November 1 9 , 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, E S U, O EA

TO: Keith Rose, Environmental Scient ist

State and Tribal Air Programs Unit, OA WT

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 address ed 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 th e values given in the PGE BART analysis. For example, the baseline control effectiveness for NO

x 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 SO 2 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 larg er2

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 NO

x control technology options. It

appear s 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 SO 2 options ca n 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 SO 2 are not shown in Table 16 (baseline NO

x emissions are shown). The PGE BART report indicates that

baseline SO 2 emissi ons are 14

, 902 tons per year. However, using th e 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 A nalysis 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 capit al 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 incorrec t (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 wer e used to derive the 27% improvement in visibility impacts.3

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 i ntended 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

emis sion limit of 0.12 (the proposed SO 2 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 th ese comments , please call me at 3

- 1567.

cc. John Keenan , O CE Keven McDermott, OEA