Re: GM response to neutrons?

[NSSIHOU@AOL.COM]

While I agree with the statements of the other commenters concerning the source of gammas being detected by your gamma survey instrument, there is another source of gammas that no one has addressed. Keep in mind that most neutron sources in use for well logging applications these days are 4e+6 to 2e+7 neutrons out put. Also, keep in mind that the source material is contained within capsules designed for corrosion resistance and high pressure. This generally means capsules with high cobalt content. Placing a high cobalt content material in close proximity to E+6- E+7 neutrons 24 hours a day for up 20 years yields a significant source of activation and its associated gammas. 


When we receive neutron sources for disposal, we often must cut out the center cavity of the transport shield and dispose of the pressure vessel and center insert as radioactive dry waste. 


Robert D. Gallagher

NSSI

713 641-0391