Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2020-02-01

The table below contains the significant transmission outages submitted as tentative to the AESO.
These Outages have not yet necessarily been approved, but are listed for awareness and coordination purposes.
An Outage has been considered significant for this table if it meets any one (1) or more of the following criteria:
  1. it affects a transmission facility operating at two hundred and forty (240) kV or greater;
  2. it affects an intertie;
  3. it affects an element connecting facilities owned by two (2) or more different legal owners of transmission facilities;
  4. it affects an element that connects a generating unit or an aggregated generating facility to the interconnected electric system;
  5. it requires the ISO to issue a dispatch or directive for generation in order to facilitate the planned outage;
  6. it affects a cutplane limit;
  7. it limits or reduces the operability of a synchronous condenser, static VAr compensator, static compensator or other similar dynamic device; or
  8. it affects high voltage direct current facilities.
Note: Where a transmission outage requires generation curtailments, the adjustments to generation will typically happen in the hours before the scheduled transmission outage and in the hour after the element is returned to service.

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Owner From To Duration Element Scheduled Activity Affected Intertie
Syncrude 04-Oct-18 09:00 20-Mar-20 20:00 533.46 Days
Continuous		 Mildred T3 (Syncrude Mildred Lake) damaged transformer repairs (P2039)  
EPCOR 06-Jan-20 07:00 10-Feb-20 17:00 35.42 Days
Continuous		 Isolation of 1139L from E816S Petrolia S/S and 376S Harry Smith S/S cut in of 1139L and 1164L into Riverview S/S as part of Riverview energization  
ALTALINK, EPCOR 06-Jan-20 08:00 10-Feb-20 17:00 35.38 Days
Continuous		 1139L (367s Harry Smith - 816s Petrolia) cutting in EPCOR new sub (Riverview) to Altalink 1139L  
ATCO 20-Jan-20 08:00 02-Feb-20 17:00 13.38 Days
Continuous		 7L64 (930s Arcenciel - 7L64D5) Contractor replacing structures and crossarms  
ATCO 20-Jan-20 08:00 03-Feb-20 16:00 14.33 Days
Continuous		 740s 701 (740s H.R. Milner) maintenance  
BCH 20-Jan-20 08:30 07-Feb-20 17:30 18.38 Days
Continuous		 1L274 (48s Pocaterra - Britt Creek) refurbishment project AB-BC
ENMAX, ALTALINK 29-Jan-20 07:15 04-Feb-20 16:00 6.36 Days
Continuous		 918L (281s Johnson - 162s Beddington) component replacement and installing interphase spacers on 918L circuit between structures 791-828  
ALTALINK 29-Jan-20 07:15 04-Feb-20 16:45 6.4 Days
Continuous		 918L (281s -162s) GOI Performing component replacement and installing interphase spacers on 918L circuit between structures 791-828. Portion of circuit parallels 771L on same towers and requires a reclosure block when work is taking place.  
ALTALINK 03-Feb-20 07:00 06-Feb-20 17:00 3.42 Days
Continuous		 930L (37s - Poundmaker) Info Outage to 930L required for Epcor relay maintenance and op- checks.  
EPCOR 03-Feb-20 07:00 07-Feb-20 17:00 4.42 Days
Continuous		 Bellamy S/S TX2 Outage Outage to TX2 required for relay maintenance op-checks  
BCH 03-Feb-20 07:00 13-Feb-20 16:00 10.38 Days
Continuous		 1L274 (48s Pocaterra - Britt Creek) Refurbishment project AB-BC
ATCO 03-Feb-20 08:00 10-Feb-20 16:00 7.33 Days
Continuous		 9L43 (888s Dover - 874s McKay River) OOS for repairs  
ATCO 03-Feb-20 09:00 10-Feb-20 17:00 7.33 Days
Continuous		 7L63 7L63 crossarm replacements  
ALTALINK 03-Feb-20 10:00 04-Feb-20 17:00 31 Hours
Continuous		 71s1552 - GOI Settings Changes of Sync Check and Functional Testing on 71s1552 CUH90 relay.Single breaker outage in breaker-and-a-half scheme.  
ALTALINK 03-Feb-20 12:15 06-Feb-20 17:45 3.23 Days
Continuous		 794L (157s-A819s) - GOI 794L Components Str's Range 9-258  
ALTALINK 05-Feb-20 07:30 05-Feb-20 17:30 10 Hours
Daily		 310p152 (affects 974L) GOI Replace 1 CT. Will need a 15 minute outage to 974L for energization of the CT due to safe switching requirements  
ALTALINK 05-Feb-20 10:00 06-Feb-20 17:00 31 Hours
Continuous		 71s1452 - GOI Settings Changes of Sync Check and Functional Testing on 71s1452 CUH90 relay.Single breaker outage in breaker-and-a-half scheme.  
ALTALINK 05-Feb-20 23:00 06-Feb-20 04:00 5 Hours
Daily		 62s11 Advice for TransAlta Brushgear and blackstart test  
ALTALINK 06-Feb-20 04:00 06-Feb-20 07:00 3 Hours
Daily		 62s12 Advice for TransAlta Brushgear  
ALTALINK 06-Feb-20 08:00 06-Feb-20 17:00 9 Hours
Daily		 33s6 (33s Spray) maintenance  
ALTALINK 07-Feb-20 07:00 13-Feb-20 18:00 6.46 Days
Continuous		 948L (650s-A863s) - GOI 948L Component Replacements Str 4 - 186  
EPCOR 10-Feb-20 07:00 14-Feb-20 17:00 4.42 Days
Continuous		 Pounmaker/Jasper S/S 1098L outage Outage to 1098L required for relay maintenance and op-checks  
ENMAX 10-Feb-20 08:00 11-Feb-20 16:00 1.33 Days
Continuous		 932L HV SW maint SW144, SW145, MD-932L  
ENMAX, ALTALINK 10-Feb-20 08:00 11-Feb-20 16:00 1.33 Days
Daily		 932L (74s Janet - 162s Beddington) Line Protection Upgrade  
Syncrude 10-Feb-20 08:00 19-Feb-20 19:00 9.46 Days
Continuous		 AL-2 (D05 Syncrude - Aurora), Significant Outage - AL2 powerline (260 kV) will be taken offline to perform line repairs. In G01 Substation, following will be operated to isolate AL2 line: CB # 222 and 223 MOD # 222B, 223A and 223 In D05 Substation, following will be operated to isolate AL2 line: CB # 511 and 512 MOD # 511B Significant Outage - AL2 powerline (260 kV) will be taken offline to perform line repairs.

In G01 Substation, following will be operated to isolate AL2 line:

CB # 222 and 223
MOD # 222B, 223A and 223

In D05 Substation, following will be operated to isolate AL2 line:

CB # 511 and 512
MOD # 511B, 512A and 514		  
ATCO 10-Feb-20 08:00 23-Feb-20 17:00 13.38 Days
Continuous		 7L64 Contractor replacing structures and crossarms  
ATCO 10-Feb-20 11:00 21-Feb-20 14:00 11.13 Days
Continuous		 7L230 7L230 Xarms & Insulators  
ALTALINK 10-Feb-20 12:15 13-Feb-20 17:45 3.23 Days
Daily		 794L (157s-A819s) - GOI Component Replacements STR 9-258  
ALTALINK 11-Feb-20 08:30 13-Feb-20 18:00 2.4 Days
Continuous		 417L (55s - 281s) GOI Replace 417L Structure 62 for line clearance mitigation  
BCH 11-Feb-20 09:00 12-Feb-20 17:00 1.33 Days
Continuous		 Natal T2 (BCH Natal) Non-Elec PN PM AB-BC
ALTALINK 12-Feb-20 08:00 13-Feb-20 16:00 1.33 Days
Continuous		 103s T1 and 138kV Bus 1 GOI, 103s T1 (103s Goose Lake) Replace A phase PT of VT7/SS2  
ALTALINK 12-Feb-20 09:00 12-Feb-20 16:00 7 Hours
Daily		 1116L (170s-167s)- GOI Marker Ball Installation Str's 69-70  
EPCOR 13-Feb-20 07:00 14-Feb-20 17:00 1.42 Days
Continuous		 Dome S/S TX2 Outage Outage to TX2 required for relay maintenance op-checks  
ATCO 13-Feb-20 09:00 13-Feb-20 13:00 4 Hours
Continuous		 715S 702, 7L91 PRC 005 Trip Coil Testing, 7L91 will require to be open ended for duration of work  
EPCOR 17-Feb-20 07:00 21-Feb-20 17:00 4.42 Days
Continuous		 Poundmaker S/S Tx2 outage Outage to Tx2 required for relay maintenance and op-checks  
ATCO 17-Feb-20 08:00 21-Feb-20 16:00 4.33 Days
Continuous		 951S SVC To correct deficiencies that were identified during the initial energization period of Thickwood SVC,  
ENMAX 17-Feb-20 08:00 22-Mar-20 16:00 34.29 Days
Continuous		 162.81L (ENMAX 162 Beddington - 391S Balzac) Line Protection Upgrade. (Original outage date Feb 3rd)  
BCH 18-Feb-20 09:00 21-Feb-20 17:00 3.33 Days
Continuous		 2L294 (Cranbrook - A.A. Lambert) Replace end of life structures AB-BC
ATCO 18-Feb-20 09:00 26-Feb-20 17:00 8.33 Days
Continuous		 7L63 7L63 crossarm replacements  
ALTALINK 18-Feb-20 09:00 08-Mar-20 18:30 19.35 Days
Continuous		 310P T30 (Tx 18153) - GOI Corrosive Sulphur Mitigation  
ATCO 18-Feb-20 09:00 27-Mar-20 16:00 38.25 Days
Continuous		 9L100 (801s Anderson - 807s Sheerness), 807s 902T (807s Sheerness), 807S 902 807S BKR 902 maintenance & 9L100 protection upgrade  
ATCO 18-Feb-20 11:00 18-Feb-20 16:00 5 Hours
Continuous		 715S 703, 7L66 PRC 005 Trip Coil Testing, 7L66 will be open ended for duration of work  
ALTALINK 18-Feb-20 11:30 18-Feb-20 17:00 5.5 Hours
Daily		 632s PS1 (Tx 18793) GOI Replace cabinet heater in 632s452  
ALTALINK 18-Feb-20 12:15 20-Feb-20 17:45 2.23 Days
Continuous		 794L (157s-A819s) - GOI Component Replacements STR 9-258  
ALTALINK 19-Feb-20 07:00 23-Feb-20 17:00 4.42 Days
Continuous		 786L (799s Coleman - Natal) Emergency Repair: Install clampstar assemblies over hot sleeves and replace hot conductor on multiple spans between Str 73 - 121 AB-BC
ATCO 19-Feb-20 08:30 19-Feb-20 17:00 8.5 Hours
Continuous		 7L28 Clearance Mitigation  
ATCO 19-Feb-20 08:30 19-Feb-20 17:00 8.5 Hours
Continuous		 9L27 Clearance Mitigation  
ATCO 20-Feb-20 09:00 20-Feb-20 13:00 4 Hours
Continuous		 715S 701, 7L583 PRC 005 Trip Coil Testing, 7L583 will be open ended for duration of work  
ATCO 20-Feb-20 09:00 20-Feb-20 17:00 8 Hours
Continuous		 7L224 Clearance Mitigation on one structure  
EPCOR 24-Feb-20 07:00 28-Feb-20 17:00 4.42 Days
Continuous		 Poundmaker S/S Tx3 outage Outage to Tx3 required for relay maintenance and op-checks  
ALTALINK 24-Feb-20 07:00 28-Feb-20 17:00 4.42 Days
Continuous		 170L (632s Russell - 799s Coleman) Emergency Repair: Install clampstar assemblies over hot Sleeves and sleeve out hot conductor in multiple spans between Str 1K - 31 AB-BC
ENMAX 24-Feb-20 08:00 25-Feb-20 16:00 1.33 Days
Continuous		 2.1CAP Substation Building Upgrades. Install Roxtec plugs in ducts  
ATCO 24-Feb-20 08:00 01-Mar-20 17:00 6.38 Days
Continuous		 7L59 (789s Keg River - 7L59 tap) FAC-008 line to ground mitigation  
ALTALINK 25-Feb-20 08:00 27-Feb-20 17:45 2.41 Days
Continuous		 794L (157s-A819s) - GOI 794L Components Replacements Str's 9-258  
ATCO 25-Feb-20 08:00 28-Feb-20 16:00 3.33 Days
Continuous		 7L45 (798s Bridge Creek - 813s Little Smoky) Raise power poles for mitigation, use phase raise system to raise line, Associated with 7L46 HOP # 2-51016  
ATCO 25-Feb-20 08:00 28-Feb-20 16:00 3.33 Days
Continuous		 7L46 (845s Big Mountain - 813s Little Smoky) Raise power poles for mitigation, use phase raise system to raise line, Associated with 7L45 GOI # 2-51015  
ENMAX 26-Feb-20 08:00 27-Feb-20 16:00 1.33 Days
Continuous		 832L. 12PT138-Z31. 12.1TR HV SW maint SW84, SW85, SW86, MD-12.1TR. Check reversing sw.  
EPCOR 27-Feb-20 09:00 27-Feb-20 15:00 6 Hours
Continuous		 J2403 Switch and breaker operation for NAIT Student Demo  
ENMAX 28-Feb-20 08:00 29-Feb-20 16:00 1.33 Days
Continuous		 833L. 12PT138-Z31. 12.2TR HV SW maint SW81, SW82, SW83, MD-12.2TR. Check reversing sw. Contractor applying Roxtec duct seal at 2sub  
ATCO 29-Feb-20 09:00 04-Mar-20 15:00 4.25 Days
Continuous		 7L32 (862s South Bezanson - 813s Little Smoky) Line Mitigation  
EPCOR 02-Mar-20 07:00 06-Mar-20 17:00 4.42 Days
Continuous		 Poundmaker S/S 930L Outage Outage to 930L required for relay maintenance and op-checks  
EPCOR 02-Mar-20 08:00 02-Mar-20 17:00 9 Hours
Continuous		 Cloverbar S/S 921L bay outage Relay maintenance and op-checks to 921L protection  
ENMAX 02-Mar-20 08:00 03-Mar-20 16:00 1.33 Days
Continuous		 162.81L (ENMAX 162 Beddington - 391S Balzac) HV SW maint SW82, SW83, MD-162.81  
ATCO 02-Mar-20 08:00 15-Mar-20 17:00 13.33 Days
Continuous		 7L64 Contractor replacing structures and crossarms  
ATCO 02-Mar-20 09:00 11-Mar-20 17:00 9.29 Days
Continuous		 7L63 7L63 crossarm replacements  
ALTALINK 02-Mar-20 12:15 05-Mar-20 17:45 3.23 Days
Continuous		 794L (157s-A819s) - GOI 794L Components Replacements Str's 9-258  
EPCOR 04-Mar-20 08:00 04-Mar-20 17:00 9 Hours
Continuous		 987s T2 (987s Clover Bar) Relay maintenance and op-checks to Tx2 protection . Outage will affect Tx4 on Cloverbar POD S/S.  
ALTALINK 04-Mar-20 08:30 04-Mar-20 17:00 8.5 Hours
Daily		 336s 612 (336s Fincastle), 612L (336s Fincastle - 368s Burdett) 138kV breaker maintenance  
ALTALINK 06-Mar-20 07:00 15-Mar-20 17:30 9.4 Days
Continuous		 948L (650s Hansman Lake - 863s Paintearth) 948L Component Replacements  
EPCOR 09-Mar-20 07:00 10-Mar-20 17:00 1.42 Days
Continuous		 Jasper S/S J240C1 Cap bank outage, 805s C1 (805s Jasper) Relay maintenance op-checks  
EPCOR 09-Mar-20 07:00 13-Mar-20 17:00 4.42 Days
Continuous		 330P 12TC1 (330p Genesee) Relay repair/maintenance op-checks  
ALTALINK 09-Mar-20 09:00 12-Mar-20 16:00 3.29 Days
Continuous		 2s T1 (Tx18633) / 87L GOI 138kV VT Replacement  
EPCOR 09-Mar-20 09:30 11-Mar-20 17:00 2.31 Days
Continuous		 TX#1 and 909LE Outage to TX#1 required for relay mtce op-checks and installation of new 240 KV breaker  
EPCOR 11-Mar-20 07:00 11-Mar-20 11:00 4 Hours
Continuous		 805s J2403 (805s Jasper) Relay maintenance op-checks  
EPCOR 11-Mar-20 12:00 11-Mar-20 17:00 5 Hours
Continuous		 805s J2404 (805s Jasper) Relay maintenance op-checks  
EPCOR 12-Mar-20 07:00 12-Mar-20 11:00 4 Hours
Continuous		 805s J2405 (805s Jasper) Relay maintenance op-checks  
EPCOR 12-Mar-20 12:00 12-Mar-20 17:00 5 Hours
Continuous		 805s J2406 (805s Jasper) Relay maintenance op-checks  
EPCOR 16-Mar-20 07:00 20-Mar-20 17:00 4.42 Days
Continuous		 330P 12TC2 (330p Genesee) Relay maintenance op-checks  
ALTALINK 16-Mar-20 08:00 20-Mar-20 13:00 4.21 Days
Continuous		 901L(63s-64s-74s) - Advice Line protection upgrade for 901L at all three stations (three terminal line). Includes relay replacements/setting changes at 63s/74s and relay firmware/setting changes at 64s. Line breakers will be required for outage duration for commissioning purposes. Line outage and protection upgrade only.  
ATCO 16-Mar-20 08:00 20-Mar-20 16:00 4.33 Days
Continuous		 7L28 (717s Ethel Lake - 846s Grand Centre) 701 BKR and Ct maintenance 7L28 will be open at 846S

Relay protection upgrade panel 7l28 (panel 1c)
86-50BF/700BS1 partial install/testing (panel 1c)
Install new relay (21A-Siemens)
Change CT cores going to relays (701CT work)
Demo metering from ION 7300, metering will be done through SEL relay after.
Commission wiring/relays/CT-ratios		  
ALTALINK 17-Mar-20 08:00 17-Mar-20 17:30 9.5 Hours
Daily		 63sT1 (Tx 18310) & 63s24 GOI CB 1480 (63S24) SF6 138KV DT1 Breaker Maintenance  
ALTALINK 18-Mar-20 07:30 18-Mar-20 17:30 10 Hours
Daily		 370s T5 (370s North Lethbridge) replace diverter lid/gear box and replace oil in diverters  
ALTALINK 18-Mar-20 08:00 18-Mar-20 17:30 9.5 Hours
Daily		 63sT2 (Tx 18898) & 63s25 GOI CB 1478 (63S25) SF6 138KV DT1 Breaker Maintenance  
ATCO 18-Mar-20 09:00 21-Mar-20 16:00 3.29 Days
Continuous		 7L50 crew do some conductor sampling on 7L50 , which means that I have to splice out some fairly large pieces of conductor.  
ENMAX 19-Mar-20 08:00 19-Mar-20 12:00 4 Hours
Continuous		 28.80L. 28.2TR. 28PT138-Z31 Spring Substation Washing  
ALTALINK 21-Mar-20 07:00 30-Mar-20 18:00 9.46 Days
Continuous		 948L (650s-A863s) - GOI 948L Component Replacements  
Syncrude 21-Mar-20 09:00 01-Apr-20 20:00 11.46 Days
Continuous		 De-energize temporary transformer (G15) to install new transformer T3 (72kV / 13.8kV) at Plant 31 Substation. CB # 3235, 335 and MOB # 334 will be operated for this scope of work. De-energize temporary transformer (G15) to install new transformer T3 (72kV / 13.8kV) at Plant 31 Substation. CB # 3235, 335 and MOB # 334 will be operated for this scope of work.  
EPCOR 23-Mar-20 07:00 23-Mar-20 17:00 10 Hours
Continuous		 330p 1202 (330p Genesee) Relay maintenance op-checks  
ALTALINK 23-Mar-20 08:00 24-Mar-20 18:00 1.42 Days
Continuous		 936L (5s - 102s) GOI Line Clearance Mitigation Insulators 936L50 Double circuit 937L  
ATCO 23-Mar-20 08:00 05-Apr-20 17:00 13.38 Days
Continuous		 7L64 Contractor replacing structures and crossarms
Note: this work is dependant on frozen ground to proceed.		  
EPCOR 24-Mar-20 07:00 24-Mar-20 17:00 10 Hours
Continuous		 330p 1205 (330p Genesee) Relay maintenance op-checks  
ALTALINK, ENMAX 24-Mar-20 08:15 24-Mar-20 17:15 9 Hours
Daily		 44s36.81E (36.81L) GOI, 36.81L (44s Bearspaw - ENMAX 36) 138kV breaker maintenance  
EPCOR 25-Mar-20 07:00 25-Mar-20 17:00 10 Hours
Continuous		 330p 1208 (330p Genesee) Relay maintenance op-checks  
ALTALINK 25-Mar-20 07:00 26-Mar-20 18:00 1.46 Days
Continuous		 937L (5s - 102s) GOI Line Clearance Mitigation Insulators 936L50 Double circuit 936L  
ALTALINK 25-Mar-20 08:15 25-Mar-20 17:15 9 Hours
Daily		 44s50X (50L) GOI, 50L (44s Bearspaw Plant - ENMAX 21) 138kV breaker maintenance  
ENMAX 26-Mar-20 08:00 26-Mar-20 12:00 4 Hours
Continuous		 693L. 10.2TR. 10PT138-Z31 Substation Washing  
ENMAX 26-Mar-20 12:00 26-Mar-20 18:00 6 Hours
Continuous		 832L. 10.1TR. 10PT138-Z31 Substation Washing  
ATCO 30-Mar-20 08:00 13-Apr-20 16:00 14.33 Days
Continuous		 740S 705, 7L80 (740s H.R.Milner - 733s Simonette) replace 705 PT and 705 CT
7L80 required open ended for the duration		  
ATCO 30-Mar-20 09:00 02-Apr-20 14:00 3.21 Days
Continuous		 7L22 Customer road move for county of grande prairie  
ATCO 30-Mar-20 10:00 02-Apr-20 15:00 3.21 Days
Continuous		 7L22 For MD Road move  
ENMAX 30-Mar-20 12:00 30-Mar-20 18:00 6 Hours
Continuous		 23.80L. 23.4TR Spring Substation Washing  
ALTALINK 30-Mar-20 12:30 02-Apr-20 17:00 3.19 Days
Continuous		 650s752 - GOI Techs to fix nitrogen gas leak on 650s752  
ALTALINK 01-Apr-20 07:00 01-Apr-20 18:00 11 Hours
Daily		 747L (37s-E113s-747L3A)- GOI, 747L (37s North Calder - 99s North St Albert) Line Clearance Mitigation Str's 1C and 2  
ALTALINK, EPCOR 17-Apr-20 07:00 19-Apr-20 17:00 2.42 Days
Continuous		 747L (37s North Calder - 99s North St Albert), 711L (Inland Cement - 747L tap) 711L4 Air Break - Replacement  
ENMAX 20-Apr-20 08:00 22-Apr-20 12:00 2.17 Days
Continuous		 65.1TR (ENMAX 65) T-60 Upgrade Phase 2. Oil sampling MT, TC, Check reversing switch  
SUNCOR 20-Apr-20 08:00 26-Apr-20 18:00 6.42 Days
Continuous		 29PL6-3 & A/B Line protection(from 30EDD-1/29EDD-1) 72kV Line 29PL6-3 outage for Line A/B Protection Upgrades  
ALTALINK 20-Apr-20 12:00 23-Apr-20 17:00 3.21 Days
Continuous		 268s T1 and VR1 - GOI High and low side bushings replacement on T1  
ENMAX 22-Apr-20 12:00 24-Apr-20 16:00 2.17 Days
Continuous		 65.2TR (ENMAX 65) T-60 Upgrade Phase 2. Oil sampling MT, TC. Check reversing switch  
ALTALINK, EPCOR 25-Apr-20 07:00 26-Apr-20 17:00 1.42 Days
Continuous		 711L (Inland Cement - 747L tap), 747L (37s North Calder - 99s North St Albert) 711L4 Air Break Replacement  
ALTALINK 28-Apr-20 07:00 29-Apr-20 17:30 1.44 Days
Continuous		 33s 138kV Bus (76L, 84L, 113L) GOI 33sSS1/33s5 arcing (when opening 33s5 witnessed an arc from the opening blade of 33s5 to the head of SS1), SS1 (120V secondary cables of the SS PT have arced to clamps; Re-insulate cables), 33s8 middle phase does not close, 138kV breaker maintenance (33s1). Changing insulators and reconductering  
ALTALINK 06-May-20 08:30 07-May-20 17:30 1.38 Days
Continuous		 250p T2 (Tx 18227) GOI CB 779 (250P2) MO 138KV HPF Breaker Maintenance. Generator 2 will be offline during this outage. Coincides with TAU scheduled maintenance outage.  
ENMAX 07-May-20 08:00 22-May-20 18:00 15.42 Days
Continuous		 36.81L. Haskayne line raise project. Raising the line and replacing 4 structures to accommodate a new road construction.  
ALTALINK, ENMAX 07-May-20 08:00 22-May-20 18:00 15.42 Days
Continuous		 36.81L Enmax - Advice, 36.81L (44s Bearspaw - ENMAX 36) Haskayne line raise project. Raising the line and replacing 4 structures to accommodate a new road construction.  
SUNCOR 09-May-20 08:00 15-May-20 18:00 6.42 Days
Continuous		 29PL9-56 Line outage to perform 5/10yr PM 29PL9-14 buss 29PP-41C and transformer 29PT-191 :
29EDD56;29PT-191 SYSTEM;PM 5Y/10Y,
Repair OHSW bonds to towers PL9-14/15,
29PL9-14, Reconnect Suspension Clamp,
29PL9-14, Repair OH Shield Bonds,
29EDD56;652-4170 MAINT & TEST;PM 10y,
29EDD-56 29PT-191 Oil Leak Repairs		  
ATCO 11-May-20 08:00 22-May-20 16:00 11.33 Days
Continuous		 7L91 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ATCO 12-May-20 08:00 14-May-20 16:00 2.33 Days
Continuous		 801S 901T 801S Anderson 901T Oil Reclaiming
Will also be changing 14.4 KV PT and doing BKR 704 maintenance at the same time		  
ATCO 12-May-20 08:00 19-May-20 16:00 7.33 Days
Continuous		 743S 502VR, 743S 702T Adding Razor Energy DG at Sarah Lake  
ATCO 25-May-20 08:00 05-Jun-20 16:00 11.33 Days
Continuous		 7L89 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ENMAX 01-Jun-20 08:00 05-Jun-20 16:00 4.33 Days
Continuous		 162.1TR HV SW maint SW131, SW141, SW81, SW96, MD138-162.1TR, MD240-162.1TR. Oil sampling 162.1 MT, TC, Bushing. Replace sw mech SW131, SW141. Check reversing sw.  
ENMAX 01-Jun-20 08:00 14-Jun-20 16:00 13.33 Days
Continuous		 162.1TR B protection upgrade. Commission new circuits  
ALTALINK 01-Jun-20 09:00 02-Jul-20 18:00 31.38 Days
Continuous		 50L (44s - 21s) GOI Structures Range 131-143. Modifications on 131-132. New Self Supporting Steel Dead end structures at 133-134. New Dead End H-Frame structures at 141-143. Structure 142 to be salvaged.  
ALTALINK 02-Jun-20 07:00 02-Jun-20 19:00 12 Hours
Continuous		 745AL (745L480-411s745A-975s1-745L482 -, 745AL (745AL - 745L tap), 745L (39s Bickerdike - 602s Cold Creek) Urgent Fire Mitigation. Scope of work includes maintenance on Structures 745A1L957s Dalehurst East Bay And 745ALJCT-745AL3 & 745A1L1 and Str 9 on 740AL Scheduled: Shannon Bouchard Issue To: Ken Teasdale Contact #: 403.360.4960  
EPCOR 08-Jun-20 07:00 12-Jun-20 17:00 4.42 Days
Continuous		 TX1 @ Castledowns MV protection cutover  
ATCO 08-Jun-20 08:00 19-Jun-20 16:00 11.33 Days
Continuous		 7L587 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ALTALINK 11-Jun-20 08:00 14-Jun-20 17:00 3.38 Days
Continuous		 202L (62s-61s)- GOI Fire Mitigation / Maintenance on Strs 137, 138, 139, 141, 156 and 163  
ATCO 22-Jun-20 08:00 10-Aug-20 16:00 49.33 Days
Continuous		 826S 901T 240/144kV Breaker Fail Protection
(901T OOS for duration of outages)

826S Marguerite P&C Upgrade		  
EPCOR 06-Jul-20 07:00 17-Jul-20 17:00 11.42 Days
Continuous		 TX3 @ Jasper DGA monitor  
SUNCOR 11-Jul-20 08:00 09-Aug-20 18:00 29.42 Days
Continuous		 29EDD-3 Line outage to perform 5/10yr PM 29PL9-3 29PT-6 AT GTG6:
29EDD-3;29PL9-3/GTG-6 15KVEQ SYSTEM;PM 5y,
29EDD-3 29PT-6 LEAKS - PRESSURE WASH		  
ATCO 03-Aug-20 07:00 03-Nov-20 17:00 92.46 Days
Continuous		 972S 905B Halkirk 2 Windfarm Project  
ATCO 17-Aug-20 08:00 05-Oct-20 16:00 49.33 Days
Continuous		 826S 902T 240/144kV Breaker Fail Protection
(902T OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ALTALINK 24-Aug-20 08:00 03-Sep-20 18:00 10.42 Days
Continuous		 1325L (510s - 511s) - GOI Annual inspection & maintenance  
EPCOR 31-Aug-20 07:00 25-Sep-20 17:00 25.42 Days
Continuous		 TX4 @ Jasper Bushing Replacement & Oil Work  
ATCO 01-Sep-20 08:00 14-Sep-20 16:00 13.33 Days
Continuous		 731s 701T (731s Elmworth), 7L03 (7L03D3 - 731s Elmworth) 731S Elmworth Bkr Replacement and Protection Upgrade

Outgae on 701T/7L03 (Isolation points - 501VRA, 501VRB,
501VRX, 700D1, 7L03D4, TBD for mobile sub on 25 kV bus)		  
ATCO 14-Sep-20 07:00 23-Sep-20 17:00 9.42 Days
Continuous		 972S 900BS1 Installing new 240Kv Bay (connect 907B to BUS 1) for 620S Goldeye substation connection  
ATCO 14-Sep-20 08:00 28-Sep-20 16:00 14.33 Days
Continuous		 7L69 (815s Goodfare - 731s Elmworth) 731S Elmworth Bkr Replacement and Protection Upgrade

Outage on 7L69		  
SUNCOR 14-Sep-20 09:00 20-Sep-20 18:00 6.38 Days
Continuous		 29EDD-1 5yr and 10 yr maintenance on 29CTT-1 in 29EDD-1

Elements not available:
29CVT-1, 29PL9-2		  
EPCOR 21-Sep-20 07:00 25-Sep-20 17:00 4.42 Days
Continuous		 1044L east @ Jasper - Petrolia Vt Replacement  
ATCO 23-Sep-20 07:00 25-Sep-20 17:00 2.42 Days
Continuous		 972S 900BS2, 9L16 Installing new 240Kv Bay (connect 909A to BUS 2) for 620S Goldeye substation connection
Cutover 9L16 to New Bay		  
ATCO 25-Sep-20 07:00 28-Sep-20 17:00 3.42 Days
Continuous		 9L177 Installing new 240Kv Bay for 620S Goldeye substation connection
Cutover 9L177 to New Bay		  
ATCO 28-Sep-20 07:00 29-Sep-20 17:00 1.42 Days
Continuous		 9L62 Installing new 240Kv Bay for 620S Goldeye substation connection
String 9L62 into 972S Tinchebray		  
SUNCOR 28-Sep-20 08:00 05-Oct-20 18:00 7.42 Days
Continuous		 29EDD-56 PL9-15 OUTAGE 5YR SYSTEM PM, 29PT-190 AND BREAKER 652-4110:
29EDD-56;29PT-190 SYSTEM;PM 5y,
29EDD-56;652-4110 MAINT & TEST;PM 10y,
Repair OHSW bonds to towers PL9-14/15
29EDD-56 Repair Leak 29PT-190		  
ENMAX 09-Oct-20 08:00 12-Oct-20 16:00 3.33 Days
Continuous		 162s PT-Z41. 1-GSU-XF-0001 Replace 87-XF1 B differential protection. Commission checks and trip testing  
ENMAX 09-Oct-20 08:00 12-Oct-20 16:00 3.33 Days
Continuous		 162s. 1-GSU HV SW maint SW133, SW132. Replace switch mech. SW132, SW133  
ATCO 12-Oct-20 08:00 23-Oct-20 16:00 11.33 Days
Continuous		 9L36 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
EPCOR 13-Oct-20 07:00 23-Oct-20 17:00 10.42 Days
Continuous		 TX1 @ Petrolia DGA Install  
ATCO 22-Oct-20 07:00 27-Oct-20 17:00 5.42 Days
Continuous		 7L65, 7L77 7L65 Rebuild Project  
ATCO 26-Oct-20 08:00 07-Nov-20 16:00 12.38 Days
Continuous		 9L37 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
EPCOR 16-Nov-20 07:00 27-Nov-20 17:00 11.42 Days
Continuous		 CV5 @ Castledowns & Victoria maint and splice repair  
EPCOR 23-Nov-20 07:00 27-Nov-20 17:00 4.42 Days
Continuous		 TX2 @ Castledowns TX protection cutover  
ATCO 05-Dec-20 07:00 11-Dec-20 16:00 6.38 Days
Continuous		 9L59 Outage for Garden Plain Wind Project  
ATCO 05-Jan-21 08:00 08-Jan-21 16:00 3.33 Days
Continuous		 9L20 56772 Nevis Transformer Addition
9L20 Open -ended		  
ATCO 09-Jan-21 08:00 12-Jan-21 16:00 3.33 Days
Continuous		 9L912 56772 Nevis Transformer Addition
9L912 Open -ended		  
ATCO 20-Jan-21 08:00 23-Feb-21 16:00 34.33 Days
Continuous		 951S 900BS2, 951S 908, 951S 906, 951S 903 951S construction for 9L162 & 9L193 addition
AESO should be notified of any changes to below workplan:

Jan 20, 2021 – Feb 20, 2021
Isolation pts: 908B,909A
Impact: BKR 908 OOS
Scope of work: Demo bus & install 909A & 909B
Feb 21, 2021 – Feb 23, 2021
Expand to isolation pts:903B, 906B,908B
Impact: BKR 903,BKR 906, 900BS2 OOS
Scope of work: Make connections to 909A & 912A		  
ATCO 25-Jan-21 08:00 26-Jan-21 16:00 1.33 Days
Continuous		 766S 901T, 9L20, 9L912 56772 Nevis Transformer Addition
Tie-in to the new bus for 902T
901T OOS
9L20 OPEN-ENDED
9L912 OPEN-ENDED		  
ATCO 03-Feb-21 07:00 07-Feb-21 17:00 4.42 Days
Continuous		 9L101 Line move for mine expansion.
Attach new line to existing 9L101		  
ATCO 15-Feb-21 07:00 02-Mar-21 17:00 15.42 Days
Continuous		 972S 900BS2, 9L16 Outage on 907B and 908A for the installation and commissioning of 907 and 907CT  
ATCO 24-Feb-21 08:00 26-Feb-21 16:00 2.33 Days
Continuous		 951S 900BS1 951S construction for 240kv expansion - 9L162 & 9L193 addition
Connect 910A to 900BS1
Impact: 900BS1 OOS, BKR 901 OOS, BKR 904 OOS, BKR 907 OOS, 920C OOS		  
ATCO 01-Mar-21 07:00 02-Mar-21 17:00 1.42 Days
Continuous		 972S 900BS2, 9L16 Outage on 9L16 to cut the line over to the new bay  
ATCO 08-Mar-21 07:00 12-Mar-21 17:00 4.42 Days
Continuous		 9L177 Installing new 240Kv Bay (connect 907B to BUS 1) for 620S Goldeye substation connection  
ATCO 04-May-21 08:00 17-May-21 17:00 13.38 Days
Continuous		 9L02 Louise Creek Rebuild project
Wiring for 903/910BF relays.
CT ratio changes.
Relay programming and functionality.
Commission control, alarms and status.
Blocking procedures for BF protections.		  
ATCO 24-May-21 08:00 06-Jun-21 17:00 13.38 Days
Continuous		 9L40 Louise Creek Rebuild project
Wiring for 903/904BF relays.
CT ratio changes.
Relay programming and functionality.
Commission control, alarms and status.
Blocking procedures for BF protections.		  
ATCO 14-Jun-21 08:00 27-Jun-21 17:00 13.38 Days
Continuous		 9L05 Louise Creek Rebuild project
Wiring for 904/905BF relays.
CT ratio changes.
Relay programming and functionality.
Commission control, alarms and status.
Blocking procedures for BF and Bus protections.		  
ATCO 05-Jul-21 08:00 18-Jul-21 17:00 13.38 Days
Continuous		 9L939 Louise Creek Rebuild project
Wiring for 905/906BF relays.
CT ratio changes.
Relay programming.
Commission control, alarms and status.
Blocking procedures for BF and Bus protections.		  
ATCO 26-Jul-21 08:00 28-Sep-21 17:00 64.38 Days
Continuous		 809S 902T, 9L938 Louise Creek Rebuild project
Replace breakers' 911, 912, and 707.
Add new bus PT 700PT2.
Complete wiring for BF, 21A, 21B, and 701C relays.
CT ratio changes.
Commission apparatus.
Relay programming.
Commission control, alarms and status.
Blocking procedures for BF and Bus protections.		  
ATCO 29-Jul-21 08:00 05-Aug-21 17:00 7.38 Days
Continuous		 7L91 P&C wiring and commissioning associated to 7L208 work  
ATCO 04-Oct-21 08:00 17-Oct-21 17:00 13.38 Days
Continuous		 809S 901T Louise Creek Rebuild project
Switch station service to alternate.
Replace bus PT 900PT1.
Complete wiring for BF, 87TA, 87TB, and 51NGR relays.
CT ratio changes.
Commission apparatus.
Relay programming.
Commission control, alarms and status.
Blocking procedures for BF and Bus protections.		  

AB-BC, AB-SK & AB-MATL: refer to AESO web posting: http://itc.aeso.ca/itc/public/reportIndex.do
Also,
AB-BC, AB-SK & AB-MATL: refer to ISO Rule 203.6: http://www.aeso.ca/rulesprocedures/18592.html

Prepared On: 2020-01-22   3:33:23 PM


This document and the information contained herein are based upon information and data which by their nature contain a degree of uncertainty and are subject to change. In addition, this document may contain information and data from public sources and/or third parties, which have been assumed to be accurate and complete and have not been verified. Accordingly, the Independent System Operator, operating as the Alberta Electric System Operator (the "AESO") makes no warranty, representation or guarantee, express or implied, with respect to this document or the information contained herein, including, but not limited to, any warranty, representation or guarantee of accuracy, completeness, timeliness, reliability, availability, absence of computer virus, non- infringement, merchantability or suitability for any purpose. Under no circumstances will the AESO, its members, officers, employees, contractors or agents, or any of their respective affiliates, be liable for any errors or omissions in, or any losses, damages or claims whatsoever, whether in contract, tort or otherwise, arising from use of or reliance upon, this document or any information contained herein.

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