UCD McClellan Nuclear Radiation Center

Neutron detectors and control panels transferred from Rocky Flats Plant (RFP) were recalibrated and retested for redeployment to the CEF. Testing and calibration were successful with no failure to any equipment. Detector sensitivity was tested at the TRIGA reactor, and the response to thermal neutron flux was satisfactory. MCNP calculated minimum fission yield (~ 2 × 1015 fissions) was applied to determine the thermal flux at selected detector positions at the CEF. Thermal flux levels were greater than 6.39 × 106 (n/cm2-sec), which was about four orders of magnitude greater than the minimum alarm flux. Calculations of detector survivable distances indicate that, to be out of lethal area, detector needs to be placed greater than 15 ft away from the source. MCNP calculated flux/dose results were independently verified by COG. CAAS calibration and the testing confirmed that the RFP CAAS system is performing its functions as expected. New criteria for the CAAS detector placement and 12-rad zone boundaries at the CEF are established. All of the CAAS related documents and hardware are transferred from LLNL to NSTec for installation at the CEF high bay areas.