Mr. Ron Curry Regional Administrator STATE OF ARKANSAS
AsA HUTCHINSON GOVERNOR September 11, 2015

U.S. -Environmental Protection Agency, Region VI 1445 Ross Avenue, Suite 1200 Dallas, Texas 75202-2733

Re: Update to Sulfur Dioxide (S02) National Ambient Air Quality Standard (NAAQS) Area Attainment Designation Recommendation for Counties in the State of Arkansas.

Dear Mr. Curry:

Section 107(d)(l) ofthe Federal Clean Air Act requires state governors to recommend attainment status designations within one year ofthe promulgation ofany new or revised NAAQS. On June 2, 2010, the federal Environmental Protection Agency (EPA) promulgated a new primary 1-hour NAAQS for S02 at 75 ppb for the 3-year average ofthe 99th percentiles ofthe maximum daily values per calendar year. The existing secondary standard of0.5 ppm per 3-hour period remained unchanged.

As perthe State's letter dated March 22, 2011, all monitored counties in Arkansas
are currently attaining the existing primary and secondary S02 standards. However, as part ofthe implementation ofthe new 1-hour NAAQS, EPA has begun requiring, in addition to monitoring data, the use ofdispersion modeling for areas with facilities emitting large quantities ofS02 as a means ofdetermining compliance with the new standard. Currently, only two counties inArkansas fall under this requirement: Independence and Jefferson. These counties are subjectto this requirementbecause two facilities operatedby EntergyArkansas, Inc. have sulfur dioxide emissions that are greater than the level thatthe EPA determined would require review.

Based on the analysis ofmodeling that was conductedby Environmental Resources Management (ERM) for EntergyArkansas, Inc. and provided to the Arkansas Department ofEnvironmental Quality for review, both Independence and Jefferson counties will comply with the standard. Copies ofERM's analysis reports, 

### S02Air Dispersion Modeling Report for White Bluff Steam Electric Station and

### S02Air

500 WOODLANE STREET • LITTLE ROCK, AR 72201
TELEPHONE (501) 682-2345

www

.governor

.arkansas.gov

### Dispersion Modeling Report for Independence Steam Electric Station, are enclosed for your review.

Consistent with the previous recommendation, it is the State's recommendation thatthe two counties with existing monitor sites, Pulaski and Union shouldbe designated "attainment". Based on the information contained in the enclosed reports, Independence and Jefferson counties shouldbe designated "unclassifiable/attainment". All other counties inArkansas shouldbe designated "unclassifiable."

The attachedtable lists all Arkansas counties and their recommended designations. For further information regarding these recommendations, please contact Stuart Spencer, Chiefofthe Air Division, Arkansas Department ofEnvironmental Quality, by phone at 501-682-0750 or email at SPENCER@adeq.state.ar.us.

attachment: Table ofArkansas County Designation Recommendations

enclosures:

S02 Air Dispersion Modeling Report for Independence Steam Electric Station S02 Air Dispersion Modeling Report for White BluffSteam Electric Station

500 WOODI.ANE STREET • LITTLE ROCK, AR 7220 I
TELEPHONE (501 ) 682-2345 www.governor.arkansas.govArkansas 1-Hour Sulfur Dioxide (S02) Designation Recon1mendations
County Reco1nmended Designation Arkansas Ashley Baxter Benton Boone Bradlev Calhoun Carroll Chicot Clark Clav Cleburne Cleveland Columbia Conway Craighead Crm.vford Crittenden Cross Dallas Desha Drew Faulkner Franklin Fulton Garland Grant Greene Hempstead Hot Spring Howard Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable

500 Woom,/u"lE STREET • Lrn'LE ROCK, AR 7220 I
TELEPHONE (501) 632-234-5 www.govcr1101:arkansas.govArkansas 1-Hour Sulfur Dioxide (S02) Designation Recommendations (cont.)
County Recommended Designation Independence Izard Jackson Jefferson Johnson Lafayette Lawrence Lee Lincoln Little River Logan Lonoke Madison Marion Miller Mississippi Monroe Montgomery Nevada Nevvton Ouachita Perry Phillips Pike Poinsett Polk Pope Prairie Pulaski Randolph St. Francis Saline Scott Searcy Unclassifiable/Attainment Unclassifiable Unclassifiable Unclassifiable/Attainment Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable Attainment Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable

500 WOODL.ANE STREET • LnTLE ROCK, AR 72201
TELEPHONE (501) 682-23,15 www.governor.arkansas.govArkansas 1-Hour Sulfur Dioxide (S02) Designation Recommendations (cont.)
County Recommended Designation Sebastian Sevier Sharp Stone Union Van Buren Washington White Woodruff Yell Unclassifiable Unclassifiable Unclassifiable Unclassifiable Attainment Unclassifiable Unclassifiable Unclassifiable Unclassifiable Unclassifiable

500 WoomANE STREET • LrrnE RocK, AR 72201
TELEPHONE (50 I) 682-2345 \vww.govcrno1:arkansas.gov