Re: rad leak in upstate NY? -Reply

["Bernard Quinn" <bquinn@safety.rochester.edu>]

As the HP at Ginna during the tube rupture event, here are a few 
details as I remember them. On January 25,1982 there was a reactor 
trip and safety injection due to a tube rupture in one of two steam 
generators. The reactor coolant was immediately degassed through the 
steam generator,  to the steam and through the turbine to the 
condenser (30 inch vacuum) and out the air ejector. About 90 Curies 
of noble gas, mainly Xe-133 was released through this path.

The event resulted in the declaring of an "Alert" emergency 
condition and if the reactor would have been brought to a cold 
shutdown this would have been the end of the releases and the 
incident. However while trying to reestablish the proper level in the 
pressurizer a valve malfunctioned after several operations. This 
resulted in having to restart pumps which raised the pressure too high in 
the steam line which was water solid at this point. One of the main 
steam safety valves lifted a few times giving a two phase release of 
water and steam. The water in the steam line was reactor coolant 
diluted by the volume in the steam generator. A site emergency was 
declared, not based on releases, but what the plant superintendent 
judged was the degrading condition of the plant.

The release of water was mainly to the immediate area outside the 
containment building and onto the containment dome itself. The 
contaminated steam was virtually all condensed by the time it reached 
the site boundary. It was snowing at the time and the temperature was 
12 degrees F. About 3000 gallons of water and steam was released with 
activity of about 0.001uCi/ml.

A lot of the snow around the reactor building was scooped up and 
placed in what was a large swimming pool type bunker in a radwaste 
building. When it melted the drain collection tank was sampled and 
released.

A problem at the time was the lack of a standard snow sampling 
procedure which is necessary to do good deposition measurements. How 
deep do you sample?

Doses based on worst case scenarios were a few millirem. A extensive 
survey of the site was performed along with some offsite areas. Only 
traces of tritium could be found offsite. So much for the "Worst 
nuclear plant accident since Three Mile Island" in the ominous tones 
of Walter Cronkite.


Bernie Quinn, CHP
Health Physicist
University of Rochester