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Technical Support Do cument

PENNSYLVANIA Area Designations For the

2010 SO 2 Primary National Ambient Air Quality Standard

Summary

Pursuant to section 107(d) of the Clean Air Act (CAA) , EPA must designate areas as either

“nonattainment

, ” “attainment

, ” or “unclassifiable” f or the 2010 1

- hour sulfur dioxide (SO 2 ) primary national ambient air quality standard (NAAQS). The CAA defines a nonattainment area as one that does not meet the NAAQS or that contributes to poor air quality in a nearby area that does not meet the NAAQS. Table 1 below identifies the counties or portions of counties in the

Commonwealth of Pennsylvania ( “Commonwealth or “Pennsylvania” or “PA” ) that EPA is initially designating nonattainment based on monitored violations

. EPA is not yet prepared to designat e other areas in Pennsylvania , and will address them in a future final designations action

.

Pennsylvania submitted designation recommendations on June 23, 2011. On February 6, 2013, EPA sent out a letter with intended designations for Pennsylvania. Penns ylvania responded in a letter dated April 8 , 2013. Table 1 below identifies the portions of counties in the

Commonwealth that EPA is initially designating “nonattainment” based on monitored violations

. In Pennsylvania’s April 8 , 2013 letter, they indica ted that only partial counties should be included in the proposed Allegheny, Beaver, and Warren N onattainment A reas and that no portion of Armstrong C ounty should be included in the Indiana County N onattainment A rea. In

addition to comments from the Commo nwealth, EPA received comments from NRG Energy supporting EPA’s proposed nonattainment area for Allegheny County in so far as a portion of Washington County should not be included in the nonattainment area. EPA also received comments from the Allegheny Co unty Health Department and U. S. Steel which indicated that while a portion of Allegheny County should be nonattainment, a portion of Washington County PA should be part of the Allegheny County nonattainment area. Specific technical commen t s from the Com monwealth and the additional comment e rs will be addressed in th is TSD in the

discussion for the appropriate nonattainment areas.

Table 1. Nonattainment Area Designation s for Pennsylvania

Area Pennsylvania’s

Recommended Designations of

Areas/Counties E PA’s Designations of

Areas/Counties

Allegheny, PA Allegheny County (partial) City of Clairton, City of Duquesne, City of Mckeesport, Borough of Braddock, Nonattainment** Nonattainment2

Borough of Dravosburg, Borough of East Mckeesport, Borough of East Pittsburgh, Borough of Elizabe th, Borough of Glassport, Borough of Jefferson Hills, Borough of Liberty, Borough of Lincoln, Borough of North Braddock, Borough of Pleasant Hills, Borough of Port Vue, Borough of Versailles, Borough of Wall, Borough of West Elizabeth, Borough of West Miff

lin, Elizabeth Township, Forward Township, North Versailles Township
Beaver, PA Beaver County (partial) Industry Borough, Midland Borough, Shippingport Borough, Brighton Township, Potter Township and Vanport Township No nattainment Nonattainment

Indiana, PA Indiana County Armstrong County (partial) Elderton Borough Plumcreek Township South Bend Township Nonattainment

Unclassifiable Nonattainment

Nonattainment

Warren, PA Warren County (partial) City o f Warren, Conewago Township, Glade Township, Pleasant Township Nonattainment Nonattainment

* * PA’s response did not include the following portions of Allegheny County: City of Duquesne, Borough of Braddock, Borough of East Mckeesport, Borough of East Pi ttsburgh

, Borough of North Braddock, Borough of Wall, North Versailles Township

Background

On June 2, 2010, EPA revised the primary SO 2 NAAQS (75 FR 35520 )

, by establishing a new 1

- hour standard at a level of 75 parts per billion (ppb) which is met at an ambient air quality monitoring site when the 3

- year average of the annual 99 th percentile of the daily maximum 1

- hour average concentrations does not exceed 75 ppb , as determined in accordance with Appendix T of 40 CFR part 50

. 40 CFR 50.17(a)

- (b). EPA has determined that this is the level necessary3

to provide protection of public health with an adequate margin of safety, especially for children, the elderly and those with asthma. These groups are particularly s usceptible to the health effects

associate d with breathing SO 2

. The Agency is revoking the two prior primary standards of 140 ppb evaluated over 24

- hours, and 30 ppb evaluated over an entire year because the se standards will not add additional public health protection given a 1

- hour standard at 7 5 ppb. Accordingly, EPA is not designating areas in this process on the basis of either of these two prior primary standards. Similarly, the secondary standard for SO 2 has not been revised, so EPA is not designating areas in this process on the basis of the secondary standard.

EPA ’s SO 2 Designation Approach

Section 107(d) of the CAA requires that no later than one year after promulgation of a new or revised NAAQS, state Governors must submit their recommendations for designations and

boundaries to EPA. This deadline was in June 2011. Section 107(d) also requires EPA to provide a notification to states of no less than 120 days prior to promulgating an initial area designation that is a modification of a state’s recommendation. If a state or tribal go vernment
does not submit designation recommendations, EPA will promulgate the designations that it deems appropriate. States and tribal governments were given an opportunity to demonstrate why any proposed modification is inappropriate where their recommen dations disagreed with EPA’s intended designations.

Designations guidance was issued by EPA through a March 24, 2011 memorandum from Stephen D. Page, Director, U.S. EPA, Office of Air Quality Planning and Standards, to Air Division Directors, U.S. EPA Re gions I

- X. This memorandum identifies factors EPA evaluate d in determining boundaries for areas designated nonattainment. These 5 factors include: 1) a ir quality data; 2) e missions and emissions

- related data (location of sources and potential

contributi on to ambient SO 2 concentrations); 3) m eteorology (weather/transport patterns); 4)

g eography

/topography (mountain ranges or other air basin boundaries); and 5) j urisdictional boundaries (e.g., counties, air districts, pre

- existing nonattainment areas, rese rvations, metropolitan planning organization), among any other information deemed relevant to establishing appropriate area designations and boundaries for the 1

- hour SO 2 NAAQS.

The March 24, 2011 memo recommended that area boundaries be defaulted to the county boundary unless additional provided information justifies a larger or smaller boundary than that of the county. EPA believes it is appropriate to evaluate each potential area on a case

- by

- case basis, and to recognize that area

- specific analyses con ducted by states, tribal governments and/or EPA may support a different boundary than a default county boundary.

In this technical support document (TSD), EPA discusses its review and technical analysis of the recommendations submitted by the Commonwealth and other comment e rs in response to EPA’s proposed nonattainment area designations for Pennsylvania for the 1

- hour SO 2 standard which were also made available for public comment (78 FR 11124) on February 15, 2013.

Definitions of important terms used in this document:4

1) Designated “nonattainment” area

– an area which EPA has determined, based on a state recommendation and/or on the technical analysis included in this document, has violated the

2010 SO 2 NAAQS, based on the most recent three years of a ir quality monitoring data, or contributes to a violation in a nearby area.

2 ) Recommended nonattainment area

– an area a s tate or tribal government has recommended

to EPA to be designated as nonattainment.

3 ) Violating monitor

– an ambient air monitor meeting all methods, quality assurance and citing criteria and requirements whose valid design value exceeds 75 ppb, as described in Appendix T of 40 CFR part 50.

4 ) 2010 SO 2 NAAQS

- 75 ppb, national ambient air quality standard for SO 2 promulgated in

20 10. Based on the 3

- year average of the 99 th percentile of the annual distribution of daily

maximum 1

- hour average concentrations

5 ) Design Value

– a statistic that describes the air quality status of a given area relative to the level of the NAAQS.

Non attainment Designations

Introduction

In Pennsylvania’s designation recommendation letter to EPA, dated June 23, 2011, Michael L. Krancer, Secretary of the Pennsylvania Department of Environmental Protection (PADEP),

recommended that Allegheny, Beaver, Ind iana, and Warren Counties be designated as

nonattainment for the 2010 SO 2 NAAQS based on monitored air quality data from 2008

- 2010.

The Commonwealth provided its 5

- factor analysis for each of these four counties as part of its designation recommendation. On April 8, 2013, the Commonwealth submitted a response to

EPA’s 120

- day letter and recommended that only portions of Allegheny County, Beaver and Warren Counties be designated as nonattainment. Pennsylvania also indicated that no portion of Armstrong C ounty should be designated nonat t ainment. EPA received additional comments on the proposed Allegheny County nonattainment area from three comment e rs.

Based on EPA’s technical analysis, EPA is initially designating four areas as nonattainment (Table 1) based on monitored violations of the NAAQS : 1) t he Allegheny, PA Nonattainment

A rea

. which consists of the following p o rtions of the county: City of Clairton, City of Duquesne, City of McKeesport, Borough of Braddock, Borough of Dravosburg, Borough of Eas t McKeesport, Borough of East Pittsburgh, Borough of Elizabeth, Borough of Glassport, Borough of Jefferson Hills, Borough of Liberty, Borough of Lincoln, Borough of North Braddock, Borough of Pleasant Hills, Borough of Port Vue, Borough of Versailles, Boro ugh of Wall, Borough of West Elizabeth, Borough of West Mifflin, Elizabeth Township, Forward Township,

and North Versailles Township ; 2) the Beaver PA Nonattainment Area

, which consists of: Industry Borough, Midland Borough, Shippingport Borough, Brighton Township, Potter Township and Vanport Township ; 3) the Indiana PA Nonattainment Area

, which consists of Indiana County in its entirety and the fo llowing portions of Armstrong County : Elderton5

Borough, Plumcreek Township and South Bend Township ; and 4) the Warren PA

Nonattainment Area

, which consists of the City of Warren, Con e w a go Township, Glade Township, and Pleasant Township.

The 5 factors were used to analyze the nonattainment areas for 1

- hour SO 2 designations :

1. Air quality data

. This factor consi ders the SO 2 air quality monitoring data from EPA’s Air Trends website (see http://www.epa.gov/airtrends/values.html ), including the design

value s (ppb) calculated for each monitor in the area for the three year period 2009

- 2011

. Additional information provided regarding mo nitored data and analysis of data from

2010

- 2012 from the Commonwealth in their response to EPA’s 120 day letters as well as information provided by other comment e r s was also consid e red

. A monitor’s design

value indicates whether that monitor violates a specified air quality standard. The 20 10

SO 2 NAAQS is met at a monitoring site when the identified design value is valid and less than or equal to 75 ppb , as determined in accordanc e with Appendix T of 40 CFR part 50. 40 CFR 50.17(a)

- (b)

. An ambient air monitor whose valid design value exceeds 75 ppb, as described in Appendix T of 40 CFR part 50 is deemed a violating monitor. A design value is only valid if minimum data completenes s criteria are met. A n SO 2 design value that meets the NAAQS is generally considered valid if it encompasses 3 years of complete data. A year is complete when all 4 quarters are complete. A quarter is complete when 75% of the days are complete. A day i s complete when 75% of its hours are complete

. Data substitution tests are described in Appendix T of 40 CFR part 50

. Areas where monitoring data indicate a violation of the 1

- hour, 75 ppb primary SO 2 standard will be designated as nonattainment.

2. Emis sions and em issions

- related data (location of sources and potential contribution to

ambient SO 2 concentrations). EPA reviewed data for the point source and non point source categories from version 3 of the 2008 National Emissions Inventory (NEI) which

is the most current version of the national inventory now availabl e (s ee http://www.epa.gov/ttn/chief/net/2008inventory.html )

, additional emissions information

from the Commonwealth and other c ommenters was considered as well as information

from the EPA 2012 Clean Air Markets Division (CAMD) and Pennsylvania’s EFACTS

system. Generally, the point source inventory represents the bulk of the SO 2 emissions in Pennsylvania

.

EPA examined recent rev isions to the 2008 NEI (version 3) and 2012 CAMD emissions

data and e missions changes appeared to be minimal

.

3. Meteorology (weather/transport patterns). EPA originally eva luated meteorological data to help determine how weather conditions, including wind speed and direction , affect

sources contributing to ambient SO 2 concentrations. The National Weather Service maintains surface and upper air monitoring sites across the Un ited States. Automated Surface Observing System (ASOS) ( http://www.weather.gov/asos ) sites collect hourly averaged wind measurements including wind direction and wind speed. Upper air measurements (rawinsonde) ar e collected at a limited number of sites where vertical wind6

profiles are taken using weather balloons. Measurements taken at ASOS and rawinsonde sites are often used in dispersion modeling analyses using EPA’s AERMOD modeling

system.

One

- minute meteor ological wind fields for an area’s nearby airport(s) were downloaded and run through AERMOD’s preprocessor AERMINUTE to produce hourly averaged wind fields. This data was then run through Lakes Environmental’s WRPLOT software to produce wind roses for the airports, showing predominant wind patterns in the area

.

The Commonwealth also included discussions o n impacts of temperature inversions and

air

- parcel trajector ies from the National Oceanic and Atmospheric Administration’s (NOAA) Air Resource Lab’s HYbr id Single

- Particle Lagrangian Integrated Trajectory or

HYSPLIT model. EPA will discuss some of these analyses in the individual

nonattainment areas sections of this document.

4. Geography/topography (mountain ranges or other air basin boundaries)

. EPA exa mined the physical land features and their possible impacts SO 2 concentrations

. Mountains or other physical features may affect the distribution of emissions, and may help define

boundaries. Maps depicting elevations and point sources were constructed and evaluated to determine the effects of the topography on point source emissions. EPA also

consid ered any additional information provided by the Commonwealth and other

commenter’s in relation to specific areas.

5. Jurisdictional boundaries As discussed in t he Pennsylvania TSD that was included in the docket as part of EPA’s proposal for nonattainment areas (78 FR 11124) on February 15,
2013, EPA reviewed several possible boundaries but generally used county boundaries for the proposed Pennsylvania nonattainm ent areas. In response to EPA’s proposal, Pennsylvania generally recommended that the boundaries for all but one nonattainment area (Indiana) consist of partial counties and that boundaries could be determined based on more local jurisdictions such as cit ies, boroughs, and townships.

Technical Analysis for the Allegheny PA Nonattainment Area

In EPA’s 120 day letter, EPA proposed that the initial Allegheny PA Nonattainment Area consist of Allegheny County in its entirety. In response to EPA’s 120 da y letter, the Commonwealth and the Allegheny County Health Department (ACHD) recommended that only a portion of Allegheny County be included in the final nonattainment area. ACH D also requested that a portion of Washington County also be included in the no nattainment area. A commenter on behalf of US Steel also indicated that a portion of Washington County should be included while a commenter on behalf of NRG Energy agreed with EPA’s original proposal that did not include areas outside Allegheny County. E ach commenter provided some information to support their

response.7

Based on EPA’s technical analysis described below, EPA concurs with the Commonwealth and ACHD to the extent that only a portion of Allegheny County needs to be included as part of this

i nitial nonattainment designation . H owever, EPA is adding some additional municipalities in Allegheny County to the nonattainment area to those municipalities suggested by the

Commonwealth and ACHD. See the information in Table 1for detailed information on municipalities included in the nonattainment area. In regard to Washington County, EPA agrees with the Commonwealth and generally NRG Energy and is not adding a portion of Washington County to the initial nonattainment area as suggested by ACHD and U. S . Steel. The EPA will

address these and other initially excluded areas and their sources in a future final designations

action.

Air Quality Data

This factor considers the SO 2 design values (in ppb ) for air quality monitors in Allegheny County based o n certified data for the 200 9

- 20 11 time period

. As supporting information, t he

Commonwealth and ACDH reported that the preliminary 2010

- 12 design value at the Liberty

monitor , located in the southeast portion of Allegheny County was 141 ppb . Monitors in other portions of Allegheny County and nearby Washington County do not show violations of the standard and have significantly lower concentrations than Liberty. Monitors not showing

violations of the 1

- hour SO 2 NAAQS in other portions of the county suppor t reducing the initial nonattainment area to include only portions of southeastern Allegheny County

.

One

- hour SO 2 design values for the five monitors located in Allegheny County are shown in

Table 2

.

Table 2

. Allegheny County Monitor Trends : 1

- Hour S O 2 99 th % and Design Values in Parts Per Billion (ppb)*

Monitor

Name Monitor

Air Quality System ID 99 th % Design

Value Design

Value

2007 2008 2009 2010 2011 2008

- 10 2009

- 11

Avalon 42

- 003

-

0002 70 75 61 53 40 63 51

Carnegie 42

- 003

-

0010 75 62 61 35 23 53 40

Liberty 42

- 003

-

0064 192 111 131 141 165 128 146

South Fayette 42

- 003

-

0067 74 52 53 39 28 48 40

* Monitor in bold has the highest 200 9

- 201 1 design value in the respective county.

The Commonwealth also included an analysis of exceedances from 2 010

- 12. They noted that exceedances at the Liberty monitor primarily occurred during the overnight hours and further8

explained that this tendency for exceedances to occur during the overnight hours was due to nocturnal inversions interacting with local em ission sources. EPA reviewed exceedances from 2007 to 2011 and found a similar pattern with elevated SO 2 concentrations occurring at the Liberty monitor primarily during the overnight hours. Similar patterns are also observed in Liberty’s PM

- 2.5 concentr ations.

Emissions and Emissions

- Related Data

Emissions

Table 3 shows total emissions of SO 2 in tons per year (tpy) for sou r ces in and around the Allegheny Area and sources emitting or contributing greater than 100 tpy of SO 2 according to

the 2008 NEI

.

Table 3

. SO 2 Emissions in Allegheny Area

County Facility

Located in

State ’s Original

Recommended

Nonattainment

Area? Facility Name 2008 NEI

Total Facility

SO 2 Emissions (tpy) 2011

eFACTS

Total Facility SO 2 Emissions (tpy) ** CAMD 2012

SO 2 Emis sions (tpy) except as

noted

Allegheny Yes Us Steel Corporation

- Irvin Plant 475 419

Allegheny Yes Shenango Inc 333 372

Allegheny Yes Orion Power

Midwest

Cheswick

Station 30,300 9,290 1,911

Allegheny Yes Uss Corporation

- Edgar

Thoms on Works 1,536 1,279

Allegheny Yes Uss

- Clairton

Works 1,517 1,468

Allegheny Yes Bellefield Boiler

Plant 795 0.4

Allegheny Yes Bay Valley Foods, LLC 487 313

Washington No Orion

Power/Elrama

Power Station 2,572 428 250

Washington No Alleghe ny Energy/Mitchell

Power Station 934 864 1,570

Westmoreland No Arcelormittal

Monesson 3969 LLC/Monesson

Coke Plant Washington No Langeloth Metallurgical 186 31

** 2011 SO 2 emssions from PA DEP eFACTS ( http://www.ahs.dep.pa.gov/eFACTSWeb/criteria_faci lityemissions.aspx )

The Commonwealth provided an analysis of exceedances in 2012 at the Liberty monitor and daily emissions from the Elrama facility. It should be noted that according to the comment letter from NRG Energy and other comments from the Commonwealth that the Elrama facility has not been operating since June 2012

. However

, CAMD indicates that Elrama Unit 4 operated for 342 hours in the third quarter of 2012 but no units at Elrama operated since that time through first quarter of 2013

. NRG also indicated that more exeedances were recorded at the Liberty monitor

between 2010

- 2012 versus 2007

- 2009 even though emissions from the Elrama facility were much higher during 2007

- 2009. The Commonwealth also provided analys e s showing that o n 23 days of exceedances at the Liberty monitor in 2012 the Elrama facility was only operating on three of those days and emitted less than 10 tons of SO 2 on any of the three days. While ACHD reviewed 2010 emissions data, they simply identified sources th at would need further analysis based on EPA’s Q/d methodology. U. S. Steel also generally contends that the area where the Elrama facility is located should be included in the nonattainment area but this view is not informed by more recent information suc h as the analysis provided by the Commonwealth indicating that more recent emissions from Elrama appeared to have little impact on exceedances of the standard especially in 2012. Therefore there does not appear to be sufficient information

to include the Elrama facility in Washington County in the initial nonattainment area at this time

, and we will further address this source in a future final designations action

.

In addition to Elrama

, EPA extracted the Mitchel l power plant’s SO 2 emissions data from it s CAMD website for 2011 and 2012. Mitchell ’s emissions (from CAMD) increased from 862 tpy in 2011 to 1,570 tpy in 2012 . This was primarily due to an increase in hours of operation for

Mitchell’s large coal unit . This unit was operated for 4,756 hrs in 2 011 and 6,047 hrs in 2012. Averaged annual emissions at Mitchell were relatively unchanged between 2011 (0.21 lbs/MMbtu) and 2012 (0.25 lbs/MMbtu). Mitchell’s coal unit is controlled and appears to be well operated

, achieving about 90% removal efficiency on average. EPA does not feel there is

sufficient information to includ e the Mitchell power plant in the initial nonattainment area at this time, and will further address this source in a future final designations action

. Also other sources in Washington county and Westmoreland County in the table above appear to have relatively small emissions and are not likely to be contributing to violations in Allegheny County. These areas and sources will be addressed in a future designations action.

The Cheswic k power plant appears to be the largest SO 2 emission source in Allegheny County.

Cheswick’s emission s , however, have been significantly scaled back since inst a llation and operation of its SO 2 control equipment. Information from EPA’s CAMD website indica te s a large decrease in between the 2011 and 2012 annual SO 2 emissions which is primarily due to increased control efficiency. In 2011, Cheswick’s coal

- fired unit ran for 6,160 hrs at an annually averaged emission rate of 0.71 lbs/MMbtu. In 2012, Cheswic k’s coal unit ran slightly less at10

5,715 hrs with an annually averaged emission rate of 0.15 lbs/MMbtu. In light of Cheswick’s

lower emission rates

, distance (~24 km) from the Liberty monitor , and minimal change in the monitored values at Liberty , EPA is not prepared at this time to include this source in the initial

nonattainment area , and will further address it in a future final designations action

.

EPA summarized SO 2 emissions from PA DEP’s eFACTS in table 3. After the Cheswick power plant, the next three largest SO 2 emission sources are U.S. Steel facilities. These include the Clariton Coke Works, the Edgar Thompson Works and the Irvin Plant, which are considered part

of U.S. Steel’s Mon Valley Works . County emissions suggest these three U.S. st eel facilities

should be included in the nonattainment area.

Meteorology (weather/transport patterns)

Evidence of source

- receptor relationships between specific emissions sources and high SO 2 values at violating monitors is another important factor in de termining the appropriate contributing areas and the appropriate extent of the nonattainment area boundary. For this factor,

EPA considered data from sites that collected hourly averaged wind measurements including wind direction and speed for 5 years. T here are two meteorological monitoring sites currently operating in Allegheny County. An ASOS and rawinsonde site is located at the Pittsburgh International Airport in the western part of the county. Another ASOS site is located at the Allegheny County A irport in the southern portion of the county. The Allegheny County Airport site is closer to the Liberty monitor. Recent wind data from both airports was downloaded and run through AERMOD’s preprocessor AERMINUTE to produce hourly averaged wind fields. These data were in turn run through Lakes Environmental’s WRPLOT software to produce wind roses for both of the surface ASOS sites in Allegheny County and shown below in Figure 1

.

Figure 1

.11

Wind rose plots for Pittsburgh International and Allegheny County airports show differing wind distribution patterns. As shown in the map in Figure 5

, the prevailing wind directions at the Allegheny County Airport are predominantly out of the south and west. At the Pittsburgh International Airport, the prevailin g winds are predominantly out of the west/southwest. These different wind patterns suggest source emission distributions may be dependent on their locations within the county. Differing wind patterns between the two ASOS sites are probably due to the

cou nty’s complex topography (see explanation under Geography/topography ).

The Commonwealth conducted an analysis of the Liberty monitor’s wind measurements from 2010 through 2012. They specifically examined winds during hours in which the Liberty

monitor ex ceeded the 1

- hr SO 2 NAAQS and then compared them to the entire data set. Winds were mainly from the southwest during exceedance hours. A similar wind direction tendency was noted for the entire data set though it was not as pronounced as the exceedance o nly wind

fields.

EPA conducted a similar analysis using winds from the Allegheny County Airport, located about 4.5 km to the northwest of the Liberty monitor. Pennsylvania noted that the Allegheny Airport sits at a higher elevation than the Liberty monit or and therefore may not measure some of the local wind patterns that are thought to contribute to the Liberty monitor’s exceedances of the 1

- hr SO 2 NAAQS.

EPA downloaded the 1

- minute ASOS files for 2009 through 2011 and processed them into one

hour wind files using its AERMET preprocessor. Adjustments were made to the ASOS wind

data to account for local time. The one

- hour AERMET wind files were then processed using12

Lakes Environmental’s WRPLOT program to produce a wind rose for those hours (with valid

w ind data) that exceeded the 1

- hr SO 2 NAAQS. EPA constructed a wind rose, shown in figure 2

is similar to the one that Pennsylvania constructed . This suggests local flow patterns and possibly the nonattainment problem in general may be slightly more wides pread than indicated

in the Commonwealth’s analysis.

Figure 2

.

Geography/topography (mountain ranges or other air basin boundaries)

Allegheny County is made up of the high elevations of the Appalachian Mountains with dendridic valleys carved out by the Ohio, Allegheny and Monongahela rivers systems. Higher terrain lies to the southeast (Laurel Ridge). Elevation differences between the river valleys and the ridge tops can exceed 150 meters. See Figure 3 below.13

Most of the large (>100 tpy) p oint sources in Allegheny County reside within the river valleys. This is important since these valleys can create complex wind patterns which will impact sources with low stacks that cannot overcome neighboring elevated terrain causing the emissions to b e trapped within the valleys. The ASOS meteorological sites in Allegheny County are both located in the higher elevations of the county. This presents a problem in that the meteorological measurements may not be representative of the valley flows that ca n occur under certain atmospheric conditions. These atmospheric conditions may define the times of peak concentrations for some emissions sources (low stacks for example). Therefore, the large sources residing within the river valleys are likely to cause localized air quality problems.

Figure 3

.

Jurisdictional boundaries

EPA provided information about all boundaries considered prior to proposing nonattainment areas and this information can be found in the Pennsylvania TSD as part of the docket on proposed designations (78 FR 11124) and is not restated here. EPA originally proposed including all of Allegheny County in the initial nonattainment area. However additional information provided by the Commonwealth and ACHD in response to EPA’ s proposal demonstrates that the monitors and sources of concern within Allegheny County are only a portion of the county. However EPA noted that the area of the county suggested for inclusion by

the Commonwealth and ACHD as part of the Allegheny PA Nonat tainment Area did not include potions of the county where the Edgar Thompson Works was located. EPA feels this source is14

impacting SO 2 values in the county and has also included this portion of the county in the initial

nonattainment area. Therefore, EPA is designating the portions of Allegheny County as

id e ntified in Table 1 as nonattainment.

Conclusion for the Allegheny Nonattainment Area

After considering t he factors described above, EPA finds that the portion s of Allegheny County

that are nonatta inment for the 2010 SO 2 NAAQS include the following: City of Clairton, City of Duquesne, City of Mckeesport, Borough of Braddock, Borough of Dravosburg, Borough of East Mckeesport, Borough of East Pittsburgh, Borough of Elizabeth, Borough of Glassport, Bo rough of Jefferson Hills, Borough of Liberty, Borough of Lincoln, Borough of North Braddock, Borough of Pleasant Hills, Borough of Port Vue, Borough of Versailles, Borough of Wall, Borough of West Elizabeth, Borough of West Mifflin, Elizabeth Township, For ward Township,

and North Versailles Township . These areas are identified in Table 1 with the area name Allegheny PA Nonattainment A rea

. Refer to Figure 4 for a depiction of the nonattainment area.

The air quality monitor which is the Liberty monitor in this area of Allegheny County shows

violation s of the 2010 SO 2 NAAQS, based on certified 200 9

- 201 1 air quality data and additional data from 2012 provided by the Commonwealth and ACHD. Additionally, in response to EPA’s

120

- day letter, the Commonwealth a nd ACHD provided supporting information as referenced in the five factor analysis that assisted EPA in concluding that only a portion of Allegheny County

should be initially included in the Allegheny County, PA Nonattainment Area , leaving remaining portion s to be addressed in a future final designations action

. Available emissions,

m eteorological data, and geographical data suggest that the sources in the cities, boroughs and townships as identified in Table 1 co ntribute to SO 2 NAAQS violations in Allegheny County.

Current information about sources located in Washington County as described above is not

sufficient for us to conclude at this time to that they are likely to contribute to nonattainment at the Liberty monitor in Allegheny County. We wil l further address these sources in a future final designations action.

Based on the consideration of all the relevant and available information, as described above, EPA believes that the boundaries described herein encompass the nonattainment area based on the violating monitor in Allegheny County in Pennsylvania. Areas and sources that we are not yet prepared to conclude are contributing to the monitored violation or to other possible

violations are not included in this initial nonattainment area. In a subsequent round of designations we will further address such areas and sources and make final designations decisions for areas that are not currently included in the nonattainment area designation

addressed in this TSD.

Figure 4

.15

Technical Analysis for the Beaver Nonattainment Area

In EPA’s 120 day letter, EPA proposed that the initial Beaver PA Nonattainment Area consist of Beaver County in its entirety. In response to EPA’s 120 day letter, the Commonwealth

recommended that onl y a portion of Beaver County ( Industry Borough, Shippingport Borough, Midland Borough, Brighton Township, Potter Township and Vanport Township ) be included in the nonattainment area and provided an analysis to support their response.16

Based on EPA's tech nical analysis described below, EPA agrees with Pennsylvania’s

recommendation and is initially designating a portion of the county as nonattainment for the

2010 SO 2 NAAQS based on the violating monitors in Beaver County. The Beaver PA

N o nattainme nt Area co nsists of Industry Borough, Shippingport Borough, Midland Borough, Brighton Township, Potter Township and Vanport Township

.

Air Quality Data

This factor considers the SO 2 air quality monitoring data, including design values (in ppb)

calculated for all air quality monitors in Beaver County based on certified data for the 200 9

- 20 1 1 period

. In addition, more recent air monitoring data included in the Commonwealth ’ s response to EPA’s proposal was also considered.

The 201 1 1

- hour SO 2 design value for the monitor s located in Beaver County is shown in Table

4

.

Table 4

. Beaver County Monitor Trend s: 1

- Hour SO 2 99 th % and Design Value in Parts Per Billion (ppb)

Monitor Name Monitor

Air Quality System ID 99 th % Design

Value Design

Value

2007 2008 2009 2 010 2011 2008

- 10 2009

- 11

Hookstown 42

- 007

-

0002 153 122 109 72 58 101 80

Brighton Township 42

- 007

-

0005 170 165 176 161 136 167 158

One

- hour SO 2 design values at the Hookstown monitor have been falling over the last several

years. As supporting informat ion, t he Commonwealth indicated that the preliminary 2012 design value for this monitor is 57 ppb while the 2012 design value at the B r ighton monitor was 149 ppb. These values were confirmed by EPA. Monitors within the 50 kilometer zone of the violating monitors in the neighboring counties in PA (Lawrence, Alleg h eny and Washington) are not recording violations

.

The Commonwealth also looked at exceedances at the Brighton Township and Hookstown monitors in Beaver County. Both monitors showed distinctly di fferent patterns as to when 1

- hr

SO 2 exceedances occurred. The Brighton Township monitor tended to have exceedances during the overnight hours while exceedances at the Hookstown monitor tended to occur during the daytime hours. EPA examined 1

- hr SO 2 conc entrations from 2009

- 11 for both monitors and generally confirmed the Commonwealth’s findings. EPA would add that while exceedances at the Brighton Township monitor generally occurred during the overnight hours, there were still a

number of exceedances ob served during the daytime. EPA also calculated the correlation coefficients for both the Brighton Township and Hookstown monitors. One

- hour SO 2 concentrations from the Brighton Township and Hookstown monitors are not well correlated, which supports desig nating only a portion of Beaver County as nonattainment.17

Emissions and Emissions

- Related Data

Emissions

In respon s e to EPA’s letter, the Commonwealth indicated that four major source s with SO 2 emissions over 100 tpy for the 2008

- 2011 period ar e locat ed within 5 miles of the Brighton Township monitor

, which is still showing violations of the NAAQS. The Commonwealth

identified the sources as: Jewel Acquisition

- Midland, First Energy Gen eration B r uce Mansfied

, Alleghency Energy Beaver Valley and Horseh e ad Corporation

- Monaca Smelter. All of these

sources are included in the portion of Beaver County that is designated nonattainment

. Table 5 shows total emissions of SO 2 in tons per year (tpy) for source s in and around the Beaver

Area which are emitting gr eater than 100 tpy of SO 2 according to the 2008 NEI.

Table 5

. SO 2 Emissions in the Beaver Nonattainment Area

County Facility

Located in Original State

Recommended

Nonattainment

Area? Facility Name

CAMD 2012

Total SO 2 Point Emissions (tpy) To tal Facility

SO 2 Emissions

2008 NEI

v3 (tpy)

Beaver , PA Yes First Energy/Bruce

Mansfield Plant 11,019 19,082

Beaver , PA Yes Horsehead Corp./Monaca

Smelter 3,320

Beaver , PA Yes AES Beaver Valley 3,113 3,205

Jefferson,

OH Yes W.H. Sammis

Plant 102,1 97 4,064

Jefferson,

OH Yes Cardinal Power

Plant 33,317 8,144

Jefferson,

OH Yes Severstal Wheeling, Inc. 700

Westmore

land, PA No Arcelormittal

Monesson

LLC/Monesson

Coke Plant 396

Brooke

, WV Yes Mountain State Carbon, LLC 731

Hancock

, WV Yes Arcel ormittal

Weirton Inc. 597

Lawrence,

PA No Orion Power

Midwest/New

Castle Power

Plant 12,923 4,995

Lawrence,

PA No ESSROC/

Bessemer 91018

Lawrence,

PA No CEMEX/ Wampum

Cement Plant 674

Allegheny

, PA Yes Shenango Inc 333

Allegheny

, PA Yes Bellefi eld

Boiler Plant 795

Allegheny

, PA Yes Bay Valley Foods, LLC 487

CAMD Emissions Analysis

Emissions from sources included in EPA’s CAMD database ( http://c amddataandmaps.epa.gov/gdm/index.cfm?fuseaction=emissions.wizard ) were reviewed to determine if more recent emissions are available for sources near the Beaver County monitors.

Not all emissions sources within 50 km of the Beaver County monitor s are incl uded in the

CAMD database ; o nly five of the 15 sources within 50 km of the Beaver County monitor s reported their SO 2 emissions to the CAMD database. These sources and their reported annual

emissions are listed in Table 6 along with their distance from the nearest monitor in Beaver County.

Table 6

. CAMD 2008

- 1 2 Emissions Summary of SO 2 Emissions in tpy

Facility County Distance* CAMD

2008 CAMD

2009 CAMD

2010 CAMD

2011 CAMD

2012

AES Beaver Valley Beaver 3.2 Not

Available 3,500 3,416 3,086 3,205

First

Ene rgy/Bruce

Mansfield Beaver 7.6 11,117 17,704 21,757 21,196 19,082

W

. H

. Sammis

Plant Jefferson 11.3 102,619 73,614 12,761 4,202 4,064

Orion Power/New

Castle Power

Pl an t Lawrence 28.1 12,923 7,629 9,572 7,510 4,995

Cardinal Power

Plant Jefferson 36.6 32, 497 34,751 32,522 25,200 8,144

*Distance from Beaver County SO 2 monitor in kilometers.

Emissions Controls

EPA has evaluated additional information from the 2008 NEI and CAMD and notes that

SO 2 emissions at four of the five CAMD sources have operating S O 2 controls on at least some of their units. The Bruce Mansfield and AES Beaver Valley plants had wet scrubbers installed prior to 2008. The Cardinal and W. H. Sammis power plants in Jefferson County, OH recently19

installed wet scrubbers on their units. SO 2 emissions from the W. H. Sammis plant have fallen significantly since the installation and Cardinal’s emissions have decreased as well . Declining emissions at the W. H. Sammis plant may be responsible for the declining SO 2 concentrations

observed at t he Hookstown monitor near the PA

- WV border. The Commonwealth also indicated

that the decline in SO 2 at the Hookstown monitor was likely du e to SO 2 controls at major power plants to the west of Beaver County. At this time EPA is not including any portions of counties outside of Beaver county in the nonattainment area since it is unlikely they are impacting the remaining violating monitor in Beaver County. In some instances sources may be included in

other initial nonattainment areas. Areas and sources tha t we are not yet prepared to conclude are contributing to the monitored violation or to other possible violations are not included in this initial nonattainment area. In a subsequent round of designations we will further address such

areas and sources and make final designations decisions for areas that are not currently included in the nonattainment area designation addressed in this TSD.

Meteorology (weather/transport patterns)

Evidence of source

- receptor relationships between specific emissions sou rces and high SO 2 values at violating monitors is another important factor in determining the appropriate contributing areas and the appropriate extent of the nonattainment area boundary. For this factor,

EPA considered data from sites that collected hour ly averaged wind measurements including wind direction and speed for 5 years. There are two ASOS sites located within 50 km of the Beaver County monitors. The closest surface site is at the Pittsburgh International Airport located approximately 22

- 23 kil ometers from either of the Beaver County monitors. The next closest ASOS site is the Wheeling/Ohio County Airport located approximately 44 and 61 kilometers from the Beaver County monitoring sites. The closest rawinsonde site is located at the Pittsburgh International Airport located in western Allegheny County approximately 22

- 23 km from the monitoring sites

.

One

- minute meteorological wind fields for the Wood County Airport site was downloaded and run through AERMOD’s preprocessor AERMINUTE to produce h ourly averaged wind fields. This data was then run through Lakes Environmental’s WRPLOT software to produce wind roses for both sites ( Figure 5 ). Predominant winds at the Pittsburgh International Airport were generally from the west over the 2006

- 10 time period, while winds at the Wheeling Ohio County Airport were generally from the southwest. Given this information, EPA is not prepared at this

time to conclude that large sources in Lawrence County (ie. ESSROC/Bessemer, Orion Power

New Castle Power Plant , and CEMEX/Wampum Cement Plant ) are likely to contribute to the violating monitor s in Beaver County. We will further address these sources in a future final designations action.

The Commonwealth presented wind roses from the Brighton Township monitor fo r periods when

the monitor exceeded the 1

- hr SO 2 NAAQS and the entire period. Wind directions were generally limited to a southerly direction during hours when 1

- hr SO 2 concentrations exceeded the NAAQS. Pennsylvania suggested that the predominant wind d irections during periods of

exceedances were due to inversions and local sources.20

EPA examined stack heights from the 2005 NEI for the four local sources included in Pennsylvani a ’s proposed nonattainment area. Three of the four sources (Bruce Mansfield, AES Beaver Valley, Horsehead Corporation) have stacks exceeding 200 ft making emissions from these sources difficult to trap under nocturnal inversions. Additional information on this topic is

found in the section below. Despite this shortcoming, EPA gene rally agrees that local sources are impacting the Brighton Township monitor.

Figure 5

.

Geography/topography (mountain ranges or other air basin boundaries)

The Ohio and Beaver rivers divide Beaver County into roughly three portions. The Ohio River traverses across the county in a roughly east

- west direction while the Beaver River flows south into the Ohio River near the Borough of Beaver. The river valleys within Beaver County create sharp contrasts with the surrounding mountains in west ern Pennsylvania. Elevations in the valleys are in the 220

- 230 meter range. Higher terrain in the county rises to over 350 meters above mean sea level. Terrain can change quite abruptly between the rivers and the mountains. In neighboring Allegheny Cou nty complex valley flows have been noted. These types of flow regimes probably exist in the river valleys of Beaver County also. This is important because the vast majority of large point sources reside in the river valleys. The Commonwealth also provid es similar analyses in their response.21

As noted in the section on Meteorology, EPA examined stack heights from the 2005 NEI. This

information in addition to elevation information was used to determine the approximate release height for the four (4) sour ces nearest the Brighton Township monitor. Stack heights at Bruce Mansfield are listed at 950 ft making the release height well above the surrounding terrain and ensuring that emissions from this source are not overly influenced by nocturnal inversions. Stack heights at the Jewel Acquisition/Midland facility are generally less than 80 ft making impact from this source more local. Stack heights at AES Beaver Valley and Horsehead Corporation are in the 200

- 400 ft range. Release heights for both of these s ources are approximately the same elevation as the Brighton Township monitor making direct impacts from these sources more likely. This may explain the wind patterns during periods of exceedances

that the Commonwealth included in its analysis.

Jurisdict ional boundaries

EPA provided information about all boundaries considered prior to proposing nonattainment areas and this information can be found in the Pennsylvania TSD as part of the docket on proposed designations (78 FR 11124) and is not restated he re. EPA originally proposed including all of Beaver County in the nonattainment area. However additional information provided by the Commonwealth in response to EPA’s proposal demonstrates that the monitors

and sources of concern in this area of the Comm onwealth that are most likely impacting the violating monitor are all located in Industry Borough, Shippingport Borough, Midland Borough, Brighton Township, Potter Township and Vanport Township . Therefore, EPA is designating these portions of Beaver Count y as the initial Beaver PA N ona ttainment Area

.

Conclusion for the Beaver PA Nonattainment Area

After considering t he factors described above, EPA finds that the boundary for the portion of Beaver County, PA with a current violating monitor consists of the portion of Beaver County

that include Industry Borough, Shippingport Borough, Midland Borough, Brighton Township, Potter Township and Vanport Township

.

The air quality monitor in this area of Beaver County show s violation s of the 2010 SO 2 NAAQS,

ba sed on certified 200 9

- 201 1 air quality data and additional data from 2012 provided by the

Commonwealth. Available emissions, m eteorological data, and geographical data suggest that

the sources in the boroughs and townships located within about a 5 km radi us of the B r ighton Township monitor likely impact and contribute to monitored SO 2 NAAQS violations in B eaver County. Some sources outside Beaver County are also being included in other nonattainment

areas in W est Virginia. Since the Hookstown monitor is now not showing a violation and sources likely impacting Hookstowsn have recently had emissions decreases due to the

installation and use of SO 2 controls, we are not prepared to conclude that additional areas in the county are likely having a significant i mpact on the B righ ton monitor. Therefore such other areas in the county are not included in the initial Beaver PA N onattainment Area , and will be further addressed in a future final designations action

.22

Additionally, in response to EPA’s 120

- day letter, the Commonwealth provided supporting information as referenced in the five factor analysis that assisted EPA in concluding that only a portion of Beaver County should be included in the initial Beaver PA Nonattainment Area.

Based on the consideration of all the relevant and available information, as described above, EPA believes that the boundaries described herein encompass the initial non attainment area

based on the violating monitor in Beaver County in Pennsylvania. Areas and sources that we are

not yet prepared to conclude are contributing to the monitored violation or other potential

violations are not included in this initial nonattainment area. In a subsequent round of designations we will further address such areas and sources and make final des ignations decisions for areas that are not currently included in the nonattainment area designation

addressed in this TSD.

Figure 6

.23

Technical Analysis for the Indiana Nonattainment Area

In EPA’s 120 day letter, EPA proposed that the initial Indiana PA Nonattainment Area consist of Indiana County in its entirety and a portion of Armstrong County ( Elderton B orough

, Plumcreek Township and South Bend Township ). In response to EPA’s 120 day letter, the Commonwealth agreed that Indian a County in its entirety should be nonattainment but recommended that no portion of Armstrong County be included in the nonattainment area.

Based on EPA's technical analysis described below, EPA agrees in part with the

Commonwealth ’ s response and is i nitially designating all of Indiana County as nonattainment.

EPA , however, disagrees with the Commonwealth’s recommendation regarding Armstrong County and is also designating the originally proposed portion of Armstrong County along with

all of Indiana Co unty as nonattainment for the 2010 SO 2 NAAQS.

Air Quality Data

This factor considers the SO 2 air quality monitoring data, including design values (in ppb)

calculated for the 2009

- 11 time period for all air quality monitors within 50 kilometers of the

I ndiana County monitor

.

The 20 09

- 1 1 1

- hour SO 2 design value for the Strongstown monitor located in Indiana County is

shown in Table 7

. The Commonwealth also provided data indicating that the 2012 design value was 81 ppb and EPA verified this design value i s correct.

Table 7

. Indiana County Monitor Trend : 1

- Hour SO 2 99 th % and Design Value in Parts Per Billion (ppb)

Monitor

Name Monitor

Air Quality System ID 99 th % Design

Value Design

Value

2007 2008 2009 2010 2011 2008

- 10 2009

- 11

Strongstown 42

- 0 63

-

0004 88 92 82 95 68 90 82

The Commonwealth presented information regarding the timing and occurrence of 1

- hr SO 2 NAAQS exceedances and noted that exceedances at Strongstown generally occurred during the daytime hours . EPA examined Strongstown’s SO 2 concentrations from the 2009

- 11 time period

and confirmed that exceedances of the 1

- hr SO 2 NAAQS generally occur during the daylight hours though overnight peak concentrations at Strongstown can still be quite high

. The Commonwea l th also examined and compa red design value trends at the Strongstown

monitor in Indiana County, PA and the York monitor in York County, PA. The York monitor

has show n significant decreases in 1

- hr SO 2 concentrations after the installation of SO 2 controls24

at the nearby Brunner Isla nd power plant. In contrast, the Commonwealth pointed out that

concentration trends at Strongstown have show n little decline even with controls being installed

at the nearby Keystone power plant in Armstrong County and suggest ed that this lack of change at the Strongstown monitor indicates sources other than Keystone are impacting the monitor.

EPA reviewed the number of exceedances at Strongstown over the 2007

- 2011 time period and found a slight decrease in the number of 1

- hr SO 2 exceedances (see Table 7 ). This result may indicate that while controls at Keystone may not be affecting overall SO 2 concentrations as much as observed near the Brunner Island power plant they likely contributed to fewer exceedances (post 2009) meas ured at the Strongstown monit or. This result suggests Keystone is still impacting the monitor. Note that no statistical analysis was performed on the Commonwealth’s analysis of design value trends or EPA’s analysis of exceedance trends.

Table 7 . Indiana County Monitor Exceedan ce Trend: 1

- Hour SO 2 Exceedances over the

2007

- 11 Time Period

2007 2008 2009 2010 2011 Strongstown Exceedances 11 8 4 7 2

Emissions and Emissions

- Related Data

Evidence of SO 2 emissions sources in the vicinity of a violating monitor is an important factor for determining whether a nearby area is contributing to a monitored violation. For this factor, EPA evaluated county

- level emission s data for SO 2 and any change in SO 2 emitting activities since the date represented by those emissions data

.

Emissi ons Table 8 shows total emissions of SO 2 in tons per year (tpy) for violating and potentially contributing counties in and around the Indiana County Area in Region III and sources emitting greater than 100 tpy of SO 2 according to the 2008 NEI.

Table 8

. SO 2 Emissions in the Indiana Nonattainment Area

-

County Name Total Facility SO 2 Emissions (tpy) 2008

NEI CAMD 2012 Total

SO 2 Point Emissions (tpy) Facility

Located in

State

Recommended

Nonattainment

Area?

Indiana

, PA Yes Homer City Generating

Station 102,486 99,774

Indiana

, PA Yes Seward Generating

Station 15,549 4,333

Indiana

, PA Yes Genon Conemaugh 6,286 6 ,3 1225 Plant Armstrong

, PA No Keystone

Power

Station 189,983 29,420

Cambria,

PA No Colver Power Project 2,576 2

, 547

Cambria,

PA No Cambria Cogen 2,782 1,755

Cambria,

PA No Ebensburg Cogen 1,815 2,033

Blair, PA No Norfolk

Southern Railway Co/

Juniata

Locomotive Shops 392

SO 2 emissions for 2011 are available on PA DEP’s eFACTS website ( http://www.ahs.dep.pa.gov/eFACTSWeb/criteria_facilityemissions.aspx ). Surveying the 2011 regional emission information confirms that Keystone was the second largest point source in t he

Commonwealth behind Ho mer Cit y.

CAMD Emissions Analysis

Emissions from sources included in EPA’s CAMD database ( http://camddataandmaps.epa.gov/gdm/index.cfm?fuseaction=emissions.wizard ) we re reviewed to see if more recent emissions are available for sources near the Indiana County, PA monitor. Nearly all of the emission sources within 50 km of the Indiana County monitor are included in the CAMD data base since the monitor is essentially su rrounded by electric

- generating units.

Table 9

. CAMD 2008

- 1 2 Emissions Summary of SO 2 Emissions in tpy

Facility County Distance * CAMD

2008 CAMD

2009 CAMD

- 2010 CAMD

- 2011 CAMD

2012

Colver Power Project Cambria 10.3 Not

Available 30,759 2,901 2,881 2,54 7 Ebensburg Cogen Cambria 18.9 Not

Available 2,044 2,404 1,937 2.003

Seward Power

Plant Indiana 19.8 7,771 7,756 8,458 7,003 4,333

Cambria Cogen Cambria 20.4 Not

Available 6,947 2,070 1,942 1,755 Conemaugh Indiana 23.2 6,282 7,222 7,056 7,189 6,312 Homer City Generating

Station Indiana 24.1 102,484 101,334 112,95

1 83,596 99,774

Keystone Armstro

ng 37.1 189,994 113,137 39,114 46,441 29,420

*Distance from Indiana County, PA SO 2 monitor in kilometers.26

Emissions Controls

EPA’s review of the coal

- fired EGU sources within 50 km of the Indiana County monitor

indicates that all of the facilities have some sort of SO 2 emission controls currently operating or planned to be operating (as of 2010). Only two sources were projected to have controls i nstalled after 2008 (Keystone and Homer City). According to EPA’s National Electric Energy Data System (NEEDS) database ( http://www.epa.gov/airmarkt/progsregs/epa

ipm/ BaseCasev410.html#needs )

, the only uncontrolled units within 50 km of the Indiana County monitor are two units at Homer City (see Table 1 0 below).

Table 1 0

. Summary of Controls Within 50 km of Strongstown Monitor (from NEEDS database)

Plant Name Un it

ID County Capacity

(MW) On

Line

Year Modeled

Fuels Wet/DryScrubber Scrubber

Online
Keystone 1 Armstrong 850 1967 Bituminous Wet Scrubber 2009
Keystone 2 Armstrong 850 1968 Bituminous Wet Scrubber 2009
Cambria Cogen B1 Cambria 44 1991 Waste Coal Reage nt Injection
Cambria Cogen B2 Cambria 44 1991 Waste Coal Reagent Injection

Colver Power Project ABB01 Cambria 110 1995 Waste Coal Reagent Injection
Ebensburg Power 031 Cambria 49.5 1990 Waste Coal Reagent Injection
Conemaugh 2 Indiana 850 1971 Bitu minous Wet Scrubber 1995
Conemaugh 1 Indiana 850 1970 Bituminous Wet Scrubber 1994 Homer City

Station 1 Indiana 620 1969 Bituminous Homer City

Station 2 Indiana 614 1970 Bituminous Homer City

Station 3 Indiana 650 1977 Bituminous Wet Scrubber 2001

Seward 1 Indiana 260.5 2004 Waste Coal Dry Scrubber 2004

Seward 2 Indiana 260.5 2003 Waste Coal Dry Scrubber 2004

The Commonwealth noted the controls recently installed on Keystone U nits 1 and 2. These

controls decreased Keystone’s SO 2 emissions by a pproximately 85% in 2012

. Annual SO 2 emissions data for Keystone and Conemaugh, which are similarly sized facilities, was pulled

from EPA’s CAMD website. Table 10 shows annual emissions and emission rates (in lbs/MMbtu) for both plants in 2012. This tab le shows that while both plants are similar in size27

their annual emissions and average annual emission rates are significantly different. Keystone’s annual emissions are four and a half times larger than Conemaugh even though Keystone’s units

were run les s than Conemaugh’s in 2012. Keystone’s units average annual emission rate was four to almost six times higher than Conemaugh. This illustrates that while emission controls are important, control efficiency may be equally important.

Table 1 1 . Keystone a nd Conemaugh’s 2012 CAMD SO 2 Emissions with calculated average

annual emission rate in lbs/MMbtu.

Facility

Name County Unit

ID Year SO2

(tons) Heat Input

(MMBtu) Operating

Time Gross

Load (MW

- h) Avg

lbs/Mmbtu
Conemaugh Indiana 1 2012 2,963 51,080,093 7,80 8 5,594,629 0.12
Conemaugh Indiana 2 2012 3,349 53,881,056 8,121 5,781,428 0.12

Keystone Armstrong 1 2012 17,383 51,332,293 7,653 5,503,604 0.68

Keystone Armstrong 2 2012 12,037 44,348,039 6,281 4,718,662 0.54

Meteorology (weather/transport patterns)

Evidence of source

- receptor relationships between specific emissions sources and high SO 2 values at violating monitors is another important factor in determining the appropriate contributing areas and the appropriate extent of the nonattainment area boun dary. For this factor,

EPA considered data from sites that collected hourly averaged wind measurements including wind direction and speed for 5 years. There is only one ASOS site located within 50 km of the Indiana County monitor. The closest surface si te is the John Murtha Johnstown

- Cambria County Airport located approximately 30 kilometers south

- southeast of the Indiana County monitor. The closest rawinsonde site is located at the Pittsburgh International Airport located approximately 105 km west of t he Indiana County monitor.

One

- minute meteorological wind fields for the Johnstown

- Cambria County Airport site were downloaded and run through AERMOD’s preprocessor AERMINUTE to produce hourly averaged wind fields. This data was then run through Lakes En vironmental’s WRPLOT software to produce wind roses for the Johnstown

- Cambria County Airport ( Figure 7 ). Predominant winds generally ranged from the west over the 2006

- 10 time period. Given this information, EPA is not at this time prepared to conclude t hat large sources in Cambria County (ie. Colver Power Plant, Cambria Cogen, and Ebensburg Cogen) are likely contributing to the violating monitor in Indiana County. We will further address these sources in a future final designations action.28

Figure 7

.

The Commonwealth constructed back trajectories using the NOAA Air Resource Laboratory’s

HYSPLIT trajectory model. Back trajectories were run for exceedances before and after SO 2 controls were installed on the Keystone power plant in Armstrong County, PA. The

Commonwealth used these trajectories to illustrate that while there were significant SO 2 emission reductions at Keystone

, concentrations were only 5 ppb lower after controls were installed and concluded that “[ T ] his illustrates t hat Keystone cannot be considered the sole contributor in either of the violations, even though the trajectories on these two days originate from the region surrounding Keystone. ”

EPA examined the Commonwealth’s s trajectory analysis and constructed its o wn back trajectories for 2010

- 12 using NOAA’s HYSPLIT trajectory model (figure 8)

. Daily emissions

from EPA’s CAMD were also examined to determine the level of power plant operation s at the

time exceedances occurred

. The analyses indicate that emissions from the Keystone power plant in Armstrong County are contributing to exceedances and noncompliance with the 1

- hr SO 2 NAAQS at the Strongstown monitor. EPA acknowledge s and agree s with the contention that Keystone is not the sole contributor to exceedanc e s at Strongstown but it appears the Keystone power plant is contributing to nonattainment in Indiana C ounty and should be included within

the initial nonattainment area based on monitored nonattainment at the monitor in Indiana

C ounty.29

Figure 8.

Geography/topography (mountain ranges or other air basin boundaries)

Figure 8 below depicts elevations and locations of point sources near Indiana County. Indiana County is located east of Pittsburgh in the Allegheny Mountains. The Conemaugh River for ms the southern boundary of the county. Terrain elevations generally rise as you move east culminating along the Chestnut Ridge that marks the eastern boundary of Indiana County. Elevations rise above 600 meters along this ridge with the highest elevatio ns in Pennsylvania located in neighboring Cambria and Somerset Counties.30 Figure 9

.

The Commonwealth included analysis of terrain and approximate release height s (base elevation plus stak e heights) for the Keystone and Homer City power plan ts. The analysis noted that there is intermediate terrain (terrain above the release height) between Keystone and the St ro ngstown
monitor. These , according to the Commonwealth , would likely lead to larger impacts on terrain features west of the Strongsto wn monitor and not at the Strongstown monitor itself

.

There are stack height differences between the Commonwealth’s information and EPA’s

information on stack heights. B ase elevations for both power plants and the Strongstown

moni tor appear to be correct . Stack heights for Keystone units 1 and 2 found in EPA’s Large Power Plant Effluent Study (LAPPES) and the 2005 NEI are listed at 244 m or 800 ft . This gives Keystone an approximate release height of 1,800 ft (stack height plus base elevation)

, which is similar to the elevation of the Strongstown monitor (~1,900 ft). The Commonwealth’s approximate release hei ght for Keystone was 1,573 ft, significantly lower than EPA’s estimate.

If EPA’s estimated release heights for Keystone are correct th e n there w ould be much less if any intermediate terrain between Keystone and the Strongstown monitor. Regardless, the

Commonwealth’s contention that intermediate terrain would s ignificantly lessen the impact of Keystone’s emissions is un likely

. While maximum plant impacts from Keystone would most undoubtedly fall close to the facility, Keystone’s emission s would have ample time to disperse vertically, especially during daytime hours when vertical mixing is enhanced

. Based on the

Commonwealth’s and EPA’s analysis

, exceedances are more likely to occur at the Strongstown

monitor during th ese time s

. Vertical distribution via plume rise and daytime plume mixing

would indicate that emissions from the Keystone power plant in Armstrong County, PA are significantly impac ting the Strongstown monitor.31

Jurisdictional boundaries

EPA provided information about all boundaries considered prior to proposing nonattainment areas and this information can be found in the Pennsylvania TSD as part of the docket on proposed designat ions (78 FR 11124) and is not restated here. EPA originally proposed including all of Indiana County and a portion of Armstrong County (list portions) in the nonattainment area. Although the Commonwealth does not agree that a portion of Armstrong

C ounty should be included, EPA is including the originally proposed portions of Armstrong County in the initial Indiana C ounty N onattainment A rea. Therefore, EPA is designating all of

India na County and Elderton Borough and Plumcreek and South Bend Townships i n Armstrong County PA as the Indiana PA Nonattainment Area.

Conclusion for the Indiana Nonattainment Area

After considering the factors described above, EPA is initially designating all of Indiana C ounty
and a po r ti o n of Armstrong County ( Elderton Borough, Plumcreek Township and South Bend Township ) based on the violating monitor in Indiana County

, as the Indiana PA N onattainment

A rea for the 2010 SO 2 NAAQS

. Sources examined in Cambria and Blair counties have relatively small emissions and are gen erally upwind of the violating monitor, so at this time, these sources and areas are not included in the initial nonattainment area. However, these sources will be addressed in a future final designations action.

The air quality monitor in Indiana Count y shows a violation of the 2010 SO 2 NAAQS, based on

200 9

- 201 1 air quality data and data provide by the Commonwealth. The nearby Keystone power

p lant in neighboring Armstrong County likely contributes to nonattainment in Indiana County as well

. Previous s tudies as di s cussed in the TSD that ac c omp a nied the proposed nonattainment area boundary ( 78 FR 11124 ) have shown that stack tops (of Homer City and Keystone) are at elevations in line with that of the Strongstown monitor in Indiana County. Meteorological data suggests that emissions from large sources west of the monitor likely impact the monitor and

contribute to SO 2 NAAQS violations in Indiana County. Based on the consideration of all the relevant and available information, as described above, EPA beli eves that the boundaries described herein encompass the area that should be initially designated as nonattainment due to causing or contributing to the monitored violation of the 2010 SO 2 NAAQS in Indiana C ounty

.32

Figure 10

.33

Technical Analysis for the Warren Nonattainment Area

In EPA’s 120 day letter, EPA proposed that the initial Warren PA Nonattainment Area consist of Warren County in its entirety. In response to EPA’s 120 day letter, the Commonwealth

recommended that only a portion of Warren County ( the City of Warren and Conewago, Glade

and Pleasant Townships) be included in the nonattainment area and provided an analysis to support their response.

Based on EPA's technical analysis described below, EPA agrees with Pennsylvania’s

recommendation and is initially designating a portion of the county as nonattainment for the

2010 SO 2 NAAQS based on the violating monitors in Warren County. The Warren PA

Nonattainment Area consists of Conewago, Glade and Pleasant Township s and the City of

Warren

.

Air Quality Data

This factor considers the SO 2 air quality monitoring data, including the design value (in ppb)

calculated for the air quality monitor in Warren County based on certified data for the 200 9

- 20 1 1 period

.

The 2010 1

- hour SO 2 design value for the monitor located in Warren County is shown in Table

1 2

.

Table 1 2

. Warren County Monitor Trend : 1

- Hour SO 2 99 th % and Design Value in Parts Per Billion (ppb)

Monitor Name Monitor

Air Quality System ID 99 th % Design

V alue Design

Value

2007 2008 2009 2010 2011 2008

- 10 2009

- 11

Warren 42

- 123

-

0004 153 146 113 109 94 123 105

The Commonwealth indicate d that the design value for 2010

- 2012 was 102 ppb and this was confirmed by EPA.

The Commonwealth examined hourly SO 2 concentrations at the Warren County, PA monitor and

noted exceedances of the 1

- hr SO 2 NAAQS generally occurred during the overnight hours. This was attributed to limited mixing during nocturnal inversions. EPA examined the Warren County, PA monitor’s hou rly SO 2 concentrations from 2009

- 11 and confirmed that peak concentrations and exceedances primarily occur during the overnight hours. This would support that meteorological conditions, namely nocturnal inversions, are contributing to exceedances in

the a rea of the Warren County, PA monitor

.34

Emissions and Emissions

- Related Data

Evidence of SO 2 emissions sources in the vicinity of a violating monitor is an important factor for determining whether a nearby area is contributing to a monitored violation. F or this factor, EPA evaluated county

- level emission s data for SO 2 and any change in SO 2 emitting activities since the date represented by those emissions data

.

Emissions

Table 1 3 shows total emissions of SO 2 in tons per year (tpy) for violating and pot entially contributing counties in and around the Warren Area in Region III emitting greater than 100 tpy

of SO 2 according to the 2008 NEI.

Table 1 3

. SO 2 Emissions in the Warren Nonattainment Area

County Facility

Located in

State ’s Original

Recommen ded

Nonattainment

Area? Facility

Name Total

Facility SO 2 Emissions (tpy) CAMD 2012 (tpy)

Warren , PA Yes United Refining

Warren Plant 1,612

McKean,

PA No American Refining Group/

Bradford 1,479

Chautauqua,

NY No Samuel A.

Carlson Generating

St ation 3,736 215

CAMD Emissions Analysis

Emissions from sources included in EPA’s CAMD database ( http://camddataandmaps.epa.gov/gdm/index.cfm?fusea ction=emissions.wizard ) were reviewed to see if more recent emissions are available for sources near the Warren County, PA monitor. Only the Samuel A. Carlson Generating Station in Chautauqua County, NY reported its SO 2 emissions to CAMD.

Table 1 4

. CAM D 2008

- 1 2 Emissions Summary of SO 2 Emissions in tpy

Facility County Distance * CAMD

2008 CAMD

2009 CAMD

2010 CAMD

2011 CAMD

2012

Samuel A. Chautauqua 28.41 3,736 1,885 1,272 6643 5

Carlson Generating

Station 215 *Distance from Warren County SO 2 monitor in kilometers.

Emissions Controls

Under this factor, EPA considers the existing level of control of emission sources. No SO 2 emission controls were noted on any of the sources within 50 kilometers of the Warren County

monitor.

Meteorology (weather/tra nsport patterns)

Evidence of source

- receptor relationships between specific emissions sources and high SO 2 values at violating monitors is another important factor in determining the appropriate contributing areas and the appropriate extent of the nonatta inment area boundary. For this factor,

EPA considered data from sites that collected hourly averaged wind measurements including wind direction and speed for 5 years. There is only one ASOS site located within 50 km of the Warren County monitor. The clo sest surface site is the Bradford Regional Airport located approximately 44 kilometers east

- southeast of the Warren County monitor. The closest rawinsonde site is located at the Buffalo Niagara International Airport located approximately 130

km north of t he Warren County monitor.

The Commonwealth included a wind analysis that shows wind directions are primarily from the east during hours in which the Warren County, PA monitor exceeds the 1

- hr SO 2 NAAQS. No data was submitted to support this analysis. Pe nnsylvania’s analysis, however, appears to make sense given the primary SO 2 source near the monitor resides to the east.

Geography/topography (mountain ranges or other air basin boundaries)

Warren County is located in northwest Pennsylvania in the state’ s Allegheny Plateau Region. The area is made up of dendritic river valleys cut by the Allegheny River and its tributaries interspersed with higher terrain. Elevations vary from over 600 meters above mean sea level along the plateau to just under 325 mete rs along the Allegheny River as it drains south into Forest County. Higher terrain lies to the west in McKean County with elevations generally decreasing as one moves west towards Lake Erie.

Pennsylvania’s original recommendation noted the influence of l ocal topography on the Warren County monitor. Their analysis examined the monitored wind fields and the timing of exceedances and concluded that local topographically

- induced meteorological conditions, mainly overnight inversions and complex drainage flow s, coupled with a nearby local source contributed to the monitor’s noncompliance with the 1

- hour SO 2 NAAQS. Given this information, EPA is not prepared at this time to conclude that emissions from the Samuel A. Carlson Generating Station in Chautauqua Cou nty, NY nor American Refining

- Bradford in McKean County, PA are likely to contribute to the violating monitor in Warren County, PA. We will further address these sources in a future final designations action. Additional information provided in the36

Common wealth’s recent r esponse further supports the recommendation that only a portion of Warren County which includes the United Refining s ource should be included in the initial

nonattainment Area.

Jurisdictional boundaries

EPA provided information about a ll boundaries considered prior to proposing nonattainment areas and this information can be found in the Pennsylvania TSD as part of the docket on proposed designations (78 FR 11124) and is not restated here. EPA originally proposed including all of Warre n County in the nonattainment area. However additional information provided by the Commonwealth in response to EPA’s proposal demonstrates that the monitor

and sources of concern in this area of the Commonwealth that are most likely impacting the

violatin g monitor are all located within the City of Warren

, Conewago Township, Glade Township and Pleasant Township

. Therefore, EPA is initially designating these portions of

Warren County as the Warren

, PA nonattainment a rea.

Conclusion for the Warren Nonatt ainment Area

After considering the factors described above, EPA is designation the following portions of Warren County as the Warren PA Nonattainment Area: Conewago Township, Glade Township, Pleasant Township and the City of Warren

. The air quality monit or in Warren County shows a

violation of the 2010 SO 2 NAAQS, based on certified 200 9

- 201 1 air quality data and additional data provided by the Commonwealth. Th is monitor indicates that there are high concentrations of

SO 2 emissions in the vicinity

, and bot h m eteorological and topographical data suggest that

emissions from the large source within close proximity of the monitor likely impact the monitor

and contribute to SO 2 NAAQS violations in Warren County. Additional information provided by the Commonweal th also supports this analysis. EP A believes that the boundaries described herein encompass the appropriate initial area that does not meet the 2010 SO 2 NAAQS

. Areas and sources that we are not yet prepared to conclude are contributing to the monitored v iolation are not included in this initial nonattainment area. In a subsequent round of designations we will further address such areas and sources and make final designations decisions for areas that are not currently included in the nonattainment area de signation addressed in this TSD.

Figure 11

.37

EPA’s Area Designations Conclusion for Pennsylvania

EPA has reviewed the information above and is designating based on monitored violations the counties and/or portions of counties liste d in Tab le 1 as nonattainment for the 2010 SO 2 NAAQS. EPA consider ed the factors and information described in this technical support

document . The intended nonattainment area boundaries that EPA describes above are based on the five factors which include: air qu ality data, emissions

- related data, meteorology, geography/topography, and jurisdictional boundaries. Based on the consideration of all the relevant and available information, as described above, EPA believes that the boundaries described herein encompass the area that does not meet (or that contributes to nonattainment in a nearby area ) the 2010 SO 2 NAAQS

. Areas and sources that we are not yet prepared to conclude are contributing to the monitored violation are not included in this initial nonattainment area. In a subsequent round of designations we will further address such areas and sources and make38

final designations decisions for areas that are not currently included in the nonattainment area designation addressed in this TSD.