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Date: September 9, 2011 Subject: Confirmation of Operation of Air Pollution Control Devices (APCD s ) for the Top 10

Sources in the Coal

- fired Mercury (Hg) , Hydrogen Chloride (HCl) , and P articulate M atter (PM) Floors From: Jeffrey Cole (RTI International) To: Bill Maxwell

OAQPS/SPPD/ESG (D243

- 01) U.S. Environmental Protection Agency Research Triangle Park, NC 27711 **Introduction** The EPA WAM requested that RT I confirm what air pollution control devices (APCDs) were actually in operation on the top 10 sources during performance tests used in the coal

- fired MACT floor analysis for the Hg, HCl, and PM floors
. **Background** Through a review of early public comments, the WAM received indications that some APCD s that were listed as being installed on a given unit may not have been operating during the IC R performance stack testing . The commenter asserted that the EPA should review these control configurations for accuracy, and then instead of choosing the lowest reported emission rate for the new source MAC T standard, the EPA should choose the controlled source near the lowest emitting source that was actually controlled with the control configuration most likely to be placed on a newly built EGU
. The commenter believe d this approach makes the new MACT floor more realistic and achievable. To aide in this evaluation, RTI was requested to confirm the APCD s operating during the Hg, HCl, and PM ICR performance testing for the top 10 units in Hg, HCl and PM floors and make recommendations as to which top performer reflects the air pollution controls configuration most likely required to permit a new EGU. **Technical Approach for Coal** **- Fired Units**  RTI contacted the operators of the top 9 of the 131 units in the PM floor. The 10 th unit’s (San Juan, Unit 3) APCD s that were in operation during Part III ICR testing were confirmed b ased on the configuration listed in Part I of the ICR and the controls used during Part III testing were noted in the ERT files. For units in the top 10 of the 131 units in the HCl floor and in t he top 10 of the 40 units in the Hg floor, RTI determined the APCD s that were in operation during ICR testing by comparing the APCD configurations listed in Part I of the ICR with the controls used during Part III testing as noted in the ERT files. There was a change to unit

-ranking within PM floor datasets examined based on information submitted by operators since proposal . In the PM floor, the previous best unit tested, Bonanza Unit 1 , dropped out of the top 10 units in the floor upon incorporation of a c orrected submittal. This had the effect of shifting each unit in the list up one ranking and moving San Juan Unit 3 into the top ten for lowest PM emissions.2

Note that there was one unit in the top ten of the Hg floor units and two units in the top ten HCl floor units that were ranked based solely on Part II data. The controls that were in operation during the MACT floor performance tests were consistent with the controls listed in their Part I submissions . The Part I controls for those units are listed in Tables 2 and 3. In order to determine the range of control technologies that would be expected on a new EGU to comply with existing major source permitting requirements and to evaluate the impacts of these required control technologies on achievability of the MACT emission standards, a review of the RACT/BACT/LAER Clearinghouse was conducted for EGU’s permitted since January 1, 2006. This review indicated the following predominant technologies:

 Fabric filters were the predominant BACT for PM; twenty- seven of the twenty-nine sources were for permitted fabric filters, and two were permitted for ESPs.

 Fifty percent of the listed sources were permitted for dry scrubbers and fifty percent were permitted for wet scrubbers as BACT for SO2.

 For sulfuric acid mist (a primary constituent in condensable PM), the predominant BACT was dry sorbent injection either integral to the spray dryer absorber or upstream of a wet scrubber.

 SCRs were the predominant BACT for NOx control.

 Sorbent injection or activated carbon inj ection was predominant for control of mercury. Based on this review of the RACT/BACT/LAER Clearinghouse, the air pollution control configuration that would be expected on a new EGU permitted under the NSR program would be expected to have the following fou

r major components: 1. Either a fabric filter or a high efficiency ESP; 2. Either a wet or dry FGD system; 3. Activated carbon or other sorbent injection; 4. Selective Catalytic Reduction (SCR). **Summary of Findings**

 Table 1 shows the confirmed APCD s in operation during MACT floor total PM performance tests for the revised top 10 coal

- fired units.

 Table 2 the confirmed APCD s in operation during MACT floor HCl performance tests for the top 10 coal

- fired units
.  Table 3 shows the confirmed APCD s in operation during MACT f loor Hg performance tests for the top 10 coal

- fired units
.3

**Particulate Matter (PM)** In the proposed rule, the EPA chose to use Dunkirk Unit 1 (ORIS Code 2554) for the new source total PM input

-based floor (lb/MMBtu) and Bonanza Unit 1 (ORIS Code 7790) for the new source total PM output-based floor (lb/MWh). As stated above the Bonanza Unit 1 ’s original ranking was based on an erroneous submittal and, once corrected, it dropped out of the top 10 units in the total PM floor. Based on the comments received it i s clear that Dunkirk Unit 1’s control configuration (see highlighted row in Table 1) was different during the MACT floor performance tests than the control configuration reported in Part I of the ICR because no SNCR or dry sorbent injection system was operating during the ICR stack tests. Therefore, RT I does not recommend that either of these units continue to be considered for the new floors. In addition , we also believe that s etting a new MACT based on a unit with only a fabric filter would not be reflective of either the best available control technology (BACT) or 112(g) case

-by

-case MACT that would be required under existing maj or source preconstruction permitting programs: There are only two units within the top ten with the air pollution control configurations that are typical of the predominant BACT technologies: 1. Springerville Unit 4 deploys a dry FGD system. This source is equipped with an SCR, spray dryer absorb er, and a fabric filter
. 2. Havana Boiler 9 deploys a dry FGD system. This source is equipped with an ESP, SCR, ACI, dry scrubber, and a fabric filter. Because wet scrubbers are effective in removing PM larger than five microns from flue gas, ESPs followed by wet scrubbers can also approach the PM emission rates achievable by dry scrubbers with f abric filters as reflected by the presence of Roxboro Unit 2 in the top 10. These air pollution control strategies are driven by state mercury control emissions standards and national fine particulate ambient standards . Requirements to deploy these technologies can directly impact a source’s ability to meet the surrogate total PM limit due to the significant dust loading added to the flue gas by the controls. The layout of dust from these systems can be problematic during startups and shutdowns when the par ticulate control device may be bypassed (e.g., fabric filters) or when the PM control device may be below design temperatures (e.g., ESPs). Additionally, these control technologies can pose challenges during malfunctions (e.g., punctured bags ) as dust loads remain high while operators determine the location of the problem. For these reasons , RTI recommends selection of Havana Boiler 9 as the source within the top 10 for PM that reflects the air pollution controls typical for new EGUs because this source deploys both ACI and dry sorbent. **Acid Gases** The EPA chose to utilize Logan Unit 1 ’s (ORIS Code 10043) emission averages in the proposed rule for the new HCl floor. This still seems like a good choice, as it is equipped with an SCR, spray dryer ab sorber and a fabric filter, which are consistent with the predominant controls found in the RACT/BACT/LAER Clearinghouse. **Mercury** Finally, the EPA chose Nucla Unit 1 (ORIS Code 527) in the proposed r ule for the Hg floor because the two Spruance Genco Units (Gen 2 and 3, ORIS Code 54081) are an unusual furnace design that is likely atypical4

of future new EGU’s. Nucla Unit 1 still appears to be an appropriate choice, as it is equipped with an SCR, spray dryer absorb er and a fabric filter. These controls are consistent with the predominant controls found in the RACT/BACT/LAER Clearinghouse. However, in our review of comments, we have seen concerns that Nucla Unit 1 is not a good choice for a new floor unit because , in the commenter’s opinion, this unit has a “unique” fuel that cannot be reproduced and that yields emission rates that are unachievable by other sources
. Itis worth noting that Logan Unit 1 (ORIS Code 10043) achieved virtually the same Hg emission rate as Nucla Unit 1 during MACT floor performance testing
. Logan Unit 1 is a conventional, wall

- fired unit ( as compared to Nucla’s FBC) , and it is controlled with an SCR, spray dryer absorb er and a fabric filter. This unit would also be a good choice as a representative unit for newly constructed EGUs
.5 **Table 1 . The**  **Top 10 Units in the Total PM MACT Floor for Coal -** **fired EGUs**
ORIS code Plant Name Unit Number Unit Type Boiler T ype Boiler C ount Total Capacity MW e Total max heat

input ( MMBtu/hr ) Unit heat rate

(MMB tu/MW h ) Fuel type ( s ) APCD Controls listed at Proposal Confirmed APCD Controls 2554 Dunkirk Generating Plant 1 Conventional Boiler Tangential firing 1 85 922.2 10.85 subbituminous SNCR, DSI, FF FF 492 Martin Drake Unit 5
- Coal Conventional

Boiler Wa ll firing
- front firing 1 55 570 10.36 subbituminous FF, W FGD FF, W FGD 568 Bridgeport Station BHSEM U3OS3
- #2 Conventional

Boiler Tangential firing 1 403 4100 10.17 subbituminous ESP, ACI, FF ESP, ACI, FF 2712 Roxboro Steam Electric Plant Rox_Cfg _2c Conventional

Boiler Tangential firing 1 703 6893 9.81 bituminous SCR , ESP, W FGD SCR, ESP, WF GD 8223 Springerville 4 Conventional Boiler Wa ll firing
-

opposed firing 1 450 4200 9.33 bituminous SCR, DFGD, FF SCR, DFGD, FF 891 Havana Boiler 9 Conventional Boiler Wa ll firing
-

unspecified 1 481 5030 10.46 bituminous ESP, SCR , ACI, DFGD, FF ESP, SCR, ACI, FF 2554 Dunkirk Generating Plant 4 Conventional Boiler Tangential firing 1 195 1836 9.42 subbituminous SNCR, DSI, FF FF 7097 J K Spruce 1 Conventional Boiler Tangential firing 1 580 6361 10.97 bituminous FF, W FGD FF, W FGD 2324 Reid Gardner 1 Conventional Boiler Wa ll firing
- front firing 1 111 1215 10.95 bituminous FF, W FGD FF, W FGD 2451 San Juan Unit 3 Conventional Boiler Wa ll firing
-

opposed firing 1 544 5758 10.58 subbituminous FF, ACI, W FGD FF, ACI, W FGD
**Table 2 . Th**  **e Top 10 Units in the HCl MACT Floor for Coal -** **fired EGUs**
ORIS code Plant Name Unit Number Unit Type Boiler T ype Boiler C ount Total Capacity MW e Total max heat

input ( MMBtu/hr ) Unit heat rate

(MMB tu/MW h ) Fuel type ( s ) APCD Controls listed at Proposal Confirm ed APCD Controls 10043 Logan Generating Plant Unit1 Conventional Boiler Wa ll firing
-

opposed firing 1 241.7 2116 8.75 bituminous SCR, DFGD, FF SCR, DFGD, FF 54081 Spruance Genco, LLC GEN3 Conventional Boiler Stoker
- underfeed 2 57.4 750 13.07 bituminou s DFGD, FF DFGD, FF 54081 Spruance Genco, LLC GEN2 Conventional Boiler Stoker
- underfeed 2 57.4 750 13.07 bituminous DFGD, FF DFGD, FF 3130 Seward SEW
- 1 Fluidized bed firing Fluidized bed firing 2 585 6200 10.60 coal refuse (culm or gob) SNCR, FF SNCR, FF 3130 Seward SEW
-2 Fluidized bed firing Fluidized bed firing 2 585 6200 10.60 coal refuse (culm or gob) SNCR, FF SNCR, FF 52071 Sandow Station 5A Fluidized bed firing Fluidized bed firing 1 282.35 2960 10.48 lignite SNCR, ACI, DFGD, FF SNCR, ACI,

DFGD, FF 56224 TS Power Plant TSPower Conventional Boiler Wa ll firing
-

opposed firing 1 242 2112 8.73 subbituminous SCR, ACI, DFGD, FF SCR, ACI, DFGD, FF 3179 Hatfield's Ferry Power Station 001 Conventional Boiler Wa ll firing
-

opposed firing 1 590 5700 9.66 bituminous ESP, W FGD ESP, W FGD 52071 Sandow Station 5B Fluidized bed firing Fluidized bed firing 1 282.35 2960 10.48 lignite SNCR, ACI, DFGD, FF SNCR, ACI,

DFGD, FF 108 HOLCOMB SGU1 Conventional Boiler Wa ll firing
-

opposed firing 1 387 3389 8.76 subbit uminous DFGD, FF DFGD, FF6 **Table 3. The Top 10 Units in the Mercury MACT Floor for Coal -** **fired EGUs**
ORIS code Plant Name Unit Number Unit Type Boiler T ype Boiler C ount Total Capacity MW e Total max heat

input ( MMBtu/hr ) Unit heat rate

(MMB tu/MW h ) Fuel type ( s ) APCD Controls listed at Proposal Confirmed APCD Controls 54081 Spruance Genco, LLC GEN2 Conventional Boiler Stoker
- underfeed 2 57 750 13.07 bituminous DFGD, FF DFGD, FF 54081 Spruance Genco, LLC GEN3 Conventional Boiler Stoker
- underfeed 2 57 750 13 .07 bituminous DFGD, FF DFGD, FF 527 Nucla 001 Fluidized bed firing Fluidized bed firing 1 110 1032 9.38 bituminous FBC, SNCR, FF FBC, SNCR, FF 10043 Logan Generating Plant Unit1 Conventional Boiler Wa ll firing
-

opposed firing 1 242 2116 8.75 bituminous SCR, DFGD, FF SCR, DFGD, FF
3130 Seward SEW
- 1 Fluidized bed firing Fluidized bed firing 2 585 6200 10.60 coal refuse (culm or gob) SNCR, FF SNCR, FF

2527 AES Greenidge Unit 4 Conventional Boiler Tangential firing 1 112 1117 9.97 bituminous, petroleum co ke SCR, ACI, DFGD, FF SCR, ACI, DFGD, FF 54035 Roanoke Valley I Boiler 1 Conventional Boiler Wa ll firing
- front firing 1 182 1700 9.34 bituminous DFGD, FF DFGD, FF 2526 AES W estover, LLC 8 Conventional Boiler Tangential firing 1 86 875 10.17 bituminous SCR, DFGD, FF SCR, DFGD, FF
50976 Indiantown

Cogeneration, L.P. 001 Conventional Boiler Wa ll firing
-

opposed firing 1 361 3422 9.48 bituminous SCR, DFGD, FF SCR, DFGD, FF

50888 Northampton

Generating Company, L.P. GEN1 Fluidized bed firing Fluidized bed firing 1 121 1146 9.47 coal refuse (culm or gob) FBC, SNCR, FF FBC, SNCR, FF