A next generation open source subsurface simulator and user environment for
environmental management is being developed through a collaborative effort across Department of
Energy National Laboratories. The flow and transport simulator, Amanzi, will be capable of
modeling complex subsurface environments and processes using both unstructured and adaptive
meshes at very fine spatial resolutions that require supercomputing-scale resources. The user
environment, Akuna, provides users with a range of tools to manage environmental and simulator
data sets, create models, manage and share simulation data, and visualize results. Underlying the user
interface are core toolsets that provide algorithms for sensitivity analysis, parameter estimation, and
uncertainty quantification. Akuna is open-source, cross platform software that is initially being
demonstrated on the Hanford BC Cribs remediation site. In this paper, we describe the emerging
capabilities of Akuna and illustrate how these are being applied to the BC Cribs site
