Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2019-11-23

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)  
ATCO 27-Oct-19 12:00 20-Dec-19 16:00 54.21 Days
Continuous		 740s H.R.Milner 144 kV Main Bus, 740s 703T (740s H.R.Milner) rebuild  
ALTALINK 04-Nov-19 12:00 25-Nov-19 18:00 21.25 Days
Continuous		 87s T2 (87s Gaetz) sulphur mitigation  
ALTALINK 12-Nov-19 11:00 11-Dec-19 14:00 29.13 Days
Continuous		 67s Stirling 69 kV Bus 1, 225L (67s Stirling - 225s Magrath), 67s T1 (67s Stirling) create open points C and D, connect mobile and replace 69 kV equipment  
ATCO, Syncrude 15-Nov-19 08:00 24-Nov-19 20:00 9.5 Days
Continuous		 848s 910 (848s Ruth Lake), 848s 911 (848s Ruth Lake), D05 513 (D05 Syncrude), D05 516 (D05 Syncrude), D05 517 (D05 Syncrude), D05 78 (D05 D05), RL1 (848s Ruth Lake - D05 Syncrude), D05 T2 (D05 Syncrude) substation outage  
Syncrude 16-Nov-19 08:00 25-Nov-19 20:00 9.5 Days
Continuous		 UE-1 30-2PTR72-A1 (UE-1) maintenance  
ATCO 18-Nov-19 08:00 25-Nov-19 16:00 7.33 Days
Continuous		 7L80 (740s H.R.Milner - 857s Kakwaridge) rebuild  
Syncrude, ATCO 18-Nov-19 08:00 27-Nov-19 20:00 9.5 Days
Continuous		 RL1 (848s Ruth Lake - D05 Syncrude), D05 T2 (D05 Syncrude), 848s 910 (848s Ruth Lake), 848s 911 (848s Ruth Lake), D05 517 (D05 Syncrude), D05 516 (D05 Syncrude), D05 513 (D05 Syncrude), D05 78 (D05 D05) substation outage  
ENMAX, ALTALINK 18-Nov-19 08:00 19-Dec-19 16:00 31.33 Days
Continuous		 918L (281s Johnson - 162s Beddington), 281s 252(281s Johnson), 281s 552(281s Johnson), 162s 240-RB132 (162s Beddington), 162s 240-RB133 (162s Beddington) line protection upgrade  
ENMAX 24-Nov-19 08:00 24-Nov-19 12:00 4 Hours
Continuous		 24.81L. 24.83. 24.1TR. 24PT138-Z31, 24.81L (ENMAX 31 - ENMAX 24) RTU upgrade. CAC OAC commissioning. Control Center will have no control on equipment  
ENMAX 25-Nov-19 08:00 26-Nov-19 18:00 1.42 Days
Continuous		 162.2TR (ENMAX 162 Beddington) Oil sampling bushing, TC. Check reversing switch. Replace switch mech. SW136  
BCH 25-Nov-19 08:00 27-Nov-19 19:00 2.46 Days
Continuous		 5L52 (Ingledow - Custer) BPA work AB-BC
ALTALINK 25-Nov-19 09:00 29-Nov-19 16:00 4.29 Days
Continuous		 59s T1(18184) & 138kV Bus(616L) - GOI, 616L (59s Peigan - 103s Goose Lake) Replace 138kv switches like for like, (59s5, 6 and 10) and post insulators.  
ALTALINK 25-Nov-19 10:00 28-Nov-19 15:00 3.21 Days
Continuous		 912L (63s-766s) - Advice, 912L (63s Red Deer - 766s Nevis) Migrate and commission all L4 – 912L at 63S Red Deer associated line protections, breakers, breaker fail and Tele-protection alarms, status, controls, metering and remote access to new RTU and LAN. Migrate and commission VT-4 alarms. Replace and commission new 63s912E (889) airbreak control module.  
ALTALINK, ENMAX 25-Nov-19 11:00 28-Nov-19 17:00 3.25 Days
Continuous		 1003L (74s - ENMAX 25SUB) Advice, 1003L (74s Janet - ENMAX 25) SCADA equipment upgrade, migrate new alarms, controls, analogs and remote access to new SCADA system.  
ATCO 25-Nov-19 12:00 29-Nov-19 12:00 4 Days
Continuous		 7L73, 7L73 (829s Boucher Creek - 800s Friedenstal) Line Maintenance  
ENMAX 27-Nov-19 08:00 28-Nov-19 18:00 1.42 Days
Continuous		 162.1TR, 162.1TR (ENMAX 162s Beddington) Oil sampling bushing, TC. Check reversing switch. Replace switch mech. SW131, SW141  
Syncrude 27-Nov-19 08:00 02-Dec-19 20:00 5.5 Days
Continuous		 Significant outage - D05 Substation 260/72 kV Outage - Zone 3. Following Cicuit Breakers will operated: 902 (Ruth Lake – by ATCO only after RL-1 power has been restored) 907 (Ruth Lake – by ATCO only after RL-1 power has been restored). CB 512, 513 at D05. Following MOD will be Operated: RL-2D1 (Ruth Lake – by ATCO only after RL-1 power has been restored) 515, 512A, 512B, 513A, 513B at D05. Significant outage - D05 Substation 260/72 kV Outage - Zone 3.
Following Cicuit Breakers will operated: 902 (Ruth Lake – by ATCO only after RL-1 power has been restored)
907 (Ruth Lake – by ATCO only after RL-1 power has been restored). CB 512, 513 at D05.

Following MOD will be Operated:
RL-2D1 (Ruth Lake – by ATCO only after RL-1 power has been restored) 515, 512A, 512B, 513A, 513B at D05.		  
BCH 28-Nov-19 08:20 29-Nov-19 04:00 19.67 Hours
Continuous		 1L274 (1D2L274 - 1D3L274) annual maintenance AB-BC
ALTALINK 28-Nov-19 12:05 02-Dec-19 12:30 4.02 Days
Continuous		 58s153W GOI Trip wiring and commissioning to breaker 53s153W from 38B/B87 protection relay, replace strain insulators on 153L structure.  
ALTALINK 30-Nov-19 07:30 30-Nov-19 17:30 10 Hours
Daily		 702L (137s-A757s) ATCO - Advice, 702L (137s Sedgewick - 757s Battle River) ATCO Work  
ALTALINK 30-Nov-19 07:30 03-Dec-19 18:00 3.44 Days
Continuous		 310p 240 kV C Bus, 138 kV Bus GOI Footings for new Station Service PTs, Add second bus protection to 240kV C Bus  
ATCO 30-Nov-19 08:00 30-Nov-19 17:00 9 Hours
Continuous		 7L702, 7L702 (137s Sedgewick - 757s Battle River) Change Arms and Insulators on 7L702  
ALTALINK 02-Dec-19 08:00 03-Dec-19 16:00 1.33 Days
Daily		 603L (138s - 243s) GOI, 603L (138s Windy Flats - 243s Soderglen Wind Farm) Install and test new tele-protection module that provides transfer tripping between 138s Windy Flats and 243s Soderglen  
Syncrude 02-Dec-19 08:00 08-Dec-19 20:00 6.5 Days
Continuous		 Significant outage - D05 Substation 260/72 kV Outage - Zone 4. Following Cicuit Breakers will operated: 222 (Aurora G01 Substation), 223 (Aurora G01 Substation), and 511, 512 at D05 Following MOD will be Operated: 225 (Aurora G01 Substation), and 514, 511A, 511B, 512A, 512B at D05. Significant outage - D05 Substation 260/72 kV Outage - Zone 4.
Following Cicuit Breakers will operated: 222 (Aurora G01 Substation), 223 (Aurora G01 Substation), and 511, 512 at D05

Following MOD will be Operated:
225 (Aurora G01 Substation), and 514, 511A, 511B, 512A, 512B at D05.		  
ATCO 02-Dec-19 08:00 09-Dec-19 17:00 7.38 Days
Continuous		 7L51, 7L51 (927s Buchanan Creek - A793s West Peace River) replace crossarms  
ALTALINK 02-Dec-19 08:45 20-Dec-19 17:15 18.35 Days
Continuous		 48s 887L/1L274 Open Breaker ADVICE for B, 887L (48s Pocaterra - BCH Britt Creek) Refurbishment project - replace structures and related components. (Placeholder)  
BCH 02-Dec-19 09:00 20-Dec-19 17:00 18.33 Days
Continuous		 1L274 (48s Pocaterra - Britt Creek) annual maintenance AB-BC
ALTALINK 02-Dec-19 10:00 05-Dec-19 15:00 3.21 Days
Continuous		 912L (63s-766s) - Advice, 912L (63s Red Deer - 766s Nevis) Migrate and commission all L7 –1082 at 63S Red Deer associated line protections, breakers, breaker fail and Tele-protection alarms, status, controls, metering and remote access to new RTU and LAN. Migrate and commission VT-7 alarms. Replace and commission new 63S1082 (1189) airbreak control module.  
ATCO 02-Dec-19 12:00 06-Dec-19 12:00 4 Days
Continuous		 7L73, 7L73 (730s Rycroft - 829s Boucher Creek) Line Maintenance  
ALTALINK 04-Dec-19 08:00 13-Dec-19 17:30 9.4 Days
Continuous		 19s T10, 138kV Bus 1, bus 2 and T8 GOI Salvage 138kv structure and switches 19s75 and 19s74. Replace 138kv insulators, relocate 19s7 and 19s240(will be in the same location)  
ALTALINK 06-Dec-19 09:00 06-Dec-19 13:00 4 Hours
Daily		 17s 240kV Bus 2 & 906L - GOI, 906L (17s Benalto - 42s Sarcee), 17s Benalto 240 kV South Bus 2 Replace 17s906X. Bus outage needed to disconnect 17s906X switch base from 906L.  
ALTALINK 06-Dec-19 09:15 06-Dec-19 13:45 4.5 Hours
Daily		 995L open end at 62s, 995L (62s Brazeau - 995AL tap) Radio work at 9062R. Loss of TPR requires line to be opened at 62s.  
ALTALINK 06-Dec-19 13:00 10-Dec-19 12:30 3.98 Days
Continuous		 17s906X (906L-42s) - GOI, 906L (17s Benalto - 42s Sarcee) Continue Replacing 17s906X Switch  
ALTALINK 09-Dec-19 07:30 11-Dec-19 16:30 2.38 Days
Continuous		 162.81L Enmax - Advice Replace line structure  
ENMAX 09-Dec-19 08:00 11-Dec-19 16:00 2.33 Days
Continuous		 162.81L, 162.81L (ENMAX 162 Beddington - 391S Balzac) Replace line structure.  
ATCO 09-Dec-19 08:30 10-Dec-19 17:00 1.35 Days
Continuous		 7L129, 7L129 (918s Bauer - 710s Vermilion) Line inspection of 7L129  
ALTALINK, EPCOR 09-Dec-19 09:15 13-Dec-19 18:15 4.38 Days
Continuous		 920L (37s - 557s) GOI, 920L (37s North Calder - 557s Castle Downs) Replace 240kV Switch (37s87), 240kV PTs (37s85)  
ATCO 09-Dec-19 12:00 13-Dec-19 12:00 4 Days
Continuous		 7L73, 7L73 (730s Rycroft - 829s Boucher Creek) Line Maintenance  
ALTALINK 10-Dec-19 13:00 10-Dec-19 17:00 4 Hours
Daily		 17s 240kV Bus 2 & 906L - GOI, 906L (17s Benalto - 42s Sarcee), 17s Benalto 240 kV South Bus 2 Replace 17s906X. Bus outage needed to Re-connect 17s906X switch base to 906L.  
ALTALINK 11-Dec-19 08:00 11-Dec-19 11:30 3.5 Hours
Daily		 67s12 Advice Line crew to close Open Point C  
ALTALINK 11-Dec-19 08:00 11-Dec-19 11:30 3.5 Hours
Daily		 67s97 Advice Line crew to close Open Point D  
ATCO 11-Dec-19 08:30 12-Dec-19 17:00 1.35 Days
Continuous		 7L129, 7L129 (526s Buffalo Creek - 918s Bauer) Line inspection of 7L129  
ALTALINK 11-Dec-19 11:00 11-Dec-19 15:00 4 Hours
Daily		 250p11 (250p Bighorn Plant) Maintenance  
ALTALINK 11-Dec-19 12:00 11-Dec-19 15:00 3 Hours
Daily		 67s820, 67sT2, 67s2 GOI disconnect mobile  
ALTALINK 12-Dec-19 09:00 12-Dec-19 13:00 4 Hours
Daily		 250p22 (250p Bighorn Plant) Maintenance  
ALTALINK, ATCO 12-Dec-19 10:00 12-Dec-19 15:00 5 Hours
Daily		 69s 138kV bus GOI(affecting 723L and 7L2, 723L (69s North Barrhead - 723L133), 7L230 (69s North Barrhead - 7L230 tap) A cable needs to be removed from the PT Secondary circuit connecting Panel #10 to Panel #11. Fuse blocks will also have to be removed. The cable that is to be removed shares terminals with the cable connected to the PT JB.  
ALTALINK 16-Dec-19 08:00 18-Dec-19 17:00 2.38 Days
Continuous		 67s3 GOI Maintenance  
ATCO 16-Dec-19 08:00 19-Dec-19 17:00 3.38 Days
Continuous		 7L32, 7L32 (811s Clairmont Lake - 862s South Bezanson), 7L32 (862s South Bezanson - 813s Little Smoky) replace crossarms  
ALTALINK 16-Dec-19 10:00 19-Dec-19 17:30 3.31 Days
Continuous		 310p 240 kV C Bus, 138 kV Bus GOI Install new Station Service PTs, complete second bus protection to 240kV C Bus  
ALTALINK 17-Dec-19 07:00 19-Dec-19 17:00 2.42 Days
Continuous		 71s452, 71s352 and 787L(71s - 71s787X) G, 787L (71s Lamoureux - 787L29) Replace 71s CT’s associated with breaker 71s452  
ALTALINK 17-Dec-19 08:30 17-Dec-19 17:00 8.5 Hours
Daily		 74s2152 - GOI Maintain 240kV SF6 breaker  
ATCO 17-Dec-19 09:00 17-Dec-19 15:00 6 Hours
Continuous		 6L126, 6L126 (515L tap - 743s Sarah Lake) Taking Wire samples for testing  
ALTALINK 18-Dec-19 23:00 19-Dec-19 03:00 4 Hours
Continuous		 62s 11 (62s Brazeau) Maintenance  
ALTALINK 19-Dec-19 03:00 19-Dec-19 07:00 4 Hours
Daily		 62s12 (62s Brazeau) Maintenance  
ATCO 20-Dec-19 08:00 22-Dec-19 17:00 2.38 Days
Continuous		 7L32, 7L32 (811s Clairmont Lake - 862s South Bezanson), 7L32 (862s South Bezanson - 813s Little Smoky) replace crossarms  
EPCOR, ALTALINK 06-Jan-20 07:00 05-Feb-20 17:00 30.42 Days
Continuous		 Isolation of 1139L from E816S Petrolia S/S and 376S Harry Smith S/S, 1139L (367s Harry Smith - 816s Petrolia) Cut in of 1139L and 1164L into Riverview S/S as part of Riverview energization.  
ATCO 06-Jan-20 08:00 13-Jan-20 15:00 7.29 Days
Continuous		 7L63, 7L63 (788s Hotchkiss - 783s Cadotte River) 7L63 crossarm replacements  
ALTALINK, EPCOR 06-Jan-20 08:00 05-Feb-20 18:00 30.42 Days
Continuous		 1139L (367s-E816s) GOI, 1139L (367s Harry Smith - 816s Petrolia) Cutting in EPCOR new sub (Riverview)  
ATCO 06-Jan-20 08:00 29-Feb-20 17:00 54.38 Days
Continuous		 7L64, 7L64 (930s Arcenciel - 7L64D5) Contractor replacing structures and crossarms  
ATCO 06-Jan-20 08:00 29-Feb-20 17:00 54.38 Days
Continuous		 7L59, 7L59 (789s Keg River - 7L59 tap) Contractor replacing structures and crossarms. This is a contingency outage taken only should 7L64 be unable to be taken out of service. 7L64 & 7L59 will not be taken out at the same time.  
ALTALINK 08-Jan-20 07:15 09-Jan-20 17:45 1.44 Days
Continuous		 320p1352 (1045AL) GOI Settings Changes of Sync Check and Functional Testing on 320p1352  
ENMAX, ALTALINK 13-Jan-20 08:00 14-Jan-20 16:00 1.33 Days
Continuous		 833L. 12PT138-Z31. 12.2TR, 833L (ENMAX 2 - ENMAX 12) HV SW maint SW81, SW82, SW83, MD-12.2TR  
ALTALINK 13-Jan-20 08:30 16-Jan-20 17:30 3.38 Days
Continuous		 511s SVC+ GOI, 511s SVC Plus (511s Crossings) Install snubber for SVC+ expansion tank sensors, yearly maintenance  
ENMAX, ALTALINK 14-Jan-20 08:00 15-Jan-20 16:00 1.33 Days
Continuous		 832L. 12PT138-Z31. 12.2TR, 832L (ENMAX 10 - ENMAX 12) HV SW maint SW84, SW85, SW86, MD-12.1TR  
ALTALINK 14-Jan-20 08:45 24-Jan-20 17:15 10.35 Days
Continuous		 48s 887L/1L274 Open Breaker ADVICE for B, 887L (48s Pocaterra - BCH Britt Creek) Refurbishment project - replace structures and related components. (Placeholder)  
ATCO 20-Jan-20 08:00 27-Jan-20 15:00 7.29 Days
Continuous		 7L63, 7L63 (788s Hotchkiss - 783s Cadotte River) 7L63 crossarm replacements  
ATCO 20-Jan-20 08:00 03-Feb-20 16:00 14.33 Days
Continuous		 740S 701 Replace BKR 701, replace 701PT
 
ALTALINK 28-Jan-20 07:15 29-Jan-20 17:45 1.44 Days
Continuous		 788L (788L107A-A898s-602L1) - GOI, 788L (898s Heart Lake - 788L107A - 602L1) 788L Components Str's Range 151-282  
ATCO 31-Jan-20 09:00 13-Mar-20 16:00 42.25 Days
Continuous		 807s 902T (807s Sheerness), 9L100, 807S 902, 9L100 (801s Anderson - 807s Sheerness) 794L Components Str's Range 9-258, 807S BKR 902 maintenance & 9L100 protection upgrade
Work has been coordinated with ATCO Power and it was stated that 807S unit #2 Shutdown will occur from Jan 31 to March 13, 2020, outages are dependant on 807S unit 2 shutdown
Outage zone needs to expand from 9100D1 to 910B & 911B to include 910 & 911 for testing		  
ATCO 03-Feb-20 08:00 10-Feb-20 17:00 7.38 Days
Continuous		 7L63, 7L63 (788s Hotchkiss - 783s Cadotte River) 7L63 crossarm replacements  
ATCO 03-Feb-20 08:00 16-Feb-20 16:00 13.33 Days
Continuous		 740S 704, 7L20, 7L20 (810s Dome Cutbank - 740s H.R.Milner) replace breaker and re conductor switches  
ENMAX 03-Feb-20 08:00 01-Mar-20 16:00 27.33 Days
Continuous		 162.81L, 162.81L (ENMAX 162 Beddington - 391S Balzac) Line Protection Upgrade  
ALTALINK 03-Feb-20 12:15 06-Feb-20 17:45 3.23 Days
Continuous		 794L (157s-A819s) - GOI, 794L (157s Lac La Biche - 819s Whitby Lake) 794L Components Str's Range 9-258  
ENMAX 04-Feb-20 08:00 04-Feb-20 16:00 8 Hours
Continuous		 162.81L, 162.81L (ENMAX 162 Beddington - 391S Balzac) HV SW maint SW82, SW83, MD-162.1TR  
ENMAX, ALTALINK 05-Feb-20 08:00 06-Feb-20 16:00 1.33 Days
Continuous		 918L, 918L (281s Johnson - 162s Beddington) HV SW maint SW134, SW135, MD-918  
ENMAX, ALTALINK 10-Feb-20 08:00 10-Feb-20 16:00 8 Hours
Continuous		 932L, 932L (74s Janet - 162s Beddington) HV SW maint SW144, SW145  
ALTALINK 10-Feb-20 12:15 13-Feb-20 17:45 3.23 Days
Daily		 794L (157s-A819s) - GOI, 794L (157s Lac La Biche - 819s Whitby Lake) Component Replacements STR 9-258  
EPCOR 17-Feb-20 07:00 15-May-20 17:00 88.38 Days
Continuous		 TX1 @ Bellamy Transformer Regasketing  
ATCO 17-Feb-20 08:00 21-Feb-20 16:00 4.33 Days
Continuous		 951S SVC, 951s SVC (951s Thickwood) Plans to close-out deficiencies identified after commissioning of the Thickwood SVC,


Require study early Jan 2020		  
ATCO 18-Feb-20 08:00 24-Feb-20 17:00 6.38 Days
Continuous		 7L63, 7L63 (788s Hotchkiss - 783s Cadotte River) 7L63 crossarm replacements  
ALTALINK 18-Feb-20 12:15 20-Feb-20 17:45 2.23 Days
Continuous		 794L (157s-A819s) - GOI, 794L (157s Lac La Biche - 819s Whitby Lake) Component Replacements STR 9-258  
ALTALINK 25-Feb-20 08:00 27-Feb-20 17:45 2.41 Days
Continuous		 794L (157s-A819s) - GOI, 794L (157s Lac La Biche - 819s Whitby Lake) 794L Components Replacements Str's 9-258  
ALTALINK 02-Mar-20 12:15 05-Mar-20 17:45 3.23 Days
Continuous		 794L (157s-A819s) - GOI, 794L (157s Lac La Biche - 819s Whitby Lake) 794L Components Replacements Str's 9-258  
ATCO 06-Mar-20 07:00 13-Mar-20 17:00 7.38 Days
Continuous		 9L101, 9L101 (2005s Secord - 957s McClelland) Line move for mine expansion.
Attach new line to existing 9L101		  
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.  
ENMAX, ALTALINK 06-Apr-20 08:00 17-Apr-20 18:00 11.42 Days
Continuous		 36.81L., 36.81L (44s Bearspaw - ENMAX 36) Haskayne line raise project. Raising the line and replacing 4 structures to accommodate a new road construction.  
ATCO 02-Jul-20 08:00 15-Jul-20 16:00 13.33 Days
Continuous		 7L587, 7L587 (826s Marguerite Lake - 822s Wolf Lake) 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ATCO 16-Jul-20 08:00 29-Jul-20 16:00 13.33 Days
Continuous		 7L89, 7L89 (826s Marguerite Lake - 721s La Corey), 7L89 (721s La Corey - 700s Bonnyville) 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ATCO 30-Jul-20 08:00 12-Aug-20 16:00 13.33 Days
Continuous		 7L91 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ATCO 03-Aug-20 07:00 03-Nov-20 17:00 92.46 Days
Continuous		 972S 905B Halkirk 2 Windfarm Project  
ATCO 03-Aug-20 08:00 05-Aug-20 16:00 2.33 Days
Continuous		 RL1, 848S 902T, 848S 900BS2 848S Ruth Lake 240kv expansion for 29PL9-26 tie in

AUG 3, 2020 - AUG 5, 2020
GOI points:912B,RL-1D1,901A,905A,902TD
Impact: 900BS2 & 902T OOS, RL1 open ended
Scope: remove low pipe bus		  
ATCO 05-Aug-20 08:00 04-Sep-20 16:00 30.33 Days
Continuous		 848S 911, 848S 240kV BUS 848S Ruth Lake 240kv expansion for 29PL9-26 tie in

AUG 5 2020 - SEPT 4 2020
SHRINK GOI to: 911B,912B
Impact: 911 OOS
Scope: install breaker 912, switches & PT's		  
ALTALINK 11-Aug-20 08:00 11-Aug-20 18:00 10 Hours
Daily		 861L(258s-71s) and 258s 138kV Bus 2 GOI Replacement of 861L Strain Insulators at 258s. Remove Bus #2 from service as line crosses 138kV Bus.  
ALTALINK 11-Aug-20 08:00 11-Aug-20 19:00 11 Hours
Daily		 862L(258s-166s) and 258s 138kV Bus 1 GOI Replacement of 862L Strain Insulators at 258s. Remove Bus #1 from service as line crosses 138kV Bus.  
ATCO 13-Aug-20 08:00 26-Aug-20 16:00 13.33 Days
Continuous		 9L36 240/144kV Breaker Fail Protection
(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  
ATCO 27-Aug-20 08:00 09-Sep-20 16:00 13.33 Days
Continuous		 9L37 240/144kV Breaker Fail Protection
(OOS for duration of outages)

826S Marguerite P&C Upgrade		  
ATCO 04-Sep-20 08:00 06-Sep-20 16:00 2.33 Days
Continuous		 848S 901T, 9L01, 848S 900BS1 848S Ruth Lake 240kv expansion for 29PL9-26 tie in

SEPT 4 2020 - SEPT 6 2020
EXPAND GOI to: 911B,9L01D1,908A,903A,901TD
Impact: 900BS1 & 901T OOS, 9L01 open ended
Scope: remove low pipe bus		  
ATCO 06-Sep-20 08:00 10-Nov-20 16:00 65.38 Days
Continuous		 848S 911, 848S 240kV BUS 848S Ruth Lake 240kv expansion for 29PL9-26 tie in

SEPT 6 2020 - NOV 10 2020
SHRINK GOI to: 911B,912B
Impact: 911 OOS
Scope: continue to install breaker 912, switches & PT's		  
ATCO 10-Sep-20 08:00 01-Oct-20 16:00 21.33 Days
Continuous		 826S 901T 240/144kV Breaker Fail Protection
(901T OOS for duration of outages)

826S Marguerite P&C Upgrade		  
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  
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		  
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		  
ATCO 02-Oct-20 08:00 23-Oct-20 16:00 21.33 Days
Continuous		 826S 902T 240/144kV Breaker Fail Protection
(902T OOS for duration of outages)

826S Marguerite P&C Upgrade		  
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  
ATCO 22-Oct-20 07:00 27-Oct-20 17:00 5.42 Days
Continuous		 7L65, 7L77 7L65 Rebuild Project  
ATCO 10-Nov-20 08:00 12-Nov-20 16:00 2.33 Days
Continuous		 RL1, 848S 902T, 848S 900BS2 848S Ruth Lake 240kv expansion for 29PL9-26 tie in

NOV 10, 2020 - NOV 12, 2020
EXPAND GOI to: 912B,RL-1D1,901A,905A,902TD
Impact: 900BS2 & 902T OOS, RL1 open ended
Scope: install low pipe bus		  
ATCO 12-Nov-20 08:00 13-Nov-20 16:00 1.33 Days
Continuous		 848S 911, 848S 240kV BUS 848S Ruth Lake 240kv expansion for 29PL9-26 tie in

NOV 12 2020 - NOV 13 2020
SHRINK GOI to: 911B,912B
Impact: 911 OOS
Scope: continue to install breaker 912, switches & PT's		  
ATCO 13-Nov-20 08:00 15-Nov-20 16:00 2.33 Days
Continuous		 848S 901T, 9L01, 848S 900BS1 848S Ruth Lake 240kv expansion for 29PL9-26 tie in

NOV 13 2020 - NOV 15 2020
EXPAND GOI to: 911B,9L01D1,903A,908A,901TD
Impact: 900BS1 & 901T OOS, 9L01 open ended
Scope: install low pipe bus		  
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 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  

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: 2019-11-13   3:05:07 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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