Open SeasonOpen SeasonMT to IdahoMT to Idaho

Calendar of EventsCalendar of EventsPosted on NWE OASIS September 30, 2004Posted on NWE OASIS September 30, 2004

(Slide 8 updated 2/28/05)(Slide 8 updated 2/28/05)

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Calendar of Events SummaryCalendar of Events Summary

October 1 – 31, 2004October 1 – 31, 2004 Phase 1 – Expression of Interest (EOI)Phase 1 – Expression of Interest (EOI)NWE evaluation of EOI: through mid NWE evaluation of EOI: through mid November; NWE to announce final November; NWE to announce final dates for Open Seasondates for Open Season

December 1 – 31, 2004December 1 – 31, 2004 Phase 2: Expected Open Season Phase 2: Expected Open Season dates: (Period that Transmission dates: (Period that Transmission Requests may be placed in the Requests may be placed in the QUEUE)QUEUE)

System Impact Studies on Open Season System Impact Studies on Open Season Capacity: at least 60 days following Capacity: at least 60 days following 12/31 depending on complexity12/31 depending on complexity

30 day Participant review period before 30 day Participant review period before NWE issues Facilities Study NWE issues Facilities Study AgreementsAgreements

Post December 31, Post December 31, 20042004

Phase 3: Facilities Study ProcessPhase 3: Facilities Study ProcessInterested Participants execute Interested Participants execute Facilities StudiesFacilities Studies

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NorthWestern’s Open Season ProcessNorthWestern’s Open Season Process

October 1 – 31, 2004October 1 – 31, 2004• Phase 1 – Expression of Interest (EOI)Phase 1 – Expression of Interest (EOI)

• Opportunity for generators/suppliers/load serving Opportunity for generators/suppliers/load serving entities to come together to help NorthWestern entities to come together to help NorthWestern define the market for transmission capacitydefine the market for transmission capacity

• NorthWestern will use EOI to determine if sufficient NorthWestern will use EOI to determine if sufficient interest to continue with Open Seasoninterest to continue with Open Season

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Phase 1 – Expression of Interest (EOI)Phase 1 – Expression of Interest (EOI)

• Interested parties to respond with:Interested parties to respond with: Capacity requested – 25 MW blocksCapacity requested – 25 MW blocks Direction of capacity requestDirection of capacity request Start date for capacity needsStart date for capacity needs Term of agreement for capacity (minimum term Term of agreement for capacity (minimum term

requirement)requirement) NorthWestern Energy EOI forms posted on OASISNorthWestern Energy EOI forms posted on OASIS

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Phase Two – Capacity Open Season “Preview” PeriodPhase Two – Capacity Open Season “Preview” Period

December 1 – 31, 2004December 1 – 31, 2004• Phase 2 – Open Season PreviewPhase 2 – Open Season Preview

• NorthWestern evaluates expressions of interest NorthWestern evaluates expressions of interest to determine most likely capacity addition(s)to determine most likely capacity addition(s)

• Mid-November 2004 – NorthWestern will post Mid-November 2004 – NorthWestern will post on OASIS the start and end dates to accept on OASIS the start and end dates to accept transmission service requests that will qualify transmission service requests that will qualify for the open season processfor the open season process

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Open Season ElementsOpen Season Elements

• Open Season is for Transmission Service Requests Open Season is for Transmission Service Requests with MT-SW (BOBR) as POR or POD with MT-SW (BOBR) as POR or POD ONLYONLY and for and for NEWNEW (not existing) capacity(not existing) capacity

• Same process for making Transmission Service Request Same process for making Transmission Service Request (TSR) as described in Section 17 of NorthWestern’s Open (TSR) as described in Section 17 of NorthWestern’s Open Access Transmission Tariff with these important Access Transmission Tariff with these important modifications:modifications:1.1. Completed Application for Transmission Service will Completed Application for Transmission Service will

temporarily be considered complete without the deposit of temporarily be considered complete without the deposit of approximately one month’s transmission service (OATT approximately one month’s transmission service (OATT section 17.3); the deposit will be section 17.3); the deposit will be DELAYEDDELAYED

2.2. System ImpactSystem Impact Study and associated study fee will be waived Study and associated study fee will be waived (NorthWestern will absorb cost of System Impact Studies)(NorthWestern will absorb cost of System Impact Studies)

As always, date/time stamped OASIS Transmission Service As always, date/time stamped OASIS Transmission Service Request will determine customer’s position in Transmission Request will determine customer’s position in Transmission Service QUEUEService QUEUE

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Open Season – Current CustomersOpen Season – Current Customers

• Current transmission customers with completed Current transmission customers with completed applications for new capacity requests for applications for new capacity requests for transmission service on MT-SW path will be transmission service on MT-SW path will be deemed to be part of Open Season (with QUEUE deemed to be part of Open Season (with QUEUE positions already established with reservation on positions already established with reservation on OASIS)OASIS)

• NorthWestern will work with these current NorthWestern will work with these current customers on treatment of deposits and study customers on treatment of deposits and study feesfees

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Open Season Elements – System Impact Study ResultsOpen Season Elements – System Impact Study Results

• Upon Open Season capacity request date closing, Upon Open Season capacity request date closing, NorthWestern will require approximately a 60-90 NorthWestern will require approximately a 60-90 day period to evaluate total transmission requests day period to evaluate total transmission requests and physical options to serve such requestsand physical options to serve such requests

• Results of study work will be provided to each Results of study work will be provided to each Open Season Participant and posted on Open Season Participant and posted on NorthWestern’s OASISNorthWestern’s OASIS

• Participants will be given 30 days to review results Participants will be given 30 days to review results of studies and then will be provided a Facilities of studies and then will be provided a Facilities Study Agreement by NorthWestern to execute in Study Agreement by NorthWestern to execute in order to continueorder to continue

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Phase 3 – Facilities StudyPhase 3 – Facilities Study

• Facilities Study Agreement must be executed and Facilities Study Agreement must be executed and returned to NorthWestern within 15 business days returned to NorthWestern within 15 business days together with Facilities Study Fee AND together with Facilities Study Fee AND DepositDeposit approximating one month’s Transmission Service approximating one month’s Transmission Service (at this point, each Open Season Participant has (at this point, each Open Season Participant has returned to normal Transmission Service Request returned to normal Transmission Service Request Procedures)Procedures)

• Failure to comply with above will result in OASIS Failure to comply with above will result in OASIS reservation deemed withdrawnreservation deemed withdrawn