November 19, 2008

Reply to

Attn Of: OEA-095

MEMORANDUM

SUBJECT: Comments on the ODEQ BART Report for the Boardman Power Plant, 

Updated November 7, 2008

FROM: Paul Boys, P.E.

Environmental Engineer, ESU, OEA

TO: Keith Rose, Environmental Scientist

State and Tribal Air Programs Unit, OAWT

As you requested, I have reviewed the BART Report for the Boardman Power 

Plant which was updated by ODEQ on November 7, 2008. ODEQ made a number 

of changes to the August 20, 2008 draft report that addressed some of the 

comments we had on the draft report. However, I have several comments on the 

November 7, 2008 update which are listed below. 

1. Page 13, Table 10. The baseline control effectiveness values appear to be 

rounded to two decimal points from the values given in the PGE BART 

analysis. For example, the baseline control effectiveness for NOx in the PGE 

BART analysis was 0.426 lb/mmBtu heat input whereas the value shown in 

Table 10 is 0.43. Similarly, the control effectiveness value for SO2 in the PGE 

BART analysis was 0.614 lb/mmBtu heat input whereas the value shown in 

Table 10 is 0.61. While this is not an issue for general comparison purposes, 

it does make a difference when making calculations. I suggest using all three 

digits to the right of the decimal point for the baseline control effectiveness 

values.

2. Page 19. ODEQ has decided to use the PGE cost estimates for the control 

technology alternatives rather than the ERG cost estimates. In the first 

sentence on page 19 the report states that “....PGE included an additional 

$40 million dollars for boiler modifications needed to reduce the temperature 

of the flue gases to the range required by the SCR.” The modifications 

include replacing the existing economizer section of the boiler with a larger 
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one. Will this boiler modification result in an improvement in the thermal 

efficiency of the boiler system? If it does, has the benefit of higher power 

generation per unit of coal burned been factored into the cost effectiveness 

calculations? If the modification does not improve the thermal efficiency of 

the boiler system, then it should be stated in the report so that this question 

will be answered for the reader.

3. Page 19, Table 15. I was not able to reproduce the cost effectiveness values 

shown in column 6 of Table 15 for the NOx control technology options. It 

appears that the cost effectiveness value should be the annual cost value 

(column 5) divided by the emission reduction value (column 3). The cost 

effectiveness values for the SO2 options can be reproduced by the calculation 

described above. If the cost effectiveness values are not correct, then the 

incremental cost effectiveness values may also be incorrect. Secondly, the 

units for the cost effectiveness and incremental cost effectiveness should be 

“$/ton” rather than “$/ton/yr” as shown in the headings for columns 6 and 7.

4. Page 20, Table 16. The baseline emissions for SO2 are not shown in Table 

16 (baseline NOx emissions are shown). The PGE BART report indicates that 

baseline SO2 emissions are 14,902 tons per year. However, using the value

of 14,902 tons per year and subtracting the annual emissions of 3643 tons 

per year associated with the SDFGD control option (from Table 16) does not 

give the emission reduction value of 11,988 tons/yr shown in Table 15. 

5. Page 23. In the first sentence of the second paragraph of the Cost-Benefit 

Analysis section, the units of cost effectiveness are shown as “$/ton/yr” rather 

than simply “$/ton.”

6. Page 23. In the third paragraph of the Cost-Benefit Analysis section, I could 

not reproduce the “3 to 8 times as much” factors using the capital cost values 

shown in Table 15. For example, the capital cost for LNB/MOFA from Table 

15 is $32.7 million and the capital cost for SCR is $190.9 million. The capital 

cost ratio between these control options is $190.9/$32.7 = 5.8 (round to 6). 

Likewise, the capital cost ratio between SCR and LNB/MOFA/SNCR is 

$190.9/$50.1 = 3.8 (round to 4). Since the incremental cost effectiveness 

values in Table 15 may be incorrect (see comment 3 above), the values 

shown in this section (page 23) may also need to be changed.

7. Page 29. In the first bullet under the item “Selective catalytic reduction is not 

recommended within the 2014 timeframe ....” the report states that “there is 

only a 27% improvement in visibility impacts.” I was not able to determine 

how that value was derived. The actual calculation should be included or a 

reference to a specific table should be added with a clear description of what 

values from the table were used to derive the 27% improvement in visibility 

impacts.
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8. Page 30, Table 25. The proposed BART emission limits in Table 25 should 

be expressed with a zero as the last digit so that the regulated source is not 

inadvertently allowed a higher limit than intended when rounding of emission 

test results is taken into account. For example, using the agency 

recommended rounding protocol, an emission test value of 0.125 would be 

rounded to 0.12 (since the digit “2” is an even number) for comparison with an 

emission limit of 0.12 (the proposed SO2 BART emission limit). This situation 

would allow the regulated source to have an emission test result 4% greater 

than the intended emission limit and still be viewed as in compliance. 

However, if the emission standard was written as 0.120, then an emission test 

result of 0.125 would clearly exceed the emission limit.

If you have any questions about these comments, please call me at 3-1567. 

cc. John Keenan, OCE

Keven McDermott, OEA