ML17195A758
| ML17195A758 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 04/24/1985 |
| From: | Zwolinski J Office of Nuclear Reactor Regulation |
| To: | Farrar D COMMONWEALTH EDISON CO. |
| References | |
| GL-83-28, LSO5-85-04-032, LSO5-85-4-32, NUDOCS 8504300473 | |
| Download: ML17195A758 (5) | |
Text
{{#Wiki_filter:Docket Nos. 50-237/249 LS05-85-04-032 Mr. Dennis L. Farrar Director of Nuclear Licensing Commonwealth Edison Company Post Office Box 767 Chicago, Illinois 60690
Dear Mr. Farrar:
April 24, 1985
SUBJECT:
SALEM ATWS ITEM 1.1 - REQUEST FOR ADDITIONAL INFORMATION Re: Dresden Nuclear Power Station, Units Nos. 2 and 3 By letter dated November 5, 1983, you responded to Generic Letter 83-28 with regard to req~ired actions based on generic implications of Salem ATWS events. The staff has reviewed your response to Item 1.1 (Post-Trip Review.and find~ that it does not fully meet the guidelines for this item in the following areas (se~ enclosure to this letter): C. The method and criteria for comparing the event with expected pl ant performance. *
- D.
The criteria for the need ~f independent assessment of the event following a trip. E. A systematic safety assessment program to assess unscheduled reactor trips. The guidelines for each of these areas and the required information are detailed in the enclosure. Ple~se respond within 60'days of receipt of this letter. This request for information was approved by the Office of Management and Budget under clearance number 3150-0011. Comments on burden and duplication may be directed to the Office of Management and Budget, Reports Management Room 3208, New Executive Office Building, Washington, D.C. 20503. riso43o0473 e5~424 ~ I
- PDR ADOCK 05000237 '.
I 1, P PD.R .LJ ; ~-
Enclosure:
Request for Additional Information cc w/enclosure: See next page DL:ORB#5 r* DL:~~ CJamerson:, RGilbert 1 !Jr /85 '-{I ~85 DL:O JZwolinski tj-h'f/85 Sincerely, .c ---~*- John A. Zwolinski, Chief Operating Reactors Branch Division of Licensin~ DISTRIBUTION Docket NRC PDR Local PDR OELD Jordan Partlow , CJamerson RGilbert -JZwol inski ABournia BGrimes ACRS (10) No.-.5 ~
Mr. Dennis L. Farrar cc Robert G. Fitzgibbons Jr. Isham, Lincoln & Beale Three First National Plaza Suite 5200 Chicago, Illinois 60602 Mr. Doug Scott Plant Superintendent Dresden Nuclear Power Station Rural Route #1 Morris, Illinois 60450 U. S. Nuclear Regulatory Commission Resident Inspectors Office Dresden Station Rura 1 Route #1 Morris, Illinois 60450 Chairman Board of Supervisors of Grun~y_ County Grundy tounty Courthouse
- Morris, Illinois 60450 U. S. Environmental Protection Agency Federal Activities Branch Region V Office ATTN:
Regional Radiation-Representative 230 South Dearborn Street Chicago, Illinois 60604 James G. Keppler, Regional Administrator Nuclear Regulatory Commission, Region III 799 Roosevelt Street Glen Ellyn,.Illinois.60137 Gary N. Wright, Manager Nuclear Facility Safety Illinois Department of Nuclear Safety 1035 Outer Park Drive, 5th Floor* Springfield, Illinois 62704 Apri 1 24, 1985
ENCLOSURE REQUEST FOR ADDITIONAL INFORMATION DRESDEN NUCLEAR POWER STATION, UNIT NOS. 2 AND 3 SALEM ATWS ITEM 1.1 - POST-TRIP REVIEW I. Review Guidelines The following review guidelines were developed after initial evaluation of various utility responses to Item 1.1 of Generic Letter 83-2S and incorporate the best features of these submittals. As such, these review guidelines in effect represent a "good practices" approach to post-trip review. The staff has reviewed the licensee's response to Item 1.1 against these guidelines: A. The licensee should have systematic safety assessment procedures established that will ensure that the following restart criteria are met before restart is authorized. 0 0 0 0 0 The post-trip review team has determined the root cause and sequence of events resulting in the plant trip. Near term corrective actions have been taken to remedy. the cause of the trip. The post-trip review team has performed an analysis and determined that the major safety systems responded to the event within specified limits of the primary ~ystem parameters. The post-trip review has not resulted in the discovery of a potential safety concern (e.g., the root cause of the event occurs with a frequency significantly larger than expected)., If any of the above restart criteria are not met, then an independent assessment of the event is performed by the Plant* Operations Review Committee (PORC), or another designated group with similar authority and experience. B. The responsibilities and authorities of the personnel who will perform the review and analysis should be *Well defined. 0 The post-trip review team leader should be a member of plant management at the shift supervisor level or above and should hold or should have held a Senior Operator license on the plant. The team leader should be charged with overall responsibility for directing the post-trip review, including data gathering and data assessment and he/she should have the necessary authority to obtain all personnel and data needed for the post-trip review.
0 0 A second person on the review team should be a Shift Technical Adviser (STA) or should hold a relevant engineering degree with special transient analysis training. A team leader and the STA (Engineer) should be responsible to concur on a decision/recommendation to restart the plant. A nonconcurrence from either of these persons should be sufficient to prevent restart until the trip has been reviewed by the Plant Operations Review Committee (PORC) or equivalent organization. C. The licensee should indicate that the plant response to the trip event will be evaluated and a determination made as to whether the plant response was within acceptable limits. The evaluation should include: 0 0 A verification of the proper operation of plant systems and equipment by comparison of the pertinent data during the post-trip review to the applicable data provided in the Final Safety Analysis Report (FSAR). An analysis of the sequence of events to verify the proper functioning of safety-related and other important equipment. Where possible, comparisons with previous similar events should be made. D. The licensee should have procedures to ensur~ that all physical evidence necessary for an independent assessment is preserved. E. Each licensee should provide in its submittal, copies of the plant procedures which contain the infonnation required in Items A through D. As a minimum, these should include the following: 0 0 0 0 The criteria for determining the acceptability of restart The qualifications, responsibilities and authorities of key personnel involved in the post-trip review process The methods and criterift for determining whether the plant variables and system responses were within the limits as described in the FSAR The criteria for detennining the need for an independent review
- II. Addition Information Required The-licensee in the November 5, 1983 letter provided information which was responsive to areas I.A. and I.B.
However, further information is needed ~o complete the staff's review in areas I.C., D., and E. as follows: C. The licensee has not addressed the methods and criteria for comparing the event information with known or expected plant behavior. The staff recommends that the pertinent data obtained during the post-trip review be compared to the applicable data provided in the FSAR to verify proper operation of the systems or equipment. Where possible, comparisons with previous similar events should be made. D. The licensee has not addressed the criteria for the need of independent assessment of an event. The staff recommends that if any of the review guidelines (as stated in Section I.A.) are not met, an independent assessment of the event should be performed by the PORC or a group with similar authority and experience. However, the licensee has established procedures to ensure that all physical evidence necessary for an independent assessment is preserved. E. The lic~nsee has not provided for the staff'~ review a. systematic safety assessment program to assess unscheduled reactor trips. The staff recommends that the licensee develop a systematic safety assessment program to handle unscheduled reactor trips.}}