National Waste Services (LLWR Ltd.), UK

As part of the project to dispose of Treated Radwaste Store (TRS) drums at Repository site, dose rate calculations were needed to estimate the dose accrual from their emplacement in the Repository vault.

DEMplus® is a 3D simulation software package designed for nuclear projects developed by Cyclife Digital Solutions. It includes a deterministic dose calculation method for multiple sources and shields. In this case, DEMplus® was used as a method to cross check the primary dose rate calculation performed in MCNP6 (a Monte Carlo method).

Our proposal

  • A single drum was modelled, in DEMplus®, MicroShield and MCNP6. TRS drums consist of a cemented sludge sources, topped with a grout cap and contained within a steel drum.
  • The drums were modelled in their transport arrangement.
  • This comprised 12 drums located in a steel container, supported by wooden blocks. The 12 drums were also modelled outside the transport container in the same arrangement.
  • The final step was the modelling of the TRS drums emplaced in the Repository vault.

Customer benefits

  • Fast and easily checking measurement point, shield and source locations
  • Proven and safe solution


  • 1,000 TRS drums checked
  • Rail transfer to TRS drums to Repository site, out of the Geological Disposal Facility