ML20082Q812
| ML20082Q812 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 12/06/1983 |
| From: | Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | Harold Denton, John Miller Office of Nuclear Reactor Regulation |
| References | |
| 450-C, NUDOCS 8312120353 | |
| Download: ML20082Q812 (3) | |
Text
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I VIHOINIA ]$LECTHIC AND I'OWEH COMPANY IIIC11MOND, YIHOINIA 2 0 2 61 W. L. STvtwAuf xE="d"[='"EI,==
December 6, 1983 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation Attn: Mr. James R. Miller, Chief Serial No.
450C Operating Reactors Branch No. 3 PSE&C /HSM/Imf/0013N Division of Licensing Docket Nos.
50-338 U.S. Nuclear Regulatory Commission 50-339 Hashington, D. C, 20555 License Nos.
NPF-4 NPF-7 Gentlemen:
ADDITIONAL INFORMATION PROPOSED OPERATING LICENSE AMENDMENT NPF-4 AND NPF-7 NORTH ANNA POWER STATION UNIT NOS. 1 AND 2 In a recent telephone conversation between members of your staff and Vepco, clarification was requested on our response to question 1 in our letter of June 16, 1983 (Serial No. 4508).
The requested clarification is attached.
If you require further information on this matter, we would be pleased to meet with your staff at their convenience.
Sery r ly yours, q /
~h L,
H. L. Stewart cc: Mr. James P. O'Reilly Regional Administrator Region II U. S. Nuclear Regulatory Commission Atlanta, Georgia 30303 Mr. M. B. Shymlock NRC Resident Inspector North Anna Power Station l$k kN O
P 1
RADIATION EXPOSURE AS A RESULT OF RERACKING NORTH ANNA POWER STATION UNIT NOS.1 AfD 2 The activities performed in and around the fuel building resulting in radiation exposure include, fuel handling (refueling), and filter changes and demineralizer changes in the spent fuel pool purification system.
Experience with other reracking has shown that the direct dose, due to additional spent fuel being stored in the fuel pool, increases very little if any.
There would therefore, be no increase in the dose from fuel handling activities. As more fuel is stored in the fuel pool, there is the possibility for additional radioactive crud from the fuel assemblies being introduced into the fuel pool water.
The fuel pool purification system is capable of removing the additional impurities from the water.
This could, however, result in the need to change the filters and demineralizer resins on a more frequent basis than they presently are changed. Demineralizer resins and filter changes have been performed on an average of once every year to 18 months.
The basis for the frequency upon which resin and filters are changed out is high differential pressure, or high radiation level.
It is, therefore, possible that one additional filter change and demineralizer resin change each year will be required as a result of increasing the amount of spent fuel stored in the pool.
A filter change results in approximately 300 mrem of personal exposure and a demineralizer resin change results in approximately 46 mrem of personal exposure.
Therefore, the reracking of the fuel pool may result in an additional annual increment of 346 mrem.
1 b
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n TABLE OF RADIATION EXPOSURE FOR RERACKING ACTIVITIES 2
NORTH ANNA POWER STATION UNIT NOS. 1 AND 2 Work Phase
- of Workers Dose Rate (mr) Hours Dose (mr)
Rack Removal /
7 5
160 5600 Instal 1ation-D1yers 1
50 80 4000 Fuel Shuffle 2
10 134 2680 Disposal of Racks 3
3 130 1170 Total:
13,450 mr 1
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4 1
1 1
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