Intrinsic Nuclear Security Attribute Analysis for Physical Protection System Development of Reaktor Daya Eksperimental
Dany Mulyana

Center of Nuclear Security Science and Policy Institute, Texas Engineering Experiment Station, Texas A&M University, College Station, TX, USA.

Abstract

A study on material theft analysis of fresh and spent fuels of Reaktor Daya Eksperimental (RDE) has been completed. This study covers an integrated analysis of nuclear safety, security, and safeguards. This study assumed that each pebble fuel contains about 7,223 tri-structural isotropic (TRISO) fuel kernel microspheres depleted up to 90 GWd/MTU. Both the TRISO and the graphite matrix of the fuel pebble was designed to contain fission products during and after irradiation. A set of Monte Carlo n-Particle (MCNP) neutronic simulations on the RDE^s fresh and spent fuel pebbles were completed to investigate the potential radiation exposure to the personnel, that can be a security barrier for RDE system. Taking only gamma ray into considerations, this study found that the fresh fuel pebble containing 5 g of UO2 enriched to 17 wt% of U-235 exposes radiation with a dose rate of only 0.38 microrem/h at a distance of 1 m away from the pebble. At the same distance, a 90 GWd/MTU spent fuel pebble cooled for one year resulted dose rate of about 1.0 rem/h. This study also found that a lead sphere shielding (density of 11.34 g/cm3) with a thickness of approx. 12.5 cm must cover the spent fuel pebble to reduce dose rate to 0.328 microrem/h.

Keywords: Nuclear Security, Physical Protection System, Pebble Bed Reactor, Reaktor Daya Eksperimental

Topic: Nuclear Nonproliferation Issues