2019-27275. Air Plan Approval; Washington; Wallula Second 10-Year Maintenance Plan  

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    AGENCY:

    Environmental Protection Agency (EPA).

    ACTION:

    Proposed rule.

    SUMMARY:

    The Environmental Protection Agency (EPA) is proposing to approve a plan for the Wallula area in Washington State that addresses the second 10-year maintenance period for particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM10). This plan relies upon the control measures contained in the first 10-year maintenance plan, with revisions to reflect updated permits and agreements, also proposed for approval in this action. Lastly, we are proposing to take final agency action on high wind and wildfire exceptional events associated with the Wallula area.

    DATES:

    Written comments must be received on or before January 21, 2020.

    ADDRESSES:

    Submit your comments, identified by Docket ID No. EPA-R10-OAR-2019-0669, at https://www.regulations.gov. Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission (i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https://www.epa.gov/​dockets/​commenting-epa-dockets.

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    FOR FURTHER INFORMATION CONTACT:

    Jeff Hunt, EPA Region 10, 1200 Sixth Avenue—Suite 155, Seattle, WA 98101, at (206) 553-0256, or hunt.jeff@epa.gov.

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    SUPPLEMENTARY INFORMATION:

    Throughout this document whenever “we,” “us,” or “our” is used, it is intended to refer to the EPA. This supplementary information section is arranged as follows:

    Table of Contents

    I. Background

    II. Requirements of a Maintenance Plan

    III. Analysis of Washington's Submission

    A. Attainment Emissions Inventory

    B. Maintenance Demonstration

    C. Monitoring Network

    D. Verification of Continued Attainment

    E. Contingency ProvisionsStart Printed Page 70131

    IV. Proposed Actions

    V. Incorporation by Reference

    VI. Statutory and Executive Order Reviews

    I. Background

    The Wallula area lies in eastern Washington near the Oregon border in the southern portion of the Columbia Plateau. The area is comprised of parts of Walla Walla and Benton Counties and a small portion of Sacajawea State Park in Franklin County. It is generally rural and agricultural. Prominent land uses include dryland and irrigated cropland, industrial sites, and natural vegetation. There is one major stationary source located in the Wallula area, Boise Paper Wallula Mill (a division of Packaging Corporation of America), a large pulp and paper mill and associated compost facility and landfill. There is also a large beef cattle feedlot, a beef processing plant, a natural gas compressor station, grain storage silos, and a few other minor sources. The Wallula area is in the lowest and driest section of eastern Washington and receives as little as seven to nine inches of precipitation each year. The surrounding Columbia Plateau is known for prolonged periods of strong winds which carry dust particles for hundreds of miles downwind. Wind erosion is a problem throughout the Columbia Plateau, due to its dry environment, scant vegetation, unpredictable high winds, and soils which contain substantial quantities of PM10.

    The Wallula area was designated nonattainment for the 24-hour PM10 national ambient air quality standards (NAAQS) and classified as a Moderate area upon enactment of the Clean Air Act Amendments of 1990 (56 FR 56694, November 6, 1991). The Washington Department of Ecology (Ecology) submitted a Moderate area attainment plan for the Wallula area on November 13, 1991, and a Serious area plan on November 30, 2004. The EPA acted on the plans on January 27, 1997, and May 2, 2005, respectively (62 FR 3800 and 83 FR 22597). During the planning process, the EPA determined that the area attained the PM10 NAAQS based on 1999 through 2001 air quality monitoring data (67 FR 64815, October 22, 2002).

    As discussed in the EPA's finding of attainment and the state's attainment plan submissions, windblown dust during high wind events is a significant contributor to exceedances of the PM10 NAAQS in the Wallula area. Under the Clean Air Act, specific exceedances due to natural events, such as unusually high winds, may be discounted or excluded entirely from decisions regarding an area's air quality status in appropriate circumstances. From 1996 to 2007, EPA's Natural Events Policy [1] governed the process by which states could request exclusion of monitored values that exceeded the NAAQS due to “natural events” in making attainment determinations. As part of the EPA's finding of attainment for the Wallula area in 2002, the EPA determined that all exceedances that occurred in 1999 through 2001 qualified as high wind natural events under the EPA's Natural Events Policy. (67 FR 64815, October 22, 2002).

    Subsequently, Ecology conducted a final review of high wind natural events for the area and provided the EPA information in support of the state's maintenance plan and request to redesignate the Wallula area, submitted on March 29, 2005. Ecology found that there had been nine reported PM10 exceedances in the Wallula area since January 1, 1995, and all but one was reasonably attributed to dust raised by unusually high winds.[2] The EPA approved the submitted maintenance plan and redesignation request on August 26, 2005 (70 FR 50212). This maintenance plan covered the first 10-year period and demonstrated, after excluding the high wind natural events under EPA's Natural Events Policy, that the existing control measures approved in the Moderate and Serious attainment plans were adequate to maintain the PM10 NAAQS.

    II. Requirements of a Maintenance Plan

    Section 175A of the Clean Air Act sets forth the elements of a maintenance plan. Under section 175A, a state must submit a plan to demonstrate continued attainment of the applicable NAAQS for at least 10 years after an area is redesignated to attainment. For Wallula, this initial maintenance period was 2005 through 2015. The state must then submit a revised maintenance plan demonstrating that the area will continue to attain for the 10 years following the initial 10-year period. For Wallula, this period is 2015 through 2025. The EPA's Calcagni memorandum contains a list of core provisions the EPA anticipates to be necessary to ensure maintenance of the relevant NAAQS.[3] The memorandum recommends that a maintenance plan address the following provisions: (1) An attainment emissions inventory; (2) a demonstration showing maintenance for 10 years; (3) a commitment to maintain the existing monitoring network; (4) verification of continued attainment; and (5) a contingency plan to prevent or correct future violations of the NAAQS. Washington's SIP submission discusses each of these elements.

    III. Analysis of Washington's Submission

    A. Attainment Emissions Inventory

    Washington's second 10-year maintenance plan for the Wallula area includes a 2014 attainment emissions inventory, which is the most up to date emissions information available as part of the National Emissions Inventory (NEI) process. The EPA has reviewed the procedures used to develop the 2014 attainment emissions inventory and we find them to be reasonable and approvable. The overall source mix and emissions levels are generally consistent with the 2002 attainment emissions inventory contained in the first 10-year maintenance plan. While there has been some increase in emissions activity since 2002, Ecology explained and the EPA verified that much of the difference between the 2002 and 2014 inventories is due to revised emissions inventory methodology. For example, Ecology revised the emissions factor for cattle feedlots by increasing it approximately eightfold, a conservative approach.[4] Based on the most up-to-date emissions inventory information, Ecology calculated the source mix for a typical PM10 season day in the maintenance area, which occurs from June through October. The main emissions sources in the area during this season include agricultural tilling and harvesting in aggregate (43%), Simplot Feeders (18%), and Boise White Paper (10%). Other smaller point sources, such as road dust, construction dust, and motor vehicles comprise the remaining emissions source categories.[5]

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    B. Maintenance Demonstration

    To demonstrate maintenance, emissions inventories are projected to future dates to assess the influence of changes in growth and controls. These inventories show actual emissions in pounds per season day equal to 6,334 pounds in 2014, and projected inventories of 8,519 pounds in 2020, and 8,599 pounds in 2025. As discussed in the submission, Ecology used a conservative projection methodology including highest actual emissions, potential to emit, and maximum permitted capacity, as appropriate, in developing the 2020 and 2025 projections.[6] These projections would be expected to represent an upper bound of potential, future emissions, explaining the difference between the 2014 actual emissions and possible growth in 2020 and 2025.

    Because the 2020 and 2025 projected emissions inventories are greater than the 2014 attainment inventory, Ecology conducted a roll forward analysis to demonstrate that the Wallula area will continue to remain in attainment through the year 2025. To perform the roll forward modeling, Ecology calculated a three-year design concentration using 2012 through 2014 monitoring data.[7] This 2014 design concentration, equaling 112 micrograms per cubic meter (μg/m3), corresponds to the 2014 attainment emission inventory. Ecology then modeled how the potential emissions growth might impact future PM10 design concentrations. The maximum modeled 2025 design concentration, using the most conservative methodology, was 145 μg/m3, below the level of the 24-hour PM10 NAAQS of 150 μg/m3. For comparison, if a less conservative methodology is used, factoring in potential natural events and using maximum 5-year actual rather than maximum allowable permit limits, the projected 2025 design concentration would be 82 μg/m3. As shown in Table 20 of the second 10-year plan, this projected 2025 design concentration is generally consistent with recent design concentrations after factoring in the effect of natural events.

    The Calcagni memorandum explains that states are expected to maintain implemented control strategies unless such measures are shown to be unnecessary for maintenance or replaced with measures that achieve equivalent reductions. Ecology retained all control measures cited in the first 10-year maintenance plan; however, some changed over time since the EPA's last approval on May 2, 2005 (70 FR 22597). For example, in 2018, Ecology and Simplot Feeders updated the “Fugitive Dust Control Plan for Simplot Feeders” originally approved into the SIP in 2005 (70 FR 22597, May 2, 2005). The updated fugitive dust control plan was developed to prevent dust from any fugitive or point sources from crossing the Simplot property line. The updated fugitive dust control plan requires road dust suppression, better staff training, daily observations, and daily adaptive best management practices to make sure potential fugitive dust emissions are controlled. In a related 2018 update, Ecology negotiated an update to the 1995 “Fugitive Dust Control Guidelines for Beef Cattle Feedlots and Best Management Practices” with the Washington Cattlemen's Association, last approved into the SIP in 2005 (70 FR 22597, May 2, 2005). Ecology requested that both updated agreements replace the prior versions currently approved in the SIP.

    The first 10-year maintenance plan also included site-specific permits and orders for Boise White Paper and Tyson Fresh Meats (formerly IBP). The SIP-approved order for Boise White Paper (Order No. 1614-AQ04), and the dust control plan for the associated landfill, remain unchanged since the EPA's approval in 2005 (70 FR 22597, May 2, 2005). However, the SIP-approved Title V air operating permit for Boise White Paper, which cites the order and dust control plan as a permit condition, has since expired. Ecology requested that the EPA replace the expired 2004 permit in the SIP with the recently-issued 2018 version. The 2018 version retains permit condition Q.1 requiring compliance with the existing order and fugitive dust plan (a copy of the 2018 permit is included in the docket).

    In a notice of construction (NOC) approval order, issued by Ecology in 2002 and approved into the SIP in 2005, Tyson Fresh Meats (formerly IBP) requested a PM10 emission limitation to remain below the 70 ton per year threshold for a major source in a Serious PM10 nonattainment area (02AQER-5074). In 2007, Tyson Fresh Meats submitted a notice of construction application to increase hourly slaughter rates and add two new cookers. In the technical support document (TSD) amending the SIP-approved Order, Ecology determined the emissions increase would be minimal, with an estimated increase of 0.05 pounds per hour and no increase on annual basis. In implementing the new source review provisions of Chapter 173-400 Washington Administrative Code, Ecology determined that the change would not cause or contribute to violations of the NAAQS. Ecology's TSD and the 2007 amended NOC approval order are included in the docket for this action.

    In 2014, Ecology consolidated the air permits for Tyson Fresh Meats into one comprehensive permit, including the permit conditions contained in amended Order 02AQER-5074 (a copy of the consolidated 2014 order is included in the docket for this action). This was done in connection with a request from Tyson to remove propane as a backup fuel for the boilers and not using tallow as a fuel for the boilers and dryers. The TSD for the 2007 permit revision states that, with these changes in allowable fuels, potential to emit PM10 is reduced to 27.10 tons per year, well below the 70 tons per year emissions limitation established in the 2002 NOC order of approval, such that Tyson is now a true minor source rather than a synthetic minor source for Title V. The limits on particulate matter from amended Order 02AQER-5074 (currently approved in the SIP), however, remain in effect and are included in the 2014 consolidated permit. Ecology submitted, and the EPA is proposing to approve in the SIP, the updated 2014 permit conditions and related monitoring, recordkeeping, and reporting that replace the permit conditions contained in the 2002 NOC order of approval. Because many of the permit conditions contained in the 2014 consolidated permit are unrelated to the original 2002 SIP-approved NOC order of approval or are not required elements for SIP incorporation, a strikeout version of the exact permit conditions proposed for approval is included in the docket for this action.

    C. Monitoring Network

    Washington's maintenance plan includes a commitment to continue to operate its EPA-approved monitoring network to demonstrate compliance with the PM10 NAAQS for the Wallula area. On June 28, 2018, Ecology submitted the 2018 Annual Monitoring Network Plan, which the EPA approved on August 13, 2018. Ecology's network plan and the EPA's approval letter are included in the docket for this action. Any changes to the PM10 monitoring network for the Wallula area must be made in accordance with the requirements of 40 CFR part 58 and approved by the EPA as part of the annual monitoring network plan process.Start Printed Page 70133

    D. Verification of Continued Attainment

    The level of the PM10 NAAQS is 150 micrograms per cubic meter (μg/m3), 24-hour average concentration. The NAAQS is attained when the expected number of days per calendar year with a 24-hour average concentration above 150 μg/m3 is equal to or less than one. (40 CFR 50.6). Under the approved first 10-year maintenance plan, verification of continued attainment was addressed through operation of an appropriate air quality monitoring network. In developing the second 10-year maintenance plan, Washington evaluated the most recent three years of complete, quality-assured data for the Wallula area (2015 through 2017) to verify continued attainment of the standard.

    As previously discussed, the Clean Air Act allows the exclusion of certain event-affected air quality data. This process is currently implemented under the Exceptional Events Rule (codified at 40 CFR 50.1, 50.14, and 51.930). Under the EPA's Exceptional Events Rule process, Ecology flagged six exceedances of the PM10 NAAQS during the 2015 through 2017 monitoring period as potential exceptional events. Three of the flagged exceedances were associated with unusually high wind events that entrained dust (August 14, 2015, October 30, 2015, and November 17, 2015). As discussed in Ecology's submission, this entrained dust primarily originated in the Horse Heaven Hills area, located approximately 70 miles from the maintenance area, as well as other Columbia Plateau counties, such as Franklin and Adams Counties. An additional three days in 2017 were flagged as wildfire-influenced data, with numerous active fires occurring throughout Washington, Oregon, and western Canada on those days (September 5 through 7, 2017). The Exceptional Events Rule recommends that states submit exceptional event demonstrations only for exceedances “flagged” as due to exceptional events that have regulatory significance. Consistent with this recommendation, Ecology submitted one exceptional event demonstration on November 30, 2017, to request exclusion of the August 14, 2015, high wind event data. On March 20, 2019, Ecology submitted a second exceptional event demonstration to exclude the wildfire influenced data on September 5 through 7, 2017.

    The EPA evaluated Ecology's exceptional event demonstrations for August 14, 2015, and September 5 through 7, 2017, with respect to the requirements of the EPA's Exceptional Events Rule. On March 21, 2018, the EPA concurred with Ecology's request to exclude event-influenced data for August 14, 2015. On September 11, 2019, we concurred with Ecology's request to exclude the wildfire event-influenced data for September 5 and 6, 2017. We note that, although Ecology's exceptional event demonstration included September 7, 2017, it was not necessary for the EPA to concur on this day because the area showed attainment of the 24-hour PM10 NAAQS with the exclusion of September 5 and 6, 2017, data. The EPA concurrence letters explain how Ecology met the criteria in the Exceptional Events Rule to demonstrate that the August 14, 2015, and September 5 and 6, 2017, exceedances qualify as exceedances attributable to exceptional events. The EPA now proposes to take final agency action on Ecology's request to exclude data from August 14, 2015, and September 5 and 6, 2017. Exclusion of the event-influenced data yields a three-year average of 1.0 expected exceedances for 2015 through 2017, equal to the threshold of 1.0 to demonstrate attainment of the 24-hour PM10 NAAQS. For further information, refer to Ecology's exceptional event demonstration packages and the EPA's concurrence and analysis located in the docket for this action.

    E. Contingency Provisions

    Due to the unique nature of the Wallula area, with nearly all exceedances since 1995 associated with high wind or wildfire events, the first 10-year maintenance plan contingency provisions relied heavily on the “Columbia Plateau Windblown Dust Natural Events Action Plan” (NEAP) approved into the SIP in 2005. The NEAP focuses on agricultural sources, primarily outside the maintenance area, encouraging ongoing participation in U.S. Department of Agriculture soil conservation programs. The NEAP remains unchanged in the SIP since the first 10-year maintenance plan. However, to comply with the EPA's revisions to the Exceptional Events Rule, Ecology submitted a mitigation plan to support future evaluation of exceptional events in the Wallula area, supplementing the SIP-approved NEAP. The Exceptional Events Rule notes that mitigation plans are not required to be submitted as part of the SIP but are evaluated as part of the ongoing EPA and state coordination on exceptional events. The current mitigation plan is included in the docket for this action as well as the EPA's November 21, 2019, letter approving Ecology's mitigation plan. In light of the exceptional event considerations discussed above, Ecology is retaining, unchanged the contingency provisions approved in the first 10-year maintenance plan.

    IV. Proposed Actions

    The EPA is proposing to approve Ecology's second 10-year maintenance plan for the 24-hour PM10 Wallula area as satisfying the requirements of section 175A of the Clean Air Act. We are also proposing to take final agency action on Ecology's request to exclude wildfire and high wind event-influenced data from August 14, 2015, and September 5 and 6, 2017. In addition, we are proposing to approve, and incorporate into the SIP at 40 CFR part 52.2470(d), the updated source-specific requirements for Tyson Fresh Meats, Boise White Paper, and Simplot Feeders shown in Table 1, below.

    Table 1—State Source-Specific Requirements Proposed for Approval

    Name of sourceOrder/Permit No.State effective dateExplanations
    Tyson Fresh Meats, Inc13AQ-E5264/16/2014Except:
    1. Decontamination Cabinets;
    2. Meat Cutting/Packing;
    6. Wastewater Floatation;
    8. Utility Equipment;
    10. Other;
    References to “WAC 173-460-040” in “Determinations”;
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    The portion of Approval Condition 2.a which states, “and consumption of no more than 128 million cubic feet/of natural gas per year. Natural gas consumption records for the dryer shall be maintained for the most recent 24 month period and be available to Ecology for inspection. An increase in natural gas consumption that exceeds the above level may require a Notice of Construction.”;
    Approval Condition 3;
    Approval Condition 4;
    Approval Condition 5;
    Approval Condition 6.e;
    Approval Condition 9.a.ii;
    Approval Condition 9.a.iv;
    Approval Condition 9.a.v;
    Approval Condition 9.a.vi;
    Approval Condition 10.a.ii;
    Approval Condition 10.b;
    Approval Condition 11.a;
    Approval Condition 11.b;
    Approval Condition 11.e;
    Approval Condition 12;
    Approval Condition 15;
    The section titled “Your Right to Appeal”; and
    The section titled “Address and Location Information.”
    Boise White Paper L.L.C00036974/1/2018Condition Q.1 only.
    Simplot Feeders Limited PartnershipFugitive Dust Control Plan3/1/2018

    In addition, we are proposing to update the list of supplementary documents in 40 CFR part 52.2470(e) to include the 2003 “Columbia Plateau Windblown Dust Natural Events Action Plan” and Ecology's 2018 update of the “Fugitive Dust Control Guidelines for Beef Cattle Feedlots and Best Management Practices.”

    Finally, we are proposing to take final agency action on high wind and wildfire exceptional events associated with the Wallula area and determine that the PM10 exceedances on the identified dates were due to exceptional events and can be excluded in determining the attainment status of the area.

    V. Incorporation by Reference

    In this document, the EPA is proposing to include regulatory text in an EPA final rule that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, the EPA is proposing to incorporate by reference in 40 CFR part 52.2470(d) the updated source-specific requirements shown in section IV at Table 1 of this preamble. The EPA has made, and will continue to make, these materials generally available through www.regulations.gov and at the EPA Region X Office (please contact the person identified in the FOR FURTHER INFORMATION CONTACT section of this preamble for more information).

    VI. Statutory and Executive Order Reviews

    Under the Clean Air Act, the Administrator is required to approve a SIP submission that complies with the provisions of the Act and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, the EPA's role is to approve state choices, provided that they meet the criteria of the Clean Air Act. Accordingly, this action merely proposes to approve state law as meeting federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this action:

    • Is not a “significant regulatory action” subject to review by the Office of Management and Budget under Executive Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
    • Is not an Executive Order 13771 (82 FR 9339, February 2, 2017) regulatory action because SIP approvals are exempted under Executive Order 12866;
    • Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
    • Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
    • Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
    • Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);
    • Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);
    • Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);
    • Is not subject to requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because this action does not involve technical standards; and
    • Does not provide the EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

    The SIP is not approved to apply on any Indian reservation land, or any other area where the EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, the rule does not have tribal implications and will not impose substantial direct costs on tribal Start Printed Page 70135governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

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    List of Subjects in 40 CFR Part 52

    • Environmental protection
    • Air pollution control
    • Incorporation by reference
    • Intergovernmental relations
    • Particulate matter, and Reporting and recordkeeping requirements
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    Authority: 42 U.S.C. 7401 et seq.

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    Dated: December 2, 2019.

    Chris Hladick,

    Regional Administrator, Region 10.

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    Footnotes

    1.  See Memorandum from the EPA's Assistant Administrator for Air and Radiation to EPA Regional Air Directors entitled “Areas Affected by Natural Events,” dated May 30, 1996 (EPA's Natural Events Policy), in effect at that time.

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    2.  The one exceedance not attributed to high winds occurred on July 3, 1997, and was attributed to an unusual and nonrecurring activity involving the transport of multiple loads of composting material near the monitor.

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    3.  See Memorandum from the EPA's Air Quality Management Division Director to EPA Regional Air Directors entitled “Procedures for Processing Requests to Redesignate Areas to Attainment,” dated September 4, 1992 (Calcagni memorandum).

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    4.  Bonifacio, H.M. (2012). Particulate matter emission rates from beef cattle feedlots in Kansas—Reverse dispersion modeling. Journal of the Air & Waste Management Association, 62(3), 62(3), pp.350-361.

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    5.  Onroad motor vehicles are approximately 1% of the overall inventory. As part of the serious area attainment plan approval, the EPA granted Washington's request for an exemption from regional analysis for transportation conformity because motor vehicles were an insignificant source of PM10 emissions.

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    6.  See Emissions Inventory Documentation for the Wallula PM10 Second 10-Year Maintenance Plan.

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    7.  See PM10 design concentration table look-up method, page 6-3, PM10 SIP Development Guideline.

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    [FR Doc. 2019-27275 Filed 12-19-19; 8:45 am]

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