## USDA United States Department of Agriculture, Forest Service Rucky Mountain Region 740 Simmf; Strcnt Golden, CO 80401 Voice: 303-275-5350 TDD: 303-275-5367

David A. Finley Air Quality Administrator Wyoming Department ofEnviromuental Quality 122 West 25th St.

. Cheyenne, WY 82002

These BART determinations are a keypart ofthe regional haze plan the State ofWyoming is preparing. This plan will demonstrate how Wyoming will make reasonable progress toward meeting the national goal ofpreventing any future, and remedying any existing, impairment of visibility in mandatory Class I areas. The regulations describing what these plans should contain are found at 40 CFR 51.300 through 309. As the Federal Land Manager (FLM) for the North Absaroka, Washakie, Teton, Fitzpatrick, Bridger, Savage Run, Mount Zirkel, Rawah, FlatTops, and Eagles Nest Class I Wildernesses, we are very interested in these BART dete=inations and the Wyoming Regional Haze Plan as a whole. The regional haze regulations at 40 CFR 5l.308(i) require consultation between the FLMs and the State. Specifically, the FLM is to receive 60 days to review and comment on any plan or plan revision. The State must also include a description ofhow it addressed the FLM comments ifthey are received in the specified timeframe. As you Imow, the BART determination must consider the "best system ofcontinuous emissions control technology" taking into account the following factors: "the technology available, the costs of compliance, the energy and non air quality environmental impacts of compliance, any pollution cOlltrol equipment in use at the source, the remaining usejUllife of the source, and the degree of improvement in visibility," 40 CFR Section 51.308(e)(I)(ii)(A). Our review ofthe five statutory factors leads us to the conclusion that selective catalytic reduction (SCR) shouldbe BART for nitrogen oxides (NOx) for all units atboth the Jim Bridger and Naughton powerplants. We applaud the State ofWyoming for proposing to install SCR at the 4 units at the Jim BridgerEGD. The FS believes the installation timeframe for SCR should be within the 2015-2016 tirneframe for all four units at the facility.

·It's Cool to Be Safe Printed on Recycled PaperDavid A. Finley, WDEQ

The FS believes that the already-pennitted installation ofwet flue gas desulfurization (FGD) equipment for the Jim Bridger PowerPlant Units 1-4 shouldbe BART. Similarly, the FS believes that the installation ofwet FGD equipment for the Naughton Power Plant Units 1-3 shouldbe BART. 

### 2

HARV FORSGREN Regional Forester Intennountain Region The United States Forest Service compliments you on your hard work and dedication to significant improvement in ournation's air qualityvalues and visibility. Cooperative efforts such as these ensure that, together, we will continue to malce progress toward the Clean Air Act's goal ofnatural visibility conditions at our Class I wilderness areas and parks. We appreciate the opportunity to continue to work closely with your agency as you develop final BART detenninations for these facilities. Ifyou have questions or comments, please contact Jeff Sorkin, at (303)-275-5759. Sincerely,



# .tD**~-IIa_ ~Sr~**  CKD. CABLE "-/ Regional Forester Rocky Mountain Region Enclosures

cc: .JeffA Sorkin, 

### Ann Acheson, TrentR Wickman, Terry Sva1berg, Scott A Copeland, Bruce Polkowsky, Don Shepherd, Dean GillamUnited States Forest Service Technical Comments Wyoming BART determinations for Jim Bridger and Naughton Power Plants The units under consideration are four 530 MW units (numbered 1 through 4) at the Jim Bridger powerplant and 3 units atthe Naughtonpowerplant; 160,210,330 MW respectively for units 1 through 3. " Overall Comments: The FS commends PacifiCorp and the Wyoming DEQ for the strong NOx controls proposed for BART and reasonable progress. We believe the proposed controls will significantly improve air quality in the many Class I areas surrounding the facilities. While we do not agree with every conclusion, tlle BART documents are thorough and well written. Demonstration ofthe Extent ofVisibility Impacts: PacifiCorp modeled visibility improvements from proposed BART andreasonable progress controls. The FS feels it is important to document visibility impacts to Class I areas as completely as possible in order to place in context the total benefit derived from controls. Then, the cost ofeachBART alternative shouldbe dividedby the sum ofthe deciview improvement at all impacted Class I areas to detemrine the cost per deciview. This may result in acceptarlce ofa previously discarded control alternative due to the showing ofareasonable cost ofvisibility improvement. As such, the 'FS would like to see visibilitybenefitmodeling for all Class I areas within 300km. (see maps attached.) Additionally, since there are Class I areasjustbeyond 300km, ifany modeling ah-eady exists showing visibility improvementbenefits greaterthan 0.5dv beyond 300km, the FS requests that informationbe included as welL The State ofWyoming has determined that the Savage Run Wildemess Area will be marlaged as a Class I airshed. Therefore, tlle FS would like the SavageRun Wilderness Area to be treated as suchin all Regional Haze planning including this BART review. Pages ES-5 and 5-10 ofthe PacifiCorp BART Analysis discuss "Just-noticeable difference in atnlospheric haze" indicating that minimal, ifany, observable visibility improvements at the Class I areas wouldbe expected under any ofthe control scemuios. It is incorrect to dismiss a control strategy on the basis that the resulting improvement is notperceptible or significant. EPA states in the preamble to its BART Guidelines: "Even though the visibility improvement ji-om an individual source may not be perceptible, itshouldstill be considered in settingBARTbecause the contribution to haze may be significant relative to othersow'ce contributions in, the Class I areas. Thus, we disagree that the degree ofimpainnentshouldbe contingent uponperceptibility. Failing to consider less-than-perceptible contributions to visibility impairmentwould igiwre the CAA '.I intent to have BARTrequirements apply to sources that contribute to, as well as h · . t,,3 cause, suc zmpamnen. ,Five Factor Analysis for BART Selection: In the BART detennination the State ofWyoming discusses the applicability ofpresumptive BART to units at the JimBridger and Naughton powerplants. EPA's view ofpresumptive limits for 802 andNOx for EGUs are that they are "highly cost effective." EPA goes on to say: "States, as a general matter, must require owners andoperators of greater than 750 MW powerplants to meet these BARTemission limits. We are establishing these r-equirements basedon the consideration of certainfactors discussed below. Although we believe that these requirements are extremely likely to be appropriatefor all greater than 750MrV powerplants subject to BART, a State may establish different requirements if the State

. can demonstrate that an alternative determination isjustified basedon a**con.~ideration** of

thejive statutoryfactors.,,4

. So although the presumptive requirements are "extremely likely to be appropriate" a State can demonstrate otherWise based on the five statutory factors. The FS believes that the 8..c'lalysis of coal composition is not only flawed in its conclusions, more principally, it does not meet the requirement for a demonstration ofwhypresumptive limits cannot be reached. NOx Controls: The FS sees the infonnationpresented as supporting SCR as BART for all units atboth Jim Bridger andNaughton powerplants. The State ofWyoming lists the following reasons for not installing SCR as BART on the 4 units at the Jim Bridgerpower plant and units I and 2 at the Naughton powerplant: 1) "The cost of compliancefor installillg SCR on each unit is significantly higher than LNB with separated OFA." 2) "Combustion control usingLNB with separated OFAdoes not require non-air quality environmental mitigationfor the use of chemical reagents 

### (i. e., ammonia or urea) and there is a minimal energy impact." However, the FS believes SCR is BART for all units atboth facilities. The State ofWyoming appears to concur with this finding because, in the detennination, the State says "The cost effectiveness and incremental cost effectiveness of thefourproposedBARTtechnologiesfor NOx are all reasonable". 

### hl addition, FS is confused as to why Wyoming determines SCR as BART at unit 3 at the Naughton Power Plant at $2830/ton but for unclear reasons not at the other six units with costs from $2258

- 2848/ton. The FS would like to point ont that SCR is a mature tec1mology. We are unaware ofany enviromnental degradation due to aproperly operated SCR. Furthennore, our inspection ofthe cost analysis leads us to believe the energy impact associated with operating SCR is included in the cost analysis, which makes this pointraised by the State moot.FOI·the Jim Bridger PowerPlant units, the State ofWyoming indicates: "The'eumulative 3-year averaged visibility improvement ji-om Post-Control Scenario A across the three Class I areas achievedwith Post-Control Scenario B was 0.627Lldvper unit ji-om Units 1-3 and 0.635Lldv ji-om Unit 4." This statementmakes the case that SCRwould result in a significant improvement in visibility. Each unit by itselfimproves visibilityby an amount that results 

### in "contribution" to visibility impai=ent i.e. it exceeds 0.5 dv. The total benefit ofSCR on the four units**(~2.5dv)** easily exceeds the threshold for "causing" visibility impai=ent, l.Odv. Similarly, for the NaughtonPowerPlant units, the State ofWyoming indicates: "The cumulative 3-year averaged 98thpercentile visibility improvement from PostControl Scenario A across both Class I areas achieved11Jith Post-Control Scenario B was 0.405 Lldvji-om Unit I and 0.506Lldvji-om Unit 2_" Again, the FS sees this fact as making the case that this is a significant improvement in visibility_ Each unitby itselfimproves visibilityby an amount thatresults 

### in, or approaches, a "contribution" to visibility impai=ent. The total impact ofSCR on the two units approaches the threshold for "causing" impairnlent. Regarding SCR in the BARTphase ofthe analysis, Table 7 ofthe Wyoming BART Application Analysis shows a removal efficiency of84.4 percent for LNB/OFA/SCRto reach 0.07 lblMMBtu. PacifiCorp and Wyoming have underestimated the ability ofmodem NOx control systems. SCRhas beenretrofitted to many easternpulverized coal boilers that are now achieving 0.05 lblMMBtu on a 30-dayrolling average basis. It is likely thatmany ofthese EOUs are burning eastern bituminous coals with higher fuel-bound nitrogen than thatburned at the Jim BridgerPower Plant. Because 

### "fUelnitrogen can account for up to 80percent of total NOxfrom coal combustion" it shouldbe easier for PacifiCorp to achieve lower NOx emissions than an BOUburning coal with higher fuel-bound nitrogen. IfSCRis capable ofreducing emissions below PacifiCorp's target, then the amount ofthe reductions and consequent visibility improvements will increase. These greater efficiencies shouldbe factored into the costand visibility analyses. Reasonable Progress Controls: The FS requests clarification as to why units 1 & 2 at the Naughton PowerPlant are not required to install SCR as part ofreasonable progress like the other five units. S02 Controls: The FS believes that the already-pennitted installation ofwetFOD equipment for the Jim Bridger Power Plant Units 1-4 should beconsidered BART. Similarly, the FS believes that theinstallation ofwet FGD equipment for the Naughton PowerPlant Units 1-3 should be considered BART. There appears to be an error in the analysis for unit 3 atNaughton. Theperfo=ance ofthe wet FGD was stated to be 0.10 lb/MMBtu (Table 18) but the cost effectiveness analysis was done based on 0.15lb/MMBtu (Table 24). The costper ton for S02 reduction should be calculated using 0.10 lb/MMBtu, ifthat is the correct value. The FS understands the role ofsection 309 in exempting the State ofWyoming from BART and reasonable progress controls for S02 based on the demonstration in WRAP Techniclll Support Document! that the S02 emissions reductions benefits under section 309 exceed those that would have resulted from BART. Further we understand thatthe State ofWyoming has met it targets under the 309 program. The FS would like to know ifthe controls in place at theNaughton and JimBridgerPower Plants are at least equivalent to the control scenario used in the demonstration report. In otherwords, are the existing S02 controls actually as neededto accomplish the "better than BART" demonstration? The FS also notes that the 309 program sunsets in 2018, and that additional S02 controls maybe appropriate for reasonable progress atthat time. Visibility Impairment: US EPA BART guidelines2 state that 0.5dv "contributes" to impai=ent, and l.Odv "causes" impai=ent. The discussion from Ronald Henry is irrelevant and used in an improper context. References: 1. WRAP Technical Oversight Committee, RegionalTechnical SupportDocument for the Requirements of§309 of the RegionalHaze Rule, 5/2008. 2. 40 CFRPart 51, Appendix Y. U.S. Environmental Protection Agency, "Guidelines for BART Determinations Underthe Regional Haze Rule.", July 6, :;1005, See FRVol 70, No 128, page3916l. 3. See 40 CFRPart 51, Appendix Y. The U.S. Environmental ProtectionAgency finalized it's BART Guidelines on June 15, 2005, andpublished the preamble and final rule text in the Federal Register on July 6, 2005. The rulemaking action added Appendix. Y to Part 51, titled "Guidelines for BART Determinations Underthe Regional Haze Rule." See Preamble, 70FR30129, middle colunm. 4. Federal Register, 7/6/05, p.39131

# Class I Areas within 300km of Jim Bridger PP

• JIm Bridger PP Class I Units 

### CJ NPS 

## III USFS I\WiilI FWS

## Class I Areas within 300km of Naughton PP

:' 0 Naughton Distance J • Naughton PP :' Class I Units NPS USFS FWS