### Beverly Eaves Perdue Governor
Gwendolyn Keyes Fleming Regional Administrator USEPA, Region 4 SamNunn Federal Center 61 Forsyth Street, SW Atlanta, Georgia 30303-8960 DearMs. Fleming: Director August 2, 2012 Dee Freeman Secretary

I ampleased to submit the Carbon Monoxide (CO) Limited Maintenance Plan for the Charlotte, Raleigh/Durham and Winston

-Salem CO maintenance areas. The North Carolina Division ofAir Quality (NCDAQ) relied on the United States Environmental Protection Agency's (USEPA's) October 6, 1995 memorandum, "Limited Maintenance Plan Option for Nonclassifiable CO Nonattainment Areas" to develop this CO Limited Maintenance Plan. Enclosed is one hard copy ofthe complete package containing the limited maintenance plan, the supporting documentation on how the emission estimates were developed and an exact duplicate electronic copy on compact disk
. Additionally, the disk includes the MOVES model input and output files
. The NCDAQ is exercising the limited maintenance plan option since the CO maintenance areas are well below the CO National Ambient Air Quality Standard (NAAQS). In a limited maintenance plan, maintenance is demonstrated when the monitoring data for the CO maintenance areas are meeting the air quality criteria, which is 85% ofthe CO NAAQS
. The CO Limited Maintenance Plan submittal contains the other elements necessary for a limited maintenance plan including an emissions inventory for a typical winter day for the 2010 attainment year, a commitment to continue operation ofthe air monitoring network to verify the attainment status over the attainment period and contingency measures to ensure prompt action is taken to correct any violation ofthe CO NAAQS
. Thus, the CO limited maintenance plan fulfills the requirements ofSection 175A ofthe Clean Air Act as amended. The NCDAQ issued a public notice announcement on June 29, 2012 indicating that the CO Limited Maintenance Plan documentation was available for public comment and posted on the NCDAQ website for review
. The public notice announcement was sent to a number ofdistribution lists managed by the NCDAQ. These distribution lists included numerous stakeholders from industry, environmental groups, and transportation partners. The NCDAQ believed that sending the public notice announcement to these groups was more effective than publishing the notices in a few local newspapers and is consistent with the requirements described in the April6, 2011 , memorandum, "Regional Consistency for the Administrative Requirements ofState Implementation Plan Submittals and the Use ofLetter Notices." Additionally, the NCDAQ

1641 Mail Service Center, Raleigh , North Carolina 27699-1641 217 West Jones Street, Raleigh ,NC 27603 Phone: 919-707-8401 I FAX 919-715-0718 I Internet: www.ncair
.org An Equal Opportunity/ Affirmative Action Employer

# N~rthCarolina 

# )VaturalllfMs. Fleming August 2, 2012 Page2 website has Rich Site Summary (RSS) feed which regularly delivers changes to the website content to those that have signed up for it. The public notice announcement also indicated thatthe public may request a public hearing. The NCDAQ did not receive any public comments or requests for a public hearing. The commentperiod opened onJune 29, 2012 and closed on July 31, 2012. Ifyou have any questions regarding this submittal, please contact Laura Boothe ofmy staff at (919) 707-8721 or laura.boothe@ndenr.gov.

SCH:pdj Attachment
cc SushmaMasemore, NCDAQ Scott R. Davis, USEPA Lynorae Benjamin, USEPA Sincerely,

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# 0:**~** ..9r Sheila C. Holman

William Barnette, Forsyth County Office ofEnvironmental Assistance and Protection Donald Willard, Mecklenburg County Air Quality