Location: North America
The challenge
Approximately 70% of commercial nuclear-generating stations in the U.S. have detected tritium in groundwater at concentrations exceeding the U.S. Environmental Protection Agency’s drinking water standard of 20,000 pCi/L. Detection of high concentrations poses reputational risks to an industry already facing stakeholder scrutiny, and signify that the plant is not operating as designed, resulting in questions on infrastructure aging, reactor safety and impacts on decommissioning planning. The Duke Energy’s H.B. Robinson Nuclear Plant in Hartsville needed to identify gaps and risks against commitments under NEI 07-07.
What we did
ERM developed a Site Conceptual Model to identify gaps and risks against commitments under NEI 07-07. The update reflected a site-wide assessment, incorporating data from multiple sources and interpreting the data in context of the overall objectives of NEI 07-07. Results were summarized into clear graphics, including time-series plots and aerial photographs. An ArcGIS site was developed to access the Site Conceptual Model graphics through a secure website, allowing Robinson staff to generate their own figures and for use as a communications tool. In addition, ERM successfully installed 11 new monitoring wells to allow for early detection downgradient of high-risk sources. Multi-level wells were installed in order to quantify downward flux of shallow groundwater into a deeper aquifer that is currently used as a source of plant cooling water.
The impact
RM’s Site Conceptual Model report for Robinson Nuclear Station was well received by an NRC inspector after the station reported a small interior leak within the spent fuel pool. ERM presented findings at the Groundwater Steering Team meetings at Robinson, informing plant management of the current status and future direction of the groundwater protection program.
