July 15, 2024

Canadian Nuclear Laboratories (CNL) is Proposed Change to the PHAI Cleanup Criteria for Arsenic

Image Supplied by PHAI

PHAI Project Change

Canadian Nuclear Laboratories (CNL) is proposing a change to the PHAI Cleanup Criteria for arsenic. This non-radioactive contaminant is associated with the processing of historic low-level radioactive waste in Port Hope. As part of Port Hope Area Initiative (PHAI) activities, the waste is being cleaned up and sites remediated to meet specific levels for contaminants as set out in the Waste Nuclear Substance License, the regulatory document overseen by the Canadian Nuclear Safety Commission (CNSC).

Through experience cleaning up public and private properties in Port Hope, CNL determined that the cleanup criteria level for arsenic is resulting in more extensive and lengthier cleanups than originally anticipated. In addition, analysis has shown that the current criteria will create significant unintended project impacts to the natural and built environment, including a noticeable loss of trees in the municipality, unless it is amended.

In March 2020, CNL submitted an application to the CNSC to amend the PHAI Cleanup Criteria to address these concerns. Based on preliminary regulatory feedback, the application was withdrawn and a revised application is expected to be submitted in 2023.

A risk-based approach is being used to identify a potential new cleanup criteria level for arsenic. Working with multiple federal and provincial agencies adds an element of rigour that has extended the time frame to determine a new criteria level that is protective of human health and the environment.


What is the issue?

Analysis of 30,000 soil samples has determined that a significant number of property cleanups are being driven by low levels of arsenic in soil, rather than radioactive contaminants, resulting in unintended impacts:

  1. Property cleanups take longer and are more extensive, causing residents distress about the impact on their properties.
  2. Cleanups have a greater impact on Port Hope’s tree canopy, raising community concern about the effect on the natural environment.
  3. More properties will require a cleanup than anticipated, extending the schedule of the PHAI.

How will the change help?

The proposed changes will reduce unintended project impacts, while still being protective of human health and the environment, by:

  • Shortening the timeline and extent of excavation on many properties
  • Requiring the removal of fewer trees, especially in areas with mature trees
  • Reducing the number of properties requiring a cleanup, which will shorten the duration of the PHAI in Port Hope

What can I do?

Learn more

  • For more information on the cleanup criteria change and associated risks go to Staff are also available by email or by phone to answer your questions.

Attend an information session

  • CNL is hosting public engagement sessions, virtually and in person, to get community feedback. Contact us to find out how you can participate in a discussion group.

Give your feedback

  • CNL anticipates having the cleanup criteria change addressed at a public hearing of the CNSC. In the meantime, you can provide comments directly with a feedback form available on or at 25 Henderson Street.

The proposal to amend the PHAI Cleanup Criteria is supported by Atomic Energy of Canada Limited, the Crown corporation responsible for fulfilling Canada’s commitment under the PHAI Legal Agreement. CNL is committed to completing the community-requested cleanup safely and compliantly.

Sponsored Post


Leave a Reply

Your email address will not be published. Required fields are marked *