UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460

The Honorable Lisa Bonnett Director fllinois Environmental Protection Agency I 021 North Grand Avenue Eas t P.O. Box 19276 Springfield, Illinois 62794-9276
Dear Ms. Bonnett: 

## MAR 2 02015
OFFICE OF AIR AND RADIATION

I am writing to update yo u on the status ofthe U.S. Environmental Protection Agency's progress in implementing the primary National Ambient Air Quality Standard (NAAQS) for sulfur dioxide (S02) set in 2010 at 75 parts per billion (ppb) as a 1-hour average. In July 2013, the EPA identified areas in 16 states as nonattainment and expressed the intent to address designations for the remainder of the country in separate future actions.
On March 2, 2015 , the U.S. District Court for the Northern District of Californi a accepted as an enforceable order an agreement between the EPA and Sierra Club and Natural Resources Defense Counci l to resolve litigation concerning the deadline for completing the designations. The court's order directs the EPA to complete designations in three additional rounds: the first round by July 2, 20 16, the seco nd round by Decemb er 31, 2017, and the final round by December 3 1, 2020. The EPA will complete these designations by designating areas as either nonattainment, unclassifiab le/attainment, or un c lassi tiable.
In the first round of designations, the EPA will designate two groups of areas: I) areas that have newly monjtored vio lation s of the 2010 S02 standard , and 2) areas that contain any stationary source that according to the EPA 's Air Markets Database either emitted more than 16 ,000 tons ofS02 in 2012 or emitted more than 2,600 tons of S02 and had an emission rate of at least 0.45 lb s S02 /mmbtu in 2012 and that has not been announced (as ofMarch 2, 2015) for retirement. In the enclosure to this letter, the EPA provides the schedule we intend to fo ll ow to meet the July 2, 2016 , dead li ne. The EPA has identified the following electric power plant sources in your stat e as meeting the criteria established in the court's order:

Internet Address (UAL) • http://www.epa

.gov Recycled/Recyclable • Printed w ith Vegetable Oil Based Inks on 1 00% Postconsumer, Process Chlori ne Free Recycled Paper2012 so2 2012 so 2 S tat e County Facili t y N ame Emissions Em i ssio ns Rate (tons) (lb / mm b tu) 1L P utnam Hennepin P ower S t at i on 5,906 0 . 501 IL J a s per Newton Power Station 16 , 5 1 9 0.590 IL Mas sac Joppa Steam Coal P owe r Plant 16 ,991 0.475 IL Williamson Marion P ower Station 5,850 0.489 IL Madison Wood Ri ve r Pow er Sta t ion 6 , 756 0.476

The E PA will use the m os t rec e nt avai l able i nf o rmation when maki n g de sig n at io n and bounda r y d ec i s ions for t h e i ndicat e d are as. I f you wo ul d lik e to submit updated recomm e ndat i ons a nd sup p o r tin g informat i on fo r the EPA to consider for the affected a r eas in your state , we r eq uest th at you d o so by Se pt e mber 18 , 2015.

f n addi ti on, the EPA h as identified the following e l ect ri c power plant sou rc es in the neighboring sta t es of Indiana and I owa th at also meet the c r iteria established in the com1 ' s order , and m ay poten tially be impacting yo ur state : 2012 so2 2012 so 2 S tate County Facility Name Em i ss i on s Em i ssions R a t e (to n s) (lb / m mbtu) I N Gibson G ib son Generating S t at i o n 22 , 447 0 . 249 I A De s Moines Burlington Gen e r at in g S t a tion 4 ,697 0 . 672 You may wis h t o discuss th e designation fo r these areas w ith repre sentat i ves o f Indiana and Iow a, and provide your own designation recommendation for th e potentially af fecte d areas in your state. Again,

please provide any inf o rmation you would like u s t o consider by Septemb e r 18 , 2015. Th e EPA has u p d ated it s March 24,2 0 1 1 , desig n ation guidance f or the 20 1 0 S02 s t an d ar d t o s u ppor t analysis of des i g n ation s a nd bo u ndaries for t h ese n ext rou nd s of des i gnation s . The updated guidance can be found on the E PA 's website at http :// epa. g ov / airqua/ity/sul(urdioxide / guidance.ht ml. The E PA h as

a l so provided two technical assis tance docum ents that provide advice on the use of modeling and monitoring data when det e rmining if an area i s meeting or no t meetin g the 20 1 0 S 0 2 s tandard. Th ese docume nt s can be found on th e E PA ' s website a t hllp :l/ epa. go v l airqua/it y/s ul[urdioxide / implement.html. The court's order direct s the E PA to complet e the seco nd round of are a d esig n at i ons by December 3 1 ,

20 17. These designa t ion s would address area s wher e sta tes have not instal l e d and begun operating a n e w

S 0 2 mon it ori n g ne t work m ee t ing t h e EPA 's specifications re f e r enced i n o u r p r oposed r u l e t i t l ed, " Data R e quir e ments Rul e for the 1- h our S0 2 primary NAAQS". This rule , which w as proposed in the Federal R e giste r on May 13 , 2014 , would direct state and trib al air agencies to pr ov id e data to characterize c urr e nt a ir quality in ar e as w ith l a rge sources of S0 2 if s uch areas do n ot have s u f ficient air quality m o nitoring in place t o id e ntify maximum S0 2 conc e ntrations. The data collected as a r es ult of thi s p r o p osed rule would be u s ed in the designations process. Lastly , the court ' s order directs the E PA to d es ignate all remainin g areas by D ece mber 3 1 , 2020. The E PA w ill pr ovide sta te s with additional i nformat i on on the de sig n at ion s process associated with these la t e r deadlin es a t a later date.We look forward to co ntinued dialogue with yo u and yo ur staff as we work together to implement the 

### 20 I

### 0 S02 standard and achieve its intended pub li c health protection. For additional information regarding designation s fo r the 

### 20 1 0 S02 standard , please visit our website at 

### www.epa.gov/so2des ignations. Should you have any questions, please do not hes itate to call me or Scott Mathi as of my staff at 

### 91 9-5 41-5310 and 

### rnathias

. scott@ epa.gov
. S incerely ,

Janet G. McCabe Acting Assistant Administrator
Enc losure

cc : Susan Hedman EPA Region 5 Admini strato r

### ENCLOSURE
TIMELINE FOR 20 10 PRIMARY S02 NAAQS DES IGNATION PROCESS FOR AREAS ASSOCIATED WITH JULY 2 , 2016, COURT

- ORDERED DEADLINE* Milestone Date** Court Order March 2, 2015 States may submit updated recommendations No later than September 18 , 2015 and supporting information for area designations to the EPA The EPA notifies states concerning any o/a January 22 ,2016 , but absolutely no later intended modifications to their than 120 days prior to final designations, i.e., recommendations ( 120-day letters) March 2, 20 16 The EPA publi shes public notice of state o/a February 3 , 2016 recommendations and the EPA's intended modifications and initiates 30-day public comment period End of30

-day public comment period o/a March 4 , 2016 States provide additional information to o/a April 8 , 2016 demonstrate why an EPA modification is inappropriate The EPA promulgates final S02 area No later than July 2, 2016 designations (no later than 16 months from Court Order)

.. 

### * The court ' s order directs the EPA to promulgate addttiOnal rounds of destgnatiOns by December 31 , 20 17 , and by December 31 , 2020. 

## ** o/a 

### = on or about