The Laptev sea in the Russian Arctic receives organic rich sediments from both erosion of coastal cliffs and from the Lena river, the worlds 13th largest by discharge, which drains a large permafrost rich area of the Asian continent. These sediments differ both in their physical characteristics and in the bioavailability of their carbon. The comparative distribution and residence time of these two sediment types will therefore have an impact on the shelf biogeochemistry. We use the unstructured grid hydrodynamic model FVCOM to model the Laptev sea around the Lena outflow. Output from this model drives a simple model of sediment tracers, with seperate classes for coastal and riverine input. Existing sediment observations are used to calibrate the model setup. This setup is used to study the spatial distribution and residence times of the two sediment sources both under current conditions and under a future scenario reflecting the expected change in freshwater input and ice cover.