Groundwater Model for Sellafield Case Study
Project: Development of a groundwater model for the Sellafield site
Client: British Nuclear Group
The Challenge
Many years of operation at Sellafield have left the site operator with a number of problems with respect to contamination of groundwater resulting from leaks to ground. Dealing with the problem successfully is a major uncertainty associated with the cost of clean-up of the Sellafield site within the programme of the Nuclear Decommissioning Authority. The site operator is also challenged by the site regulators with respect to routine operations and the ongoing environmental performance of the site.
British Nuclear Group needed a hydrogeological model of the site to assist with decision-making processes for developing groundwater monitoring programmes for the site and for developing groundwater flow and transport models used for risk assessments of contaminated land in specific areas of the site.
The Solution
Working closely with the client, and using our expert scientific knowledge of the site, we developed a 3D groundwater flow model of the site. In particular, we:
- reviewed our earlier work on the geology and hydrogeology of the site, particularly our lithological block model of the site;
- recreated the block model within the Visual ModFlow user interface to ModFlow, correlating the lithological units to individual elements of the model;
- parameterised the hydrogeological performance of model to known properties for the main component of each element;
- calibrated the model against existing field data, then validated the model against more recent data.
The Benefits
- The new model allows the production and substantiation of simpler assessment level models for risk assessments at the site
- The model assists our client with their ongoing communication with the regulator on in-ground contamination issues at the site.
- The model has allowed WSC to predict contaminant fate for rapid / emergency assessment of leaks to ground and assess contaminant release / transport scenarios on the Sellafield site.
