"I don't think the NRC
staff has any idea what would really happen if they had a geyser coming out of the reactor vessel head," Dr. William R. Corcoran
, head of Nuclear Safety Concepts in Windsor, Conn., said yesterday.NRC
staff did the analysis in response to questions about the rust hole discovery in the reactor head in March at FirstEnergy Corp.'s
Davis-Besse plant along Lake Erie near Oak Harbor.
The questions were submitted jointly by Rep.
said the NRC analysis did not fully consider phenomena that might have occurred in a hole-through-the-head accident.One, for instance, would be collateral damage caused by a high-pressure geyser of water pouring out of the hole in the reactor vessel.He
said a geyser could tear loose insulation, mechanical components, and other material.The material could fall to the containment building floor along with the spilled reactor cooling water.
During the first 30-45 minutes of such an accident, reactor operators draw emergency cooling water from a special tank inside the containment building.When the tank empties, they start recirculating the spilled water by sucking it through a drain, or "sump," in the floor of the containment building.Dr. Corcoran
said material ripped loose by the geyser might plug the sump, cutting off emergency core cooling water and leading to a meltdown.
...Dr. Corcoran holds a doctorate in nuclear engineering from the Massachusetts Institute of Technology.He served in the U. S. Navy's nuclear submarine program, chaired the American Nuclear Society's reactor safety division, and was director of safety analysis for Combustion Engineering, a nuclear power plant manufacturer.