ML13164A294

6/3/13 - NRC Response to Mary Lampert Concerning Air Leakage Into the Condenser at Pilgrim

ML13164A294
Person / Time
Site:	Pilgrim
Issue date:	06/03/2013
From:	Fred Bower NRC/RGN-I/DRP/PB5
To:	Lampert M - No Known Affiliation
Bower F
References
Download: ML13164A294 (2)

Text

From: Bower, Fred Sent: Monday, June 03, 2013 10:17 AM To: 'Mary Lampert' Cc: Roberts, Darrell; Layton, Michael; Lew, David; Dean, Bill; Noggle, James

Subject:

RE: Still thinking about the air leakage into the condenser.

Hello Mary, My name is Fred Bower and I am currently the acting chief of the Region I branch (BR 5) that includes Pilgrim. Bill Dean asked me to provide you with some additional information to that you have received from Dave Lochbaum.

My understanding is that, at Pilgrim, the air flow through the Advanced Offgas System is controlled by the ventilation exhaust fans - not variable based on air in-leakage into the condenser, so the gas residence time would not be reduced.

Dave provided you a good description of the radiation detectors and I would only add that these gaseous effluent radiation monitors have set-points that, when exceeded, isolate the gaseous release. These set-points are set based on the radionulide mixture and are set to ensure the instantaneous effluent release rate concentrations are less than the regulatory limits in 10 CFR 20, Appendix B. Also, surveillance tests are performed on these monitors daily to ensure that they are functioning properly.

Thank you, Fred Bower From: Dean, Bill Sent: Friday, May 31, 2013 4:25 PM To: Mary Lampert Cc: Bower, Fred; Roberts, Darrell; Layton, Michael; Lew, David

Subject:

RE: Still thinking about the air leakage into the condenser.

Hot here too, and not from nearby Limerick operations. I will have someone get back to you Mary (hopefully before Dave does!) regarding effluent impacts of air in leakage. Besides annual reports, there obviously is on line, real time monitoring and the system is designed to absorb a certain amount of air in leakage and not have any issues akin to what you are describing relative to long vs. short lived isotopes.

BILL Bill Dean Regional Administrator Region I From: Mary Lampert [1]

Sent: Friday, May 31, 2013 4:15 PM To: Dean, Bill

Cc: Dave Lochbaum

Subject:

Still thinking about the air leakage into the condenser.

Hello again:

Still thinking about the air leakage into the condenser.

The way that I understand it, the air speeds up the radiation flow though the AOG hold up system - so the release rate time is lessened - that means the radiation does not hang around the charcoal as long and has less of a decay factor with an end result the radiation released is higher that it should be.

It is not comforting to know that simply Entergy provides Annual Effluent Reports- averages do not tell me what is happening today.

Further, I understand that the radiation detectors are sensitive only to the total amount of radiation hitting them - they do not differentiate between one isotope and another. One fundamental limitation to measuring gamma radiation levels exiting Pilgrims ventilation systems is that a relatively large amount of long-half life isotopes would result in a small perturbation in the total amount of radiation detected, since the decay rate is so much slower compared to the short half-life isotopes. In this way a leak of long half-life isotopes could go undetected by a radiation detector. Correct me if I am wrong here. If I am correct, then why is Pilgrim operating until this is fixed considering the public health implications?

Thanks, Mary PS It is hot here and beaches likely to be packed over the week-end.