Region 6 Comments on Domtar BART analysis 

8/29/13 

General Comments 

 ADEQ should provide the proposed SO2 and NOx BART emission limits shown in Table 1-1 in 

terms of lbs/MMBtu. 

 Section 2 of the BART report explains that a new baseline emission rate for SO2, NOx, and PM is 

proposed for Power Boiler 1 to reflect the change in emissions resulting from the installation of a 

wet ESP in 2007. ADEQ should also provide updated emissions information for Power Boiler 1 in 

support of the new baseline emission rates.

 ADEQ should provide calculations and fuel use data utilized in estimating the 24-hr maximum 

emission rates for the revised baseline period for Power Boiler 1. 

SO2/NOx BART Emission Limits 

 The SO2 BART analysis (section 5.1) states “Because No. 1 Power Boiler does not contribute to 

visibility impairment greater than 0.5 Δdv at any of the Class I areas, and moreover does not 

contribute to visibility impairment on even a single day, Domtar proposes no additional add-on 

controls...” This is not an appropriate justification for not conducting a BART analysis for SO2. 

The 0.5 dv threshold applies only to the determination of whether the facility, considering all BART 

eligible units, is subject to BART. If the total impact from all BART eligible units at the facility is 

greater than 0.5 dv, then each unit must be evaluated for BART. In addition, we also note that the 

preamble of the RH rule explains that “Failing to consider less-than-perceptible contributions to 

visibility impairment would ignore the CAA’s intent to have BART requirements apply to sources 

that contribute to, as well as cause, such impairment” (70 FR 39104, at 39129). Given that sources 

are subject to BART based on a contribution threshold of 0.5 dv, it would be inconsistent to 

automatically rule out additional controls where the improvement in visibility may be less than 1.0 

dv or even less than 0.5 dv. A perceptible visibility improvement is not a requirement of the BART 

determination because visibility improvements that are not perceptible may still be determined to be 

significant. 

We note that in some cases, states may adopt a more streamlined approach to making BART 

determinations where appropriate. For example, a State need not undertake an exhaustive analysis 

where it is clear that controls would be costly and any improvements in visibility resulting from 

reductions in emissions would be negligible (70 FR 39104, at 39116). An examination of the 

baseline visibility results for Boiler 1 indicates that visibility impacts on the high impact days are 

primarily due to nitrate. Therefore, it is likely that further reductions in SO2 emissions would not be 

cost-effective in terms of visibility benefit unless those controls were extremely inexpensive. After 

taking the above into consideration, if ADEQ has found it is still appropriate to take the streamlined 

approach to making a BART determination for SO2, it should provide an appropriate justification 

that satisfies the RH rule and is consistent with the BART guidelines. 
 The BART analysis dismisses the control options evaluated for NOx BART for Power Boiler 1 

because “The No. 1 Power Boiler does not contribute to visibility impairment greater than 0.5 dv nor 

any single day of impairment [greater than 0.5 dv] at any of the Class I areas ... therefore, the 

considered control options provide no improvement in visibility impairment” (section 6.3). As 

discussed in our comment above for SO2 BART, given that sources are subject to BART based on a 

contribution threshold of 0.5 dv combined for all BART eligible units at the facility, it would be 

inconsistent to rule out additional controls on the basis that the improvement in visibility is less than 

0.5 dv. Therefore, we recommend that the above quoted language be revised. Additionally, we note 

that we have remaining concerns with the evaluation of the NOx control scenarios, as detailed in 

comments below. 

 The maximum 24-hr emission rate for Power Boiler 1 is estimated as 17.5 lb/hr for SO2 and 121.2 

lb/hr NOx. However, an emission limit of 21 lb/hr for SO2 and 145 lb/hr for NOx demonstrated 

based on a monthly and 12-month rolling basis are proposed as BART. Given that compliance with 

the SO2 and NOx BART emission limits is proposed on a monthly basis, we do not believe a 20% 

compliance margin above the 24-hr maximum emission rates is necessary. A justification, including 

any supporting emissions data or other information, explaining the need for a 20% compliance 

margin should be provided. 

 The Lundberg report on emissions controls for Power Boiler 2 states that “With regard to the BART 

regulation, as discussed, there has been no guidance from the regulatory authorities. Given this, we 

have selected 90% SO2 reduction as a common-sense approach to the situation... if higher removal 

rates are required the equipment offered can probably be re-designed without a major impact on the 

project.” We disagree that there has been no guidance from EPA regarding what level of control 

should be evaluated for BART. The RH rule requires that in analyzing controls for BART, the most 

stringent emission control level that the technology is capable of achieving must be taken into 

account (70 FR 39166). Based on the above statement made in the Lundberg report, it does not 

appear this requirement has been met in the SO2 BART analysis. Additionally, the SO2 BART 

analysis states that consideration of any further control using an add-on wet scrubber/WESP beyond 

what was evaluated and selected as BART is unreasonable. This appears to contradict the statement 

made in the Lundberg report concerning the feasibility of re-designing the equipment to achieve a 

higher removal rate if needed. The potential for greater removal efficiency may result in greater 

visibility improvement than what is currently expected. ADEQ should ensure that the requirement to 

evaluate the most stringent level of SO2 control the add-on wet scrubber/WESP is capable of 

achieving has been met. 

 In analyzing SO2 BART for Power Boiler 2, Domtar states that Lundberg evaluated upgrades to the 

existing scrubber but that it has been unable to quantify any potential additional control. After 

discarding this potential BART control option from further consideration with little explanation, 

however, Domtar subsequently determined that the SO2 BART control it did evaluate – an 

additional add-on scrubber/wet ESP - is not BART. In light of this, Domtar should re-evaluate the 
scrubber upgrade option it rejected and provide any reports prepared by Lundberg or others on the 

scrubber upgrade option. 

SO2 Cost Analysis 

 One of the reasons Domtar cites for rejecting the scrubber/wet ESP for SO2 BART for Power Boiler 

2 is the cost for additional energy and water use. However, this appears to conflict with the 

Lundberg report which states, “there would be no additional process water requirement because 

spent water from the spray scrubber/wet ESP could ‘feed forward’ to the scrubber system as makeup.” If this statement from the Lundberg report is incorrect and water cost/availability is really being 

used as a reason for rejecting the scrubber/wet ESP as SO2 BART, the BART analysis should 

provide additional information on the amount of water this scrubber/WESP will use over and above 

the plant’s process water and the cost of that water. 

 ADEQ should provide supporting information for some of the line items in the scrubber/wet ESP 

cost analysis for Power Boiler 2: 

o Detailed documentation should be provided for the “Costs to Retrofit” figure of $13,175,000, 

referenced as footnote 11 in Appendix B, which states, “Domtar's engineers estimate that 

PEC accounts for only approximately 40% of the total investment to place a new WESP into 

service.” 

o Documentation should be provided for the wastewater treatment figure of $6,092,425 and it 

should specifically be documented how much of that treatment would be due to the addition 

of the scrubber/wet ESP in relation to the rest of the plant. 

o Documentation should be provided for the annual sorbent caustic usage of $2,300,000. It 

should specifically be documented how much of that sorbent caustic is necessary due to the 

addition of the scrubber/wet ESP over and above that supplied by the existing process 

stream. 

o The cost analysis bases its capital recovery factor (CRF) on a 20 year life based on a 

reference from the CCM. The section of the CCM referenced states that “For ESPs, the 

system lifetime varies from 5 to 40 years, with 20 years being typical” (Section 6, Chapter 3 

of the CCM). Since Domtar has obtained a quote from the vendor, documentation of the 

vendor’s estimate/guarantee of the expected lifetime of the equipment should be provided 

and ADEQ should ensure that the CRF is based on the vendor’s estimate/guarantee. 

o The need for an annual wastewater treatment cost of over $6M should be documented. In 

particular, it should be explained how much of this treatment cost is due solely to the 

addition of the scrubber/wet ESP over and above the treatment needed for its existing process 

wastewater streams. This should include documentation of the additional wastewater volume 

generated due to the scrubber/wet ESP. 

o A fully working spreadsheet of the cost calculations should be provided. 
NOx BART 

 Regarding the evaluation of SNCR for Power Boilers 1 and 2, ADEQ should ensure that Domtar 

provides any information it received from FuelTech that was used to analyze the potential 

control efficiency, cost, reagent usage, and any other information that is relevant to a BART 

determination. For instance, Figure 6-1 appears to have been copied from a report. This and all 

other reports relevant to the NOx BART determination should be provided. Domtar should 

justify any assumptions regarding the control scenarios it assumed and evaluated for SNCR and 

why those control scenarios are different for Power Boilers 1 and 2. The RH rule requires that in 

analyzing controls for BART, the most stringent emission control level that the technology is 

capable of achieving must be taken into account (70 FR 39166). Therefore, ADEQ should ensure 

that Domtar demonstrates that it has evaluated the most stringent level of NOx control SNCR is 

capable of providing for Power Boilers 1 and 2. 

 For Power Boiler 2, Domtar proposes a 6% decrease in NOx from the original BART 

determination (30% reduction using LNB). Domtar also states that this level of control (36%) is 

potentially achievable with SNCR. However, SNCR was evaluated at 35% control. It is unclear 

how this level of reduction was determined based on an evaluation of the five-factors and 

evaluation of the control efficiency of the available control technologies. It is also unclear if the 

combination of LNB and SNCR was examined. 

 Methane de-NOx (MdN) is modeled at 50% control efficiency for Power Boiler 2 and is 

modeled to reduce visibility impacts at Caney Creek by approximately 0.3 dv. However there is 

no discussion of MdN feasibility, anticipated control efficiency, or cost. It is unclear how MdN 

was considered as part of the 5-factor analysis. Domtar’s previous analysis, prepared in 

2006/2007 and submitted with the Arkansas Regional Haze SIP in 2008 evaluated MdN and 

determined that it was not cost-effective but did not perform a visibility analysis on this control 

option. Similarly, no cost or emissions data are provided for LNB in the revised draft BART 

analysis, even though the revised draft BART reports states the source may install LNB to meet 

the NOx BART emission limit proposed for Power Boiler 2. ADEQ must ensure that the revised 

Domtar BART analysis it submits as part of the Regional Haze SIP revision includes the 

complete evaluation of all NOx controls, including MdN and LNB. If in its Regional Haze SIP 

revision, ADEQ decides to rely on or use any parts of the 2006/2007 Domtar BART analysis, it 

must ensure that the information (especially any information on costs, control efficiency, and 

availability of controls) continues to be up to date and that those portions of the 2006/2007 

BART analysis are re-submitted and included in the Regional Haze SIP revision package. If 

ADEQ is indeed relying on the cost information for MdN provided in the 2006/2007 Domtar 

BART analysis, we believe the cost of that control for Power Boiler 2 ($4,259/NOx ton reduced) 

is not unreasonable given the significant visibility improvement expected at Caney Creek. The 

BART analysis should include a discussion of why MdN was not selected for NOx BART for 

Power Boiler 2 after all five factors were taken into consideration. 

NOx Cost Analysis 
 Domtar should provide the following regarding the cost analyses for SNCR: 

o Domtar should assume a 30 year operating life. 

o Domtar should provide documentation for the annual maintenance fee of $310,000, and the 

fixed (indirect) costs of $771,895. 

o There are a number of factors that are listed in the SNCR cost evaluations that are not 

explained. For instance, Domtar should explain why the bark cost and the ash disposal cost, 

the 2011 and 1998 cost indices, and the bark HHV are relevant to the SNCR cost estimations. 

o Domtar should explain how the equation for the direct capital costs was derived, including all 

constants and parameters. 

o Domtar should justify why a project contingency of 15% is needed for this project. Why is a 

process contingency also specified and how is that calculated? 

o Domtar should explain the following costs, what they cover, and how they are calculated: 

 preproduction cost, inventory capital, general facilities, engineering and home office fees. 

[Domtar cites the CCM as a reference for SNCR costs, but these fees should still be justified 

as real costs]. 

o Domtar should provide a more accurate documentation for the urea cost. The link provided 

in the notes to the SNCR cost table in Appendix B refers to a World Bank quote for a bulk 

spot FOB price for delivery to the Black Sea area and Eastern Europe. In addition, there 

appears to be a huge spike in price in 2008 that does not appear to be representative of the 

general price trend. 

PM BART 

 We agree with the general approach of relying on the MACT PM standard to satisfy the PM 

BART requirement for Power Boiler 2. However, to be able to take this streamlined approach, 

the current MACT PM limit must be used to satisfy PM BART. The BART guidelines provide 

that for “For VOC and PM sources subject to MACT standards, sates may streamline the 

analysis by including a discussion of the MACT controls and whether any major new 

technologies have been developed subsequent to the MACT standards... Unless there are new 

technologies subsequent to the MACT standards which would lead to cost-effective increases in 

the level of control, you may rely on the MACT standards for purposes of BART” (Appendix Y 

to Part 51, section IV.C). Based on this language, it is clearly not acceptable to take the 

streamlined approach by using an outdated MACT PM emission limit to satisfy PM BART. On 

January 31, 2013, EPA took final action on the proposed reconsideration of certain issues related 

to the MACT emission standards, promulgating a final MACT PM limit of 0.04 lb/MMBtu for 

existing coal-burning boilers and process heaters (see 78 FR 7138). However, Domtar proposes 
to take the streamlined approach for PM BART by accepting the previous MACT PM emission 

limit of 0.07 lb/MMBtu, which was promulgated in 2004 and has since been vacated and 

remanded by the DC Circuit Court. In the Arkansas RH SIP submitted in 2008, it was 

appropriate for the state to rely on the 0.07 lb/MMBtu MACT PM emission limit for Power 

Boiler 1 because the effective date of the DC Circuit’s vacatur of the 2004 MACT rule was after 

the close of the public notice and comment period for Arkansas’s proposed RH rule. However, 

ADEQ must now address PM BART for Power Boiler 2 in a RH SIP revision that addresses the 

portions of the 2008 RH SIP disapproved by EPA, and it must therefore ensure that if the 

streamlined approach is taken for PM for Power Boiler 2, the current MACT PM limit is used to 

satisfy PM BART. Additionally, ADEQ should ensure that the BART analysis includes a 

discussion of the MACT controls and whether any major new technologies have been developed 

subsequent to the final MACT PM standard issued in January 2013.