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What We Heard Report – DIS-12-01

Protection of Groundwater at Nuclear Facilities in Canada


Discussion papers play an important role in the selection and development of the regulatory framework and regulatory program of the Canadian Nuclear Safety Commission (CNSC). They are used to solicit early public feedback on CNSC policies or approaches.

The use of discussion papers early in the regulatory process underlines the CNSC’s commitment to a transparent consultation process. The CNSC analyzes and considers preliminary feedback when determining the type and nature of requirements and guidance to issue.


The CNSC’s mandate is to ensure the environment is protected from potentially harmful effects of regulated nuclear activities. In discussion paper DIS-12-01, Protection of Groundwater at Nuclear Facilities in Canada, the CNSC set out a proposed approach to current licensees and applicants for new nuclear facilities in Canada to help ensure the protection of groundwater. The facilities included in the scope of the discussion paper were Class I nuclear facilities, uranium mines and mills and nuclear waste management facilities.

Consultation process

DIS-12-01 was initially posted on the CNSC website for a 60-day consultation period from February 17, 2012 to April 16, 2012. At the request of stakeholders the consultation period was extended to June 30, 2012.

Following the consultation period, submissions from stakeholders were posted on the CNSC website from July 30, 2012 to September 13, 2012 to allow interested parties to provide feedback on the comments received.

The CNSC received 16 written submissions. Submissions from stakeholders can be found in a report that summarizes the results of the CNSC’s preliminary public consultation on the protection of groundwater at nuclear facilities.

Summary of stakeholder comments

  • Most comments were requests for clarification of terms and definitions used in the document.
  • While there was broad agreement with the principles outlined in the discussion paper, there was some disagreement as to the specifics of the proposed groundwater monitoring program. In addition, there was concern that the proposals may already be covered by existing provincial and federal legislation.
  • There were suggestions to use the CSA Group to address the details of designing a groundwater protection and monitoring program for Class I nuclear facilities, uranium mines and mills, and nuclear waste management facilities to meet the expectations outlined in the discussion paper.

Controlling releases

  • There was general agreement that controlling releases from regulated facilities is a worthwhile goal as a high-level principle. However, the CNSC was advised that the precautionary principle should be applied when managing the risks of releases of nuclear and hazardous substances which have not been fully characterized.

Assessing end use and vulnerability

  • All who commented supported, to varying degrees, the identification of the end use of the groundwater. Some commented that if there was no identified end use, then the risk assessment to demonstrate protection of aquatic and terrestrial environments should be applied at and beyond the point at which groundwater flows back into the surface environment (e.g., into a lake or stream fed by groundwater discharge).

Site characterization

  • Some of those commenting preferred the adoption of a tiered approach, to ensure the information requirements for site characterization would be proportional to the potential risks. Others indicated that site characterization should also include an assessment of the site’s baseline and background water chemistry, since concentrations of naturally occurring chemicals may sometimes exceed water quality standards for end use.

Characterizing sources of releases

  • When identifying contaminants of potential concern, it was noted that reaction products (created when a contaminant reacts with another chemical in the ground) should be considered. Similarly, daughter products of substances with short half-lives should also be considered.

Implementing a groundwater monitoring program

  • Some respondents suggested that groundwater monitoring program requirements would be best developed by the CSA Group.

Investigation and remediation of unauthorized releases

  • A view was expressed that the investigation and remediation of unauthorized releases is already sufficiently regulated by existing provincial and federal legislation. Some believed that the requirement to remediate should be case- and site-specific.

CNSC implementation and evaluation

  • It was suggested that there should be requirements for notifying the CNSC during implementation of groundwater monitoring programs, and for the use of adaptive management plans. This would result in groundwater monitoring programs being updated as more monitoring data are acquired.

Next steps

The CNSC will draft a regulatory document on groundwater protection, taking into account all comments received during the public consultation on Discussion Paper DIS-12-01. A draft document is anticipated in 2014 for public comment. In parallel, the CNSC continues to work with the CSA Group to develop a complementary standard on groundwater protection programs at Class I nuclear facilities and uranium mines and mills. The public will be invited to comment on the standard by the CSA Group, as part of its normal public consultation on draft standards.

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