1 Technical Support Document

Pennsylvania Area Designations For the

2008 Lead National Ambient Air Quality Standard s EPA has revised the level of the primary (health

- based) standard from 1.5 micrograms per cubic meter (μg/m3) to 0.15 μg/m3 measured as tota l suspended particles (TSP). EPA has revised the secondary (welfare

- based) standard to be identical in all respects to the primary standard

.

Pursuant to section 107(d) of the Clean Air Act, EPA must designate as “ nonattainment ”

those areas that violate t he NAAQS and those nearby areas that contribute to violations.

The table below identifies the portion of Beaver County in Pennsylvania that EPA is designating

“nonattainment” for the 200 8 lead national ambient air quality standard (2008 Lead NAAQS)

.

Ta ble 1 . Nonattainment Area for 2011 Designations

Area Pennsylvania

Recommended

Nonattainment

Counties Pennsylvania’s

Recommended

Nonattainment Townships/ Boroughs EPA’s Final

Nonattainment

Counties EPA’s Final

Nonattainment Townships/ Boroughs

Lower Beav er Valley Beaver County

(partial) Potter and

Vanport Beaver County

(partial) Potter, Vanport

and Center

Figure 1. Map of Beaver County containing the Lower Beaver Valley Area in relation to the rest of the Commonwealth of Pennsylvania.2 Technical A nalysis for The Lower Beaver Valley Area

Introduction

Th is technical analysis for The Lower Beaver Valley Area identifies the partial county with a monitor that violate s the 2008 Lead NAAQS and evaluates nearby counties for contributions to

lead concen trations in the area. EPA has evaluated these counties based on the weight of evidence of the following factors recommended in previously issued EPA guidance :

Air quality in potentially included versus excluded areas ; Emissions and emissions

- related da ta in areas potentially included versus excluded from

the nonattainment area , including population data

, growth rates and patterns and emissions controls; Meteorology (weather/transport patter n s) ; Geography/topography (mountain ranges or other air basin bo undaries) ; Jurisdictional boundaries (e.g., counties, air districts, reservations, etc.) ; and Any other relevant information submitted to or collected by EPA.

Figure 2 is a map of the area analyzed showing the location s of air quality monitor s in the area

and the nonattainment area.

Figure 2. Lower Beaver Valley Nonattainment Area and Air Quality Monitor Locations3

On December 17, 2009

, Pennsylvania recommended that part of Beaver County be designated as

nonattainment for the 2008 Lead NAAQS based on air quality data from 2006

- 2008 . Their

recommendation was based on data from FRM or FEM monitor s located in the state. In 2010, EPA designated part of Beaver County nonattainment, consistent with Pennsylvania’s recommendation (75 FR 71033, Nov ember 22, 2010).

Pursuant to the revised network design requirements adopted in the Lead NAAQS final rule (73 FR 66964, Nov ember 12, 2008), Pennsylvania established new lead monitors, including one in Center Township

. Based on EPA's technical analysis described b elow (including data from the new monitors) , EPA is revising the 2010 Nonattainment Designation for parts of Beaver County in Pennsylvania. This county and the townships/boroughs included in the revised nonattainment

area is listed above in Table 1.

Det ailed Assessment

Air Q uality D ata

This factor considers the lead design values (in μg/m 3 ) for air quality monitors in Beaver County

in the Lower Beaver Valley Area and the surrounding area based on data for the 2008

- 2010 period. A monitor’s design va lue indicates whether that monitor attains a specified air quality

standard. The 2008 Lead NAAQS are met at a monitoring site when the identified design value is valid and less than or equal to 0.15 μg/m 3

. A design value is only valid if minimum data

comp leteness criteria are met. A lead design value that meets the NAAQS is generally

considered valid if it encompasses 36 consecutive valid 3

- month site means (specifically for a 3

- year calendar period and the two previous months)

. For this purpose, a 3

- mon th site mean is valid if valid data were obtained for at least 75 percent of the scheduled monitoring days in the 3

- month period. A lead design value that does not meet the NAAQS is considered valid if at least

one 3

- month mean that meets the same 75 perc ent requirement is above the NAAQS. That is, a site does not have to monitor for three full calendar years in order to have a valid violating design value; a site could monitor just three months and still produce a valid (violating) design

value

.

The 200 8 Lead NAAQS design values for Beaver County in the Lower Beaver Valley Area and surrounding area are shown in Table 2 and illustrated in Figure 2

.4

Table 2 . Air Quality Data
County State

Recommended

Nonattainment? Monitor Name Monitor Air Quality System ID Monitor

Location Lead Design

Value,

200 7

- 200 9 (μg/m 3 ) Lead Design

Value,

200 8

- 20 10 (μg/m 3 )

Beaver County Yes (partial) Monaca (Horsehead Corp.) 42

- 007

-

0007 Beaver Valley

Mall, Monaca,

PA 15071 N/A 0.21

Vanport (Horsehead Corp. ) 42

- 007

-

0505 265 River Ave.,

Beaver, PA

15009 0.17 0.17

Potter (Bruce Mansfield) 42

- 007

-

0006 206 Mowry

Rd., Monaca,

PA 15071 N/A Incomplete 1

Monitors in Bold have the highest 2008

- 2010 design value in the respective county.

Beaver County shows a vi olation of the 2008 Lead NAAQS

. Therefore

, some area in this county must be designated nonattainment

. The monitor with the highest 2008

- 2010 design value is located in Center Township. 2 The absence of a violating monitor alone is not a sufficient reason

t o eliminate nearby counties as candidates for nonattainment status. E ach area has been evaluated based on the weight of evidence of the eight factors collectively combined into five like groupings and other relevant information

Emissions and Emissions

- R elated Data

Evidence of lead emissions sources in the vicinity of a violating monitor are an important factor for determining whether a nearby area is contributing to a monitored violation. For this factor, EPA evaluated county level emission data for le ad and any growth in lead emitting activities since the date represented by those emissions data

.

Emissions

Emissions data for industrial were derived from the 2008 National Emissions Inventory,

version 1.5 (NEI08V1 .5 ), which was the most current versio n of the national inventory available

in 20 11when these data were compiled for the designations process. See http://www.epa.gov/ttn/chief/net/2008inventory.html#inventorydoc

. Emissions data for airport sources (there are approximately 20,000 airport facil ities in the U.S. at which leaded aviation gasoline is consumed) were derived from the 2008 NEI, version 1.0. EPA recognize s that we have no information on any emissions increases that may have occurred since 2008 . For example, certain large sources of em issions in or near this area may have installed emission controls or otherwise significantly reduced emissions since 2008

. Some States provided updated information on emissions and emission controls in their comments to EPA. The data provided by Pennsylv ania was the most current emission information available at the time of their

1 This monitor is incomplete for regulatory purposes, but the highest 3

- month average at this location is 0.10 μg/m 3

. 2 The address of the monitor is in Monaca, PA because Center Township does not have its own mailing zipcode and is divided between Monaca and Aliquippa.5

submittal

. For 2008 emissions from Pennsylvania and the 2008 NEI are the same for the lead

sources in Table 3.

Table 3 shows total emissions of lead (given in tons per year) fo r violating and potentially contributing townships/boroughs in and around the Lower Beaver Valley Area and sources emitting (or anticipate d to contribute) greater than 0.1 ton per year of lead according to the state emission inventory (eF.A.C.T.S.) for the years 2007, 2008, and 2009 . See http://www.dep.state.pa.us/dep/efacts/. Facilities that are part of the Lower Beaver Valley Nonattainment Area for the 2008 Lead NAAQS are shown in boldface. The EPA has chosen to accept Pennsylvania’s use of the invento ry

. Figure s 3 and 4 below show the distance between the First Energy Generation Corp/Bruce Mansfield Plant and the Lower Beaver Valley Nonattainment Area. During this second round of designations in 2011, Beaver County has been

reevaluated based on new mo nitoring data to expand the area as discussed in the 2010 Designation TSD for the 2008 Lead NAAQS.

Table 3

. Facility lead emissions greater than 0.1 tons per year
County Facility in State

Recommended

Nonattainment

Area Facility Name and

Location Facil ity

– Total

Air Emissions

2007

- eFacts Pennsylvania’s State inventory (tons per year) Facility

– Total

Air Emissions

2008

- eFacts Pennsylvania’s State inventory (tons per year) Facility

– Total

Air Emissions

2009

- eFacts Pennsylvania’s State inventory ( tons per year)

Beaver County, PA Yes Horsehead Corp./Monaca

Smelter 5.64 5.38 3.825

300 Frankfort Rd.

Beaver County, PA No First Energy Gen. Corp/ Bruce

Mansfield Plant

State Route 168

South 1.20 0.70 0.70

Beaver County, PA No Jewel Acquisition / Midland Factory

12 th St. & Midland

Ave. 0.30 0.10 0.106

Figure 3 . Lower Beaver Valley Nonattainment Area with facility locations within Beaver County, Pennsylvania

.7

Figure 4. Lower Beaver Valley Nonattainment Area and Su rrounding Sources

Population Data , Growth Rates, and P atterns
Table 4 shows the 2008 population for Beaver County being evaluated, as well as the population density for each county in that area. These data help assess the extent to which the concentra tion of human activities in the area and concentration of population

- oriented commercial development may indicate emissions

- based activity contributing to elevated ambient lead levels. This may include ambient lead contributions from activities that would disturb lead that has been8

deposited on the ground or on other surfaces. Re

- entrainment of historically deposited lead is not reflected in the emissions inventory.

Table 4

. Population Data
County State

Recommended

Nonattainment? 2008

Population 2008

Po pulation Density (pop/sq mi) Population

Change

2000

- 2008 Population

% Change

2000

- 2008

Beaver County,

PA Yes (partial)

172,476 389

- 8,639

- 5% Source of data: U.S. Census Bureau estimates for 2008 ( h ttp://www.census.gov/popest/datasets.html ) and estimation

of the area of U.S. Counties

Beaver County has a declining population trend between 2000 and 2008. EPA has considered the growth rate of population density and related commercial development for this area and does

not believe that it affects the nonattainment boundary

.

Emissions Controls

Under this factor, the existing level of control of emission sources is taken into consideration. The emissions data used by EPA in this technical analysis an d provided in Table 3 represent s emissions levels taking into account any control strategies implemented in the Lower Beaver Valley Nonattainment Area before 2007 on stationary sources.

Horsehead Corporation is a zinc processing facility which produces high purity zinc oxide and high grade zinc metal using a two step distillation process. There are two sources responsible for the majority of the lead emissions from the facility: the sintering line and the electrothermic

furnace line. Raw materials con sisting of crude zinc oxide and other secondary materials are fed to a sintering machine. Under high temperatures, air is drawn through the materials, resulting in fused chunks that become feedstock for the electrothermic furnaces. Various impurities (su ch as lead) are volatilized during the processing. Emissions from this process are controlled by a baghouse. According to the company, 95 % of the lead emissions from the furnaces are emitted through baghouses, and only 5% escapes as fugitive emissions.

Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service instruments and other meteorological monitoring sites in the area. Wind direction and wind speed data is from 1960

- 1992 Solar and Meteorologica l Surface Observation Network information issued jointly by the U.S. Department of Commerce: National Climatic Data Center and the U.S. Department of Energy: National Renewable Energy Laboratory. This data is summarized in Figure 5 and Table

5 , below. This data may provide evidence of the potential for lead emissions sources located upwind of a violating monitor to contribute to ambient lead levels at the violation location.9

Figure 5

. Wind directions summarized by season for Beaver County, PA

Tab le 5

. Top two prevailing wind directions by season for Beaver County, PA

Season Wind direction Percent of

wind at that

direction

Winter West, Southwest 25

Winter West, Northwest 22 Spring West, Northwest 20 Spring West, Southwest 16

Summer West, Sout hwest 20

Summer South, Southwest 18

Autumn West, Southwest 19

Autumn West, Northwest 18

As shown in the graph in Figure 5 and Table 5 , the prevailing surface winds were predominantly from the west, northwest and west, southwest for all four seasons.

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

The geography/topography analysis evaluates the physical features of the land that might have an effect on the air shed and, therefore, on the distribution of lead over the Lower Beav er Valley

Nonattainment Area.10

The Lower Beaver Valley Nonattainment Area does not have any geographical or topographical

barr iers significantly limiting air pollution transport within its air shed. Therefore, this factor did not play a significant role in determining the nonattainment boundary.

Jurisdictional boundaries

Existing jurisdictional boundaries may be helpful in articulating a boundary for purposes of nonattainment designations, and for purposes of carrying out the governmental responsibili ties of planning for attainment of the lead NAAQS and implementing control measures. These existing boundaries may include an existing nonattainment or maintenance area boundary, a county or township boundary, a metropolitan area boundary, an air manageme nt district, or an urban planning boundary established for coordinating business development or transportation activities.

The Lower Beaver Valley Nonattainment Area is constructed using the township boundaries within Beaver County.

Conclusion

After co nsidering the factors described above, EPA has determined that it is appropriate to include the portion of Beaver County, PA listed in Table 1 in the Lower Beaver Valley Nonattainment Area for the 2008 Lead NAAQS.

The air quality monitor s in Beaver Coun ty show a violation of the 2008 Lead NAAQS, based on

2008

- 2010 air quality data and support the expansion of the previously designated Lower Beaver Valley Nonattainment Area to include Center Township

. EPA is modifying Pennsylvania’s recommendation by a dding Center Township to the Lower Beaver Valley Nonattainment Area. EPA’s nonattainment area includes Center Township, Potter Township

, and Vanport Township located within Beaver County. Center Township has been added to Pennsylvania’s recommended Lower Beaver Valley Area because of the violating new monitor located within this township.

EPA is revising the 2010 designation, rather than making a separate designation (which would trigger a separate SIP process) , because we believe the prior designation did not fully capture the area that does not meet the standard but we do not believe there are sources contributing to nonattainment in the newly designated area. Rather, we believe the source within the area designated in 2010 is the cause of nonattainm ent extending into the newly designated area, and the SIP process for attaining the standard in the previously designated area should also serve to attain the standard in the newly designated area. In these circumstances, revising the boundaries of the pr eviously designated area is appropriate. Based on its consideration of all the relevant, available information, as described above, EPA believes that the boundaries described herein encompass the entire area that does not meet (or that contributes to ambi ent air quality in a nearby area that does not meet) the 2008 Lead NAAQS.11

Definition of important terms used in this document:

1) Designated “nonattainment” area

– an area which EPA has determined, based on a State

recommendation and/or on the technic al analysis included in this document, has violated the 2008 Lead NAAQS, based on the most recent three years of quality assured air quality monitoring data from 2008

- 2010 including at least one valid three

- month site mean above the

level of the 2008 Lead NAAQS, or that contributes to a violation in a nearby area.

2) Designated “unclassifiable/attainment” area

– an area which EPA has determined does not contribute to a violation of the 2008 Lead NAAQS in a nearby area and either: (1) meets the

2008 Lead NAAQS, based on the most recent three years of quality assured air quality monitoring data from 2008

- 2010 including 36 consecutive valid three

- month site means (including the last two months of 2007), or (2) has no monitors or has incomplete air quality

m onitoring data for 2008

- 2010 but has no violations of the 2008 Lead NAAQS.

3) Designated “unclassifiable” area

– an area which EPA has determined cannot be classified on the basis of available information as meeting or violating the 2008 Lead NAAQS, based on the most recent three years of quality assured air quality monitoring data from 2008

- 2010, but for which available monitoring data from the same or a recent period indicate a significant likelihood that the area may be violating the 2008 Lead NAAQS.

4 ) Recommended nonattainment area

– an area a State or Tribe has recommended to EPA be designated as nonattainment.

5 ) Violating monitor

– an ambient air monitor whose valid design value exceed s 0.15 micrograms per cubic meter (ug/m3) . As described in Appe ndix R of 40 CFR part 50, a violation

can be based on either Pb

- TSP or Pb

- PM10 data and only three months of data are necessary to produce a valid violating design value.

6 ) 1978 Lead NAAQS

– 1.5 μg/m 3 , National Ambient Air Quality Standard for lead

prom ulgated in 1978. Based on Pb

- TSP indicator and averaged over a calendar quarter.

7 ) 2008 Lead NAAQS

- 0.15 μg/m 3 , National Ambient Air Quality Standard for lead promulgated in 2008. Based on Pb

- TSP indicator and a three

- month rol ling average. Pb

- PM10

data may be used in limited instances, including to show nonattainment.