## UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION S III, IV, and V

Technical Support Document

EPA’s Notice of Proposed Rulemaking

For Approval and Promulgation of Air Quality Plans; Determination of Attainment of the

1997 Fine Partic u l a t e Standard

January 20112 Technical Support Document

I. INTRODUCTION..............................................................................

... ....... ... . 3

II. CLEAN AIR ACT REQUIREMENTS FOR FINE PARTIC U L ATE (PM 2.5 ) ATTAINMENT. 3

A. P M 2.5 Attainment Requirements ......................................................

....... ...... ...3

B. Determin ation of Attainment

................................................................... . ....... .4

III. MONITORING NETWORK ................................................

. ............ ... ..... .........5

IV. LAWRENCE COUNTY HOSPITAL MONITORING SITE

....... ...... .............. ...... ........ 6

V. EPA’S ANALYSIS ..............................

............................... ..... ..................... .. 6

A. Analysis of Air Quality Data

................................................ ..... ..................... 6 B. Addressing Missing Data

......................................................... ..... ................. 6 C. Additional Analysis

..................................................................... ..... .......... 1 4 D. Air Quality in 2010.....................................................................

............ .... 1 4

VI. CONCLUSION...........................................................................

..... ......... .... 1 4

APPENDIX A Annual Means for the Huntington

- Ashland Area PM 2.5 FRM monitors

... ...... ........... 1 63

I. INTRODUCTION

On April 1, 2010, Ohio requested that EPA determine that multiple areas, including the Huntington

- Ashland Area, are attaining the 1997 annual fine partic u l at e (PM 2.5 ) National Ambient Air Quality Standard (NAAQS). In addition, pursuant to 179(c)(1) of the Clean Air Act, EPA is required to

make a determination about the status of this area as of its attainment date. This technical support document specifically addresses the Huntington

- Ashland PM 2.5 nonattainment area , including portions in West Virginia, Kentucky, and Ohio ( hereafter referred to as “the Huntington

- Ashland Area ” or “the

Area” ) . In this technical support document, EPA provides information supporting : the proposed

determination that the Huntington

- Ashland Area has attained the 1997 annual PM 2.5 NAAQS (hereafter

referred to as “the annual PM 2.5 NAAQS” or “the sta ndard”) and that the area has attained the 1997

annual PM 2.5 NAAQS by its applicable attainment date of April 5, 2010.

In this technical support document, EPA:

- summarizes the statutory and policy requirements for PM 2.5 nonattainment area SI Ps and EPA’s policy concerning attainment.

- provides a description of th e air quality monitoring network for the Huntington

- Ashland Area

PM 2.5 nonattainment area

- provides a description of the air quality monitoring network for the Huntington

- Ashland Area

- d escribes the Lawrence County Hospital (LCH) monitoring site, and provides an explanation

for monitor shutdown;

- describes our detailed analysis of our proposed determination of attainment , including our analysis of the air quality data, and the methodology used for substituting for missing data;

- describes air quality trends in the Huntington

- Ashland Area

- summarizes our conclusions on the proposed determination of attainment with respect to EPA requirements.

II. CLEAN AIR ACT REQUIREMENTS FOR FINE P ARTICLE (PM 2.5 ) ATTAINMENT

A. PM 2.5 Attainment Requirements

In 1997, EPA established the health

- based NAAQS for PM 2.5 , setting an annual stan dard at 15.0 micrograms per cubic meter (ug/m 3 ) based on a 3

- year average of annual mean PM 2.5 concentrations,

and a 24

- hour standard of 65 ug/m 3 based on a 3

- year average of the 98th percentile of 24

- hour

concentrations. EPA established the standards bas ed on significant evidence and numerous health studies demonstrating that serious health effects are associated with exposures to particulate matter.

On January 5, 2005, (70 FR 944) EPA finalized its air quality designations and classifications

across the country with respect to the 1997 PM 2.5 standard . These designations became effective on April 5, 2005. The Huntington

- Ashland Area was designated nonattainment for the 1997 annual PM 2.5 NAAQS ( See 40 CFR 81. 349 (West Virginia), 40 CFR 81. 318 (Kentuck y), and 40 CFR 81. 336 (Ohio ).

These designations triggered the Clean Air Act’s requirements under section 172(c), which4

requires the submission of an attainment plan for each designated nonattainment area. EPA’s PM 2.5 implementation rule, published on April 25, 2007 (72 Fed. Reg. 20586) specifies that states must submit attainment plans for their nonattainment areas to the EPA by no later than three years from the effective date of designation, that is, by April 5, 2008. E PA’s PM 2.5 implementation rul e outlines the SIP requirements for the attainment plan, which includes among other things, the submission of an attainment demonstration showing the air

- quality improvements expected to result from national and local control measures, an analysis of reaso nably available control measures (RACM), including all reasonably available control technology (RACT), reasonable further progress plan, and contingency

measures. EPA’s implementation rule also set s the attainment date in these areas as April 5, 2010, and

the determination woul d be based on data from 2007

- 20 09 (72 FR 20600).

The s tates of West Virginia, Kentucky, and Ohio

, are subject to these requirements since several

counties in the s tate s are located in a PM 2.5 nonattainment area. T he Huntington

- Ashl and Area is

comp o sed of some or all of the following counties in West Virginia, Kentucky, and Ohio : Cabell,

Mason (part) and Wayne Counties in West Virginia; Boyd and Lawrence (part) Counties in Kentucky;

and Adams (part) , Gallia (part) , Lawrence, and Sci oto Counties in Ohio

.

B. Determination of Attainment

Under EPA regulations at 40 CFR 50.7 , t he annual primary and secondary PM 2.5 standards are met when the annual arithmetic mean concentration, as determined in accordance with 40 CFR part 50, Appendix N, is less than or equal to 15.0 ug/m 3

.

Data handling conventions and computations necessary for determining whether areas have met

the PM 2.5 NAAQS, including requirements for data completeness, are listed in Appendix N of 40 CFR Part 50. A year meets data completeness requirements when at least 75 percent of the scheduled sampling days for each quarter have valid data. The use of less than complete data is subject to the approval of EPA, which may consider f actors such as monitoring site closures/move s, monitoring diligence, and nearby concentrations in determining whether to use such data.

If this proposed determination of attainment is made final, EPA will have met its statutory obligation pursuant to section 179(c)(1) of the Clean Air Act (CAA) to make a determination based on the Area’s air quality data as of the attainment date whether the area attained the standard by that date. Additionally, as a result of such determination, the requirements for Kentucky, Ohio or West Virginia to

submit an attainment demonstration and associated RACM, a RFP plan, contingency measures, and any other planning SIPs related to attainment of the 1997 annual PM 2.5 NAAQS within the Huntington

Ashland Area would be suspended until such time as: a) the area is redesi gnated to attainment, at which time the requirements would no longer apply; or, b) EPA determines that the area has violated the

annual PM 2.5 NAAQS, at which time, the area would be required to submit such plans. See 40 CFR 51.1004(c).

A determination o f attainment do es not shield an area from other required actions such as New Source Review (NSR), conformity and emission inventory requirements, and provisions to address pollution transport, which would require emission reductions at sources or other typ es of emission5

activities contributing significantly to nonattainment in other areas or states, or interfering with

maintenance in those areas.

Determinations as to whether individual areas have attained the PM 2.5 standards and thus qualify for the applic ation of a determination of attainment are being made in the context of rulemakings for individual areas. This Technical Support Document (TSD) provides an explanation of EPA’s analysis

used to determine whether t he Huntington

- Ashland Area has attained th e annual PM 2.5 standard by the applicable attainment date.

III. MONITORING NETWORK

The Huntington

- Ashland Area currently has three air monitoring locations ; one each in West Virginia, Kentucky, and Ohio

. West Virginia also has a collocated monitor in p lace at the site f or quality assurance purposes. The primary monitor, and not the collocated monitor, is used to determine compliance with the PM 2.5 NAAQS. Since the coll o cated quality assurance monitor takes many fewer readings than the primary monitor, its average annual values may be unrepresentatively high even if only a few high values are recorded. (See 40 CFR Part 50, Appendix N, 3(d)(1). Two monitoring

locations for Ohio are listed in Table 1 due to the LCH monitor shut

- down and Ironton DOT start

- up during the 2007

- 2009 time period. Table 1 shows the monitor design values (DVs) ( i.e., the 3

- year average of annual mean PM 2.5 concentrations) for the years 200 7

- 2009. The area DV is the high est annual mean measured for a federal reference method ( FR M ) monitor that had complete data in a

county.

Table 1.

— 2007

- 2009 Design Values for the 1997 Annual PM 2.5 NAAQS for the Huntington

- Ashland Area M onitors in

Micrograms per Cubic Meter (ug/m 3 ).

Site Name County Site Number Annual Average

Concentration (μ g/m 3 ) Huntington Cabell 54

- 011

- 0006 14.3 1

Ashland Primary ( F IVCO) Boyd 21

- 019

- 0017 12.4

Lawrence County Hospital Lawrence 39

- 087

- 0010 13.3 2

1 West Virginia has a collocated monitor in place at the same site for quality assurance purposes. The primary monitor, and

not the collocated moni tor, is used to determine compliance with the PM 2.5 NAAQS. Since the collocated monitor takes fewer readings than the primary monitor, its average annual values may be unrepresentatively high

. See 40 CFR Part 50, Appendix N, 3(d)(1).

2 Data from the Lawre nce County Hospital and Ironton DOT sites were incomplete due to shut

- down of the Lawrence County Hospital site and startup of the Ironton DOT site in February 2008.6 Ironton DOT Lawrence 39

- 087

- 0012 12.2 3

EPA meets annually with each state to discuss any pro blems or issues co ncerning state s ’ air monitoring data and/or network. In addition, EPA and the s tates communicate many times during the year so that issues can be addressed as they show up. EPA regulations require states to submit annual network plans to their respective Regions. These plans outline the current networks and any proposed changes in the upcoming 18 months. Regions 3, 4, and 5 have been able to approve these plans due to the quality of the West Virginia, Kentucky, and Ohio monitoring networks.

IV. LAWRENCE COUNTY HOSPITAL MONITORING SITE

The LCH monitor operated until February 11, 2008 , when monitoring was discontinued permanently at the site due to the building demolition. Because the monitor at this location c ould not be replaced , a new site in this c ounty was established at the Ironton DOT starting when monitoring at the

LCH ended. As a result, t he Ironton DOT monitor did not obtain any data for 2007 and did not obtain complete data for the first quarter of 2008. Nevertheless, the available data for the remainder of 2008

and all of 2009 indicate attainment at this monitor.

As discussed in greater detail below, t he monitors in Lawrence County were the only monitors in

the Huntington

- Ashland Area without valid attaining DVs for 2007

- 2009 due to inc omplete data. This monitor historically measured lower concentrations than other monitors in the Area, including, for example, the monitor in Cabell County, West Virginia.

V. EPA’S ANALYSIS

A. Analysis of Air Quality Data

EPA has reviewed the ambient a ir monitoring data for PM 2.5 , consistent with the requirements contained in 40 CFR part 50 and recorded in the EPA Air Quality System database for the Huntington

Ashland Area from 200 7 through the present time. Currently all monitors are measuring concent rations averaging well below the annual standard of 15.0 ug/m 3 . The highest DV for the most recent 3 years, 2007

- 2009, for the Huntington

- Ashland Area is 14. 3 ug/m 3

, based on monitoring data collected in West Virginia at the Huntington monitor

. All 3

- yea r averages of the annual mean PM 2.5 concentrations are below the NAAQS from 200 7

- 200 9

.

In order to determine whether the NAAQS has been attained for the LCH monitor

, EPA has applied a recently developed procedure to address the missing data, and determ ine valid DV s for th e monitor for the annual standard for 2007

- 2009. EPA’s procedure is described in the following section.

3 The Lawrence County Hospital Site was shut

- down in February 2008. The Ironton DOT site began operation in 2008 after the Lawrence County Hospital Site ceased monitoring.7

B. Addressing Missing Data

Additional analysis was necessary for the LCH monitor ( site number 39

- 087

- 0010) because this

monitor is no longer operating (due to building demolition) but recorded a violation in the most recent three year period in which it collected complete data. An objective statistical method was used to
determine if this monitor would likely have met the NAAQS in su bsequent time periods.

The general concept behind the statistical method is to establish a linear regression relationship

between the monitor of interest and another “comparison monitor ” in the nonattainment area based on

data obtained when the monitor of interest was still operating . The method then estimates

concentrations at the monitor of interest for the period after monitor shutdown by applying a linear regression to the more recently observed concentrations at the other monitor. The results are checked with an additional statistical technique, known as bootstrapping, to verify if the conclusion of attainment

is correct.

The monitor of interest in this analysis is the LCH monitor

. Th is site ceased monitoring in February 2008 and had an incompl ete DV of 1 2

. 9 μg/m 3 for 200 7

- 2008. The goal of this methodology is to appropriately fill in the missing data from the quarters 1

- 4 of 2008, and quarters 1

- 4 of 2009 to judge whether th is location would likely have monitored attainment of the NAAQS had th e monitor

continued to operate

. The Huntington

- Ashland Area has two monitoring locations with complete data

for 2007

- 2009

, listed in Table 1 above, both of which are similar enough to warrant comparison to the

LCH monitor.

Criteria to be met

EPA establi shed criteria to assure that the DV for the LCH monitor in the Huntington

- Ashland

Area

, as estimated by the method

, was robust enough to allow consideration of the results in a weight of

evidence decision. EPA established criteria both for the operating p eriod of the comparison monitor and for the number of days of samples that the comparison monitor and the LCH monitor have in common. EPA has not established bright lines or specific requirements for determining DV s for monitor s with less than complete da ta.

Operating period

In order to provide satisfactory concentration estimates for the LCH monitor for the period after

the monitor shut down

, comparison monitors in the Huntington

- Ashland Area would need to have operated from well before from February 2008 to the end of 2009 . Operation for a substantial period before February 2008 is necessary to support a robust regression relationship with concentrations at the

LCH monitor , and operation from February 2008 to the end of 2009 is necessary to support

c oncentration estimates for this period.

Paired samples

Pairs of sample data for the LCH monitor and comparison monitors from the most recent 20

- quarter period of operation of the LCH monitor were used. Comparison monitors were required to have8

at leas t 100 historical sample pairs in common with the target monitor during this period. When there were more than 100 pairs in the 20

- quarter period

, all available pairs were used. In addition to the 100 pairs over the 20

- quarters, comparison monitors were r equired to have at least 20 paired days of data in

common with the LCH monitor for each quarter (adding together the number of days in a given calendar quarter [Q1, Q2, Q3, or Q4] across the various years in the 20

- quarter period).

Both comparison monitor s , Ashland Primary and Huntington, met the eligibility criteria of 100 pairs over the 20

- quarters, and at least 20 paired days of data in common with the LCH monitor for each calendar quarter.

Method for determining DV s

Step 1

– Organize data and perfor m linear regression(s) between the LCH monitor a nd the comparison

monitors

.

For both the Ashland Primary and the Huntington monitor s, a ll the available paired data within

the 5

- year period described above w ere used to develop a linear regression expressin g concentrations at

the LCH monitor in relation to concentrations at the comparison monitor

.

Step 2

– Select candidate monitor

The Huntington

- Ashland Area has 2 monitors which could have been used as comp arison

monitor s , Ashland Primary and the Hunting ton

. The follow ing steps were used to select the comparison

monitor.

1) C omparison monitors were placed into order of highest correlation (highest r

- squared in the linear regression) of concentrations with concentrations at the LCH monitor

. The compar ison monitor showing the highest correlation of concentrations with concentrations at the LCH monitor was used first.

2) Using the regression equation relating concentrations at the LCH monitor and the comparison monitor, estimates of the 24

- hour average concentrations at the LCH monitor were made for each day

after this monitor was shut down that the monitor otherwise would have been scheduled to measure concentrations, except that no estimate was made if the comparison monitor had no valid measurement. The estimates were combined with any reported data at the LCH monitor i n the recent 3

- year period and the data capture rates were computed for each originally incomplete quarter.

3) If performing the process in #2 results in all 12 quarters at the LCH m onitor having at least 75 percent of scheduled values, the comparison monitor was selected for use in the remaining steps. If 75 percent of

the scheduled values for the LCH monitor were not obtained, the steps in #2 were repeated for the next

best correlat ed comparison monitor . This process was repeated until the LCH monitor had at least 75 percent of the number of values expected under its original operating schedule

.

Step 3

– DV Computed9

The 3

- year DV was calculated using the actual observations at the LCH monitor and the regression

- based estimates of daily co ncentrations. The resulting DV for the LCH monitor was 13.3 μg/m 3 , which is below the annual PM 2.5 NAAQS

.

Step 4

– Statistical confidence of a DV below the NAAQS checked

In order to show that the re is a minimal probability that the actual DV (had the LCH monitor operated more days) was above the annual PM 2.5 NAAQS

, further analysis was performed as follows:

(a) Residuals were calculated from the regression. (b) A bootstrap analysis was performe d, repeating the regression

- based substitution in Step 2 but adding to each estimated 24

- hour value that substitutes for a missing scheduled monitored value a plus or minus residual that has been randomly drawn (with replacement) from the pool of regressio n residuals. This step randomly applies real residuals from the linear regression to the imputed current

- period target values. (c) Repeat (b) for a total of 1000 runs. (d) For each of the 1000 bootstrap trials, the 3

- year DV was calculated. This pr ovide s a pseudo confidence interval for the partially imputed current

- period DV for the target

. (e) Since none of the 1000 runs resulted in a DV above the annual PM 2.5 NAAQS, the LCH

monitor w as considered to have met the annual PM 2.5 NAAQS.

Determi ning the DV for Lawrence County Hospital (AQS ID: 39

- 087

- 0010 )

The analysis described above was performed to estimate concentrations at the LCH monitor

. The results of the regressions can be found in Table 2 . T he LCH monitor is identified in this table as Site A. The comparison monitor s in this table are all identified in this table as Site B. The Ashland Primary monitor ( AQS ID: 21

- 019

- 0017 ) had the highest correlation with the LCH monitor and met the operating period and paired data eligibility crite ria for being the comparison monitor . The results of the regression between the LCH monitor and the Ashland Primary monitor are shown in Figure 1

. Estimates for the missing data for quarters 1 thru 4 of 2008 and for quarters 1 thru 4 of 2009 for the

LCH monitor were made. These quarters were the quarters with less than 75 percent data capture. As a result of filling in the missing data, the LCH monitor now had 3 2 , 30, 31 , 3 0 values for quarters 1 thru 4 for 2008, respectively, and 30, 30, 2 7 , 31 values for quarters 1 thru 4 of 2009 , respectively . A DV of

1 3

. 3  g/m 3 was calculated for the LCH monitor when the missing data was filled in , as shown in Figure

2

.

The statistical confidence of the DV was checked using the method outlined in Step 4 above.

The results of the 1000 bootstrap trials provided the following results : 243 DVs ) of 13. 2 μg/m 3

, 223

DVs of 1 3

. 3 μg/m 3

, 177 DVs of 1 3 .1 μg/m 3

, 157 DVs of 13.4 μg/m 3

, 81 DVs of 13. 0 μg/m 3

, 61 DVs of

13. 5 μg/m 3

, 21 DVs of 13. 6 μg/m 3

, 19 DVs of 12.9 μg/m 3

, 8 DV s of 13. 7 μg/m 3

, 6 DVs of 12.8 μg/m 3

, 2

DVs of 12.7 μg/m 3 , and 2 DVs of 13.8 μg/m 3

. None of the 1000 bootstrapping trials resulted in a violating DV, which provides statistical confidence that the air quality at the LCH monitor is below the

annual PM 2.5 N AAQS.10Table 2. Correlation and data capture for monitors used to determine a DV for Lawrence County Hospital site.Figure 1 Concentrations at Lawrence County Hospital (site 390870010, labeled “v_a”) compared to concentrations at Ashland (site 210190017 , labeled “v_b”).

The linear relationship between the two monitors is: C oncentration at Lawrence County Hospital = 2.29 3135 + 0.882184 *

concentration at Ashland. The correlation coefficient was 0. 86384.13

Figure 2 . Results for Lawrence County Hospital site after filling in missing data

for all quarters of 2008, and all quarters of 200914

C. Additional Analysis

Additional statistical analysis was performed for the LCH monitor using a different

compa rison monitor . EPA re

- ran the analysis using data from the Huntington monitor (site number 54

- 011

- 0006)

, a monitor that is similarly correlated with the LCH monitor as the Ashland Primary monitor

. The results of the analysis using the Huntington monitor as the comparison monitor produced an

estimated 2007

- 2009 DV at the LCH of 13.1 μg/m 3 , which is also below the NAAQS of 15.0 ug/m 3

. That is, the concentration estimates provided by the method described here in indicate a DV at LCH that

is below the annual PM 2.5 NAAQS, regardless of which area monitor is used as the basis for the

estimates.

D. Air Quality in 2010

The states have submitted monitoring data for 2010. EPA examined 2008 to 2010 data as

a n indication of whether the area continues to a ttain the standard. Table 3 shows the average concentration at each of the sites in the Huntington

- Ashland Area. All sites have average concentrations well below the standard, with a verage values ranging from 12.2 to 13. 1 μg/m 3 . Therefore, EPA believes

that 2008 to 2010 data, interpreted in conjunction with data from 2007 to 2009, supports a determination that the Huntington

- Ashland Area is attaining the annual PM 2.5 NAAQS.

Table 3

. — 20 008

- 2010 a nnual average PM 2.5 concentrations for the Huntington

- As hland Area monitors in m icrograms per

c ubic m eter (ug/m 3 ).

Site Name County Site Number Annual Average

Concentration (μg/m 3 ) Huntington 4 Cabell 54

- 011

- 0006 13. 1

Ashland Primary ( F IVCO) Boyd 21

- 019

- 0017 11.4

Ironton DOT Lawrence 39

- 087

- 0012 12. 2

VI. CONCL USION

EPA is proposing to determine that the Huntington

- Ashland Area has attained the annual

1997 PM 2.5 NAAQS by its attainment date of April 5, 2010.

4 West Virginia has a collocated monitor in place at the same site for quality assurance purposes. The primary monitor, and not the collocated monitor, is used to determin e compliance with the PM 2.5 NAAQS. Since the collocated monitor takes fewer readings than the primary monitor, its average annual values may be unrepresentatively high

. See 40 CFR Part 50, Appendix N, 3(d)(1).15 EPA has reviewed the ambient air monitoring data for PM 2.5 , consistent with the requirements containe d in 40 CFR part 50 and recorded in the EPA Air Quality System database for the Huntington

- Ashland Area

. The 3

- year averages of the annual mean PM 2.5 concentrations continue to be below the NAAQS of 15.0 ug/m 3

.

EPA has concluded that use of less than complete data from the LCH monitoring site is warranted for determining attainment of the NAAQS. The States of West Virginia, Kentucky, and Ohio have been diligent in the number and placement of PM 2.5 monitors in the nonattainment area . The

monitor at LCH was shut down due to a planned building demolition and could not be replaced. In light of such facts, EPA employed a procedure using a statistical method to estimate concentrations at the

LCH monitor for the remainder of the time period at issue; and, th e resulting analysis supports a finding

of attainment of the annual PM 2.5 NAAQS at this location.

As provided in 40 CFR 51.1004(c), if EPA finalizes this determination, it would suspend the requirements for this area to submit attainment demonstrations

, reasonably available control measures, reasonable further progress plans, and contingency measures related to attainment of the 1997 annual

PM 2.5 NAAQS so long as the A rea continues to attain the 1997 annual PM 2.5 NAAQS.16 A p pendix A

Annual Means for the Huntington

- Ashland Area PM 2.5 FRM monitors