ABSTRACT LEGISLATIVE AND REGULATORY BACKGROUND

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1 Title: Summary of Determinations for Coal-Fired Authors: Carl V. Weilert, Katherine Zack and Novi Leigh, Burns & McDonnell Engineering Presented at: Power-Gen Renewable Energy & Fuels Conference Date: Feb , 2008 ABSTRACT Electric generating units () are one of 26 source categories subject to the provisions of the Regional Haze Rule (RHR) related to the determination of Best Available Retrofit Technology () for control of emissions of sulfur dioxide (SO 2 ), nitrogen oxides (NO x ) and particulate matter (PM). Each state was required to develop and submit to the U.S. Environmental Protection Agency (EPA) by Dec. 17, 2007, a state implementation plan (SIP) that included the determination of for sources that were determined to be subject to. This paper presents a summary of the results of determinations for coal-fired as included in the RHR SIPs submitted to the EPA by the states. All available information on unit-specific determinations for coal-fired from each final state plan that had been submitted to the EPA as of October 2008 was considered in the preparation of the summary. An analysis of the emission limitations established as for each of the three pollutants is presented. The results for SO 2 and NO x are compared to the presumptive emission rates as established by the EPA in its July 2005 Guidelines. [Note that EPA did not establish presumptive limits for PM.] LEGISLATIVE AND REGULATORY BACKGROUND The legal authority for is derived from 169A of the Clean Air Act (CAA). This section of the act establishes the lofty goal of completely eliminating the effects of industrial pollution on the public s view of scenic vistas in national parks and similar areas where visibility is an important value: Congress hereby declares as a national goal the prevention of any future, and the remedying of any existing, impairment of visibility in mandatory class I Federal areas, which impairment results from manmade air pollution. CAA 169A(a)(1) In its plan for implementation of this goal, the EPA has promulgated a regulatory program known as the RHR, which is codified at 40 CFR 51, subpart P. The RHR sets the deadline for attainment of the elimination of manmade visibility impairment in Class I areas as the year Class I areas for which visibility was judged to be an important value are displayed in Figure 1. The color coding indicates the Federal Land Manager with primary Page 1 of 11

2 responsibility for each area, where NPS = National Park Service, FWS = Fish and Wildlife Service, and FS = Forest Service. These class I areas are located in 35 states. However, because regional haze is caused by long range transport of pollutants, each state is required by the RHR to assess the of sources within its borders on nearby class I areas. Figure 1. Federal Class I Areas The RHR tasks the states with performing a number of activities related to the evaluation and control of regional haze: Establish current baseline visibility for each class I area based on data from 2000 to 2004 Determine the natural background visibility Determine the uniform progress needed to attain natural background visibility within 60 years from 2004 (i.e. 2064) Develop a 10-year plan that will include enforceable emission reductions that puts each class I area on the glide path toward the 2064 goal Consult with other states in plan development Update the plan every 10 years Page 2 of 11

3 To facilitate consultation between states with regard to regional haze, the EPA has promoted the establishment of regional planning organizations (RPOs). Figure 2 displays the boundaries of the five RPOs that have been established. Figure 2. Regional Planning Organizations REQUIREMENTS FOR One of the key requirements of the RHR is the establishment of for the control of visibility-impairing pollutants. The implementation of is required by 169A(b)(2)(A) of the Clean Air Act as a means to begin progress toward the national goal of elimination of manmade visibility impairment. As defined in the RHR: Best Available Retrofit Technology () means an emission limitation based on the degree of reduction achievable through the application of the best system of continuous emission reduction for each pollutant, which is emitted by an existing stationary facility. The emission limitation must be established, on a case-by-case basis, taking into consideration the technology available, the costs of compliance, the energy and non-air quality environmental s of compliance, any pollution control equipment in use or in existence at the source, the remaining useful life of the source, and the degree of improvement in visibility, which may reasonably be anticipated to result from the use of such technology. 40 CFR Page 3 of 11

4 The RHR requires that each regional haze SIP include the identification of all units that are -eligible. To be -eligible, a source must meet the following criteria: Belongs to one of 26 listed source categories, including Started operations after Aug. 7, 1962, 15 years before the date of enactment of the Clean Air Act amendments of 1977 Was in existence on Aug. 7, 1977, the date of enactment of the Clean Air Act amendments of 1977 Has the potential to emit 250 tons per year or more of SO 2, NO x or PM Each state, in developing its regional haze SIP, must determine whether the eligible sources are subject to. A source will be subject to if it is shown to cause or contribute to visibility impairment in any class I area. In its Guidelines for Best Available Retrofit Technology () Determinations, as published in the Federal Register on July 6, 2005, the EPA established criteria for judging the degree of visibility impairment. The deciview (dv) is a haze index used to assess visibility impairment. Any source shown to be responsible for a visibility of 1.0 deciview or more at any class I area is said to cause visibility impairment. Any source with an of at least 0.5 dv is said to contribute to visibility impairment. The EPA requires that the CALPUFF model be used for determination of visibility impairment. According to the EPA, the CALPUFF model is generally intended for use on a scale for areas 50 to several hundred kilometers from a source. As illustrated on Figure 3, this means that most -eligible sources fall within the potential zone extending out from one or more class I areas. Also, some sources may visibility in multiple class I areas located in more than one state. Due to the extensive modeling effort required for these determinations, some states have relied upon modeling done by the RPOs. Page 4 of 11

5 Figure 3. Class I Areas and Modeling Zones of Influence in Relation to -Eligible Sources If a state identifies a source that causes or contributes to visibility impairment in a class I area, then it must include in its regional haze SIP a determination for that source. In accordance with the guidelines, many states required the source owners to complete a analysis that took into account the five statutory factors from the CAA 169A(g)(2). 1. The cost of controls 2. Energy and non-air quality environmental s 3. Existing controls at the source 4. The remaining useful life of the source 5. The visibility improvement reasonably expected from application of the controls INTERRELATION OF WITH CAIR When the EPA developed the Clean Air Interstate Rule (CAIR), it performed a modeling analysis that indicated that the SO 2 and NO x emission reductions achieved under the cap and trade provisions of that rule would provide a degree of reduction in visibility impairment in class I areas that was better than. Consequently, the EPA offered the option for the 28 states in the CAIR region, as shown in Figure 4, to exclude from in the development of their regional haze SIPs. States that took this option would still need to consider for PM. Page 5 of 11

6 Figure 4. States Covered by CAIR States not covered by CAIR States controlled for fine particles (annual SO 2 and NO x ) States controlled for both fine particles (annual SO 2 and NO x ) and ozone (ozone season NO x ) States controlled for ozone (ozone season NOx) PRESUMPTIVE EMISSION RATES As part of its guideline, the EPA established presumptive emission levels for that are to be applied to individual larger than 200 megawatts (MW) at plants with total capacity of 750 MW or more. The guideline established presumptive control levels for SO 2 and NO x, but not for PM. For SO 2, the presumptive for without existing SO 2 controls is 95% removal or 0.15 lb/mmbtu. For with existing flue gas desulfurization (FGD) systems, the presumptive control depends on the removal efficiency of the existing FGD system. with FGDs that have removal efficiencies below 50% are expected to replace the FGD system. Units with FGDs having removal efficiencies at or above 50% Page 6 of 11

7 are expected to upgrade the existing system to improve the removal efficiency. The guideline listed some specific FGD upgrade options that should be evaluated, but it stopped short of defining a numerical emission limit or removal efficiency that would apply. A case-by-case determination would be required. For NO x, the presumptive for also depends on whether the unit has existing controls or not. For equipped with post-combustion NO x controls selective catalytic reduction or selective non-catalytic reduction that operate seasonally, the presumptive includes yearround operation of the existing controls. For units without post-combustion control, the EPA established specific presumptive NO x emission limits based on the coal type and boiler type, as displayed in Figure 5. Figure 5. Presumptive Emission Levels for NO x as a Function of Boiler Type and Coal Type NOx Presumptive Limit (lb/mmbtu) Dry-Bottom Wall-Fired Tangentially-Fired Cell Burners Dry Turbo-Fired Wet-Bottom Tangential 0.62 Cyclones Bituminous Subbituminous Lignite STATUS OF REGIONAL HAZE SIP SUBMITTALS The RHR required all 50 states to submit their regional haze SIPs no later than Dec. 17, Only a few states complied with this deadline. In June 2008, Earthjustice notified EPA Administrator Stephen Johnson that it intended to file a civil suit to compel the EPA to meet its statutory requirement to rule on the adequacy of the state plans. The CAA requires the EPA to determine, within six months of a SIP submittal deadline, whether Page 7 of 11

8 each state subject to that deadline has met its requirements. The EPA took no action in response to the notification by Earthjustice, and a lawsuit (Environmental Defense Fund and National Parks Conservation Association v. Stephen L. Johnson) was filed in the U.S. District Court for the District of Columbia on Oct. 21, In the filing for the case, it was noted that: Plaintiffs are informed and believe that, as of the date of this complaint, only 14 states and other jurisdictions have submitted haze SIPs purporting to meet the above described requirements. Accordingly, plaintiffs allege on information and belief that the vast majority of states required to submit haze SIPs by Dec. 17, 2007, have as yet failed to do so. Coincidentally, on the same day that the lawsuit was filed, Bill Harnett of the EPA made a presentation to the membership meeting of the National Association of Clean Air Agencies. In that presentation, Harnett listed 13 states and one other jurisdiction that had submitted final regional haze SIPs to the EPA. These are listed in Table 1 below: Table 1. Regional Haze SIPs Submitted to the EPA Alabama Kentucky South Carolina* Albuquerque Louisiana Tennessee* Arkansas Mississippi Utah Delaware Missouri* West Virginia Iowa* North Carolina* *Deemed complete by the EPA. Source: These 14 SIPs were obtained from the regulatory agencies that had submitted them and were then reviewed as the basis for the analysis presented in this paper. It is interesting to note that only one of the states, which had submitted its final regional haze SIP to the EPA as of Oct. 21, 2008, was a non-cair state, Utah. Twelve of the 28 CAIR-affected states had submitted a final regional haze SIP to the EPA as of Oct. 21, SUMMARY OF DETERMINATIONS FOR Review of the regional haze SIP submittals for the analysis presented in this paper concentrated on the treatment of coal-fired in the development of. As described previously, there are two mechanisms that would allow excluding a given -eligible EGU from being subject to. One is to demonstrate via CALPUFF modeling that the visibility impairment of that EGU on any class I area is below 0.5 dv, which is the EPA s threshold for contributing to visibility impairment. The other, for an EGU in a CAIR-affected state, is for the state agency to elect to adopt the EPA protocol that CAIR is better than when establishing for within the state. This would eliminate Page 8 of 11

9 the need to determine for SO 2 or NO x emissions from those, but the task of establishing for PM would still remain. The first level of analysis of the SIP documents for each of the 14 jurisdictions that had submitted a final plan to the EPA was to review and tabulate the extent to which the SIP was about to exclude coal-fired from using one or both of these mechanisms. The results of this first round of comparisons are presented in Table 2. Table 2. Treatment of -Eligible Coal-Fired in Final Regional Haze SIPs State or City for SO 2 for NO x for PM Alabama Albuquerque No -eligible in the city No -eligible in the city No -eligible in the city Arkansas Limits set for 3 Limits set for 3 Existing ESPs satisfy Delaware Existing state rule is better than Existing state rule is better than Existing ESP, ESP + DSI Iowa Kentucky Limits set for 8 Louisiana Mississippi Missouri North Carolina South Carolina Tennessee Limits set for 2 Utah Limits set for 4 Limits set for 4 Limits set for 4 West Virginia Limits set for 3 From Table 2, it can be seen that only nine had emission limits for SO 2 established as a result of a determination included in a final SIP submitted to the EPA. For NO x, this number is seven. For particulate, only 15 were given specific emission limits in a final SIP determination. Page 9 of 11

10 These numbers are all much smaller than the authors anticipated when the concept for this paper was developed. The reasons for this poor turnout are not entirely clear. While it is true that the status of CAIR was in doubt during the second half of 2008, this uncertainty did not exist at any time prior to the Dec. 17, 2007, deadline for submittal of regional haze SIPs. Furthermore, of the 22 states that are not affected by CAIR in any way, only one had submitted its final SIP by the Oct. 21, 2008, cutoff used for the development of this analysis. Although the number of for which specific emission limits for a visibility-impairing pollutant were included in a final regional haze SIP is fairly small, it is nevertheless instructive to compare the values of these emission limits. Table 3 presents a tabulation of all emission limits included in the five SIPs that included specific limits. Table 3. Coal-Fired EGU Limits (lb/mmbtu) in Final Regional Haze SIPs State Unit(s) for SO2 for NOx for PM AR Flint Creek NA AR White Bluff 1 & 2 on subbituminous coal NA AR White Bluff 1 & 2 on bituminous coal NA KY Big Sandy 1 NA NA lb/hr H 2 SO 4 KY Big Sandy 2 NA NA lb/hr H 2 SO 4 KY Cooper 1 & 2 NA NA KY Mill Creek 3 & 4 NA NA for SO 3 KY Spurlock 1 & 2 NA NA 0.03 TN Cumberland 1 & NA NA UT Hunter 1 & UT Huntington 1 & WV Mt. Storm 1, 2 & 3 NA NA 0.03 COMPARISON TO PRESUMPTIVE LEVELS Referring to Table 3 above, it can be seen that seven of the nine for which emission levels were set for SO 2 have emission limits at or below the EPA s established presumptive emission limit of 0.15 lb/mmbtu. The only exceptions to this are Cumberland Units 1 and 2. However, it should be noted that the Cumberland units are equipped with existing FGD systems. As noted previously, there is not a specific presumptive SO 2 emission limit for with existing FGD. Furthermore, unlike the other units listed in Table 3, the Cumberland units fire high sulfur coal, so their emissions would not be expected to be comparable to those of the other units listed. Page 10 of 11

11 For NO x, as displayed on Figure 5, the presumptive emission limit is a function of both the coal rank and the boiler type. Of the units listed in Table 3 for which emission levels have been established for NO x, all except Flint Creek are tangentially fired. Of these T-fired boilers, the Hunter and Huntington units fire bituminous coal and are, therefore, subject to a presumptive NO x emission limit of 0.28 lb/mmbtu. As shown above, the emission limit for these units, as established in the Utah regional haze SIP, is below the presumptive level. The other units for which NO x emission limits have been established have all been given emission limits that match exactly the corresponding presumptive emission limits for NO x. The EPA did not establish a presumptive emission limit for PM. From a review of the information in Table 3 it can be seen that for units, which were given a specific PM emission limit, the most common emission limit for PM was 0.03 lb/mmbtu, with seven units receiving this limit. Four units were given limits for PM of 0.05 lb/mmbtu. Four units were given specific emission limits for the condensable fraction of PM as represented by sulfuric acid mist precursors (SO 3 or H 2 SO 4 ). SUMMARY AND CONCLUSIONS A review of determinations included in final regional haze SIPs that were submitted to the EPA on or before Oct. 21, 2008, has been conducted. Surprisingly, only 13 of 50 states had submitted their SIPs in time for inclusion in this analysis, despite the fact that the regulatory deadline for these submittals was Dec. 17, Only one of the 13 SIPs reviewed was for a state outside the region affected by CAIR. It is unclear why so few SIPs from non- CAIR states were submitted by the deadline or 10 months beyond the deadline. Of the SIPs reviewed for CAIR-eligible states, most took advantage of the EPA s CAIR is better than protocol for SO 2 and NO x emissions from. All states still needed to identify units that were subject to for PM emissions, but in most cases the states were able to demonstrate that most, if not all, of the -eligible were below the level of visibility impairment corresponding to EPA s definition of contribution to visibility impairment. Only five states included specific emission levels for any in their regional haze SIPs. Of those that did, virtually all of the emission levels established as were at or below the corresponding presumptive emission levels that had been established by EPA in the guideline. Page 11 of 11