Environmental Quality, Air Quality

Rule R307-110

General Requirements: State Implementation Plan

Five-Year Notice of Review and Statement of Continuation

DAR File No.: 35774
Filed: 02/01/2012 04:25:34 PM

NOTICE OF REVIEW AND STATEMENT OF CONTINUATION

Concise explanation of the particular statutory provisions under which the rule is enacted and how these provisions authorize or require the rule:

Rule R307-110 incorporates by reference the state implementation plan (SIP) allowed under Subsection 19-2-104(3)(e), which allows the Air Quality Board to prepare a state plan for the prevention, abatement, and control of air pollution. Clean Air Act Section 110(a)(1) (42 USC 7410(a)(1)) requires that each state adopt and submit to the Environmental Protection Agency (EPA) a plan providing for implementation, maintenance, and enforcement of each health standard promulgated by EPA. If a state fails to do so, EPA is to issue a federal implementation plan in its place, and other federal sanctions also would apply.

Summary of written comments received during and since the last five-year review of the rule from interested persons supporting or opposing the rule:

Rule R307-110 has been amended four times since its last five-year review. FIRST AMENDMENT: DAR No. 29514, effective 05/02/2007 -- No comments were received on this amendment.

SECOND AMENDMENT: DAR No. 31557, effective 11/10/2008 -- The following 15 comments were received on this amendment: COMMENT 1 (Kathy Van Dame, Wasatch Clean Air Coalition): SIP XX.E.3.a(1)(a)(i) and (ii) apparently refer to Subsections R307-250-4(1)(a) and (b). In XX the different types of sources are named "Category 1" and "Category 2". In Section R307-250-4, there is no such simple descriptor. In XX, Category 2 sources are described as "WEB sources that commenced operation on 01/01/2008 or a later date" while in Subsection R307-250-4(1)(b) they are described as "A new source that begins operation after the program trigger date." If in fact, the two descriptions refer to each other, they should be harmonized. In any case, the reference within XX.E.3.a(1)(a) to Rule R307-250 should be to a specific part of Rule R307-250. STAFF RESPONSE: The two descriptions referred to in the comment are not intended to mean the same thing and do not need to be harmonized. The applicability language in the rule identifies the sources that are subject to the trading program. Applicability is determined based on actual emissions for existing sources and Potential to Emit (PTE) for new sources. The language in the state implementation plan (SIP) further divides the sources that are subject to the program into Category 1 and Category 2 sources. Category 1 sources will receive their floor allocation from either the utility or non-utility pool of allowances. These sources will also be eligible for a reducible allocation. Category 2 sources will receive their floor allowances from the new source set-aside, and will not be eligible for a reducible allocation. The reference within SIP Section XX.E.3.a(1)(a) has been changed as recommended to refer to Section R307-250-2 where the term "WEB source" is defined. COMMENT 2 (Kathy Van Dame, Wasatch Clean Air Coalition): In SIP XX.E.3.a(1)(c)(i) "early reduction credit," XX E.3. "early reduction allocation," and the title of Subsection R307-250-7(5) "Early Reduction Bonus Allocation," these terms apparently all refer to the same item, if so, they should be harmonized. In the case of multiple, interlocking documents, lack of uniformity of terms contributes to misunderstandings and disputes. STAFF RESPONSE: The SIP and rule text were modified as recommended to use a consistent terminology "early reduction bonus allocation." COMMENT 3 (EPA Region 8): There are a number of places where the Utah SIP differs from the 04/23/2008 Model SIP/TIP on WRAP's website. For example, Table 8 has different milestone values for the years 2003-2009, Table 10 has different numbers for the 2018 non-utility portion, and Section E.3(a)(2)(g)(ii) has 2000-2006 as the baseline period while the Model SIP/TIP has 2006 as the baseline. We recommend that Utah modify the 2008 SIP to match the 04/23/2008 Model SIP/TIP on WRAP's website. STAFF RESPONSE: In earlier versions of the model SIP that was developed by the four participating states the tribal set-aside was inadvertently left out of the milestone calculation. When this error was discovered, it was corrected in the model SIP but not in Utah's draft SIP. The milestone numbers in Table 8 have been corrected to match the milestones that were developed through the regional process and are included in the model SIP. COMMENT 4 (EPA Region 8): In the flow control example in provision E.(3)(h)(2) on page 60 of the 2008 SIP, the 2008 SIP refers to the 2010 milestone as "(5-state, no smelter)" which is not correct. We recommend that the parenthetical phrase be deleted. The corresponding reference in the Model SIP is provision C4.2(b)(3). STAFF RESPONSE: The example was changed as recommended. COMMENT 5 (EPA Region 8): Utah's RH SIP does not adequately address Utah's impacts from NOx and PM on Class I areas, both in and out of state. 40 CFR Section 51.309(d)(4)(vii) requires that SIPs contain necessary long term strategies and best available retrofit technology (BART) requirements for stationary source emissions of NOx and PM. Utah's NOx emissions have a significant impact on several in-State and out-of-State Class I areas. Specific examples include Capital Reef National Park in Utah and Craters of the Moon National Monument and Preserve in Idaho. In order to address impacts from NOx and PM, 40 CFR Section 51.309(a) requires that each 309 State follow 51.308 requirements, both for BART and reasonable progress, in evaluating Class I areas outside of the Colorado Plateau affected by the State. 40 CFR Section 51.308(d)(3) requires that States must submit a long term strategy that addresses regional haze visibility impairment for each Class I area located outside the State which may be affected by emissions from the State. 40 CFR Section 51.308(d)(3) also requires that long-term strategies include enforceable emission limitations (see comments in 2. above), compliance schedules, and other measures necessary to achieve reasonable progress goals. STAFF RESPONSE: Utah's SIP contains the "necessary long-term strategies and BART requirements for stationary source PM and NOx emissions" as required by Section 309(d)(4)(vii) in several parts of the SIP. Section XX.D.6 includes a BART assessment for NOx and PM, and Table 6 shows the emission reductions that will be achieved by the retrofitted units that are subject to BART: NOx emissions are reduced by 6,206 tons/yr and PM10 emissions are reduced by 926 tons/yr. Section XX.D.5 contains an assessment of NOx and PM strategies that was prepared for the 2003 SIP. This analysis concluded that for the vast majority of Class I areas throughout the WRAP region NOx and PM emissions are not a major contributor to visibility impairment on the average 20% best and 20% worst days. However, on some of the worst days nitrates and PM are the main components of visibility impairment. This assessment was consistent with the conclusions of the GCVTC that recommended focusing efforts on stationary source SO2 emissions because of the widespread impact on visibility impairment. Finally, Section XX.K.1 of the SIP outlines the significant overall emission reductions in NOx and PM in Utah and the region. NOx emissions decline 36% between 1996 and 2018 and PM2.5 emissions decline 38% and SO2 emissions decline 33% during this same time period. Coarse matter emissions are projected to increase, although there is much greater uncertainty in the emission inventories for windblown dust. Taken as a whole Utah's SIP shows the necessary long-term strategies for PM and NOx emissions. Class I areas on the Colorado Plateau (including Capital Reef National Park), as well as all other Class I areas that are affected by emissions from Utah will benefit from these significant emissions reductions. Utah has participated in the technical and policy forums of the Western Regional Air Partnership (WRAP) as described in Section XX.M of the plan, and further detailed in Appendix D of the plan. Through that process Utah has shared emissions data and other technical information with other states that have Class I areas that might be impacted by emissions from Utah. As described above, Section XX.K.1 of the SIP outlines the overall significant emission reductions in Utah, and these reductions will benefit all Class I areas that might be impacted by emissions from Utah. Utah's emissions reductions are included in the overall WRAP modeling analysis and will therefore be reflected in the reasonable progress demonstrations that are prepared by neighboring states. The following paragraph has been added to the end of Section XX.K.1 to clarify that the emission reductions are occurring throughout the state and will benefit all Class I areas that are impacted by emissions from Utah. The emission reductions in Utah occur throughout the state and will therefore benefit all Class I areas outside of Utah that might be impacted by emissions from Utah: Northern Utah -- The urban area in northern Utah that may impact Class I areas in Idaho, Nevada and Wyoming will have a significant reduction in NOx emissions from mobile sources as described in Section XX.F of this plan. Mobile (on-road and non-road) NOx emissions in the four main urban counties (Weber, Davis, Salt Lake, and Utah) are projected to decrease by 42,000 tons/yr or 61% between 2002 and 2018. Mobile sources dominate the NOx emission inventory in Utah's urban area. Class I areas that have some days when nitrates are a significant contributor to visibility impairment, such as Craters of the Moon National Park, will benefit from the NOx emission reductions during those episodes. Central and Southern Utah -- As described in Section XX.D.6 of this plan, two BART-eligible plants in central Utah are projected to decrease SO2 emissions by 13,200 tons and NOx emissions by 6,200 tons between 2002 and 2018. Central and Southern Utah are sparsely populated and the inventory is dominated by point sources. The exception is Washington County that is becoming more urban due to the growth of St. George and the inventory is therefore dominated by mobile source emissions. In Washington County, NOx emissions from mobile sources (on-road and non-road) are projected to decrease by 2,300 tons or 57% between 2002 and 2018. These emission reductions will benefit Class I areas in southern Colorado, New Mexico and Arizona that may be affected by emissions from Utah. Eastern Utah -- Oil and Gas emissions dominate the inventory in eastern Utah and are increasing between 2002 and 2018. Approximately 90% of current emissions from oil and gas occur on land that is under the jurisdiction of the Ute Indian Tribe of the Uintah Ouray Reservation and is therefore not covered by Utah's SIP. The inventory compiled by the WRAP does not currently separate out these emissions that are not under Utah's jurisdiction. These emissions may affect Class I areas in Northeastern Colorado and the State of Utah expects that this impact will be addressed in the TIP or FIP that is developed for the Ute Tribe. COMMENT 6 (National Parks Service): Section 51.309(d)(4)(vii) required that the SIP contain provisions for a long-term strategy for stationary source emissions of NOx and PM. The Utah SIP provides some assessment of BART for NOx and PM but does not address whether additional emissions controls, beyond those considered for BART, are appropriate to provide for reasonable progress. Given the importance of nitrate at a substantial number of worst days at Utah's Class I areas, we believe that an examination of stationary source controls for nitrogen oxides is required in a regional haze SIP. STAFF RESPONSE: See response to Comment 5. COMMENT 7 (National Parks Service): According to WRAP's Technical Support System (TSS), the 20% worst days at Capitol Reef National Park are calculated based on 106 monitored days between 2000 and 2004. Of those, 23 days are dominated by nitrate and an additional 4 days have nitrate doing a close second to sulfate as the key pollutant contributing to haze. The TSS includes modeling for 2002, when 44 of the worse days are dominated by nitrate. That year Utah's sources are the major contributor on one day. While the SIP does not need to establish reasonable progress goals for Capitol Reef or the other Utah Class I Parks at this time, some decision and supporting assessments on additional NOx controls must be included in this SIP. STAFF RESPONSE: See response to Comment 5. COMMENT 8 (National Parks Service): One critical omission from the SIP is a discussion of how the programs contained in the SIP meet Utah's obligation to address the effects of its emissions on visibility in Class I areas outside of Utah. STAFF RESPONSE: See response to Comment 5. COMMENT 9 (National Parks Service): The regional haze rule requires the SIP to examine how Utah's SIP addresses the State's contribution to reasonable progress at Craters of the Moon National Monument (CRMO). Utah could examine how emissions changes expected from implementation of its SIP would reduce Utah's impact on CRMO between the baseline period and 2018. If Utah reduces its contribution by the same or greater percent required to meet the uniform rate of progress target established by EPA, then the State would be clearly demonstrating that it is doing its fair share toward reasonable progress at CRMO. Otherwise, if the reduction is significantly less than the percent needed to achieve the uniform rate of progress, Utah should establish a list of stationary sources and a geographical area for mobile sources that are most influencing CRMO. The State should also assess, using the four reasonable progress factors, what an appropriate long term strategy should be. STAFF RESPONSE: See response to Comment 5. COMMENT 10 (National Parks Service): Utah has provided specifics on the components listed in 40 CFR 50.309 for Class I areas on the Colorado Plateau. The specifics on programs related to sulfur dioxide backstop trading program, mobile sources, fire programs, road dust, and renewable energy highlight Utah's commitment to assuring reasonable progress. The SIP language is exemplary in the way it balances fire program permitting with appropriate assessment of air quality concerns. STAFF RESPONSE: Thank you. COMMENT 11 (EPA Region 8): Utah's RH SIP does not contain a five factor BART analysis for NOx and PM, as required by 40 CFR Section 51.309(d)(4)(vii). States doing a 309 RH SIP must still do a BART analysis according to 40 CFR Section 51.308(e). Under 40 CFR Section 51.308(e)(1)(ii)(A), states "must take into consideration the technology available, the costs of compliance, the energy and non-air quality environmental impacts of compliance, any pollution control equipment in use at the source, and the remaining useful life of the source." The CAA also requires States to consider the five factors in making their BART determinations (see Clean Air Act Section 169A(g)(2)). STAFF RESPONSE: The latest revision of Section 51.309 Regional Haze "Requirements related to the Grand Canyon Visibility Transport Commission" has new provisions for stationary source emissions of NOx and PM. (71 Federal Register 60632, 10/13/2006). The rule requires Regional Haze SIPs to contain any necessary long term strategies and BART requirements for stationary source PM and NOx emissions (40 CFR Section51.309(d)(4)(vii). BART provisions may be submitted pursuant to either 51.308(e)(1) or 51.308(e)(2). 308(e)(1) requires a source by source five factor determination of BART for sources subject to BART in the State. 308(e)(2) allows a State to participate in an emissions trading program or other alternative measure instead of a source by source BART analysis. Utah, for NOx and PM emissions, has opted to use the 308(e)(1) source by source BART approach and an alternative backstop trading program for SO2 emissions. 308(e)(1)(ii)(A) requires a five factor analysis to determine the best system of continuous emission control technology available and associated emission reductions achievable for each subject to BART source. However, 308(e)(1)(ii)(B) requires that EGUs, with generating capacity greater than 750 MW, to make BART determinations pursuant to guidelines in Appendix Y to Part 51. In 40 CFR Part 51 "Regional Haze Regulations and Guidelines for BART Determinations; Final Rule" (07/06/2005) and in Appendix Y Part 51, EPA requires that coal-fired EGU's meet presumptive limits for NOx and SO2. EPA gives the option to States to challenge presumptive limits based on consideration of the five statutory factors. In effect EPA has determined that presumptive limits for NOx and SO2, are equivalent to a five factor BART analysis. "States, as a general matter, must require owners and operators of greater than 750 MW power plants to meet these BART emission limits... a State may establish different requirements if the State can demonstrate that an alternative determination is justified based on a consideration of the five statutory factors." (40 CFR Part 51 Guidelines for BART Determinations under the Regional Haze Rule (70 Federal Register 39135)). "For Coal-fired EGUs greater than 200 MW located at greater than 750 MW power plants and operating without post-combustion controls (i.e., SCR or SNCR), we have provided presumptive NOx limits, differentiated by boiler design and type of coal burned. You may determine that an alternative control level is appropriate based on careful consideration of the statutory factors." (Appendix Y Part 51 - IV (E)(5) FR 07/06/2005 39171). EPA determined presumptive limits for SO2 and NOx, for EGU sources greater than 750 MW, based on a five factor methodology as required in 50 CFR 51 Appendix Y of the BART Rule. The EPA determination of presumptive limits included: 1) identification of all potential BART-eligible EGUs; 2) presumption that BART eligible units were also Subject to BART; 3) technical analyses and industry research to determine applicable and appropriate SO2 and NOx control options; 4) economic analysis to determine cost effectiveness for each potentially BART-eligible EGU, and evaluation of historical emissions and forecast emission reductions for each BART-eligible EGU; and 5) NOx and SO2 CALPUFF modeling of emission impacts at model Class I areas. The analysis included 419 potential BART EGUs including the Hunter units 1 and 2 and Huntington units 1 and 2. The technical analysis conducted by EPA to determine presumptive BART limits for SO2 and NOx is equivalent to five factors BART determination of the 419 EGUs reviewed including the Hunter and Huntington Units. Under Appendix Y States are given the discretion to challenge presumptive limits through a five factor analysis but presumptive limits were developed by EPA as a reasonable, equivalent and mandatory substitution for a five factor analysis. COMMENT 12 (EPA Region 8): The CAA also requires States to consider the five factors in making their BART determinations (see Clean Air Act Section 169A(g)(2)). STAFF RESPONSE: EPA codified the CAA requirements under 169A(g)(2) in 40 CFR 51.308(e)(1)(ii) in the 07/06/2005 Final Rule "Regional Haze Regulations and Guidelines for Best Available Retrofit Technology (BART) Determinations: Final Rule." "Section 169(g)(2) of the CAA requires that States must consider the following factors in making BART determinations: 1) cost of compliance; 2) the energy and non-air quality environmental impacts of compliance; 3) any existing pollution control technology in use at the source; 4) the remaining life of the source; and 5) the degree of improvement in visibility which may reasonably be anticipated to result from the use of such technology. These statutory factors for BART were codified at 40 CFR 51.308(e)(1)(ii)" (Federal Register 70 39105). As outlined above (question No. 11) CFR 51.308(e)(1)(ii)(B) requires determination of BART for coal-fired EGU's with generating capacity above 750 MW, to be made pursuant to Appendix Y Part 51. Section IV (E)(5) of Appendix Y Part 51 clearly requires the implementation of presumptive NOx limits for coal-fired EGUs greater than 200 MW located at greater than 750 MW power plants. Under Appendix Y States are given the discretion to challenge presumptive limits through a five factor analysis but presumptive limits were developed by EPA as a reasonable, equivalent and mandatory substitution for a five factor analysis. It is DAQ's position that EPA has codified BART requirements under CAA Section 169A(g)(2) in the 07/06/2005 Final BART Rule and it is not within the purview of DAQ, or Region 8, to re-codify CAA statutes. COMMENT 13 (EPA Region 8): The State's RH SIP does not contain the elements necessary to make BART limits practically enforceable. Utah's SIP contains controls, emission limits and general schedules but does not include permit conditions specifying averaging times, record-keeping, monitoring, and specific schedules for compliance. The CAA requires that SIPs, including the RH SIP, contain elements sufficient to ensure emission limits are practically enforceable. It is not sufficient to include these elements in a separate permit or agreement that is not made part of the SIP. EPA does not consider permit conditions adequate to meet this enforceability requirement, as permit conditions may be modified. We also note that the BART guidelines require a 30-day averaging period for BART limits (see 70 FR 39172, col. 3, 07/06/2005). We view a 30-day or shorter averaging period as being necessary to protect visibility in the nearby Class I areas, since visibility is sensitive to short term spikes in pollutants which contribute to visibility impairment. STAFF RESPONSE: The Utah Regional Haze SIP includes all elements required under CAA Section 110 and specifically Section 110 (a)(2) including: 1) emission reduction control technology; 2) emission limits; 3) construction schedules; 4) record-keeping requirements; and 5) monitoring and compliance requirements. The first three conditions are specified explicitly in the DAQ's Regional Haze SIP submittal (SIP XX Section D). The other above conditions are contained in three DAQ Approval Orders (AO) for the Huntington and Hunter units 1 and 2. The DAQ Regional Haze SIP specifically requires the implementation of the requirements of the Hunter and Huntington Approval Orders. Both the Regional Haze SIP and the DAQ Approval Orders are federally enforceable and enforceable as a practical matter as defined in the New Source Review Manual (October 1990): "Federally-enforceable refers to all limitations and conditions which are enforceable by the Administrator, including: a) requirements developed pursuant to any new source performance standards (NSPS) or national emission standards for hazardous air pollutants (NESHAP); b) requirements within any applicable federally-approved State Implementation Plan; and c) requirements contained in a permit issued pursuant to federal PSD regulations, or pursuant to PSD or operating permit provisions in a SIP which has been federally approved in accordance with 40 CFR 51 Subpart I" (Review of New Sources and Modifications) (New Source Review Manual (October 1990) p.A.5-6). "Practical enforceability means the source and/or enforcement authority must be able to show continual compliance (or non-compliance) with each limitation or requirement. In other words, adequate testing, monitoring, and record-keeping procedures must be included either in an applicable federally issued permit, or in the applicable federally approved SIP or permit issued under the same." (New Source review Manual p. A.5-6). The Utah Regional Haze SIP will be federally enforceable when approved by EPA and the NSR AO will be federally enforceable both as a component of the RH SIP and as NSR permits. Both the RH SIP and the NSR permits will be enforceable as a practical matter given that DAQ can show continual compliance either through the SIP conditions or the SIP required conditions in the NSR permits. The EPA comment above seems to indicate that if NSR permits can be modified then they are not enforceable. ("EPA does not consider permit conditions adequate to meet this enforceability requirement, as permit conditions may be modified".) The "practical enforceability" requirement is not dependent on the possibility of a permit modification but rather on the ability of the regulating agency to show continual compliance with permits requirements during the effective life of the SIP or permit. If "enforceability as a practical matter" was dependent on the immutability of SIPs and NSR permits than there would not be an enforceable permit anywhere in the country. EPA and DAQ worked in conjunction on the most recent Utah PM10 SIP (submitted September 2005) to develop an "enforceable framework" for the relationship between SIPs and the NSR permit conditions referenced in a SIP. The Regional Haze SIP was developed around the PM10 collaboration and DAQ is uncertain why Region 8 has chosen to unilaterally ignore the progress made on this issue during the development of the PM10 SIP. COMMENT 14 (National Parks Service): In Section D.1 on page 20-24 of the Draft, Utah addresses BART requirements for NOx and direct PM emissions. We agree with Utah's determination of sources subject to BART, since it is based on procedures developed by the WRAP. Table 4 indicates that many Class I areas are affected by emissions from Hunter Units 1 and 2 and Huntington Units 1 and 2 as levels above 0.5 deciviews for the 98th %. Except for Huntington Unit 2, the State has or is permitting the remaining three units (all owned by PacifiCorp) with specific control technologies listed on page 24, and compares those technologies with Presumptive BART limits developed by EPA in 40 CFR 52 Appendix Y. These permitted and proposed emissions limits do not appear to be developed by examining the five BART factors for an appropriate array of alternative control options. A showing that permitted or proposed emission rates are slightly below the presumptive rates established by the EPA in its rulemaking is not sufficient since EPA's costs, a primary factor, were based on industry averages. In addition, there are multiple Class I areas (all those listed in Table 4) likely to see substantial improvements on worst days by control cost higher than the average from these units. Improvement at many Class I areas could warrant control cost higher than average by EPA in establishing the presumptive levels. Fish and Wildlife and Parks: We request Utah to examine a full array of control technologies, the associated costs of these different levels of technology, as well as anticipated improvements in the visibility impacts for the Class I areas listed in Table 4 to fulfill the requirement of a BART determination. We recognize Table 7 (on page 26) presents a "post control" assessment of visibility change based on the emission rates permitted or proposed and that there is little change in the modeled impact. This type of information provided for an array of technologies and their associated costs would address the major regulatory and statutory factors regarding degree of visibility improvement to be expected and cost of controls. STAFF RESPONSE: See Questions 11 and 12 above and Question 15 below. COMMENT 15: (National Parks Service): In addition, Utah should elaborate on the reasons why the sources have such a large impact on the 98th% when assessing whether the source is subject to BART (Table 4), yet controlling emissions to approximately presumptive BART limits show such a small amount of improvement. For example, does Table 7 only represent improvements from changes in NOx and PM? Are the modeling systems used in Table 4 and Table 7 identical? STAFF RESPONSE: Pursuant to 40 CFR 51.308(e)(1)(ii) the State is required to determine which BART-eligible sources are also "subject to BART." BART-eligible sources are subject to BART if they emit any air pollutant that may reasonably be anticipated to cause or contribute to any impairment of visibility in any mandatory Class I Federal area. Both Rocky Mountain Power plants Hunter and Huntington were determined by the State to be subject to BART. The State utilized the technical modeling services of the WRAP Regional Modeling Center (RMC). Modeling was performed according to the RMC modeling protocols. For the WRAP BART exemption screening modeling, the RMC followed the EPA BART Guidelines in 40 CFR 51, Appendix Y and the applicable CALMET/CALPUFF modeling guidance (e.g., IWAQM, 1998; FLAG, 2000; EPA, 2003c) including EPA's March 16, 2006 memorandum: "Dispersion Coefficients for Regulatory Air Quality Modeling in CALPUFF." The basic assumptions of the WRAP BART CALMET/CALPUFF modeling protocols are as follows: 1) three years of modeling (2001, 2002 and 2003) were used; 2) visibility impacts due to emissions of SO2, NOx and primary PM emissions were calculated; 3) visibility was calculated using the Original IMPROVE equation and Annual Average Natural Conditions; 4) the effective range of CALPUFF modeling was set at 300km from the sources; 5) for pre-control modeling maximum 24-hour average actual emissions from the Acid Rain database were used in CALPUFF model; and 6) for post-control modeling expected New Source Review (NSR) permitted limits were used in the CALPUFF model. As outlined in Question 11 and 12 above Appendix Y Part 51 requires coal-fired power plants greater than 750 MW to meet presumptive NOx limits in place of a five factor analysis. DAQ is not required to undertake an extensive series of modeling runs for each feasible BART control option an analysis already completed by EPA as a part of the determination of presumptive limits. BART CALPUFF modeling for the subject to BART determination utilized maximum 24 hour average actual emissions from EPA's Acid Rain (Clean Air Markets) database. Post-control modeling was based on emissions calculated on expected NSR permit limits (Section XX D (6) Table 5).

THIRD AMENDMENT: DAR No. 34350, effective 04/07/2011 -- The following 15 comments were received on this amendment. COMMENT 1 (National Park Service): For Class I areas not on the Colorado Plateau, Section 51.308(d)(1) through (4) are applicable and require demonstration of emission reductions needed to meet the reasonable progress goals for these Class I areas. Utah's long-term strategy needs to address whether additional emission controls for stationary sources beyond those considered for BART are appropriate to provide for reasonable progress at Class I areas outside the Colorado Plateau. Consideration of the WRAP four-factor analysis for reasonable progress would provide general control alternatives for these sources. STAFF RESPONSE: Utah's SIP was developed under Section 309 of the regional haze rule that covers the 16 Class I areas on the Colorado Plateau, including all Class I areas in Utah. Utah's SIP analyzed the emission reductions within Utah to ensure that Class I areas outside of the state were benefiting from Utah's regional haze SIP. Section XX.K.1 of the SIP outlines the significant overall emission reductions in SO2, NOx, and PM in Utah and the region. NOx emissions decline 36% between 1996 and 2018, PM2.5 emissions decline 38%, and SO2 emissions decline 33% during this same time period. Coarse matter emissions are projected to increase, although there is much greater uncertainty in the emission inventories for windblown dust. Taken as a whole, Utah's SIP shows the necessary long-term strategies for Class I areas on the Colorado Plateau, as well as all other Class I areas that are affected by emissions from sources in Utah. Utah has participated in the technical and policy forums of the Western Regional Air Partnership (WRAP) as described in Section XX.M of the plan, and further detailed in Appendix D of the plan. Through that process Utah has shared emissions data and other technical information with other states that have Class I areas that might be impacted by emissions from Utah. The regional haze rule in 40 CFR 51.308(d)(1)(iv) establishes a process for states to consult with upwind states that contribute to visibility impairment in their Class I areas, and includes a process for those states to address impacts from an upwind state that are not adequately addressed by the upwind state's plan. Neighboring states have not identified problems with Utah's SIP through this process. As described above, Section XX.K.1 of the SIP outlines the overall significant emission reductions in Utah, and these reductions will benefit all Class I areas that might be impacted by emissions from Utah. Utah's emissions reductions are included in the overall WRAP modeling analysis and will therefore be reflected in the reasonable progress demonstrations that are prepared by neighboring states. COMMENT 2 (National Park Service): It would be helpful to add an emissions table before the WRAP source apportionment modeling results in Figures 17-19 to illustrate the emission assumptions used in the WRAP source apportionment modeling. Adding the emissions table would explain why mobile source emissions are shown to decrease while point source emissions are shown to increase because the inventory does not include the emission reductions due to BART controls. STAFF RESPONSE: Table 23 was added prior to Figure 17 to compare the inventory used in the source apportionment modeling (shown in Figures 17-19) to the Preliminary Reasonable Progress (PRP) 18a inventory that includes the emission reductions due to the SO2 milestones and BART. COMMENT 3 (National Park Service): Table 21, the labels for VOC and CM are missing. STAFF RESPONSE: Labels for VOC and CM were added to Table 21. COMMENT 4 (National Park Service): On pages 108 and 117, we recommend that you delete the commitment to the final WRAP 2018 inventory and modeling as there is no funding to meet this expectation. STAFF RESPONSE: References to the final WRAP 2018 inventory were deleted. COMMENT 5 (National Park Service): In many places, the SIP references work that the WRAP will provide to implement the SIP. We request to be consulted at the time when Utah assumes any responsibilities assigned to the WRAP in the SIP. STAFF RESPONSE: The SIP outlines Utah's commitment to operate the backstop trading program if the WRAP is not able to perform the functions that were assumed in the SIP. DAQ anticipates that these responsibilities will be met cooperatively with the other Section 309 states. The Section 309 States will work with all stakeholders if future changes are needed to the program. COMMENT 6 (Western Resource Advocates, National Parks Conservation Association, Southern Utah Wilderness Alliance, Utah Physicians for a Healthy Environment) (WildEarth Guardians in comments submitted to WRAP on the proposed changes to the milestones in October 2010): The SIP fails to demonstrate that it will achieve greater reasonable progress than BART for SO2. Utah's SIP contains no BART analysis for SO2 and no explicit determination that the SIP's emission milestones and backstop trading program are better than BART for reducing SO2 emissions. Utah established a BART benchmark based on the claim that the alternative program was designed to meet requirements other than BART. The benchmark was based on EPA's presumptive SO2 emission rate of 0.15 lb/mmbtu. This is not an appropriate benchmark because other western coal fired plants have achieved a more stringent emission rate. Huntington Unit 2 in Utah has an emission rate of 0.12 lb/mmbtu. STAFF RESPONSE: As described in the Better than BART demonstration, the milestones were established to meet the broader reasonable progress goals established by the Grand Canyon Visibility Transport Commission. Because the milestones were developed primarily to meet the broader goal, the regional haze rule in Section 308(e)(2)(c) provides that "the State may determine the best system of continuous emission control technology and associated emission reductions from similar types of sources within a source category based on both source-specific and category-wide information, as appropriate." Presumptive BART was used as the category-wide estimate of the emission reductions achievable due to BART, although in some cases more stringent estimates were used for sources that had already been permitted for other reasons. These estimates were used to establish a benchmark to compare with the alternative program. The milestones meet the benchmark. However, as explained in the document, the milestones provide much greater benefits than would be achieved by BART. The program includes all sources with emissions greater than 100 tons/year of SO2, and most of those sources would not be affected by BART. The program ensures that new source growth will not undermine the progress that is achieved by emission reductions from existing sources. The program also encourages early reductions. COMMENT 7 (WildEarth Guardians in comments submitted to WRAP on the proposed changes to the milestones in October 2010): The Better than BART demonstration claims that the milestones were designed to meet a requirement other than BART. This claim seems a bit absurd. While the 309 Program has not been designed solely to meet BART, the program seems overly implicit, if not explicit, that its requirements are meant to satisfy BART, which is a key statutory component of the Clean Air Act's Regional Haze program. STAFF RESPONSE: The concept of SO2 milestones with a backstop trading program was developed the Grand Canyon Visibility Transport Commission in their 1996 Recommendations. The milestones were part of the overall strategy to address the multiple pollutants and sources that contributed to haze on the Colorado Plateau. The WRAP Market Trading Forum began discussions in 1997 to provide further details for this program. The stationary source strategy was well developed before the BART requirements in the regional haze rule were adopted in 1999. The demonstration that the milestones provided greater reasonable progress than BART was included in the Annex to meet the requirements of the regional haze rule, but BART was a secondary consideration that was added to the underlying stationary source strategy. The overall approach was designed to address the impact from all stationary source SO2 emissions rather than the subset of sources that were subject to BART. COMMENT 8 (Western Resource Advocates, National Parks Conservation Association, Southern Utah Wilderness Alliance, Utah Physicians for a Healthy Environment): WRAP fails to support its contention that emission reductions will happen sooner under the alternative program. BART results in emission reductions no later than 5 years after SIP approval. The regulatory requirement to achieve greater reasonable progress under an alternative program requires greater reductions of visibility impairing pollutants by 2018, not simply earlier reductions. STAFF RESPONSE: The SO2 milestones were adopted in 2003. Sources in the region began making long-term plans to meet the milestones, and many of the reductions have already occurred. Pollution control equipment was upgraded at Huntington Unit 2 in 2006, and more recently at Huntington Unit 1 and Hunter Unit 2. These upgrades were the direct result of Utah's 2003 Regional Haze SIP that established the milestones while allowing companies to manage the specific emission reductions across many units in the most cost-effective manner. There is more to the milestone than the number that is used to define the emission cap. The Greater Reasonable Progress than BART demonstration describes the other elements of the program that work with the emission cap to provide greater reasonable progress than BART in 2018. The milestone applies to all SO2 sources, including older plants that are not subject to BART. There are currently 63 sources included in the program that are not subject to BART. There are only 10 sources that are subject to BART. Emissions from these 10 sources account for 62% of SO2 emissions in 2006 and 31% of SO2 emissions in 2018. The milestone is a mass-based cap that is based on projected actual emissions rather than a permitted emission rate. In addition, the SO2 milestone caps new source growth, a significant control strategy for energy-producing states. COMMENT 9 (Western Resource Advocates, National Parks Conservation Association, Southern Utah Wilderness Alliance, Utah Physicians for a Healthy Environment): The better than BART demonstration expresses SO2 milestones in tons/year. Using average annual emission rates as a milestone is insufficiently protective and fails to show better than BART. Sources frequently emit SO2 pollution at emission rates higher than the average annual rate at the same time. STAFF RESPONSE: The visibility goal is different from the national ambient air quality standards. The goal is expressed in terms of progress rather than meeting a specific ambient concentration. EPA established a metric of the 20% best and 20% worst days to measure progress. Baseline conditions were averaged over 5 years to better represent current conditions. The use of an annual emission rate is consistent with the acid rain program and EPA's proposed Transport Rule. COMMENT 10 (Western Resource Advocates, National Parks Conservation Association, Southern Utah Wilderness Alliance, Utah Physicians for a Healthy Environment) (WildEarth Guardians in comments submitted to WRAP on the proposed changes to the milestones in October 2010): The 309 Program is not enforceable. The program must contain monitoring, recordkeeping, and reporting sufficient to ensure compliance, including through enforcement by citizens, States, and EPA, and must be stated with reasonable specificity so as to ensure consistent compliance by all affected parties. Without such enforcement, the 309 states cannot show that their alternative program is better than BART. We are particularly concerned that it is unclear who, exactly, is responsible for ensuring compliance with the milestones and backstop trading program. Specific sources are not required to achieve emission reductions. There appears to be no specific explanation as to how the milestones will be assured over time. STAFF RESPONSE: The tracking system and backstop trading program that were put into place to ensure that the milestones are met have not been changed since the 2003 SIP and will apply to the revised milestones. During the pre-trigger phase, sources report emissions under Section R307-150-4. The requirements of this rule are enforceable, and have been included in the Title V permits for the applicable sources since the adoption of the SIP in 2003. The Section 309 States have prepared milestone reports annually since 2003 to compare actual emissions to the milestones. These milestone reports are made available for public comment each year prior to being finalized. If the milestones are exceeded, a backstop trading program will be triggered. The details of this program are specified in Rule R307-250 that was submitted as part of the 2003 SIP. This rule is enforceable and specifies the monitoring, recordkeeping and reporting requirements for the trading program. The rule was based on the federal acid rain program regulations. The program is currently enforceable at the state level, and will be enforceable by EPA and citizens when the program is approved into the federal SIPs for each of the participating states. COMMENT 11 (Western Resource Advocates, National Parks Conservation Association, Southern Utah Wilderness Alliance, Utah Physicians for a Healthy Environment): If the backstop trading program is implemented, questions remain as to the party responsible for its operation and the party that would be held accountable in the event that such a program is not implemented effectively. STAFF RESPONSE: The SIP specifies that the State of Utah is responsible for implementing the trading program in Utah. The Section 309 States will determine a program administrator if the program is triggered, but the ultimate authority and responsibility for enforcing the program is maintained by the individual states. Each state is responsible to implement the program within its own jurisdiction. When EPA approves the SIPs, the federally-approved SIP will provide the enforceable mechanism for the regional program. The trading program is designed as a backstop. The SIP describes the infrastructure that would be needed to run the program and includes all of the enforceable regulations, but implementation will not occur unless the program is triggered. If the program is triggered, then elements of the infrastructure, such as the Emission and Allowance Tracking System will be created using technology that is current at the time. The SIP provides adequate time after the program is triggered to put in place the contracts and database systems that would be needed to run a trading program. COMMENT 12 (Western Resource Advocates, National Parks Conservation Association, Southern Utah Wilderness Alliance, Utah Physicians for a Healthy Environment): DAQ has not provided evidence of compliance with 309(g). Utah must demonstrate reasonable progress toward achieving natural visibility conditions in Class I areas outside of the Colorado Plateau. STAFF RESPONSE: All of Utah's Class I areas are included in the 16 Class I areas on the Colorado Plateau. 40 CFR 51.309(g) establishes the requirements for states to demonstrate reasonable progress for Class I areas within their state that are not part of the 16 Class I areas on the Colorado Plateau. Utah is not subject to Section 309(g). Utah's SIP analyzed the emission reductions within Utah to ensure that Class I areas outside of the state were benefiting from Utah's regional haze SIP. Section XX.K.1 of the SIP outlines the significant overall emission reductions in SO2, NOx, and PM in Utah and the region. NOx emissions decline 36% between 1996 and 2018, PM2.5 emissions decline 38%, and SO2 emissions decline 33% during this same time period. Coarse matter emissions are projected to increase, although there is much greater uncertainty in the emission inventories for windblown dust. Taken as a whole, Utah's SIP shows the necessary long-term strategies for Class I areas on the Colorado Plateau, as well as all other Class I areas that are affected by emissions from Utah sources. Utah has participated in the technical and policy forums of the Western Regional Air Partnership (WRAP) as described in Section XX.M of the plan, and further detailed in Appendix D of the plan. Through that process, Utah has shared emissions data and other technical information with other states that have Class I areas that might be impacted by emissions from Utah. The regional haze rule in 40 CFR 51.308(d)((1)(iv) establishes a process for states to consult with upwind states that contribute to visibility impairment in their Class I areas, and includes a process for those states to address impacts from an upwind state that are not adequately addressed by the upwind state's plan. Neighboring states have not identified problems with Utah's SIP through this process. As described above, Section XX.K.1 of the SIP outlines the significant emission reductions in Utah, and these reductions will benefit all Class I areas that might be impacted by emissions from Utah. Utah's emissions reductions are included in the WRAP modeling analysis and are therefore reflected in the reasonable progress demonstrations that were prepared by neighboring states. COMMENT 13 (Western Resource Advocates, National Parks Conservation Association, Southern Utah Wilderness Alliance, Utah Physicians for a Healthy Environment): The SIP improperly defers emissions reductions from oil and gas development. Section K of the SIP states that approximately 90% of current emissions from oil and gas development in Uintah and Duchesne Counties in Eastern Utah occur on land that is under the jurisdiction of the Ute Indian Tribe of the Uintah Ouray Reservation and is therefore not covered by Utah's SIP. The SIP further states that the State of Utah expects that this impact will be addressed in the TIP or FIP that is developed for the Ute Tribe. The Phase III oil and gas inventory shows that 15% of total NOx emissions and 17% of total VOC emissions in Uintah and Duchesne Counties are from sources under Utah's jurisdiction. DAQ may not simply dismiss the impacts of oil and gas development on visibility at Colorado Class I Areas. STAFF RESPONSE: Section K of the SIP establishes the projection of visibility improvement anticipated from the long-term strategy. This section of the SIP was developed and submitted in 2008 based on the information that was available at that point in time. The 2011 SIP proposal adds WRAP PSAT modeling results that were completed in 2006 to more clearly show the impact of Utah sources on neighboring states, but the underlying analysis has not been updated in this SIP revision. The Phase III emission inventory was completed at the end of 2009 and has not been incorporated into any of the WRAP's modeling analyses. However, the regional haze SIP is designed to adapt to new information. The SIP includes progress reports every 5 years (the first progress report will occur in 2013) to assess whether there have been any significant changes in anthropogenic emissions within or outside of the state, and to assess whether the strategies in the SIP are sufficient. A new regional haze SIP is required every 10 years (the next SIP is due in 2018) to ensure continuing progress toward meeting the national visibility goal. There is significant work underway at both the federal and state level to better understand the impact of oil and gas development in the Uintah Basin. High ozone levels have been monitored in the Basin during the winter, and DAQ anticipates that significant emission reductions will occur in the Basin between now and 2018 to reduce ozone levels. This will need to occur in partnership with the Ute Tribe, the Environmental Protection Agency, the Bureau of Land Management, the State of Colorado and local governments due to the multiple jurisdictions in the area. The emission reduction strategies currently in the regional haze SIP apply to all sources in Utah, including those in the Uintah Basin that are under DAQ's jurisdiction. All major point sources are subject to the SO2 milestones and backstop trading program. Vehicle emissions (both on-road and non-road) are decreasing due to new federal regulations. The smoke management strategies also apply in the area. COMMENT 14: Utah's unavoidable breakdown rule undermines the haze SIP. For example, to establish that the 309 program is better than BART WRAP assumes that all sources in Utah will operate within permit terms and conditions. There is no incentive for a facility subject to BART to operate according to its permits. Rather, sources are free to attribute any excess emissions to an unavoidable event and indeed, are free to prolong this event indefinitely and are free from recourse. STAFF RESPONSE: Questions regarding Utah's unavoidable breakdown rule are currently being addressed through EPA's SIP call process. This rule does not undermine the Regional Haze SIP. Utah enforces applicable permits and rules, and applies significant penalties when violations occur. One of the benefits of the SO2 milestones is that all emissions, including emissions during unavoidable breakdowns or excess emissions when a source is in violation of its permit, are included in the emission inventory that is compared to the milestone. There is no distinction between unavoidable emissions and excess emissions in this process. These provisions are outlined in Section R307-150-4. COMMENT 15: There were a number of detailed comments received on the BART determination for NOx and PM that was completed in 2008 and is described in Section D.6 of the SIP. These comments are outside the scope of the January proposal and apply to work that was completed as part of the 2008 SIP. STAFF RESPONSE: DAQ staff recommended that the Board reserve the detailed comments that have been received on the BART analysis for BART and PM for consideration at a later date, after EPA completes action on the Regional Haze SIP.

FOURTH AMENDMENT: DAR No. 34351, effective 05/04/2011 -- The following comments were received on this amendment: Comment II.1: While not a formal or final analysis, EPA raised concerns that the proposed revision to the SIP to allow for Kennecott's BCM expansion will not be approvable. Citing Section 110(l) of the Clean Air Act, EPA says it "shall not approve" a SIP revision if it would interfere with any applicable requirement concerning attainment and reasonable further progress. This is pertinent not only to the National Ambient Air Quality Standards (NAAQS) for PM10 says EPA, but to other NAAQS as well, in particular PM2.5, ozone, and NO2. (Comment made by the EPA). DAQ Response - DAQ disagreed with EPA. The state was modifying a PM10 maintenance plan. A maintenance plan requires a demonstration of adequacy. Under EPA regulations such a plan "must demonstrate that the measures, rules, and regulations contained in it are adequate to provide for the timely attainment and maintenance of the national standard that it implements." 40 CFR Section 51.112(a). At issue before the Board is whether the increased material moved at the Bingham Canyon Mine (BCM) will still allow the 2005 PM10 plan to make the demonstration of adequacy for PM10. Based on the staff's review of Kennecott's proposal, the revised 2005 SIP can still make the adequacy demonstration because the air quality models do not predict that PM10 concentrations will exceed the PM10 standard at any location in current or future years. Second, as to the applicability to other NAAQS under section 110(l), EPA's comment is inconsistent with its own prior practice. When Utah submitted its ozone SIP, EPA did not object that the ozone SIP did not address PM10, and when Utah submitted its maintenance plan for PM10 in 2005, EPA did not object that it had not considered the ozone NAAQS. EPA did raise section 110(l) as part of its comments on the 2005 PM10 maintenance plan, but in each case it was only with regard to PM10 - not other NAAQS. Finally, KUC has initiated a parallel process to amend its approval order, which request is governed by a separate set of rules and is currently under review by DAQ. That review will consider the potential impacts on other air pollutants in addition to PM10. The Executive Secretary's decision on whether to amend KUC's approval order is in part dependent on whether the Air Quality Board approves the proposed amendment to the PM10 Maintenance Plan. Comment II.2: EPA, citing its 01/08/2010 comment letter, clarified that the federally enforceable limit applicable to material that may be moved at the BCM is 150.5 million tons per year, as contained in the 1994 PM10 SIP. EPA also referenced its 1999 and December 2009 comments on the inadequacy of Utah's PM10 SIP and contends that those comments also relate to the SIP revision under consideration (Comment made by the EPA). DAQ Response - DAQ disagreed with EPA's assessment of the federally enforceable limit. In 1999, the 1994 limit affecting the amount of material that could be moved at the mine, 150.5 million tons per year, was revised in Approval Order UDAQE-801-99 and increased to 197 million tons per year. That AO was approved by the Air Quality Board. In 1999, this (Board approval) was a mechanism provided in the EPA-approved 1994 Utah SIP for changing specific limits, such as the limit for the BCM, in the 1994 SIP. The item pending before the Board was whether the 2005 PM10 SIP should be revised, to allow an increase in the amount of material moved at BCM from 197 millions tons to 260 million tons per 12-month period. As noted above, under the 1994 SIP, the Air Quality Board could increase a source's limit specified in the SIP if, first, the source's AO was revised and approved by the Executive Secretary, and then approved by the Board. That option was no longer available under the 2005 SIP. In DAQ's view, for a source to increase a limit specified in the SIP, the Air Quality Board must amend the maintenance plan (the 2005 SIP), provided the State can still make an adequacy demonstration required by 40 CFR Section 51.112(a). There is often a lag time of many years between the State's submittal of a SIP to EPA and EPA's final action on that submittal. In the interim, business in the State must be able to proceed, provided there is compliance with applicable air quality regulations. That is the case here. As EPA has not taken final action on the 2005 SIP revision (but has issued a notice of intent to disapprove it), and as the 2005 SIP is existing State law, the Board had two options: amend the 2005 SIP to increase the limit applicable to Kennecott or require Kennecott to conduct business within the limit currently in the 2005 SIP which was established pursuant to the 1994 SIP. On the technical merits, DAQ recommended that the Board approve the increased limit because the 2005 SIP could still meet the adequacy demonstration required by 40 CFR Section 51.112(a). Comment II.3: The TSD has been revised twice, while the NOI has not been revised. These changes have not been documented in a formal way by DAQ. UPHE requests that DAQ provide to the public the agency's full technical analysis of information presented in the TSD (Comment made by UPHE). DAQ Response - DAQ's technical analysis is and has been available to the public. The final TSD released for public comment is the document that DAQ relies upon to show that the 2005 SIP may be amended as proposed. In particular, the DAQ is relying on the TSD Section 3, 2005 Maintenance Plan Demonstration and Section 4, Emissions Summary. Other parts of the TSD and references made therein corroborate and support the proposed increased limit. Prior to being finalized, the TSD was a dynamic document, updated and revised by Kennecott to satisfy the staff's analysis that the proposed changes met the regulatory requirements to revise the SIP. On the permitting side, a similar process occurred with the NOI, which was also revised. Comment II.4: The administrative processing of the proposed AO has been difficult from the standpoint of an AQB member who had been advised to avoid involvement with the AO, in order to preserve the ability to participate in adjudication of the permit, in the event that it is subsequently challenged. Yet, the SIP TSD refers to some elements of the SIP background contained within the permitting documentation (Comment made by Kathy Van Dame, UAQB member). DAQ Response - All documents relevant to the Kennecott expansion project have been posted on DAQ's website, including the TSD for the SIP, the NOI for the AO and the Executive Secretary's Intent to Approve the AO; as well as public comments received on the SIP and AO actions. There is no restriction on any Board member reviewing any of the information posted on the DAQ website. However, the action the Board will take is based on the record for the SIP. That record includes the TSD and where, for example, the TSD cross-references the information and calculations in the NOI, that information forms part of the record for the SIP. Comment III.A.1: Kennecott's CALPUFF modeling analysis in the Technical Support Document (TSD) did not consider any NAAQS but PM10 (see Comment No. II.1) and was based on the 2005 UAM-AERO modeling effort (part of the Utah's proposed maintenance plan for PM10). EPA Region 8 has proposed to disapprove this plan, in part because of issues with the UAM-AERO modeling. Thus, the current modeling is also inadequate for some of the same reasons cited in the proposed disapproval (see FR 74, No. 229, pp 62717), including the modeled release point of banked emissions and lack of speciated relative response factors. Furthermore, there is insufficient information for both CALPUFF and AERMOD simulations described in the TSD. The impacts of the proposed BCM expansion should be evaluated using the new CMAQ model and additional AERMOD simulations with updated emissions data (Comment made by the EPA). DAQ Response - Taken point-by-point: - "Kennecott's CALPUFF modeling analysis in the Technical Support Document (TSD) did not consider any NAAQS but PM10 (see Comment No. II.1)" Response: DAQ agreed that it only considered PM10, but disagreed that the modeling was inadequate for that reason. The CALPUFF analysis is specific to the PM10 standard because that is the focus of the UAM-AERO modeling for the maintenance plan. The CALPUFF analysis was designed to show that additional emissions from the KUC expansion would not increase PM10 concentrations above the design value of 150 ug/m3 used in the UAM-AERO analysis. - "...was based on the 2005 UAM-AERO modeling effort (part of the Utah's proposed maintenance plan for PM10.) EPA Region 8 has proposed to disapprove this plan, in part because of issues with the UAM-AERO modeling. Thus, the current modeling is also inadequate for some of the same reasons cited in the proposed disapproval (see FR 74, No. 229, pp 62717), including the modeled release point of banked emissions and lack of speciated relative response factors." Response: In the reference, FR 74, No. 229, pp 62717, there are three comments that are specifically related to the UAM-AERO modeling. They are detailed in FR 74, No. 229, pp 62722 - 62724 under the heading: "1. Deficiencies applicable to all three maintenance plans." All three of these comments were addressed by DAQ in responses to EPA in February 2010 - "Concerning EPA proposed disapproval of PM10 Plan.doc" pp 8 - 11, attached). - "Furthermore, there is insufficient information for both CALPUFF and AERMOD simulations described in the TSD." Response: DAQ disagreed with this comment. The summary information was included in the TSD as governed by the demonstration of adequacy requirements contained in 40 CFR Section 51.112(b). The demonstration must include the following: 1) a summary of the computations, assumptions, and judgments used to determine the degree of reduction of emissions (or reductions in the growth of emissions) that will result from the implementation of the control strategy; 2) a presentation of emission levels expected to result from implementation of each measure of the control strategy; 3) a presentation of the air quality levels expected to result from implementation of the overall control strategy presented either in tabular form or as an isopleth map showing expected maximum pollutant concentrations; and 4) a description of the dispersion models used to project air quality and to evaluate control strategies. The TSD satisfied all four requirements, and is therefore sufficient for DAQ's review. - The impacts of the proposed BCM expansion should be evaluated using the new CMAQ model and additional AERMOD simulations with updated emissions data. Response: - The technical analysis for this project was initiated close to two years ago. At that time the CMAQ modeling analysis for PM2.5 was in its initial phases and was rejected as a viable approach since its completion date was too far out in the future. The best technical approach available was through the use of CALPUFF and AERMOD. Comment III.A.2: Section 3 of the TSD discusses the 2005 SIP revision. While approved by the UAQB, a SIP is a federally-enforceable document, and as such, must be approved by EPA. Not only has EPA not approved the 2005 SIP, but has published its intention to disapprove the SIP on numerous grounds, including issues with the UAM-AERO modeling that supports the plan. Therefore, Section 3 of the TSD is technically moot. Nevertheless, we raise the following issues concerning the technical details presented in Section 3 (Comments made by UPHE). DAQ Response - The UAM-AERO modeling files are available from DAQ; however, the model itself is not available. DAQ transitioned to the current generation of photochemical air quality model (the Community Multi-scale Air Quality Model (CMAQ)) soon after the technical work on the PM10 Redesignation Request was completed in 2005. That model was coded for and compiled on computers that are no longer in use at DAQ or elsewhere. By the same token the input files used for that model are not compatible with this newer class of models. All of the input and output files from that modeling exercised are still archived at DAQ and applicable files needed to apply the CALPUFF results to the UAM-AERO modeled concentrations were provided to KUC. DAQ did not switch modeling platforms, but used both platforms to derive the cumulative impact from all sources including those from the Bingham Canyon Mine expansion. The CALPUFF modeling system contains algorithms for the chemical transformation of precursors to secondary PM10. In the Bingham Canyon Mine expansion analysis the NOx emissions were fully converted to PM10. Using 100% conversion assumes a conservative, i.e., worst case scenario. The differences reported in tables 3-3 and 1-1 are not related to the inclusion, or not, of the Copperton Concentrator. Rather, Table 3-3 reports the two inventories used to make the adequacy demonstration with respect to the 2005 maintenance plan. One is the inventory used in that plan for the UAM-AERO demonstration (at 197 Mtpy) and the other is an assessment made, using the same emissions calculation methodology, assuming a material-moved limit of 260 Mtpy. Pit retention was not considered in making the adequacy demonstration with respect to the 2005 maintenance plan required by 40 CFR Section 51.112(a.). The inventory ummarized in Table 1-1 also assumes a material moved limit of 260 Mtpy, but was compiled using the emissions calculation methodology included as part of the NOI (Appendix B.) The totals in this table reflect the application of a pit retention factor, whereas neither of the two inventories summarized in Table 3-3 made that assumption. UAM-AERO results can be deduced through simple subtraction of data provided in Table 3-5 and Table 3-6 on page 3-7 of the TSD. Column 5 in both tables represents the increase in emissions due to the added emissions from the mine expansion. Column 4 in each table represents the UAM-AERO estimate plus the additional concentration from Kennecott. The difference of subtracting column 5 from column 4 will give the UAM-AERO results for the maximum grid cell in the domain. Figures 3-1 and 3-2 on the page 3-8 and page 3-9 show the same data in a graphical format. Comment III.B.1: Section 2.1 of the TSD states that secondary sulfate and nitrate impacts were assumed to be in direct proportion to a source's relative sulfur dioxide and nitrogen oxides emissions. The 1994 SIP describes Kennecott as a large source of secondary PM10. The commenter requests that DAQ describe the meaning of this statement and show where the results of the demonstration account for secondary pollutants (Comment made by UPHE). DAQ Response - The 1994 SIP used Chemical Mass Balance (CMB) modeling to show attainment. CMB is well suited to apportioning source contribution for primary PM, but secondary PM (e.g., ammonium sulfate and ammonium nitrate), having undergone transformation between source and receptor, poses problems. To work around this problem, all of the secondary sulfate and nitrate collected on the filters was apportioned based on the emissions inventory. Kennecott's inventory showed large amounts of SO2 and NOx, hence it was considered a large source of secondary PM10. Comment III.B.2: Section 5 (Conclusion) of the TSD discusses, in the first bullet item, an analysis based on the 1994 SIP supporting the modification of the operational limit at the mine from 150.5 Mtpy to 260. The commenter can find no evidence of this type of analysis, and asks if it was performed previously (Comment made by UPHE). DAQ Response - This topic is first discussed in Section 2.2 of the TSD. The 1994 SIP was built with a limit of 150.5 Mtpy, and the first column reported in Table 2-1 (1994 emission inventory used in the CMB modeling) reflects that limit. The next column shows the emissions as they would have been calculated in 1994, had the limit been 260 Mtpy. The increase is shown in the third column, and this is the basis that was used as the accounting for offsetting with banked emissions. Comment III.B.i.l: The proposed use of banked emission credits, the TSD identifies a total emissions increase of 5,417 tons per year that includes increases of both PM10 and NOx. To offset this increase, Kennecott proposes to apply banked SO2 credits. The credits were generated at the smelter, which is 25 miles away from the pit, and had been released from the 1,200 foot stack. The proposed inter-precursor trade has not been modeled to demonstrate the effect on ambient air quality. Additionally, EPA has previously asked the State to provide evidence to validate the banked credits and identified concerns with the 1994 PM10 SIP's offset provisions (Comment made by the EPA). DAQ Response - Kennecott was required by the 1994 SIP to reduce emissions. In 1999, KUC was credited for modernization efforts undertaken while operating in compliance with this SIP. This modernization resulted in Kennecott banking 17,656.50 tons of actual SO2 emissions reductions. The offsets were attained from emissions reductions in the same on attainment area as the BCM and are therefore valid banked emissions (Section R307-403-4). The offsetting rule (Section R307-403-5) developed for and approved by EPA in the 1994 PM10 SIP combines PM10, SO2, and NOx, and allows for inter-pollutant trading for minor sources. For an increase of emission greater than 50 tons per year, a 1.2:1 ratio is required in the nonattainment area. In accordance with the offsetting rule, the total emissions increase of 5,492 tons per year is being offset with 6,590 tons of banked SO2 emissions (see TSD Section 2.2.3.). If the proposed SIP revision is approved by the Air Quality Board, then these offsets will be made enforceable at the time the approval order is finalized. See also response to Comment No. V.C.1. Comment III.B.i.2: Citing EPA's 6/30/99 letter Re: "Intent To Approve" Production Increase for Kennecott Bingham Canyon Mine, which proposed to increase the amount of material moved from 150.5 Mtpy to 197, and wherein there was a discussion concerning the application of banked credits in order to offset the projected increase in emissions, EPA stated that, according to State banking letters to Kennecott, the banked credits were generated based on the difference between the annual emissions allowed in the PM10 SIP and the emissions subsequently allowed by the Approval Order for those operations. And, while acknowledging this practice to be in accord with Section R307-403-7, it does not constitute evidence that actual emission reductions have occurred. Under Subsection R307-403-4(2), any emission offsets shall be in terms of actual emissions, yet no evidence has been provided that there has been a reduction of at least 1,105 tpy in actual emissions (Comment referencing EPA's earlier comment; Terry Marasco). DAQ Response - See response to Comment No. III.B.i.1. Comment No. III.B.i.3: Concerning Kennecott's proposed use of banked SO2 credits, the record does not support the claim that the offsets will provide a positive net air quality benefit in the affected area of nonattainment as required by Subsection R307-403-3(3)(d.) (Comment made by Western Resource Advocates). DAQ Response - This comment is specific to the Executive Secretary's Intent to Approve (UDAQE-IN0105710028-11, dated 02/02/2011), the NOI, and the associated New Source Plan Review. A detailed response will be provided as part of that record. Comment No. III.B.i.4: Kennecott has offered emission reduction credits to offset increases in emissions. Since offsets do not appear to be required by state or federal law, DAQ should explain the regulatory basis for the application of these credits to the SIP modification process (Comment made by UPHE). DAQ Response - This comment is specific to the executive Secretary's Intent to Approve (UDAQE-IN0105710028-11, dated 02/02/2011), the NOI, and the associated New Source Plan Review. A detailed response will be provided as part of that record. Comment No. III.B.i.5: Section 2.2 of the TSD presents the proposal to offset increases in PM10 and NOx. The credits currently represent emissions that are banked and are not being emitted into the airshed. However, the Salt Lake area has experienced exceedances of the PM10 standard even while these credits are in the bank. Using these banked 13 credits to allow additional emissions is roblematic and should not be allowed by DAQ (Comment made by UPHE). DAQ Response - DAQ disagreed, and continues to believe that the efforts made as part of the 1994 PM10 SIP have resulted in attainment and continued maintenance of the NAAQS. The form of the 24-hr PM10 standard does allow for, on a 3-year average, one exceedance per year. Exceedances monitored beyond that have been due to what DAQ characterizes as exceptional events, meaning that exceedances would have been monitored irrespective of our anthropogenic (man-made) emissions. Typically, these are very windy days, often in spring when melt/freeze conditions have rendered surface soils in surrounding desert areas available for transport. Add to those conditions a turbulent frontal passage and there will be a monitored exceedance of 150 microgram/m3. DAQ acknowledges that EPA has not always agreed with its interpretation of these events, nevertheless, for the reasons described above, DAQ does not feel that the exchange of these credits will add to the number of PM10 exceedances. C. Overlap between 2005 SIP and Intent to Approve UDAQE-IN0105710028-11 (dated 02/02/2011) and Associated New Source Plan Review. Comment No. III.C.1: In Section 4.2.5 of the TSD, Kennecott states that it follows DAQ's policy (Permitting Branch Memo from R. Olsen, 03/10/2008) of using 75% control efficiency on fugitive emissions from unpaved roads. However, the calculations shown in Table A1-18 show the application of 85 and 95% control, reflecting differences in seasonality. These emissions should be re-calculated using 75% control (Comment made by UPHE). DAQ Response - DAQ disagreed. A control efficiency of 95% was used for calculating the fugitive emissions from the haul roads when the 1994 and 2005 PM10 SIPs were developed. To remain consistent, these same control efficiencies were used when the TSD was written. Table A1-18, and all other calculations shown in Appendix A1of the TSD, are consistent with the calculations used in the 1994 attainment SIP. The NOI follows a different regulatory process which has different requirements. Therefore, the emissions that were calculated for the NOI process followed the guidelines outlined in the memo developed for the NOI process. That memo recommends that a 75% control efficiency be used for calculating the haul road fugitive emissions used in the NOI process. Comment No. III.C.2: Table 1-1 of the TSD reports the "most representative" PTE calculations for 260 Mtpy. However, the PTE summary presented in the companion" NOI document does not agree with the summary given in Table 1-1. This discrepancy casts doubt as to the accuracy of both sets of numbers (Comment made by UPHE). DAQ Response - DAQ disagreed. Both documents were modified since they were originally submitted to DAQ in August 2010. The TSD and NOI were reviewed by different individuals, which resulted in the documents being updated at different times. The most current versions were posted on the DEQ/DAQ web site in January 2010. Comment No. III.D.1 - DAQ's 2008 emissions inventory, representing activities constrained by a 197 Mtpy operational limit, reports 2,915 tons of PM10 from the mine/concentrator. Kennecott's TSD states that with a proposed operational increase of 32% the total PM10 emissions will only be 1,513 tpy, a 48% decrease. The record does not support such a claim. There are no new methods of pollution control. It is perhaps more reasonable to assume that a 32% increase in operational mining will lead to a commensurate increase in actual emissions (Comment made by UPHE). DAQ Response - The action before the Board is whether to revise section IX.H.2.h of the 2005 PM10 Maintenance Plan by changing the amount of material KUC may move at the mine from 197 Mtpy to 260. In order that such action be taken, 40 CFR Section 51.112(a) requires a demonstration of adequacy with respect to the PM10 NAAQS. This demonstration was made using CALPUFF, in conjunction with the UAM-AERO demonstration underlying the 2005 PM10 Maintenance Plan. The analysis has been documented in section 3 of the TSD. The emissions inventories used to make this demonstration show that there will be an increase in emissions from what had been relied upon in the 2005 Plan. Some discussion concerning these numbers is necessary. The 2005 PM10 Maintenance SIP inventories show a comparison between the Post-SIP allowable emissions estimate used in the 2005 maintenance SIP and the calculation appearing in Appendix A-2 of the TSD. The 2005 SIP calculation was based on an annual limit of 197 Mtpy of material moved. The TSD calculation uses methods and assumptions that are consistent with the inventory supporting the 2005 maintenance SIP, but assumes a limit of 260 Mtpy. The difference in emissions between these two estimates is what was modeled using CALPUFF and then added to the UAM result. Neither of these inventories assumes any pit retention. The assumption to use calculation methodologies that are consistent with those in practice when the maintenance demonstration was made is sound. The (2005) UAM16 AERO model was calibrated using base-year inventories for KUC and every other source that were calculated using these practices. This assumption makes comparisons with post-SIP inventories used in the respective demonstrations acceptable. With regard to the question as to whether there should be an emissions increase that is proportional to the increase in material moved, there are several improvements in the operation of the mine that can be expected with this proposal. Most notable is the new requirement to apply chemical dust suppressant to those portions of the haul roads outside of the pit where the waste rock is to be hauled. In 1999, engines used in the haul trucks used what is referred to as a pre-tier 0 engine. Since then EPA has required all new engines that are being developed to use cleaner burn technologies. Kennecott uses engines now that are equipped with tier 1, tier 2, tier 3 and tier 4 technologies. These new engines have reduced the NOx emissions from the engine exhaust. When the SIPs were developed, the sulfur content of the diesel fuels were 500 ppm and with the new federal requirements the sulfur content of the sulfur has been reduced to 15 ppm. When the SIP emission calculations were performed the roads were dustier due to the silt loading in the haul roads. Now Kennecott has installed a road base crusher and places a road base mix on the haul roads which has reduced the silt content of the road surface. This has reduced the fugitive dust emissions from the haul roads. All of the technologies outlined above have reduced the PM10, SO2 and NOx emissions from the Bingham Canyon Mine. E. Air Flow Patterns and Pit Retention of Fugitive Dust for the Bingham Canyon Mine (Bhaskar and Tandon, 1996). Comment No. IV.1: Many commenters expressed their opposition to the proposed increase in activity at the Bingham Canyon Mine (BCM.) DAQ lists the comments point by point, then responds to these comments below. DAQ Response: As an initial matter, some questions have been raised about the specific responsibilities of DAQ and the Utah Air Quality Board. The policy and purpose of the Air Conservation Act is set out below: Section 19-2-101. Short title -- Policy of state and purpose of chapter -- Support of local and regional programs -- Provision of coordinated statewide program. (1) This chapter is known as the "Air Conservation Act." (2) It is the policy of this state and the purpose of this chapter to achieve and maintain levels of air quality which will protect human health and safety, and to the greatest degree practicable, prevent injury to plant and animal life and property, foster the comfort and convenience of the people, promote the economic and social development of this state, and facilitate the enjoyment of the natural attractions of this state. (3) Local and regional air pollution control programs shall be supported to the extent practicable as essential instruments to secure and maintain appropriate levels of air quality. (4) The purpose of this chapter is to: (a) provide for a coordinated statewide program of air pollution prevention, abatement, and control; (b) provide for an appropriate distribution of responsibilities among the state and local units of government; (c) facilitate cooperation across jurisdictional lines in dealing with problems of air pollution not confined within single jurisdictions; and (d) provide a framework within which air quality may be protected and consideration given to the public interest at all levels of planning and development within the state. Comment IV.1.a: The role of the DAQ and its Board is to protect the health of Utah's citizenry and to bring the State into compliance with Federal health standards. Economic consequences are not to be considered. DAQ Response: Economic consequences or concerns played no role in DAQ's review. As noted in DAQ's response to Comment II.1. above, DAQ proposes to modify a PM10 SIP maintenance plan. To do so, a maintenance plan requires a demonstration of adequacy. Under EPA regulations such a plan "must demonstrate that the measures, rules, and regulations contained in it are adequate to provide for the timely attainment and maintenance of the national standard that it implements." 40 CFR Section 51.112(a). The Clean Air Act, its implementing regulations and the Utah Air Conservation Act all presume that business activity that impacts air quality will occur. The proposal for the Board's consideration has made the necessary demonstration of adequacy, and therefore is consistent with the requirements of applicable law to protect the health of Utah's citizenry. Comment IV.1.b: Parallel processing of the AO and the SIP imply that the proposed SIP revision is a forgone conclusion. DAQ Response: Please see responses to Comments No. II.4 and V.A.1. Comment IV.1.c: Particular hardship imposed upon those suffering from asthma, developing children, and nearby residents of Hi-Country Estates, described as dusty already. DAQ Response: The Clean Air Act, its implementing regulations and the Utah Air Conservation Act all presume that business activity that impacts air quality will occur. The proposal for the Board's consideration has made the necessary demonstration of adequacy, and therefore is consistent with the requirements of applicable law to protect the health of Utah's citizenry. Comment IV.1.d: Any perceived benefit to the economy should be tempered by a discussion of the associated increase in health care costs. Additionally, Kennecott's gain may result in additional constraints on other existing businesses as we attempt to solve our problems with PM2.5 and ozone. DAQ Response: Please see response to Comment IV.1.a, above. In addition, PM2.5 and ozone will be reviewed during SIP revision actions for those specific pollutants. Please see response to Comment No. IV.3, below. Comment IV.1.e: Kennecott provides relatively few jobs while greatly contributing to industrial air pollution. Breathable air is more important than economic gain. DAQ Response: Please see response to Comment IV.1.a, above. Comment IV.1.f: A company that shows a profit of $14 billion should be investing in technologies to pollute less. If Kennecott could reduce an equal amount of particulate emissions from other sources they could proceed with their plans. DAQ Response: The question for the Air Quality Board is whether the appropriate demonstration has been made with regard to the effect the proposed increase in total material moved would have on the 2005 PM10 Maintenance Plan. DAQ has reviewed the proposal and believes that the demonstration of adequacy has been made. Accordingly, KUC has met the necessary requirement for the amendment to the 2005 plan. Considerations of lower-polluting technologies beyond KUC's current regulatory obligations are not a subject of this action. Comment IV.1.g: Approval for the Cornerstone Project to move forward should be reserved until the EPA takes action (by 12/01/2011) on the States proposed maintenance plan for PM10. DAQ Response: Please see responses to Comments No. II.2 and V.A.2. Comment IV.1.h: Air quality along the Wasatch Front is already not meeting the federal health standards for PM10, PM2.5 and ozone. This is especially true during wintertime when Utah's air quality is often characterized as "worst in the nation." These episodes coincide with incidences of poor health. We should therefore be looking for ways to reduce our emissions rather than allowing for projects such as this which would make the current situation worse. DAQ Response: Please see response to Comment IV.1.a, above. Comment IV.1.i: Despite the PM10 SIP that is in place, Salt Lake County has still exceeded the 24-hr standard for PM10 based on monitored values that DAQ considers exceptional events. This indicates that the current SIP is not protective enough. DAQ Response: Please see response to Comment No. III.B.i.5. Comment IV.1.j: Kennecott claims that the Cornerstone Project will actually reduce air pollution along the Wasatch Front. However the company has projected no credible documentation to support the assertion that their increased hauling of ore and waste will not yield a proportionate increase in particulate pollution. DAQ Response: Please see response to Comment No. III.D.1. Comment IV.1.k: Kennecott's assertion that 80% of the emissions never leave the pit are based on a paper written by a University of Utah graduate student that has never been verified or field tested, even as its author advised it should be. DAQ Response: Please see Editorial Note in section III.E. Comment No. IV.2: Many commenters expressed their support for the proposed increase in activity at the Bingham Canyon Mine (BCM.) Reasons given for this support included: jobs, economic development, and Kennecott's charitable contributions and community development. DAQ Response: These commenters were all in favor of the Kennecott BCM expansion and did not present a technical reason for their support. Since the comments are editorial and not technical in nature, DAQ acknowledges the comments but does not change its recommendation that the Board approve the proposed revision to the 2005 Maintenance Plan. Comment No. IV.3: The Utah Air Quality Board should reserve its decision and require further analysis of the impacts on air quality with respect to PM2.5 due to current and future mine operations. Kennecott's proposal would seemingly result in an increase of NOx emissions. NOx is a precursor to both PM10 and PM2.5 (Comment made by Ralph Becker, Mayor, Salt Lake City and Peter Corroon, Mayor, Salt Lake County). DAQ Response: As required by the Clean Air Act, air quality standards are in a constant state of review and have become more stringent over time. Each time EPA revises a standard, a timeline is established to allow states to develop the tools and evaluations necessary to draft a SIP to address that pollutant. The development of the PM2.5 SIP is well underway but is not required to be complete until the end of 2012. The SIP process contains the authority to require controls adequate to provide for the timely attainment and maintenance of the PM2.5 NAAQS. The action before the Board does not impede the development of a future PM 2.5 SIP. The contribution to fine particulate made by NOx emissions will be part of the PM2.5 evaluation. KENNECOTT'S COMMENTS. A. LEGAL AND PROCESS RELATED COMMENTS. Comment No. V.A.1: Kennecott submitted a request to modify the current material movement limitation in both the state 2005 PM10 SIP and the Bingham Canyon Mine Approval Order to ensure the public has sight of the entire proposal. Both requests were submitted to the DAQ for a parallel but staggered review (Comment made by KUC). DAQ Response - See Introduction and Responses in Section II above. DAQ sent the revision to the 2005 SIP and a modification of the existing Approval Order out for public comment at the same time with the view that it would enhance the public's understanding of all the regulatory actions that needed to be taken to approve Kennecott's request. In order for Kennecott to proceed with its project, both actions need approval, but, importantly, an Intent to Approve document does not pre-suppose approval of the proposed SIP revision. (See also Comments grouped under section III.C.) Comment No. V.A.2 - The 2005 SIP rulemaking does not need to wait for EPA approval because it is a matter of Utah state law. The rulemaking pertains only to the state 2005 PM10 SIP (Comment made by KUC). Response - The 2005 maintenance plan was approved by the AQB and is enforceable as a matter of state law. Accordingly, promulgated by the Board as state law, the mechanism to amend the PM10 Maintenance Plan is also by state law. The PM10 SIP was submitted to EPA in 2005, but EPA has not yet taken final action. The Air Quality Board approved the PM10 Maintenance plan in 2005, which shows that the Board was satisfied that the PM10 standard would not be violated. The proposed amendment to the plan would change one limitation in the Board-approved plan, which is supported by an adequacy demonstration that with the amendment complies with the attainment demonstration approved in 2005. Should the Board approve Kennecott's proposal as a matter of state law, it too would need to be submitted to EPA for the agency's consideration. EPA proposed (in 2010) to disapprove the 2005 SIP revision. Given that several years often pass between Utah's SIP submissions and EPA's final actions, DAQ does not consider it prudent to delay this rulemaking in order to resolve broader disagreements with EPA. Comment No. V.A.3: The TSD submitted to DAQ is intended to demonstrate continued compliance with the PM10 NAAQS in accordance with the respective technical analyses that formed the bases for the attainment and maintenance demonstrations contained in the l994 PM10 SIP and the 2005 PM10 Maintenance plan. Because the SIP rulemaking is limited to modifying the 2005 PM10 SIP, only PM10 and its precursors (SO2 and NOx) were included in the analysis. Additionally, to support the 1994 SIP modification, KUC is proposing to offset its PM10 and NOx increases from all emission sources on a voluntary basis in a manner consistent with the offsetting provisions of the 1994 SIP and the Utah Administrative Code. - The Chemical Mass Balance (CMB) receptor model, in conjunction with emissions control and offset requirements, was used in support of the federal 1994 SIP attainment. To offset the emissions increase associated with the BCM expansion 5,485 tons of banked stack-level SO2 emission credits will be relinquished in addition to the 1,105 tons of banked PM10 and SO2 credits already relinquished in 1999 (when the limitation on material moved was revised from 150.5 Mtpy to 197.) The analysis shows that the increase in the material-moved limitation is consistent with and satisfies the 1994 attainment and maintenance demonstration. - The UAM-AERO model was used in support of the 2005 maintenance demonstration. Added to that result was a CALPUFF analysis that assumed no pit retention and conservatively assumed a 100% conversion rate of NOx to nitrates (secondary particulate matter). The analysis shows that increases to the UAM-AERO-modeled NOx and primary PM10 will not cause any grid cell to exceed the total PM10 NAAQS of 150 microgram/m3. - Additionally, Kennecott has made a third technical demonstration related to ambient air quality in the immediate vicinity of the mine using the AERMOD model. Despite some conservative assumptions that resulted in the modeling of 30,986 vehicle miles traveled (vmt) per day, despite a daily limit of 30,000 vmt, the analysis demonstrates that the proposed modification will not result in a violation of the 24-hr PM10 NAAQS in the near field. The three technical demonstrations show that the proposed increase in the materialmoved limitation will not adversely affect attainment and maintenance of the PM10 NAAQS (Comment made by KUC). DAQ Response - Kennecott has looked at the PM10 NAAQS from several different standpoints, each in an effort to show that its proposal would not interfere with attainment or maintenance thereof. From the standpoint of the federally approved 1994 attainment SIP, KUC has used emissions calculation methods consistent with those used to support the underlying demonstration of attainment in order to evaluate the increase in material moved at the mine (see TSD Section 2 and Appendix A-1.). The increase in emissions calculated thereby was offset in a manner consistent with the rule adopted as part of that SIP which required, for sources or modifications resulting in an increase of (PM10 + SO2 + NOx) totaling at least 50 tpy, offsets at a ratio of 1.2:1. The offsets were applied to insure that KUC's proposed emissions, including tailpipe and fugitives, would not compromise the attainment demonstration underlying the 1994 SIP. The banked credits used to make this offset were generated by exceeding the emission reductions required by that 1994 demonstration. From the standpoint of the state-approved 2005 maintenance SIP, KUC has used the emissions calculation methods consistent with those used to support the underlying demonstration of maintenance in order to evaluate the increase in material moved at the mine (see TSD Section 3 and Appendix A-2.). The increase in emissions calculated thereby was modeled using CALPUFF and added to the concentrations predicted by the underlying maintenance demonstration. Given the impossibility of re-running UAM-AERO, DAQ endorses this approach. The AERMOD demonstration is not required to satisfy the demonstration of adequacy requirement of 40 CFR Section 51.112(a). With respect to the AERMOD demonstration, neither the 1994 attainment demonstration nor the 2005 maintenance demonstration includes any analysis such as this, which might be termed a "hot spot" analysis. As such, AERMOD is a supplemental analysis intended to address any questions concerning near field impact from primary PM10. See also the Editorial Note at section III.E. Comment No. V.A.4: Regarding other NAAQS: The Bingham Canyon Mine is located in Salt Lake County. The airshed has been designated as nonattainment for PM2.5. DAQ is in the process of developing a SIP for PM2.5. At this time direct source contributions to ambient PM2.5 concentrations are not known. Particulate emissions from the BCM operations settle in the pit and only a very small fraction escape the pit influence boundary into the atmosphere. During inversions, when there are no winds, there have been observed cases of pit settling approaching 100 percent and retention of gaseous pollutants, as well as primary particulates is believed to occur. As the SIP is developed and an attainment strategy is developed, KUC understands that additional controls may be necessary under the SIP. KUC will meet the requirements of the applicable SIP as mandated in Section 110(l) of the CAA, but cannot commit to control strategies that have not yet been developed or shown to be effective. With regard to ozone, a SIP has not been developed for the 8-hour ozone standard so specific control strategies have not been developed. As with PM2.5, KUC will meet the requirements of the applicable SIP. Changes to the BCM emissions profile will be included in the development of the ozone SIP and appropriate control strategies will be implemented when they are developed. In the meantime, KUC and the BCM expansion are in compliance with developed PM10 control strategies and approved regulations. With regard to NO2, the area is expected to be in attainment of the 1-hour standard. At this time, there is no indication that additional control strategies are required to maintain the NAAQS. As previously stated, if future additional control strategies are required to maintain the 1-hour NO2 standard, KUC will implement the applicable requirements (Comment made by KUC). DAQ Response - (see response to Comment II.1) B. 2005 PM10 Maintenance SIP. Comment No. V.B.1: Because the previous UAM modeling files are unavailable, the use of the CALPUFF modeling system combined with the previous UAM modeling was used to evaluate the impact of the increase in material moved at the BCM. This approach was required by DAQ. CALPUFF is a multi-layer, multi-species, non-steady-state Gaussian puff dispersion model that can simulate the effects of time-and space-varying meteorological conditions on pollutant transport, transformation, and removal. CALPUFF can use the 3-dimensional meteorological fields developed by the CALMET model or simple, single station winds. CALPUFF is well suited for this application as it handles very low wind speeds during inversion events and also has the ability to handle complex terrain. The results of the CALPUFF model were added to the predicted UAM concentrations to account for the total impacts after the increase in production (Comment made by KUC). DAQ Response - See Comment No. III.A.2 - Section a). This response addresses the fact that it is not the UAM modeling files that are unavailable from DAQ, but rather the executable code and programs of the UAM-AERO computer model itself that are unavailable. Comment No. V.B.2: EPA has identified several deficiencies in the modeling performed as part of the 2005 Maintenance SIP, specifically the modeling of banked emissions as though they will be emitted from Kennecott's 1,200 foot stack and the reliance on RRFs based only on total mass. The modeling presented in the TSD is consistent with the 2005 Maintenance SIP that has been adopted into State law. It is not an attempt to resolve more fundamental issues that EPA has raised regarding the type of modeling demonstration that will be necessary for EPA to approve a future plan. KUC used the current 2005 UAM modeling and the modeling of the banked emissions as it was completed for the 2005 Maintenance SIP. The RRFs were kept consistent with the state-approved DAQ modeling. The maintenance demonstration approved by the AQB remains valid notwithstanding the proposed increase in material moved (Comment made by KUC). DAQ Response - See response to Comment No. III.A.1. Comment No. V.B.3 - Regarding EPA's assessment that the combination of CALPUFF simulations with UAM-AERO is insufficient and their recommendation that the impacts of the BCM expansion be evaluated using the new CMAQ model simulations currently being developed by the State for the PM2.5 attainment plan, KUC offers the following: The PM10 Maintenance plan was approved by the Utah Air Quality Board in 2005 as a matter of State law. Therefore, DAQ considers the limitations established by the SIP to be enforceable notwithstanding that EPA has yet to take final action on the 2005 Maintenance plan. Accordingly, the material moved limitation must be changed in accordance with state law and in a manner that is consistent with the Board's approval in 2005. It is KUC's understanding that any changes to the BCM operations will be included in the CMAQ model simulations currently being developed by DAQ (Comment made by KUC). DAQ Response - See response to Comment No. III.A.1. DAQ Response - See response to Comment No. III.A.1. C. 1994 PM10 Attainment SIP Comment No. V.C.1: EPA has raised concerns about KUC's proposed use of stacklevel SO2 credits to offset ground level PM10 and NOx emissions at the BCM which lies a considerable distance from the 1,200 foot stack. EPA asserts that additional modeling would be required to show non-interference under the CAA section 110(l), and even raises the question of whether the banked credits are valid. To these concerns, KUC offers the following: KUC says offsets are being provided for the sole purpose of demonstrating that the 1994 attainment demonstration is not adversely affected by the increase in material moved. The offsets being relinquished are entirely consistent with the 1994 PM10 SIP offset provisions. These provisions, as approved by EPA, allow the use of PM10 precursors to offset direct PM10 emissions. KUC also says, the1994 PM10 SIP attainment demonstration was based on receptor modeling which does not specify source emission heights but does include the relative impacts from sources as measured by the ambient air monitors. Therefore, the offsetting program established in the l994 PM10 SIP does not distinguish between release heights. The receptor modeling does account for impacts from the 1,200 foot stack so the impacts from these emissions were included in the attainment demonstration and are creditable. According to KUC, the 1994 federally-approved SIP and 2005 State Maintenance plan requirements have been met. Concerning the validity of the banked credits, KUC has submitted written confirmation to DAQ that the emission reduction credits being relinquished meet the requirements of the offsetting program and are valid offsets. The SO2 credits were generated in 1996 - 1998 during the Smelter modernization project. The Smelter modernization project was completed in 1996 and reduced SO2 emissions by 99.9%. The KUC Smelter continues to be one of the most advanced and cleanest smelters in the world (Comment made by KUC). DAQ Response - DAQ agreed with Kennecott concerning the use of these banked credits, and also pointed out that the elevation of "ground level" at the pit exceeds the elevation at the top of the 1,200 foot stack by at least 800 feet (See also response to Comment No. III.B.i.1.).

Reasoned justification for continuation of the rule, including reasons why the agency disagrees with comments in opposition to the rule, if any:

Clean Air Act Section 110(a)(1) (42 USC 7410(a)(1)) requires that each state adopt and submit to EPA a plan providing for implementation, maintenance, and enforcement of each health standard promulgated by EPA. If a state fails to do so, EPA is to issue a federal implementation plan in its place, and other federal sanctions also would apply. Rule R307-110 incorporates by reference the state implementation plan (SIP) allowed under Subsection 19-2-104(3)(e). Therefore, this rule should be continued.

The full text of this rule may be inspected, during regular business hours, at the Division of Administrative Rules, or at:

Direct questions regarding this rule to:

• Mark Berger at the above address, by phone at 801-536-4000, by FAX at 801-536-0085, or by Internet E-mail at [email protected]

Authorized by:

Bryce Bird, Director

Effective:

02/01/2012