Letter: CNSC authorizes removal of Regulatory Hold Point 4 for Darlington Unit 2

Regulatory Operations Branch

May 13, 2020

Mr. Dietmar Reiner Senior Vice President, Nuclear Projects Ontario Power Generation Inc. 1855 Energy Drive, 3C14 Courtice, ON L1E 0E7

Mr. Steve Gregoris Senior Vice President, Darlington Nuclear Ontario Power Generation Inc. P.O. Box 4000 Bowmanville, ON L1C 3Z8

SUBJECT: Darlington NGS - Unit 2 Return to Service: Request for CNSC Consent to Remove the Regulatory Hold Point for Reactor Power Increases Prior to Exceeding 35% Full Power

Dear Messrs. Reiner and Gregoris,

The purpose of this letter is to respond to the request [1] from Ontario Power Generation (OPG) to remove Regulatory Hold Point 4 (RPH-4), allowing OPG to proceed with operation above 35% full power in the refurbished Unit 2 reactor at the Darlington Nuclear Generating Station (DNGS). As established in DNGS Power Reactor Operating Licence (PROL) 13.02/2025 and its accompanying Licence Conditions Handbook, LCH-PR-13.01/2025 R003, RHP-4 marks the last hold point in the return to service of Unit 2 requiring Canadian Nuclear Safety Commission (CNSC) approval or consent to be removed.

CNSC staff assessments [2, 3] concluded that OPG has met all the pre-requisites established by the Commission to remove RHP-4. Therefore, as the person authorized by the Commission and pursuant to Licence Condition 15.4 of the DNGS PROL, I hereby consent to the removal of RHP-4, allowing OPG to operate the Darlington Unit 2 reactor above 35% full power.

Yours sincerely,

Ramzi Jammal
Executive Vice-President and
Chief Regulatory Operations Officer
Regulatory Operations Branch

c.c: G. Frappier, J. Burta, P. Elder, D. Newland, G. Lamarre, M. Rinker, K. Heppell-Masys, H.Tadros, C. Loreti, D. Desjardins, D. Nguyen, N. Abonasara, K. Hazelton, A. Mathai, C. Yacoub, Darlington Site Office

References:

1. OPG letter, D. Reiner and S. Gregoris to R. Jammal, “Darlington NGS Refurbishment – Unit 2 Return to Service: Request for CNSC Consent Prior to Exceeding 35% Full Power (RHP 4)”, May 11, 2020, NK38-CORR-00531-21631.
2. CNSC staff document entitled: “Request by Ontario Power Generation Inc. to Remove Regulatory Hold Point for Reactor Power Increases Prior to Exceeding 35% Full Power for Unit 2”, dated May 7, 2020.
3. CNSC staff memorandum entitled: “Removal of Regulatory Hold Point (RHP-4) for Reactor Power Increases Prior to Exceeding 35% Full Power for Darlington NGS Unit 2”, dated May 13, 2020.