Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2023-06-03

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:
it affects a transmission facility operating at two hundred and forty (240) kV or greater; it affects an intertie; it affects an element connecting facilities owned by two (2) or more different legal owners of transmission facilities; it affects an element that connects a generating unit or an aggregated generating facility to the interconnected electric system; it requires the ISO to issue a dispatch or directive for generation in order to facilitate the planned outage; it affects a cutplane limit; it limits or reduces the operability of a synchronous condenser, static VAr compensator, static compensator or other similar dynamic device; or 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
ATCO	17-Apr-23 10:00	05-Jun-23 16:00	49.25 Days Continuous	740s 701 (740s H.R. Milner), 740s 701B (740s H.R. Milner)	replace damaged switch arm on 701B
Syncrude	24-Apr-23 08:00	12-Jun-23 20:00	49.5 Days Continuous	T4 (Aurora)	maintenance
ATCO	18-May-23 13:00	08-Jun-23 17:00	21.17 Days Continuous	7L113 (853s Ring Creek - 930s Arcenciel)	repair damaged structures due to wildfire
ENMAX, ALTALINK	23-May-23 08:01	08-Jun-23 13:00	16.21 Days Continuous	240kV West Bus (SS-25), 1080L (SS-25 - SS-65), 25B240-D138 (SS-25), 25B240-D139 (SS-25), 25B240-D142 (SS-25), 25B240-D133 (SS-25), 25B240-D136 (SS-25), 25MD240-1080 (SS-25), 65MD240-1080 (SS-65)	Expansion of GOI Zone for Urgent work to replace 1080L cables into C25s for scaffolding for cable terminations
ATCOP, CNRL	28-May-23 07:30	04-Jun-23 18:00	7.44 Days Continuous	838s 75-TR-2701 (838s Horizon Mining), 838s 75-BC-1917 (838s Horizon Mining), 838s 75-BC-1918 (838s Horizon Mining)	protective relay testing
CNRL, ATCOP	28-May-23 07:30	05-Jun-23 18:00	8.44 Days Continuous	75-PLH-903 (838s Horizon Mining - 842s Horizon Upgrading), 842s 75-TR-4701 (842s Horizon Upgrading), 842s 75-TR-7701 (842s Horizon Upgrading), 838s 75-BC-1911 (838s Horizon Mining), 838s 75-BC-1918 (838s Horizon Mining), 842s 75-1902 (842s Horizon Upgrading), 842s 75-1902A (842s Horizon Upgrading), 842s 75-1903 (842s Horizon Upgrading), 842s 75-1903A (842s Horizon Upgrading), 842s 75-1903B (842s Horizon Upgrading), 842s 75-4701 (842s Horizon Upgrading), 842s 75-1904 (842s Horizon Upgrading), 842s 75-1904A (842s Horizon Upgrading), 842s 75-1904B (842s Horizon Upgrading), 842s 75-7701 (842s Horizon Upgrading), 842s 75-1905 (842s Horizon Upgrading), 842s 75-1905A (842s Horizon Upgrading)	260kV 5YR PMs and Protective Relay Upgrades
ATCO	28-May-23 17:01	11-Jun-23 17:00	14 Days Continuous	9L09 (849s Joslyn Creek - 888s Dover), 849s 902 (849s Joslyn Creek), 849s 903 (849s Joslyn Creek)	849s 9L09 protection upgrades
BCH	29-May-23 09:00	09-Jun-23 17:00	11.33 Days Continuous	T3 (BCH Natal)	Tap changer inspections and doble testing	AB-BC
ATCO, ALBIAN	30-May-23 08:00	03-Jun-23 16:00	4.33 Days Continuous	920s 901T (920s Jackpine), 9LJH1 (919s Hartley - 920s Jackpine)	repairs on failed 72kV cable from 901T
SUNCOR	30-May-23 08:00	03-Jun-23 20:00	4.5 Days Continuous	29PL9-3 (29EDD-1 Millennium - 29EDD-3)	Millennium 260kV bus jumper replacement related to existing 29PL9-3
ALTALINK	02-Jun-23 21:00	04-Jun-23 20:00	1.96 Days Continuous	38s T1, 138kV Bus 1, & 293s - GOI, 38s T1 (38s East Edmonton), 38s C1 (38s East Edmonton), 38s C2 (38s East Edmonton), 737L (38s East Edmonton - 95s Imperial Oil Edmonton), 736L (38s East Edmonton - 293s Bernese), 865L (38s East Edmonton - 216s Knightsbridge)	Replace 38s736CT’s, replace insulators on 7 switches and 15 post insulators and perform transformer maintenance on 293sT1 and 293sT2.
ENMAX, ALTALINK	03-Jun-23 08:00	03-Jun-23 18:00	10 Hours Continuous	24.81L (SS-24 - SS-31). 24.83L (74s Janet - SS-24), 24B138-24BT3 (SS-24), 24.1TR (SS-24), 24.81L (SS-24 - SS-31), 24.83L (74s Janet - SS-24)	Power factor test 24B138-24.81-CT, 24B138-24BT3-CT
ALTALINK	03-Jun-23 09:00	03-Jun-23 17:00	8 Hours Daily	33s 6 (33s Spray)	Maintenance
EPCOR, ALTALINK	04-Jun-23 07:00	04-Jun-23 17:00	10 Hours Continuous	1056L @ Argyll Transfer Station E629S and Ellerslie 89S, 1056L (89s Ellerslie - 629s Argyll Transfer Station)	1056L: Aerial- Washing Program (Spring)
SUNCOR	05-Jun-23 06:00	18-Jun-23 18:00	13.5 Days Continuous	29PL9-14, 29PL9-14 (29EDD-34 - 29EDD-56)	29PL9-14@29EDD34
ALTALINK	05-Jun-23 07:00	05-Jun-23 18:00	11 Hours Daily	707L (54s-166s) - GOI, 707L (54s Fort Saskatchewan - 166s Dow Chemical Fort Saskatchewan)	FRM component replacement 707L (str 1-35)
EPCOR, ALTALINK	05-Jun-23 07:00	13-Jun-23 17:00	8.42 Days Continuous	Genesee S/S 430L Bay Isolation, 430L (330P Genesee - 510S Sunnybrook)	138kv 430L1 & L2 foundation installation
EPCOR	05-Jun-23 07:00	16-Jun-23 17:00	11.42 Days Continuous	TX1 Zone @ Bellamy E814S, 814s T1 (814s Bellamy)	Bellamy: Apparatus First Week- TX1 Doble and Arrestor/PT Doble, P&C Second Week- TX1 Zone P&C Maintenance
EPCOR	05-Jun-23 07:00	16-Jun-23 17:00	11.42 Days Continuous	TX3 @ Lambton E803S, EP 803s T3 (EP 803s Lambton)	Lambton: TX3 DGA Installation and Neutral Bushing Replacement
ALTALINK	05-Jun-23 07:30	07-Jun-23 12:30	2.21 Days Continuous	510s ACF 12 – GOI, 510s ACF12 (510s Sunnybrook)	Filter bank inspection, Breaker Dashpot Inspection, 6MD66 relay maintenance
ALTALINK	05-Jun-23 08:00	08-Jun-23 16:00	3.33 Days Continuous	511s AC Filter Bank 1 and T30 - GOI, AML 511s FB Bus 1 (AML 511s Crossings), AML 511s T30 (AML 511s Crossings)	Annual ACF 11, 12, 13 Inspections, Bird Mitigation on Reactors in Filter. SVC Plus will also be out of service.
ENMAX	05-Jun-23 08:00	16-Jun-23 18:00	11.42 Days Continuous	162.1TR (SS-162)., 162.1TR (SS-162)	Power factor test transformer. Transformer Maintenance. Power Factor Test - 162PT138-T1. Transformer Monitor Maintenance. Tap changer maintenance. 162.1TR-oil monitor leaks in cabinet
FMGW, SUNCOR	05-Jun-23 08:00	30-Jun-23 18:00	25.42 Days Continuous	29PT-239 29PT-234, 29EDD-71 29PT-234 (29EDD-71)	FB - 29EDD71;144KV NODE,29PT-239 MAINT;PM 5y 29EDD71;29PT-234 & 30PD-16 MAINT;PM 5y 29EDD71;29-752-4621 MAINT & TEST;PM 10y 29EDD71;29-752-4622 MAINT & TEST;PM 10y
ATCO	05-Jun-23 08:30	10-Jun-23 12:30	5.17 Days Continuous	7L01, 881S 701T, 881S 702T, 7L01 (813s Little Smoky - 881s Sturgeon 2), 881s 701T (881s Sturgeon), 881s 702T (881s Sturgeon)	Switching 7L01 Temp to switch out 701T and 702T to perform Maintenance on equipment. June 5 08:30, 2023 - 813S OPEN 711 and 712 to de-energize 7L01 - 881S OPEN 701TD - 813S CLOSE 711 and 712 June 8 08:30 - 813S OPEN 711 and 712 to de-energize 7L01 - 881S CLOSE 701TD - 881S OPEN 702TD - 813S CLOSE 711 and 712 June 10, 12:30 - 813S OPEN 711 and 712 to de-energize 7L01 - 881S CLOSE 702TD - 813S CLOSE 711 and 712
EPCOR, ALTALINK	05-Jun-23 09:30	16-Jun-23 17:00	11.31 Days Continuous	908LW (East ind TX2) East Industrial E52S and East Edmonton 38S and Ellerslie 89S, 908L (38s East Edmonton - 908AL tap), 908L (89s Ellerslie - 908AL tap), 908AL (52S East Industrial - 908L tap), 89s 852 (89s Ellerslie), 89s 752 (89s Ellerslie), 52s T2 (52s East Industrial), 38s 7652 (38s East Edmonton), 38s 7552 (38s East Edmonton)	East Industrial: P&C Telecom Upgrade w/AltaLink
Saskpower	05-Jun-23 10:00	09-Jun-23 18:00	4.33 Days Continuous	SASK POWER P2C	maintenance	AB-SK
ATCO	05-Jun-23 12:00	08-Jun-23 16:00	3.17 Days Continuous	876S 240kV Breaker Relays, 876S 9L10 Protection Relay, 9L10, 876S 901, 876S 903, 9L10 (876s Brintnell - 939s Livock), 876s 901 (876s Brintnell), 876s 903 (876s Brintnell)	21A&B/ 9L10, 50BF/901&903 RTXP Test Switch Replacement, PRC-005 Relay Testing 21A&B / 9L10 an 50BF/ Bkr 901&903, PRC-005 Trip Coil Testing Breaker 901 & 903
ATCO	05-Jun-23 12:00	09-Jun-23 17:30	4.23 Days Continuous	951S SVS, 951s SVC (951s Thickwood)	SVS outage Semi annual Inspection
ALTALINK	06-Jun-23 07:00	06-Jun-23 18:00	11 Hours Daily	787L (71s-787L29) - GOI, 787L (71s Lamoureux - 787AL tap)	FRM component replacement 787L (Str 14-26)
CNRL	06-Jun-23 07:30	09-Jun-23 18:00	3.44 Days Continuous	838s 75-TR-2801 (838s Horizon Mining)	Protective Relay Testing
ALTALINK	06-Jun-23 08:00	06-Jun-23 16:00	8 Hours Daily	121s T2 (121s Brooks)	Remove old bird cover from 25kv bushings on T2 transformer. Install new bird cover on 25kV bushings, T-connectors and 25kV risers.
ATCO	06-Jun-23 08:00	06-Jun-23 17:00	9 Hours Continuous	Coyote lake_S-Telecom	Replace existing Coyote Lake SAR Node ID 169.1. A new chassis and cards will be installed
ALTALINK	06-Jun-23 08:00	08-Jun-23 13:00	2.21 Days Continuous	39sT1 (Tx18107) – GOI, 39s T1 (39s Bickerdike)	Transformer maintenance, fix temp gauge, oil leak, 29GT relocate.
ATCOP, CNRL	06-Jun-23 08:00	09-Jun-23 18:30	3.44 Days Continuous	838s 75-TR-1801 (838s Horizon Mining)	Protective Relay Testing, CVT 5YR PM
ALTALINK	06-Jun-23 10:00	06-Jun-23 12:00	2 Hours Daily	632s 412 (632s Russell), 412L (396s Pincher Creek - 632s Russell)	1st Trip followed by maintenance	AB-BC
ALTALINK	07-Jun-23 07:00	07-Jun-23 18:00	11 Hours Daily	787L (166s-787L33) - GOI, 787L (166s Dow Chemical Fort Saskatchewan - 787AL tap)	FRM component replacement 787L (Str 37-39)
ALTALINK	07-Jun-23 08:00	07-Jun-23 16:00	8 Hours Daily	121s T5 (121s Brooks)	Remove old bird cover from 25kv bushings on T5 transformer. Install new bird cover on 25kV bushings, T-connectors and 25kV risers.
BCH	07-Jun-23 09:00	07-Jun-23 17:00	8 Hours Continuous	1L274 (B1s BCH Natal - 1D1L274)	replace timbers	AB-BC
ALTALINK	07-Jun-23 09:30	07-Jun-23 17:30	8 Hours Daily	42s70 - GOI, 42s 70 (42s Sarcee)	PRC5 1st Trip Breaker Maintenance and Cab Thermostat repair
ALTALINK	07-Jun-23 09:30	07-Jun-23 17:30	8 Hours Daily	103s452 - GOI, 103s 452 (103s Goose Lake)	1st Trip PRC5
ALTALINK	07-Jun-23 12:30	09-Jun-23 16:30	2.17 Days Continuous	510s ACF 11 – GOI, 510s ACF11 (510s Sunnybrook)	Filter bank inspection, Breaker Dashpot Inspection, 6MD66 relay maintenance
ENMAX, ALTALINK	08-Jun-23 08:00	08-Jun-23 16:00	8 Hours Continuous	36.81L (44s Bearspaw Plant - SS-36)	Power factor test 36B138-36.81-CT
ALTALINK	08-Jun-23 09:00	08-Jun-23 16:30	7.5 Hours Daily	753L (65s High River - 253s Blackie), 253s 753W (253s Blackie)	change one grading capacitor and replace a cabinet heater
BCH	08-Jun-23 09:00	08-Jun-23 17:00	8 Hours Continuous	1L274 (EFT - 1D2L274)	replace structures and timbers	AB-BC
BCH	08-Jun-23 10:00	08-Jun-23 16:00	6 Hours Continuous	2L112 (BPA Boundary - BCH Nelway)	END-TO-END TRIP CHECKS WITH BC HYDRO	AB-BC
Saskpower	09-Jun-23 19:00	15-Jun-23 18:00	5.96 Days Continuous	SaskPower A1R	planned outage	AB-SK
EPCOR	12-Jun-23 07:00	12-Jun-23 17:00	10 Hours Continuous	TX2 @ Summerside E657S, 657s T2 (657s Summerside)	Summerside: SU2T2 Repair (WO: 043789)
EPCOR	12-Jun-23 07:00	17-Jun-23 17:00	5.42 Days Continuous	J2408 (J240C1) @ Jasper Terminal E805S, EP 805s J2408 (EP 805s Jasper)	Jasper: J2408 Breaker Maintenance and CT/CVT/PT/Arrestor Doble and JDS13GS Disconnect Maintenance
ALTALINK	12-Jun-23 08:00	15-Jun-23 16:00	3.33 Days Continuous	511s ACF Bank # 2 GOI, AML 511s FB Bus 2 (AML 511s Crossings)	Annual ACF 21, 22 Inspections, Bird Mitigation on Reactors in Filter
BCH	12-Jun-23 09:00	23-Jun-23 17:00	11.33 Days Continuous	T4 (BCH Natal)	Replace NTL 2CT2	AB-BC
ATCO	12-Jun-23 09:30	30-Jun-23 17:30	18.33 Days Continuous	2075s ACF11 (2075s Newell), 2075s ACF12 (2075s Newell), 2075s ACF13 (2075s Newell), 2075s ACF14 (2075s Newell)	PRC-005 testing, filter bank inspections, & HMI Upgrades
ATCO	12-Jun-23 10:00	16-Jun-23 14:00	4.17 Days Continuous	856s 902T (856s Kinosis), 856S 701	902T Maintenance, 701 Maintenance
ALTALINK	12-Jun-23 10:30	12-Jun-23 17:30	7 Hours Daily	370s852 - GOI, 370s 852 (370s North Lethbridge)	1st Trip PRC5 Breaker Maintenance
ALTALINK	12-Jun-23 11:00	15-Jun-23 17:30	3.27 Days Continuous	63s952 GOI, 63s 952 (63s Red Deer)	240kV breaker maintenace
ENMAX, ALTALINK	12-Jun-23 12:00	12-Jun-23 18:00	6 Hours Continuous	37.82L (74s Janet - SS-37), 37.2TR (SS-37)	Summer Substation Washing
ATCO	12-Jun-23 13:00	15-Jun-23 16:00	3.13 Days Continuous	7L224, 7L224 (650s Hansman Lake - 774s Monitor)	Cross arm and insulator replacement on 7L224
ALTALINK	12-Jun-23 13:00	15-Jun-23 17:00	3.17 Days Continuous	89s952 - GOI, 89s 952 (89s Ellerslie)	1st trip & PRC5 full maintenance
ALTALINK, BHE Canada	13-Jun-23 09:30	13-Jun-23 17:30	8 Hours Daily	120s152 - GOI, 120s 152 (120s Picture Butte)	1st Trip PRC5 Breaker Maintenance
ENMAX, ALTALINK	14-Jun-23 08:00	14-Jun-23 12:00	4 Hours Continuous	1106L (237s Foothills - SS-65), 1106L (237s Foothills - SS-65)	Summer Substation Washing
ALTALINK, BHE Canada	14-Jun-23 09:30	14-Jun-23 17:30	8 Hours Daily	120s252 - GOI, 120s 252 (120s Picture Butte)	1st Trip PRC5 Breaker Maintenance
ATCO	14-Jun-23 09:30	15-Jun-23 16:00	30.5 Hours Continuous	969S 301, 969S 701T, 969S 501, 969s 701T (969s Lindbergh)	701T Maintenance, and leak repairs 301 Close latch repairs
ALTALINK	14-Jun-23 12:00	14-Jun-23 18:00	6 Hours Continuous	1107L (237s Foothills - SS-65)	Summer Substation Washing
EPCOR	15-Jun-23 07:00	16-Jun-23 17:00	1.42 Days Continuous	TX1 Expanded Zone (240BA2 Open Ended) @ Bellamy E814S and Argyll Transfer Station E629S, 814s T1 (814s Bellamy), 240BA2 (629s Argyll Transfer Station - 814s Bellamy)	Bellamy: TX1 Zone P&C Maintenance and Op Checks
EPCOR	15-Jun-23 07:00	16-Jun-23 17:00	1.42 Days Continuous	TX3 Zone @ Lambton E803S, EP 803s T3 (EP 803s Lambton)	Lambton: Pole Lighting Upgrade Project (Pole #4, 5, 6)
ENMAX	15-Jun-23 08:00	15-Jun-23 18:00	10 Hours Continuous	65.1TR (SS-65)	Summer Substation Washing
ALTALINK, BHE Canada	15-Jun-23 09:30	15-Jun-23 17:30	8 Hours Daily	120s452 - GOI, 120s 452 (120s Picture Butte)	1st Trip PRC5
ALTALINK, ATCO	15-Jun-23 11:30	15-Jun-23 14:30	3 Hours Daily	395s77E (7L77) – GOI, 7L77 (395s North Holden - 709s Vegreville), 395s 77E (395s North Holden)	Commission new T1 tripping module trips to 395s77E (252). Commissioning of new SCADA alarms, controls, and metering.L2 A21/L2, B21/L2, & 11(96/25SC/79)/252 protections will be out of service at 395s.
ENMAX, ALTALINK	16-Jun-23 08:00	16-Jun-23 12:00	4 Hours Continuous	833L (SS-2 - SS-12). 12.2TR (SS-12), 833L (SS-2 - SS-12)	Summer Substation Washing
ENMAX, ALTALINK	16-Jun-23 12:00	16-Jun-23 18:00	6 Hours Continuous	832L (SS-10 - SS-12). 12.1TR (SS-12), 832L (SS-10 - SS-12)	Summer Substation Washing
ENMAX	17-Jun-23 08:00	17-Jun-23 13:00	5 Hours Continuous	25PT240-Z42 240kV Bus, 240kV West Bus (SS-25), 25B240-D142 (SS-25), 25B240-D139 (SS-25), 25B240-D136 (SS-25), 25B240-D133 (SS-25)	Summer Substation Washing. Z42, D133, D136, D142
ENMAX	17-Jun-23 13:00	17-Jun-23 18:00	5 Hours Continuous	25PT240-Z41 240kV Bus, 240kV East Bus (SS-25), 25B240-D140 (SS-25), 25B240-D138 (SS-25), 25B240-D134 (SS-25), 25B240-D131 (SS-25)	Summer Substation Washing. Z41, D131, D134, D140
ATCO	19-Jun-23 06:00	23-Jun-23 16:00	4.42 Days Continuous	7LA128, 7LA128 (572s Highland - 7L128 tap)	The outage is to remove the temporary 144kV breaker at the Highlands substation and install the correct 144kV POW breaker, as well as installation of the station SST.
SUNCOR	19-Jun-23 06:00	02-Jul-23 18:00	13.5 Days Continuous	29PL9-15, 29PL9-15 (29EDD-34 - 29EDD-56)	29PL9-15@29EDD34
ENMAX	19-Jun-23 08:00	19-Jun-23 18:00	10 Hours Continuous	65.2TR (SS-65)	Summer Substation Washing
ENMAX	19-Jun-23 08:00	30-Jun-23 18:00	11.42 Days Continuous	162.2TR (SS-162)., 162.2TR (SS-162)	Power factor test transformer. Transformer Maintenance. Power Factor Test - 162PT138-T2. Transformer Monitor Maintenance. Tap changer maintenance. 162.2TR Hot Spot (Low Side Riser)
ATCO	19-Jun-23 09:30	23-Jun-23 17:30	4.33 Days Continuous	2029S ACF11, 2029S ACF12, 2029S ACF13, 2029S ACF14, 2029s ACF11 (2029s Heathfield), 2029s ACF12 (2029s Heathfield), 2029s ACF13 (2029s Heathfield), 2029s ACF14 (2029s Heathfield)	PRC-005 testing, filter bank inspections
EPCOR, ALTALINK	19-Jun-23 09:30	30-Jun-23 17:00	11.31 Days Continuous	1059L (TX1 East Ind) @ Lambton E803S and East Industrial E52S and East Edmonton 38S, 1059AL (52s East Industrial - 1059L tap), 1059L (38s East Edmonton - 1059AL tap), 1059L (EP 803s Lambton - 1059AL tap)	East Ind: P&C- Telecom Upgrade w/ AltaLink. Lambton: 1059L CT/Arrestor Doble and LDS1/LDS8 Disconnect Maintenance, and Lambton Pole Lighting Upgrade Project (Pole #2 on June 23) and East Industrial: E2401 Breaker Maintenance and CVT Doble
ATCO	19-Jun-23 10:00	23-Jun-23 16:00	4.25 Days Continuous	813S SVC, 813s SVC (813s Little Smoky)	SVC maintenance
ALTALINK	19-Jun-23 12:00	22-Jun-23 18:00	3.25 Days Continuous	86s T1 (86s Bigstone)	Major tap changer maintenance, monitor alarm investigate, test, install bushing monitors
ALTALINK	19-Jun-23 12:00	22-Jun-23 18:00	3.25 Days Continuous	562s T2 (562s Cypress)	PRC5 doble and maintenance
ALTALINK, ENEL	21-Jun-23 07:30	23-Jun-23 13:30	2.25 Days Continuous	205s T2 (205s Castle Rock Ridge), 205s 14 (205s Castle Rock Ridge)	maintenance
ENMAX, ALTALINK	21-Jun-23 08:00	21-Jun-23 13:00	5 Hours Continuous	985L (74s Janet - SS-25)	Summer Substation Washing. D133, D132, MD-985
ATCO	21-Jun-23 08:30	22-Jun-23 17:30	1.38 Days Continuous	802S 706, 7L171, 7L171 (802s Michichi Creek - 804s Wintering Hills), 802s 706 (802s Michichi Creek)	BREAKER 706 SF6 LTB145D1/B COMPLETE TESTING
ATCO, SUNCOR	21-Jun-23 09:30	14-Aug-23 16:00	54.27 Days Continuous	848S 29PL9-2 Protection Relay, 848S 901, 848S 902, 29PL9-2, 848s 901 (848s Ruth Lake), 29PL9-2 (29EDD-1 Millennium - 848s Ruth Lake), 848s 902 (848s Ruth Lake)	Suncor Capacity Increase project. Suncor is reconductoring 29PL9-2, ATCO is completing a line protection upgrade in coordination with the outage
ALTALINK	21-Jun-23 12:00	21-Jun-23 18:00	6 Hours Continuous	1003L (74s Janet - SS-25)	Summer Substation Washing. D136, D135, MD-1003
ALTALINK	22-Jun-23 08:00	22-Jun-23 13:00	5 Hours Continuous	1109L (SS-25 - SS-65)	Summer Substation Washing 25sub 25MD240-1109
ENMAX, ALTALINK	24-Jun-23 08:00	25-Jun-23 18:00	1.42 Days Continuous	771L (SS-47 - SS-162), 47.1TR (SS-47), 47.2TR (SS-47), 162B138-RB82 (SS-162), 162B138-RB81 (SS-162)	HV SW Maint. SW81, SW86. Summer substation washing. Oil Sampling 47.2-MT, TC. Power factor test 162PT138-771. Surge Arrestor Power Factor Test - 162MD138-771L
ATCO	25-Jun-23 08:00	30-Jun-23 12:00	5.17 Days Continuous	7L32 (811s Clairmont Lake - 862s South Bezanson)	Pole replacement on 7L32 GOI
EPCOR	26-Jun-23 07:00	28-Jun-23 17:00	2.42 Days Continuous	P2402 @ Petrolia E816S, 816s P2402 (816s Petrolia)	Petrolia: P2402 CT Doble
EPCOR	26-Jun-23 07:00	28-Jun-23 17:00	2.42 Days Continuous	SU2404 @ Summerside E657S, 657s SU2404 (657s Summerside)	Summerside: SU2404 Breaker Maintenance and CT Doble
Syncrude	26-Jun-23 08:00	27-Jun-23 20:00	1.5 Days Continuous	Significant Outage: Require outage to replace the motor on MOD 520 in D05 substation. The following motor operated disconnect switches will be operated: 519B @ D05 Substation 520 @ D05 Substation 517A @ D05 Substation 215 @ G01 Substation, AL-1 (Aurora - D05)	Significant Outage: Require outage to replace the motor on MOD 520 in D05 substation. The following motor operated disconnect switches will be operated: 519B @ D05 Substation 520 @ D05 Substation 517A @ D05 Substation 215 @ G01 Substation
ALTALINK	26-Jun-23 09:00	30-Jun-23 16:00	4.29 Days Continuous	820AL (315s Chin Chute - 820L tap), 820L (254s Coaldale - 820AL tap), 820BL (967s Redcoat - 820L tap), 820L (67s Stirling - 820BL tap), 820L (820AL tap - 820BL tap)	Install and commissioning new D60 and SEL311 settings update, SCADA updates, new telecom equipment installed and commissioned and new RAS relays at 254s installed and commissioned.
ATCO	26-Jun-23 09:30	28-Jun-23 12:00	2.1 Days Continuous	863S 902T, 863s 902T (863s Paintearth)	902T TRANSFORMER CLASS1 MAJOR TESTING Offload 902T to 901T.
EPCOR, ALTALINK	26-Jun-23 09:30	28-Jun-23 17:00	2.31 Days Continuous	1045L @ Jasper Terminal E805S and Sundance 310P and Keephills 320P, 1045L (EP 805s Jasper - 1045AL tap)	Jasper: 1045L Surge Arrestor LCR
ATCO	26-Jun-23 10:00	28-Jun-23 17:30	2.31 Days Continuous	888s 902 (888s Dover)	902 BKR Maintenance
ALTALINK	27-Jun-23 07:15	27-Jun-23 17:45	10.5 Hours Continuous	887L (48s Pocaterra - 978s BCH Britt Creek)	PLC C Alarm on 04LE card, requires replacement of card to correct.	AB-BC
SUNCOR	27-Jun-23 08:00	29-Jun-23 18:00	2.42 Days Continuous	29PL9-16, 29PL9-16 (29EDD-1 Millennium - 29EDD-94 Voyageur)	Line outage to Tie in CT CCT for new DFR
ALTALINK	27-Jun-23 09:30	27-Jun-23 15:30	6 Hours Daily	320p PS2 (320p Keephills), 320p 2652 (320p Keephills), 320p 2752 (320p Keephills)	1st trip & PRC5 maintenance & change cabinet heater
BCH	28-Jun-23 09:00	28-Jun-23 17:00	8 Hours Continuous	1L275 (799s Coleman - BCH Natal)	BFPN testing	AB-BC
ALTALINK	28-Jun-23 09:30	28-Jun-23 15:30	6 Hours Daily	320p PS2 (320p Keephills), 320p 2752 (320p Keephills), 320p 2652 (320p Keephills)	1st trip & PRC5 maintenance
ALTALINK	28-Jun-23 09:30	28-Jun-23 15:30	6 Hours Daily	650s 652 (650s Hansman Lake)	1st trip & PRC5 maintenance
BCH	28-Jun-23 10:00	28-Jun-23 15:00	5 Hours Continuous	2L294 (BCH A. A. Lambert - BCH Nelway)	inspection and doble of 2SSVT1	AB-BC
ATCO	28-Jun-23 10:00	29-Jun-23 16:00	30 Hours Continuous	794S 704, 7L54, 7L54 (794s Valleyview - 813s Little Smoky)	breaker maintenance
ATCO	28-Jun-23 13:00	30-Jun-23 17:30	2.19 Days Continuous	863S 901T, 863s 901T (863s Paintearth)	901T TRANSFORMER CLASS1 MAJOR TESTING Offload 901T to 902T.
ENMAX, ALTALINK	30-Jun-23 08:00	30-Jun-23 16:00	8 Hours Continuous	28.80L (42s Sarcee - SS-28)	Power factor test 28B138-28.80-CT
SUNCOR	30-Jun-23 08:00	30-Jun-23 20:00	12 Hours Continuous	29EDD-34 29PT-340 (29EDD-34)	29PT-340 Logic changes ABB 670 Relay
SUNCOR	30-Jun-23 08:00	02-Jul-23 18:00	2.42 Days Continuous	29PL9-17, 29PL9-17 (29EDD-1 Millennium - 29EDD-94 Voyageur)	Line outage to Tie in CT CCT for new DFR
ATCO	30-Jun-23 08:30	30-Jun-23 15:00	6.5 Hours Continuous	7L128 (802s Michichi Creek - 7LA128 tap)	Install Missing hardware due to backorders on 7L128D2 vacuum bottles.
ATCO	30-Jun-23 08:30	30-Jun-23 17:30	9 Hours Continuous	963S 901T, 9L29, 9L29 (946s Oakland - 963s Coyote Lake), 963s 901T (963s Coyote Lake)	Outage taken at same time as 2-71564 (7L128 already out of service) 901T at 963S Coyote leak repairs investigation Repair 9L29GS1 at 963s Coyote Lake
EPCOR, ALTALINK	30-Jun-23 17:00	22-Jul-23 17:00	22 Days Continuous	1059L (TX1 East Ind) @ Lambton E803S and East Industrial E52S and East Edmonton 38S, 1059AL (52s East Industrial - 1059L tap), 1059L (38s East Edmonton - 1059AL tap), 1059L (EP 803s Lambton - 1059AL tap)	1059L: Aerial- Steel Structure Refurbishment
BCH	02-Jul-23 11:00	02-Jul-23 16:00	5 Hours Continuous	5L71 (BCH Mica G.S. - BCH Nicola), 5L72 (BCH Mica G.S. - BCH Nicola)	MCA Black start testing	AB-BC
FMGW, SUNCOR	03-Jul-23 06:00	16-Jul-23 18:00	13.5 Days Continuous	29PP-45 @ 29EDD-34, 29EDD-34 29-952-143 (29EDD-34), 29EDD-34 29-952-133 (29EDD-34), 29EDD-34 29-952-113 (29EDD-34), 29EDD-34 29-952-123 (29EDD-34)	BP - 29EDD34;29PP-45 SYSTEM and 29PT-224 SSVT
ALTALINK	03-Jul-23 11:00	13-Jul-23 17:00	10.25 Days Continuous	310p T30 (310p Sundance), 234L (310p Sundance - 505L tap), 512L (310p Sundance - 521L tap), 310p 69kV Bus (310p Sundance)	69kV bus insulator replacements, 310s120 PT replacement, 310p3352 breaker replacement, 310p698, 310p694, 310p695, 310p692, 310p693, 310p691 switch replacements. RSLD 1******** to be implemented at the end of the outage.
ALTALINK	03-Jul-23 12:30	13-Jul-23 18:00	10.23 Days Continuous	256s T1(TX18555), 25kV W.Bus GOI, 256s T1 (256s Harmattan)	Replace switch 256s18. T1 oil reclaim. 256s20, 256s23, 256s10, 256s7 new switch signs required. 256s39 hot switch. 256s228X new counter
EPCOR	04-Jul-23 07:00	06-Jul-23 17:00	2.42 Days Continuous	SU2403 @ Summerside E657S, 657s SU2403 (657s Summerside)	Summerside: Summerside SU2403 Breaker Maintenance and CT Doble
EPCOR, ALTALINK	04-Jul-23 07:00	08-Jul-23 17:00	4.42 Days Continuous	Genesee S/S 430L Bay Isolation, 430L (330P Genesee - 510S Sunnybrook)	1.138kv 430L1 & L2 foundation installation 2. 138kv 12TC2L2 foundation installation
EPCOR, ALTALINK	04-Jul-23 07:00	14-Aug-23 17:00	41.42 Days Continuous	Cloverbar S/S 921L, Tx2 and Tx4 bays, 921L (71s Lamoureux - 987s Clover Bar), 987s C2404 (987s Clover Bar), 987s CDS35 (987s Cloverbar), 987s T4 (987s Clover Bar)	Initial stage of 240 kV ring re-configuration for new 1191L construction. New disconnects CDS41 and CDS44 to be energized post outage.
ALTALINK	04-Jul-23 09:00	06-Jul-23 18:00	2.38 Days Continuous	603L (138s Windy Flats - 243s Soderglen)	Maint. 603L between Structures #1 - 109
BCH	04-Jul-23 09:00	07-Jul-23 17:00	3.33 Days Continuous	T4 (BCH Natal)	Breaker Inspection and disconnect repair	AB-BC
ATCO	04-Jul-23 09:30	05-Jul-23 17:30	1.33 Days Continuous	755S 903, 755s 903 (755s Cordel)	BREAKER 903 SF6 GL315 COMPLETE TESTING
ATCO	04-Jul-23 10:00	05-Jul-23 16:00	30 Hours Continuous	732S 906, 732s 906 (732s Mitsue)	breaker maintenance
ATCO	04-Jul-23 10:00	05-Jul-23 16:00	30 Hours Continuous	7L69 (731s Elmworth - 815s Goodfare), 731S 702	breaker maintenance
ATCO	04-Jul-23 13:00	06-Jul-23 15:00	2.08 Days Continuous	7L85, 7L85 (801s Anderson - ATC 803s Bullpound)	7L85 Cross arm & insulator replacement between Anderson & Bullpound. 111 Structures
ALTALINK	05-Jul-23 08:00	05-Jul-23 17:00	9 Hours Daily	603L (138s Windy Flats - 243s Soderglen)	Aprisa radio maintenance.
ALTALINK	05-Jul-23 23:00	06-Jul-23 03:00	4 Hours Daily	62s 11 (62s Brazeau Plant)	maintenance
ALTALINK	06-Jul-23 03:00	06-Jul-23 07:00	4 Hours Daily	62s 12 (62s Brazeau Plant)	maintenance
ENMAX	06-Jul-23 08:00	06-Jul-23 16:00	8 Hours Continuous	162.81L (391s Balzac - SS-162)	Power factor test 162PT138-162.81
ATCO	06-Jul-23 10:00	07-Jul-23 16:00	30 Hours Continuous	7L73 (730s Rycroft - 829s Boucher Creek), 730S 703	breaker maintenance
ALTALINK	10-Jul-23 07:00	11-Jul-23 19:30	1.52 Days Continuous	251s 1148 (251s Whitla), 1148L (251s Whitla - 1018s Shamrock)	maintenance
EPCOR	10-Jul-23 07:00	14-Jul-23 17:00	4.42 Days Continuous	P2404 @ Petrolia E816S, 816s P2404 (816s Petrolia)	Petrolia: P2404 Bay CT LCR
EPCOR	10-Jul-23 07:00	16-Jul-23 17:00	6.42 Days Continuous	1058L @ Lambton E803S and Summerside E657S, 1058L (657s Summerside - EP 803s Lambton)	Lambton: 1058L CVT/CT/Arrestor Doble and L2403 Breaker Maintenance and CT Doble and Pole Lighting Upgrade Project (Pole #3 on July 15)
ENMAX	10-Jul-23 08:00	10-Jul-23 12:00	4 Hours Continuous	65B240-D131 (SS-65)	HV breaker SF6 Gas Sample - 65B240-D131
SUNCOR	10-Jul-23 08:00	19-Jul-23 18:00	9.42 Days Continuous	29EDD-94 29-952-9701 (29EDD-94 Voyageur), 29EDD-94 29-952-9706 (29EDD-94 Voyageur)	BP -29PP-97 Outage for CBR scope & Asset Tie-ins Perform tie-in and commissioning of CT circuits from 9707 & 9712 CTs to A87-B97 and 87B/50BF-B97 , 29PT-412 to 50BF/25SC-9707 & 9712 and A87-B97 and 87B/50BF-B97, 50BF/25SC-9707 & 9712 to breaker 9701 & 9706, circ mod on 9701 & 9706 & 9707 & 9712
ALTALINK	10-Jul-23 08:30	10-Jul-23 17:30	9 Hours Daily	413L (239s Castle River - 632s Russell), 632s 413 (632s Russell)	1st Trip followed by maintenance
ALTALINK	10-Jul-23 08:30	27-Jul-23 12:30	17.17 Days Continuous	310p 2752 (310p Sundance)	310p2752 breaker replacement.
ATCO	10-Jul-23 10:00	12-Jul-23 16:00	2.25 Days Continuous	811S 707, 7L68, 7L68 (730s Rycroft - 811s Clairmont Lake), 811s 707 (811s Clairmont Lake)	breaker maintenance
ENMAX	10-Jul-23 12:00	10-Jul-23 16:00	4 Hours Continuous	65B240-D132 (SS-65)	HV breaker SF6 Gas Sample - 65B240-D132
ATCO	10-Jul-23 13:00	13-Jul-23 15:00	3.08 Days Continuous	7L85, 7L85 (801s Anderson - ATC 803s Bullpound)	7L85 Cross arm & insulator replacement between Anderson & Bullpound. 111 Structures
ENMAX	11-Jul-23 08:00	11-Jul-23 12:00	4 Hours Continuous	65B240-D133 (SS-65)	HV breaker SF6 Gas Sample - 65B240-D133
SUNCOR	11-Jul-23 08:00	13-Jul-23 18:00	2.42 Days Continuous	29PL9-5, 29PL9-5 (29EDD-1 Millennium - 29EDD-34)	Line outage to Tie in CT CCT for new DFR
ENMAX	11-Jul-23 12:00	11-Jul-23 16:00	4 Hours Continuous	65B240-D134 (SS-65)	HV breaker SF6 Gas Sample - 65B240-D134
ALTALINK	11-Jul-23 12:00	11-Jul-23 16:30	4.5 Hours Daily	225s 225E (225s Magrath), 225L (225s Magrath - 225AL tap)	Installing new RAS 128 Relays and performing trip tests from all RAS 128 Relays.
ENMAX	12-Jul-23 08:00	12-Jul-23 12:00	4 Hours Continuous	65B240-D135 (SS-65)	HV breaker SF6 Gas Sample - 65B240-D135
ALTALINK	12-Jul-23 10:00	12-Jul-23 14:00	4 Hours Daily	250p 11 (250p Bighorn Plant)	maintenance
ALTALINK	13-Jul-23 10:00	13-Jul-23 14:00	4 Hours Daily	250p 22 (250p Bighorn Plant)	maintenance
ALTALINK	14-Jul-23 07:00	17-Jul-23 17:00	3.42 Days Continuous	786L (799s Coleman - BCH Natal), 799s 138kV Bus (799s Coleman)	Install micro piles for pile repair, move metering and 799s786W breaker handle from Panel 14 to make room for new panel 14 and breaker protections. Replace 786L stain glass at 799s A frame.
SUNCOR	14-Jul-23 08:00	16-Jul-23 18:00	2.42 Days Continuous	29PL9-6, 29PL9-6 (29EDD-1 Millennium - 29EDD-34)	Line outage to Tie in CT CCT for new DFR
EPCOR	17-Jul-23 07:00	19-Jul-23 17:00	2.42 Days Continuous	SU2402 @ Summerside E657S, 657s SU2402 (657s Summerside)	Summerside: SU2402 Breaker Maintenance and CT Doble
EPCOR	17-Jul-23 07:00	28-Jul-23 17:00	11.42 Days Continuous	TX2 @ Cloverbar E987S, 987s T2 (987s Clover Bar)	Cloverbar: TX2 DGA Install
ATCO	17-Jul-23 10:00	21-Jul-23 16:00	4.25 Days Continuous	845S 701, 845S 702, 7L45 (798s Bridge Creek - 813s Little Smoky)	breaker maintenance 701, 702, switch inspections 702B, 701B, 701A
ATCO	17-Jul-23 10:00	31-Jul-23 10:00	14 Days Continuous	7L45 (798s Bridge Creek - 813s Little Smoky)	813S Little Smoky Rebuild813S Little Smoky Rebuild BKR 703 and 704 P&C wiring, remove old panel 7G, set up new panel 7P4, prep work Relay programming and functionality Commission control, alarms and status
ALTALINK	17-Jul-23 12:00	20-Jul-23 18:00	3.25 Days Continuous	1082L (63s - 287s) GOI, 1082L (63s Red Deer - 287s Hazelwood)	Comp replacement str. 1-60 FRM
ATCO	17-Jul-23 13:00	19-Jul-23 16:00	2.13 Days Continuous	825S 906, 825s 906 (825s Whitefish Lake)	906 Maintenance and PRC 005 Testing
ATCO	17-Jul-23 13:00	20-Jul-23 15:00	3.08 Days Continuous	7L85, 7L85 (801s Anderson - ATC 803s Bullpound)	7L85 Cross arm & insulator replacement between Anderson & Bullpound. 111 Structures
ALTALINK	17-Jul-23 13:00	20-Jul-23 16:00	3.13 Days Continuous	310p T30 (310p Sundance)	310p T30 25kV Bushing replacement, 69kV Bushing replacement, 69kV LA install, leak repair, maintenance, doble.
ALTALINK	18-Jul-23 09:00	18-Jul-23 16:30	7.5 Hours Daily	275sT2(Tx18458) GOI, 275s T2 (275s Jenner)	inspect 275s47 and confirm it operates and adjust if need be
BCH	18-Jul-23 09:00	19-Jul-23 17:00	1.33 Days Continuous	T2 (BCH Natal), 60CB2 (BCH Natal)	breaker inspection	AB-BC
ALTALINK	18-Jul-23 09:30	18-Jul-23 15:30	6 Hours Daily	320p 2052 (320p Keephills), 320p 2152 (320p Keephills), 903L (17s Benalto - 320p Keephills)	1st trip & PRC5 maintenance
ALTALINK	18-Jul-23 09:30	18-Jul-23 15:30	6 Hours Daily	320p 2852 (320p Keephills)	1st trip & PRC5 maintenance
ATCO	18-Jul-23 09:30	20-Jul-23 08:30	1.96 Days Continuous	2075s ACF21 (2075s Newell)	Fire system testing in SVC2
ALTALINK	19-Jul-23 09:30	19-Jul-23 15:30	6 Hours Daily	320p 2152 (320p Keephills)	1st trip & PRC5 maintenance
ALTALINK	20-Jul-23 12:00	20-Jul-23 18:00	6 Hours Continuous	1109L (SS-25 - SS-65)	Summer Substation Washing
SUNCOR	22-Jul-23 08:00	31-Jul-23 18:00	9.42 Days Continuous	29PP-98 Outage at 29EDD94	BP -29PP-98 Outage for CBR scope & Asset Tie-ins Perform tie-in and commissioning of CT circuits from 9709 & 9710 CTs to A87-B98 and 87B/50BF-B98 , 29PT-413 to 50BF/25SC-9709 & 9710 and A87-B98 and 87B/50BF-B98, 50BF/25SC-9709 & 9710 to breaker 9703 & 9704, 9704 & 9703 & 9709 & 9710
BCH	23-Jul-23 09:00	09-Aug-23 17:00	17.33 Days Continuous	2L293 (BCH Nelway - BCH Selkirk)	replace timbers	AB-BC
ALTALINK	24-Jul-23 07:00	25-Jul-23 18:00	1.46 Days Continuous	691L (419s - 74s) GOI, 691L (74s Janet - 419s Chestermere)	691L FRM Component Replacement (2-4)
EPCOR	24-Jul-23 07:00	26-Jul-23 17:00	2.42 Days Continuous	SU2401 @ Summerside E657S, 657s SU2401 (657s Summerside)	Summerside: SU2401 Breaker Maintenance and CT Doble
ATCO	24-Jul-23 09:00	31-Jul-23 16:00	7.29 Days Continuous	7L228 (845s Big Mountain - 2091S), 7L228 (845s Big Mountain - 7L20 tap)	Pole Repairs from Test & Treat
ATCO	24-Jul-23 10:00	28-Jul-23 16:00	4.25 Days Continuous	845S 708, 7L46, 7L46 (813s Little Smoky - 845s Big Mountain)	breaker maintenance 708, 709, switch inspections 708A, 709A
ALTALINK	24-Jul-23 10:00	03-Aug-23 18:00	10.33 Days Continuous	64s 240kV Bus (64s East Crossfield), 901L (74s Janet - 901AL tap), 64s T2 (64s East Crossfield), 901AL (64s East Crossfield - 901L tap), 901L (63s Red Deer - 901AL tap), 64s 901 (64s East Crossfield)	Replace 64s29, 64s28 and CVT1 (64s32)
ATCO	24-Jul-23 10:00	04-Aug-23 10:00	11 Days Continuous	813S 706, 813S 712, 813S SVC, 813s SVC (813s Little Smoky), 813s RTU/SCADA (813s Little Smoky)	Protection cutover for 5&7 harmonic relays for SVC Wiring in 703T CT circuit
ATCO	24-Jul-23 10:00	14-Aug-23 17:00	21.29 Days Continuous	7L587, 7L587 (822s Wolf Lake - 826s Marguerite Lake)	822S Wolf lake P&C and SCADA Upgrade Work on Breaker 822S 701 Cut over cabling and protection to new panel Commission new protection including teleprotection DTT to 826S
ALTALINK	24-Jul-23 12:30	27-Jul-23 17:30	3.21 Days Continuous	63s 852 (63s Red Deer)	1st trip PRC 5 maintenance
ATCO	24-Jul-23 13:00	04-Aug-23 17:00	11.17 Days Continuous	939S 903T, 939S 903T Protection, 939s 903T (939s Livock)	903T Maintenance
BCH	25-Jul-23 09:00	26-Jul-23 17:00	1.33 Days Continuous	2L293 (BCH Nelway - BCH Selkirk)	inspections	AB-BC
ATCO	25-Jul-23 10:00	21-Aug-23 17:00	27.29 Days Continuous	7L16, 766S 144KV Bus, 7L16 (766s Nevis - 948s Heatburg), 766s 901T (766s Nevis), 766s 701T (766s Nevis)	766S Nevis Rebuild Project - P&C wiring and commissioning 7L16 and 701T protection upgrade, refurbish 701T tapchanger Replace 500D1/D2, and Bkr 502
ATCO, ALTALINK	25-Jul-23 13:00	27-Jul-23 13:00	2 Days Continuous	7L760D3 (7LA760 tap), 760L (760AL tap - 7LA760 tap)	Pole change for clearance mitigation 7L760 structures 515, 516, 538
ALTALINK	26-Jul-23 09:30	27-Jul-23 17:30	1.33 Days Continuous	320p 652 (320p Keephills)	1st trip & PRC5 maintenance, fix leaks
EPCOR	27-Jul-23 07:00	27-Jul-23 17:00	10 Hours Continuous	TX2 Zone @ Poundmaker, T2 (Poundmaker)	Poundmaker: TX2 Zone CVT Doble
ALTALINK	28-Jul-23 07:00	28-Jul-23 17:00	10 Hours Daily	170L (632s Russell - 799s Coleman)	Replace strain glass on 170L on 799s A frame
EPCOR	31-Jul-23 07:00	23-Aug-23 17:00	23.42 Days Continuous	1058L @ Lambton E803S and Summerside E657S, 1058L (657s Summerside - EP 803s Lambton)	1058L: Aerial- Structure Refurbishment Steel
EPCOR, ALTALINK	31-Jul-23 09:30	04-Aug-23 17:00	4.31 Days Continuous	930L @ Poundmaker and North Calder 37S, 930L (37s North Calder - Poundmaker)	930L: Aerial- Broken Insulator Replacement and Marker Cones Upgrade
ATCO	31-Jul-23 10:00	01-Aug-23 16:00	30 Hours Continuous	845S 710, 7L44, 7L44 (749s Flyingshot Lake - 845s Big Mountain)	breaker maintenance 710, switch inspections 709B, 710B
ATCO	01-Aug-23 10:00	01-Aug-23 16:00	6 Hours Continuous	790S 703, 7L07, 7L07 (790s Poplar Hill - 815s Goodfare), 790s 703 (790s Poplar Hill)	breaker partial maintenance
ATCO	02-Aug-23 10:00	02-Aug-23 16:00	6 Hours Continuous	733S 701, 7L80, 7L80 (733s Simonette - 857s Kakwa Ridge), 733s 701 (733s Simonette)	breaker partial maintenance
ATCO	02-Aug-23 10:00	04-Aug-23 16:00	2.25 Days Continuous	845S 703, 7L228 (845s Big Mountain - 2091S), 845s 703 (845s Big Mountain), 7L228 (845s Big Mountain - 7L20 tap)	breaker maintenance 703, switch inspections 703B, 704BB
ENMAX, ALTALINK	03-Aug-23 08:00	03-Aug-23 16:00	8 Hours Continuous	832L (SS-10 - SS-12)	HV breaker SF6 Gas Sample - 10B138-832L
SUNCOR	03-Aug-23 08:00	05-Aug-23 18:00	2.42 Days Continuous	29EDD-94 Voyageur	BP -Perform initial energization(including all the post energization checks) for the newly extended portion of Voyageur substation from 29PP-97 bus and 29PP-98 bus.
ATCO	07-Aug-23 12:00	11-Aug-23 16:00	4.17 Days Continuous	876S 9L15 Protection Relay, 9L15, 876S 906, 876S 904, 876S 240kV Breaker Relays, 9L15 (834s Wesley Creek - 876s Brintnell), 876s 904 (876s Brintnell), 876s 906 (876s Brintnell)	21B/ 9L15 RTXP Test Switch Replacement, PRC-005 Relay Testing 21A&B / 9L15 an 50BF/ Bkr 904&906, PRC-005 Trip Coil Testing Breaker 904 & 906
ATCO	08-Aug-23 09:00	14-Aug-23 16:00	6.29 Days Continuous	7L228 (845s Big Mountain - 2091S), 7L228 (845s Big Mountain - 7L20 tap)	Pole Repairs from Test & Treat
ATCO	08-Aug-23 10:00	09-Aug-23 16:00	30 Hours Continuous	845S 707, 845S 708, 7L33 (749s Flyingshot Lake - 7LA33 tap)	switch inspections 707B, 708B
ALTALINK	08-Aug-23 10:00	10-Aug-23 18:00	2.33 Days Continuous	64s T1 (64s East Crossfield)	Replace 25kV PT1 (64s24) & adjust switch 64s589
ATCO	08-Aug-23 16:00	09-Aug-23 16:00	24 Hours Continuous	7L85, 7L85 (803s ATC Bullpound - 7LA85 tap)	Replace 7L85 structure 367.1 from test and treat. Between Badlands and Bullpound.
ALTALINK	09-Aug-23 13:30	09-Aug-23 17:30	4 Hours Daily	77s 40 (77s Sagitawah)	1st trip & PRC5 maintenance on 77s40
ATCO	09-Aug-23 16:15	10-Aug-23 13:00	20.75 Hours Continuous	7L85, 7L85 (804s Wintering Hills - 7LA85 tap)	Replace 7L85 structure 484 from test and treat. Between Badlands Wintering Hills.
ALTALINK	10-Aug-23 08:30	10-Aug-23 16:30	8 Hours Daily	89s 1552 (89s Ellerslie)	1st trip & PRC5 maintenance, fix
EPCOR	14-Aug-23 07:00	16-Aug-23 17:00	2.42 Days Continuous	CD2406 @ Castledowns E557S, 557s CD2406 (557s Castle Downs)	Castledowns: CD2406 Tank Heater Repair (034597)
ALTALINK	14-Aug-23 07:30	17-Aug-23 16:30	3.38 Days Continuous	510s ACF14 (510s Sunnybrook)	Doble TX18882 Reactor, Breaker Dashpot Inspection and 6MD66 relay maintenance
ALTALINK	14-Aug-23 09:00	17-Aug-23 18:00	3.38 Days Continuous	64s 138kV Bus1 (64s East Crossfield), 64s T1 (64s East Crossfield), 64s T2 (64s East Crossfield), 64s 652 (64s East Crossfield)	Replace 138kV CVT2 (64s27)
ATCO	14-Aug-23 09:00	21-Aug-23 16:00	7.29 Days Continuous	7L03 (749s Flyingshot Lake - 7L09 tap)	Replacing red tag poles
ALTALINK	14-Aug-23 13:00	17-Aug-23 17:00	3.17 Days Continuous	87s T1 (87s Gaetz)	Maintain & test - PRC5
ALTALINK	15-Aug-23 07:00	18-Aug-23 18:00	3.46 Days Continuous	202L (61s Lodgepole - 62s Brazeau Plant Plant)	202L str. 108-117 Comp. Replacement
EPCOR	17-Aug-23 07:00	22-Sep-23 17:00	36.42 Days Continuous	Cloverbar S/S 240 kV ring open from CDS31 to CDS39, 987s CDS34 (987s Cloverbar)	Continued re-configuration of 240 kV ring for new 1191L bay construction will leave the ring open from newly energized CDS41 and CDS44 disconnects.
EPCOR	21-Aug-23 07:00	21-Aug-23 17:00	10 Hours Continuous	657s T1 (657s Summerside)	Summerside: TX1 Tap Changer Maintenance
ALTALINK	21-Aug-23 07:00	29-Aug-23 17:00	8.42 Days Continuous	983L/983AL (244s - I_1019s - 251s) - GOI, 983AL (1019s Woolchester - 983L tap), 983L (244s Bowmanton - 983L tap), 983L (251s Whitla - 983L tap)	Creating in/out for the new 264s Elkwater Substation between Structures #133 & 134. Also, installing laminate pole on T-tap to I-1019s @ Structure #117
EPCOR, ALTALINK	21-Aug-23 09:30	01-Sep-23 17:00	11.31 Days Continuous	920LW Zone @ Castledowns E557S and North Calder 37S, 920L (37s North Calder - 557s Castle Downs)	Castledowns: CD2403/CD2401 Breaker Maintenance and 920LW CVT/Arrestor/CT Doble and CDDS2/CDDS3/CDDS12 Disconnect Maintenance
ATCO	21-Aug-23 10:00	28-Aug-23 17:00	7.29 Days Continuous	9L16, 9L16 (755s Cordel - 972s Tinchebray)	Upgrade 21A/B-9L16 protection relay wiring/programming and commission LTO/DTT
ALTALINK	21-Aug-23 13:00	23-Aug-23 16:00	2.13 Days Continuous	103s T1(Tx 18776) GOI, 103s T1 (103s Goose Lake)	Doble, maintenance, connector, steam clean. Requested By: MAPS South
ATCO	22-Aug-23 08:00	23-Aug-23 17:00	1.38 Days Continuous	7L24 (700s Bonnyville - 7LA24 tap)	Line to ground clearance mitigation pole replace 7L24 structure 54 & 64
ALTALINK	22-Aug-23 08:30	24-Aug-23 13:30	2.21 Days Continuous	171s T1 (171s Redwater)	PRC5 maintenance, fix tap changer, replace hydran battery, test transformer
ALTALINK	22-Aug-23 09:00	22-Aug-23 16:00	7 Hours Daily	723s 252 (723s Christina Lake), 723s T2 (723s Christina Lake)	723s252 1st trip & PRC5 maintenance
BCH	22-Aug-23 09:00	02-Sep-23 17:00	11.33 Days Continuous	5L92 (BCH Cranbrook - BCH Selkirk)	breaker repair	AB-BC
ATCO, IMPERIALOIL	23-Aug-23 08:00	30-Sep-23 18:00	38.42 Days Continuous	7L105 (837s Mahihkan - 909s Mahno), 7L161 (909s Mahno - 942s Nabiye), 909s 52A3 (909s MAHNO), 909s TNS-A1 (909s Mahno), 909s TNS-A2 (909s Mahno)	maintenance
ALTALINK	23-Aug-23 09:30	23-Aug-23 15:30	6 Hours Daily	72s 752 (72s Leismer)	1st trip & PRC5 maintenance
ATCO	23-Aug-23 09:30	24-Sep-23 16:00	32.27 Days Continuous	848S 29PL9-1 Protection Relay, 848S 29PL9-1 SUNCOR ISLANDING RAS (IRAS), 848S 903, 848S 906, 848s 903 (848s Ruth Lake), 848s 906 (848s Ruth Lake)	Suncor Capacity Increase project. Suncor is reconductoring 29PL9-1, ATCO is completing a line protection upgrade in coordination with the outage
ALTALINK	23-Aug-23 23:00	24-Aug-23 03:00	4 Hours Daily	62s 11 (62s Brazeau Plant)	maintenance
ALTALINK	24-Aug-23 03:00	24-Aug-23 07:00	4 Hours Daily	62s 12 (62s Brazeau Plant)	maintenance
EPCOR, ALTALINK	27-Aug-23 07:00	10-Sep-23 17:00	14.42 Days Continuous	Genesee S/S 430L Bay Isolation, 430L (330P Genesee - 510S Sunnybrook)	1.String BB2L , BB2L1 to BB2L2 & 12TC2L , 12TC2L1 to 12TC2L3 2. String BB2L , BB2L1 to BB2L2 & 12TC2L , 12TC2L1 to 12TC2L3
ATCO, IMPERIALOIL	28-Aug-23 09:00	28-Aug-23 13:00	4 Hours Continuous	837S 702, 837S 7L105 Protection Relay, 7L105, 837s 702 (837s Mahihkan), 7L105 (837s Mahihkan - 909s Mahno)	RTXP switch replacements for 7L105
ATCO	28-Aug-23 12:00	30-Aug-23 16:00	2.17 Days Continuous	876S 9L56 Protection Relay, 9L56, 876S 904, 876S 902, 876S 240kV Breaker Relays, 9L56 (720s Wabasca - 876s Brintnell), 876s 902 (876s Brintnell), 876s 904 (876s Brintnell)	21A&B/ 9L56, 50BF/902 RTXP Test Switch Replacement, PRC-005 Relay Testing 21A&B / 9L56 an 50BF/ Bkr 902, PRC-005 Trip Coil Testing Breaker 902
ALTALINK	28-Aug-23 12:00	31-Aug-23 18:00	3.25 Days Continuous	58s T2 (58s Edson)	58sT2 25kV bushings replacement and leakage reactance test, leaks and LA base insulators
ALTALINK	28-Aug-23 12:30	31-Aug-23 17:30	3.21 Days Continuous	310p 952 (310p Sundance)	Maintenance on 310p952 including 1st trips
ATCO	28-Aug-23 14:00	31-Aug-23 13:00	2.96 Days Continuous	7L171, 7L171 (802s Michichi Creek - 804s Wintering Hills)	Cross arm and insulator replacement on 7L171, 49 structures.
SUNCOR	01-Sep-23 08:00	01-Sep-23 17:00	9 Hours Continuous	635PT-1001, 635EDD-1000 635PT-1001 (635EDD-1000)	Planned Repair on Transformer 2ndary Side Breaker Mech Heaters
EPCOR	05-Sep-23 07:00	28-Sep-23 17:00	23.42 Days Continuous	240BA3 @ Argyll Transfer Station E629S and Bellamy E814S, 240BA3 (629s Argyll Transfer Station - 814s Bellamy)	240BA3: UGT Degassing Project
SUNCOR	05-Sep-23 08:00	19-Sep-23 18:00	14.42 Days Continuous	29EDD-1, 29EDD-1 29EDD1s752 (29EDD-1 Millennium)	N260B1 + Relays, 29CVT-11, 29PS-72/76. 29EDD-1S1/1S7/1S13/1S452/1S152 + Relays, 952-101/104 + Controller + Relays
ATCO	05-Sep-23 09:00	07-Sep-23 16:00	2.29 Days Continuous	7L228 (845s Big Mountain - 2091S), 7L228 (845s Big Mountain - 7L20 tap)	Pole Repairs from Test & Treat
ATCO	05-Sep-23 09:00	07-Sep-23 16:00	2.29 Days Continuous	7L03 (749s Flyingshot Lake - 7L09 tap)	Changing Rotten Poles
ATCO	05-Sep-23 12:00	10-Sep-23 17:30	5.23 Days Continuous	7L45 (798s Bridge Creek - 813s Little Smoky)	7L45D2 switch replacement 7L45 between 845S Big Mountain and 798S Bridge Creek to remain in service
ALTALINK	06-Sep-23 07:00	06-Sep-23 18:00	11 Hours Daily	745L (602s Cold Creek - 745AL tap)	Replace insulators on structure 574. Replace bayonet bolts & hardware tighten structures 628 & 630.
ALTALINK	06-Sep-23 08:00	14-Sep-23 15:00	8.29 Days Continuous	253s Station GOI, 753L (65s High River - 253s Blackie), 851L (253s Blackie - 525s Carseland), 876L (179s Gleichen - 253s Blackie), 253s 753W (253s Blackie), 253s 851W (253s Blackie), 253s 876 (253s Blackie), 253s C1 (253s Blackie)	Replace multiple 138kV switches, 253s1, 253s2, 253s5, 253s6,253s9, 253s179 and 253s181. Replacement of wooden support beams to steel for switches. Replace 138kV strain insulators (10 sets throughout station)
ATCO	06-Sep-23 09:30	08-Sep-23 16:00	2.27 Days Continuous	969S 301, 969S 701T, 969S 501, 969s 701T (969s Lindbergh)	701T Maintenance, and leak repairs 301 Close latch repairs
EPCOR	11-Sep-23 07:00	11-Sep-23 17:00	10 Hours Continuous	VDS20 @ Victoria E511S, EP 511s VDS20 (EP 511s Victoria)	Victoria: VDS20 Disconnect Repair
ALTALINK	11-Sep-23 07:00	21-Sep-23 17:00	10.42 Days Continuous	1325L WATL (510s-511s) - GOI, 1325L (510s Sunnybrook - AML 511s Crossings)	Annual Link Outage, Station Misc work, Valve Hall Inspections, DC Bushing Doble, VCS Load bank testing.
ATCO	11-Sep-23 09:00	15-Sep-23 16:00	4.29 Days Continuous	7L62 (789s Keg River - 797s Kemp River)	Line to Ground Mitigation
ATCO	11-Sep-23 09:00	12-Nov-23 16:00	62.33 Days Continuous	7L63 (780s Lubicon - 812s Norcen)	Changing Rotten X Arms, poles and Line Mitigation
ALTALINK	11-Sep-23 12:00	14-Sep-23 18:00	3.25 Days Continuous	89s T2 (89s Ellerslie)	Bushing monitor replacement on all 3 phases and replace DGA monitor. Replacing PD monitor on T2-2 phase only.
ALTALINK, Lethbridge	11-Sep-23 13:00	14-Sep-23 17:00	3.17 Days Continuous	618s 824 (618s Riverbend), 824L (593s Lakeview - 618s Riverbend)	Change out CTs on 618s824
ALTALINK	12-Sep-23 07:30	13-Sep-23 08:00	24.5 Hours Continuous	163s T2(Tx18482) Advice for Customer, 163s T2 (163s Amoco Empress)	to replace bolted connections to crimp connections on the cables feeding T2.
ALTALINK	13-Sep-23 08:05	13-Sep-23 16:30	8.42 Hours Continuous	163s T1(Tx18483) Advice for Customer, 163s T1 (163s Amoco Empress)	to replace bolted connections to crimp connections on the cables feeding T1.
ATCO	16-Sep-23 09:00	17-Sep-23 16:00	31 Hours Continuous	7L62 (789s Keg River - 797s Kemp River)	Line to Ground Mitigation
ATCO	18-Sep-23 10:00	18-Sep-23 17:00	7 Hours Continuous	9L20, 9L912, 9L20 (755s Cordel - 766s Nevis), 9L912 (63s Red Deer - 766s Nevis)	766S Nevis Rebuild Project - Hot Line crew connect 9L20/9L912 bypass, cut in open Jumper J1 and J2
ATCO	18-Sep-23 10:00	09-Oct-23 17:00	21.29 Days Continuous	822S 703, 822s 703 (822s Wolf Lake)	822S Wolf lake P&C and SCADA Upgrade Work on Breaker 822S 703 Cut over cabling and protection to new panel. Commission new protection including teleprotection DTT. 7L86/7L574 bypass will be in service
ALTALINK	18-Sep-23 11:00	21-Sep-23 17:00	3.25 Days Continuous	618s 725 (618s Riverbend), 725L (111s Coalbanks - 725AL tap), 725L (674s Bowron - 725AL tap), 725AL (618s Riverbend - 725L tap)	Change out CTs on 618s725 & single line phase CVT on 618s14
ALTALINK	18-Sep-23 12:00	21-Sep-23 17:00	3.21 Days Continuous	28sT1(Tx18701) GOI, 28s T1 (28s West Brooks)	replace leaking HOXO bushing
ALTALINK	18-Sep-23 12:00	21-Sep-23 18:00	3.25 Days Continuous	89s T1 (89s Ellerslie)	Bushing monitor replacement on all 3 phases and replace DGA monitor. Replacing PD monitor on T1-2 phase only.
ALTALINK	18-Sep-23 13:30	21-Sep-23 17:30	3.17 Days Continuous	310p 2652 (310p Sundance)	1st trip & then full maintenance: replace grading caps, fix close dashpot leaks
EPCOR	19-Sep-23 07:00	29-Sep-23 17:00	10.42 Days Continuous	Genesee S/S 12TC2 Bay Outage, 330P 12TC2 (330p Genesee)	Screw piles installation on west end of existing 500kv bus 2
ATCO	19-Sep-23 10:00	24-Sep-23 17:00	5.29 Days Continuous	9L93, 9L93 (615s Halkirk - 972s Tinchebray)	Connect new 9LA93 T-tap. Cut in, reroute, restring, and splice OPGW from Str#60 to 615S Halkirk. Complete cutover and commission Protection/SCADA/Telecom at new 973S Lanes Lake, 972S, 615S Halkirk
ATCO	19-Sep-23 10:00	04-Dec-23 17:00	76.33 Days Continuous	766S 144KV Bus, 766S 240KV Bus, 766s 701 (766s Nevis), 766s 901T (766s Nevis)	766S Nevis Rebuild Project - Replace and commission 9L912D1, 9L20D2, 901, 902, 901CT, 902CT, 901A, 902A, 900PT1, connect new 903A and 704A
ALTALINK	22-Sep-23 08:30	24-Sep-23 18:00	2.4 Days Continuous	38s T4 (38s East Edmonton), 38s 240kV Bus 2 (38s East Edmonton)	38s T4 PRC5 testing, maintenance, & fix leaks. 38s57 hotspot repair.
ALTALINK	23-Sep-23 08:30	24-Sep-23 16:30	1.33 Days Continuous	237s T2 (237s Foothills)	PRC5 Doble Maintenance and IDD
EPCOR	25-Sep-23 07:00	06-Oct-23 17:00	11.42 Days Continuous	Cloverbar S/S Tx4 bay and 1191L bay, 987s CDS35 (987s Cloverbar)	Continued re-configuration 240 kV ring for new 1191L bay
ALTALINK	25-Sep-23 08:30	29-Sep-23 16:30	4.33 Days Continuous	510s ACF22 (510s Sunnybrook), 510s ACF21 (510s Sunnybrook), 510s 1952 (510s Sunnybrook), 510s 2052 (510s Sunnybrook)	Rebalance ACF21 A phase, replace a leaky capacitor in ACF 22 A and C phase.
ATCO	25-Sep-23 09:30	29-Sep-23 17:30	4.33 Days Continuous	2029S ACF21, 2029S ACF22, 2029S ACF23, 2029s ACF21 (2029s Heathfield), 2029s ACF22 (2029s Heathfield), 2029s ACF23 (2029s Heathfield)	PRC-005 testing, filter bank inspections
ATCO, ALTALINK	25-Sep-23 11:00	06-Nov-23 13:00	42.13 Days Continuous	9L55, 885S 902T, 885S 704, 885S 500PT2, 885S 500SST2X, 885S 501, 885S 700PT2, 9L55 (AML 852s Round Hill - 885s McMillan), 885s 902T (885s McMillan)	885S McMillan sub Protection Upgrade: Complete protection cut over and Commissioning of new protection on 902T, 704/7L02 Line protection, 25kV Reactor protection. On Monday October 23, 2023 will extend GOI to new isolation points: 501A,502TD1,502TD1,703B,7L02D2,906B,902A,Switch @ Round Hill (Alta Link). The following will be OOS: 900BS2, 903,902,9L55,902T,704/7L02,144kV Bus. Complete cut over and Commissioning of new protection to 240kV bus, 903,902,9L55 line protection.
ALTALINK, ATCO	26-Sep-23 08:30	26-Sep-23 12:30	4 Hours Daily	526s 152 (526s Buffalo Creek), 7L129 (526s Buffalo Creek - 7LA129 tap)	1st trip and PRC5 maintenance
ALTALINK, ATCO	26-Sep-23 12:30	26-Sep-23 17:30	5 Hours Daily	526s 252 (526s Buffalo Creek), 7L50 (526s Buffalo Creek - 491L tap), AltaLink Distribution Breaker	1st trip and PRC5 maintenance
BHE Canada	02-Oct-23 08:00	07-Oct-23 18:00	5.42 Days Continuous	MATL (120s Picture Butte - Montana)	align with 1201L outage	AB-MATL
ALTALINK	02-Oct-23 09:00	07-Oct-23 16:00	5.29 Days Continuous	520s T1 (affect 1114L) - GOI, 520s T1 (520s Bennett), 1114L (102s Langdon - 520s Bennett), 520s 552 (520s Bennett)	T1 Bushing monitor replacement on all 3 phases + spare and DGA monitor (replacing PD monitor on T1-2 phase only). 520s1352 breaker maintenance, 102s2689 maintenance, 520s1201 maintenance
ALTALINK	02-Oct-23 09:00	07-Oct-23 18:00	5.38 Days Continuous	1201L/5L94 (520s - B2s) - GOI, 1201L (520s Bennett - BCH Cranbrook)	maintenance tasks str range 31-485 (Oct 2 - 7)	AB-BC
ALTALINK	02-Oct-23 13:30	05-Oct-23 17:30	3.17 Days Continuous	19s 49 (19s Wabamun), 19s T10 (19s Wabamun)	1st trip & PRC5 maintenance & major overhaul maintenance
ALTALINK	04-Oct-23 07:00	11-Oct-23 18:00	7.46 Days Continuous	953L (574s Nilrem - 755s Cordel)	Replace dampers on 953L structures 284-347
EPCOR	09-Oct-23 07:00	27-Oct-23 17:00	18.42 Days Continuous	Cloverbar S/S Tx2 bay and 1191L bay, 987s CDS32 (987s Cloverbar)	Continued re-configuration 240 kV ring for new 1191L bay. 1191L to be energize post outage with new isolation point of CDS45 to remain until 1191L is ready to energize.
ATCO, ALTALINK	09-Oct-23 09:00	12-Oct-23 16:30	3.31 Days Continuous	7L50 (526s Buffalo Creek - 491L tap), 7L50 (757s Battle River - 491L tap)	7L50 Pole and arm replacement
EPCOR, ALTALINK	10-Oct-23 07:00	14-Oct-23 17:00	4.42 Days Continuous	1059L @ Lambton and East Industrial E52S and East Edmonton 38S, 1059L (38s East Edmonton - 1059AL tap), EP 803s L2401 (EP 803s Lambton), EP 803s L2404 (EP 803s Lambton)	Lambton: 1059L CVT LCR
EPCOR	10-Oct-23 07:00	21-Oct-23 17:00	11.42 Days Continuous	240CV5 @ Castledowns E557S and Victoria E511S, CV5 (EP 511s Victoria - 557s Castle Downs)	CV5: UGT CV5 Annual Manhole Inspections
ALTALINK	10-Oct-23 08:00	19-Oct-23 17:00	9.38 Days Continuous	765L (151s Strathmore - 419s Chestermere)	Perform maintenance work on structures 56, 62, 63, 64, 65, 79-89, 136, 143, 151, 153, 157, 160-162, 173, 174, 183, 195-197, 202, 205, 213, 220, 222-226, 230, 237, 238, 255-265, 289-301, 304 & 305.
ALTALINK	11-Oct-23 10:00	11-Oct-23 14:00	4 Hours Daily	250p 11 (250p Bighorn Plant)	maintenance
ALTALINK	12-Oct-23 03:00	12-Oct-23 07:00	4 Hours Daily	62s 12 (62s Brazeau Plant)	maintenance
ALTALINK	12-Oct-23 10:00	12-Oct-23 14:00	4 Hours Daily	250p 22 (250p Bighorn Plant)	maintenance
ATCO, ALTALINK	16-Oct-23 09:00	19-Oct-23 16:30	3.31 Days Continuous	7L50 (526s Buffalo Creek - 491L tap), 7L50 (757s Battle River - 491L tap)	7L50 Pole and arm replacement
ALTALINK	18-Oct-23 07:00	25-Oct-23 18:00	7.46 Days Continuous	1047L (574s Nilrem - 650s Hansman Lake)	Replace dampers on 1047L structures 1-64
ALTALINK, ENMAX	23-Oct-23 09:15	26-Oct-23 16:45	3.31 Days Continuous	937L (5s - 102s) Advice, 937L (5s East Calgary - 102s Langdon)	SCADA Upgrade
ALTALINK	23-Oct-23 12:00	26-Oct-23 18:00	3.25 Days Continuous	320p T1 (320p Keephills)	Transformer maintenance. fix leaks, fan, & burned wires. Test transformer. 767L to be switched in to facilitate this outage.
ATCO, ALTALINK	30-Oct-23 09:00	02-Nov-23 16:30	3.31 Days Continuous	7L50 (526s Buffalo Creek - 491L tap), 7L50 (757s Battle River - 491L tap)	7L50 Pole and arm replacement
ALTALINK	30-Oct-23 09:30	02-Nov-23 16:45	3.3 Days Continuous	916L (5s - 42s) Advice, 916L (5s East Calgary - 42s Sarcee)	SCADA Upgrade
ALTALINK	30-Oct-23 10:00	09-Nov-23 18:00	10.38 Days Continuous	1034L (244s Bowmanton - 324s Cassils)	Comp. replacement (Str. 186-380)
ATCO	30-Oct-23 11:00	11-Dec-23 14:00	42.17 Days Continuous	863S 902T, 863S 500MT1, 863S 500PT3, 863S 505, 863S 506, 863s 902T (863s Paintearth)	863S Paintearth Protection Upgrade Demo wiring from 505, 506 breakers, and 500PT3, run new wiring, terminate to 505, 506, and 500PT3, demo old 5L470 & 5L469 line protection panel, install new 5L470 & 5L469 line protection panel, wire and commission breakers, 500PT3, and line protection. Demo old wiring, and old Transformer protection panel, install and terminate new wiring, and new Transformer protection panel. Commission new wiring/Transformer protection, and new Transformer protection panel. Once GOI is released 902TD will need to be commissioned.
ALTALINK, ENMAX	06-Nov-23 09:15	08-Nov-23 16:45	2.31 Days Continuous	936L (5s - 102s) Advice, 936L (5s East Calgary - 102s Langdon)	SCADA Upgrade
ATCO	06-Nov-23 15:00	20-Nov-23 13:00	13.92 Days Continuous	9L89, 885S 900 BUS 1, 885S 900PT1, 885S 900PT3, 885S 901, 885S 902, 9L89 (885s McMillan - 2011s Dawes), 885s 260kV Bus 900BS1 (885s McMillan)	885S McMillan sub Protection Upgrade: Complete protection cut over and Commissioning of new protection on 901,902,900PT1,9L89PT,9L89 Line Protection,900PT3.
ALTALINK	13-Nov-23 09:30	17-Nov-23 12:30	4.13 Days Continuous	5s T1(TX18903) Advice, 5s T1 (5s East Calgary)	SCADA Upgrade
ATCO, ALTALINK	13-Nov-23 10:00	24-Nov-23 18:00	11.33 Days Continuous	1035L (244s Bowmanton - 2075s Newell)	Comp. replacement (Str. 100 - 242)
ALTALINK	20-Nov-23 09:30	24-Nov-23 12:30	4.13 Days Continuous	5s T2(TX18835) Advice, 5s T2 (5s East Calgary)	SCADA Upgrade
ALTALINK	22-Nov-23 10:00	22-Nov-23 14:00	4 Hours Daily	250p 11 (250p Bighorn Plant)	maintenance
ALTALINK	23-Nov-23 10:00	23-Nov-23 14:00	4 Hours Daily	250p 22 (250p Bighorn Plant)	maintenance
ALTALINK	27-Nov-23 10:00	01-Dec-23 18:00	4.33 Days Continuous	1034L (244s Bowmanton - 324s Cassils)	Comp. replacement (Str. 186-380)
ALTALINK	29-Nov-23 23:00	30-Nov-23 03:00	4 Hours Daily	62s 11 (62s Brazeau Plant)	maintenance
ALTALINK	30-Nov-23 03:00	30-Nov-23 07:00	4 Hours Daily	62s 12 (62s Brazeau Plant)	maintenance
ALTALINK	04-Dec-23 08:00	08-Dec-23 17:00	4.38 Days Continuous	658L (562s - I_662s - 649s) - GOI, 658L (562s Cypress - 658AL tap), 658L (649s Chappice Lake - 658AL tap)	Component replacement 658L (str. 103-332)
ATCO	04-Dec-23 10:00	04-Dec-23 17:00	7 Hours Continuous	9L20, 9L912, 9L20 (755s Cordel - 766s Nevis), 9L912 (63s Red Deer - 766s Nevis)	766S Nevis Rebuild Project - Hot Line crew disconnect 9L20/9L912 bypass, close open Jumper J1 and J2, Energize 240kV bus including new 903T and 144kV bus
ATCO, ALTALINK	04-Dec-23 10:00	08-Dec-23 18:00	4.33 Days Continuous	1035L (244s Bowmanton - 2075s Newell)	Comp. replacement (Str. 100 - 242)
ALTALINK	11-Dec-23 12:00	14-Dec-23 17:00	3.21 Days Continuous	901L (63s - 64s - 74s) GOI, 901AL (64s East Crossfield - 901L tap), 901L (63s Red Deer - 901AL tap), 901L (74s Janet - 901AL tap)	FRM Str 3-370
ATCO	15-Jan-24 14:30	26-Feb-24 14:00	41.98 Days Continuous	863S 504, 863S 901T, 863S Station Service, 863S 500PT2X, 863S 500PT2Y, 863s 901T (863s Paintearth)	863S Paintearth Protection Upgrade
ATCO	12-Feb-24 11:00	20-May-24 14:00	98.08 Days Continuous	813S 901, 813s 901 (813s Little Smoky)	Take 901 OOS to open bus up and add a new 902PT, and 902 breaker bay for the new 9L201 line to MPC Gas. (February 12, 2024 - May 6, 2024) Will need to extend 901 GOI to take 903PT, 904, and 9L05 OOS to cut over 904 trips to new protection. (May 6, 2024 - May 20, 2024)
ATCO	26-Feb-24 14:30	11-Mar-24 14:00	13.94 Days Continuous	863S 902, 9L948, 9L948 (650s Hansman Lake - 863s Paintearth)	863S Paintearth Protection Upgrade Demo old wiring, and old Line protection panel, install and terminate new wiring, and new Line protection panel. Commission new wiring/Line protection, and new Line protection panel. Once GOI is released 902A will need to be commissioned.
ATCO	11-Mar-24 14:30	25-Mar-24 14:00	13.98 Days Continuous	863S 901, 9L27, 9L27 (755s Cordel - 863s Paintearth)	863S Paintearth Protection Upgrade Demo old wiring, and old Line protection panel, install and terminate new wiring, and new Line protection panel. Commission new wiring/Line protection, and new Line protection panel. Once GOI is released 901A will need to be commissioned.
ATCO	26-Apr-24 10:00	29-Apr-24 17:00	3.29 Days Continuous	9L80, 9L80 (755s Cordel - 757s Battle River)	Complete termination and commissioning of 9L80 LTO and 912T TO - A/B send to 755S Cordel
ATCO	06-May-24 09:00	31-May-24 17:30	25.35 Days Continuous	2029S BUILDING VALVE HALL, 2029s 1205 (2029s Heathfield), 2029s 1206 (2029s Heathfield)	Annual EATL outage at 2075s & 2029s. 2029s & 2075s AC & DC O&M. USE 2-70212 FOR 13L50 GOI USE 2-70213 FOR 2029s GOI USE 2-70214 FOR 2075s GOI
ATCO	06-May-24 09:00	31-May-24 17:30	25.35 Days Continuous	2075S BUILDING VALVE HALL, 2075s 916 (2075s Newell), 2075s 917 (2075s Newell)	Annual EATL outage at 2075s & 2029s. 2029s & 2075s AC & DC O&M. USE 2-70212 FOR 13L50 GOI USE 2-70213 FOR 2029s GOI USE 2-70214 FOR 2075s GOI
ATCO	06-May-24 09:00	31-May-24 17:30	25.35 Days Continuous	13L50 (DC LINK), 13L50 (2029s Heathfield - 2075s Newell)	Annual EATL outage at 2075s & 2029s. 2029s & 2075s AC & DC O&M. USE 2-70212 FOR 13L50 GOI USE 2-70213 FOR 2029s GOI USE 2-70214 FOR 2075s GOI
ATCO	03-Jun-24 08:00	14-Jun-24 17:30	11.4 Days Continuous	12L41 (510s Sunnybrook - 939s Livock), 12L44 (939s Livock - 951s Thickwood Hills)	APL O&M outage Use 2-70262 for 12L44 GOI Use 2-70263 for 939s-APL GOI Use 2-70264 for 951s-APL GOI APL O&M outage Use 2-70262 for 12L44 GOI Use 2-70263 for 939s-APL GOI Use 2-70264 for 951s-APL GOI
ATCO	03-Jun-24 10:00	28-Jun-24 10:00	25 Days Continuous	9L16, 9L16 (755s Cordel - 972s Tinchebray)	Upgrade 9L16 21A and 21B relays at both 755S Cordel and 972S Tinchebray. Connect new 9LA16 to new 620S Goldeye substation
ATCO	03-Jul-24 09:00	08-Sep-24 11:00	67.08 Days Continuous	848S 601, 848S 602, 848S 607, 848S 608, 848S 900BS1, 848S 901T, 848s 240kV Bus 900BS1 (848s Ruth Lake), 848s 901T (848s Ruth Lake)	848S Ruth Lake Substation Rebuild: Upgrading protection to IEC 61850, Demo 601PT,601B,601,601A,6L14D1,608A,608,608B,6LML1D1,600PT1, Replace breaker 401. Cut over to new protection: 602,607,607PT,601TD,901T,400PT1,400D1,901TD,903A,908A,913A. Install oil containment for 901T. Pull all new outdoor cable, modify cable tray, install new cable tray.
ENMAXEC	15-Jul-24 08:00	19-Jul-24 18:00	4.42 Days Continuous	383s T1 (383s Kettles Hill Windfarm), 383s T2 (383s Kettles Hill Windfarm)	substation maintenance
ATCO	16-Aug-24 10:00	16-Aug-24 17:00	7 Hours Continuous	801S 902, 801s 902 (801s Anderson)	Final connection of Bkr 902/52a single pole status inputs to DFR, Commission
ATCO	17-Aug-24 10:00	17-Aug-24 17:00	7 Hours Continuous	801S 903, 801s 903 (801s Anderson)	Final connection of Bkr 903 52a single pole status inputs to DFR, Commission
ATCO	18-Aug-24 10:00	18-Aug-24 17:00	7 Hours Continuous	801S 904, 801s 904 (801s Anderson)	Final connection of Bkr 904 52a single pole status inputs to DFR, Commission
ATCO	27-Aug-24 10:00	27-Aug-24 17:00	7 Hours Continuous	801S 905, 801s 905 (801s Anderson)	Final connection of Bkr 905 52a single pole status inputs to DFR, Commission
ATCO	28-Aug-24 10:00	28-Aug-24 17:00	7 Hours Continuous	801S 906, 801s 906 (801s Anderson)	Final connection of Bkr 906 52a single pole status inputs to DFR, Commission
ATCO	29-Aug-24 10:00	29-Aug-24 17:00	7 Hours Continuous	801S 907, 801s 907 (801s Anderson)	Final connection of Bkr 907 52a single pole status inputs to DFR, Commission
ATCO	30-Aug-24 10:00	30-Aug-24 17:00	7 Hours Continuous	801S 908, 801s 908 (801s Anderson)	Final connection of Bkr 908 52a single pole status inputs to DFR, Commission
ATCO	31-Aug-24 10:00	31-Aug-24 17:00	7 Hours Continuous	801S 909, 801s 909 (801s Anderson)	Final connection of Bkr 909 52a single pole status inputs to DFR, Commission
ATCO	01-Sep-24 10:00	01-Sep-24 17:00	7 Hours Continuous	801S 910, 801s 910 (801s Anderson)	Final connection of Bkr 910 52a single pole status inputs to DFR, Commission
ATCO	10-Sep-24 09:00	02-Dec-24 11:00	83.13 Days Continuous	848S 603, 848S 604, 848S 605T, 848S 606, 848S 848-501, 848S 848-504, 848S 848S 500BS2 25kv Protection System, 848S 900BS2, 848S 902T, 848s 240kV Bus 900BS2 (848s Ruth Lake), 848s 902T (848s Ruth Lake)	848S Ruth Lake Substation Rebuild: Upgrading protection to IEC 61850, Replace breakers 603 & 604. Cut over to new protection: 500D4,501,500D15,504,500PT2,500D10,504VR,605T,605TD,603PT,603,603CT,604,604CT,606,606CT,600PT2,605TD,902T,400PT2,402,902TD,900PT2. Install oil containment for 902T. Pull all new outdoor cable, modify cable tray, install new cable tray.
ATCO	10-Sep-24 10:00	10-Sep-24 17:00	7 Hours Continuous	801S 911, 801s 911 (801s Anderson)	Final connection of Bkr 911 52a single pole status inputs to DFR, Commission
ATCO	11-Sep-24 10:00	11-Sep-24 17:00	7 Hours Continuous	801S 912, 801s 912 (801s Anderson)	Final connection of Bkr 912 52a single pole status inputs to DFR, Commission
ATCO	07-Oct-24 10:00	21-Oct-24 17:00	14.29 Days Continuous	9L99, 9L99 (801s Anderson - 807s Sheerness)	Replace Breaker 901 @ 807S Sheerness, complete line 21A, 21B/9L99 protection upgrade and Commissioning
ATCO	11-Nov-24 10:00	25-Nov-24 17:00	14.29 Days Continuous	9L100, 9L100 (801s Anderson - 807s Sheerness)	Replace Breaker 902 @ 807S Sheerness, complete line 21A, 21B/9L100 protection upgrade and Commissioning
ATCO	05-May-25 09:00	30-May-25 17:30	25.35 Days Continuous	2029S BUILDING VALVE HALL, 2029s 1205 (2029s Heathfield), 2029s 1206 (2029s Heathfield)	Annual EATL outage at 2075s & 2029s. 2029s & 2075s AC & DC O&M. USE 2-70215 FOR 13L50 GOI USE 2-70216 FOR 2029s GOI USE 2-70217 FOR 2075s GOI
ATCO	05-May-25 09:00	30-May-25 17:30	25.35 Days Continuous	2075S BUILDING VALVE HALL, 2075s 916 (2075s Newell), 2075s 917 (2075s Newell)	Annual EATL outage at 2075s & 2029s. 2029s & 2075s AC & DC O&M. USE 2-70215 FOR 13L50 GOI USE 2-70216 FOR 2029s GOI USE 2-70217 FOR 2075s GOI
ATCO	05-May-25 09:00	30-May-25 17:30	25.35 Days Continuous	13L50 (DC LINK), 13L50 (2029s Heathfield - 2075s Newell)	Annual EATL outage at 2075s & 2029s. 2029s & 2075s AC & DC O&M. USE 2-70215 FOR 13L50 GOI USE 2-70216 FOR 2029s GOI USE 2-70217 FOR 2075s GOI
ATCO, Syncrude	20-May-25 09:00	12-Jun-25 10:00	23.04 Days Continuous	848S 910, 848S 911, 848S RL1 SYNCRUDE ISLANDING RAS (IRAS), RL1 (848s Ruth Lake - D05)	848S Ruth Lake Sub rebuild/upgrade protection to IEC 61850 - Cut over to new protection: 910CT,910,910B,910PT,RL-1D1,911B,911,911CT.
ATCO	12-Jun-25 11:00	04-Jul-25 09:00	21.92 Days Continuous	848S 911, 848S 913, 9L01 (848s Ruth Lake - 951s Thickwood Hills), 848s 911 (848s Ruth Lake), 848s 913 (848s Ruth Lake)	848S Ruth Lake Sub rebuild/upgrade protection to IEC 61850 - Cut over to new protection: 911,911CT,912B,9L01D1,913PT,913B,913,913CT
ATCO	04-Jul-25 11:00	24-Jul-25 09:00	19.92 Days Continuous	848S 905, 848S 906, 9L23 (848s Ruth Lake - 977s Salt Creek), 848s 905 (848s Ruth Lake), 848s 906 (848s Ruth Lake)	848S Ruth Lake Sub rebuild/upgrade protection to IEC 61850 - Cut over to new protection: 905CT,905,905B,905PT,9L23D1,906B,906,906CT,906A.
ATCO, SUNCOR	24-Jul-25 11:00	14-Aug-25 09:00	20.92 Days Continuous	848S 906, 848S 903, 848S 29PL9-1 SUNCOR ISLANDING RAS (IRAS), 29PL9-1 (29EDD-1 Millennium - 848s Ruth Lake), 848s 903 (848s Ruth Lake), 848s 906 (848s Ruth Lake)	848S Ruth Lake Sub rebuild/upgrade protection to IEC 61850 - Cut over to new protection: 906,906CT,904B,29PL9-1D1,903PT,903B,903,903CT.
ATCO, SUNCOR	14-Aug-25 11:00	04-Sep-25 09:00	20.92 Days Continuous	848S 901, 848S 902, 848S 29PL9-2 SUNCOR ISLANDING RAS (IRAS), 29PL9-2 (29EDD-1 Millennium - 848s Ruth Lake), 848s 901 (848s Ruth Lake), 848s 902 (848s Ruth Lake)	848S Ruth Lake Sub rebuild/upgrade protection to IEC 61850 - Cut over to new protection: 901CT,901,901B,901PT,29PL9-2D1,902B,902,902CT.
ATCO, Syncrude	04-Sep-25 11:00	25-Sep-25 09:00	20.92 Days Continuous	848S 902, 848S 907, 848s 902 (848s Ruth Lake), 848s 907 (848s Ruth Lake), RL2 (848s Ruth Lake - D05)	848S Ruth Lake Sub rebuild/upgrade protection to IEC 61850 - Cut over to new protection: 902,902CT,902A,902PT,RL-2D1,907A,907CT,907.
ATCO	25-Sep-25 11:00	17-Oct-25 14:00	22.13 Days Continuous	848S 907, 848S 908, 9L58 (848s Ruth Lake - 888s Dover), 848s 907 (848s Ruth Lake), 848s 908 (848s Ruth Lake)	848S Ruth Lake Sub rebuild/upgrade protection to IEC 61850 - Cut over to new protection: 907CT,907,907B,9L58D2,908PT,908B,908,908CT.

AB-BC, AB-SK & AB-MATL: refer to AESO web posting:	http://itc.aeso.ca/itc/public/atc
Also,
AB-BC, AB-SK & AB-MATL: refer to ISO Rule 203.6:	http://www.aeso.ca/rulesprocedures/18592.html
Prepared On:	2023-05-24   15:44:14

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