ML20094G142
| ML20094G142 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 08/08/1984 |
| From: | Hukill H GENERAL PUBLIC UTILITIES CORP. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20094G143 | List: |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-3.D.3.4, TASK-TM 5211-84-2199, NUDOCS 8408130218 | |
| Download: ML20094G142 (2) | |
Text
. - - -
o
-p GPU Nuclear Corporation Nuclear
=,ome:r8o s
Middletown, Pennsylvania 17057-0191 717 944 7621 TELEX 84 2388 Writer's Direct Dial Nurnber:
August 8,1984 5211-84-2199 Office of Nuclear Reactor Regulation Attn:
J. F. Stolz, Chief Operating Reactor Branch No. 4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, DC 20555
Dear Mr. Stolz:
Three Mile Island Nuclear Station Unit 1, (THI-1)
Operating License No. DPR-50 Docket No. 50-289 Control Room Habitability (III.D.3.4., NUREG 0737)
In response to a previous commitment made during a telephone conversation of June 1,1984, GPU Nuclear Corporation (GPUN) has evaluated the consequences of off-site toxic chemical hazards on control room habitability using a Probabilistic Risk Assessment (PRA) approach. is a report prepared by Pickard, Lowe and Garrick, Inc., a consultant for GPUN, on this subject. This report is being submitted to you for your review.
The results of the report indicate that the aggregate of probabilities of exceedence of the toxic limit in the Control Room (CR) due to all chemical releases excluding that of chlorine, is 6.52x10-6 per year.
Attachments 2 and 3 tabulate the time required to reach the toxic limits and the frequency of exceedence of the toxic limit in the CR for each chemical respectively. GPUN has already comitted to install a chlorine monitoring system and hence the effects of chlorine release on overall aggregate probability is not included.
8408130218 e4ogog DRADOCK05000g h
GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation
/
Mr. J. F. Stolz 5211-84-2199 The results of the actual plant specific analysis indicated that the total offsite doses in excess of 10CFR100 limits is 3.3x10-lu} which might lead to frequency of all scenarios (excluding that of chlorine per year.
(NOTE:
Probability of off site release in excess of 10CFR100 = Probability of tank car accident leading to major release x Probability of exceeding TLY in Control Room x Average number of tank car /yr x Probability that Control Room
- Operator cannot take proper action to prevent core melt x probability of large release from the containment) which is well below the guidelines of the Standard Review Plan 2.2.3.
For other uilities the NRC Staff has accepted a conservative factor of 0.1 that could be applied to the probability to include the effects of operator incapacitation events that in itself would result in exposures in excess of e
-10CFR100 guidelines. Using even this c exceeding 10CFR100limitsis6.52x1010gnservativevalue,theprobabilityof per year which is stil.1 below the probability objectives stated in SRP 2.2.3.
We conclude from this analysis that transportation of off-site chemicals in the vicinity of TMI-1 do not pose an undue threat to the control room operator, that the probability of off-site radiation dores exceeding the 10CFR100 guidelines is less than 10-6, and that no toxic gas monitors
- (except for chlorine) are necessary.
Sincerely,
. D. Hukill Director - TMI-1 MI: dis:vjf Attachments e
0049A
___