UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 4

The Honorable Nikki Haley Governor, State ofSouth Carolina P.O. Box 12267 Columbia, South Carolina 29211 Dear Governor Haley: ATLANTA FEDERAL CENTER 61 FORSYTH STREET ATLANTA, GEORGIA 30303-8960 

### FEB
- 6 2013

Thank you for your recommendations dated June 2, 2011, and updated onJanuary 12, 2012, on air quality designations for the State ofSouth Carolina for the 2010 revision to the primary National Ambient Air Quality Standard for sulfur dioxide (S{h). Reducing levels ofS{h pollution is an important part ofthe U.S. Environmental Protection Agency's commitment to a clean, healthy environment. Exposure to S02 can cause a range ofadversehealth effects, including narrowing ofthe airways which can cause difficultybreathing and increased asthma symptoms. This letter is to notify you ofthe EPA's preliminaryintentions regarding your recommended designations. On June 3, 2010, the EPA strengthened the health-based or "primary'' standard for S<h by establishing a standard for 1-hour average S02 concentrations at a level of75 parts perbillion. The Clean AirAct requires the EPA to complete the initial designations process within two years ofpromulgating a new or revised standard. Ifthe Administratorhas insufficient information to make these designations, the EPA has the authority to extend the designation process byup to one year. On July 27, 2012, the EPA announced that it had insufficient information to complete the designations for the 1-hour so2standard within two years and extended the designations deadline to June 3, 2013

. At this time, the EPA is proceeding with designating as nonattainment most areas in locations where existingmonitoring data from 2009-2011 indicate violations ofthe 1-hour S02 standard. The EPA intends to address the designations for all other areas in separate future actions. With input from a diverse group ofstakeholders, the EPA has developed a comprehensive implementation strategy for these future actions that focuses resources onidentifying and addressing unhealthy levels ofS02. The strategy is available at: http://www.epa.gov/airquality/sulfurdioxide/implement.html. The EPA will continue to work closely with you and our other partners at the state, tribal and local levels to ensure health-protective, commonsense implementation ofthe 1-hour S{h standard

. The EPA'sreview ofthe most recent monitored air quality data from 2009-2011 shows no violations of the 2010 S02standard in any areas in South Carolina. Consequently, the EPA is not yet prepared to propose designation action in South Carolina and is therefore currently deferring action to designate areas in South Carolina. The EPA expects to be able to proceed with designation action in South Carolinaonce additional data are gathered pursuant to ourcomprehensive implementation strategy. In a separate future action or actions the EPA will notify you ofourintended designations for these areas,

Internet Address (URL) • http://www.epa.gov Recycled/Recyclable • Printed wtth Vegetable 00 Based Inks on Recycled Paper (Minimum 30% Postconsumer)and seekpublic comment onthese actions, no later than 120 days priorto promulgating any final designations. We look forward to a continued dialogue with you and your staffas we work togetherto implement the 2010 primary S02 standard. Foradditional informationregarding initial designations on the S02 standard, please visit our website at www.epa.gov/so2designations. Should youhave any questions, please do nothesitate to call me at 404-562-8357 orBeverly Banister ofmy staffat 404-562-9326.

cc: CatherineTempleton Sincerely,

# ~~h Gwendolyn

# J: ;;;;r:,;**~**(J Regional Administrator

Commissioner, South Carolina Department

ofHealth and Environmental Control (SC DHEC) Myra Reece Chief, Bureau ofAir Quality Control, SC DHEC Gina McCarthy, Assistant Administrator for Air and Radiation Stephen D. Page, Director, Office ofAir QualityPlanning and Standards