Yellowstone County Commission a

Treasure State Resource Industry Asso

Petition for Reconsideration of EP

SO2 Designation for a Portion o

Yellowstone County

(Yellowstone SO2 Designation)
Yellowstone County presents a u

case that should not have be

designated nonattainment

EPA should:1. reconsider and repeal the Yellowstone SO2

Designation based on new data that further

demonstrate that no portion of Yellowstone 

should have been designated nonattainmen

2010 SO2 NAAQS; and

2. stay the Yellowstone SO2 Designation pendi

completion of EPA’s administrative proceed
Yellowstone County should not 

been designated nonattainment 

on CAA statutory requiremen

– CAA §§ 107(d)(1)(A) and (B)(iii) and 107(d

require the Administrator to base designat

the following factors:
1. The state’s initial designation, wh

“unclassifiable” for Yellowstone C

– The State of Montana (State) submitted an initial designati

determination of “unclassifiable” for Yellowstone County o

2011 based on its conclusion that 2010 emissions alone did 

a nonattainment designation.

– The State reaffirmed its determination that Yellowstone Co

be designated “unclassifiable” and disputed EPA’s proposed

modification of the State’s initial designation on April 3, 20

– State representatives including the Governor, U.S. Congress

County Commissioners, and the Mayor of Billings all suppo

unclassifiable designation with letters of support and discu

EPA.

– The State only provided a five‐factor analysis for a smaller

nonattainment area in Yellowstone County as a fallback in 

again rejected the State’s “unclassifiable” designation.

– EPA’s final Yellowstone SO2 Designation went against the St

sustained assertion that all of Yellowstone County should b

designated “unclassifiable.”
2. Air quality data, all of which

demonstrate attainment (excunreliable and unrepresentat

ambient data).
3. Planning and control considera

which demonstrate that permanand enforceable emission contrhave been put in place over the several years; SO2 emissions and

concentrations have decreased will continue to decrease in the

foreseeable future in Yellowston

County.
4. Any other air quality‐related

considerations the Administratdeems appropriate, such as the that Yellowstone County has

demonstrated attainment by a

significant margin since the effe

date of the rule.
Newly available air quality data 

Yellowstone County clearly demonstr

– Yellowstone County has been attaining the 

since the effective date of the 2010 SO2 NA
Chart 1: New Data through 2013 show Yellowstone County 

quality is well below SO2 NAAQS level of 75 ppb
Newly available air quality data fo

Yellowstone County clearly demonstrat

– Ambient data from 2010 is non‐representativ

unreliable and should not form the basis for 

nonattainment designation.
Chart 2: SO2 emissions have decreased dramatically in Yell

County over the past several decades.
Chart 3: Since 2008, when significant control equipment be

installed, average annual ambient SO2 readings have met th

standard every year except for 2010.
Chart 4: 2010 doesn’t accurately portray the air quality of

Yellowstone County under the new SO2 NAAQS.
SO2 Monitors and Major Sources in Yellowsto

Phillips 66 Billing

PPL Montan

Western Sugar Coopera

ExxonMobil Bill

CHS Inc. Refinery
Chart 5: All monitors in Yellowstone County showed SO2 des

below the 2010 SO2 NAAQS from 2009‐2013, with the sole 

of Coburn Road, based on questionable 2010 data. Chart 5 

design values for Coburn Road and surrounding monitors fo

2012.

78

70

50

67

63 

0

102030405060708090

Coburn Rd Johnson Lane Brickyard Lockwood (2008‐

2010)

Laurel Pine

SO

2 PPB

Billings Area SO2 Monitors 3‐yr Average Design Value 2010‐2012
Chart 6: All monitors in Yellowstone County show SO2 design valu

the 2010 SO2 NAAQS since the effective date of the rule. Chart 6 

design values for Coburn Road and surrounding monitors fo

2013.*

*Data for last quarter of 2013 have not undergone final QA review. However, any future 

dataset would involve removal of suspect values (if any), and not addition of new values.
– EPA’s use of emissions from 2008 and 201

comparisons to portray 2009 and 2011 em

as uncharacteristically low is misleading. (Cand 3 show consistently lower emissions ithese two years.)

Newly available air quality data fo

Yellowstone County clearly demonstrat
– EPA’s Yellowstone SO2 Designation did not 

all available air quality data, planning and 

considerations, and other relevant air qua

considerations but instead gave unwarran

weight to one questionable outlier year of

monitoring data, resulting in an erroneous

nonattainment designation.

Newly available air quality data fo

Yellowstone County clearly demonstrat
Because the 2009‐2011 design value for

Yellowstone County is within the margin o

EPA must closely examine all ambient dat

area and reject the questionable 2010 da

make such a close call.

– Even minor deviations and quality lapses in the ambie

make it unusable and impact the designation outcom

– The new data further expose EPA’s incomplete reason

any problems with 2010 ambient data are compensat

the use of a three‐year average to determine the desi

however the problematic 2010 data overpower the av

and lead to the erroneous outcome of the designation

– The new ambient data gathered after the effective da

suffer from the same quality concerns and provide a rbasis for a NAAQS designation that is consistent with 

other considerations required under the Clean Air Act
EPA should repeal the Yellowston

Designation and more reasona

weigh the State’s initial designati

available air quality data, plannin

control considerations, and ot

relevant air quality consideratio

make the correct designation
• Because 4 of the past 5 years show ambient S

averages consistently below 75 ppb (2009, 20

2012, 2013 – see Chart 4), and because the

Yellowstone SO2 Designation is such a close c

should not allow the one outlier year of 2010 

based on questionable data to determine the

designation.
• The agency should also recognize and we

more favorably the downward emissions t

presented in Charts

2 and 3.

– EPA gave disproportionate weight to 2008 an

representative emissions levels in its response

comments and technical support documents 

though emissions in both years were elevated 

required control testing.

– The new data make it even more apparent th

and 2010 were exceptions from the consisten

downward trend in SO

2 emissions rather than 

and 2011 being “below past emissions levels.” 

TSD, p. 10)
• Finally, we ask the agency to give proper w

to permanent and enforceable in‐place cothat have recently been implemented rathdiscounting the reductions brought about controls in 2009 and 2011, which have beefurther confirmed in 2012 and 2013.

– The new lower emissions since 2009 have pro

be sustainable and representative.

– The reductions in ambient monitor readings a

emissions in 2009, 2011, 2012, and 2013 conf

effectiveness of these permanent controls.
The Yellowstone SO2 Designatio

unsupported, unnecessary to pr

public health, and will thus cau

unjustified economic harm t

Yellowstone County.