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Guaranteed Defuelled State of Pickering A Units 2 and 3

Environmental assessment start date: February 4, 2008
Type: Screening
CEAR reference number: 08-01-37538
Proponent: Ontario Power Generation
Location: Pickering Nuclear Generating Station A (Ontario)

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Project Description

The Canadian Nuclear Safety Commission (CNSC) has received notice of intent and a project description from Ontario Power Generation (OPG), indicating its intent to place Pickering A Unit 2 and Unit 3 into a Guaranteed Defuelled State. 

In the Guaranteed Defuelled State, Pickering A Units 2 and 3 would be physically separated from Units 1 and 4 and from the essential systems required for the continued safe operation of Units 1 and 4.  The proposed Guaranteed Defuelled State of Units 2 and 3 is intended to ensure that these Units cannot be returned to service.

Changes to Pickering A identified in OPG’s project description that would result in Units 2 and 3 being in the Guaranteed Defuelled State include:

  • permanently relocating the reactor building containment boundaries for Units 2 and 3 (permanently isolating the Unit 2 and 3 reactor buildings from the pressure relief duct, taking airlocks out of service, and physically changing the reactor building ventilation system);
  • physically separating Units 2 and 3 from the Emergency Coolant Injection System (cutting and capping material lines to the ECI system, and removing relevant communication links); and
  • moving vacuum building alarms and annunciations( reconfiguration of the Unit 1 control panel).

CNSC approval of the proposed Guaranteed Defuelled State requires amendments of OPG’s Power Reactor Operating Licence pursuant to subsection 24(2) of the Nuclear Safety and Control Act (NSCA).

Before the Commission may consider a decision on licensing under the NSCA regarding OPG’s proposal, an environmental assessment must be completed in compliance with the Canadian Environmental Assessment Act (CEAA). The purpose of an environmental assessment is to identify the possible environmental effects of a proposed project, and determine whether these effects can be mitigated. The environmental assessment to be completed under the CEAA will provide part of the information that the Commission will use in considering OPG's proposal.

Further Information

CNSC maintains a public registry of documents related to its environmental assessments. Lists and copies of documents may be obtained upon request. For questions or information directly related to this environmental assessment, contact the CNSC.

CNSC regulates the use of nuclear energy and materials to protect health, safety, security and the environment and to respect Canada's international commitments on the peaceful use of nuclear energy.

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