### ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 IEPA-RlO-OAR-2012-0581; A-1-FRLApproval and Promulgation ofAir Quality Implementation Plans; Idaho Amalgamated Sugar CompanyNampa BART Alternative AGENCY: Environmental Protection Agency (EPA). 

### ACTION: Proposed rule. 

### SUMMARY: The Environmental Protection Agency (EPA) is proposingto approve a revised BART determination and an alternate control measure for TheAmalgamated SugarCompany, LLC. (TASCO) plant located inNampa, Canyon County, Idaho, to meet the requirements ofBest Available Retrofit Technology (BART) for regional haze. The EPA previously approved the State's BART detennination for TASCO as meetingthe requirements for theregional haze provisions in the Clean AirAct (CAA) on June 22, 2011. On June 29, 2012, the State ofIdaho submitted revisions to its Regional Haze State Implementation Plan that included a revised BART detennination for the TASCO**t~tcility,** a revised emission limitation for particulatematter (PM), and an alternative control measure torTASCO to replace the Federally approved sulfur dioxide (S02)BART determination. The EPA proposes to vacate thepreviously approved S02 BART determination torTASCO, approve the revised BART detennination, therevised emission limitation, and the alternative control measure at TASCO.



### DATES: Written comments must bereceived on orhef()fc 

### llnsert date 30 days from date of publication in the Federal Register).ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R10-0AR-2012- 0581, byone ofthefollowing methods: A. www.regulations.gov. Follow the on-line instructions for submittingcomments. B. Mail: Steve Body, EPA, Office ofAir, Waste, and Toxics, AWT-107, 1200 Sixth Avenue, Suite 900, Seattle, Washington 9810I C. E-mail: body.steve@epa.gov [or R I0-Public
_Comments@epa.gov] D. Hand Delivery: EPA, Region 10 Mailroom, 9111 Floor, 1200 Sixth Avenue, Seattle, Washington 98101. Attention: Steve Body, OtliceofAirWaste, and Toxics, AWT-107. Such deliveries are only accepted during nonnal hours ofoperation, and special arrangements should bemade for deliveries ofboxed infonnation. Instructions: Direct your comments to Docket ID No. EPA-RlO-OAR-2012-0581. The EPA's policy is that all commentsreceived will be included inthe public docket without change and maybe made available online at www.regulations.gov, including any personal infonnation provided, unless the comment includes infonnation claimed to be Confidential Business Information (CBI) orotherinformation whose disclosure is restricted by statute. Do not submit infonnation that you considerto be CBI orotherwiseprotected through www.regulations.gov or email. The www.regulations.gov Web site is an "anonymous access" system, which means the EPA will not know your identity orcontact information unless you provide it in thebodyofyour comment. Ifyou send an email comment directly to the EPA without goingthrough www.rcgulations.gov, your email address will be automatically captured and included as part of the comment that is placed in thepublic docket and made available on the Internet. Ifyou submit an electronic comment, the EPA recommends that you include your name and other contact information in the body ofyour comment and with any disk or CD-ROM you submit. If

2the EPA cannotread your comment due to technical difficulties and cannot contact you for clarification, the EPA may not be able to consider your comment. Electronic files should avoid the use ofspecial characters, any form ofencryption, and be fi·ee ofanydefects orviruses. Docket: All documents inthe electronic docket are listed in the www.regulations.gov index. Although listed in the index, some information is not publicly available, 

### i.e., CBI orother infonnation whose disclosure is restricted by statute. Certain othermaterial, such as copyrighted material is not placed on the Internet and will bepublicly available onlyin hard copy fom1. Publicly available docket materials are available eitherelectronically in www.regulations.gov or in hard copy during nonnal businesshours at the Office ofAir, Waste and Toxics, EPA Region 

### 10, 1200 Sixth Avenue, Seattle, Washington 

### 98101.

FOR FURTHER INFORMATION CONTACT: Steve Body, 

### (206) 553-0782, orby email at body.steve@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document whenever "we," "us,"or "our" is used, we mean the EPA. Intonnation is organized as follows: Table ofContents: I. Background II. Regional Haze Rule Provisions for BART Alternative Measures III. Idaho's State Implementation Plan (SIP) Revision Submittal IV. The EPA's Evaluation ofSIP Revision Submittal V. The EPA's Proposed Action VI. Statutory and Executive Order Review


### 3

### I. Background In the Clean Air Act (CAA) Amendments of 1977, Congress established a program to protect and improve visibility in the Nation's national parks and wildcmess areas. See CAA section 169A. Congress amended the visibility provisions in the CAA in 1990 to focus attention
on the problem ofregional haze. See CAA section 1698. The EPA promulgated regional haze regulations 

### (RHR) in 1999 to implement sections 169A and 1698 ofthe Act. Theseregulations require slates to develop and implement plans to ensure reasonable progress toward improving visibility in mandatory Class IFederal areas 1

### (Class Iareas). 64 FR 35714 (July 1, 

### 1999); sec also 70 FR 39104 (July 6, 2005) and 71 FR 60612 (October 13, 2006). Regional haze is impairment ofvisual range orcolorization causedby air pollution, principally fine particulate, producedby numerous sources and activities, located across a broad regional area. The sources include but are not limited to, major and minor stationary sources, mobile sources, and area sources including non-anthropogenic sources. These sources and activities may emit tine particles (PM2.5) (e.g., 

### sulfates, nitrates, organic carbon, elemental carbon, and soil dust), and their precursors (e.g., 

### sulfur dioxide (S02), 

### nitrogen oxides (NOx), and in some cases, ammonia and volatile organic compounds). Fine particulate can also cause serious health effects and mortality in humans, and contributes to environmental effects such as acid deposition and eutrophication. Sec 64 FRat 35715.

1 Areas designated as mandatory Class I Federal areas consist ofnational parks exceeding 6000 acres, wilderness areas and national memorial parks exceeding 5000 acres, and all international parks that were in existence on August 7, 1977. 42 U.S.C. 7472(a). In accordance with section 169A ofthe CAA, EPA, in consultation with the Department ofInterior, promulgated a list of 156 areas where visibility is identified as an important value. 44 FR 69122 (November 30, 1979). The extent ofa mandatory Class l area includes subsequent changes in boundaries, such as park expansions. 42 U.S.C. 7472(a). Although states and tribes may designate as Class l additional areas which they consider to have visibility as an important value, the requirements ofthe visibilityprogram set forth in section 169A ofthe CAA apply only to "mandatoryClass I Federal areas." Each mandatory Class l Federal area is the responsibility ofa "Federal Land Manager." 42 U.S.C. 7602(i). When we use the term "Class l area" in this action, we mean a "mandatory Class IFederal area." 4Data from the existing visibility monitoring network, the "Interagency Monitoring of Protected Visual Environments" (IMPROVE) monitoring network, show that visibility impairment causedby air pollution occurs virtually all the time in most national parks and wilderness areas. The average visual range in many Class I areas in the western United States is 100-150 kilometers, or about one-halfto two-thirds the visual range that would exist without manmade airpollution. 2 Visibility impairment also varies day-to-day and by season depending
on variations in meteorology and emission rates. The deciview (dv) is the metric by which visibility is measured in the regional haze program. A change of 1dv is generally considered the change in visual range that the human eye can perceive. The 

### RHR requires each State's regional haze implementation plan to containemission limitations representing BART and schedules for compliance with BARTfor each source subject to BART, unless the State demonstrates that an emissions trading program orother altemative will achieve greaterreasonable progress toward natural visibility conditions. A State may opt to implement orrequire participation in an emission trading program or other alternative measure rather than require sources subject to BARTto install, operate, and maintain BART. On April 16, 2007, Idaho submittedto the EPA for approval new and revisedrules that provide the Idaho Department ofEnvironmental Quality (IDEQ) the regulatory authority to address regional haze and to implement BART (BART Authority rule). The EPA approved these rules onJune 9, 2011. 76 FR 33651. Idaho submitted its Regional Haze State Implementation Plan as meeting the requirements of40 CFR 51.308 to the EPA on October 25, 2010 (2010 

### RH SIP submittal). The 2010 

### RH SIP submittal covers the planning period of2008 through 2018 and, among the otherrequired elements, includes a BART determination for the TASCO facility in Nampa. Idaho. OnJune 22, 2011, the EPA approved the BARTrelated provisions ofIdaho's

2 !d. 5

### 2010 RH SIP submittal, includingthe final BART determination for theTASCO facility3

. 

### 76 FR 36329. That approval incorporated byreference the September 7, 2010, TASCOTier II Operating Pern1it No. T2-2009.0105 (2010 TASCOTier II Operating Pennit) that contained the emission limitations representing BART t(n· TASCO. On November 8, 2012, EPA took tina! action to approve the remaining elements in the Idaho Regional Haze SIP. 77 FR 66929. Thus, Idaho's 2010 RH SIP is fully approved. On June 29,2012, Idaho submitted revisions (2012 RH SIP submittal) to the 2010 RH SIP that includes: arevised NOx BART detern1ination; a more stringentparticulatematter (PM) emission limitation; and an alternative control measureto replace the S02 

### BART determination torTASCO's tossil fuel-tired Riley Boiler. This alternative control measure is also referred to as the BART Alternative. In addition to the new NOx and PM emission limitations on the Riley Boiler, the alternative control measurerelies on control ofNOx emissions from two otherboilers at theTASCO facility in Nampa, that are not BART eligible emissionunits (non-BART boilers). The alternative measure also takes into account emission reductions resulting from the pennanent shutdown ofthree coal tired pulp-dryers. Therevised NOx BARTdetermination,
more stringent PM emission limitation, and the BART Alternative are contained in a revised Tier II Operating Pem1it, T2-2009.0105 issued to TASCO December 23,2011 (2011 TASCOTier II Operating Pennit). As explained below this alternative measure and revised pem1it result in greater reasonable progress toward natural visibility conditions than the improvement expected from the BART detennination previously approved.

II. Regional Haze Rule Provisions for BART Alternative Measures
3 Upon EPA's final action, TASCO tiled a petition for review in the Ninth Circuit Court ofAppeals challenging EPA's approval ofIdaho's BART determination for their Nampa facility. SeeAmalgamatedSugar v. EPA. No. 11-72445 (9th C'ir.) The case is pending before the Ninth Circuit. 6The RHR contains provisions whereby a state may chooseto implement an altcmative
measure as an alternative to BART, ifthe state can demonstratethat the alternative measure achieves greaterreasonable progress toward achieving natural visibility conditions than wouldbe achieved through the installation, operation and maintenance ofBART. Therequirements tor alternative measures arc established at 40 CFR 51.308(e)(2). As explained in the RHR, the state must demonstrate that all necessary emission reductions will take place during the first longterm strategyperiod (i.e., by 2018) and that the emissions reductionsresulting from the alternative
measure will be surplus to thosereductions resulting from measures adopted to meet requirements ofthe CAA as ofthe baseline elate ofthe SIP. The Idaho rules provide IDEQ authority to consider and adopt altemativc measures as an alternative to BART. See IDAPA 58.01.01.668.06.4 The EPA approved this BARTAlternative rule when it approved the Idaho BARTAuthorityrule. 76 FR 33652 (June 9, 2011 ). Sources subject to BARTmustbe in compliance with the BARTemission limitations as
soon as practical but no laterthan 5 years after EPA approves the implementation plan revision. 40 CFR 5l.308(e)(I)(iv). The EPA approval ofIdaho's BART provisions became effective July 22, 2011, thus TASCO must be in compliancewith the BARTrequirements no laterthan July 22, 2016. Underthe BARTAlternative, as specified in the revised pennit, TASCO must comply with the emission limitationsbyJuly 22, 2016, which is well within the first longterm strategy period which ends December, 2018.

4 Specifically the IDEQ BART Altemative rule provides: "BART Aiternative. As an altemative to the installation ofBART for a source or sources, the Department may approve a BART alternative. Ifthe Department approves source grouping as a BART alternative, only sources (including BART-eligible and non-BART eligible sources) causing or contributing to visibility impairment to the same mandatory Class I Federal Area maybe grouped together: a. Ifa source(s) proposes a BARTalternative, the resultant emissions reduction and visibility impacts must be compared with those that would result from the BART options evaluated for the source(s). b. Source(s) proposing a BART altemative must demonstrate that this BART alternative will achieve greaterreasonable progress than would be achieved through the installation and operation ofBART. c. Source(s) proposing a BART altemative shall include in the BART analysis an analysis andjustificationofthe averaging period and method ofevaluating compliance with the proposed emission limitation. IDAPA 5R.O 1.01.668.06." 7Ill. Idaho's SIP Revision Submittal TASCO operates a sugarbeet processing facility in Nampa, Idaho, that includes a fossil fuel tired boiler refeiTed to as the "Riley Boiler". The Riley Boiler is a BARTeligible source and is subject to BART. In the tina! action on the BARTprovisions in the 2010 RH SIP submittal, the EPA approved IDEQ's BART detennination torthe Riley Boiler. 76 FR 36329. The approved BART level technology and emission limitations identified torthe Riley Boiler and contained in the 2010 TASCO Tier II Operating Permit are: PM: 14 pounds perhour (lbs/hr) and requires the emissions to be controlled using a baghouse; S02: 115 lbs/hr and requires the emissionsto be controlled with spray-dry tlue gas desulfurization (spray-dry FGD); and NOx: 186 lbs/hr and requires the NOx emissionsto be controlled using low NOx burners with overtire air (LNB-OFA). Subsequent to the 2010 RH SIP submission and approval, TASCO submitted to IDEQ additional site-specific engineering analyses and a proposal tor an alternative measure to replace the S02 BARTdetermination tor its bcility. Dispersion modeling was conducted to compare the visibility improvement expected from the alternative control measure to visibilityimprovement expected ti·om implementation ofBART. Based on the new intonnation and proposal, IDEQ revised pmiions ofChapter 10 ofthe 20I0 RH SIP and submitted therevisions, along with supportingtechnical documentation, to the EPA. The 2012 RH SIP submittal contains, among other elements, a new NOx BART detennination for the Riley Boiler and the 20I I TASCO Tier II Operating Permit for the Riley Boiler.
8·The2012 RH SIP submittal revises the NOx BARTdetem1ination for the Riley Boiler. The 2010 RH SIP submittal identified low NOx burners (LNB), LNB with overtire air (OFA), and selective catalytic reduction (SCR) as all technically feasible NOx controls for the Riley Boiler. The State evaluated the cost etlectiveness ofeach technology and cletennined that: LNB is cost effective at $921/ton; LNB-OFA is cost effective at $1270/ton with an incremental cost
over LNB at $2431/ton. At that time, the State detennined that SCRhad a cost effectiveness value of$3768/ton and an incremental cost over LNB-OFA of$10,245/ton. In the 2010 RH SIP submittal, Idaho determined that SCR is not cost effectivebased on the incremental cost ofSCR
overthe cost ofLNB-OFA. In the final action on Idaho's 2010 RH SIP submittal, the EPA approved the State's BARTdetermination. As explained, based on additional on-site engineering analysis conducted byTASCO, Idaho subsequently dctennined that neither LNB-OFA nor SCR
are technically feasible at this facility. See 2012 RH SIP submittal, Chapter 10, Section 10.5. ln the detailed engineering analysis conducted tor installation ofLNB-OFA, TASCO detetmined that there is insufficient space in the combustion chamber for LNB-OFA tor adequate combustion and flame management. As also explained, TASCO and the State now consider SCRto betechnically infeasible due to inadequate space between theboiler and bughouse and
concerns about catalyst fouling and erosion. The analysis also determined that installation after the baghouse would not provide adequate exhaust temperature tor SCRto function properly. lei. Thus, the 2012 RH SIP submittal finds that LNBis the only technically feasible NOx control technology tor the Riley Boiler. Regardless ofthe revised detennination ofwhat NOx control is technically feasible for the Riley Boiler, new, more stringent, BART emission limitations t(x NOx were included in the State's revised BART determination and the new, more stringent, NOx and PM emission

9limitations are included in the revised 2011Tier II Operating Permit. See 2012 RH SIP submittal Chapter I0, Section 10.5 Table 3, and 2011 TASCO Tier II OperatingPennit Condition 3.4. The revised NOx BART determination is based on LNBs for NOx control. Therevised NOx BART detennination for the Riley Boiler strengthens the emission limitations from 186 lbs/hrto 147 lbs/hr, and results in a 21% reduction in NOx emissions from the original BART detem1ination torthe Riley Boiler. It also changes the identified control technology tor NOx upon whichthe BART emission limitation is based, from LNB-OFA to LNBs. As explained below, this new BART determination and more stringent emission limitations were used in the demonstration that the BARTAlternative provides for greaterreasonablepro!:,•Tess to achieve natural visibility conditions than BART. The 2012 RH SIP submittal also proposes as a BARTAlternative an alternativemeasure to the S02 BART determination for the Riley Boiler. This alternative measure covers six emission units at the TASCO facility: the Riley Boiler, the Babcock & Wilcox (B&W) Boilers #1 and #2, and the South, Center, and North Pulp dryers. The alternative measurereplaces the spray-dry FGD S02 control on the Riley Boilerwith LNB NOx control on the B&W Boilers #1 & #2 and takes into account the emission reductions resulting from the shutdown ofthethree pulp dryers. Thus, the retrofit ofthe coal-tired low-NOxburners on the B&W Boilers and resulting NOx reductions and credit for the pennanent shutdown ofthe three pulp dryers arc intended to replace the BART S02 emission limitation for the Riley Boiler. The controls for the B&W Boilers #I & #2 and shutdownrequirements torthe South Pulp Dryer in the 2011 TASCO Tier II Operating Permit, (Condition 4.1) will become Federallyenforceable upon final approval ofthis proposal. Thepennanent shutdown ofthe Center and North pulp dryers is Federally enforceable, as required bythe September30, 2002, TASCO Tier II pennit currently in the

10Federally approved SIP. The 2011 TASCO Tier II Operating Permit also includes a revised PM limitation for the Riley Boiler, reducing the PM emission limitation from 14 lbs/hrto 12.4 lbs/hr. The strengthened PM emission limitation results in an II%reduction in PM emissions t!·om the emissions expected th)ln the BART determination previously approved. TASCO conducted air qualitydispersion modeling to estimatevisibility improvement in affected Class I areas in accordance with the three-state, Washington, Idaho, and Oregon BART Modeling Protocol to demonstrate greaterreasonable progress in achievingnatural visibility conditions. This protocol underwent extensivereview and approval and formed the basis for much ofthe BARTmodeling for regional haze conducted in the Pacific Northwest, including modeling in Idaho's 2010 RH SIP submittal. In the 2012 RH SIP submittal, the State demonstrated the visibility improving advantages ofthe BART Alternative by comparingthe visibility improvement ofthe revised BART for the Riley Boiler in the 2012 RH SIP submittal with the improvementresulting from the BART Alternative. Themodel input emissions for S02, NOx and PM were determined for all six emission units included in the alternative measure: the Riley Boiler (S02, NOx, and PM), B&W Boilers #1 and #2 (NOx), and the three coal-tired pulp dryers (S02, NOx and PM). Three scenarios were modeled torall six emission units: baseline (pre-BART), revised BARTtor Riley Boiler, and the BARTAlternative. Emissions from the TASCO facility impairs visibility at seven mandatory Class Iareas within 300 kilometers (km): Eagle Cap Wilderness Area, Oregon; Craters ofthe MoonNational Monument, Idaho; Hells Canyon Wilderness Area, Oregon; Jarbidge Wilderness Area, Nevada; Sawtooth Wilderness Area, Idaho; Selway-Bitteroot Wilderness Area, Idaho; and the Strawberry Wilderness Area, Oregon. Theresults ofthis modeling effort f(w all seven Class Iareas are presented in the 2012 RH SIP submittal, Chapter 10, Section 1 0.5, Table 6. Thedeciview impact

1 1for the 22nd highest day overthe 2003 to 2005 time period is presented for each ofthe seven Class I areas. The submittal shows the number ofdays with impainnent greaterthan 0.5 dv in the 2003 to 2005 timeperiod. TheTablebelow presents the modeled visibility, at all Class I areas within 300 km ofthe TASCO facility at baseline conditions (2003 to 2005), underthe revised BART, and underthe proposed BART Alternative. As shown, theproposed BART Alternative achieves greater reasonable progress toward natural conditions than wouldbe achieved through the installation, operation and maintenance ofBART. Table 1 -Modeled Visibility Conditions

Class I Baseline Visibility Visibility An:a Visibility Impact Impact Impact und.:r under (dvr'·d proposed proposed r<:vised RART BART Alternative (dv)"· d (dv)'· d

- Eagle Cap 2.201 1.512 1.411 Wilderness, OR Craters of () 393 0.2(,7 0 245 the Moon Wikkrness, ID Hells 1.582 1.092 1.059 Canyon Wilderness, ID;OR Jarbidge 0.375 0.256 0.234 Wilderness, NV Sawtooth 0.47 OJI9 0.307 Wilderness. ID Selway- 0.439 0.281 0.29X Bittenuot Wilderness, ID Strawb<:rry 1.462 1.076 0.917 Mountain Wilderness. OR (a) Includes pre-BART emi"ionsofall sources involved in BART and the BART Alternative: Ril<:y Boikr, B&W Boikrs 1&2 and tlu.:.: pulp dryers. (b) Includes all somces involved in BART and the BART Alt.:rnatiw under BART operations: Riley Boiler(LNB + SD-FGD). B&W Boilers Additional Days ahow Days above Visibility 0.5 dv 0.5 dv under Improvement baseline'· Revised with BART BART' Alt.:mative vs revised BART**(dv)<~** 0.101 195 149
0.022 10 4

()(J33 129 S7

0.022 g 5
0.012 IX 6 (0.017) 15 3

0 15') 80 62

12 Days above Decrease in 0.5 dv under days >0.5 dv BART from BART Alt<:rnative'· Alternative vs Revis<:d BART' 126 23
3 I

xo 7

5 ()

-- 6 0
4 (ll

51 III&2, three pulp dryers opemting. (c) Includes all sources involved in RART and the BART Altemativ.: umkr BART Alternative operations: Riky 13oilcr(LNBJ, B&W Boilers I&2 (LNB), three pulp dryers shut down. (d) The22m! highest dv value I(Jr thethree-yl'ar period (2003 2005). (e) Total numberofdays in the three-year period that exceed 0.5 dv.
IV. The EPA's Evaluation ofthe SIP Revision Submittal I. Revised BART Determination f(xthe Riley Boiler Theprovisions of40 CFR 51, Appendix Y, followed by Idaho, set forth the process used to identify control technologies and to considerthe five statutory factors that mustbe evaluated
as part of a BART determination. After site specific consideration ofthe factors, thebest achievable retrofit technology is identified and the BART emission limitation is specified. As discussed previously in this notice, based on a revised analysis conducted and provided byTASCO, Idaho determined that SCR is technically infeasible for the Riley Boiler. This new finding does not affect the State's final BARTdetermination because, as the EPA previously agreed, Idaho's determination found that even ifSCR was technically feasible it was not cost effective and thus, would not qualify as BART. 76 FR 3632. Thus, the 2012 RH SIP submittal determination that SCR is technically infeasible does not change the EPA's previous agreement that SCR is not BART for this facility. The EPA previously approved the NOx BART emission limitation torthe Riley Boiler of 186 lbs/hr, based on LNB-OFA control technology. However, TASCO's further engineering analysis detennined that while there is insufficient space in the combustion chambertor LNB-OFA tor adequate combustion and flame management, LNB alone could achieve greater NOX control than the LNB-OFA control. Accordingly, Idaho revised its NOx BART determination to reflect thetechnology change,
13greater control and tighter emission limitations. The compliancedate ofJuly 22, 2016 remains unchanged. In the 2012 RH SIP submittal, Idaho strengthened the NOx BART emission limitation to 147lhs/hrbased on TASCO's reassessment ofLNB performance for the Riley Boiler. In light of TASCO'srevised analysis that the original BART detennination is not technically feasible and becausethe revised BART determination results in a more stringent NOx BART emission limitation, the EPA isproposingto vacate ouroriginal BART detennination and approve the revised NOx BART detennination and this new limitation for theTASCO facility. The EPA previously approved Idaho's PM BART emission limitation torthe Riley Boiler of 14 lbs/hr, based on baghouse control technology as provided in the 20I0 RH SIP submittal. In the 2012 RH SIP submittal, Idaho strengthened the PM emission limitation to 12.4 lbs/hr, based
on TASCO's analysis oftheperfonnanceofthebaghouse. Therevised PM emission limitation is more stringent than the limitation previously approved and therefore the EPA is proposingto approve this revised PM limitation as a SIP strengtheningmeasure. 2. Alternative to BART torthe TASCO facility The 2012 

### RH SIP submittal includes a proposed alternative measure to the previously approved S02BART determination tor Riley Boiler. This alternative measure is intended to replace the S02 BART emission limitation of 115 lb/hr torthe Riley Boilers with a combined NOx emission limitation onthe B&W Boilers #1 and #2 of

### I03 lbs/hr, and takes into account the emission reductions resulting from the pennanent shutdown ofthree coal-tired pulp dryers. The baseline emissions tor all three pulp dryers are: NOx-191.2 lbs/hr; S02_17.9 lbs/hr; and PM-927 lbs/hr. These emissions were permanently eliminated when the pulp dryers were shutdown.

5 Current statewide regulations limit the sulfur content ofcoal to I'Y., by weight. IDAPA 5R.O 1.0 1.725.04. This limit would not be affected by the action proposed today and the limit remains applicable to the TASCO t:1cility. 14Installation ofLNB control and establishing emission limitations on the B&W Boilers, along with permanentlyeliminatingthe emissions associated with the three pulp dryers, result in
a total reduction in NOx of221 tly, S02 of20.6 t/y, and PM ofI 13 t/y. The B&W Boilers are non-BART units. The pulp dryers were shutdownbecause installation ofa drying process using waste steam ti·om the boilers instead ofthe pulp dryers reduced the fuel demand that resulted in a lower cost operation, eliminatingthe need t(w the pulp dryers. The shutdown ofthe pulp dryers is not required underthe CAA. Thus, these emission reductions maybe considered surplus. The total emissions are reduced under the BART Alternative measure compared to both the original 2010 RH SIP approved BART determination and therevised BARTdetermination in the 2012 RH SIP submittal. As presented in Table I above, dispersion modeling ofvisibilityin all Class I areas within 300km ofthe TASCO h1cility demonstrates there is overall greater progress towards achieving natural conditions under the BARTAlternative. In particular, thereis greaterprogress in the Eagle Cap Wilderness Area (the Class I area most impacted byemissions from the TASCO facility) ofO.l01 dv underthe BART alternative than underthe revised BART determination and in the Strawberry Mountain Wilderness Area of0.159 dv. The20II TASCO Tier II Operating Permit, Pennit Condition 3.3 requires compliance with the BART AlternativebyJuly 22, 2016, the same compliancedate as the approved BART. Additionally, the permit provides that unless LNBs havebeen installed and operating, as required in Pern1it Condition 3.7, on and afterJuly 22, 2016, the Riley Boilermay be tired only using natural gas, and that on, and after July 22, 2016, the Riley Boilermay not be tired with coal until such date that the coal-tired LNBs are installed and operated in accordance with the permit. See 2011 TASCO Tier II Operating Permit, Pennit Condition 3.9. Permit condition 14.9

15ofTASCO'sTier I Operating Permit T1-050020, issued May 23,2006, required the North and Central pulp dryers to be pennanently shut down and Permit Condition 4.1 ofthe 2011 TASCO Tier II Operating Permit, requires the South Pulp Dryerto bepermanently shutdown. Thus, there is no delay in compliance with BART requirements underthe BART Alternative. The 20II TASCO Tier II Operating Pennit contains the emission limitations discussed above. See 2011 TASCO Tier II Operating Permit, Pennit Condition 3.4 and 3.5. Thepermit also contains requirements tor a non-visibility impairing pollutant, specificallycarbon monoxide (CO). Pcnnit Condition 3.12 requires performance testing for CO. The EPA proposes no action
onthis pennit condition, as it docs not pertain to visibility. The second paragraph ofCondition 3.3 ofthe Pennit allows TASCO to submit a request to obtain IDEQ approved alternatives to BART and to revise the Permit and explains that IDEQ will process the request in accordance with its permitting rules. The condition further provides that the request must be submitted in time tor any such revision to the permit and the con·esponding revision to the RH SIP to be approved priorto July 22, 2016. This provision is administrative in nature and addresses the State's procedure tor possible future revisions to the permit. As such it is not necessary orappropriate tor EPA to act on this provision. Nevertheless,
we note that a revision to a Federally approved permit must meet applicable Federal requirements before it could be incorporated into the Federally approved SIP. The EPA cannot·
assure Idaho orTASCO that any submitted BART Alternative measure will be approved until that measure has been thoroughly evaluated bythe EPA as meeting Federal requirements.



### V. The EPA's Proposed Action The EPA is proposingto vacate ourprevious BART determination tortheTASCO

16facility and to approve Idaho's 2012 RH SIP submittal includingthe revised NOx BART determination for the TASCO Riley Boiler and the 20II TASCO Tier II Operating Pennit containingthe BART Alternative conditions 1.2 includingthetable ofRegulated Emission Point Sources Table, 3.2, 3.3 (first parah'Taph only), 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 3.11, 3.13, 3.14, 3.15, 3.16, and 4.1. Specifically, the EPA proposes to approve new BART emission limitations f(Jr NOx, the revised PM emission limitations and the BART Alternative at theTASCO facility because they provide greater overall reasonable proh'Tess toward achieving natural conditions in affected Class I areas than the previously approved BART determination for the TASCO facility.

VII. Statutory and Executive Order Review Under the Clean AirAct, the Administratoris required to approve a SIP submissionthat complies with the provisions oftheAct and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve state choices, provided that theymeetthe criteria ofthe Clean AirAct. Accordingly, this proposed action merely approves state law as meeting Federal requirements and does not impose additional requirements beyond those imposedby state law. For that reason, this proposed action:
• is not a "significant regulatory action" subject to reviewbythe Oftice ofManagement and Budget under Executive Order 12866 (58 FR 51735, October4, 1993);
• does not impose an inf(mnation collection burden underthe provisions ofthe Paperwork Reduction Act (44 U.S.C. 3501 etseq.);
• is certified as not having a significant economic impact on a substantial numberofsmall entities underthe Regulatory FlexibilityAct (5 U.S.C. 601 etseq.);

17• docs not contain a·ny unfunded mandate or significantlyoruniquely affect small governments, as described in the Unfunded Mandates Refonn Act of 1995 (Public Law I04-4);
• does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August I0, 1999);
• is not an economically significant regulatory action based on health or safetyrisks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);
• is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001 );
• is not subject to requirements ofSection 12(d) ofthe National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application ofthose requirements would be inconsistent with the Clean Air Act; and
• docs not provide EPA with the discretionary authority to address, as appropriate, disproportionatehuman health orenvironmental cft'ects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994). In addition, this rule docs not havetribal implications as specifiedby Executive Order 13175 (65 FR 67249, November9, 2000), because the rule neither imposes substantial direct compliance costs on tribal govemments, nor preempts tribal law. Therefore, therequirements ofsection 5(b) and 5(c) ofthe Executive Orderdo not apply to this rule.



### List ofSubjects in 40 CFR Part 52 Environmental protection, Airpollution control, Intergovernmental relations, Nitrogen dioxide, Particulate matter, Reporting and recordkeeping requirements, Sulfur oxides, 18and Visibility.

Dated: 

### _C--J,b:_:_I_Y (,_,_J-=-J
__ 

# R
. "D;t;:l"' \ p 

## A L..'- "' '"' ''

## ~c..'f'""""**~E'"(q \~"-)At_** **~OM.** \"-1

## \~'\~'A\1)~ Region 10.

19