ORDER NUMBER
G-30-24
IN THE MATTER OF
the Utilities Commission Act, RSBC 1996, Chapter 473
and
Hemlock Utility Services Ltd.
Arc Flash Assessment - Variance to Order G-195-22
BEFORE:
B. A. Magnan, Commissioner
on February 2, 2024
ORDER
WHEREAS:
A. On August 4, 2023, Hemlock Utility Services Ltd. (Hemlock) filed a device coordination study report by Prime Engineering Ltd. and a submission on an arc flash assessment for the Hemlock system by Site Power Engineering Consultants (Site Power) to the British Columbia Utilities Commission (BCUC), in response to Directive 2 of Order G-195-22. Site Power submits that it is not practical to complete an arc flash assessment for the Hemlock system as directed under Order G-195-22 (Application);
B. By Order G-201-21 dated June 30, 2021, the BCUC ordered a hearing to review the safety and reliability of Hemlock’s electrical distribution system and system assets and customer service-related issues and established a regulatory timetable for the investigation. The BCUC issued Order G-195-22 and the accompanying Reasons for Decision on July 18, 2022;
C. Order G-195-22 directs Hemlock to, among other things:
Within 30 days of this Order, Hemlock is directed to file its most recent arc flash assessment and coordination study (Arc Flash Assessment) to identify and manage equipment hazards and identify protective trip curves. If an Arc Flash Assessment has not been completed, or was last completed over
5 years from the date of this Order, Hemlock is directed to perform and file an Arc Flash Assessment with the BCUC within one (1) year of this Order;
D. The results of the device coordination study indicate that Hemlock’s site main incoming fuse is adequately sized to accommodate additional load from the Sasquatch Mountain Resort;
E. Regarding the arc flash assessment, Site Power submits that it is not practical to complete an arc flash assessment for the Hemlock system for the following reasons:
i. an arc flash study requires consolidation of a system's attributes to a very high level of granularity.
As such, any necessary variances in system conditions due to required equipment replacements or changes in BC Hydro's system, will invalidate the arc flash assessment;
ii. Hemlock's operating procedures comply with WorkSafeBC & CSA Standard Z462 guidelines which provide specific information on safe work practices on energized equipment; and
iii. Equipment is de-energized prior to any maintenance or replacement work. In addition, work on other equipment such load-break switches and fuses will be conducted at a safe operating distance from any potential arc flash events; and,
F. The BCUC has reviewed the Application and determines that varying Directive 2 of Order G-195-22 to remove the requirement for an arc flash assessment, is warranted.
NOW THEREFORE pursuant to section 99 of the Utilities Commission Act, the BCUC orders that Directive 2 of Order G-195-22 is varied as follows:
Within 30 days of this Order, Hemlock is directed to file its most recent coordination study. If a coordination study has not been completed, or was last completed over 5 years from the date of this Order, Hemlock is directed to perform and file a device coordination study with the BCUC within one (1) year of this Order.
DATED at the City of Vancouver, in the Province of British Columbia, this 2nd day of February 2024.
BY ORDER
Original signed by:
B. A. Magnan
Commissioner