UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION III 1650 Arch Street Philadelphia, Pennsylvania 19103 - 2029
SUBJECT: Determination of Failure to Attain by 2005 and Determination of

Attainment by 2008 for the 1 - Hour Ozone National Ambie nt Air Quality Standards in the Baltimore Nonattainment Area in Maryland [EPA - R03 - OAR - 2011 - 0680] FROM: Christopher Cripps, Project Officer /s/ January 26 , 2012 Office of Air Program Planning TO: File for Docket EPA - R03 - OAR - 2011 - 0680 T HRU: Cristina Fernandez, Associate Director /s/

Office of Air Program Planning Throughout this document, “we,” “us,” and “our” refer to the Environmental Protection Agency (EPA). I. For w hat Action s ha s this Document been prepared? EPA is proposi ng two separate and independent determinations for the Baltimore 1 - hour severe ozone nonattainment area (hereafter “the Baltimore area”) : A. Proposed Determination of Failure to Attain by Applicable Attainment Date: For the Baltimore area, EPA is pro posing to determine that the area did not attain the 1 - hour ozone NAAQS by the applicable attainment date, November 15, 2005. This proposed determination is based upon complete, quality - assured and certified air quality monitoring data for the 2003 throug h 2005 ozone seasons. B. Proposed Determination of Current Attainment: EPA is also proposing to determine that the Baltimore area is currently attaining the 1 - hour ozone NAAQS, based upon complete, quality - assured and certified ambient air monitoring da ta showing the area has monitored attainment of the 1 - hour ozone NAAQS for the most recent three year period 2008 - 2010. Preliminary data that is available for 2011 indicate that the Baltimore area continues to attain the standard. EPA’s review shows tha t the area has monitored attainment continuously since the 2006 - 2008 monitoring period. If this proposed determination is made final,2

the requirement for the State of Maryland to submit contingency measures related to attainment of the 1 - hour ozone NAAQS in the Baltimore area shall be suspended. II. What is the Background for these Proposed Actions? A. What are the Geographical Boundaries of the Baltimore A rea? The Baltimore area consists of Anne Arundel, Baltimore, Carroll, Harford, and Howard Co unties and the City of Baltimore in Maryland. B. What is the History of the Ozone Designations and Classifications for the Baltimore 1 - hour Ozone Nonattainment Area? Pursuant to provisions of the CAA, EPA must establish NAAQS for certain widespread po llutants that cause or contribute to air pollution that is reasonably anticipated to endanger public health or welfare (sections 108 and 109 of the CAA). In 1979, EPA promulgated the 1 - hour ozone standard of 0.12 parts per million (ppm) (44 FR 8202, Febru ary 8, 1979). For ease of communication, EPA may informally report ozone concentrations in parts per billion (ppb) where one - thousand ppb equals one ppm. Thus, 0.12 ppm becomes 120 ppb or up to 124 ppb when rounding is considered. (Rounding is further di scussed in section IV.B of this document.) EPA first designated the Baltimore area as an ozone nonattainment area in 1978. See , 43 FR 8962 at 9001, March 3, 1978. 1 Under the 1990 Amendments to the CAA, the CAA designated “by operation of law” as nonatt ainment each area of the country that was already designated nonattainment for the 1 - hour ozone NAAQS. The Baltimore area was one such pre amendment ozone nonattainment area so designated nonattainment for ozone. The CAA as amended in 1990 further classi fied “by operation of law” each ozone nonattainment area as marginal, moderate, serious, severe, or extreme depending on the severity of the area's air quality problem. See , CAA sections 107(d)(1)(C) and 181(a). The control requirements and date by wh ich attainment is to be achieved vary with an area's classification. Marginal areas are subject to the fewest mandated control requirements and had the earliest attainment date, November 15, 1993, while severe and extreme areas are subject to more stringe nt planning requirements and are provided more time to attain the standard. Based upon air quality monitoring data, the Baltimore area was classified as “severe - 15” with a statutory attainment date of November 15, 2005. See , 56 FR 56694, November 6, 1 991. C. What Is the Background of 1 - Hour Ozone Anti - Backsliding Requirements in the Transition to the 1997 8 - Hour Ozone Rule? 1 This action designated the Metropolitan Baltimore Intrastate Air Quality Control Region ( See , 40 CFR 81.28), which has the same boundaries as the Baltimore 1 - hour ozone nonattainment area, as nonattainment for “photochemical oxidants.” The term “photochemical oxidants” was replaced by “ozone” in a February 8, 1979 final rule (44 FR 8202 at 8220).3

On July 18, 1997 (62 FR 38856), EPA promulgated a new, more protective standard for ozone based on an 8 - hour average concen tration (the “1997 8 - hour ozone NAAQS”). In an April 30, 2004 final rule (69 FR 23858), EPA designated and classified most areas of the country under the 1997 8 - hour ozone NAAQS promulgated in 40 CFR 50.10. We designated the Baltimore area as nonattainme nt for the 1997 8 - hour ozone NAAQS. This 8 - hour ozone nonattainment area is composed of the same five counties and city as the 1 - hour ozone nonattainment area. We classified this area as moderate under the 1997 8 - hour ozone NAAQS. At the time of designa tion, the same area remained in nonattainment for the 1 - hour standard. On April 30, 2004 (69 FR 23951), EPA issued a final rule entitled “Final Rule To Implement the 8 - Hour Ozone National Ambient Air Quality Standard

— Phase 1” (the “Phase 1 Implementa tion Rule”). Among other actions, this rule revoked the 1 - hour ozone NAAQS in the Baltimore area (as well as in most other areas of the country), effective June 15, 2005. See , 40 CFR 50.9(b); 69 FR 23951 at 23996; and 70 FR 44470, August 3, 2005. Altho ugh EPA revoked the 1 - hour ozone standard, eight - hour ozone nonattainment areas remain subject to certain 1 - hour anti - backsliding requirements based on their 1 - hour ozone classification. Initially, in our rules to address the transition from the 1 - hour to the eight - hour ozone standard, EPA did not include contingency measures or the section 185 fee program among the measures retained as 1 - hour ozone anti - backsliding requirements. 2 However, on December 23, 2006, the United States Court of Appeals for the Dis trict of Columbia Circuit determined that EPA should not have excluded these requirements from its anti - backsliding requirements. South Coast Air Quality Management District v. EPA (SCAQMD v. EPA) , 472 F.3d 882 (D.C. Cir. 2006) rehearing denied 489 F.3d 1 245 (clarifying that the vacatur was limited to the issues on which the court granted the petitions for review). Thus, the Court vacated the provisions that excluded these requirements. As a result, States must continue to meet the obligations for 1 - hour ozone NAAQS contingency measures and, for Severe and Extreme areas, major source fee programs. EPA has issued a proposed rule that would remove the vacated provisions of 40 CFR 51.905(e), and that addresses contingency measures for failure to attain or ma ke reasonable further progress toward attainment of the 1 - hour standard. See 74 FR 2936, January 16, 2009 (proposed rule); 74 FR 7027, February 12, 2009 (notice of public hearing and extension of comment period). III. What is the Rationale for and Effe ct of these Proposed Determinations for the Baltimore Area? A. What is the Rationale for the Proposed Determination of Failure to Attain by Applicable Attainment Date?

2 Final Rule to Implement the 8 - Hour Ozone National Ambient Air Quality Standard -- Phase 1, 69 FR 23951 (April 30, 2004).4

After revocation of the 1 - hour ozone standard, EPA must continue to provide a mechan ism to give effect to the 1 - hour anti - backsliding requirements. See , SCAQMD v. EPA , 47 F.3d 882, at 903. In keeping with this responsibility with respect to 1 - hour anti - backsliding contingency measures and section 185 fee programs, EPA proposes to determi ne that the Baltimore area failed to attain the 1 - hour ozone standard by its applicable attainment date . Consistent with 40 CFR 51.905(e)(2) and the decision in SCAQMD v. EPA , upon revocation of the 1 - hour ozone NAAQS for an area, EPA is no longer obligat ed to determine whether an area has attained the 1 - hour NAAQS by its applicable deadline, except insofar as it relates to effectuating the anti - backsliding requirements that are specifically retained . EPA’s proposed determination here

– that the area did not attain the 1 - hour ozone standard by the November 15, 2005 deadline (based on data for 2003 - 2005) is linked solely to two required 1 - hour ozone anti backsliding measures: i.e., 1 - hour contingency measures for failure to attain under section 172(c)(9), and fee programs under sections 182(d)(3), 182(f) and 185. A final determination of failure to attain by the area’s 2005 1 - hour ozone attainment date will not result in reclassification of the area under the revoked 1 - hour standard . As a severe 1 - hour ozone nonattainment area, the Baltimore area is not subject to reclassification for the 1 - hour ozone standard, and in any event EPA is no longer required to reclassify any area to a higher classification for the 1 - hour ozone NAAQS based upon a determinati on that the area failed to attain that NAAQS by its attainment date. See , 40 CFR 51.905(e)(2)(i)(B). EPA’s proposed determination that the area failed to attain the 1 - hour ozone standard by its applicable date, if finalized, would bear on the area’s o bligations with respect to two 1 - hour ozone anti - backsliding requirements whose implementation would be triggered by a finding of failure to attain by the applicable attainment date: section 172(c)(9) contingency measures for failure to attain, and sectio ns 182(d)(3) ad 185 major stationary source fee programs. B. What is the Rationale for the Proposed Determination of Current Attainment and the Proposed Suspension of the Contingency Measures Related to Attainment of the 1 - hour Ozone NAAQS? Subpart 2 of part D of Title I of the CAA contains various air quality planning and SIP submission requirements for ozone nonattainment areas. We believe that one can reasonably interpret provisions regarding RFP and attainment demonstrations, along with certain other related provisions, so as not to require SIP submissions if an ozone nonattainment area subject to those requirements is monitoring attainment of the 1 - hour ozone NAAQS as demonstrated with three years, of complete, quality - assured, air quality monit oring data. EPA has interpreted the general provision of subpart 1 of part D of Title I (sections 171 and 172) so as not to require the submission of SIP revisions concerning RFP, attainment demonstrations, or contingency measures. As explained in a memo randum dated May 10, 1995 from John S. Seitz, Director, Office of Air Quality Planning and Standards to the Regional Air Division Directors, entitled “Reasonable Further Progress, Attainment Demonstration, and Related Requirements for Ozone Nonattainment A reas Meeting the Ozone National Ambient Air Quality Standard,” (Clean Data Policy) EPA believes we can appropriately interpret the more specific RFP, attainment demonstration and related provisions of subpart 2 in the same manner. ( See , Sierra Club v. EPA,5

99 F.3d 1551 (10 th Cir. 1996)). Under this policy, if EPA determines through rulemaking that the a 1 - hour ozone nonattainment area is meeting the 1 - hour ozone NAAQS, the requirements for a state to submit and have an approved SIP for the following non attainment area plan elements can be suspended : (1) an attainment demonstration, and related components such as reasonably available control measures (RACM); (2) a RFP demonstration; and (3) contingency measures for failure to attain or to make reasonab le further progress. These requirements would be suspended based on a finding of attainment of the 1 - hour ozone NAAQS. The U.S. Court of Appeals for the District of Columbia Circuit upheld the provisions of 40 CFR 51.918, which codified the Clean Da ta Policy. Previously Courts of Appeals for several other Circuits upheld the Clean Data Policy under the 1 - hour standard. See NRDC v. EPA, 571 F.3d 1245 (DC Cir. 2009); Sierra Club v. EPA, 99 F. 3d 1551 (10th Cir.1996); Sierra Club v. EPA, 375 F.3d 537( 7th Cir. 2004) and Our Children’s Earth Foundation v. EPA, No. 04

– 73032 (9thCir. June 28, 2005) (memorandum opinion). See the discussion and rulemakings cited in the Phase 2 Rule, 70 FR 71644 - 71646 (November 29, 2005). C. What is the Status of the Mary land SIP Regarding the 1 - Hour Ozone Anti - backsliding Requirement for Contingency Measures? With respect to the 1 - hour ozone anti - backsliding requirement for contingency measures, EPA has previously approved the State of Maryland’s 1 - hour ozone attainment demonstration, RACM and RFP plans, and RFP contingency measures for Baltimore. See , 66 FR 49108 (Sept. 26, 2001), 66 FR 54666 (Oct. 30, 2001) , 68 FR 61103 (October 27, 2003), 68 FR 75191 (December 30, 2003), 69 FR 7133 (February 13, 2004). See , also 64 FR 70397 (December 16, 1999 ) , 68 FR 40861 (July 9, 2003), 65 FR 4638 (July 28, 2000), 66 FR 36964 (July 16, 2001), and September 7, 2001 (66 FR 44760 (September 7, 2001) supplemental notices of proposed rulemakings for the October 30, 2001 final rule . While EPA did not approve contingency measures for failure to attain the 1 - hour ozone NAAQS in the Baltimore area, reductions from measures that were not relied upon in the attainment demonstration provided more reductions than necessary to serve the pu rpose of contingency measures for this area. 1 . How Is the 2005 Contingency Requirement Calculated? C ontingency measure s for failure to attain aims to provide for a 3 percent reduction in emissions . The amount of reductions required is computed from the same baseline as is used for computing reductions needed for reasonable further progress (RFP) (or as RFP was termed for the 1 - hour ozone NAAQS, rate - of - progress (ROP)) for the attainment year. . See , “General Preamble for the Implementation of Titl e I of the Clean Air Act Amendments of 1990,” 57 FR6

13498 at 13511, April 16, 1992 . I n the case of the Baltimore area , this is 3 percent of its2005 attainment year ROP; this equates to 8.23 tons per day ( TPD ) of volatile organic compounds ( VOC ) or 13.77 T PD of nitrogen oxides ( NOx ) . This is computed as 3 percent of the “1990 Inventory Adjusted to 2005 . ” How the “1990 Inventory Adjusted to 2005” is calculated as discussed in detail in section I I I. A and Tables 3 and 4 of the December 30, 2003 (68 FR 75191 at 75192 - 75193 ), notice of proposed rulemaking (NPR) cited above . The 3 percent contingency requirement is calculated as follows: Table 1 Summary of Contingency Requirement Precursor VOC NOx 1990 Inventory Adjusted to 2005 (in TPD) * 274.43 458.86 Tim es 3 % (3/100) x 0.03 x 0.03 Minimum Contingency Requirement (in TPD) = 8.23 13.77 *From Tables 3 and 4 of the December 30, 2003 NPR (68 FR 75191 at 75192 - 75193). The determination of the “1990 Inventory Adjusted to 2005” is discussed in detail in th e rulemaking notices associated with the approval of the 1 - hour ozone NAAQS RFP plan for the Baltimore area. These notices are the December 30, 2003, notice of proposed rulemaking (68 FR 75191) and the February 13, 2004, final rulemaking notice (69 FR 713 3). These are appended as Appendix B to this document for the convenience of the reader. 2 . Does the Maryland SIP Provide for Additional reductions after 2005? The approved 1 - hour ozone RFP for the Baltimore area projected levels of VOC and NOx emis sions of 221.53 and 344.47 TPD by November 15, 2005. See , Table 7 in the proposed rule (68 FR 75191 at 75194, December 30, 2003) for the February 13, 2004 (69 FR 7133) final action on the RFP plan for the 1 - hour ozone NAAQS. This 1 - hour ozone RFP plan se t motor vehicle emissions budgets (MVEBs) of 55.5 TPD of VOC and 144.5 TPD of NOx. See , Table 2 in the December 30, 2003 (68 FR 75191 at 75192) notice of proposed rulemaking. The approved RFP plan for the 1997 8 - hour ozone NAAQS projected levels of VO C and NOx emissions as 219.25 and 277.50 TPD, respectively, by December 31, 2008. See , Table 5 in the proposed rule (75 FR 958 at 961, January 7, 2010) for the June 4, 2010 final action (75 FR 31709) on the RFP plan for the 1997 8 - hour ozone NAAQS. This plan set MVEBs of 41.2 TPD of VOC and 106.8 TPD of NOx. See , Table 10 in the January 7, 2010 (75 FR 958 at 963) notice of proposed rulemaking. Also appended for the convenience of the reader in Appendix B of this document are the rulemaking notices for t he RFP plan for the Baltimore area under the 1997 8 - hour ozone NAAQS. These are the January 7, 2010, notice of proposed rulemaking (75 FR 958) and the June 4, 2010 final rulemaking notice (75 FR 31709). An RFP / ROP includes a target level of emissions ne eded to meet the RFP requirement and a demonstration that the projected levels of emissions in the area by the RFP deadline date will be equal to or less than the target level after accounting for growth. See , 57 FR 13498 at 13507 - 13508, April 16, 1992, a nd, for specifics relating to the Baltimore area, see the notices of proposed rulemaking cited in the preceding paragraph . While the baseline for the target levels7

for 2005 and 2008 are different, the projected levels of emissions are more comparable beca use they represent projections of actual emissions levels for some year in the future after the baseline year. 3 Both the 2008 and 2005 use consistent methods for projecting growth in emissions - related activities after the baseline years and most important ly use the same emissions factor model, MOBILE6, for developing emissions factors for on - road or highway mobiles sources. As a severe 1 - our ozone nonattainment area the ROP plan included target levels of VOC and NOx emissions for November 15, 2005 which was the Baltimore area’s attainment date for the 1 - hour ozone NAAQS. As a moderate 1997 8 - hour ozone nonattainment area, the RFP plan for the Baltimore area included target levels of VOC and NOx emissions for December 31, 2008. EPA has approved the ROP a nd RFP plans for 2005 and 2008; see , 69 FR 7133, February 13, 2004 and 75 FR 31709, June 4, 2010, respectively. The following t able compares the projected emissions levels for November 15, 2005 and December 31, 2008: Table 2 Comparison of the Projecte d Emissions Levels for November 15, 2005 and December 31, 2008. Portion of the Emissions Inventory All Emissions On - Road Mobile Sources Only Precursor VOC (TPD) NOx

(TPD) VOC

(TPD) NOx

(TPD) RFP Projected Emissions as of 11/15/2005* 221.53 344.47 55 .5 144.5 RFP Projected Emissions as of 12/31/2008 219.25 277.50 41.2 106.8 Difference 2.05 66.97 14.3 37.7 Notes on Sources: *Tables 2 and 7 in 68 FR 75191, December 30, 2003 **Tables 5 and in 75 FR 958, January 7, 2010. The SIP for the Baltimo re area provided for reductions in emissions from motor vehicles of 14.3 TPD of VOC and 37.7 TPD of NOx after November 15, 2005 but by December 31, 2008, and reductions in total emissions of 2.05 TPD of VOC and 66.97 TPD of NOx emissions after 2005 but by December 31, 2008. The 1 - hour attainment demonstration did not rely upon any of these reductions after November 15, 2005. As noted in section IIIC.1 of this document, the contingency measure requirement for failure to attain for the Baltimore area under the 1

– hour ozone NAAQS was 8.23 TPD of VOC or 13.77 TPD of NOx . The Maryland SIP for the Baltimore area provided for over 65 TPD of NOx emission reductions after November 15, 2005 but by December 31, 2008 , of which a third would satisfy the contingency me asure requirement. EPA can conclude that the Maryland SIP provided for sufficient emission reductions to fulfill the 3 percent contingency requirement and has provided enough emission reductions after November 15, 2005 to attain the 1 - hour ozone NAAQS , as evi de nced by attainment of the 1 - hour ozone standard by 2008 and continued attainment thereafter. These additional reductions after 2005 helped bring the Baltimore area into attainment of the 1 - 3 The baseline year for the 2005 ROP plan was 1990; the baseline year for the 2008 RFP plan was 20 02. The baseline year emissions inventories are based on actual levels of emissions.8

hour ozone NAAQS by 2008 . D . What would be the Effect s of these Proposed Determinations for the Baltimore Area? As noted above, EPA is also proposing a separate and independent 1 - hour ozone determination -- that the Baltimore area currently attains the 1 - hour ozone standard, based on complete, quality - assu red and certified ozone data for 2008 - 2010, and preliminary data available for 2011. 4 If this determination is finalized, then even if EPA finalizes its proposed determination that the area failed to attain the 1 - hour ozone standard by the 2005 deadline, it will not result in any 1 - hour ozone contingency measure obligations for the area. Under EPA’s “Clean Data Policy” interpretation discussed in section III.B of this document , which was articulated first for the 1 - hour standard and later codified for th e 8 - hour ozone standard (40 CFR 51.918), a determination of attainment suspends obligations to make submissions for attainment - related requirements (including contingency measures) for that standard. See , for example, determination of 1 - hour ozone attai nment for Baton Rouge, 75 FR 6570 (February 10, 2010). With respect to the 1 - hour ozone anti - backsliding requirement for penalty fees, section 182(d)(3) requires SIPs to include provisions required by section 185. Section 185 requires 1 - hour ozone SIP s for severe areas to provide that, if the area has failed to attain by the attainment date, each major stationary source of ozone precursors located in the area must begin paying a fee to the State . Thus a final determination of failure to attain by the area’s 1 - hour attainment date would trigger the 1 - hour anti - backsliding obligation to implement the penalty fee program under section 182(d)(3) 182(f) and 185, unless that obligation is terminated. IV. How Does EPA Compute W hether an Area Complies with the 1 - Hour Ozone NAAQS? A. What is the L evel and F orm of the 1 - hour O zone NAAQS ? The relevant regulation, 40 CFR 50.9(a), states the following regarding the 1 - hour ozone NAAQS: (1) The level of the national 1 - hour primary and secondary NAAQS for ozo ne is 0.12 parts per million; and (2) The 1 - hour ozone NAAQS “ is attained when the expected number of days per calendar year with maximum hourly average concentrations above 0.12 parts per million is equal to or less than 1, as determined by appendix H ” to 40 CFR part 50. We consider that a monitor exceeds the 1 - hour ozone standard when that ambient air quality monitor records a 1 - hour average ozone concentration above 0.12 ppm at least once in any given calendar day. Only the maximum 1 - hour ozone conc entration at the monitor during any calendar day is considered when determining if the 1 - hour ozone NAAQS was exceeded on 4 As noted elsewhere in this proposed determination, the monitoring data show that the Baltimore area has been attaining the 1 - hour ozone standard continuously since 2008 .9

that day. That is, even when a monitor records more than one hourly concentration above 0.12 ppm during a calendar day, that day coun ts as only a single “ exceeda nce day. ” See , 40 CFR 50.9 “National 1 - hour primary and secondary ambient air quality standards for ozone” and “Interpretation of the 1 - Hour Primary and Secondary National Ambient Air Quality Standards for Ozone” (40 CFR part 50, appendix H). B. What are the Relevant Data Handling and Rounding Conventions for the 1 - hour Ozone NAAQS? Although the 1 - hour ozone NAAQS as promulgated in 40 CFR 50.9 does not address of specific data handling conventions, EPA’s publicly articula ted position and the approach that the air quality management community has long universally adopted, is that the interpretation of the 1 - hour ozone standard requires rounding ambient air quality data consistent with the stated level of the standard, which is 0.12 ppm. As early as 1979, EPA’s guidance noted that the level as it is expressed in the standard defines the number of significant figures to be used in determining whether the standard was exceeded. The stated level of the standard is taken as defining the number of significant figures to be used in comparisons with the standard. For example, a standard level of 0.12 ppm means that measurements are to be rounded to two decimal places (0.005 rounds up), and, therefore, 0.125 ppm is the smallest concentration value in excess of the level of the standard . See , “Guideline for the Interpretation of Ozone Air Quality Standards,” EPA - 450/4 - 79 - 003, OAQPS No. 1.2 - 108, January 1979. EPA has consistently applied the rounding convention in this 1979 guide line. example, See , 68 FR 19106 at 19111, April 17, 2003; 68 FR 62041 at 62043, October 31, 2003; and 69 FR 21717 at 21719, April 22, 2004. In the 1990 CAA Amendments, Congress expressly recognized the continuing validity of EPA guidance in the 1990 CAA Amendments. See , generally, H Comm. Rep. 101 - 490 pp. 197, 232 (1990) (House Energy and Commerce Committee Report). A nonattainment area attains the 1 - hour ozone NAAQS only when all monitors in that area attain the 1 - hour ozone NAAQS . C. How is t he Nu mber of Expected Exceedance Days Determined, and, How i s Attainment Determined u nder the Form of the 1 - Hour Ozone NAAQS ? EPA determines if an area has attained the 1 - hour ozone NAAQS by calculating, at each monitor, the average expected number of days ov er the standard per year (i.e., “ average number of expected exceedance days”) during the applicable 3 - year period. See , generally the General Preamble, 57 FR 13498 at 13506, April 16, 1992 and Memorandum from D. Kent Berry, Acting Director, Air Quality Ma nagement Division, EPA to Regional Air Office Directors; “Procedures for Processing Bump Ups and Extensions for Marginal Ozone Nonattainment Areas,” February 3, 1994. A monitor shows attainment when the average number of “expected” number of10

“ exceedan ce days ” per calendar year “ is less than or equal to one (1) ” when averaged over a three - year period . . The level of the standard defines the number of significant figures to be used in comparisons with the standard which in this case means all averages are rounded to one significant figure. The smallest value which will exceed this standard is a value of 1.1, and, the average over a 3 - year period is therefore rounded to one significant figure. Therefore, a violation occurs when the average number of ex pected exceedance days over a consecutive 3 - year period is greater than or equal to 1.1. Therefore, to not violate the 1 - hour ozone NAAQS, the maximum aggregate sum of expected exceedance days over a consecutive 3 - year period allowed is 3.1 because 3.1 di vided by 3 is 1.03333, which when rounded to one significant figure is 1.0 which does not exceed 1. An aggregate sum of 3.2 expected exceedance days over a consecutive 3 - year period do not meet this standard because 3.2 divided by 3 equals 1.0666, which w hen rounded to one significant figure is 1.1 and therefore is greater than 1.0. See, 40 CFR part 50 appendix H and see , Memorandum from D. Kent Berry, Acting Director, Air Quality Management Division, EPA, to Regional Air Office Directors; “Procedures for Processing Bump Ups and Extensions for Marginal Ozone Nonattainment Areas,” dated February 3, 1994. 1. Estimating expected exceedance days from actual number of observed exceedances to account for missing data: An observed daily maximum value at a monitor is considered to be valid if 75 percent of the hours from 9:01 a.m. to 9:00 p.m. were measured or if the highest hourly value measured is greater than the level of the standard . Where there are either no data for a day or data for less than the 75 percent of the hours between 9 a . m . and 9 p . m . , a missing daily maximum ozone value may be assumed to be less than the level of the standard if the valid daily maxima on both the preceding day and the following day do not exceed 75 percent of the level of the standard . A day for which the daily maximum ozone value may be assumed to be less than 0.0125 ppm is termed “day assumed less than the standard.” See , appendix H to 40 CFR part 50. To account for missing data, the procedures in appendix H to 40 CFR part 50 are used to adjust the actual number of monitored exceedances of the standard in a year to yield the annual number of “expected exceedance days ” (or “expected exceedance days”) at an air quality monitoring site. The following equation is used to convert the actual number of measured exceedances into an estimate of the annual number of “expected exceedance days :”

e = v + [ (v∕n) • (N

- n - z)] (The “•” symbol indicates multiplication, and, the “∕”symbol indicates division.) where: e = the e stimated number of expected exceedance days for the year (denoted by “EST DAYS >/= .125” in the AQS reports), N = the number of required monitoring days in the year,11

n = the number of valid daily maxima, v = the number of daily values above the level of the standard, denoted by “DAYS MAX >/= 0.125” in the AQS reports and z = the number of days assumed to be less than the standard level, denoted by “MISSED DAYS < 0.125” in the AQS reports. This estimated number of exceedance days , e , shall be round ed to one decimal place (fractional parts equal to 0.05 and higher round up). See , Appendix H to 40 CFR part 50 . The minimum required monitoring season for all parts of Maryland is 214 days from April 1 st to October 31 st of every year. See , 40 CFR 58 .11(c) and Table D - 3 “Ozone Monitoring Seasons by State” in appendix D to 40 CFR part 58 . Therefore, the number of required monitoring days in the year, N, always equals 214. 2. Rounding of the number of expected exceedance days : The computation of “expected exceedance days ” is rounded to one significant figure for both the purposes of estimating the annual number of expected exceedance days at a monitor and for the annual average number of expected exceedance days over a 3 - year period. For example , for the 3 - year average, any value less than 1.05 rounds down to 1.0, and, any value of 1.05 or greater rounds up to 1.1. B ecause a violation occurs when the average number of expected exceedance days over a consecutive 3 - year period is greater than 1 , a violation occurs only when the average number of expected exceedance days over a consecutive 3 - year period is greater than 1.0. Therefore, to not violate the 1 - hour ozone NAAQS , the maximum aggregate sum of expected exceedance days over a consecutive 3 - y ear period allowed is 3.1 because 3.1 divided by 3 is 1.03333, which when rounded to one significant figure is 1.0 which does not exceed 1. An aggregate sum of 3.2 expected exceedance days over a consecutive 3 - year period do not meet this standard because 3.2 divided by 3 equals 1.0666, which when rounded to one significant figure is 1.1 which is greater than 1.0. Example Calculation: Suppose a monitor in Maryland had the following data for the 2006 ozone season: the number of required monitoring days in the year, N, = 214 the number of valid daily maxima, n, = 211 the number of daily values above the level of the standard, v, = 2 the number of days assumed to be less than the standard level, z, = 1 Therefore,12

e = v + [ (v∕n) • (N

- n - z)] = 2 + [(2/211) (214 - 211 - 1)] = 2.018, which rounds to 2.0 estimated number of expected exceedance days for calendar year 2006. Refer to Appendix A to this document for more details on the air quality data and examples of ho w the annual number of “expected exceedance days ” was calculated from monitored data to account for missing days. Appendix A also contains the relevant air quality data reports downloaded from AQS. 3. Source of air quality data: A determination of w hether an area's air quality meets the 1 - hour ozone standard is based upon three years of complete, quality - assured and certified air quality monitoring data gathered at established State and Local Air Monitoring Stations (``SLAMS'') in the nonattainment a rea and entered into the EPA's Air Quality System (AQS) database. Data from air monitors operated by state/local agencies in compliance with EPA monitoring requirements must be submitted to the AQS database. Monitoring agencies must annually certify that these data are accurate to the best of their knowledge , and, for calendar years 2010 and later, such certifications must be submitted by May 1 st for the prior year’s data . See , 40 CFR 58.15. Thus, the certification of the air quality monitoring data for calendar year 2011 is due no later than May 1, 2012 . Accordingly, EPA relies primarily on data in its AQS database when determining the attainment status of an area. See, 40 CFR 50.9; 40 CFR part 50, appendix H; 40 CFR part 53; 40 CFR part 58, appendice s A, C, D and E. All data are reviewed to determine the area's air quality status in accordance with 40 CFR part 50, appendix H. V. What is EPA’s Analysis of the Data Regarding Baltimore’s Attainment of the 1 - Hour Ozone Standard? A. What were the M on itors in the Baltimore Area during 2003 through 2010? Table 3 summarizes the descriptive information for the ozone monitors in operation at any time during the 2003 to 201 1 period. The “short name” will be used in subsequent tables to identify a monito r by name. Table 3 . Monitor Information Baltimore Area 2006 - 2010 Monitor (AQS ID No.) Location Short name Years of operation (inclusive) 2003 - 2011 24 - 510 - 0054 Furley E.S. Recreational Center,

4633 Furley Avenue, Baltimore City Furley 2006 - 2011 24 - 0 03 - 0014 Davidsonville Recreation Center,

3801 Queen Anne Bridge Road, Davidsonville 2003 - 201113 Anne Arundel County 24 - 005 - 1007 Padonia Elementary School, 9834

Greenside Drive, Cockeysville, Baltimore County Padonia 2003 - 2011 24 - 005 - 3001 600 Dorsey Ave nue, Essex,

Baltimore County Essex 2003 - 2011 24 - 013 - 0001 1300 W. Old Liberty Road, Carroll

County South Carroll 2003 - 2011 24 - 025 - 1001 Edgewood Chemical Biological

Center (APG), Waehli Road, Edgewood, Harford County Edgewood 2003 - 2011 24 - 025 - 9001 356 0 Aldino Road, Harford County Aldino 2003 - 2011 24 - 003 - 0019 ‘Y’ Street, Fort Meade, Anne

Arundel Co., MD Fort Meade 2003 - 2004 24 - 510 - 0053 299 Ponca Street, Baltimore City,

MD Ponca Street 2003 Source: EPA AQS Database, “Quicklook Criteria Parameters,” Re port Request ID 843146, Report Code AMP450, dated March 3, 2011, for the 2009 to 2010 data and Report Request ID 937336, Report Code AMP450, dated December 13, 2011, for the 2011 data. B . What is EPA’s Analysis of w hether the Baltimore Area a ttained the 1 - hour Ozone Standard by its 2005 Attainment Deadline? As noted previously, the applicable attainment date under the 1 - hour ozone NAAQS for the Baltimore area was November 15, 2005. We base a determination regarding attainment of the 1 - hour ozone NAAQS by this deadline on the average number of expected exceedance days per year for the period 2003 - 2005. During the entire 2003 to 2005 period, six ozone monitoring stations in the Baltimore area were in operation. Table 4 summarizes the ozone data collec ted at these six ozone monitoring stations during the 2003 to 2005 period and included in AQS for the Baltimore area. These data are complete and have been quality - assured and recorded in AQS. Maryland uses the AQS as the permanent database to maintain i ts data and quality assure the data transfers and content for accuracy. We have used the established rounding conventions set forth in our guidance documents and regulations. Table 4 . Number and Average Number of Ozone Expected Exceedance Days and D esign values per Year by Monitor in the Baltimore area 2003 to 2005 Monitor Information Annual Number of Expected Exceedance Day s Average Number of Expected Exceedance Days Per Year Monitor (AQS ID No.) 2003 2004 2005 2003 - 0514

Davidsonville Recrea tion Center, 3801 Queen Anne Bridge Road, Anne Arundel County ( 24 - 003 - 0014) 2.1 0.0 0.0 0.7 Padonia Elementary School, 9834 Greenside Drive, Cockeysville, Baltimore County ( 24 - 005 - 1007) 0.0 0.0 0.0 0.0 600 Dorsey Avenue, Essex, Baltimore County ( 24 - 005 - 3001) 1.0 0.0 1.0 0.7 1300 W. Old Liberty Road, Carroll County ( 24 - 013 - 0001) 0.0 0.0 0.0 0.0 Edgewood Chemical Biological Center (APG), Waehli Road, Edgewood, Harford County (24 - 025 - 1001) 1.0 1.0 2.0 1.3 3560 Aldino Road, Harford County (24 - 025 - 9001) 1 .0 0.0 1.0 0.7 Source: EPA AQS Database, “Quicklook Criteria Parameters,” Report Request ID 843146, Report Code AMP450, dated March 3, 2011. For the “Average number of expected exceedance days per year” column , two sample calculations follow: For the “Essex” monitor: “Average number of expected exceedance days per year” = (1.0 + 0.0 + 1.0)/3 = 0.67 = 0.7 rounded. For the “Edgewood” Monitor: “Average number of expected exceedance days per year” = (1.0 + 1.0 + 2.0)/3 = 1.333 = 1.3 rounded. As shown in Table 4 and the preceding sample calculation, the average number of expected exceedance days per year was greater than 1.0 at the “Edgewood” monitor (AQS ID# 24 - 025 - 1001). In addition to the six monitors listed in Table 4 , two other monitors d iscontinued during the 2003 - 2005 period. These were the Fort Meade (ID# 24 - 003 - 0019) and the Ponca Street (ID# 24 - 510 - 0053) monitors. Because the “Edgewood” Monitor (AQS ID # 24 - 025 - 1001) violated the ozone NAAQS in 2005 the data for these two monitors i s not necessary to determine if the Baltimore area attained the 1 - hour ozone NAAQS by November 15, 2005.15

Therefore, based upon analysis of the air quality data, EPA can conclude the Baltimore area failed to attain the 1 - hour ozone NAAQS by November 15, 2005, which was the applicable attainment date under the 1 - hour ozone NAAQS for this nonattainment area. C. Could an Extension of the Severe - 15 Area Attainment Date b een g ranted for the Baltimore Area? Pursuant to section 181(a)(5) of the CAA, the sta te may request, and EPA may grant, up to two one - year attainment date extensions. EPA may grant an extension if both of two criteria are met. One of these criteria is: the area shall not measure more than one exceedance of the ozone standard at any monit oring site in the nonattainment area in the year in which attainment is required. As shown in Table 4 (see section V.B of this document), the Edgewood, Harford County monitoring site recorded two (2) exceedances in 2005 which was the year in which attai nment is required. Therefore, one criterion in section 181(a)(5) was not met, and, therefore, Baltimore area was not eligible for an attainment date extension under section 181(a)(5). D . What is EPA's Analysis of w hether the Baltimore Area is currentl y attaining the 1 - Hour Ozone Standard? During the entire period from 2006 through 2011, the same seven ozone monitoring stations in the Baltimore area were in operation. These are listed in T able 3 above. Table 5 summarizes the 1 - hour ozone data col lected at these six ozone monitoring stations during the 2006 to 2010 period and included in AQS for the Baltimore area. These data are complete and have been quality - assured , certified by the state and recorded in AQS. Maryland uses the AQS as the perm anent database to maintain its data and to quality - assure the data transfers and content for accuracy. We have used the established rounding conventions set forth in our guidance documents and regulations. Table 5 . Number and Average Number of Ozone Expected Exceedance Days per Year by Monitor in the Baltimore area 2006 to 2010 Monitor Information Annual Number of Expected Exceedance Days Average Number of Expected Exceedance Days Per Year Monitor – AQS ID No. & “Short Name” 2006 2007 2008 2009 20 10 2006 - 2008 2007 -

2009 2008 -

2010 24 - 510 - 0054

– Furley 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 24 - 003 - 0014

– Davidsonville 0.0 1.0 0.0 0.0 0.0 0.3 0.3 0.0 24 - 005 - 1007

– 0.0 0.0 1.0 0.0 0.0 0.3 0.3 0.016

Padonia 24 - 005 - 3001

– Essex 1.0 0.0 0.0 0.0 1.0 0.3 0.0 0 .3 24 - 013 - 0001

– South Carroll 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 24 - 025 - 1001

– Edgewood 2.0 1.0 0.0 1.0 1.1 1.0 0.7 0.7 24 - 025 - 9001

– Aldino 1.0 2.0 0.0 0.0 0.0 1.0 0.7 0.0 Source: EPA AQS Database, “Quicklook Criteria Parameters,” Report Request ID 8 43146, Report Code AMP450, dated March 3, 2011. Table 6 summarizes the 1 - hour ozone data collected at these seven ozone monitoring stations during the 2009 to 2011 period and included in AQS for the Baltimore area. These data for 2009 and 2010 are compl ete and have been quality - assured , certified and recorded in AQS. The data for 2011 are those entered in AQS as of December 13, 2011 . Data for at least 90 percent of the 2011 monitoring season days has been entered into AQS but has not yet been certifie d by Maryland . 5 The data shows that only one monitor recorded an exceedance of the 1 - hour ozone standard; the Edgewood site measured one exceedance of the 1 - hour ozone standard during 2011 . As of December 13, 20111, the 2011 data entered into AQS for the Edgewood site includes 209 days of valid data and also includes three days assumed less than the standard. Under the procedures discussed in Section IV “How Does EPA Compute Whether an Area Complies with the 1 - Hour Ozone NAAQS?” elsewhere in this documen t, the number of expected exceedance days for the Edgewood site is only 1.0 for 2011. Table 6 . Number and Average Number of Ozone Expected Exceedance Days per Year by Monitor in the Baltimore area 2009 to 2011 Monitor Information Annual Number of Exp ected Exceedance Days Average Number of Expected Exceedance Days Per Year Monitor – AQS ID No. & “Short Name” 2009 2010 2011 2009 - 2011 24 - 510 - 0054

– Furley 0.0 0.0 0.0 0.0 24 - 003 - 0014

– Davidsonville 0.0 0.0 0.0 0.0 24 - 005 - 1007

– Padonia 0.0 0.0 0 .0 0.0 24 - 005 - 3001

– Essex 0.0 1.0 0.0 0.3 24 - 013 - 0001

– South Carroll 0.0 0.0 1.0 0.0 24 - 025 - 1001

– Edgewood 1.0 1.1 1.0 1.0 24 - 025 - 9001

– Aldino 0.0 0.0 0.0 0.0 Source: EPA AQS Database, “Quicklook Criteria Parameters,” Report Request ID 843146, Report Code AMP450, dated March 3, 2011, for the 2009 to 2010 data and Report Request ID 937336, Report Code AMP450, dated December 13, 2011, for the 2011 data. As shown in Tables 5 and 6 , no monitor in the Baltimore area had a value of the average numbe r of expected exceedance days per year exceeding 1.0 in the three - year period 2006 - 2008. 5 As noted in section IV.C.3 of this document, the deadline for certifying the 2011 data is May 1, 2012.17

Furthermore, no monitor in the Baltimore area has had a value of the average number of expected exceedance days per year exceeding 1.0 in any three - year period after 2006 - 2008, that is, during the subsequent three - year periods 2007 - 2009 and 2008 - 2010. Thus the data show that the Baltimore area attained the 1 - hour ozone standard in 2008 and has continued to attain this standard through 2010 based upon the most recent complete, quality - assured and certified data. Preliminary data available for 2011 indicate that the area continues in attainment for the 1 - hour ozone standard for the period 2009 through 2011. Therefore, EPA can propose to find that the Baltimore area attained the 1 - hour ozone NAAQS by November 15, 2008 and has remained in attainment through the end of 2010 the last year for which quality assured data has been recorded in AQS and continues in attainment based upon the preliminary data available for 2011 . VI. CONCLUSIONS AND RECOMMENDED AGENCY ACTION . Therefore, I recommend that EPA propose the actions described in the two following paragraphs: A. Attainment by November 15, 2005: Pursuant to EPA’s authority to ensure implementation of 1 - hour oz one anti - backsliding requirements (CAA sections 301 and section 181(b)(2) ) and based upon EPA's review of complete, quality - assured and certified ozone monitoring data for the three - year period 2003 to 2005, EPA can propos e to determine that the Baltimore severe 1 - hour ozone nonattainment area failed to attain the 1 - hour ozone NAAQS by the applicable attainment date of November 15, 2005 . B. Clean Data Policy determination of attainment and contingency measures: EPA can propos e to determine that the Balti more area is currently attaining the 1 - hour ozone NAAQS, based upon the most recent three years of complete, quality - assured and certified ambient air monitoring data (2008 - 2010). The preliminary data that is available for 2011 show that the area continue s to attain the standard. Moreover, the Baltimore area has monitored attainment of the 1 - hour ozone NAAQS since the 2006 - 2008 monitoring period. If this proposed determination is made final, the obligation for the State of Maryland to submit contingency measures related to attainment of the 1 - hour ozone NAAQS in the Baltimore severe 1 - hour ozone nonattainment area would be suspended. These proposed determinations regarding the 1 - hour ozone standard, if finalized, would bear on the Baltimore area’s obliga tions with respect to the 1 - hour ozone anti - backsliding requirements for section 172(c)(9) contingency measures for failure to attain that standard, and sections 182(d)(3) and 185 major stationary source fee programs. .18

List of EPA Guidance Memos and D ocuments A. Guidance Memos and Documents

• “Guideline for the Interpretation of Ozone Air Quality Standards,” EPA - 450/4 - 79 - 003, OAQPS No. 1.2 - 108, January 1979. • “General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990,” 57 FR 13498, April 16, 1992. • Memorandum from D. Kent Berry, Acting Director, Air Quality Management Division, EPA, to Regional Air Office Directors; “Procedures for Processing Bump Ups and Extensions for Marginal Ozone Nonattainment Areas,” dated February 3, 1994. • Memorandum from William G. Laxton, Director, Technical Support Division (MD 14), entitled “Ozone and Carbon Monoxide Design Value Calculations,” dated June 18, 1990. List of Appendices

• Appendix A to Technical Support Document

– Det ermination of Failure to Attain by 2005 and Determination of Attainment by 2008 for the 1 - Hour Ozone National Ambient Air Quality Standards in the Baltimore Nonattainment Area in Maryland [EPA - R03 - OAR - 2011 - 0680]

• A ppendix B To: Determination of Failure to Attain by 2005 and Determination of Attainment by 2008 for the 1 - Hour Ozone National Ambient Air Quality Standards in the Baltimore Nonattainment Area in Maryland [EPA - R03 - OAR - 2011 - 0680]1

Appendix A to Technical Support Document – Determination of Failure to Attain by 2005 and Determination of Attainment by 2008 for the 1 - Hour Ozone National Ambient Air Quality Standards in the Baltimore Nonattainment Area in Maryland [ EPA - R03 - OAR - 20 11 - 0680 ] In section 3 “ Estimating the Number of Exceedance s for a Year” of Appendix H to Part 50

— “ Interpretation of the 1 - Hour Primary and Secondary National Ambient Air Quality Standards for Ozone ,” a procedure is specified for determin ing when the expected num ber of days per calendar year with maximum hourly average concentrations above 0.12 ppm (235 μg/m 3 ) 1 is equal to or less than 1. For purposes of clarity in the following discussion, it is convenient to use the term “exceedance” to describe a daily maximu m hourly average ozone measurement that is greater than the level of the standard. As discussed in section IV.B of the main body of this document, a measured value of 0.124 ppm rounds down to 0.12 ppm and does not constitute a monitored exceedance of the 0 .12 ppm NAAQS. Values of 0.125 ppm and higher round up and do constitute a monitored exceedance of the 0.12 ppm NAAQS. The phrase “expected number of days with maximum hourly average ozone concentrations above the level of the standard” over a 3 - year p eriod may be simply sta ted as the “ average number of expected exceedance day s” over a 3 - year period . The basic principle in making this determination is relatively straightforward. Most of the complications that arise in determining the expected number of exceedance days per calendar year relate to accounting for incomplete sampling. In general, the average number of exceedance days per calendar year must be less than or equal to 1. In its simplest form, the number of exceedance days at a monitoring si te would be recorded for each calendar year and then averaged over the past 3 calendar years to determine if this average is less than or equal to 1. EPA’s Interpretation of Expected Exceedance Days is as follows: The ozone standard states that the ave rage number of expected number of exceedance days per year must be less than or equal to 1. The statistical term “expected number” is basically an arithmetic average. The following example explains what it would mean for an area to be in compliance with th is type of standard. Suppose a monitoring station records a valid daily maximum hourly average ozone value for every day of the year during the past 3 years . At the end of each year, the number of days with maximum hourly concentrations above 0.12 ppm is d etermined and this number is averaged with the results of previous years. As long as this average remains “less than or equal to 1,” the area is in compliance. In general, a valid daily maximum hourly average value may not be available for each day of the year, and it will be necessary to account for these missing values when estimating the number of exceedance days for a particular calendar year. The purpose of these computations is to determine if the expected number of exceedance days per year is less t han or equal to 1. Thus, if a site has two or 1 In the main body of this document the phrase “ expected number of days per calendar year with maximum hourly average concentrations above 0.12 ppm (235 μg/m 3 ) ” is termed “expected exceedance days per calendar year.”2

more observed exceedance days each year (or more than four over a three year period) , the standard is not met and it is not necessary to use the procedures of Appendix H to account for incomplete sampling. The term “missing value” is used here in the general sense to describe all days that do not have an associated ozone measurement. In some cases, a measurement might actually have been missed but in other cases no measurement may have been scheduled for that d ay. A daily maximum ozone value is defined to be the highest hourly ozone value recorded for the day. This daily maximum value is considered to be valid if 75 percent of the hou rs from 9:01 a.m. to 9:00 p.m. were measured or if the highest hour is greater than the level of the standard. In some areas, the seasonal pattern of ozone is so pronounced that entire months need not be sampled because it is extremely unlikely that the standard would be exceeded. Any such waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58. In the c ase o f Maryland no moni toring is required under Table D - 3 “ Ozone Monitoring Season by State ” to Appendix D of 40 CFR Part 58 for the period of November 1 st through March 31 st (inclusive). The refore, the number of required monitoring days in the year for these states is 214 (April 1 st through October 31 st inclusive). Some allowance should also be made for days for which valid daily maximum hourly values were not obtained but which would qui te likely have been below the standard. Such an allowance introduces a complication in that it becomes necessary to define under what conditions a missing value may be assumed to have been less than the level of the standard. The following criterion may be us ed for ozone: A missing daily maximum ozone value may be assumed to be less than the level of the standard if the valid daily maxima on both the preceding day and the following day do not exceed 75 percent of the level of the standard. Let z denote the nu mber of missing daily maximum values that may be assumed to be less than the standard. Then Appendix H requires that the following formula shall be used to estimate the expected number of exceedance days for the year: e = v + [ (v

∕ n) • (N - n - z)] ( The “•” sy mbol i ndicates multiplication , and, the “ ∕ ”symbol indicates division .) where: e = the estimated number of exceedance days for the year (denoted by “EST DAYS >/= .125” in the AQS reports) ,3

N = the number of required monitoring days in the year, n = the numb er of valid daily maxima, v = the number of daily values above the level of the standard, denoted by “DAYS MAX >/= 0.125” in the AQS reports and z = the number of days assumed to be less than the standard level , denoted by “MISSED DAYS < 0.125” in the AQS reports . This estimated number of exceedance days shall be rounded to one decimal place (fractional parts equal to 0.05 and higher round up). Generally, after using the rounding convention, this formula yields a result that expected number of exceedance da ys at a monitor for a year is equal to the measured number when the number of valid daily maxima is close to the number of required monitoring days in the year . For a monitor required to monitor 214 days per year with one measured exceedance ( a daily ma xima greater than 0.124 ppm), the monitor needs at least 204 valid daily maxima (assuming “z,” the number of days assumed to be less than the standard level , is zero ) to have the expected number of exceedance days remain less than 1.1. Using the formula f or such a case, e = 1 + [ ( 1∕204 ) • ( 214 - 204 - 0 )] = 1+10/204 = 1.049 which rounds down to 1.0. If the monitor measured two exceedances then the monitor needs at least 209 valid daily maxima (assuming z = zero the number of days assumed to be less than the s tandard level ) to have the expected number of exceedance days remain less than 2.1. Using the formula for such a case, e = 2 + [ ( 1∕209 ) • ( 214 - 209 - 0 )] = 2 +5/204 = 2.047 which rounds down to 2 .0. If the number of valid daily maxima was 208 then the form ula would yield: e = 2 + [ ( 1∕208 ) • ( 214 - 208 - 0 )] = 2 +6/204 = 2.057 which rounds up to 2 . 1 . EPA’s AQS automatically performs these calculations when preparing certain reports such as the US EPA Air Quality System (AQS) Quick Look report (AMP450). Exampl e calculations for selected monitors with the fewest number of valid daily maxima and with one or more recorded exceedances are provided below. A summary of the 1 - hour ozone monitoring data for the se monitors is presented in Table A - 1. The data for these monitors are in two reports titled “US EPA Air Quality System (AQS) Quick Look Criteria Parameters (AMP450)” dated March 3, 2011 and December 13, 2011 . Table A - 1 1 - Hour Ozone Monitoring Data for Selected Monitors in the Baltimore Area and Years Monitor L ocation (Nonattainment Area) AQS ID Year N n v z e Davidsonville 24 - 003 - 0014 2003 214 20 5 2 1 2 .14

Essex 2 24 - 005 - 3001 2005 214 2 12 1 2 1.0 Essex 24 - 005 - 3001 2010 214 203 1 3 1.0 Edgewood 24 - 025 - 1001 2003 214 212 1 1 1.0 Edgewood 24 - 025 - 1001 2005 214 21 1 2 3 2.0 Edgewood 24 - 025 - 1001 200 6 214 21 1 2 1 2.0 Edgewood 24 - 025 - 1001 200 9 214 208 1 3 1.0 Edgewood 24 - 025 - 1001 20 10 214 199 1 1 1.1 Edgewood 24 - 025 - 1001 2011 214 209 1 3 1.0 Aldino 24 - 025 - 9001 2007 214 209 2 3 2.0 Source s : EPA AQS Database, “Quic klook Criteria Parameters,” Report Request ID 843146, Report Code AMP450, dated March 3, 2011 (Copy Attached) for the 2003 through 2010 (inclusive) years. EPA AQS Database, “Quicklook Criteria Parameters,” Report Request ID 937336, Report Code AMP450, date d December 13, 2011 (Copy Attached) for the 2011 data. Sample calculations follow: For Davidsonville in 2003, 

### e 200 3 = v + [ (v∕ n) • (N - n - z)] = 1 + [(1

∕ 20 5 ) • (214

– 20 5

– 1)] = 1 + [ 8 /20 5 ] = 1.0 39 9 which rounds to 1. 0. For Essex i n 200 5 , 

### e 200 5 = v + [ (v∕n) • (N - n - z)] = 1 + [( 1

∕ 2 12 • (214

– 2 12

– 2 )] = 1 + [ 0 /21 2 ] = 1.00 0 which rounds to 1 .0. For the Essex si te in 2010 , 

### e 20 10 = v + [ (v∕n) • (N - n - z)] = 1 + [(1

∕ 20 3 • (214

– 20 3

– 3 )] = 1 + [ 8 /20 3 ] = 1. 039 4 which rounds to 1.0. For the Edgewood site in 2003, 

### e 2003 = v + [ (v∕n) • (N - n - z)] = 1 + [(1

∕ 2 12 • (214

– 2 12

– 1 )] = 1 + [ 1/212 ] = 1.0 047 which rounds to 1.0.

2 Also would apply to the Carroll County monitor (AQS ID# 24 - 013 - 0001) for the year 2005, and, the Edgewood monitor (AQS ID# 24 - 025 - 1001) for the year 2007.5

For the Edgewood site in 200 5 , 

### e 200 5 = v + [ (v∕n) • (N - n - z)] = 2 + [( 2

∕ 2 11 • (214

– 21 1

– 3 )] = 2 + [ 0 /21 1 ] = 2 .0 00 which rounds to 2 .0. For the Edgewood site in 2006, 

### e 2006 = v + [ (v∕n) • (N - n - z)] = 2 + [( 2

∕ 211 • (214

– 211

– 1)] = 2 + [ 4 /211] = 2.01 9 which rounds to 2.0. For the Edgewood site in 200 9 , 

### e 200 9 = v + [ (v∕n) • (N - n - z)] = 1 + [(1

∕ 2 08 • (214

– 2 08

– 3)] = 1 + [3/208 ] = 1.0 14 which rounds to 1.0. For the Edgewood site in 20 10 , 

### e 20 10 = v + [ (v∕n) • (N - n - z)] = 1 + [(1

∕ 199 • (214

– 199

– 1 )] = 1 + [ 14/199 ] = 1.0 70 which rounds to 1. 1 . For the Edgewood site in 2011, 

### e 2011 = v + [ (v∕n) • (N - n - z)] = 1 + [(1

∕ 209 • (214

– 209

– 3)] = 1 + [ 2 /209] = 1.00 96 which rounds to 1.0. For the Aldino site in 200 7 , 

### e 200 7 5 = v + [ (v∕n) • (N - n - z)] = 2 + [( 2

∕ 2 09 • (214

– 2 09

– 3 )] = 1 + [ 4 /20 9 ] = 2 .0 19 which rounds to 2.0 . For any year where the observed number of daily values above the level of the standard is zero “ e ” is:

e = = v + [ (v∕

n) • (N - n - z)] = 0 + [0/n] = 0.0000

## Attachment to Appendix A to Technical Support Document – Determination of Failure to Attain by 2005 and Determination of Attainment by 2008 for the 1 - Hour Ozone National Ambient Air Quality Standards in the Baltimore Nonattainment Area in Maryland [EPA - R 03 - OAR - 2011 - 0680]: EPA AQS Database, “Quicklook Criteria Parameters,” Report Request ID 843146, Report Code AMP450, dated March 3, 2011. EPA AQS Database, “Quicklook Criteria Parameters,” Report Request ID 937336, Report Code AMP450, dated December 13, 2011, for the 2011 data.

## (This Page Left Blank on Purpose)UNITED STATES ENVIRONMENTAL PROTECTION AGENCY QUICKLOOK CRITERIA PARAMETERS Mar. 3, 2011 Report Request ID: 843146 Report Code: AMP450

Selection Criteria Page 1 User ID: AER

State County City

Site Parameter POC AQCR UAR CBSA CSA EPA Region Method Duration Begin Date End Date 24 24 24 24 24 003

005 510 013 025 GEOGRAPHIC SELECTIONS

PROTOCOL SELECTIONS Parameter Classification Parameter Method Duration QUICK LOOK 44201 1

SELECTED OPTIONS MERGE PDF FILES WORKFILE DELIMITER EVENTS PROCESSING Option Type Option Value YES , EXCLUDE REGIONALLY CONCURRED EVENTS SORT ORDER 1 2 3 4 5 6 7 Order Column

PARAMETER_CODE STATE_CODE COUNTY_CODE SITE_ID POC DATES EDT_ID GLOBAL DATES 2003 Start Date End Date 2010 Tribal

APPLICABLE STANDARDS Standard Description Ozone 1-hour Daily 2005Mar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 1 of 9 EXCEPTIONAL DATA TYPES EDT DESCRIPTION 0 1 2 5 NO EVENTS EVENTS EXCLUDED EVENTS INCLUDED EVENTS WITH CONCURRENCE EXCLUDEDMar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 2 of 9 Ozone (44201) Maryland Parts per million (007)

SITE ID P

O C PQAO CITY COUNTY ADDRESS YEAR METH VALID DAYS MEAS 1ST

MAX 1-HR CERT EDT 24-003-0014

24-003-0014

24-003-0014

24-003-0014

24-003-0014

24-003-0014

24-003-0014 1

1

1

1

1

1

1 1002

1002

1002

1002

1002

1002

1002 Not in a city
Not in a city
Not in a city
Not in a city
Not in a city
Not in a city
Not in a city Anne Arundel

Anne Arundel

Anne Arundel

Anne Arundel

Anne Arundel

Anne Arundel

Anne Arundel Davidsonville Recreation Center, 3801 Queen Anne Bridge Road Davidsonville Recreation Center, 3801 Queen Anne Bridge Road Davidsonville Recreation Center, 3801 Queen Anne Bridge Road Davidsonville Recreation Center, 3801 Queen Anne Bridge Road Davidsonville Recreation Center, 3801 Queen Anne Bridge Road Davidsonville Recreation Center, 3801 Queen Anne Bridge Road Davidsonville Recreation Center, 3801 2003

2004

2005

2006

2007

2008

2009 019

047

047

047

047

047

047 205

203

208

212

212

208

207 .142

.109

.114

.124

.142

.098

.090 .132

.101

.112

.111

.111

.095

.089 Y

Y

Y 0

0

0

0

0

0

0 2ND MAX 1-HR 1-HOUR NUM DAYS REQ 214

214

214

214

214

214

214 .103

.099

.112

.107

.110

.093

.083 3RD MAX 1-HR .102

.096

.110

.105

.104

.092

.080 4TH MAX 1-HR DAY MAX>/= 0.125 2

0

0

0

1

0

0 EST DAYS>/= .125 2.1

0.0

0.0

0.0

1.0

0.0

0.0 MISS DAYS< 0.125 1

1

1

2

2

4

3Mar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 3 of 9 Ozone (44201) Maryland Parts per million (007)

SITE ID P

O C PQAO CITY COUNTY ADDRESS YEAR METH VALID DAYS MEAS 1ST

MAX 1-HR CERT EDT
24-003-0014

24-003-0019
24-003-0019
24-005-1007
24-005-1007
24-005-1007
24-005-1007
24-005-1007 1

1

1

1

1

1

1

1 1002

1002
1002
1002
1002
1002
1002
1002 Not in a city

Fort Meade (U.S. Army) Fort Meade (U.S. Army) Cockeysville Cockeysville Cockeysville Cockeysville Cockeysville Anne Arundel

Anne Arundel
Anne Arundel
Baltimore
Baltimore
Baltimore
Baltimore
Baltimore Queen Anne Bridge Road Davidsonville Recreation Center, 3801 Queen Anne Bridge Road 9001 'Y'STREET,FT.ME ADE,ANNE ARUNDEL MD 9001 'Y'STREET,FT.ME ADE,ANNE ARUNDEL MD Padonia Elementary School, 9834 Greenside Drive Padonia Elementary School, 9834 Greenside Drive Padonia Elementary School, 9834 Greenside Drive Padonia Elementary School, 9834 Greenside Drive Padonia Elementary 2010

2003
2004
2003
2004
2005
2006
2007 047

019
019
047
047
047
047
047 207

208
212
214
214
208
213
214 .116

.128
.121
.110
.099
.114
.112
.093 .111

.118
.098
.103
.095
.106
.104
.088 Y

Y

Y

Y

Y 0

0
0
0
0
0
0
0 2ND MAX 1-HR 1-HOUR NUM DAYS REQ
214

214
214
214
214
214
214
214 .109

.106
.098
.094
.093
.100
.100
.087 3RD MAX 1-HR
.106

.104
.095
.091
.093
.093
.099
.087 4TH MAX 1-HR DAY MAX>/= 0.125
0

1
0
0
0
0
0
0 EST DAYS>/= .125
0.0

1.0
0.0
0.0
0.0
0.0
0.0
0.0 MISS DAYS< 0.125
1

1
0
0
0
0

1
0Mar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 4 of 9 Ozone (44201) Maryland Parts per million (007)

SITE ID P

O C PQAO CITY COUNTY ADDRESS YEAR METH VALID DAYS MEAS 1ST

MAX 1-HR CERT EDT
24-005-1007
24-005-1007
24-005-1007
24-005-3001 24-005-3001 24-005-3001 24-005-3001 24-005-3001 24-005-3001 24-005-3001 24-005-3001 24-013-0001 24-013-0001 1

1

1

1 1 1 1 1 1 1 1 1 1 1002
1002
1002
1002 1002 1002 1002 1002 1002 1002 1002 1002 1002 Cockeysville Cockeysville Cockeysville

Essex Essex Essex Essex Essex Essex Essex Essex Not in a city Not in a city Baltimore
Baltimore
Baltimore
Baltimore Baltimore Baltimore Baltimore Baltimore Baltimore Baltimore Baltimore Carroll Carroll School, 9834 Greenside Drive Padonia Elementary School, 9834 Greenside Drive Padonia Elementary School, 9834 Greenside Drive Padonia Elementary School, 9834 Greenside Drive 600 Dorsey Avenue 600 Dorsey Avenue 600 Dorsey Avenue 600 Dorsey Avenue 600 Dorsey Avenue 600 Dorsey Avenue 600 Dorsey Avenue 600 Dorsey Avenue 1300 W. Old Liberty Road 1300 W. Old 2008

2009
2010
2003 2004 2005 2006 2007 2008 2009 2010 2003 2004 047
047
091
047 047 047 047 047 047 047 047 019 019 214
214
212
214 213 212 213 208 208 200 203 213 205 .129

.090
.110
.126 .117 .136 .137 .113 .117 .104 .128 .103 .115 .111

.085
.101
.109 .101 .109 .124 .103 .099 .099 .112 .099 .093 Y Y Y

Y Y 0
0
0
0 0 0 0 0 5 0 0 0 0 2ND MAX 1-HR 1-HOUR NUM DAYS REQ
214
214
214
214 214 214 214 214 214 214 214 214 214 .103
.084
.099
.095 .100 .104 .114 .101 .096 .090 .103 .095 .091 3RD MAX 1-HR
.103

.083
.096
.094 .097 .101 .111 .100 .095 .085 .100 .088 .088 4TH MAX 1-HR DAY MAX>/= 0.125
1
0
0

1 0 1 1 0 0 0 1 0 0 EST DAYS>/= .125
1.0
0.0
0.0
1.0 0.0 1.0 1.0 0.0 0.0 0.0 1.0 0.0 0.0 MISS DAYS< 0.125
0
0
2
0 1 2 1 4 5 3 3 1 3Mar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 5 of 9 Ozone (44201) Maryland Parts per million (007)

SITE ID P

O C PQAO CITY COUNTY ADDRESS YEAR METH VALID DAYS MEAS 1ST

MAX 1-HR CERT EDT 24-013-0001 24-013-0001 24-013-0001 24-013-0001 24-013-0001 24-013-0001 24-025-1001

24-025-1001

24-025-1001

24-025-1001 1

1 1 1 1 1 1

1

1

1 1002 1002 1002 1002 1002 1002 1002

1002

1002

1002 Not in a city Not in a city Not in a city Not in a city Not in a city Not in a city Edgewood
Edgewood
Edgewood
Edgewood Carroll Carroll Carroll Carroll Carroll Carroll Harford

Harford

Harford

Harford Liberty Road 1300 W. Old Liberty Road 1300 W. Old Liberty Road 1300 W. Old Liberty Road 1300 W. Old Liberty Road 1300 W. Old Liberty Road 1300 W. Old Liberty Road Edgewood Chemical Biological Center (APG), Waehli Road Edgewood Chemical Biological Center (APG), Waehli Road Edgewood Chemical Biological Center (APG), Waehli Road Edgewood Chemical Biological Center (APG), Waehli Road 2005

2006 2007 2008 2009 2010 2003

2004

2005

2006 047 047 047 047 047 047 047

047

047

047 212 211 213 211 212 211 212

212

211

211 .111

.122 .120 .108 .088 .112 .153

.126

.133

.129 .106

.103 .119 .103 .083 .094 .119

.111

.130

.126 Y

Y

Y

Y 0 0 0 0 0 0 0

0

0

0 2ND MAX 1-HR 1-HOUR NUM DAYS REQ 214 214 214 214 214 214 214

214

214

214 .104 .093 .115 .096 .076 .093 .115

.103

.122

.120 3RD MAX 1-HR .103

.092 .111 .089 .075 .091 .105

.103

.119

.109 4TH MAX 1-HR DAY MAX>/= 0.125 0 0 0 0 0 0 1

1

2

2 EST DAYS>/= .125 0.0 0.0 0.0 0.0 0.0 0.0 1.0

1.0

2.0

2.0 MISS DAYS< 0.125 2 0 1 3 2 1 1

0

3

1Mar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 6 of 9 Ozone (44201) Maryland Parts per million (007)

SITE ID P

O C PQAO CITY COUNTY ADDRESS YEAR METH VALID DAYS MEAS 1ST

MAX 1-HR CERT EDT 24-025-1001

24-025-1001

24-025-1001

24-025-1001

24-025-9001 24-025-9001 24-025-9001 24-025-9001 24-025-9001 24-025-9001 24-025-9001 1

1

1

1

1 1 1 1 1 1 1 1002

1002

1002

1002

1002 1002 1002 1002 1002 1002 1002 Edgewood
Edgewood
Edgewood
Edgewood
Not in a city Not in a city Not in a city Not in a city Not in a city Not in a city Not in a city Harford

Harford

Harford

Harford

Harford Harford Harford Harford Harford Harford Harford Edgewood Chemical Biological Center (APG), Waehli Road Edgewood Chemical Biological Center (APG), Waehli Road Edgewood Chemical Biological Center (APG), Waehli Road Edgewood Chemical Biological Center (APG), Waehli Road 3560 Aldino Road 3560 Aldino Road 3560 Aldino Road 3560 Aldino Road 3560 Aldino Road 3560 Aldino Road 3560 Aldino 2007

2008

2009

2010

2003 2004 2005 2006 2007 2008 2009 047

047

047

091

019 019 047 047 047 047 047 212

202

208

199

214 213 213 214 209 212 213 .133

.115

.133

.129

.125 .117 .134 .127 .139 .118 .112 .121

.115

.123

.119

.118 .108 .121 .114 .132 .110 .091 Y Y Y 0

5

0

0

0 0 0 0 0 5 0 2ND MAX 1-HR 1-HOUR NUM DAYS REQ 214

214

214

214

214 214 214 214 214 214 214 .111

.115

.119

.113

.101 .104 .112 .113 .119 .103 .090 3RD MAX 1-HR .108

.105

.098

.112

.098 .101 .108 .107 .117 .102 .086 4TH MAX 1-HR DAY MAX>/= 0.125 1

0

1

1

1 0 1 1 2 0 0 EST DAYS>/= .125 1.0

0.0

1.0

1.1

1.0 0.0 1.0 1.0 2.0 0.0 0.0 MISS DAYS< 0.125 2

1

3

1

0 1 0 0 3 0 1Mar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 7 of 9 Ozone (44201) Maryland Parts per million (007)

SITE ID P

O C PQAO CITY COUNTY ADDRESS YEAR METH VALID DAYS MEAS 1ST

MAX 1-HR CERT EDT 24-025-9001 24-510-0053 24-510-0054
24-510-0054
24-510-0054
24-510-0054
24-510-0054 1

1 1

1

1

1

1 1002 1002 1002
1002
1002
1002
1002 Not in a city Not in a city Baltimore
Baltimore
Baltimore
Baltimore
Baltimore Harford

Baltimore (City) Baltimore (City) Baltimore (City) Baltimore (City) Baltimore (City) Baltimore (City) Road 3560 Aldino Road 299 PONCA STREET Furley E.S. Recreational Center, 4633 Furley Avenue. Furley E.S. Recreational Center, 4633 Furley Avenue. Furley E.S. Recreational Center, 4633 Furley Avenue. Furley E.S. Recreational Center, 4633 Furley Avenue. Furley E.S. Recreational Center, 4633 Furley Avenue. 2010

2003 2006
2007
2008
2009
2010 047 019 047
047
047
047
091 210

61 71
206
214
198
187 .103

.074 .100
.094
.098
.089
.118 .103

.064 .090
.090
.071
.082
.101 Y 0 0 0
0
0
0
0 2ND MAX 1-HR 1-HOUR NUM DAYS REQ 214 214 214
214
214
214
214 .096 .060 .083
.089
.068
.080
.094 3RD MAX 1-HR .096

.060 .073
.084
.067
.079
.092 4TH MAX 1-HR DAY MAX>/= 0.125 0 0 0
0
0
0
0 EST DAYS>/= .125 0.0 0.0 0.0
0.0
0.0
0.0
0.0 MISS DAYS< 0.125 2 0 0
0
0
0

4Mar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 8 of 9 44201 44201 44201 019

047 091 INSTRUMENTAL

INSTRUMENTAL INSTRUMENTAL ULTRA VIOLET ULTRA VIOLET ULTRAVIOLET RADIATION ABSORBTN PARAMETER METHOD

CODE COLLECTION METHOD ANALYSIS METHOD METHODS USED IN THIS REPORTMar. 3, 2011

Note: The * indicates that the mean does not satisfy summary criteria. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)

Page 9 of 9 PQAOS USED IN THIS REPORT
PQAO AGENCY DESCRIPTION 1002 State Of Maryland Air Management AdministrationUser ID: PFB QUICKLOOK CRITERIA PARAMETERS Report Request ID: 937336 Report Code: AMP450 GEOGRAPHIC SELECTIONS Tribal

Code State County Site Parameter POC City AQCR UAR CBSA CSA EPA Region 24 510 0054 24 003 0014 24 005 1007 24 005 3001 24 013 0001 24 025 1001 24 025 9001 PROTOCOL SELECTIONS Parameter Classification

QUICK LOOK Parameter Method 44201 SELECTED OPTIONS Option Type EVENTS PROCESSING

MERGE PDF FILES WORKFILE DELIMITER

GLOBAL DATES Start Date End Date 2011 2011 Duration
Option Value EXCLUDE REGIONALLY CONCURRED EVENTS YES 1 2 3 4 5 6 7

Selection Critetia Page 1 Method Duration

SORT ORDER Column PARAMETER_CODE STATE_CODE COUNTY_CODE

SITE_ID

POC DATES' Begin Date

APPLICABLE STANDARDS Standard Description Ozone I-hour Daily 2005 Ozone 8-Hour 2008 Dec. 13, 2011
End DateDESCRIPTION o NO EVENTS 1 EVENTS EXCLUDED 2 EVENTS INCLUDED AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450)
EXCEPTIONAL DATA TYPES

5 EVENTS WITH CONCURRENCE EXCLUDED

Note: The * indicates that the mean does not satisfy summary criteria. Page 1 of 5 Dec. 13, 2011Ozone (44201) I-HOUR P 0 SITE ID C PQAO CITY COUNTY 24-003-0014 1 1002 Not in a city Anne Arundel

24-005-1007 1 1002 Cockeysville Baltimore
24-005-3001 1 1002 Essex Baltimore 24-013-0001 1 1002 Not in a city Carroll 24-025-1001 1 1002 Edgewood Harford

24-025-9001 1 1002 Not in a city Harford 24-510-0054 1 1002 Baltimore Baltimore

Note: The * indicates that the mean does not satisfy summary criteria. ,(City) AIR QUALITY SYSTEM QUICK,LOOK REPORT (AMP450) Maryland VALID DAYp ADDRESS YEAR METH MEAS Davidsonville 2011 047 208 Recreation Center, 3801 Queen Anne Bridge Road Padonia 2011 091 195 Elementary School, 9834 Greenside Drive 600 Dorsey 2011 047 203 Avenue noo w. Old 2011 047 2)0 Liberty Road

Edgewood 2011 091 209 Chemical Biological Center (APG) , Waehli Road 3560 Aldino 2011 047 201 Road Furley E.S. 2011 091 203 Recreational Center, 4633 Furley Avenue.

Page 2 of 5' Dec. 13, 2011 Parts per million (007) NUM 1ST 2ND 3RD 4TH DAY EST MISS DAYS MAX MAX MAX MAX MAX> !lAYS> DAYS< REQ I-HR I-HR I-HR I-HR STD STD STD CERT EDT 214 .111 .110 .102 .098 0 0.,0 1 0

214 .113 .103 .103 .094 0 0.0 2 0
214 .112 .109 .106 .103 0 0.0 6 0 214 .099 .089 .085 .085 0 0.0 2 0 214 .131 .121 .118 .118 1 1.0 3 0

214 .114 .114 .113 .108 0 0.0 2 0 214 .107 .106 .094 .092 0 0.0 1 0Ozone (44201) 8-HOUR P 0 SITE ID C PQAO CITY COUNTY 24-003-0014 1 1002 Not in a city Anne Arundel

24-005-1007 1 1002 Cockeysville Baltimore
24-005-3001 1 1002 Essex Baltimore 24-013-0001 1 1002 Not in'a city Carroll 24-025-1001 1 1002 Edgewood Harford

24'-025-9001 1 1002 Not in a city Harford 24-510-0054 1 1002 Baltimore Baltimore

Note: The * indicates that the mean does not satisfy summary criteria. (City) AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450) Maryland

ADDRESS YEAR METH %OBS Davidsonville 2011 047 96 Recreation Center, 3801 Queen Anne Bridge Road Padonia 2011 091 90 Elementary School, 9834 Greenside Drive 600 Dorsey 2011 047 96 Avenue 1300 W. Old 2011 047 97 Liberty Road

Edgewood. 2011 091 96 Chemical Biological Center (APG) , Waehli Road 3560 Aldino 2011 047 93 Road Furley E.S. 2011 091 95 Recreational Center, 4633 Furley Avenue.

Page 3 of 5 Dec. 13, 2011 Parts per million ( 007) VALID NUM 1ST 2ND 3RD 4TH DAY DAYS DAYS MAX MAX MAX MAX MAX> MEAS REQ 8-HR 8-HR 8-HR 8-HR STD CERT EDT

206 214 .094 .092 .088 .087 11 0

193 214 .092 .088 .086 .086 9 0
205 214 .101 .091 .087 .085 12 0 208 214 .085 .080 .079 .079 5 0 206 214 .114 .107 . 10 9 .098 17 0

199 214 .098 .090 .088 .085 13 0 203 214 .087 .084 .083 .082 7 0PARAMETER 44201 44201 METHOD CODE 047 091

Note: The * indicates that the mean does not satisfy summary criteria'. I AIR QUALITY SYSTEM QUICK LdoK REPORT (AMP450)

I METHODS USED IN THIS REPORT COLLECTION METHOD INSTRUMENTAL INSTRUMENTAL

Page 4 of 5 Dec. 13, 2011

ANALYSIS METHOD ULTRA VIOLET ULTRAVIOLET RADIATION ABSORBTNPQAO 1002

Note: The * indicates that the mean does not satisfy summary criteria. AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450) PQAO$ USED IN THIS REPORT
AGENCY DESCRIPTION State Of Maryland Air Management Administration

Page 5 of 5 Dec. 13, 2011

### APPENDIX B To: Determination of Failure to Attain by 2005 and Determination of Attainment by 2008 for the 1 - Hour Ozone National Ambient Air Quality Standards in the Baltimore Nonattainment Area in Maryland [EPA - R03 - OAR - 2011 - 0680] Appended in this appendi x are copies of: A December 30, 2003, notice of proposed rulemaking (68 FR 75191), A February 13, 2004, final rulemaking notice (69 FR 7133), A January 7, 2010, notice of proposed rulemaking (75 FR 958), and A June 4, 2010, final rulemaking notice (75 FR 31709).

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