ANNUAL SULFUR DIOXIDE EMISSION REPORT

ANNUAL SULFUR DIOXIDE (SO 2 ) EMISSION REPORT PacifiCorp Company ID - 948 Huntington Power Plant Site ID - 10238

SUMMARY OF ANNUAL SO 2EMISSIONS SUBMITTED TO EPA FOR ACID RAIN PROGRAM Component Company ID ID Component 1999 2006 Actuals Changes Adjusted 4032 01 dry bottom tangentially fired utility boiler 2,030.4 3,196.2 2878.76 317.5 3,196.2 4033/4032 01 dry bottom tangentially fired utility bo iler-oil NA 0 0.74 0.0 0.74 4034 02 dry bottom tangentially fired utility boiler 11,870.2 17,128.8 14514.73 2,614.0 17,128.8 4035/4034 02 dry bottom tangentially fired utility bo iler-oil NA 0 1.17 0.0 1.17 13720 15 Auxiliary Steam Boiler for Unit #1 0.07 0.00 0 0.0 0 13721 16 Auxiliary Steam Boiler for Unit #2 0.01 0.00 0 0.0 0 13730 12 Emergency generator diesel engine for Unit # 1 0.01 0.01 0.197 0.0 0.197 13731 13 Emergency generator diesel engine for Unit # 2 0.01 0.01 0.14 0.0 0.14 13732 14 Emergency fire pump diesel engine 0.08 0.07 0.072 0.0 0.072 Mobile 6.631 0.0 6.631 Total 17402.44 2931.517 20333.96 CHANGES IN MONITORING OR CALCULATION METHODS Component Company ID ID 4032 01 dry bottom tangentially fired utility boiler

Component Company ID ID 4033 01

Component Company ID ID Component 4034 02

Adjustment of 2006 emissions to be comparable to 19 99 emissions: The 2006 SO2 Emissions were adjusted using method 2of the Sulfur Dioxide Milestone Inventory Requirements and Instructions. The Flow AdjustmentFactor calculated was 1.18. Explanation of Change: Changed from Method 2 in 1999 to Method 2FH for 200 6. dry bottom tangentially fired utility boiler Adjustment of 2006 emissions to be comparable to 19 99 emissions: Component dry bottom tangentially fired utility boiler-diesel Explanation of Change: NA, emissions are included in the CEM value for thi s Unit. Adjustment of 2006 emissions to be comparable to 19 99 emissions: The 2006 SO2 Emissions were adjusted using method 2of the Sulfur Dioxide Milestone Inventory Requirements and Instructions. The Flow AdjustmentFactor calculated was 1.11. Component Explanation of Change: Changed from Method 2 in 1999 to Method 2F for 2006

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Component Company ID ID 4035 02

Component Company ID ID 13720 15

Adjustment of 2006 emissions to be comparable to 19 99 emissions: Component Auxiliary Steam Boiler for Unit #1 Explanation of Change: This unit did not operate in 2006 Adjustment of 2006 emissions to be comparable to 19 99 emissions: NA, emissions are included in the CEM value for thi s Unit. Component dry bottom tangentially fired utility boiler Explanation of Change:

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Component Company ID ID Component 13721 16

Component Company ID ID 13730 12

Component Company ID ID Component 13731 13

Component Company ID ID 13732 14

Adjustment of 2006 emissions to be comparable to 19 99 emissions: Emergency fire pump diesel engine Explanation of Change: No changes, all values were calculated using AP-42 factors. Component Adjustment of 2006 emissions to be comparable to 19 99 emissions: Emergency generator diesel engine for Unit #2 Explanation of Change: No changes, all values were calculated using AP-42 factors. Adjustment of 2006 emissions to be comparable to 19 99 emissions: No changes, all values were calculated using AP-42 factors. Component Emergency generator diesel engine for Unit #1 Explanation of Change: Adjustment of 2006 emissions to be comparable to 19 99 emissions: Auxiliary Steam Boiler for Unit #2 Explanation of Change: This unit did not operate in 2006

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