ML19340A969
| ML19340A969 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 06/20/1975 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19340A966 | List: |
| References | |
| NUDOCS 8009100911 | |
| Download: ML19340A969 (3) | |
Text
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U'oelTf D STATES NUCLEAR REGULATORY ' OMMISSION C
W ASHINGTON. D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION 4
SUPPORTING AMENDMENT NOS.10 TO FACILITY OPERATING LICriN32S DPR-2 AND DPR-19 AND AMENDMENT NO. 9 TO FACILITY OPERATING LICENSE DPR-25 COMMONWEALTH EDISON COMPANY DOCKET NOS. 50-10, S0-237 AND 50-249 INTRODUCTION i
By application dated April 23, 197S, Commonwealth Edison Company (CE) requested amendments to License Nos. DPR-2, DPR-19 and DPR-25.
'Ihe amendments would authori:e CE to receive, possess and use sealed cesium 137 sources, each with a maximum activity of 12 curies.
The Dresden 1 amendment would include in the reactor license authority to receive, possess and use, antimony 122-124 sealed sources not to exceed I-i 1250 curies each, and a 6 curie americium 241 sealed source.
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7 DISCUSSION i
The purpose of the cesium 137 sources is to reconstitute the strength of an existing high level gamma calibration facility.
The facility is i
used to calibrate radiation monitoring equipment used at Dresden Units i
1, 2 and 3.
At present, the facility contains a cobalt 60 source, j
which has decayed in strength to a level where it has limited usefulness as a high level calibration source.
The calibration facility is presently licensed by the Nuclear Regulatory Commission (N7C) Byproduct Material i
License No. 12-05650-01. The proposed license.mendment would transfer the authori:ation for this facility from the s;parate b>yroduct material license to the reactor licenses.
The transf e to the reactor license is consistent with our current practice of including byproduct material used in connection with operation of the reactor in the reactor licenses.
The safety considerations associated with a sealed cobalt or cesium source in the calibration facility at Dresden are the potential for contamination if the source encapsulation opens, the adequacy of the shielding and the administrative control of its.use. These considerations are related to occupational safety.
Since these sources are shielded
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- within a restricted area on the readtor site, are sealed and in solid form', and are not subjected to prepsures or temperatures which have the potential to cause wide spread contamination, thero are no significant public safety considerations associated with the use of the cesium at g.
Dresden.
The occupational safety con,siderations are similar to those associated with cobalt 60.
The calibration facility shielding is expected, based on experience, to limit radiation exposures to below 2 mrem per hour. Routine health physics practices by the health physics staff are expected to acceptably limit occupational exposures to values well under the guidelines of 10 CFR Part 20.
However, since insufficient information has been provided to enable us to evaluate use of an unrestricted quantity of cesium 137, we are limiting the amount authorized in each license to the 21 curie quantity stated in the CE submittal, which amount was used in our evaluation as explained above.
CE has requested that the Dresden 1 license be amended to include authorization to receive, possess and use americium 241 and antimony 122-124 as sealed sources. The use of a singic americium 241 source at Dresden 1 containing up to six curies has previously been evaluated by the NRC staff and approved by Byproduct Material License No. 12-05650-01.
Since insufficient information has been provided to enable us to evaluate use of an unrestricted quantity of americium 241, we are limiting the l
amount authorized in the Dresden 1 reactor license to that amount presently authorized by the Byproduct Material License. CE has requested that the Dresden 1, 2 and 3 licenses be modified to contain identical conditions permitting the use of an unspecified number of antimony 122-124 sources with a limit of 1,250 curies per source.
Because the licensee has not provided sufficient information to enable us to evaluate the possession and use of an unrestricted total quantity of antimony, we have modified the licensee's request to continue in effect the total quantity limits specified in the existing Dresden 2 and Dresden 3 licenses. This li:ense modification does not increase any limits presently in effect.
For Dresden 1, it merely transfers the authority to use the licensed material from the existing byproduct material license to the Dresden 1 operating license.
This action is consistent with current Commission licensing practices and will not result in any change in the manner in which these sources are used or in the radiation safety practices er; ployed to assure that the health and safety of the public is protected.
CC:CLUSIGN We have concluded, based on the considerations discussed above, that:
(1) because the change does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the change does not involve a significant hazards consideration, (2) there is reasonable c'c;n *
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assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Comission's regulations and the issuance of this amendment will not be inimical to the cormon defense and security or to the health and safety of the public.
Date:
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