TEMPORARY OPERATING INSTRUCTION No. 15-184 15-00083 15-00421 1-08961617 15-00077 1-08191048 O.O. 15-00086 MISO No 1-08968505 File No. 240801 15-00098 1-08895999 15-00363 1-08968500 15-00084 1-08969572 15-08673 115 kV Line SW2 (Seven Sisters – Whiteshell) 115 kV Line CR4 (Parkdale – Rosser) Abnormal Seven Sisters Unit 2 and 3 Operating Condition: 115 kV Line SR3 (Seven Sisters – McArthur Falls) 115 kV Line SW3 (Seven Sisters – Whiteshell) 230 kV Line D16R (Dorsey – LaVerendrye) 2015-09-15 from 0800 to 2015-09-15 at 0830 CDT Effective Dates: (2015-09-15 from 0800 to 2015-09-15 at 0830 EST) Standing Guide Reference: MHEB Study as per D. Hartwich

Description of Work: SW2 – Seven Sisters Unit 3 protection upgrade. CR4 – Rosser and Parkdale various maintenance. SS Unit 2 – protection testing, SS Unit 3 protection upgrades. SR3/SW3 – protection testing. D16R – Momentary switching for Rosser Bank 1 outage.

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Special Instructions Export: If RTCA indicates that the loss of SW1 will cause overloads on SW4 to MHEB Operator: and vice versa, transfer to IESO may need to be curtailed.

Import: If RTCA indicates that the loss of ST5 or ST6 or F3M will cause overloads on WT34, transfer from IESO may need to be curtailed.

MISO North RC MH_ONT_E (Export) SOL = 90 MW Notes: MH_ONT_W (Import) SOL = 239 MW

Special Instructions: TOI Extensions - This TOI may be extended until 23:59, by performing the following steps.

a) Verify system conditions to confirm there are no additional tie line facilities outages, or new internal MH outages. b) Review RTCA to confirm there are no new contingencies. c) Contact MISO to confirm there are no new outages, if there are no new outages provide notice to MISO that MH is extending the TOI. d) Extend the outage in COLA e) Update TLAP outage table f) Provide notice to affected balancing authorities

Prepared By: S. Brooks Date: 2015 09 09

Copies to: SOSS, System Control Centre NSSS, System Control Centre 2 TEMPORARY OPERATING INSTRUCTION No. 15-184 GSSS, System Control Centre GSO, System Control Centre Operating Order Ontario IESO MISO – St. Paul MHEB OASIS File 240801

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