German technical support organization, GRS, has won funding from the Federal Environment Ministry to carry out research and development relating to the two-phase flow of radionuclides in a repository in salt.

The three-year project, ZIESEL, will run from 2013 through 2016, GRS said.

Work will involve validation/refinement of the TOUGH2 (Transport of Unsaturated Groundwater and Heat) computer code, which is used for modeling the transport of radionuclides contained in solutions and gases through rock.

TOUGH2 was developed at the Lawrence Berkeley National Laboratories in the United States and GRS has been using and optimising the code for more than 20 years.

"Despite the fact that there is long-standing experience with two-phase flow models, they are only rarely used," GRS said. For future analyses, for example in the repository site selection process, it will be necessary to test this approach using the example of a real site.

In this latest project, GRS says it will use data from the Morsleben Repository for Radioactive Waste, which currently stores 36,745 cubic metres of low- and medium-level waste, in order to test the code.