NPD Vault Entry

The Distinguished Merit Award is awarded to:

Robby Baidwan, Ian Donohue, Thomas Heale, Mitch King, Andrew Kittmer, Kevin Milks, and Terry Schaubel for developing specialized tooling used to access the Nuclear Power Demonstration (NPD) reactor vault for general inspections – a critical step in the decommissioning of NPD.  The team assessed the optimal means to access the vault, reviewed historic records to verify constraints, developed and tested custom equipment to achieve the objective, planned the work with strong attention to detail, and executed the work flawlessly.  An access hole was produced by coring vertically through nine feet of reinforced heavy concrete, while avoiding items such as an active drain line, vault dousing system piping, and structural components.  This access allowed an inspection of the reactor vault in order to determine its general condition and the in-vault radiation levels.  Samples of the vault liner material were also obtained, to help further characterize the state of the facility, in support of planned decommissioning activities.

The work was challenging in many ways. The use of cooling water was strictly minimized and a novel water recirculation method was employed. Cores had to be recovered and carefully accounted for. This was especially difficult as coring progressed and the pieces had to be retrieved from a depth of nine feet. Foreign material entry into the vault had to be minimized. This was especially challenging for the final material being removed since gravity would tend to cause the pieces to fall out of reach into the reactor vault. Special tooling was developed to capture these difficult pieces. The location of the core had to be very carefully planned to avoid obstructions in the structure and dousing tank. And with the configuration of the reactor difficult to establish and old, incomplete drawing sets, the task was further complicated. There was very little room for error, and the work was completed safely, efficiently and without issue.