PNNL

Abstract

A joint Russian and U.S. model intercomparison study was undertaken for developing more realistic contaminant transport models of the Mayak Site, Southern Urals. The test problems were developed by the Russian Team based on their experience modeling contaminant migration near Lake Karachai. The intercomparison problems were designed to address lake and contaminant plume interactions, as well as river interactions and plume density effects. Different numerical codes were used. Overall there is good agreement between the results of both models. Features shown by both models include 1) the sinking of the plume below the lake, 2) the raising of the water table in the fresh water adjacent to the lake in response to the increased pressure from the dense plume, and 3) the formation of a second sinking plume in an area where evapotranspiration exceeded infiltration, thus increasing the solute concentrations above the source (i.e., lake) values.