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### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION III 1650 Arch Street Philadelphia, Pennsylvania 19103 

### NOV 0 7 Z01Z Technical Support Document Regarding Ozone Monitoring Data; Pennsylvania; Determinations ofAttainment ofthe 1997 8-Hour Ozone Standard for the Pittsburgh-Bea y_er Valley Moderate Nonattainment Area

## 71/~t/ikl JA..-u.r Maria 

### A. Pino. Senior Air Quality Planning Specialist Office ofAir Program Planning File (\ Donna Mastro, Acting Associate Directol

# ~**~** Office ofAir Program Planning This document provides a technical review ofthe air quality monitoring data used to support the proposed determination by the Environmental Protection Agency (EPA) that the PittsburghBeaver Valley 8-hour ozone nonattainment area (the Pittsburgh Area) has attained the 1997 ozone national ambient air quality standard (NAAQS).
A. BACKGROUND The Pittsburgh Area includes Allegheny, Armstrong, Beaver, Butler, Fayette, Washington, and Westmoreland Counties in Pennsylvania. The Pittsburgh Area was originally classified under the more general subpart 1 nonattainment provisions ofthe Clean Air Act (CAA) for the 1997 8- hour ozone NAAQS. However, on April27, 2012, EPA finalized revisions to the 2004 Phase 1 Implemeptation Rule for the 1997 8-hour ozone NAAQS that specified requirements to meet the 1997 ozone NAAQS. The revisions to the Phase 1Implementation Rule are EPA's response to a December 22, 2006 decision by the United States Court ofAppeals for the District ofColumbia Circuit. See South CoastAir Quality Management Dist. v. EPA, 

### 472 F.3d 882 (D.C. Cir. 2006). As a result ofthat rulemaking action, classifications for 16 ozone nonattainment areas originally classified under subpart 1

### for the 1997 ozone NAAQS, including the Pittsburgh Area, were revised under subpart 2. The Pittsburgh Area was reclassified as a moderate nonattainment area for the 1997 ozone NAAQS. (77 FR 28424, May 14, 2012). The moderate area attainment data was June 15, 2010.B. EVALUATION OF AIR QUALITY MONITORING DATA I. Data Requirements The criteria for determining ifan area is attaining the 1997 8-hour ozone NAAQS are set out in 40 CPR 50.10 and appendix I. The determination is based on the three mostrecent, complete, consecutive calendar years ofquality assured air quality monitoring data at all ozone monitoring sites in the area. To attain this standard, the annual fourth-high daily maximum 8-hour ozone concentrations measured at each monitor averaged over the three-year period (the monitoring site's ozone design value) must not exceed the ozone standard. The level ofthe 1997 8-hour NAAQS for ozone is 0.08 parts per million (ppm). Based on an ozone data rounding convention described 

### in 40 CPRpart 50, appendix I, the 1997 8-hour standard is met ifozone design value is 0.084 ppm (84 ppb) or lower. When the design value is less than or equal to 0.084 ppm at each monitoring site within the area, the area meets the NAAQS. The data must be collected and quality-assured in accordance with 40 CPRpart 58, and must be recorded in EPA's Air Quality System (AQS). The data supporting attainment ofthe standard must be complete in accordance with•40 CPRpart 50, appendix I. The data completeness requirement is met when the average percent ofdays with valid ambient monitoring data is greater than 90%, and no single year has less than 75% data completeness. For the Pittsburgh Area, the ozone season extends from the beginning ofApril through the end of October. A complete ozone season consists of214 monitoring days.
II. Certified Air Quality Monitoring Data, 2007- 2011 EPAhas determined that the ozone monitoring network for the Pittsburgh Area is adequate. 1 First, the number ofmonitors in the Pittsburgh Area meets the minimum regulatory requirements given in 40 CPRpart 58, appendix D, section 4.1. Second, the monitoring network in place is in accordance with Pennsylvania's most recent annual monitoring network plan approved by EPA, as required by 40 CPR 58.10. During the 2007-2009,2008-2010, and 2009-2011 monitoring periods, the Pittsburgh Area had inplace a total of 13 ozone monitoring sites whose data was eligible for comparison to the 1997 8-hour ozone NAAQS. The Commonwealth ofPennsylvania submitted complete, quality assured air quality monitoring data into AQS, and EPA concurred on Pennsylvania's data. Attached are AQS reports containing 8-hour ozone data for the Pittsburgh Area for the 2007 to 2011 ozone monitoring seasons. Tables 1, 2, and 3, below, summarizes the data found in those reports.

1 EPA approved the Commonwealth ofPennsylvania's August 4, 2011 annual ambient monitoring netWork plan in a December 6, 2011 letter from Shawn M. Garvin, Regional Administrator ofEPA Region ill, to Michael L. Krancer, Secretary ofthe Pennsylvania Department ofEnvironmental Protection.

2T bl 1 2007 2009 P"tt b I A 8 H 0 a e : 

## - • s ureu rea - our zone D " VI &DtC esagn a ues a a I t omp1 e eness 4th Highest Value Percent Completeness (ppm) 2007-2009 (valid monitored days/required days) County Site ID Design Value 2007 2008 2009 (ppm) 2007 2008 2009 2007-2009 average Allegheny 420030008 0.083 0.079 0.069 0.077 99 100 98 99 Allegheny 420030010 0.081 0.074 0
.067 0
.074 100 97 99 99 Allegheny 420030067 0.077 0.075 0.069 0.073 94 99 100 98 Allegheny 420031005 0.086 0.085 0.077 0.082 94 100 98 97 Armstrong 420050001 0.083 0.078 0.071 0
.077 100 100 100 100 Beaver 420070002 0.080 0.073 0.066 0
.073 96 97 97 97 Beaver 420070005 0.072 0.075 0
.068 0.071 99 95 97 97 Beaver 420070014 0.077 0.074 0.068 0
.073 100 100 100 100 Washington 421250005 0.077 0.071 0.068 0.072 99 99 100 99 Washington 421250200 0.073 0.069 0.063 0
.068 100 100 99 

## roo Washington 421255001 0.075 0
.077 0.065 0.072 100 89 97 95 Westmoreland 421290006 0.079 0.072 0.064 0.071 100 100 100 100 Westmoreland 421290008 0.077 0.075 0.065 0.072 99 100 97 99 T bl 2 2008 2010 p· b I A 8 H 0

a e : 

## - atts ureh rea - our zone D . VI &D C esien a ues ata ompJ eteness 4th Highest Value Percent Completeness (ppm) 2008-2010 (valid monitored days I required days) Design County Site ID Value 2008 2009 2010 (ppm) 2008 2009 2010 2008-2010 average Allegheny 420030008 0.079 0.069 0.080 0
.076 100 98 96 98 Allegheny 420030010 0
.074 0.067 0.074 0.071 97 99 92 96 Allegheny 420030067 0.075 0.069 0.078 0.074 99 100 98 99 Allegheny 420031005 0.085 0.077 0.083 0
.08 1 100 98 99 99 Armstrong 420050001 0.078 0.071 0
.079 0.076 100 100 100 100 Beaver 420070002 0.073 0.066 0
.075 0
.07 1 97 97 97 97 Beaver 420070005 0.075 0.068 0.077 0.073 95 97 97 96 Beaver 420070014 0.074 0.068 0.073 0.071 100 100 86 95 Washington 421250005 0.071 0.068 0.072 0
.070 99 100 99 99 Washington 421250200 0.069 0.063 0
.073 0
.068 100 99 99 99 Washington 421255001 0.077 0.065 0.071 0
.071 89 97 97 94 ; Westmoreland 421290006 0.072 0.064 0.070 0.0
. 68 100 100 98 99 Westmoreland 421290008 0.075 0.065 0.076 0.072 100 97 97 98



### 3T bl 3 2009 2011 p· b I A 8 H 0 a e 

# . - Itts urg11 rea - our 

# . zone D' VI &DtC es1gn a ues a a I t omp1e eness 

# I 4th Highest Value 2009-2011 Percent Completeness (ppm) County Site ID Design (valid monitored days I required days) Value 2009 2010 2011 (ppm) 2009 2010 2011 2009-2011 average Allegheny 420030008 0.069 0.080 0.074 0.074 98 96 100 Allegheny 420030010 0.067 0.074 0.074 0.071 99 92 93 Allegheny 420030067 0.069 0.078 0.078 0.075 100 98 100 Allegheny 420031005 0.077 0.083 0.080 0
.080 98 99 100 Armstrong 420050001 0.071 0.079 0.069 0.073 100 100 100 Beaver 420070002 0.066 0.075 0.068 0.069 97 97 98 Beaver 420070005 0.068 0.077 0
.071 0
.072 97 . 97 99 Beaver 420070014 0.068 0.073 0.072 0
.071 100 86 97 Washington 421250005 0.068 0.072 0.068 0
.069 100 99 99 Washington 421250200 0.063 0.073 0.069 0.068 99 99 99 Washington 421255001 0.065 0.071 0.071 0.069 97 97 95 Westmoreland 421290006 0.064 0.070 0.072 0
.068 100 98 100 Westmoreland 421290008 0.065 0.076 0.068 0
.069 97 97 100 As shown in Tables 1, 2, and 3, above, al12007-2009, 2008-2010, and 2009-2011 8-hour ozone design values for the Pittsburgh Area are 0.084 ppm or less. In addition, all monitors meet the completeness requirements ofan average percent ofdays with valid ambient monitoring data greater than 90%, and no single year has less than 75%. Therefore, the Pittsburgh Area meets the 1997 8

-hour ozone NAAQS, considering 2007-2009,2008-2010, and 2009-2011 data.
III. Preliminary Air Quality Monitoring Data, 2012 Preliminary 2012 data reviewed by EPA is consistent with continued attainment. According to 40 CFR Part 58, states are required to submit air quality monitoring data for each calendar quarter no later than 90 days after the end ofthe quarter. States are required to certify that data for a given year is quality assured and accurate by May 1 ofthe following year. Therefore, Pennsylvania has until May 1, 2013 to certify data for the 2012 ozone season.
Attachments: 98 95 99 99 100 97 98 

### 94 99 99 96 99 98

- EPA AQS Quick Look Report (AMP450), Report Request ID: 820199, dated December 28, 2010, containing 2007- 2009 ozone air quality data for Pittsburgh Area.

- EPA AQS Quick Look Report (AMP450), Report Request ID: 990457, dated May 8, 2012, containing 2009-2011 ozone air quality data for Pittsburgh Area.

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