A decommissioning plan for the Heavy Water Components Test Reactor

Three alternatives to decommission the Heavy Water Components Test Reactor (HWCTR) have been analyzed as summarized in Table 1. The protective confinement approach is advantageous as long as current activities onsite limit access by the general public; excellent confinement of the residual activity is provided by in situ dry storage as the radiation from {sup 60}Co diminishes. Entombment provides the most-secure confinement of the activity but at some increased cost. Dismantling HWCTR has no apparent advantages other than a demonstration at the Savannah River Plant site, because of the long-term commitment to safeguarding radioactive material; the relative cost is high. The induced radioactivity in HWCTR is current 2.3 {times} 10{sup 4} Ci; general area radiation levels are typically 3 mR/hr. In 35 years, the decay of {sup 60}Co will lower the radiation levels by a factor of 100, and the remaining radioactivity will be 2 {times} 10{sup 3} Ci of {sup 63}Ni. Minimal offsite effects are calculated to result after postulated structural failures to the decommissioned HWCTR facility. Flexibility and aesthetics favor dismantlement, but these criteria are considered less significant than public radiation dose, cost, and land area committed