AGENCY:
Environmental Protection Agency (EPA).
ACTION:
Proposed rule.
SUMMARY:
On September 29, 2017, the Idaho Department of Environmental Quality (IDEQ) submitted a redesignation request and limited maintenance plan (LMP) for particulate matter with an aerodynamic diameter less than or equal to ten micrometers (PM10) for the PM10 National Ambient Air Quality Standard (NAAQS) developed for the Pinehurst PM10 Nonattainment Area (NAA) and Pinehurst PM10 Expansion Nonattainment Area (NAA). The redesignation request asserts that the area meets the Clean Air Act (CAA) requirements for redesignation identified in section 107(d)(3)(E). This limited maintenance plan for these contiguous nonattainment areas addresses maintenance of the PM10 standard for a ten-year period beyond redesignation. The Environmental Protection Agency (EPA) proposes to approve this IDEQ Implementation Plan (SIP) revision. The EPA also proposes to approve the September 15, 2013, high wind exceptional event at the Pinehurst monitoring station. Additionally, the EPA is proposing to approve the emissions inventory for the West Silver Valley annual PM2.5 NAA.
DATES:
Written comments must be received on or before June 11, 2018.
ADDRESSES:
Submit your comments, identified by Docket ID No. EPA-R10-OAR-2017-0582, at http://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 http://www2.epa.gov/dockets/commenting-epa-dockets.
FOR FURTHER INFORMATION CONTACT:
Justin Spenillo, Air Planning Unit, Office of Air and Waste (OAW-150), Environmental Protection Agency, Region 10, 1200 Sixth Ave., Suite 900, Seattle, WA 98101; telephone number: 206-553-6125, email address: spenillo.justin@epa.gov.
SUPPLEMENTARY INFORMATION:
Throughout this document, wherever “we”, “us” or “our” are used, it is intended to refer to the EPA.
Table of Contents
I. This Action
II. Background
A. PM10 NAAQS
B. Pinehurst PM10 NAA and Planning Background
III. Requirements for Redesignation
A. CAA Requirements for Redesignation of Nonattainment Area
B. The LMP Option for PM10 Nonattainment Areas
C. Conformity Under the LMP Option
IV. Review of the Idaho Submittal Addressing the Requirements for Redesignation and LMPs
A. Has the Pinehurst PM10 NAA attained the applicable NAAQS?
B. Does the Pinehurst PM10 NAA have a fully approved SIP under section 110(k) of the CAA?
C. Has the IDEQ met all applicable requirements under section 110 and Part D of the CAA?
D. Has the IDEQ demonstrated that the air quality improvement is due to permanent and enforceable reductions?
E. Does the area have a fully approved maintenance plan pursuant to section 175A of the CAA?
F. Has the IDEQ demonstrated that the Pinehurst PM10 NAA qualifies for the LMP Option?
G. Does the IDEQ have an approved attainment emissions inventory which can be used to demonstrate attainment of the NAAQS?
H. Does the LMP include an assurance of continued operation of an appropriate EPA-approved air quality monitoring network, in accordance with 40 CFR part 58?
I. Does the plan meet the clean air act requirements for contingency provisions?
J. How is conformity treated under a limited maintenance plan?
V. 2013 p.m.10 High Wind Exceptional Event
VI. West Silver Valley 2012 Annual PM2.5 Emission Inventory
A. Requirements for Emissions Inventories
B. West Silver Valley PM2.5 Base Year Emissions Inventory
C. EPA's Evaluation
VII. Proposed Action
VIII. Statutory and Executive Order Reviews
I. This Action
The EPA is proposing to approve the limited maintenance plan (LMP) submitted by the Idaho Department of Environmental Quality (IDEQ) on September 29, 2017, for the Pinehurst PM10 Nonattainment Area (NAA) and Pinehurst PM10 Expansion NAA and to concurrently redesignate the areas to attainment for the PM10 National Ambient Air Quality Standard (NAAQS). Throughout this notice, Pinehurst PM10 NAA shall refer to both the original Pinehurst PM10 NAA and Pinehurst PM10 Expansion NAA unless noted otherwise. The EPA has reviewed air quality data for the area and determined that the Pinehurst NAA attained the PM10 NAAQS by the required attainment date, and that monitoring data continue to show attainment. The EPA is proposing to approve exclusion of data from a high wind exceptional event on September 15, 2013, that impacted PM10 values at the Pinehurst monitor as they are needed to meet the LMP criteria. Separately, the EPA is proposing to approve the base year emission inventory for the West Silver Valley (WSV) PM2.5 NAA in the Silver Valley, Idaho.
II. Background
A. PM 10 NAAQS
“Particulate matter,” also known as particle pollution or PM, is a complex mixture of extremely small particles and liquid droplets. The size of particles is directly linked to their potential for causing health problems. The EPA is concerned about particles that are 10 micrometers in diameter or smaller because those are the particles that generally pass through the throat and nose and enter the lungs. Once inhaled, these particles can affect the heart and lungs and can cause serious adverse health effects. People with heart or lung diseases, children and older adults are the most likely to be affected by particle pollution exposure. Healthy individuals may also experience temporary symptoms from exposure to elevated levels of particle pollution.
On July 1, 1987, the EPA promulgated a NAAQS for PM10 (52 FR 24634). The EPA established a 24-hour standard of 150 µg/m3 and an annual standard of 50 µg/m3, expressed as an annual arithmetic mean. The EPA also promulgated secondary PM10 standards that were identical to the primary standards. In a rulemaking action dated October 17, 2006, the EPA retained the 24-hour PM10 standard but revoked the annual PM10 standard (71 FR 61144, effective December 18, 2006).
B. Pinehurst PM 10 NAA and Planning Background
On July 1, 1987, the EPA promulgated the PM10 NAAQS (52 FR 24634) and on August 7, 1987, the EPA identified the Pinehurst area as a “Group I” area with a strong likelihood of violating the NAAQS (52 FR 29383). On March 15, 1991, the EPA published a notice announcing that the Pinehurst area had been designated a PM10 NAA upon the November 15, 1990 enactment of the 1990 CAA Amendments. In this notice, the EPA identified that the IDEQ needed to develop and submit by November 15, 1991, a plan that would bring the area into attainment by no later than December 31, 1994 (56 FR 11101). On November 6, 1991, the Pinehurst PM10 NAA, which included the City of Pinehurst, was classified as moderate under sections 107(d)(4)(B) and 188(a) of the CAA (56 FR 56694), and it had an attainment date of no later than December 31, 1994. On December 21, 1993, the EPA designated the Pinehurst PM10 Expansion NAA, a contiguous area to the south of the City of Pinehurst and the existing Pinehurst PM10 NAA; the action became effective January 20, 1994 (58 FR 67334). The Pinehurst Expansion area had an attainment date no later than December 31, 2000. These two nonattainment areas, while contiguous and share common planning elements, have separate timing requirements and are considered separate nonattainment areas.
After these designations to nonattainment for the Pinehurst PM10 NAA, the IDEQ worked with the community of Pinehurst to develop a plan to bring the Pinehurst PM10 NAA into attainment. The IDEQ submitted a plan for the Pinehurst PM10 NAA, both the original and expansion areas, to the EPA on April 14, 1992, as a moderate PM10 State Implementation Plan (SIP) under section 189(a) of the CAA. The IDEQ's submitted plan addressed PM10 reductions through a suite of measures aimed at reducing wood smoke, primarily through a program to replace woodstoves with cleaner burning devices. The EPA conditionally approved the IDEQ's moderate PM10 SIP applicable to the City of Pinehurst on August 25, 1994 (59 FR 43745) and conditionally approved the revisions applicable to the Pinehurst PM10 Expansion area on May 26, 1995 (60 FR 27891). Both plans were conditionally approved because these areas had failed to submit contingency measures. The IDEQ submitted a contingency plan covering both areas on July 13, 1995, which the EPA subsequently approved on October 2, 2014 (79 FR 59435). On August 23, 2001, the EPA published a finding that the two areas had attained the PM10 standard by their respective attainment dates (66 FR 44304).
The IDEQ prepared a LMP for the Pinehurst PM10 NAA and provided notice and an opportunity for public comment on the proposed plan. On September 29, 2017, the IDEQ submitted the Pinehurst PM10 LMP to EPA for approval and has requested that the EPA redesignate the Pinehurst NAA to attainment for the PM10 NAAQS.
III. Requirements for Redesignation
A. CAA Requirements for Redesignation of Nonattainment Area
A nonattainment area can be redesignated to attainment after the area has measured air quality data showing the NAAQS has been attained and when certain planning requirements are met. Section 107(d)(3)(E) of the CAA, and the General Preamble to Title I provide the criteria for redesignation (57 FR 13498, April 16, 1992). These criteria are further clarified in a policy and guidance memorandum from John Calcagni, Director, Air Quality Management Division, EPA Office of Air Quality Planning and Standards dated September 4, 1992, entitled “Procedures for Processing Requests to Redesignate Areas to Attainment” (Calcagni memo). The criteria for redesignation are:
1. The Administrator has determined that the area has attained the applicable NAAQS;
2. The Administrator has fully approved the applicable SIP for the area under section 110(k) of the CAA;
3. The state has met all requirements applicable to the area under section 110 and part D of the CAA;
4. The Administrator has determined that the improvement in air quality is due to permanent and enforceable reductions in emissions; and
5. The Administrator has fully approved a maintenance plan for the area as meeting the requirements of section 175A of the CAA.
B. The LMP Option for PM 10 Nonattainment Areas
On August 9, 2001, the EPA issued guidance on streamlined maintenance plan provisions for certain moderate PM10 nonattainment areas seeking redesignation to attainment (Memo from Lydia Wegman, Director, Air Quality Standards and Strategies Division, entitled “Limited Maintenance Plan Option for Moderate PM10 Nonattainment Areas” (LMP Option memo)). The LMP Option memo contains a statistical demonstration that areas meeting certain air quality criteria will, with a high degree of probability, maintain the standard 10 years into the future. Thus, the EPA has already provided the maintenance demonstration for areas meeting the criteria outlined in the LMP Option memo. It follows that future year emission inventories for these areas, and some of the standard analyses to determine transportation conformity with the SIP are no longer necessary.
To qualify for the LMP Option, the area should have attained the PM10 NAAQS and, based upon the most recent five years of air quality data at all monitors in the area, the 24-hour design value should be at or below 98 µg/m3. If an area cannot meet this test, it may still be able to qualify for the LMP Option if the average design value (ADV) for the site is less than the site-specific critical design value (CDV). In addition, the area should expect only limited growth in on-road motor vehicle PM10 emissions (including fugitive dust) and should have passed a motor vehicle regional emissions analysis test. The LMP Option memo also identifies core provisions that must be included in the LMP. These provisions include an attainment year emissions inventory, assurance of continued operation of an EPA-approved air quality monitoring network, and contingency provisions.
C. Conformity Under the LMP Option
The transportation conformity rule and the general conformity rule (40 CFR parts 51 and 93) apply to nonattainment areas and maintenance areas covered by an approved maintenance plan. Under either conformity rule, an acceptable method of demonstrating that a Federal action conforms to the applicable SIP is to demonstrate that expected emissions from the planned action are consistent with the emissions budget for the area.
While EPA's LMP Option does not exempt an area from the need to affirm conformity, it explains that the area may demonstrate conformity without conforming to an emissions budget. Under the LMP Option, emissions budgets are treated as essentially not constraining for the length of the maintenance period because it is unreasonable to expect that the qualifying areas would experience so much growth in that period that a violation of the PM10 NAAQS would result. For transportation conformity purposes, the EPA would conclude that emissions in these areas need not be capped for the maintenance period and therefore a regional emissions analysis would not be required. Similarly, Federal actions subject to the general conformity rule could be considered to satisfy the “budget test” specified in 40 CFR 93.158(a)(5)(i)(A) for the same reasons that the budgets are essentially considered to be unlimited.
IV. Review of the Idaho Submittal Addressing the Requirements for Redesignation and LMPs
A. Has the Pinehurst PM 10 NAA attained the applicable NAAQS?
To demonstrate that an area has attained the PM10 NAAQS, the IDEQ must submit an analysis of ambient air quality data from an ambient air monitoring network representing peak PM10 concentrations. The data should be quality-assured and stored in the EPA Air Quality System database. The EPA has reviewed air quality data for the area and has determined that the Pinehurst NAA attained the PM10 NAAQS by the applicable attainment dates of December 31, 1994 for the City of Pinehurst and December 31, 2000 for the Pinehurst PM10 Expansion area, and they continue to attain the PM10 NAAQS. EPA's analysis is described below.
Because the annual PM10 standard was revoked effective December 18, 2006, see 71 FR 61144 (October 17, 2006), this notice discusses only attainment of the 24-hour PM10 standard.”
The 24-hour PM10 NAAQS is 150 µg/m3. An area has attained this 24-hour standard when the average number of expected exceedances per year is less than or equal to one, when averaged over a three-year period (40 CFR 50.6). To make this determination, three consecutive years of complete ambient air quality data must be collected in accordance with Federal requirements (40 CFR part 58 including appendices).
A comprehensive air quality monitoring plan, meeting the requirements of 40 CFR part 58, was originally submitted by the IDEQ to the EPA on January 15, 1980, and approved by the EPA on July 28, 1982 (40 CFR 52.670), and most recently submitted in June 2017, with approval by the EPA on November 8, 2017. The monitoring plan describes the Idaho monitoring network throughout the state, which includes the Pinehurst Idaho monitor (AQS ID 16-079-0017-81102-3). In the LMP submittal, the IDEQ states that the nonattainment designation was based on data collected at the Pinehurst monitoring site. With the exception of three high wind exceptional events, a review of data shows that PM10 3-year average expected exceedances recorded at this site have been less than or equal to the 24-hour PM10 NAAQS since 1994. In addition, the IDEQ states that the Pinehurst monitoring site is operated in compliance with the EPA monitoring guidelines set forth in 40 CFR part 58, Ambient Air Quality Surveillance.
Data from the Pinehurst monitoring site has been quality assured by the IDEQ and submitted to the EPA's Air Quality System (AQS), accessible through the EPA's AirData website at https://www.epa.gov/outdoor-air-quality-data. To show attainment for the 24-hour PM10 NAAQS the three-year design value must be less than or equal to 1.0 expected number of exceedances, as established in Appendix K to 40 CFR part 50. The Pinehurst monitoring site recorded exceedances in 2013 and 2015 and the IDEQ flagged these exceedances as being the result of exceptional events where unusually high winds entrained dust. Under the EPA's Exceptional Events Rule, the Agency may exclude data from a regulatory determination related to an exceedance or violation of the NAAQS if the IDEQ adequately demonstrates that an exceptional event caused the exceedance or violation. 40 CFR 50.1 and 50.14. For the reasons set forth in the IDEQ's Pinehurst PM10 2013 High Wind Exceptional Event concurrence letter and analysis (March 2, 2017), the EPA excluded data showing an exceedance on September 15, 2013, in determining whether the Pinehurst NAA has attained the PM10 NAAQS. The concurrence letter explains how the IDEQ met the Exceptional Event Rule criteria to demonstrate that the September 15, 2013 exceedance qualifies as an exceptional event. Based on this demonstration, the IDEQ's submission demonstrates that the Pinehurst PM10 NAA's expected number of exceedances was 0.67 for 2013-15, which is below the 1.0 upper limit. The EPA confirmed that the area continues to be less than or equal to the 1.0 expected number exceedances with the 2014-16 value being 0.7. The EPA therefore finds that the area was not violating the PM10 NAAQS.
B. Does the Pinehurst PM 10 NAA have a fully approved SIP under section 110(k) of the CAA?
To qualify for redesignation, the SIP for an area must be fully approved under section 110(k) of the CAA, and must satisfy all requirements that apply to the area. As discussed in Section II.B. above, the IDEQ submitted a moderate PM10 SIP for the Pinehurst PM10 NAA on April 14, 1992. The EPA took final action to conditionally approve the IDEQ's moderate PM10 SIP on August 25, 1994 (59 FR 43745) for the City of Pinehurst and to conditionally approve the IDEQ's moderate PM10 SIP on May 26, 1995 (60 FR 27891) for the Pinehurst PM10 Expansion area. These conditional approvals required submission of contingency measures. Accordingly, the IDEQ submitted the contingency plan applicable to the entire Pinehurst PM10 NAA as required by the conditional approvals on July 13, 1995. With the EPA's approval on October 2, 2014 (79 FR 59435), the Pinehurst PM10 NAA satisfied all requirements that apply to the area and thus the area has a fully approved nonattainment area SIP under section 110(k) of the CAA.
C. Has the IDEQ met all applicable requirements under section 110 and Part D of the CAA?
Section 107(d)(3)(E) of the CAA requires that a state containing an NAA meet all applicable requirements under section 110 and Part D of the CAA for the area to be redesignated to attainment. The EPA interprets this to mean that the IDEQ must meet all requirements that applied to the area prior to, and at the time of, the submission of a complete redesignation request. The following is a summary of how Idaho meets these requirements.
1. Clean Air Act Section 110 Requirements
Section 110(a)(2) of the CAA contains general requirements for nonattainment plans. These requirements include, but are not limited to: Submittal of a SIP that has been adopted by the IDEQ after reasonable notice and public hearing; provisions for establishment and operation of appropriate apparatus, methods, systems and procedures necessary to monitor ambient air quality; implementation of a permit program; provisions for Part C—Prevention of Significant Deterioration (PSD) and Part D—New Source Review (NSR) permit programs; criteria for stationary source emission control measures, monitoring and reporting; provisions for modeling; and provisions for public and local agency participation. See the General Preamble for further explanation of these requirements (57 FR 13498, April 16, 1992). The EPA's approval of Idaho's SIP for attainment and maintenance of national standards can be found at 40 CFR 52.673. For purposes of redesignation of the Pinehurst PM10 NAA, the EPA has reviewed the IDEQ SIP and finds that the IDEQ has satisfied all applicable requirements under CAA section 110(a)(2) for the PM10 NAAQS.
2. Part D Requirements
Part D of the CAA contains general requirements applicable to all areas designated nonattainment. The general requirements are followed by a series of subparts specific to each pollutant. All PM10 nonattainment areas must meet the general provisions of Subpart 1 and the specific PM10 provisions in Subpart 4, “Additional Provisions for Particulate Matter Nonattainment Areas.” The following paragraphs discuss these requirements as they apply to the Pinehurst PM10 NAA.
2a. Part D, Section 172(c)(2)—Reasonable Further Progress
Section 172(c) contains general requirements for NAA plans. A thorough discussion of these requirements may be found in the General Preamble (57 FR 13538, April 16, 1992). CAA section 172(c)(2) requires nonattainment plans to provide for reasonable further progress (RFP). Section 171(1) of the CAA defines RFP as “such annual incremental reductions in emissions of the relevant air pollutant as are required by this part (part D of title I) or may reasonably be required by the Administrator for the purpose of ensuring attainment of the applicable national ambient air quality standard by the applicable date.” The requirements for reasonable further progress, identification of certain emissions increases and other measures needed for attainment were satisfied with the approved Pinehurst PM10 NAA SIP (59 FR 43745 and 60 FR 27891). In its August 23, 2001 action (66 FR 44304), the EPA determined that the Pinehurst NAA attained the 24-hour PM10 NAAQS by the December 31, 1994 and December 31, 2000, attainment dates. Therefore, the EPA believes no further showing of RFP or quantitative milestones is necessary.
2b. Part D, Section 172(c)(3)—Emissions Inventory
For redesignation, section 172(c)(3) of CAA requires a comprehensive, accurate, current inventory of actual emissions from all sources in the Pinehurst PM10 NAA. The IDEQ included an emissions inventory for the Pinehurst area for the year 2013 in the September 29, 2017 submittal. The IDEQ used 2013 as a base year for the emissions inventory, including data from the 2014 periodic emission inventory (PEI), as the IDEQ determined that it is representative of emissions during the five-year period associated with air quality data demonstrating attainment. The IDEQ has demonstrated that the 2013 base year emissions inventory is current, accurate, and comprehensive, and therefore meets the requirements of section 172(c)(3) of the CAA.
2c. Part D, Section 172(c)(5)—New Source Review (NSR)
The CAA requires all nonattainment areas to meet several requirements regarding NSR. The IDEQ must have an approved major NSR program that meets the requirements of CAA section 172(c)(5). The Part D NSR rules for PM10 nonattainment areas in Idaho were approved by the EPA on July 23, 1993 (58 FR 39445) and amended on January 16, 2003 (68 FR 2217). Revisions to Idaho's NSR rules were most recently approved by the EPA on November 26, 2010 (75 FR 72719). Within the boundaries of the Pinehurst PM10 NAA, the requirements of the Part D NSR program will be replaced by the IDEQ's Prevention of Significant Deterioration (PSD) program requirements upon the effective date of redesignation. The currently approved NSR provisions meet the requirements of 172(c)(5) and therefore this condition for proposed redesignation is satisfied.
2d. Part D, Section 172(c)(7)—Compliance With CAA Section 110(a)(2): Air Quality Monitoring Requirements
Once an area is redesignated, the IDEQ must continue to operate an appropriate air monitoring network in accordance with 40 CFR part 58 to verify the attainment status of the area. On January 15, 1980, the IDEQ submitted a comprehensive air quality monitoring plan, intended to meet the requirements of 40 CFR part 58. The EPA approved the plan on July 28, 1982 (40 CFR 52.760). This monitoring plan has been updated, with the most recent submittal in June 2017, with approval by the EPA on November 8, 2017. The monitoring plan describes the PM10 monitoring network throughout Idaho, including the Pinehurst monitoring site. The Pinehurst monitoring site is operated in compliance with the EPA monitoring guidelines set forth in 40 CFR part 58, Ambient Air Quality Surveillance. In addition, the Pinehurst PM10 NAA LMP submittal provides a commitment to continue operation of the PM10 monitoring network in accordance with 40 CFR part 58, and to annually verify continued attainment of the 24-hour PM10 NAAQS in Pinehurst through the Annual Ambient Air Monitoring Network Plan. Any changes to the monitoring site will be made via the Annual Ambient Air Monitoring Network Plan or formal communication. The currently approved monitoring plan and associated program meet the requirements of 172(c)(7) and therefore this condition for proposed redesignation is satisfied.
2e. Part D, Section 172(c)(9)—Contingency Measures
The CAA requires that contingency measures take effect if an area fails to meet RFP requirements or fails to attain the NAAQS by the applicable attainment date. On August 23, 2001, the EPA determined that the Pinehurst NAA attained the PM10 NAAQS by the applicable attainment dates of December 31, 1994 and December 31, 2000 (66 FR 44304). Therefore, attainment planning contingency measures are no longer required under section 172(c)(9) of the CAA. However, maintenance plan contingency provisions are required for maintenance plans under section 175(a)(d). Please see section IV.I. for a description of Idaho's maintenance plan contingency provisions.
2f. Part D, Section 189(a), (c) and (e)—Additional Provisions for Particulate Matter Nonattainment Areas
CAA sections 189(a), (c) and (e) apply to moderate PM10 nonattainment areas. Any of these requirements which were applicable and due prior to the submission of the redesignation request must be fully approved into the SIP before redesignating the area to attainment. With respect to the Pinehurst NAA, these requirements include:
(a) Provisions to assure that reasonably available control measures were implemented by December 31, 1994 and December 31, 2000 (section 189(a)(1)(C));
(b) Either a demonstration that the plan provided for attainment as expeditiously as practicable but not later than December 31, 1994 and December 31, 2000, or a demonstration that attainment by that date was impracticable (section 189(a)(1)(B));
(c) Quantitative milestones which were achieved every three years and which demonstrate RFP toward attainment by December 31, 1994 and December 31, 2000 (section 189(c)(1)); and
(d) Provisions to assure that the control requirements applicable to major stationary sources of PM10 also apply to major stationary sources of PM10 precursors except where the Administrator determined that such sources do not contribute significantly to PM10 levels which exceed the NAAQS in the area (section 189(e)).
Provisions for reasonably available control measures, attainment demonstration, and RFP milestones were conditionally approved into the Pinehurst PM10 SIP on August 25, 1994 (59 FR 43745) and on May 26, 1995 (60 FR 27891). The EPA's approval of the July 13, 1995 contingency plan on October 2, 2014 (79 FR 59435) fully approved these required elements The EPA approved changes to Idaho's major NSR rules on July 17, 2012 (77 FR 41916) and November 26, 2010 (75 FR 72719). The IDEQ's major nonattainment NSR rules and PSD rules include control requirements that apply to major stationary sources of PM10 and PM10 precursors in nonattainment and attainment/unclassifiable areas. Therefore, the EPA proposes that the requirements of 189(a)(c) and (e) for this proposed redesignation is satisfied.
D. Has the IDEQ demonstrated that the air quality improvement is due to permanent and enforceable reductions?
Section 107(d)(3)(E)(iii) of the CAA provides that a NAA may not be redesignated unless the EPA determines that the improvement in air quality is due to permanent and enforceable reductions in emissions resulting from implementation of the SIP. Permanent and enforceable control measures in the Pinehurst PM10 SIP include controls primarily focused on residential wood combustion. The Pinehurst PM10 NAA LMP submittal describes its woodstove changeout program which resulted in 76 stove replacements by 1994 and an additional 87 replacements between 1996 and 2015. According to a recent survey in the community these 163 changeouts account for 60% of the uncertified devices in the area. Between 2015-17, 40 additional woodstoves have been changed out to cleaner burning devices under this program; 31 to EPA certified, 1 to propane, and 8 to natural gas. Additional permanent controls in the area include the weatherization of 30 homes in the mid-1990s which provided for reductions in emissions by reducing home heating requirements which in turn reduce the need for additional fuel and the associated emissions.
E. Does the area have a fully approved maintenance plan pursuant to section 175A of the act?
In this action, we are proposing to approve the LMP in accordance with the principles outlined in the LMP Option Memo. Upon final approval, the Pinehurst NAA will have a fully approved maintenance plan.
F. Has the IDEQ demonstrated that the Pinehurst NAA qualifies for the LMP Option?
The LMP Option Memo outlines the requirements for an area to qualify for a LMP. First, the area should be attaining the NAAQS. On August 23, 2001, the EPA determined that the Pinehurst NAA attained the PM10 NAAQS by December 31, 1994 and December 31, 2000 (66 FR 44304). The EPA has reviewed recent ambient air quality data for the 24-hour PM10 NAAQS, and has determined that the Pinehurst NAA continues to attain the 24-hour PM10 NAAQS. Please see section IV.A. above for a detailed discussion.
Second, the average design value (ADV) for the past five years of monitoring data must be at or below the critical design value (CDV). The CDV is a margin of safety value at which an area has been determined to have a one in ten probability of exceeding the NAAQS. The LMP Option Memo provides two methods to review monitoring data for the purpose of determining qualification for an LMP. The first method is a comparison of a site's ADV with the CDV of 98 µg/m for the 24-hour PM10 NAAQS. A second method that applies to the 24-hour PM10 NAAQS is the calculation of a site-specific CDV and a comparison of the site-specific CDV with the ADV for the past five years of monitoring data. The IDEQ's LMP submittal provides a comparison of five-year ADVs compared to the 24-hour and annual CDVs, as described in the first method for review of monitoring data to determine qualification for a LMP. The IDEQ's analysis demonstrates that the Pinehurst NAA has met the LMP design value criteria using the tabular look up method which showed the area to be meeting the CDV with a five-year design value of 83 µg/m. The EPA has reviewed the calculations and concurs with the IDEQ's findings that the area has a five-year design value of 83 µg/m for both 2011-2015 and the most recently available five year DV of 2012-2016. Therefore, the EPA finds that the Pinehurst NAA meets the design value criteria outlined in the LMP Option Memo.
See “Limited Maintenance Plan Option for Moderate PM10 Nonattainment Areas” memo from Director Lydia Wegman to Regional Offices dated August 9, 2001.
See “Limited Maintenance Plan Option for Moderate PM10 Nonattainment Areas” memo from Director Lydia Wegman to Regional Offices dated August 9, 2001.
See “Limited Maintenance Plan Option for Moderate PM10 Nonattainment Areas” memo from Director Lydia Wegman to Regional Offices dated August 9, 2001.
This LMP design value is dependent upon data being excluded from a high wind exceptional event also proposed for approval in this notice.
Third, the area must meet the motor vehicle regional emissions analysis test described in attachment B of the LMP Option Memo. Using the methodology outlined in the LMP Option Memo, the IDEQ has submitted an analysis of whether increased emissions from on-road mobile sources would increase PM10 concentrations in the Pinehurst NAA to levels that would threaten the assumption of maintenance that underlies the LMP policy. Using this methodology, the IDEQ has determined that the Pinehurst NAA passes the motor vehicle regional emissions analysis test. The motor vehicle regional emissions analysis test results of 83.19 µg/m3 and 83.36 µg/m3 when adjusted for growth are below the 98 µg/m3 annual standard and meet the margin of safety requirements. The EPA has reviewed the calculations in the IDEQ's Pinehurst NAA LMP submittal in Section 3.1 and concurs with this conclusion.
The LMP Option Memo requires all controls relied on to demonstrate attainment remain in place for a NAA to qualify for a LMP. The LMP developed by IDEQ will continue to implement the control measures relied upon to demonstrate attainment. Therefore, EPA proposes to find that the Pinehurst PM10 NAA meets the qualification criteria set forth in the LMP Option Memo, and therefore qualifies for a LMP.
The LMP Option Memo also indicates that once a state submits a LMP and it is in effect, the IDEQ will be expected to determine, on an annual basis, that the LMP criteria are still being met. If the IDEQ determines that the LMP criteria are not being met, it should take action to reduce PM10 concentrations enough to requalify for the LMP. One possible approach the IDEQ could take is to implement contingency measures. Section IV.I. provides a description of contingency provisions submitted as part of the Pinehurst NAA LMP submittal. The EPA believes the contingency provisions submitted by the IDEQ meet the requirements of CAA section 175A as outlined in the LMP Option memo.
G. Does the IDEQ have an approved attainment emissions inventory which can be used to demonstrate attainment of the NAAQS?
Pursuant to the LMP Option Memo, the IDEQ's approved attainment plan should include an emissions inventory which can be used to demonstrate attainment of the NAAQS. The inventory should represent emissions during the same five-year period associated with air quality data used to determine whether the area meets the applicability requirements of the LMP Option. The IDEQ should review its inventory every three years to ensure emissions growth is incorporated in the inventory if necessary.
The IDEQ's Pinehurst PM10 NAA LMP submittal includes an emissions inventory, with a base year of 2013. After reviewing the 2013 emissions inventory and determining that it is current, accurate and complete, as well as reviewing monitoring data, the EPA has determined that the 2013 emissions inventory is representative of the attainment year inventory because the NAAQS was not violated during 2013. In addition, the year 2013 is representative of the level of emissions during the time period used to calculate the average design value because 2013 is one of the years during the five-year period used to calculate the design value. The submittal meets EPA guidance, as described above, for purposes of an attainment emissions inventory.
H. Does the LMP include an assurance of continued operation of an appropriate EPA-approved air quality monitoring network, in accordance with 40 CFR part 58?
A PM10 monitoring network was established in the Pinehurst area in 1985. The monitoring network was developed and has been maintained in accordance with Federal siting and design criteria in 40 CFR part 58, and in consultation with EPA Region 10. The EPA most recently approved the IDEQ's air monitoring plan on November 8, 2017. In the Pinehurst PM10 NAA LMP submittal, the IDEQ commits to continue to operate its monitoring network to meet the EPA requirements at 40 CFR part 58 and identify any issues or adjustments via the Annual Ambient Air Monitoring Network Plan or formal communication. The submittal contains an assurance of continued operation of the PM10 monitoring network. The submittal meets EPA LMP submission requirements with respect to maintenance of a monitoring network.
I. Does the plan meet the clean air act requirements for contingency provisions?
The CAA section 175A states that a maintenance plan must include contingency provisions, as necessary, to ensure prompt correction of any violation of the NAAQS which may occur after redesignation of the area to attainment. As explained in the LMP Option Memo and the Calcagni Memo, these contingency provisions are considered to be an enforceable part of the federally-approved SIP. The maintenance plan should clearly identify the provisions to be adopted, a schedule and procedures for adoption and implementation, and a specific time limit for action by the IDEQ. The maintenance plan should identify the events that would “trigger” the adoption and implementation of a contingency provision, the contingency provision that would be adopted and implemented, and the schedule indicating the time frame by which the IDEQ would adopt and implement the provision. The LMP Option Memo and Calcagni Memo state that the EPA will determine the adequacy of a contingency plan on a case-by-case basis. At a minimum, it must require that the IDEQ will implement all measures contained in the CAA part D nonattainment plan for the area prior to redesignation.
In the Pinehurst PM10 NAA LMP submittal, the IDEQ has included maintenance plan contingency provisions to ensure the area continues to meet the PM10 NAAQS. The submitted LMP includes the Annual Network Plan review process as the triggering mechanism for identifying if the Pinehurst area violates the PM10 NAAQS. If triggered the LMP identifies a list of specific control measures as listed in section 3.5.2 of their submittal to reduce emissions, including potential measures that would control emissions associated with residential wood combustion, controlling road-dust related emissions, and refuse burning for evaluation and a process for selection. Therefore, the EPA believes the contingency provisions submitted in the Pinehurst PM10 NAA LMP are adequate to meet CAA section 175A requirements.
J. How is conformity treated under a limited maintenance plan?
See “Limited Maintenance Plan Option for Moderate PM10 Nonattainment Areas” memo from Director Lydia Wegman to Regional Offices dated August 9, 2001.
The transportation conformity rule (40 CFR 51. 390 and 40 CFR 93.100-129) and the general conformity rule (40 CFR 93.150-165) apply to nonattainment areas and maintenance areas operating under maintenance plans. Under either conformity rule one means of demonstrating conformity of Federal actions is to indicate that expected emissions from planned actions are consistent with the emissions budget for the area. Emissions budgets in LMP areas may be treated as essentially not constraining for the length of the maintenance period because it is unreasonable to expect that an area satisfying the LMP criteria will experience so much growth during that period of time such that a violation of the PM10 NAAQS would result. While this policy does not exempt an area from the need to affirm conformity, it does allow the area to demonstrate conformity without undertaking certain requirements of these rules. For transportation conformity purposes, EPA would be concluding that emissions in these areas need not be capped for the maintenance period, and, therefore, a regional emissions analysis would not be required. Similarly, Federal actions subject to the general conformity rule could be considered to satisfy the “budget test” specified in § 93.158(a)(5)(i)(A) of the rule, for the same reasons that the budgets are essentially considered to be unlimited.
The Pinehurst area is an isolated rural area . Transportation conformity determinations in isolated rural nonattainment and maintenance areas are required only when a new non-exempt Federal Highway Administration (FHWA)/State Transportation Agency (STA) project needs funding or approval. Thus, in the event that a conformity analysis is required, the state agency responsible for conducting transportation conformity must document and ensure that:
As defined in 40 CFR 93.101, Isolated rural nonattainment and maintenance areas are areas that do not contain or are not part of any metropolitan planning area as designated under the transportation planning regulations. Isolated rural areas do not have Federally required metropolitan transportation plans (MTPs) or transportation improvement programs (TIPs) and do not have projects that are part of the emissions analysis of any metropolitan planning organization's (MPO's) MTP or TIP. Projects in such areas are instead included in statewide transportation improvement programs.
(a) The interagency consultation procedures meet the applicable requirements of 40 CFR 93.105(c)(1)(vi);
(b) Conformity is determined as specified in 40 CFR 93.109(g) for isolated rural areas.
The minimum criteria by which the EPA determines whether a SIP is adequate for conformity purposes are specified at 40 CFR 93.118(e)(4). The EPA's analysis of how the LMP satisfies these criteria for transportation conformity is found in the docket. The EPA proposes to find adequate Idaho's LMP for Pinehurst for transportation conformity purposes.
Upon final approval of the Pinehurst PM10 NAA LMP, the Pinehurst area will be exempt from performing a regional emissions analysis, but must meet project-level conformity analysis as well as the transportation conformity criteria located in 40 CFR 93.109(g) for isolated rural areas.
V. 2013 PM10 High Wind Exceptional Event
The CAA allows for the exclusion of air quality monitoring data from design value calculations when there are exceedances caused by events, such as wildfires or high wind events, that meet the criteria for an exceptional event identified in the EPA's implementing regulations, the Exceptional Events Rule at 40 CFR 50.1, 50.14 and 51.930. In 2013 emissions from a high wind event entrained dust and impacted PM10 concentrations recorded at the Pinehurst monitor. For purposes of this Pinehurst PM10 redesignation and LMP, the IDEQ submitted an exceptional event demonstration to request exclusion of the data. The EPA evaluated the IDEQ's exceptional event demonstration for the flagged values of the 24-hour PM10 NAAQS for September 15, 2013, at the monitor in Pinehurst, Idaho, with respect to the requirements of the EPA's Exceptional Events Rule (40 CFR 50.14) and determined that IDEQ met the rule requirements. On March 2, 2017, the EPA concurred with the IDEQ's request to exclude event-influenced data for September 15, 2013. As such, the event-influenced data have been removed from the data set used for regulatory purposes and, for this proposed action, the EPA relies on the calculated values that exclude the event-influenced data. The EPA now proposes approval of the IDEQ's request to exclude data from September 15, 2013, in determining PM10 attainment as a high wind exceptional event. For further information, refer to the IDEQ's Exceptional Event demonstration package and the EPA's concurrence and analysis located in the docket for this regulatory action.
VI. West Silver Valley 2012 Annual PM2. 5 Emission Inventory
A. Requirements for Emissions Inventories
Section 172(c)(3) of the CAA requires a state with an area designated as nonattainment to submit a “comprehensive, accurate, current inventory of actual emissions from all sources of the relevant pollutant” for the NAA. By requiring an accounting of actual emissions from all sources of the relevant pollutants in the area, this section provides for the base year inventory to include all emissions from sources in the NAA that contribute to the formation of a particular NAAQS pollutant. For the 2012 annual PM2.5 NAAQS, this includes direct PM2.5 (condensable and filterable) as well as the precursors to the formation of secondary PM2.5: Nitrogen oxides (NOX), sulfur dioxide (SO2), volatile organic compounds (VOCs), and ammonia (NH3) (40 CFR 51.1008; 81 FR 58028). Inclusion of PM2.5 and all of the PM2.5 precursors in the emissions inventory is necessary in order to inform other aspects of the attainment plan development process, if such a plan is required. The SIP submission should include documentation explaining how the state calculated the emissions data for the base year inventory. The specific PM2.5 emissions inventory requirements are set forth in 40 CFR 51.1008. The EPA has provided additional guidance for developing PM2.5 emissions inventories in Emissions Inventory Guidance for Implementation of Ozone and Particulate Matter National Ambient Air Quality Standards (NAAQS) and Regional Haze.
B. West Silver Valley PM 2.5 Base Year Emissions Inventory
The IDEQ developed a 2013 base year emissions inventory for the WSV annual PM2.5 NAA. The base year emissions inventory includes data from 2013 and 2014 and in large part was extracted from the 2014 periodic emissions inventory (PEI) which is used to populate the EPA's National Emissions Inventory (NEI). The 2013 base year inventory is one of the three years used to designate the area as nonattainment. This base year inventory presents direct PM2.5 emissions (condensable and filterable) and emissions of all PM2.5 precursors (NOX, VOCs, NH3, and SO2) to meet the emissions inventory requirements of CAA section 172(c). The IDEQ provided inventories from all sources in the WSV NAA, including nonpoint/area sources, point sources, nonroad sources, and onroad sources. The inventory is based on annual emissions in tons per year. The top source sectors of direct PM2.5 in the WSV are prescribed burns (88.91 tons/year (tpy)), residential wood combustion (52.61 tpy), onroad (17.25 tpy), unpaved roads (13.61 tpy), and nonroad (7.24 tpy) emissions.
The largest source category of direct PM2.5 emissions in the WSV was from prescribed burning, accounting for 44.9% of direct PM2.5. These emissions came from primarily large and small scale permitted burners who burn forest waste mostly during the fall season. Emissions were estimated by extracting data, including fuel loading-moisture-acres burned-emissions factors, from prescribed burn databases maintained by the Idaho-Montana Air Shed Group and Idaho Department of Lands, and the Forest Practices Act Compliance database. The second largest source category is residential wood combustion (RWC). The emissions come from various residential devices designed to heat homes through burning wood whether in solid or pellet form. Emissions from RWC, on an annual basis, account for about 26.6% of the base year direct PM2.5 emissions. These emissions were estimated using the EPA's Microsoft Access RWC tool v2.1 and estimates were adjusted with information from a local woodstove survey along with information from the ongoing woodstove changeout program in the area. The next three largest source categories, onroad emissions, unpaved roads emission, and nonroad emissions accounted for 30.9% of the direct PM2.5 in the base year emissions inventory. The onroad emissions source category includes emissions from motor vehicles and road dust from paved roads. The nonroad emissions source category includes winter and summer recreation vehicles and emissions generated from logging, construction and mining, and other minor nonroad sources. Onroad and nonroad emissions were calculated using MOVES2014.
C. EPA's Evaluation
The EPA has reviewed the results, procedures, and methodologies for the WSV Annual PM2.5 NAA base year emissions inventory. The EPA has determined that the 2013 base year inventory for the WSV is based on the most current and accurate information available to the IDEQ at the time the inventories were being developed. The inventories comprehensively address all source categories in the WSV NAA, actual emissions are provided, and appropriate procedures were used to develop the inventories. We are proposing to approve the 2013 base year emissions inventory for the WSV NAA as meeting the requirements of CAA section 172(c)(3) and 40 CFR 51.1008(a)(1).
VII. Proposed Action
The EPA is proposing to approve the Pinehurst PM10 NAA LMP submitted by the IDEQ for the Pinehurst NAA and concurrently redesignate the area to attainment for the PM10 NAAQS. The EPA has reviewed air quality data for the area and determined that the Pinehurst NAA attained the PM10 NAAQS by the required attainment date, and that air monitoring data continue to show attainment. The EPA is proposing to approve that the Pinehurst PM10 NAA LMP meets all of the requirements of an LMP and that the Pinehurst NAA meets all of the requirements of redesignation as described in this action.
The EPA is also taking action to propose approval of the September 15, 2013, high wind exceptional event that impacted PM10 values in the area.
The EPA is also taking action to propose approval of the WSV Annual PM2.5 base year Emissions Inventory as meeting CAA 172(c)(3) requirements.
VIII. Statutory and Executive Order Reviews
Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the CAA 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 CAA. Accordingly, this proposed action merely approves state law as meeting Federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this proposed 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 it 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 in 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 governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).
List of Subjects
40 CFR Part 52
- Environmental protection
- Air pollution control
- Incorporation by reference
- Intergovernmental relations
- Particulate matter
- Reporting and recordkeeping requirements
40 CFR Part 81
- Environmental protection
- Air pollution control
- National parks
- Wilderness areas
Authority: 42 U.S.C. 7401 et seq.
Dated: April 30, 2018.
Chris Hladick,
Regional Administrator, Region 10.
[FR Doc. 2018-09992 Filed 5-10-18; 8:45 am]
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