UNIT E D STATES ENVIRONMENTAL PROTECTION AGENCY REGIO N 6 .The H onorable

J ohn Bel E dwards Governor of Louisiana Post O ffice Box 9 4004 Baton Rouge

,Louisiana 70804 Dear Go vernor Edwards

: 14 4 5 R OSS AVE N U E ,S UI T E 1200 DALLAS

,TEXAS 75202

-2733 Fe b ruary 11,2016 Office of the Reg

i ona

l Adm

i n i st r ator Thank youfor your sta ffs recommendations dated September 18
,20 1 5, onair quali ty designations for the st ate of Louis

i anafor the 201 0 revi sion to the primary Nat iona
l Ambi ent Air Quality Standard (NAAQS) for sulfur dioxid e (S02). Reducing

l evels of S02 pollut

i onis an important part of the U.S. E nvi ronme ntal Protection Agency's commitment
to acle a n,he althy environment. Ex posure to S02 can causea range of adverse health effects, inclu d i ng narrowing of the airways which can cause difficulty breat hi ngand in creased asthma symptoms. This letter

i sto notify youof the EPA's preliminary intent

i ons regard

i ng your recommended designations. On June 3, 2010,

t he EPA strengthened the health-based
or "pr im ary" standard for S02 by establishing

a standard for 1-hour average S02 concentrations

at a level of 75 parts per billion. Within one year after a newor revised standa
rd is established, the Clean Air Act requires the Governor of each state to submit to the EPA alist of all areasin the state, with reco mmendations for whe ther each area meets the standard. Throug h an interactive process, the EPA cons
i ders the recommendations and then promulgates designations for all areas across the country. On July 25 ,2013

,the EPA d esigna ted 29 areasin 16 states as nonattainment

,but did not at that time desi gnate other areas. Pursuant to a March 2, 2015, courtordered schedule,

1 the EPA must complete

t he remaining S02 de signa tions by thre e specific deadline s: July 2, 2016, December 31
,2017, and December 31,2020. This current round of de s ignations , t ob ecom pl eted b yJu l y2 ,20 1 6 ,addresses two groups of areas: (1) areas

t hat have new
l y mo nitored vi ol ations of t he 20 10 S02 NAAQS based onthe most recent three calen da r years of certified monitored ambien

t air quality data, and (2) areas that contai n any stationary source that had not been announced asof March
2 ,2015, for retirement and tha t accord

i ngto the EPA's Air Markets Database emit ted in 2012 either (i ) more than 16,000 tons of S02 or (ii) more than 2,600 tons of S02 with an annua

l average

e mission rate of at l east 0.45 pounds of SO :J mmBTU. After carefully considering

L o uisiana

' s recommendations and othe r available technical information, the EPA intends to designate

as nonattainment the fo ll owing area: 1 Sierra Club v.A !c Cart hy ,N o.3- 1 3-c v-3953

( SI ) (N.D. Ca l. Mar. 2, 2015). Th

i s paper is printed wit h vege

t able
-oil-based

I nks and

i s 100-percent pos t consumer recycled mater

i a l , ch

l orine-free-processed and recyclableIn t end e d Nonattainment Area D e sot o Parish, Lou
i siana (part
) * Int e nded Nonattainment Counties De So to Parish (p) (p) i ndicates portion
o f county The asterisk(*)

i n d ic a tes the designation and boundary for this in t ended nona tt ainment area repre
s ents a modification to the designation and boundary

t hat you have recommended

. Because the EP)\ has
i n su fficient information

t o de t ermin e whether the follow

i ng area is mee
t ing or n o t meeting the S02 NAAQ S, the EPA intends to designate this area as unclassifiable: I n t ended Unclassifiable Area C al cas i eu Parish, Louisiana* Intende d Unclassifia bl e C ounties Ca l casieu Parish The asterisk(*)

i n dicates the designation for this intend
e d unclassifiab

l e area repre
s ents a mod
i fication to the designation that you have recommended. The enclosed Technical Support Document provides

a detailed analysis that supports our intended designation decis

i ons. If your state has additional information that the EPA should conside

r prior to finalizing th ese d e signations, please subm

i t it to us by Apri
l 19,20

1 6 . We a l so wi ll be pub li shing a notice in the Fed e ral Register announcing

a 30-day period for the public to provide

i nput on the EPA's i ntended designa ti on decisions. We will promulgate the designations for these a r eas by July 2, 2016. We will designate all o ther previously undesignated areas in the state on a schedule con si stent with the prescribed timing of the court order, i.e., by December

3 1, 2017, or Decemb

e r 31 , 2020. We look forward

t o a continued dialogue with you and y o ur staff as we work together to complete the area designations and impl emen

t the 201 0 primary S0 2 s t andard. For add it i o na l informa

t ion regarding designations under the S02
s t andard, please visit our website at www.epa.gov/so2designations. Should you have any quest

i ons, p l ease do not hesitate to call me, or have your staff contact Mr. G u y Dona

l dson of my staff at (21 4 ) 665-7242, or via email at Donaldson.guy@epa.gov.

· Enclosure cc: Chuck Car B r own, Ph.D. Secretary,
L ou i siana Department of Envi r onmental Quality Ms. Tegan T r ea d away Louisiana De p artment
o f Environmental Quality