Hydrocarbon spills can contaminate soil with e.g. phenantrene or naphtalene. Microorganisms can be used to metabolize or co-metabolize pollutants to perform a clean-up. The Pace determining step is usually the diffusive process in the soil's grains. Loading and washing/unloading of soil samples can serve to identify diffusion and sorption parameters which in turn will permit to simulate bioremediation progress. At www.environment.report we have a 10+ years track record in coding such simulations and associated graphical user interfaces.