Horizon Mining 838S Substation Modification

Canadian Natural Resources Limited (CNRL)has applied to the AESO for transmission system access to relocate an existing 240 kV transmission linein the Fort MacKay area. CNRL’s request can be met by the following solution:

• Modify the existing Horizon Mining 838S substation including adding six 240 kV circuit breakers.
• Add two segments of 240 kV transmission line (9L32 and 9L66) between the Horizon Mining 838S substation and the existing 240 kV transmission lines 9L32 and 9L66.
• Remove a segment of the existing 240 kV transmission lines 9L32 and 9L66 between the existing Joslyn 849S substation and the connection point with the new segments of 9L32 and 9L66.
• Add or modify associated equipment as required for the above transmission developments.

Need Overview

• Need for the Horizon Mining 838S Substation Modification in the Fort MacKay Area [Posted: Nov. 10, 2020]

Notice of Filing

• Notice of Filing for the Horizon Mining 838S Substation Modification [Posted: April 6, 2021]

Needs Identification Document

Horizon 838S Substation Modification Needs Identification Document Checklist [Posted: July 16, 2021]

Attachment A - TFO Capital Cost Estimate
Attachment B - Single Line Diagrams