-Union MPO (MUMPO), the TIP 

and the LRTP are adopted for the entire MPO, and the fiscal constraint condition is met 

MPO-wide. MPOs decide the contents of their TIPs and LRTPs, and are responsible for 

showing that those plans conform to the SIP’s air quality goals by comparing the 

calculated emissions to the MVEB. Counties in North Carolina have no transportation 

planning representative. 

If a county were to have a problem meeting its MVEB, there is no county-level 

organization that could address the problem. The transportation problem would have to 

be addressed by either the MPO or the NCDOT. 

No documentation that county level budgets are critical 

DAQ has given MUMPO the impression that any deviation from the county-level 

MVEBs they prescribe would be detrimental to air quality. However, DAQ has not 

quantified by how much county level MVEBs are a better choice for meeting the ozone 

NAAQS than “Option E” or even “Option C.” NCDAQ has not evaluated the impact of 

a redistribution of the total of MVEBs within the Metrolina area. MUMPO believes that 

without any such technical documentation NCDAQ lacks support for county-level 

MVEBs as necessary to preserve air quality. 

Growth crosses county boundaries. 

Output from the Metrolina Regional Model (MRM) used for our conformity analyses and 

for this draft SIP document show that projected VMT growth is not restricted to the 

county with the increase in jobs or other attractions. County-level projections of jobs or 

other attractions impact growth in VMT through a wide geographic area, and thus 

increase motor vehicle emissions in multiple counties. Therefore, utilizing a multicounty budget would be more consistent with the correct relation between growth and 

emissions. NCDAQ’s county-level MVEBs have the potential to restrict population or 

economic growth in one or more counties, much more readily than would a multi-county 

MVEB. This may not only be unfair, but unnecessary. 

MVEB is a tool for conformity, not a tool for attainment. 

Attainment of the ozone standard is independent of our transportation conformity status. 

Though the MVEB is part of the SIP, and the MVEB will be used for transportation 

conformity, the MVEB are not considered a tool to attaining the air quality standard. 

MUMPO is hopeful that NCDAQ can avoid equating conformity with attainment by 

Public 

attempting to use the MVEB as such a tool. 

Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
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County level MVEBs rare outside of NC 

MUMPO found no other comparable area in the nation that utilizes county-level MVEBs. 

We found that multi-county MVEBs are common practice in EPA Regions 2, 3, 4, 5, 6, 

and 9. Multi-county MVEBs appear to be the norm, generally broken only by state 

boundaries. Multi-county MVEBs are being applied for multi-county, multi-MPO 

maintenance areas and areas across the nation whose nonattainment status ranges from 

marginal to severe. Some examples of areas with multi-county MVEBs are: Dallas-Fort 

Worth; Houston-Galveston-Brazoria; St. Louis MO-IL; NY-NJ-CT; Baltimore; 

Washington DC-MD-VA; Philadelphia-Wilmington-Atlantic City; Clarksville TN - 

Hopkinsville KY; and Atlanta. An exception is the San Joaquin Valley nonattainment 

area, which has 8 county budgets, but each county is also an MPO. MUMPO contends 

that the Metrolina area wants to be – and should be – given the same regional flexibility 

to manage its transportation planning decisions that pertain to conformity. 

 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
 Page 9 of 18

Comment #4 -- Safety Margins

NCDAQ’s analysis shows Metrolina NOx and VOC emissions decreasing from 2010 to 

2022. As a result, their respective safety margins increase over the same period. The 

NCDAQ says it decided to allocate up to 50% of the safety margin to the MVEB. 

However, the total allocation added to the 2013 amounted to only 26% of the total NOx 

safety margin available and 27% of the total VOC safety margin available. Furthermore, 

the total allocation added to the 2022 MVEBs amounted to only 14% of the total NOx 

safety margin available and 17% of the total VOC safety margin available. While 

MUMPO is hopeful that none of the safety margin is ever needed in the Metrolina region, 

NCDAQ has plenty more safety margin it could set aside for MVEBs and still be well 

below the 50% limit. 

The NCDAQ has developed and implemented a five-step approach for determining a 

factor to use to calculate the amount of safety margin to add to what is effectively the 

baseline MVEB. Having evaluated DAQ’s procedure for calculating safety margins 

available for the baseline MVEBs, MUMPO makes the following comments: 

The percentages chosen for steps 1-4 are arbitrary. 

NCDAQ’s procedure is serviceable without needing to be technically justified. A range 

of different percentages or criteria could have been used, and be equally serviceable. 

Mecklenburg County was given no added safety margin for unexpected rapid 

growth (step 3) because it is already the largest county in the region. 

MUMPO sees this as another example of singling out Mecklenburg County to be 

managed differently. Earlier in our comments we provided data and commentary as to 

why this singling out is unnecessary. MUMPO applies those same comments along with 

figure 1 through figure 6. Furthermore, NCDAQ’s treatment of an “emissions 

dominant” county appears to be inconsistent with how NCDAQ treated Wake County in 

the Triangle Region’s 2007 ozone maintenance SIP. The process NCDAQ used to 

allocate a “safety margin” to the MVEBs in the Triangle Region1

 is very similar to the 

process NCDAQ employed for the Metrolina Region. Wake County was estimated to 

emit 45% of all the on-road mobile NOx in the Triangle Region for the 2008 MVEB. 

NCDAQ wrote the following in awarding safety margins: 

“Step 2 Account for continued rapid growth and provide flexibility for counties that are 

small contributors to on-road mobile NOx emissions inventory 

 

“Chatham, Granville and Person get 10% additional safety margin in 2008 

 

“Durham, Franklin, Johnston, Orange and Wake get 5% additional safety margin in 

2008 

 

 

1

 Source: Mobile Source Inventory Raleigh-Durham-Chapel Hill, NC 8-Hour Ozone Redesignation 

Demonstration and Maintenance Plan June 7, 2007 Appendix C.3, page 4-40 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
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“Additional safety margin increases of 5-10% are applied to all counties. This is simply 

to account for continued rapid growth in the Triangle area.” 

Compare that to Mecklenburg County, which was estimated to emit 49% of all the onroad mobile NOx in the Metrolina Region for the 2013 MVEB, yet received 0% safety 

margin credit. MUMPO hopes that NCDAQ does not see Mecklenburg County’s 49% as 

more significant than Wake County’s 45% in this case. Also, because surrounding 

counties, but not Mecklenburg, would get added safety margin for unexpected growth, it 

could be viewed as DAQ promoting sprawl. Therefore, MUMPO requests NCDAQ add 

at an additional 8% (the minimum for step 3) of Mecklenburg County’s emissions to be 

allocated to the 2013 MVEBs. 

The sum of the safety margins provided in table 4-1 in the narrative and table 4.4.2-1 in 

Appendix B.3 should add up to either 15% or 17% (instead of 10% or 12%) in the 2013 

column. The allocation for step 2 (5%) may not have been applied. If so, then the safety 

margins allocated in 2022 for those counties should also be increased to either 25% or 

27%. 

DAQ is unclear as to whether a larger fraction of the safety margin initially 

assumed for a specific reason -- and yet still within the allotted safety margin -- 

would be provided if needed. For example, if the unanticipated input model data 

changes (step 2) turned out to be 6% instead of 5%, would DAQ allow use of 6% of the 

total (perhaps 15%) safety margin, or only 5%? MUMPO believes that the amount of 

safety margin used for a given area should be limited by that area’s need, and not by what 

was initially assumed in the draft SIP for a specific reason (step 1 or 2 or 3 or 4). 

Concluding request. 

MUMPO requests that NCDAQ choose a modified version of “Option D,” which 

MUMPO has depicted in Figure 7 as “Option E” for the geographic distribution of 

MVEBs. “Option E” is identical to the geographic distribution agreed upon in writing by 

the MPOs, RPOs, and NCDOT in 2006. Mecklenburg County should be treated in a 

manner consistent with that of the rest of the Metrolina region with regard to MVEB and 

safety margin. 

“Option C,” while not singling out Mecklenburg County for special treatment, is flawed 

because it did not consider the possibility that Iredell County may become a part of 

MUMPO. 

NCDAQ should not apply county-level MVEBs to the Metrolina region. 

 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 19 

 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
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Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 21 

 Appendix C 

November 2, 2011
Page 13 of 18

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 22 

 Appendix C 

November 2, 2011
Page 14 of 18

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 23 

 Appendix C 

November 2, 2011
Page 15 of 18

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
Page 16 of 18

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
Page 17 of 18

Figure 7. 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
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Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 27 

 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

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 Appendix C 

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Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

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Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

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Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

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 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
Attachment 

November 2, 2011 

Page 1 

Attachment: Response to General Comments provided by the United States 

Environmental Protection Agency (USEPA) 

The following are general comments that the USEPA feels would strengthen North Carolina’s 

redesignation request and maintenance plan for the Charlotte-Gastonia-Rock Hill, North 

Carolina-South Carolina 1997 8-hour ozone nonattainment area. 

1. Page 2-7, Section 2.3 – For clarity and completeness, please add the pollutants that are 

reduced as a result of the local programs listed in this section. 

Response: The pollutants that are reduced as a result of the local program’s measures listed in 

Section 2.3 were added. 

2. Page 3-12, Section 3.3.2 - There is no discussion whether or not the 2010 emissions 

inventory represents actual point source emissions as required for a redesignation. From 

Appendix B.1, it appears that the 2009 actual point source emissions were projected to 

2010 for the base year inventories. The point source inventory for the 2010 baseline 

inventory should represent actual emissions for 2010. Please clarify that the 2010 point 

source emissions in the redesignation meet this requirement and that actual 2010 

emissions were used where available, particularly for significant point sources. 

Response: The actual 2010 point source emissions inventory will not be available until 

December 2011. However, for the facilities that report to the USEPA’s Clean Air Markets 

Division (CAMD), significant point sources for nitrogen oxides (NOx) emissions, the North 

Carolina Division of Air Quality (NCDAQ) used the actual 2010 data from the CAMD database. 

For the remaining major sources, the latest available data from 2009 was used and grown to 2010 

using the USEPA’s EGAS (Economic Growth Analysis System) growth projection model. The 

NCDAQ believes this inventory used for the maintenance plan is representative of 2010 

emissions. 

3. Page 2-8, Table 2-5 – The table presents emissions from EGUs [Electric Generating 

Units] in and near the nonattainment area for the 2nd and 3rd quarters of 2002-2010. The 

submittal makes the assertion that the 50 percent reduction in NOx emissions since 2002 

from these facilities are permanent and enforceable. However, emissions for 2010 were 

nearly 23% higher than 2009. A list of controls installed, dates of installation, and 

expected reductions would strengthen the argument. It would be more accurate to change 

the wording of the last sentence of the first paragraph on page 2-8 to indicate that the 

NOx SIP [State Implementation Plan] call reductions are permanent and enforceable. 

Response: The last sentence has been changed to read “The NOx SIP Call emission reductions 

are permanent and enforceable.” 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 34 

 Appendix C 

November 2, 2011
Attachment 

November 2, 2011 

Page 2 

4. Page 3-2, Section 3.2 - It states that “Each component of the State’s foundation control 

program is essential in demonstrating maintenance of the air quality standards.” And then 

goes on to list the federal and state measures that are included in the foundation control 

program. The state measures listed include, among others, the I/M [Inspection and 

Maintenance] program, the Clean Smokestacks Act, heavy duty diesel engine gap filling 

requirements and an open burning regulation. 

a. The Clean Smokestacks Act was submitted to EPA for approval into the federally 

approved SIP and the proposed rule notice was published on June 22, 2011 (76 

FR 36468). 

b. A note should be added to the narrative to indicate that the I/M program and open 

burning regulations have been submitted for federal approval. 

Response: The following language was added to the three programs listed in comment 4a and 

4b. 

Clean Smokestacks Act: This State law was submitted to the USEPA for adoption into 

the SIP in August 2009, however, the USEPA has not yet approved it into the SIP. These 

emission reductions are currently state enforceable, however, once the USEPA has 

federally approved the law into the SIP, these emission reductions will be federally 

enforceable as well. 

I/M rule: The rule for the I/M program was submitted to the USEPA for adoption into the 

SIP in August 2002 and was federally approved in October 2002. Therefore, these 

emission reductions are both state and federally enforceable. 

Open burning rule: The open burning rule was submitted to the USEPA for adoption into 

the SIP in March 2006, however, the USEPA has not yet approved the adoption of this 

rule into the SIP. These emission reductions are currently state enforceable, however, 

once the USEPA has federally approved the rule into the SIP, these emission reductions 

will be federally enforceable as well. 

5. Page 4-2, Section 4.3 – Of the four motor vehicle emissions budget (MVEBs) options 

presented in the prehearing, EPA prefers option A which sets separate budgets for each 

county. If Option B or D is ultimately chosen, it should be clarified that the additional 

Mecklenburg County budgets are sub-budgets of the overall MPO/RPO budget which 

also includes Mecklenburg County. Currently, it could appear that the additional 

Mecklenburg budget is a separate budget. The final redesignation submittal should 

indicate how public comments were used to make the option selection. 

Response: The NCDAQ appreciates the USEPA comments regarding the establishment of 

MVEBs. The NCDAQ will take this comment into consideration along with the other comments 

received by transportation partners. The final documentation will outline the comments received 

and how these comments were used to make the final option selection. 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 35 

 Appendix C 

November 2, 2011
Attachment 

November 2, 2011 

Page 3 

6. Please include the conversion factor or process used to convert between tons per day and 

kg [kilograms] per day when calculating MVEBs. EPA cannot make this interpretation 

for the State. 

Response: The following language has been added to Appendix B.3 On-road Mobile Source 

Documentation: 

The MOVES model reports emissions out several decimal places and for this plan the 

emissions have been rounded to the second decimal place. The conversion to kilograms 

used the actual emissions reported in the MOVES model. The conversion was done 

utilizing the “CONVERT” function in an EXCEL spreadsheet. 

Other Comments – Comments such as typographical or editorial errors and may also include 

suggestions for clarification. 

7. Page 3-1 - It states that “...NCDAQ has implemented programs that will remain 

enforceable...” and goes on to say “Sources are prohibited from reducing emission controls 

(anti-backsliding) following the redesignation of the area unless such a change is first approved 

by the USEPA as a revision to the NC SIP that is consistent with Section 110(l) of the CAA.” 

But this section does not specify what those controls are. So, it appears that even state only 

approved measures will fall into this category when in fact they won’t. 

Response: The above mentioned paragraph was changed as follows: 

 The NCDAQ has implemented programs and submitted rules and laws to be adopted into 

the SIP. Once these rules and laws have been approved into the SIP by the USEPA, these 

programs will remain enforceable and are hereby submitted as the plan to ensure that 

maintenance of the 1997 8-hour ozone standard will continue. Sources are prohibited 

from reducing emission controls (anti-backsliding), for controls due to rules or laws that 

have been submitted to the USEPA for adoption into the SIP, following the redesignation 

of the area unless such a change is first approved by the USEPA as a revision to the 

North Carolina SIP that is consistent with Section 110(l) of the Clean Air Act. 

8. Appendix B clearly states that the emissions inventories were calculated on a ton per 

summer day basis. NC should consider making this distinction in the narrative as well. 

Response: Language has been added to Section 3 of the narrative that makes the distinction that 

the emissions inventory is for a summer day. 

Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

 36 

 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

Redesignation Demonstration and Maintenance Plan 

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 Appendix C 

November 2, 2011
Public Notice Report, Comments Received and Responses 

Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area 

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 Appendix C 

November 2, 2011