### Additional Regional Haze Questions
September 27, 2006 Revision (Question 20 added since August 3, 2006)

Note: The following are questions EPA has recei ved from various States and Regional Planning Organizations (RPOs) related to the submission of regional haze SIPs under the program described by 40 CFR 51.308. This document provide s guidance to the Stat e air pollution control agencies and the general public on meeting th e regional haze SIP requirements. These requirements can be found in sections 169A and 169B of the Clean Air Act and 40 CFR 51.300-

51.309. This document does not substitute for those provisions, nor is it a regulation itself. Thus, it does not impose binding, enforceable requir ements on any party, nor does it assure that EPA may approve all instances of its applica tion, and thus the guidan ce may not apply to a particular situation based upon the circumstances. The EPA and State decision makers retain the discretion to adopt approaches on a case-by-case basis that differ from this guidance where appropriate. Any decisions by EPA regarding a pa rticular SIP demonstration will only be made based on the statute and applicable regulations , and will only be made following notice and opportunity for public review and comment. Ther efore, interested part ies are free to raise questions and objections about th e appropriateness of the application of this guidance to a particular situation; EPA will, and States shou ld, consider whether or not the recommendations in this guidance are appropriate in that situation. This guidan ce is a living document and may be revised periodically without publ ic notice. The EPA welcomes public comments on this document at any time and will consider those comments in any future revisions of this guidance

document.

BART

1. Should a State promulgate a BART rule? S hould a State's BART rule declare that VOC (and possibly ammonia) is/are not visibility impairing pollutant (s), or can this declaration be part of the SIP narrative?

The regional haze rule (RHR) does not require that States promulgate BART rules. States are, however, required under 40 CFR 51. 230 to show they have the legal authority to carry out the SIP. To the extent a BART rule can aid in this requirement, then it should be considered. A State’s regional haze (RH) SIP submittal must include sourcespecific BART emission limits and compliance schedules for each source subject to BART. See 40 CFR 51.308(e). All regulatory re quirements must be approved into the

SIP.

A State’s BART rule should not declare th at VOCs or ammonia are not visibilityimpairing pollutants unless the State has ev idence that VOCs (or ammonia) from its BART-eligible sources are not significant cont ributors to particle formation. Such a

declaration must be substantiated in the SIP documentation. This declaration may be placed in the SIP narrative, which will be a pproved into the non-regulatory portion of the SIP following an opportunity for public review and comment on the State’s conclusion. Furthermore, we recommend that prior to SIP submittal that collaboration between and among States and RPOs and Federal Land Ma nagers (FLMs) occur such that theEPA Q and A - September 26, 2006 2 application of exemptions or other princi ples used by a State/RPO is done with full knowledge among the affected States/RPOs/FLMs.

2. At sources that require BA RT but that have PTEs of less than 250 TPY for VOCs and ammonia, must the BART proposal anal yze controls for VOCs and ammonia?

States must use their judgment to determ ine whether VOC or ammonia emissions from

individual sources in their State are likely to have an impact on visibility in an area. For a source such as the one you have described, th e State must consider whether its VOC or ammonia emissions are likely to have an impact on visibility at a Clas s I area. If so, the BART proposal must analyze contro ls for such VOCs and/or ammonia.

3. Should a State declare the exemption threshol d value is 0.5 dv (or some other value) in

their rule? EPA has si mply set an upper bound.

The exemption threshold value selected by the State in determining whether a BARTeligible source can reasonably be anticipa ted to cause or contribute to visibility impairment must be specified in the SIP doc umentation, as must the basis for the States’

selection of this threshold. The appropriateness of the thresh old used by the State will be subject to public review and comment, a nd States should consult with the affected States/RPOs/FLMs in establishing this value.

4. How should a State document in the SIP that BART controls will be installed and in operation as expeditiously as practicable, but no later than 5 years after approval of the

SIP? Must BART controls be housed in a Title V permit modification?

As specified in 40 CFR 51.308(e)(1 )(v), States are required to ensure each source subject to BART install and operate BART as expeditiously as practicable , but in no event later than 5 years after approval of the implementation plan revisio n. States should ensure that BART requirements in a SIP are written in a way that clearly sp ecifies the individual emission unit(s) subject to BART regulati on and the time by which the emission unit(s) must begin to comply with the BART limit. Because the BART requirements are ‘‘applicable’’ requirements of the CAA, th ey must be included as title V permit conditions according to the procedures establ ished in 40 CFR part 70 or 40 CFR part 71. Under 70.7(f)(1)(i) Title V permits must be reopened and revised to include new applicable requirements if the permit has three or more years of life. The reopening must be completed within 18 months after promulga tion of the new applicable requirement and the reopening must follow the sa me procedures (public comment , etc) as apply to initial permit issuance. This may require that States provide commitments in the SIPs to ensure that all applicable construction permits under Title 1, and the operating permits under

Title V are revised in time.

The following elements, at a minimum, must be addressed to ensure the BART controls are adopted into the State’s SIP. These el ements are discussed in detail with other circumstances in 40 CFR Part 51, Appendix Y – Section V.EPA Q and A - September 26, 2006 3 • Name of source facility and the specific emission units and pollutants being controlled. (40 CFR 51. 308(e)(1)(i) & (ii)).

• Specifics of the controls, control effici ency(ies), emissions reductions expected

• Enforceable emission limitations repr esenting BART (40 CFR 51.308(d)(3);(e))

• Schedules for compliance with BART (40 CFR 51.308(d)(3);(e))

• A requirement that each source subject to BART maintains the control equipment and establish procedures to ensure su ch equipment is properly operated and maintained. (40 CFR 51.308(e)(v))

• Reporting, monitoring, and recordkeeping re quirements adequate to determine the source’s compliance (40 CFR Part 51, Appendix Y – V).

• Averaging times and reference methods to determine compliance (40 CFR Part 51, Appendix Y – V).

5. In the BART guidelines under st ep 4 of a BART determinati on is a discussion of average cost effectiveness, yet we don't see anything be ing averaged. If one were to average all

the individual annual cost eff ectiveness over the remaining life of a plant, then we could see that we were averaging so mething. Can you explain this?

The term “average cost effectiven ess” is a term that the Agen cy has long used to describe one method of looking at the costs of contro l when considering economic impacts. See e.g. New Source Review Draft Manual (Oct. 199 0) at B. 36 describing the process for making best available control technology dete rminations (BACT). The Appendix at the end of this document contains equations that can be used for determining average cost effectiveness and should help you to understa nd how to estimate the “average cost

effectiveness” of vari ous control measures.

6. Is there a guideline on how to "annualize" co sts (capital recovery factors and levelizing inflation adjusted operation & maintenance costs)?

Yes. The EPA Control Cost Manual , referenced in the fina l BART rule (see 70 FR 39104, 39163-39167 (July 6, 2005). As noted in the Guidelines, the Control Cost

Manual is updated periodically. This document is available at the following Web site: http://www.epa.gov/ttn/catc/products.html

7. In the BART guidelines under step 4 of a BART determin ation, "how do I calculate baseline emissions?" it would help if a me thod were suggested to depict anticipated

annual emissions from the source. Otherwis e, sources will do this in many different ways. Should States suggest facilities us e a method similar to PSD - the highest 12 consecutive months in the past 120 months (or whatever it is for PSD)? If so, should it

be different for EGUs as it is for PSD? Or , should a facility ta ke the highest 24-hour actual rate and multiply it times their average utilization rate for the highest 2 of the past 5 years? In either case, if these cost effectiveness numbers are compared to the BACT/RACT/LAER clearinghouse, it will make a difference.

The BART Guidelines state that the baseline emissions used for estimating the average

cost effectiveness of a cont rol technology should represen t a realistic depiction ofEPA Q and A - September 26, 2006 4 anticipated annual emissions for the s ource. The approach for making BACT determinations in the PSD program is sim ilar. The methodology of looking at the annual average of the highest 24 consecutive months in the past 120 months is one approach that has been used in PSD when determining if there has been an emissions increase as a result of a modification. In some cases, this approach could a reasonable method of estimating anticipated annual emissions for a source.

8. How do you address an issue in which the in stallation of a BART control causes an increase in another pollutant?

In some cases, the installation of controls to reduce emissions of a pollutant can result in collateral increases in another pollutant. Fo r example, the use of low NOx burners can

result in an increase in CO emissions. If the increase in emissions of a collateral pollutant would trigger other requirements unde r the Clean Air Act, such as New Source Review, the State may include th e costs, if any, of controll ing emissions of a collateral pollutant to meet these other requirements in considering the economic impacts of a technology under consideration for BART.

9. How will EPA address the cost effectiveness of control options? If an option reduces more than one pollutant, how is that addressed?

If an option reduces more than one visibility -impairing pollutant, it could be justified in terms of the greater overall emission reduction. The State will need to evaluate the costeffectiveness of controlling both pollutants in light of its evaluation of the other BART factors. In general, the greater the overall emissions from multiple pollutants, the more closely the State should consider controls on multiple pollutants.

10. It is unclear in the responses to the BART Q and A the meaning of some terms. Some appear to be interchangeable. It would be helpful to have definitions for source, site, unit, and plant-wide (as they pertain to BART).

General terms not defined in the BART Gu idelines should be given the same plain language meaning that they have under othe r Clean Air Act programs. Terms which are defined in this and other CAA regulations, and in the statute, should retain those definitions; note however that the “BART-elig ible source” refers only to stationary

sources built within the BART time period (1962-77) comprised of the emissions units meeting all three BART-eligib ility criteria. See 40 CF R 51.301 for definitions of “stationary source” and “BART-eligible source .” “Plantwide” means across the entire geographic entity, or across all “BART-eligible” sources at the geographic entity (depending on the context).

11. In the BART rule, are we to assume that de minimis levels for pollutants are only based on BART-eligible sources, even when the term “plant-wide” is used?

Generally yes. The approach used by EPA in the BART Guidelines for identifying a BART-eligible source begins with the identi fication of those emissions units at a plantEPA Q and A - September 26, 2006 5 that fall within one or more BART categorie s and that were put in to operation within the 1962-1977 timeframe. In 2004, after proposing th at States be allowed to establish de

minimis levels for pollutants at BART-eligi ble sources, EPA received comments suggesting that de minimis levels be applied on a unit by unit basis. EPA rejected this suggestion in the final rule; the regu lations allow States to establish de minimis levels that apply to a BART-eligible source. In light of the comments received requesting that the

de minimis exemption be applied on a unit by unit basis and its decision to reject this approach, EPA made the statement in the BART Guidelines that “[these de minimis levels may only be applied on a plant-wide ba sis.” This statement was intended to clarify

that the State should consider the cumula tive emissions from the units at a plant that comprise the BART-eligible source in determining whether the BART-eligible source meets the de minimis exemption requirements.

Note, however, that for category one (fossil fuel fired steam electric plants >250 million Btu/hour), our interpretation of the source cate gory title is that th e State should add all EGU emissions at a plant together when determ ining plant capacity, in order to see if the plant falls within category one. Once you have determined that the plant does fall within the category, the State would only consid er those EGUs built within the 1962-77 timeframe to actually be BART-eligible.

12. If a State determines that a recent BACT determination on an emission unit is BART,

then is a BART emission limit created that is th e same as the BACT limit, and is the Title V permit changed so that BART is also lis ted as a basis for that emission limit?

Yes, if a State makes such a determinati on and includes it in its SIP, then a BART

emission limit is created that is the same as the BACT limit. The Title V permit must be amended to “specify and reference the origin of and authority for” the emission limit. 40 CFR 70.6(a)(1)(ii).

13. Is EPA presuming a level of control for BART eligible sources in guidance to consider CAIR plus BART plus other "reasonable" measures?

Guidance on the level of BART controls is not being developed. BART can only be determined on a case-by-case-basis and sour ce-by-source-basis usi ng the modeling and statutory factors listed in 40 CFR 51.308(e)(1)(ii)(A). Sour ces have expressed concern that reasonable progress guidance might be in terpreted to override BART guidance. The BART assessment is a separate requirement fr om the reasonable progress test. It may be that to meet reasonable progress, more cont rols are needed from certain sources which may or may not include those sources previ ously controlled under BART. There is no way for EPA or the States to determine the final strategy to comply with the reasonable progress demonstration until the BART assessment is completed and the suite of controls that are needed for RH is determined. There could also be additional controls that may

be identified as needed to demonstrat e compliance for the 8-hour ozone and PM2.5 NAAQS. This may or may not affect the c ontrol identified under BART or CAIR. The States have flexibility in determining the type , pollutants and mix of sources that could beEPA Q and A - September 26, 2006 6 used in developing a strategy for attain ing a NAAQS per the modeling guidance and implementation policy.

14. Can a source avoid BART by taking synthe tic minor limits on the PTE of visibilityimpairing pollutants? If so, by when do those limits need to be in place? What kind of mechanism must be in place to ensure those limits are met? For how long?

Yes, a source can opt to revi se its Title I permit to provide for synthetic minor limits so that it falls under the BART eligibility thresh old. The limitations of a source’s potential to emit should be in place prior to the star t of the State’s public comment period on its proposed Regional Haze SIP to EPA and a de scription of the State’s action should be included in the SIP narrative. To prevent ci rcumvention of the BART requirements, it may be necessary to include a permit term or SIP provision that provid es that changes at the BART-eligible source or in its permit that allow for increases in emissions would subject the source to BART review.

15. If the unit is already controll ed (e.g., under MACT or BACT) a nd it is the best, the latest control technology, does the source still need to conduct a full blown BART analysis and control technology evaluation incl uding the installed control de vice? Or, can the source just describe the control devi ce on their BART-eligible source unit and make the case that it qualifies as BART, without having to evaluate other technologies?

If the unit has “best, latest...”, then the sour ce can just describe the control device on their BART-eligible source un it and make the case that it qualifies as BART, without having to evaluate other technologies. Th e streamlining of BART analyses in this

situation is addressed in S ection IV.C of the BART Gu idelines, “How does a BART review relate to [MACT] Standards unde r CAA section 112, or to other emission limitations required under the CAA?”

16. A source is built prior to 1962. Between 1962 and 1977, it builds a new emission unit that otherwise meets BART eligible require ments. Is the new unit subject to BART?

If a State is following the approach for iden tifying BART-eligible units described in the BART Guidelines, the unit built between 1962 and 1977 is considered to be BARTeligible.

17. Although the rule in the Federal Register (FR), July 6, 2005 page 39107 and elsewhere

indicates that the max 24 hour emissions should be used, would EPA approve using

double the actuals instead fo r CALPUFF BART modeling?

As noted in the final BART rule, emissions from a source can vary widely on a day to day basis and the “24-hour act ual emission rate could be more than double the daily

average. See 70 FR at 39129. We recommend th at States use the highest 24-hour average actual emission rate for the most recent three or fi ve year period of meteorological data in the CALPUFF mode l. As EPA explained, “[t]he emission

estimates used in the models are intended to reflect steady-stat e operating conditionsEPA Q and A - September 26, 2006 7 during periods of high capacity utilization.” Id. Given the potential variability in actual emissions, use of actual emissions (even doubl e actual emissions) does not necessarily represent this.

18. If a State participates fully in CAIR, and sa tisfies its BART obligation for EGUs for NOx and SO2, must the PM BART eligibility analysis consider whether all visibility impairing pollutants, summed across a facility, exceed 250 tpy, or must only the PM emissions be

considered?

If at the final step of id entifying the emission units that constitute a BART-eligible source, the State finds that a potential BART-eligible sour ce has the poten tial to emit 250 tpy of any visibility-impairi ng pollutant, then the source is considered BART-eligible. For example, if a potential BART-eligible so urce has emissions of more than 250 tpy of SO2 and meets the other applicab le requirements, then it may be subject to BART review for its emissions of PM. However, if the source’s emissions of PM 10 are less than 15 typ (assuming the State has established a de minimis level of 15 tpy), then the source’s PM 10 emissions need not be addresse d in a BART determination.

19. An EGU has three boilers: a) coal boiler (5500 mmbtu/hr); an d b) two auxilliary boilers (181.6 mmBtu/hr each). The State has determined the coal boiler to meet the first test for BART-eligibility. Since the two auxilliary boile rs do not appear to fall under any of the 26 BART categories, would they pass the fi rst test for BART-eligibility because they contribute to the "steam electric plant"?

As a general matter, all the emission units, incl uding any auxiliary boilers, at a fossil-fuel fired steam electric plant of more than 250 million BTU/hour h eat input would be considered part of the same stationary sour ce. Under the RH regulations, BART applies to certain existing stationary sources; stati onary sources, in turn, are defined to include “all of the pollutant-emitting activities whic h belong to the same industrial grouping, are located on one or more contiguous or adjacent properties, and are under the control of the same person (or persons under common cont rol).” 50 CFR 51.301. The regulations further provide that “[p]ollutant-emitting activities must be considered part of the same industrial grouping if they belong to the same Major Group (i.e. which have the same two-digit [SIC] code).” For most plants on the BART list, there wi ll be only one 2-digit SIC code that applies to the entire plant. As you have described the source in your question, the auxilliary boilers would fall with in the same 2-digit SIC code as the coal boiler; these units accordingly are part of the same stationa ry source as the coal boiler.

Note, however, that if the auxiliary boilers are only used during star tup, then since we do not model startup conditions, those boilers would not contribute any emissions to the modeled visibility impact from the source; therefore those particular boilers may be exempted.

20. (Revision) Q: Can a State determine that a BA RT-eligible source is not subject to BART if the source’s potential to emit is limite d such that the source meets the applicable model plant criteria? Can a State make the same determination if a BART-eligibleEPA Q and A - September 26, 2006 8 source’s potential to emit is limited such th at based on air quality modeling, the source’s predicted impacts on any Class I area are le ss than 0.5 dv above natu ral background? If the answer to these questions is yes, can a State limit a source’s emissions through the following methods:

(a) Requiring installation of a control device. A change in the maximum actual emissions may occur as a result of additional contro ls or from changes in work practice (e.g., operational hours) that limit th e total annual emissions. Where emissions controls are installed and operational by December 2007, reduc tions will be achieved earlier than the

BART control deadline of 2013 a nd reductions will be certain. (b) Changing permitted potential emissions . A permit change without a change in

maximum actual emissions would mean that a BART-eligible source is willing to take a federally enforceable permit limit that rest ricts them from emitting above a certain amount. This type of change would only be made in cases where the existing potential emissions are clearly not reflective of actua l maximum emissions and the state permitting authority is assured that the new, lower pe rmit limit is achievable and enforceable.

A: Yes, a State can determine that a BART-elig ible source is not subject to BART if the source’s potential to emit is limited such that the source meets the applicable model plant criteria as described below. For example, a State that has selected 0.5 dv as its contribution threshold, (see 70 FR 39163, July 6, 2005) and is using EPA’s model plant analyses, could exempt a BART-eligible sour ce from BART if the source’s potential to emit is less than 500 tons per year of SO2 and/or NOx, and the plant is located at a

distance from a Class I area of at least 50 km. If a change in emissions is required to meet the model plant criteria, either of the me thods described in Q(a) and Q(b) to limit a source’s potential to emit would be appropriate. The limitations of a source’s potential to emit should be in place prior to the start of the State’s public comment period on its proposed Regional Haze SIP to EPA and a de scription of the State’s action should be included in the SIP narrative. To prevent ci rcumvention of the BART requirements, it may be necessary to include a permit term or SIP provision that provid es that changes at the BART-eligible source or in its permit that allow for increases in emissions would subject the source to BART review.

Similar to the approach described in the preceding paragraph, a State may allow a BARTeligible source to reduce its emissions such that individual sour ce dispersion modeling shows the source’s impact falls below the cont ribution threshold established by the State. As discussed in the BART Guidelines, wh en modeling a source’s predicted impacts on visibility, States should use emissions es timates that reflect steady-state operating conditions during periods of high capacity utiliz ation. As a result, EPA recommends that States use the 24-hour average actual emissi on rate from the highest emitting day of the meteorological period modeled. In cases wh ere the State has limited information on the source’s potential to emit, the State will n eed to develop a reliable and technically supportable estimate of the source’s highest future 24-hour actual em ission rate based on its allowable emission rate, or use the new potential to emit limit for the modeling. As with the case above, the mechanism containing these enforceable limits would need to beEPA Q and A - September 26, 2006 9 in place prior to the date that the Regiona l Haze SIP is submitted to EPA, and other measures may be necessary to avoid ci rcumvention of the BART requirement.

Please remember that States must provide an explanation for selecti on of the contribution threshold, whether it is 0.5 dv or some othe r threshold. As desc ribed in the BART Guidelines contained in 40 CFR Part 51, Appe ndix Y, consideration for establishing the

threshold should include the number of emissi on sources affecting the Class I areas at issue, the magnitude of the sources’ impacts, and the location of the sources. (See 70 FR 39161-39162, July 6, 2005.)

Reasonable Progress

1. Is there a metric for determining if contro ls required for PM2.5, O3, CAIR, or BART are

"reasonable" without defini ng benefit of controls?

Unlike the technical demons tration for CAIR or BART, the reasonable progress demonstration involves a test of a strategy. Th e strategy includes a suite of controls that has been identified through the identifica tion of pollutants and source categories of pollutants for visibility impairment - the po ssible controls for thes e pollutants (and their precursors) and source categories - the application of four st atutory factors and how much progress is made with a potenti al strategy with respect to th e glide path. Modeling occurs with a strategy and is not a source-specifi c demonstration like the BART assessment.

2. How can States demonstrate benefits of c ontrols from a single source for RH without doing single source impact modeling, e.g. CALPUFF?

Reasonable progress is not required to be demonstrated on a sour ce-by-source basis. It is demonstrated based on a control strategy develope d from a suite of controls that has been assessed with the four statutory factors and the uniform rate of progress.

3. What if a State is on the glidepath, but can still install cost effective controls? Is it obligated to install those controls?

From the preamble to the Regional Haze Rule (64 FR 35732), EPA explained:

“If the State determines that th e amount of pr ogress identified through the analysis is reasonable based upon the statutory factors, the State should identify this amount of progress as its reasonable progress goal for the first long-te rm strategy, unless it determines that additional progress beyond this amount is also reasonable. If

the State determines that additi onal progress is reasonable based on the statutory factors, the Stat e should adopt that amount of progress as its goal for the first long-term strategy.EPA Q and A - September 26, 2006 10 The statutory factors must be applied be fore determining whether given emission reduction measures are reasonable. For exampl e, even if emissions reductions from one source category are projected to be enough to achieve the uniform rate of progress towards natural background in 60 years, Stat es should not forego an analysis of what degradation is being caused by pollutants from other source categories, or what improvements could be made by controlling them.

4. A. What type of demonstration is accepta ble to justify a reasona ble progress goal (RPG) that is less than the glidepath? B. What if controls needed for other programs (e.g., PM2.5, ozone, CAIR) are installed?

A. If after applying the four statutory reasona ble progress factors, th e rate of visibility improvement is still less than the uniform glide path, States may adopt the calculated RPGs, provided that they expl ain in the SIP how achieving th e uniform glide path is not reasonable based on the application of the f actors. States must demonstrate why the slower rate is reasonable, and state the projected date for achieving natural background

under this alternative ra te of progress.

B. Existing controls that are installed as a result of other existing CAA programs can contribute to a State’s ability to satisfy its RP G. However, the statutory factors must be applied before determining whether given em ission reduction measur es are reasonable. In particular, the State should adopt a rate of progress greater than the glidepath if this is found to be reasonable according to the statutor y factors. See in pa rticular the directive in the preamble to the RHR at 64 FR 35732.

5. Can a source commit to extra control of one visibility-impairing pollutant in exchange for doing less to control a less significant pollutant (inter-pollutant trading)?

The regulations require the States to adopt m easures that will make reasonable progress toward the national goal. States have the flexibility in developing these measures to focus on those pollutants that have the most significant impact on visibility. A State could conclude that after appli cation of the four statutory reas onable progress factors, it is

“reasonable” to control one pollutant to a higher level than another pollutant.

In the context of BART, the RHR does not pr ovide for inter-pollutant trading where the source is installing controls based on the St ate’s BART determination. The regulations, however, do allow States to adopt alternative measures in lieu of BART, so long as the alternative measures provides for greater re asonable progress than would BART. Interpollutant trading is not allowed in a trading program alternative to BART, -- see 64 FR at

35743.

In addition, States may allow sources to “av erage” emissions across any set of BARTeligible emission units within a fenceline, so long as the emission reductions from each pollutant being controlled for BART would be equal to thos e reductions that would be obtained by simply controlling each of the BA RT-eligible units that constitute BARTeligible source (70 FR 39172).EPA Q and A - September 26, 2006 11 Coordination with RPOs, States, and FLMs

1. What are EPA's expectations and the basi s for consultation requirements regarding formal consultative procedures? What constitutes effective FLM communication? Can it

be assumed that if the FLM attends the RP O meetings and calls and doesn’t raise any concerns it has no problems with a State’s SIP?

40 CFR 51.308(i) requires that States consult with FLMs before adopting and submitting their RH SIPs. These requirements are summarized as follows:

States must provide the FLM an opportuni ty for consultation, in person and at least 60 days prior to holdi ng any public hearing on the SI P. The State must also provide the opportunity for the FLMs to discuss their: (i) assessment of impairment of visibility in any Class I area; and, (ii) recommendations on the development of the RPG and on the development and implementation of strategies to address visibility impairment . Further, the State must include in the SIP a description of how it addressed any comments provided by the FLMs. Lastly, the SIP must provide procedures for continuing consultation between the State and FLMs on the implementation of 51.308, including development and review of SIP revisions and 5-year progr ess reports, and on the implementation of other programs having the potential to cont ribute to impairment of visibility in

Class I areas.

This is a formal consultative process. The basis for requiring written consultation procedures is 40 CFR 51.308(i)(4). To satisfy this requirement, States should contact the FLMs to ensure their input to the RH SIP process is solicited and documented. While effective FLM consultation relies on both pa rties (States and FLMs) communicating early and often, the State is only re quired to meet the provisions of 40 CFR 51.308(i) and is not responsible if a FLM chooses not to participat e in the either the RP O activities or the SIP development and review process. In such cases, the State should document its outreach

efforts to the FLM.

2. Is there a protocol for resolving disputes between States and RPOs regarding technical differences between upwind and downwind St ates on EI, modeling, natural background, apportionment, controls, etc.? How will EP A address States/RPOs adopting different IMPROVE algorithms (old vs. new) to look at the same Class I area?

EPA is developing a State and Federal Prot ocol which will desc ribe the goals and objectives, consultation requirements, prin ciples of collaboration, and process for collaboration for the RH process. While co nceptual in nature, this document will be designed to form the basis for a co mmon understanding, approach, process and expectations for consultation and consistenc y in developing the 308 Regional Haze SIPs. EPA is encouraging the early identification of any potential disputes. This will allow all parties ample opportunity to addres s and document any disagreements.EPA Q and A - September 26, 2006 12 3. We understand that EPA is requiring each Stat e with a Class I area to submit a SIP that addresses its obligations relative to that Cla ss I area including estab lishment of a uniform rate of progress, imposition of requirements to install controls on sources in that State that are considered reasonable, documentati on of its collaborative efforts with other States impacting that Class I area, and also documentation of interactions with surrounding States regarding that State’s contributions to Class I areas in other States. The question is, “When is a State no longer ob ligated to consult w ith another State?”

States are required under 40 CF R 51.308(d)(3), to collaborate and develop coordinated emission management strategies to address RH visibility impairment not only for Class I areas within their own borders, but also fo r each Class I areas located outside their borders which may be affected by their emissi ons. The obligation for States to consult with each other ultimately remains in place for the period of time covered by 40 CFR 51.308. In practice, States will satisfy this obligation mainly during the preparation of the RH SIPs for the first planning period ( 2018), due by 12/17/07, and in the preparation of the ten-year periodic revi sions, and the five-year periodi c reports described in 40 CFR 51.308(f) and (g), respectively.

4. A. Does a State have obligations under the RHR for reasonable progress to initiate

discussions with another Stat e whose sources impact one of its Class I areas if the projected interim visibility improvement in 2018 falls directly on the uniform rate of progress line for that area? Or can the Stat e focus on defining reas onable progress for its sources without engaging other States with contributing sources in discussions?

B. Conversely, do States have obligations under the RHR to evaluate whether their sources are contributing to Class I areas in surrounding States ev en though the Class I areas surrounding it are achieving the uniform rate of progress?

A. Yes, a State must consult with States having sources reasonably anticipated to cause or contribute to visibility impairment in a Cl ass I area to develop their RPGs pursuant to 40 CFR 51.308(d)(1)(iv) regardle ss of the uniform rate of progress for an area.

B. Yes, States must evaluate whether thei r sources are contributing to Class I areas in surrounding States even though th e Class I areas surrounding it are achieving the uniform rate of progress as noted in answer 4. A. Note also that 40 CFR 51.308(d)(3)(i) specifically requires that States with emi ssions that are reasonably anticipated to contribute to visibility impairme nt in another State’s Class I area consult with that State to develop coordinated emi ssion management strategies.

5. For Class I areas that span two or more St ates, is there a requirement for establishing a

“lead” State?

There is no requirement in the RH regulati ons nor in guidance documents to identify a

“lead” State for shared Class I areas. Howe ver, states may choose to establish a “lead”

state if it facilitates their co llaboration and consultation. The RH rule relies on States collaborating and using the cons ultation process (RPOs) to address shared Class I areas.EPA Q and A - September 26, 2006 13 Also, we assume the technical work that is used as the basis would be the same for all SIPs. One may also want to take a look at where the IMPROVE monitor is located that "represents" the Class I area in question, as that location may also help define the "lead" State. Another option is the St ate with the largest portion of the Class I area in their State

to be the “lead” State. These are ideas that could be used, but it is up to the States to work this out as part of the collaborati on and consultation process. We view shared Class I areas similar to interstate NAAQS nonattainment areas. The States involved would collaborate to set one RPG for the area, and work together to define a consistent, coordinated approach to devel op the long-term strategy for the area. As with interstate NAAQS nonattainment areas, each State has le ad responsibility for developing, adopting and submitting its own SIP revisions affecti ng their portion of the Class I area.

6. What if one State with the Class I area sets an RP goal that requires an upwind State to

make reductions that it won't make?

If a State with a Class I area determines that a contributing State is not doing what is reasonable to meet the RPG set for the area, and has attempted to resolve this issue, the State with the Class I area should notify EPA and document this issue in its initial RH

SIP. For all revisions to the initial RH SIP revision, 40 CFR 51.308(h)(2) requires that the State with the Class I area provide notific ation to EPA and to the other States which participated in the regional planning process. This subsection further requires the State

with the Class I area to collaborate with thos e States in the regional planning process to develop additional strategies. It is EPA’s expectation that issues of communication/collaboration problems such as this be brought to our at tention as early in the process as possible.

7. If State A is at or below the glide path fo r an area, and a neighboring State (State B) impacting State A's Class I area does not do al l it can to meet that area's RPGs, what happens? Is State A responsible to file a 126 petition or other action? Could State A's Regional Haze SIP be disapproved because of State B? Are the answers to these questions any different if State A's RPG is above the glide path? In summary, if

consultation does not work what ha ppens and who is responsible?

State A is responsible for establishing RPGs for its Class I areas based on its

consideration of the factors set forth in the statute and implementing regulations, in

consultation with State B and ot her States that may be cont ributing to impairment in the area. See 40 CFR 51.308(d)(1). Each State, including State B, is required to submit a SIP with a long-term strategy that includes m easures as necessary to achieve the RPGs

established for the Class I areas. Where States have participated in a regional planning process, the State must ensure that its SIP includes all measures needed to achieve its share of emissions reductions agreed upon th rough that process. If there is a disagreement among States as to what cons titutes reasonable progress, the question of

whether State A’s or State B’s RH SIP coul d be disapproved will depend on the specific

of the situation. Each State is also res ponsible for documenting its good faith attempt to consult with State B, as outlined in 40 CFR 51.308(d)(1)(iv). EPA will take this information into account in determining whether the State’s goal for visibilityEPA Q and A - September 26, 2006 14 improvement provides for reasonable progre ss towards natural visibility conditions. States are under no obligation to file petitions under Sect ion 126 of the CAA to satisfy the reasonable progress requirement under the RH program.

8. What is necessary in a SIP/template to demonstrate “continuing consultation” under 51.308(i)(4)?

Most States are currently cons ulting with other States and with the FLMs by participating in an RPO. EPA anticipates that most Stat es will address their future FLM consultation requirements by continuing to participate in an RPO that is engaged in an ongoing assessment of visibility issues. If a State de monstrates that it has met current consultation requirements through participation in an RP O that is engaging in the necessary consultations, and if the State intends to sa tisfy future consultation requirements (for periodic comprehensive SIP revisions or for other issues that arise) by continued participation in their RPO, then such a Stat e need only commit to such participation.

For a State that has not fully engaged in the RPO process, the State must provide a description of the process by which it intends to consult with the FLMs in preparing future submittals and addressing issues that aris e. Similarly, if a State has participated in an RPO but intends to discontinue this par ticipation, the State must provide extensive description of the a lternative means by which the State will engage in the required

consultations.

9. To what extent does EPA expect RPOs to motivate States to communicate directly with and engage the FLMs, particularly for Cla ss I areas where those FLMs have not been participating in the RPO's work?

EPA expects that the RPOs will serve as the coordinating entities to facilitate State-toState and State-FLM consultation. To th at end, EPA recommends that RPOs individually set up a formal process to encourage State-to-State and State-FLM consultation to take place, perhaps in th e form of a coordinating workgroup. Through managing this process, RPO’s can help identi fy areas where more FLM participation may be needed. However, RPO’s are not responsible if a FLM opts not to participate in these consultation opportunities. Ultimately, it is th e State’s responsibility to ensure the FLM consultation requirements housed in 40 CFR 51.308(i) are satisfied.

10. What are EPA's expectations of an RPO for written consultation procedures with the other RPOs/States outside its jurisdiction? Given limited funds and much technical and policy work needed, it is suggested this be made as simple and straightforward as possible.

EPA expects that RPOs will serve as the faci litating entities for State-to-State resolution of issues relating to State appor tionment of visibility impairment at Class I areas. RPOs

should also assist States in the resolution of disputes over the levels of control required by upwind States that contribute to visibili ty impairment of downwind States’ Class I areas. This process should begin by each RPO identifying Class I areas for which theirEPA Q and A - September 26, 2006 15 member States individually cause or contribute to visibility impairment. Following this,

the RPOs should meet to broker consensu s between the States on the technical approaches to these issues.

There is no requirement for an RPO to estab lish written consultation procedures with the

other RPOs/States outside its jurisdiction. EPA expects RPOs to facilitate and/or establish procedures in any form at (informal or formal) as needed that works best for the parties involved.

11. Does section 169A(c)(3) of the CAA require a State to obtain FLM concurrence with a State’s proposal to exempt sources from bei ng subject to BART in its Regional Haze SIP

submitted to EPA?

No. The CAA requires States to make BART determinations for BART-eligible sources that may reasonably be anticipated to cause or contribute to any impairment of visibility

in a Class I area. In the BA RT Guidelines, we provides States with an approach for exempting potential BART sources from BA RT by demonstrating that a source does not meet this threshold. In contrast, under sec tion 169A(c)(1) of the CAA, the Administrator has the authority to exempt most sources from BART if he determines that the source is not reasonably anticipated to cause or contribute to significant impairment of visibility. Section 169A(c)(2) contains a similar provision for certain powerplants. The exemptions under section 169A(c), however, are effective only on concurrence by the FLM. In sum, while States must consult with FLMs as part of the SIP process, they are not required to

obtain FLM concurrence with their determina tion that a BART-eligible source does not

cause or contribute to any impairment.

Miscellaneous

1. On December 20, 2005, the IMPROVE Steer ing Committee approved a new algorithm for calculating current and natural background visi bility. If states use the new equation in BART and reasonable progress analyses, will EPA accept it?

Yes, either the new IMPROVE extinction equation as recommended in 2005 by the IMPROVE Steering Committee or the origin al equation recommended by EPA in the "Guidance for Estimating Natural Visibility Conditions Under the Regional Haze Rule" (September 2003, EOA-454/B-03-005) may be used to develop Regional Haze SIPs. Regardless of which algorithm is used for a Class I area, that methodology should be applied in a consistent manner. Consistenc y should be maintained across Regional Haze applications (i.e., BART and Reasonable Progr ess), across time (e.g., baseline and future

calculation for natural conditions ), and among the stakeholders involved who need to be consulted on the development of a LTS for a Class I Area (i.e., FLMs, states, industry). Specifically, we recommend that the same ve rsion of the IMPROVE equation be used by States/sources which are impacting the same Cl ass I area to calculate visibility conditions

for that area.EPA Q and A - September 26, 2006 16 The current CALPUFF modeling system uses an approach that is similar to the original IMPROVE equation. Therefore, a method to appl y the new equation with this model for a BART assessment is needed. Consultation with the EPA Regional Office and FLMs on proposals to use the new IMPROVE equation with CALPUFF for a BART assessment is recommended prior to its use in the modeling.

2. Instead of a single value, can the RPG be sa tisfied using a natural conditions range that captures the variability in year-y ear emissions of natural events?

The 1999 RHR states that in comparing “curren t conditions” against “n atural conditions,” natural conditions means “[t]he level of visibility (in decivi ews) for the 20 percent mostimpaired days, and for the 20 percent least-impa ired days, that would exist if there were no manmade impairment.” 64 FR at 35730. EP A issued a guidance document concerning this entitled, “Guidance for Estimating Natural Visibility Conditions Under the Regional Haze Rule.” Under this guidan ce, a single value for natural vi sibility for each class I areais calculated for each of the 20 percent most-impaired days and the 20 percent leastimpaired days. This guidance document descri bes “default” and “refined” approaches for estimating natural conditions. The EPA methodo logy that allows for the 20% best days and 20% worst days to calculate natural a nd background levels is designed to avoid a single value (i.e., the single best day or the single worst day). The single value that represents the 20% best days is considered representative of the range. Consequently, it would be redundant and unnecessary to further consider ranges of visibility values in determining natural and background levels.

3. What obligation does a downwind State have if it conducts modeling based on an upwind State’s emission inventory, and the upwind States subsequently changes its inventory? What is EPA’s expectation here?

EPA expects that States will continue to work together in addressing the problem of RH,

both inside and outside the RPO context and th at States will share pertinent aspects of their SIP planning with other States, as appropr iate. Upwind States should use their best efforts to provide potentially relevant in formation, such as changes in emissions inventories, to downwind States in timely fashion. We are relying on the RPOs, in large part, to ensure this coordination takes place.

The Regional Haze Rule does not establish a deadline by which States should finalize their emission inventories for purposes of SI P planning. EPA recogni zes that addressing visibility impairment is an ite rative effort and that States will not al ways be capable of incorporating the most up-to-date information in their analyses for the SIPs due in 2007.

If there is a lack of coordina tion on this issue that affects the integrity of a particular State’s SIP, EPA will examine it on a case- by-case basis and take into account the specifics of the situation in its review of the SIP.

4. How does the CAIR substitute for BART?EPA Q and A - September 26, 2006 17 States subject to and participating in the CAIR cap and trade program for SO2 and NOx may treat the CAIR requirements for EGUs as a substitute for the application of BART controls for these pollutants. States do not need to require BART-eligible EGUs subject to the CAIR to install, maintain, a nd operate BART per 40 CFR 51.308(e)(4).

In addition, a State which is only subject to CAIR for NOx, but which also chooses to participate in the CAIR trad ing program for both SO2 and NOx, may consider BART to

be satisfied for both SO2 and NOx from EGUs . Because EPA modeled these States as controlling for both SO2 and NOx in the CAIR NFR, the better than BART demonstration presented in that action would be valid in that scenario. Conversely, if such States choose to participate only in the ozone season NOx trading program, the updated projections presented in the BART ru le (70 FR 39104) demonstrate that BART would be satisfied for NOx, but such States would still need to address BART for SO2 emissions from EGUs (70 FR 39143).

Also, EPA’s assessment that the CAIR cap a nd trade programs can substitute for BART

controls does not extend to cases where a St ate has identified source-specific BART requirements as a result of a reasonable attribution determin ation. In such cases, the source-specific BART requirements must be met at the source.

Finally, the CAIR does not address other pote ntial visibility impairing pollutants such as PM, VOCs, and ammonia. Also, the dete rmination that the CAIR makes greater reasonable progress than BART for EGUs is not a determination that the CAIR satisfies all reasonable progress requirement s in CAIR affected States.

5. If a CAIR facility is found to be exempt from BART for SO2 and NOx, and the State does exemption modeling on PM10 and concludes there is no impact on a Class I area, can the State totally exempt the utility from BART?

States subject to and participating in the CAIR cap and trade program for SO2 and NOx are allowed to treat the CAIR requirements for EGUs as a substitute for the application of BART controls per 40 CFR 51.308(e)(4). This does not mean EGUs are exempt for SO2 and NOx, only that CAIR satisfies the BART requirement for those pollutants.

The remaining visibility pollutants to consid er for determining BART-eligible sources are PM, and, using judgment, VOCs, and ammonia. For PM, the July 6, 2005, final BART rule at 70 FR 39160 notes PM10 may be used an indicator for PM in this step of the determination and thus, PM10 can be used for the exemption modeling.

6. What is the relationship of CAIR to reasona ble progress? Does CAIR satisfy reasonable progress requirements for EGUs for NOx and SO2?

As discussed in the answer to the previous question, participa tion in the CAIR can substitute for a State’s BART obligation in ce rtain narrowly defined areas. However, for the purpose of satisfying the RPG, CAIR has no more applicability than does BART – it is a control that can be part of a State’ s RPG. The preamble to the 2005 BART RuleEPA Q and A - September 26, 2006 18 states that EPA’s determination that partic ipation in the CAIR trading program would provide for greater reasonable progress fr om EGUs than would BART “is not a

determination that CAIR satisfies all reasona ble progress requirements in CAIR affected States.” (70 FR 39143). In other words, a lthough EPA has determined that the CAIR trading program would provi de greater reasonable progress than source specific BART controls for affected EGUs for SO2 and NOx, a State’s reasonable progress analyses may indicate that additional controls beyond CAIR may be necessary to meet the RPGs set for

one or more the Class I areas.

7. What is the relationship of RH BART to RAVI BART?

RAVI BART (Part I of the visibility program ) is a separate regulatory requirement from RH BART (Part II of the visibility program). RAVI BART treats visibility impacts from one source or a small group of sources, as opposed to RH BART, which treats visibility impacts over a wide geographic area. EPA promulgated regulations addressing “reasonably attributable visibility im pairment” or RAVI in 1980. Under these regulations, the requirement for a BART anal ysis is triggered where the FLM certifies there exists reasonable attributable impairment of visibility. You may find this document a useful guide to understandi ng the RAVI process: http://www.wrapair.org/forums/mtf/docum ents/ravi_bart/Final_RA_BART_Report.pdf

Once a State has met the requirements in the RH regulations for BART or implemented an alternative measure, then the BART requi rements of the Act have been met and BART sources will be subject to re gulation under the RH program in the same manner as other sources. 40 CFR 51.308(e)(3). Therefore, ev en though a State may satisfy BART via a 308 SIP, an FLM may still certify RAVI, thus triggering a RAVI BART attribution

determination.

8. What happens if RH SIPs are late?

Section 110(m) of the CAA provides discretiona ry authority for EPA to impose sanctions for failure to submit a required plan.

9. What is EPA's position on the need to treat VOCs and ammonia as visibility-impairing pollutants? If a State wishes to address VOCs and/or ammonia as visibility impairing pollutants, what tools are available to do this?

The BART Guidelines direct that States should look at SO2, NOx, and direct PM emissions in determining whether sources caus e or contribute to vi sibility impairment, including both PM10 and PM2.5. As stated in the BART Guidelines (70 FR 39160),

“States should exercise their judgment in deciding whether [VOCs or ammonia] impair visibility in an area ... a nd in deciding whether VOCs or ammonia emissions from a source are likely to have an impact on visibili ty in an area.” A formal showing of an

individual decision that a s ource of VOC or ammonia emissi ons is not subject to BART review is not necessary.EPA Q and A - September 26, 2006 19 10. 51.308(d)(3)(v)(B) requires that the State, in developing its LTS, consider measures to mitigate the impacts of construction ac tivities. What should this include?

States should include constructi on activities in their emission inventories that are used for long-term strategy development. When EP A promulgated the RHR in 1999, emissions from construction activities, such as emissions from non-road diesel equipment, and large scale wind-blown dust from rapidly growi ng areas like Las Vegas and Phoenix, were a major concern. Subsequently, EPA has pr omulgated rules for on-road and non-road heavy duty diesel engines. St ates should include the emission reductions from those rules in their SIP planning. If St ates have areas where wind bl own dust from human activities

contributes to a reduction in vi sibility at Class I areas, they should consider measures to mitigate this source of visibility-impairment. The Western Regional Air Partnership (WRAP) has a number of products related to dus t that can be downloaded from their site

at: http://www.wrapair.org

11. What is EPA's expectation for filling missi ng data in the IMPROVE record? How many years are required to determine the baseline visibility if data is missing in the 2000-2004 record? Are 3 years sufficient (IMPROVE expe ctation)? Need to create 5 years ?

The "Guidance for Tracking Progress Under the Regional haze Rule" addresses this question in several areas. Five (5) year s of data from the 2000-2004 period should be used. However, because of the deployment of monitors this length of data may not be

available for all Class I areas. The Tracki ng guidance recognizes this and recommends that a minimum of three years of data shoul d be used if more years do not exist (see pages 1-4, and 2-8).

All five years should be used if available a nd suitable per guidance recommendations. If not, then a minimum of three years is reco mmended. You should not recreate data for years that the monitor was not operational because of the further uncertainty that this data adds. If less than three year s of complete data are not available, consultation with EPA is recommended. The Tracking guidance suggests that a case-by-case proposal on how this data should be processed s hould be developed in consulta tion with EPA OAQPS (and the Regional Office).

12. How are international emissions and natu ral events addressed in the RH SIPs?

EPA addressed the treatment of internationa l emissions in the 1999 RHR in a discussion of the long-term strategy for making reasona ble progress in section III.G of the preamble to the final regional haze rule as follows:

"The EPA agrees that the projected emissions from international sources will in some cases affect the ability of States to meet reasonable progress goals. The EPA does not expect States to restrict emissions from domestic sources to offset the impacts of international transport of pollution. We believe that States should evaluate the impacts of current and projected emissions from inte rnational sources in their regional haze programs, particularly in cases where it ha s already been well documented that suchEPA Q and A - September 26, 2006 20 sources are important. At the same time, EP A will work with the governments of Canada and Mexico to seek cooperative solutions on transboundary pollution problems." 64 Fed. Reg. 35714, 35736 (July 1, 1999).

EPA provided additional clarification in th e preamble to the 1999 RHR on how States should properly evaluate in ternational emissions, when we discussed the States' obligation to submit five-year reports evalua ting progress toward the RPG for each Class

I area:

"If the State finds that intern ational emissions sources are responsible for a substantial increase in emissions affecting visibility conditions in any Class I area or causing a deficiency in plan implementation, the Stat e must submit a techni cal demonstration to EPA in support of its finding. If EPA agr ees with the State's finding, EPA will take appropriate action to address the international emissions through available mechanisms. Appropriate mechanisms for addressing visibi lity-impairing emissions from international

sources are further discussed in unit III.G on the long-term strategy." 64 Fed. Reg. at

35747.

Both in explaining RPGs and in assessing wh ether current implementa tion plan strategies are achieving them, States can take into acc ount the nature of inte rnational emissions. For instance, after having a pplied the four statutory fact ors and calculate d their RPGs,

states can at their discreti on, quantify the effects of inte rnational emissions on their ability to reach RPGs. However, States s hould not directly cons ider the effects of international emissions when calculating thei r uniform rates of progress by either adding the effects of international emissions to their estimates of natural conditions, or by subtracting international emissi ons from current conditions. Either of these approaches

conflicts with the basic definitions of "cur rent conditions" (baseline conditions for the first SIP) and "natural conditions," as described in the 1999 RHR. 64 Fed. Reg. 35728, (July 1, 1999).

Those natural events most commonly linked to RH are wind blown dust and emissions from biomass burning. EPA has long recognized th e natural role of fire in the ecosystem. Consequently, in determining natural background for a Class I area, EPA believes States should be permitted to consider some amount of fire in the calculation. If a State finds during the five year period review that an unusual natural event such as a large wildfire is affecting progress, this can be taken into acc ount in its assessment of whether the current

SIP are sufficient to meet the RPGs. The State should submit a technical demonstration showing its estimate of the wildfires’ contribu tion to visibility impairment to support its

conclusion.EPA Q and A - September 26, 2006 21 APPENDIX: Question 5 cost equations

Average cost for an individual source

Average cost of control option A = annualized ca pital + operating and maintenance $ option A / tons removed option A

Average cost of control option B = annualized ca pital + operating and maintenance $ option B / tons removed option B

We use the following definitions for analyzi ng control options acro ss a source category or subcategory:

Average of individual source costs :

Average of individual source costs of control option A =

control costs source 1 / tons removed source 1 + control costs source 2 / tons removed source 2

....

------------------ ------------------ ----------------- ------------------ --------------- -------------- total number of sources

Average cost over the category :

Average cost over the cate gory of control option A =

control costs source 1 + control costs source 2

....

------------------ ------------------ ----------------- ------------------ --------------- -------------- tons removed source 1+ tons removed source 2

....