ML20065G361
| ML20065G361 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 09/24/1982 |
| From: | Fay C WISCONSIN ELECTRIC POWER CO. |
| To: | Clark R, Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.B.2, TASK-TM TAC-47965, TAC-47966, NUDOCS 8210040119 | |
| Download: ML20065G361 (2) | |
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wisconsin Electnc eona couraur 231 W. MICHIGAN. P.o. BOX 2046. MILWAUKEE, WI 53201 September 24, 1982 Mr. H. R. Denton, Director Office of Nuclear Reactor Regulation U.S. NUCLEAR REGULATORY COMMISSION Washington, D.C.
20555 Attention:
Mr. R. A. Clark, Chief Operating Rear. tors Branch 3 Gentlemen:
DOCKET NOS. 50-266 AND 50-301 ADDITIONAL INFORMATION NUREG-0737 ITEM II.B.2, PLANT SHIELDING POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 In a letter to you dated July 20, 1982, Wisconsin Electric Power Company provided additional information and justification for the implementation schedule proposed for NUREG-0737, Item II.B.2, " Plant Shielding", and several l
other items.
Our latest implementation schedule had been provided with our I
On September 14, 1982 we received a telephone call from Mr. Clark requesting additional information regarding the interim mitigating measures taken while the analyses and plant modifications planned in response 4
to Item II.B.2 are being completed.
In response to your telephoned request, we explained that the following actions have been or, in the event of an accident, would be taken.
Several of the plant emergency response procedures have been revised to specify necessary precautions required before post-accident re-entry into the auxiliary building or facade.
These procedures require that an evaluation of the area radiation monitoring system readoucs and radiological hazards be completed prior to re-entry.
Appropriate radiation surveys of designated areas are required before these areas may be entered to accomplish accident mitigating activities.
Re-entries must be authorized by the Site Manager, Duty and Call Health Physics Supervisor, and the Duty Shift Supervisor and are to be accomplished under the direct supervision of health physics personnel.
Hence, although the shielding modifications are not yet completed, we are aware, based on the analyses, calcu-lations, and studies done to date, of the potential radiation problem areas.
Based on this knowledge and the evaluation of area radiation monitor readouts and radiation survey results, we would instruct personnel regarding radiation levels which they might encounter and how to minimize their stay times or pro-vide necessary temporary shielding so that applicable dose limits would not be exceeded.
These actions could also include, if necessary, ;;rior flushing of safety injection ::;u T-idual heat removal lines to further minimize radiation sources in the vicinity of required maintenance activities.
l 0 8210040119 820924 PDR ADOCK 05000266 P
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e Mr. H. R. Denton September 24, 1982 i
None of the areas which we have identified as requiring the addition of permanent shielding are locations which require continuous or frequent per-sonnel access. The safety related 480 volt motor control centers would require.
access only if breaker maintenance became necessary.
In that case temporary shielding, line flushing, or other means would be utilized to minimize expo-sures.
Periodic access to the C-59 control panel is only required for the operation of non-safety related auxiliary systems.
Temporary shielding and line flushing may also be used at this location to minimize exposure.
Our analysis of control room doses indicated a need to shield the con-trol room doors and windows based on a number of very conservative source term assumptions. While the current reanalysis will be completed in about one week, preliminary results indicate only a minor amount of shielding is required (on the order of 4" lead equivalent) to reduce the dose rate to control room person-nel during the early hours of the accident.
In the event of a major accident, operators will be instructed to avoid door and window areas to the extent prac-ticable.
This can be done without ady'rsely impacting their freedom to respond to the accident.
It is important to note that the requirement for additional shielding is predicated upon a source term resulting from gross core damage including sig-nificant core melting and significant core fission product inventory release in accordance with the assumptions specified by NUREG-0737.
Any postulated accident which resulted in core damage less than that assumed in these analyses would, of course, result in correspondingly lower dose rates in the plant areas.
The " standard" major LOCA, for example, would not require any additional shield-ing.
In fact, a partial core melt involving only a few assemblies would simi-larly not require additional shielding.
We believe that our procedural requirements for accurate radiation surveys prior to entry and our plans to utilize temporary shielding, and other measures to reduce localized high radiation areas as necessary, provide adequate mitigating factors to permit continued plant operation while the shielding installations we have discussed with you previously are being implemented.
Very truly yours,
[
C. W. Fay Assistan Vice President cc:
NRC Resident Inspecto'.
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