### BEST AVAILABLE RETROFIT TECHNOLOGY ANALYSIS TVA PARADISE FOSSIL PLANT

July 16, 2007

### CONTENTS

Section Page

I. Introduction.......................................................................................1

II. BART Engineering Analysis..................................................................3

III. BART Modeling Analysis.....................................................................7

IV. Conclusions....................................................................................16

Appendix--Cost of Compliance Details1 

### I. Introduction

Guidelines for Best Available Retrofit Tec hnology (BART) evaluations have been issued by the U. S. Environmental Protection Agency (EPA) in the Federal Register (70 FR 39104-39172). A BART determination is required for any eligible source that “emits any air pollutant which may reasonably be anti cipated to cause or contribute to any impairment of visibility” within any of the 156 mandatory Class I federal areas. A source is considered to cause visibility impairment if it is responsible for a 1.0 deciview (dv) change in visibility; it is considered to contribute to visibility impairment if it is responsible for a 0.5 dv change in visibility.

Major stationary sources are BART-eligible if they meet three criteria: (1) Potential to emit at least 250 tons pe r year of a visibility -impairing pollutant. (2) “Commenced construction” as of August 7, 1977, but not in operation more than 15 years (August 7, 1962). (3) Belong to one of the 26 listed source categories in the guidance.

If an eligible source is concluded to be subj ect to BART, determina tion of the appropriate control alternative must consider the following statutory factors: (1) existing control equipment (2) cost of compliance (3) energy and non-air environmental impacts (4) remaining useful life of the source (5) degree of visibility improvement e xpected from the application of controls

The TVA Paradise Fossil Plant (PAF), lo cated in Muhlenberg County, KY, has three pulverized-coal, cyclone steam generators that are considered BART eligible. Units 1 and 2 are nominally rated at about 704 MW each, a nd Unit 3 is nominally rated at about 1150 MW. All three units are equipped with flue gas desulfurization (FGD) systems for sulfur dioxide (SO 2 ) control and selective catalytic redu ction systems for controlling nitrogen oxides (NO x ). Units 1 and 2 use wet venturi scrubbe rs to control particulate matter (PM) emissions, and Unit 3 uses an el ectrostatic precipitator (ESP).

All three units at PAF are subj ect to the EPA Clean Air Interstate Rule (CAIR). Based on guidance from EPA and the Kentucky Di vision for Air Quality (KDAQ), compliance with CAIR satisfies BART requirements for SO 2 and NO x emissions at electric generating units. As a result, this BART analysis only considers PM 10 emissions.

Two Class I areas are locate d within 300 km of PAF: Mammoth Cave National Park (MACA) and Mingo Wilderness Area (MING). The locations of the PAF stacks, the two class I areas that are within 300 km, and the VISTAS 12-km and 4-km grid for domain 3 are shown in Figure 1.2 Figure 1. Location of PAF and Class I Areas within 300 km (Mammoth Cave National Park (MACA) and Mingo Wilderness Area (MING)). The red box shows the VISTAS 12-km domain, and the green box shows the VISTAS domain #3, the 4-km subdomain that will be used in BART modeling for PAF.

As discussed in Section III, exemption modelin g showed that all three units at PAF are subject to BART requirements for PM 10 . Therefore, an engineering analysis was required to determine whether there is a technically and economically feasible control scenario that represents BART. The modeling analysis also demonstrated that approximately 90 percent of the visibility impacts at the aff ected Class I areas can be attributed to condensable PM 10 emissions (i.e., SO 3 ). So the engineering evaluation for PAF focuses on control of SO 3 /H 2 SO 4 emissions.3 

### II. BART Engineering Analysis

Based on emissions testing at PAF, Units 1 and 2 emit approximately 17.7 ppmdv SO 3 , and Unit 3 emits approximately 17.6 ppmdv SO 3 (both corrected to 3%0 2 ). These values were used as the baselines for the engineering analysis.

Two options were identified as tec hnically feasible for controlling SO 3 emissions at PAF: wet ESPs and hydrated lime injection. An ESP controls PM by imparting a negative charge to fly ash particles entering the device and collecti ng them on positively charged plates. In a wet ESP, the fly ash is removed by flushing the collection plates with water. Wet ESPs are very expensive, requiring larg e capital investments. They also require large volumes of water for cleaning the plates . This technology is capable of about 90% SO 3 removal, so it was evaluated at an emi ssion level of 1.8 ppmdv. It should be noted, however, that the vendor guarantee accompa nying the capital cost quote that TVA received for this equipment e quated to about 3 ppmdv SO3 (3%O 2 ).

Lime injection involves injec ting hydrated lime in the conve ctive pass or ductwork of the boiler. The lime reacts with SO 3 to form calcium sulfate, which is removed downstream by the PM control device. TVA plans to inst all lime injection systems on all three units at PAF to mitigate opacity. These systems will be installed well before the regulatory deadline for implementing BART. However, be cause they are not currently installed and operating, lime injection is included as a c ontrol option in the BART analysis.

Lime injection testing on Unit 2 demonstrated an achievable SO 3 emission level of approximately 7 ppmdv (3%O2). Because Unit 1 is similar to Unit 2, the same emission level would apply. Testing on Unit 3 has not been completed, so an achievable emission level has not been established. For the purposes of this analysis, an SO 3 emission level of 7 ppmdv was assumed. The analysis for Unit 3 may have to be revised after testing is completed if that emission rate cannot be achieved without negativ e impacts to existing particulate control equipment.4 The top-down matrix of BART op tions is presented in Table 1.

Table 1. BART Hierarchy of Options

Control Option Achievable Emission Rate (ppmdv SO 3 @ 3%O 2 ) Comments

Wet ESP 1.8 • High capital cost

• Large volumes of water required

• Vendor guarantee of only 3 ppm@3%O 2

• Controls all PM 10 components Lime Injection 7.0 • Lower capital cost

• High operating costs for reagent

• Achievable emission level not verified by testing for Unit 3

Cost of Compliance

Costs were estimated for both control options . Capital equipment costs for the wet ESP were obtained from a vendor quote (“Budgetary Proposal, Paradise Units 1 & 2, Babcock & Wilcox Company, July 3, 2007”). This quot e applies to Units 1 and 2, but it was scaled using engineering assumptions for use with Unit 3. Capital costs for lime injection systems and annual reagent costs were based on TVA experience with similar equipment at other TVA locations. Other capital and a nnual costs were based on information in the EPA Air Pollution Control Cost Manual, Sixth Edition

. A summary of results from the cost analysis are presented in Table 2. Details can be found in the Appendix to this re port. The total capital inve stment for a wet ESP ranges from about $100 million for Unit 1 or 2 to almost $156 million for Unit 3. Total annual costs range from about $29 million to $44 millio n per year. The corresponding total cost effectiveness ranges from $27,594 to $39, 263 per ton of SO 3 /H 2 SO 4 . Incremental cost effectiveness compared to lime injecti on ranges from $77, 821 to $82,940 per ton. Based on these results, a wet ESP is clearly ec onomically infeasible for PAF and should, therefore, be eliminated from consideration as a basis for BART.

The total capital investment for hydrated lim e injection ranges from $4.2 million for Unit 1 or 2 to $8.4 million for Unit 3. Total a nnual costs range from about $2.3 million to $4.4 million per year. The corresponding co st effectiveness ranges from $3,265 to $6,776 per ton of SO 3 /H 2 SO 4 . Although considerably less ex pensive than a wet ESP, the cost effectiveness values for lime injection are still too high to be considered as an acceptable cost of compliance for BART.5 Non-air Environmental Impacts

As stated previously, a wet ESP is a water intensive system. According to the EPA Air Pollution Control Cost Manual , a wet ESP uses at least 5 gal/min of water per 1,000 cfm of flue gas. Based on this ratio, operati ng wet ESPs on all three units at PAF would consume about 16 billion gallons per year of additional water and require treatment of an equivalent volume of wastewater.6Table 2. BART Cost of Compliance SummaryUnit 1 Unit 2 Unit 3Lime Injection Wet ESP Lime Injection Wet ESP Lime Injection Wet ESPEmission Reductionfrom Baseline(tons/yr)697 1,035 705 1,047 644 1,123IncrementalEmission Reduction(tons/yr) -- 338 -- 342 -- 479Total CapitalInvestment ($) 4,200,000 100,216,875 4,200,000 100,216,875 8,400,000 155,948,800Total AnnualizedCost ($/yr) 2,301,659 28,877,504 2,301,659 28,877,504 4,363,849 44,092,044Total CostEffectiveness ($/ton) 3,305 27,914 3,265 27,594 6,776 39,263Incremental CostEffectiveness ($/ton) -- 78,627 -- 77,821 -- 82,9407 

### III. BART Modeling Analysis

TVA conducted BART modeling for PAF follo wing both the general VISTAS protocol and the revised TVA BART protocol subm itted to the Kentucky Division for Air Quality on July 17, 2006. Modeling was conducted on the VISTAS 4-km domain for the state of KY (dom 3). Two Class I areas ar e located within 300 km of PAF: Mammoth Cave (MACA) at 63.3 km and Mingo (MING) at 283 km. Stack parameters are presented in Table 3.

Table 3. Stack Parameters for PAF

Stack Parameter Unit 1 Unit 2 Unit 3 Stack Height (m) 182.9 182.9 182.9 Base Elevation (m) 129 129 129 Stack Diameter (m) 7.92 7.92 11.3 Gas Exit Velocity (m/s) 22.7 22.7 15.4 Stack Gas Exit Temperature ( o K) 333 333 329

Exemption Modeling

CALPUFF modeling was conducted following the example files that were made available by Earth Tech, Inc. Following the example files, PM emissions were set to 1 g/s for all size categories. The emission rate for SO 3 was entered as H 2 SO 4 in g/s as indicated on the “BART” worksheet of the emissions spreadsheet “PAF_CY06_BART.xls,” which was submitted with the revised modeling protocol document. All emissions for the modeling anal ysis were calculated assuming operation at maximum heat input to conservatively repr esent maximum 24-hour actual emissions. Emissions of HNO 3 and PM-NO 3 were set to zero, because no credible emissions factors were available for these species for EGUs. Support for setting HNO 3 and PM-NO 3 to zero was found in some SMOKE emissions factors provided by VISTAS. In the SMOKE emissions table provi ded by VISTAS, the factor provided for PM-NO 3 was zero, as shown in Table 4. The SMOKE emi ssions factors were not used except as justification for sett ing emissions of HNO 3 and NO 3 to zero.

Table 4. Emissions profiles from SMOKE for EGUs (provided by VISTAS).

profile Pllt species split divisor mass_frac

22001 PM2_5 PEC 0.0183 1 0.0183

22001 PM2_5 PMFINE 0.852 1 0.852

22001 PM2_5 PNO3 0 1 0

22001 PM2_5 POA 0.0107 1 0.0107

22001 PM2_5 PSO4 0.119 1 0.1198 CALPUFF exemption modeling on the 4-km domain was conducted as follows:

1. A CALPUFF simulation was conducted us ing the VISTAS-approved version of CALPUFF (version 5.754) for each unit of PAF for each of the three years, 2001, 2002 and 2003. 2. Emission factors entered in the POSTUTIL control file are shown in Table 5. These factors were calculated in the sp readsheet “pm_distribution_PAF.xls” from the emissions values in the electron ic workbook PAF_CY06_BART.xls following the example spreadsheet pm-distributi on-sample-source, which was provided by Earth Tech. 3. POSTUTIL version 1.52, level 060412 was run on each output file from step 1. 4. The outputs from POSTUTIL were summed across the three units. 5. CALPOST version 5.6393, level 060202 was run separately for each class I area on the output from step 4. Method 6 was used. The baseline was based on the annual average for each Class I area, taken from Appendix B of Guidance for Estimating Natural Visibility Condi tions Under the Regional Haze Rule , EPA 454/B-03-005, published in September, 2003. The f(RH) values were taken from Table A-3, Monthly Site-Sp ecific f(RH) Values for Each Mandatory Federal Class I Area, Based on the Centroid of the Area (Supplemental Information), found in the same EPA document. 6. The lists of delta dv in the CALPOST.LST files for each of the 3 years were used to get the 98 th percentile for each individual year, the 8 th highest value. The data from the 3 years were combined togeth er and sorted by de lta dv to find the 98 th percentile value (22 nd highest value) for the three years combined.

Results from the 4-km simulations are presented in Tables 6 and 7.9 Table 5. Emission Rates for PAF Used in POSTUTIL for Exemption Modeling

Species Unit Emission Rate (g/s) PM800 PM425 PM187 PM112 PM081 PM056 Total* PM10 1 111.8 PMC 1 11.1531 18.5892 29.74 SOIL 1 12.5307 4.4751 14.0233 1.1922 32.22 EC 1 0.4814 0.1719 0.5388 0.0458 1.24 H2SO4 1 45.08 SOA 1 1.7539 1.7539 3.51 NO3/ HNO3 1 0

PM10 2 113. PMC 2 11.5206 19.2013 30.72 SOIL 2 12.9432 4.6227 14.4854 1.2316 33.28 EC 2 0.4973 0.1776 0.5566 0.0473 1.28 H2SO4 2 45.01 SOA 2 1.7512 1.7512 3.50 NO3/ HNO3 2 0

PM10 3 116.8 PMC 3 6.5827 10.9705 SOIL 3 7.3955 2.6414 8.2766 0.7039 19.02 EC 3 0.2841 0.1015 0.3180 0.0270 0.73 H2SO4 3 73.70 SOA 3 2.8870 2.8870 5.77 NO3/ HNO3 3 0

T able 6. Summary of CALPUFF Resu lts for PAF on 4-km Grid.

Class I Area Dist (km) from

source to nearest receptor # Days with 98 th Percent > 0.5 dv,

98 th percentile, in Class I Area (2001) # Days with 98 th Percent > 0.5 dv,

98 th percentile, in Class I Area (2002) # Days with 98 th Percent > 0.5 dv,

98 th percentile, in Class I Area (2003) # Days with 98 th Percent > 0.5 dv,

98 th percentile in Class I Area for 3-Year Period (2001- 2003)

Delta dv Used 8th highest 8th highest 8th highest 22nd highest Mammoth Cave National Park, KY 63.3 101 3.62 76 3.45 96 3.93 273 3.86

Mingo Wilderness Area, MO 283 9 0.595 22 0.865 8 0.527 39 0.72310 Table 7. 98 th Percentile Results for Paradise-Impacted Class I Areas. (DeltaDeciview Rankings #1-22 Shown for 2001-2003.)

CLASS I AREA: Mammoth Cave

Rank Year Day Delta dv
1 2001 32 6.95 2 2001 361 6.11 3 2003 123 5.89 4 2002 245 5.35 5 2002 59 5.34 6 2003 14 5.24 7 2002 237 4.89 8 2003 263 4.77 9 2001 241 4.60 10 2001 216 4.55 11 2001 312 4.39 12 2001 73 4.38 13 2002 291 4.35 14 2003 20 4.17 15 2003 161 4.07 16 2003 340 4.01 17 2002 316 3.98 18 2003 329 3.97 19 2002 362 3.95 20 2003 167 3.93 21 2003 169 3.88 22 2002 212 3.86 CLASS I AREA: Mingo

Rank Year Day Delta dv
1 2001 177 1.44 2 2002 269 1.40 3 2002 39 1.28 4 2002 257 1.20 5 2003 254 1.18 6 2001 95 1.17 7 2001 79 1.16 8 2002 174 1.13 9 2002 222 1.10 10 2003 53 1.07 11 2001 247 1.04 12 2003 348 0.999 13 2002 345 0.995 14 2001 256 0.887 15 2003 173 0.884 16 2002 270 0.871 17 2002 253 0.865 18 2002 160 0.855 19 2002 243 0.835 20 2001 178 0.827 21 2002 216 0.824 22 2002 273 0.723

Because exemption modeling for PAF showed impacts greater than 0.5 dv at both MACA and MING, all three units at PAF are subject to BART requirements, and an engineering analysis and determination modeling were conducted.

Determination Modeling

The BART determination modeling for PAF wa s conducted for each unit. Because Units 1 and 2 have similar design and operating pa rameters, determination modeling conducted for Unit 1 was considered applicable to both units. Determination modeling was conducted separately for Unit 3. The control options that were modeled are presented in Table 8.11 Table 8. Control Options for BART Determination Modeling

Unit 1 or 2 Unit 3

Control Option SO 3 Emissions (ppm H 2 SO 4 ) Filterable Particulate Emissions (lbs/MMBtu) SO 3 Emissions (ppm H 2 SO 4 ) Filterable Particulate Emissions (lbs/MMBtu)
Baseline level 17.7 0.110 17.6 0.038 Lime Injection 7.0 0.110 7.0 0.038 Wet ESP 1.8 0.015 1.8 0.015

CALPUFF determination modeling on the 4- km domain was conducted as follows:

1. A CALPUFF simulation was conducted us ing the VISTAS-approved version of CALPUFF (version 5.754) for each of the three years, 2001, 2002 and 2003. Separate simulations were conducted fo r each of the options in the modeling matrix. 2. Emission factors entered in the POSTUTIL control file are shown in Table 9. These factors were calculated in the sp readsheet “pm_distribution_PAF.xls” from the emissions values in the elec tronic workbook “PAF_CY06_BART.xls” following the example spreadsheet pm-distribution-sample-source, which was provided by Earth Tech. Fact ors were calculated separate ly for each option in the modeling matrix. 3. POSTUTIL version 1.52, level 060412 was run on each output file from step 1. 4. CALPOST version 5.6393, level 060202 was run separately for each class I area on the output from step 3. Method 6 was used. The baseline was based on the annual average for each Class I area, taken from Appendix B of Guidance for Estimating Natural Visibility Condi tions Under the Regional Haze Rule , EPA 454/B-03-005, published in September, 2003. The f(RH) values were taken from Table A-3, Monthly Site-Sp ecific f(RH) Values for Each Mandatory Federal Class I Area, Based on the Centroid of the Area (Supplemental Information), found in the same EPA document. 5. The lists of delta dv in the CALPOST.LST files for each of the 3 years were used to get the 98 th percentile for each individual year, the 8 th highest value. The data from the 3 years were combined togeth er and sorted by de lta dv to find the 98 th percentile value (22 nd highest value) for the three years combined.12 Table 9. Emission Rates for PAF Used in POSTUTIL for Determination Modeling

Species Unit/Run Emission Rate (g/s) PM800 PM425 PM187 PM112 PM081 PM056 Total* PM10 1-base 111.8 PMC 1-base 11.1531 18.5892 29.74 SOIL 1-base 12.5307 4.4751 14.0233 1.1922 32.22 EC 1-base 0.4814 0.1719 0.5388 0.0458 1.24 H2SO4 1-base 45.08 SOA 1-base 1.7539 1.7539 3.51 NO3/ HNO3 1-base 0

PM10 1-lime 84.51 PMC 1-lime 11.1531 18.5892 29.74 SOIL 1-lime 12.5307 4.4751 14.0233 1.1922 32.22 EC 1-lime 0.4814 0.1719 0.5388 0.0458 1.24 H2SO4 1-lime 17.80 SOA 1-lime 1.7540 1.7540 3.51 NO3/ HNO3 1-lime 0

PM10 1-WESP 17.03 PMC 1-WESP 1.5781 2.6302 SOIL 1-WESP 1.7730 0.6337 1.9849 0.1685 4.56 EC 1-WESP 0.0681 0.0243 0.0763 0.0065 0.18 H2SO4 1-WESP 4.58 SOA 1-WESP 1.7538 1.7538 3.51 NO3/ HNO3 1-WESP 0

PM10 3-base 116.8 PMC 3-base 6.5827 10.9705 SOIL 3-base 7.3955 2.6414 8.2766 0.7039 19.02 EC 3-base 0.2841 0.1015 0.3180 0.0270 0.73 H2SO4 3-base 73.70 SOA 3-base 2.8870 2.8870 5.77 NO3/ HNO3 3-base 0

PM10 3-lime 72.39 PMC 3-lime 6.5827 10.9705 SOIL 3-lime 7.3955 2.6414 8.2766 0.7039 19.02 EC 3-lime 0.2841 0.1015 0.3180 0.0270 0.73 H2SO4 3-lime 29.31 SOA 3-lime 2.8871 2.8871 5.77 NO3/ HNO3 3-lime 0

PM10 3-WESP 28.0413 Species Unit/Run Emission Rate (g/s) PMC 3-WESP 2.5980 4.3311 SOIL 3-WESP 2.9189 1.0429 3.2675 0.2773 7.51 EC 3-WESP 0.1121 0.0401 0.1255 0.0107 0.29 H2SO4 3-WESP 7.54 SOA 3-WESP 2.8872 2.8872 5.77 NO3/ HNO3 3-WESP 0

Table 10. Summary of BART Determ ination Modeling Results for MACA

Delta dv 8th highest 8th highest 8th highest 22nd highest Unit/Run 2001 2002 2003 2001-2003 1-base 1.203 1.192 1.285 1.264 1-lime 0.567 0.567 0.606 0.594 1-WESP 0.155 0.156 0.166 0.162 3-base 1.740 1.624 1.842 1.819 3-lime 0.790 0.726 0.836 0.824 3-WESP 0.248 0.224 0.264 0.255

Table 11. BART Determination Mode ling Results for MACA (Delta dv)

1-base 1-lime 1-WESP 3-base 3-lime 3-WESP

1 2.654 1.307 0.367 3.339 1.575 0.506 2 2.205 1.068 0.297 2.980 1.389 0.442 3 2.097 1.026 0.285 2.948 1.375 0.439 4 1.980 0.966 0.269 2.894 1.355 0.436 5 1.841 0.873 0.240 2.649 1.216 0.379 6 1.695 0.802 0.220 2.367 1.094 0.350 7 1.656 0.793 0.219 2.338 1.063 0.330 8 1.624 0.765 0.210 2.316 1.054 0.327 9 1.556 0.743 0.205 2.257 1.025 0.318 10 1.554 0.731 0.200 2.163 0.980 0.314 11 1.528 0.718 0.197 2.138 0.980 0.311 12 1.468 0.704 0.195 2.118 0.975 0.303 13 1.456 0.701 0.193 1.992 0.904 0.283 14 1.455 0.700 0.192 1.946 0.887 0.281 15 1.408 0.663 0.183 1.930 0.875 0.273 16 1.330 0.635 0.175 1.891 0.857 0.269 17 1.323 0.627 0.171 1.886 0.856 0.268 18 1.313 0.621 0.170 1.881 0.850 0.265 19 1.285 0.614 0.168 1.842 0.836 0.264 20 1.284 0.606 0.166 1.834 0.828 0.258 21 1.281 0.605 0.166 1.831 0.825 0.258 22 1.264 0.594 0.162 1.819 0.824 0.25514 Table 12. Summary of BART Determ ination Modeling Results for MING

Delta dv 8th highest 8th highest 8th highest 22nd highest Unit/Run 2001 2002 2003 2001-2003 1-base 0.167 0.251 0.149 0.209 1-lime 0.077 0.116 0.069 0.097 1-WESP 0.021 0.031 0.019 0.026 3-base 0.273 0.381 0.239 0.325 3-lime 0.118 0.166 0.104 0.141 3-WESP 0.036 0.051 0.032 0.043

Table 13. BART Determination Mode ling Results for MING (Delta dv)

1-base 1-lime 1-WESP 3-base 3-lime 3-WESP

1 0.419 0.195 0.053 0.67 0.294 0.091 2 0.415 0.191 0.052 0.63 0.275 0.084 3 0.378 0.177 0.048 0.583 0.259 0.082 4 0.36 0.172 0.047 0.576 0.253 0.079 5 0.352 0.162 0.044 0.54 0.235 0.072 6 0.344 0.157 0.043 0.531 0.231 0.07 7 0.336 0.157 0.043 0.495 0.22 0.07 8 0.336 0.156 0.042 0.494 0.216 0.067 9 0.33 0.152 0.041 0.48 0.209 0.064 10 0.312 0.148 0.04 0.47 0.204 0.062 11 0.303 0.139 0.038 0.44 0.192 0.059 12 0.297 0.138 0.037 0.438 0.191 0.059 13 0.295 0.137 0.037 0.435 0.191 0.059 14 0.291 0.134 0.036 0.408 0.177 0.054 15 0.255 0.118 0.032 0.398 0.173 0.054 16 0.252 0.116 0.031 0.386 0.167 0.051 17 0.251 0.116 0.031 0.381 0.166 0.051 18 0.251 0.115 0.031 0.369 0.161 0.05 19 0.249 0.115 0.031 0.36 0.156 0.047 20 0.242 0.111 0.03 0.356 0.154 0.047 21 0.24 0.111 0.03 0.329 0.145 0.046 22 0.209 0.097 0.026 0.325 0.141 0.043

For Unit 1 or 2, lime injection is projected to reduce the visibility impact at MACA from 1.285 dv to 0.606 dv (2003). A wet ESP is projected to further reduce the impact to 0.166 dv. For Unit 3, lime injection is projected to reduce the visibility impact at MACA from 1.842 dv to 0.836 dv (2003). A wet ESP is proj ected to further reduce the impact to 0.264 dv.15 For Unit 1 or 2, lime injection is projected to reduce the visibility impact at MING from 0.251 dv to 0.116 dv (2002). A wet ESP is projected to further reduce the impact to 0.031 dv. For Unit 3, lime injection is projected to reduce the visibility impact at MING from 0.381 dv to 0.166 dv (2002). A wet ESP is proj ected to further reduce the impact to 0.051 dv.16 

### IV. Conclusions

Both control options reduce visibility im pacts at MACA and MING. However, the excessive costs associated with wet ESPs, as well as the large volumes of water required, make that option infeasible as a basis fo r BART. Although lime injection is less expensive, the cost effectiveness results as sociated with that option are too high, making the technology unacceptable as a basis for BA RT. As a result, TVA proposes that no additional control be required under the BART regulations.

As stated previously, TVA plans to install lime injection on all three units at PAF to mitigate stack opacity. These controls will be in place well before BART controls are required. So visibility impacts at MACA and MING will continue to be reduced, regardless of any decision related to BART.APPENDIX

COST OF COMPLIANCE DETAILS