Safety and Three Mile Island

Two concurrent evaluations were made for all probable (and a few improbable) fliel configurations that could be identified. One was made by reactor physics personnel using mactor design codes, while the other was made by nuclear criticality safety specialists using criticality safety codes. In addition to evaluating specific fuel configurations, basic data Such as K-infinite vs fuel-to-water ratios were tabulated for different enrichments, fuel particle sizes, water temperatures, boron levels, etc. 

In conclusion, the TMI-2 core is subcritical with a more than adequate safety margin. Subcriticality can be easily maintained flirou control over the amount of boron dissolved in the primary coolarit system water. 

WELFARE, Ed.. BAW Version of ORNL Otde KENO IV L. M. PETRIE and N. F. CROSS, An Improved Monte Carlo Criticality Program, ORNL-4938 (Nov. 1975), NPGD-TM 503 (Apr. 1979). 

WITTKOPF et al., NUUF-A Neutron Spectrum Generator, Few Group Constant Calculator and Fuel Depletion Code, BAW-10115 (Mar. 1976). 

GREENE et al., AMPX-A Modular Code Syston for Generating Coupled Multigroup Neiitron-Gamma ybraries from ENDF/B, ORNL/TM-3706 (Mar. 1976). 

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