PNNL

This seminar will offer a technical overview of current methodologies, lessons learned, and ongoing efforts to address environmental liability at legacy waste management areas within a regulated nuclear environment.

The Chalk River Laboratories site, located in Chalk River, Ontario (Canada), includes several complex legacy landfills that present significant challenges for environmental characterization and remediation. These sites, affected by historical nuclear and non-nuclear waste disposal practices, require integrated, science-based approaches involving radiological and conventional contaminant assessment, geotechnical investigation, excess soil management, and risk-informed decision-making. Characterization strategies are designed to support regulatory compliance, long-term site stewardship, and alignment with evolving environmental protection standards.

Attendees will gain insights into the following topics:

• The evolution of internal programs and processes that integrate environmental considerations across decommissioning and site revitalization activities.
• The assessment and management of conventional contaminants using environmental site assessment tools, human health and ecological risk frameworks, and remediation planning.
• The development and application of site/media-specific scaling factors utilizing data from easier-to-measure radionuclides to estimate the relative quantity of difficult-to-measure isotopes—an approach adapted for the complexities of legacy environmental contamination. These data can then be used to estimate the radiological contaminants of concern within a site, informing risk assessment and remediation planning.
• The benefits as well as the practical and regulatory challenges of adopting non-nuclear regulations to manage excess soil on an active nuclear site. The Soil Management Process was introduced last year and provides a flexible framework for a variety of projects and jobs to implement sustainable and practical solutions to reduce, reuse, and divert excess soil from waste streams. This can help keep project schedules on track and eliminate unexpected costs.

Presenters

• Lucia Valente, land use program officer, Canadian Nuclear Laboratories (CNL)
• Ariel Nunez Garcia, environmental remediation specialist, CNL
• Stephanie Thomson, environmental remediation specialist, CNL
• Sonja Lindberg, environmental specialist, CNL

Facilitators

• Nik Qafoku, PhD, deputy director of outreach, RemPlex
• David Yuke, environmental remediation project leader, CNL

Contact remplex@pnnl.gov for more information.