## UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IV

Technical Support Document EPA’s Notice of Proposed Rulemaking

For Approval and Promulgation of Air Quality Implementation Plans; Ohio, Kentucky, and Indiana; Cincinnati - Hamilton Non attainment Area; Determination of Attainment of the 1997 Annual Fine Particulate Standards

May 20112

A. BACKGROUND On July 18, 1997 (62 FR 36852), EPA established an annual PM 2.5 NAAQS at 15.0 μg/m 3 based on a 3 - ye ar average of annual mean PM 2.5 concentrations. At that time, EPA also established a 24 - hour standard of 65 μg/m 3 (today ’s action does not address the 24 - hour standard). See 40 CFR 50.7. On January 5, 2005 (70 FR 944), EPA published its air quality designations and classifications for the 1997 PM 2.5 NAAQS based upon air quality monitoring data from those monitors for calendar years 2001

–2003. These designations became effective on April 5, 2005. The Cincinnati Area was designated nonattainment for the 1997 PM 2.5 NAAQS. See 40 CFR 81. 336 (Ohio), 40 CFR 81. 318 (Kentucky ), and 40 CFR 81. 315 (Indiana) . On October 17, 2006 (71 FR 61144), EPA retained the annual PM 2.5 NAAQS at 15.0 micrograms per cubic meter (μg/m 3 ) based on a 3 - ye ar average of annual mean PM 2.5 concentrations . On November 13, 2009, EPA clarified the designations for the NAAQS promulgated in 1997, stating that the Cincinnati Area was designated as nonattainment for the annual standard. B. EPA REQUIREMENTS A nonattainment area for the 1997 PM 2.5 NAAQS is determined to have attaining data when the design value 1 for the annual standard meet s the requirements s tipulated in 40 CFR P art 50, section 50. 13 as follows: The annual primary

and secondary

PM 2.5 standards are met when the annual arithmetic mean concentration, as determined in accordance with appendix N of this part, is less than or equal to 15.0 μg/m 3

. Upon determination by

EPA that an area designated nonattainment for the PM 2.5 NAAQS has attained the standard, 40 CFR section 51.1004(c) provides that the requirement for such area to submit attainment demonstrations and associated reasonably available control measures, reasonable further progress plans, contingency measures, and other planning SIPs related to attainment of the PM 2.5 NAAQS shall b e suspended until the area is redesignated to attainment, at which time the requirement no longer appl ies. However , if EPA subsequently determines that the area has violated the PM 2.5 NAAQS, the requirement to submit such plans is reinstated. C. EPA’S ANALYSIS OF MONITORED DATA

1 Design values are the metrics that are compared to the NAAQS levels to determine attainment. The annual design value is calculated as the 3 - year average of annual means (referred to as the “annual standard design value ”). (See 40 CFR part 50 Appendix N.)3

EPA’s determination that the Cincinnati nonattainment Area is attaining the 1997 PM 2.5 NAAQS is based upon complete, quality assured, qual ity

controlled and certified ambient air monitoring data for the 200 7 - 200 9 period, as measured by Federal reference method, Federal equivalent method, or Approved Regional Method monitors described in 40 CFR Part 50 , Appendix N. The monitors and data used to determine the 2007 - 2009 annual PM 2.5 design value for the Cincinnati nonattainment area are included in the t able below. Annual PM 2.5 Design Value s for Monitors in the Cincinnati Nonattainment Area Location AQS site ID 200 7 98 th P ercentile 200 8

9 8 th P ercentile 200 9

98 th P ercentile 200 7 - 200 9

Design Value Verity 39 - 017 - 0003 15.4 13.8 12.8 14.0 Sacred Heart School 39 - 017 - 0016 14.9 13.8 13.1 13.9 Batavia 39 - 025 - 0022 14.0 11.7 11.0 12.3 Sycamore 39 - 061 - 0006 14.6 12.5 12.1 13.1 Carthage 39 - 061 - 0014 16.6 15.1 13.4 15.0 Taft 39 - 061 - 0040 15.1 12.6 12.7 13.5 Lo wer Price Hill 39 - 061 - 0042 15.9 14.4 13.7 14.7 Norwood 39 - 061 - 7001 15.1 13.7 13.0 13.9 Murray Rd 39 - 061 - 8001 16.1 14.4 13.4 14.6 Lebanon 39 - 165 - 0007 14.0 11.9 11.7 12.5 NKU 21 - 037 - 3002 14.4 11.8 11.3 12.5 Covington 21 - 117 - 0007 14.2 12.0 11.0 12.4 Inaddition to the sites listed in the table above, two sites, Scarlet Oaks School (39 - 061 - 0043) and Hook Field Airport (39 - 017 - 1004), did not operate for the entire three - ye ar period from 2007 - 2 009 . The first of these two sites , Scarlet Oaks School , discontinued operation after the fourth quarter of 2008. The letter approving the Ohio Monitoring Network , dated January 5, 2010 , approved the discontinuation of this monitor and stated that Ohio’s monitoring network satisfies the applicable monito ring network requirements for PM 2.5 . The Scarlet Oaks Schoo l site monitored an average concentration of 14.8 μg/m 3 in 2007, and an annual average concentration in 2008 of 13.3 μg/m 3

. The average concentration for the most recent three year s of available data, i.e., 2006 - 2008 , was 14.2 μg/m 3

. This average concentration is consistent with attainment of the NAAQS . The second site, Hook Field Airport , discontinued operation after the fourth quarter of 200 7 . Region 5 documented the approval of the closure of the Hook Field Airport site in early 2010 in a letter dated December 21, 2010, to the Hamilton County Department of Environmental Services. The site was shut - down due to safety issues in which the monitor was located. The Hook Field Airport site monitored an annual average concentration of 14.6 μg/m 3 for 2007 . The average concentration for the most recent three years of available data, i.e., 2005 - 2007 , was 15.0 μg/m 3

. This average concentration is consistent with attainment of the NAAQS.4

The other monitor in the Cincinnati Area that did not collect complete data for 2007 - 2009 began sampling well after the beginning of this period. The NKU site, site number 21 - 037 - 3002 , was not operational until August 1, 2007 . For this site, the average of concentrations in the last quarter of 200 7 was 1 4 .4 μg/m 3 , the annual average of concentrations in 200 8 was 11.8 μg/m 3 , and the annual average of concentrations in 2009 was 1 1 . 3 μg/m 3 . The average concentration using available data in 2007 to indicate 2007 concentrations and using complete data in 2008 and 2009 is 12.5 μg/m 3

. The monitors in the Cincinnati Area that collected complete data for 2007 - 2009 have average concentrations that are all consistent with attainment of the 1997 annual PM 2.5 NAAQS. Determinations of attainment are based on three years of complete, quality- assured data. Nevertheless, any

such assessment should consider additional quality- assured data, to the extent that quality- assured data exist. Inaccordance with Appendix N and standard EPA practice, th e review of data is based o n the three most recent years of complete data, generally 2007 - 2009 . Appendix N does not provide for examining partial years of data, because various seasons of the ye ar reflect various influences on PM 2.5 concentrations, and a partial year’s data may not be representative of values that would be determined from a full year’s data set. Nevertheless, EPA examined data from the first half of 20 10 . The complete year has not been certified; therefore, the data are not considered complete for 2010. All of the 2 008 - 2010 design values are below the 15.0 μg/m 3 , except for the Murray Road site in Cincinnati. The Murray Road site has a preliminary

2008 - 2010 design value of 15.1 μg/m 3 ; however, the site was shut down in February of the first quarter of 2010 due to safety issues. Region 5 approved the shut down in a letter dated December 21, 2010. The partial first quarter of 2010 data before the monitor shut down showed the only

data above the NAAQS for the 2008 - 2010 period. The 2008 design value was 14.4 μg/m 3 and the 2009 design value was 13.4 μg/m 3

. Approval was granted for the site to be shut down because the Carthage Fire site registered a higher design value and is located approximately

a mile from the Murray

Road site. A comparison of the 2007 - 2009 data showed the sites were well correlated with each other. The available data for 20 10 are consistent with the finding, based on 2007 - 2009 data, that the Cincinnati Area is attaining the 1997 annual PM 2.5 NAAQS . On the basis of this review, EPA has concluded that this area has met and continues to me et the 1997 PM 2.5 NAAQS . D . CONCLUSIONS AND RECOMMENDED AGENCY ACTION Q uality assured, quality

controlled, and certified ambient air monitoring data for 200 7 - 200 9 show s that the design value for the Cincinnati PM 2.5 nonattainment Area is 15 . 0 μg/m 3

. Because this value is less than or equal the 1997 annual PM 2.5 NAAQS of 1 5 μg/m 3 , the area has monitored attainment for this NAAQS. I recommend the Cincinnati Area be determined to have attaining data for the 1997 annual PM 2.5 NAAQS.