MCNP Case Study – Dry Cask Shielding

March 28, 2017

One year ago we introduced our new ability to simulate complex radiation profiles and thereby design the most effective shielding possible (‘NPO uses MCNP to simulate Dry Cask’, March 2016).  Since then we’ve designed and built more than a few shielding systems using this new ability.  Now the day has finally come where we can […]

Neutron Shielding – Borated Polyethylene

August 31, 2016

Borated Polyethylene (BPE) is one of the primary materials NPO uses for shielding Neutron Radiation. Our standard BPE is 5% Boron by weight. The benefit of adding Boron is that capture by B-10 reduces the dose from secondary gamma production. It primarily captures through (n, alpha), and the alphas are easily re-absorbed in the material. […]

Braidwood Dry Cask Annulus Gap Snakes

June 9, 2016

Exelon Braidwood Station recently saw very good dose reduction with their dry cask campaigns by utilizing NPO T-Flex® Annulus Gap Shielding. This was designed to fit in the annulus gap between the canister and transfer cask and had a fire blanket covering specified by Braidwood. The annulus gap shielding, in addition to more NPO dry […]

Lower Dry Cask Barrel Shield

March 9, 2016

Some NPP’s process Dry Casks in a such a way that the entire cask produces a general area dose concern. To reduce these dose rates NPO developed a shield package that sits on the floor and shields the cask to a height of 9 feet. NPO is currently under contract to provide shield package with […]

NPO uses MCNP to simulate Dry Cask

Dry Cask processing operations present a number of complex radiological challenges. The presence of both neutron and gamma radiation coupled with the varying amounts of shielding already provided by the cask and canister make it difficult to know where to put shielding and what type shielding to use. Additionally, shielding limitations often exist in the […]