Balancing Authority Area Transmission Service Cost Estimates No GF WAPA 25 MW Generator Location Cost (in Millions of dollars) South of Great Falls $0 See footnote 1 on the next page North of Great Falls $8.75 East of Billings $25 Bozeman-Billings $12.5 Missoula-Butte WAPA Unknown So GF B-M E Bil Boz-Bil

Transmission Cost Attributable To 25 MW Project 25 MW Generator Location Full/Share (Full-CREP Triggers upgrade, Share-CREP shares in cost for upgrade) Cost (in Millions of dollars) Total Potential Cost (in Millions of dollars) Comments South of Great Falls Full $0 - $14.25 $01 No known congestion at this time with the current TSR queue. If needed, CREP will reconductor the line they are connected to in the SOGF area. North of Great Falls $8.75 If needed, CREP will reconductor the line they are connected to in the NOGF area. East of Billings $10 - $25 $25 If needed, CREP will reconductor the line in the Billings area. Bozeman-Billings $10 - $12.5 $12.50 If needed, CREP will reconductor the line in the Bozeman - Billings area. Missoula-Butte N/A $0 At this time, no transmission congestion has been identified and it is assumed that there is capacity on the lines to accommodate 25 MW. WAPA NE MT Unknown WAPA interconnection, balancing and regulation reserves, and transmission service costs are unknown. 1. Assumes the project is injecting its power a the Great Falls 230 Switch Yare. Should a project connect on one of 100 kV lines in the south of Great Falls transmission system, there is a likelihood that the 100 kV would need to be reconductored.