ML20216B529

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Discusses Insp Rept 50-341/97-11 on 970804-1010 & Forwards Nov.Violations Re Change to EECW Sys That Appeared to Represent Usq.Predecisional Enforcement Conference Was Held on 971118.List of Attendees & Slides at Conference Encl
ML20216B529
Person / Time
Site: Fermi DTE Energy icon.png
Issue date: 03/04/1998
From: Grobe J
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To: Gipson D
DETROIT EDISON CO.
Shared Package
ML20216B533 List:
References
50-341-97-11, EA-97-479, NUDOCS 9803130111
Download: ML20216B529 (4)


See also: IR 05000341/1997011

Text

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March 4, 1998

EA 97-479

,

Mr. D. R. Gipson

.

Senior Vice President

Nuclear Generation

Fermi 2 Nuclear Power Plant

The Detroit Edison Company

6400 North Dixie Highway

Newport, MI 48166

SUBJECT: , NRC PRE-DECISIONAL ENFORCEMENT CONFERENCE SUMMARY AND

NOTICE OF VIOLATION (INSPECTION REPORT NO. 50-341/97011(DRS))

Dear Mr. Gipson:

This refers to an inspection conducted from August 4,1997 through October 10,1997 at the

Enrico Fermi 2 Nuclear Power Plant (Fermi 2). An apparent violation, involving a change to the

emergency equipment cooling water (EECW) system that appeared to represent an unreviewed

safety question (USQ), was identified during this inspection. The exit meeting for this

- inspection was conducted on October 10,1997. The inspection report was mailed to Fermi 2

by letter dated October 29,1997. On November 18,1997, a predecisional enforcement

conference (PEC) was held in the NRC Region Ill office to discuss the apparent violation. The

attendance list and the slides used during your portion of the conference presentation are

enclosed with this letter.

Based on the information developed during the inspection and the information provided by

representatives of Fermi 2 at the PEC, the NRC has determined that a violation of NRC

requirements occurred. This violation involves the failure to perform an adequate safety

evaluation, such that it was not readily apparent that an USQ did not exist. During and after the

conference, members of the Fermi 2 staff presented additional information as to why an USQ

did not exist.

The issue involved a 1995 safety evaluation for a modification to the plant to allow use of the i

safety-related EECW system to supplement the non-safety-related reactor building closed

cooling water (RBCCW) system during normal operation. This operational modification was

primarily to ensure adequate drywell cooling during hot weather conditions. Prior to that time,

EECW would be automatically initiated on: (1) high drywell pressure, (2) loss of offsite power,

and (3) loss of RBCCW. Although manualinitiation was available, it was not used during

normal operation, other than for testing purposes. Initiation of EECW, either by automatic or Il ,

I '

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J manual means, would isolate several non-ssfety-related loads, especially control rod drive 1

motor cooling. In order to use the EECW to augment RBCCW, operators would be required to i

restore these non-safety-related loads following manual initiation. When the safety evaluation j

was first approved, the Fermi 2 engineering staff assumed that any accidents would result in l

automatic initiation of EECW, along with re-isolation of the non-safety-related loads.

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D. R. Gipson 2 March 4, 1998

In 1996, the NRR Project Manger identified the potential for an accident scenario outside

containment which would not re-isolate the non-safety-related loads. In following up on this

concem, engineering personnel performed a worst-case computer analysis and determined

that, during a high energy line break and without a concurrent loss of offsite power, some

components cooled by EECW apparently would not reosive adequate flow to handle their

design-basis heat load. To rectify this condition, the engineers determined that operator action

to rainitiate EECW following a high energy line break was necessary. The safety evaluation

was revised accordingly.

During review of the revised safety evaluation, the inspectors questioned whether a new EECW

failure mode had been introduced. The change to the facility to permit augmentation of

RBCCW normal loads by the EECW system potentially introduced an USQ because there was

now a possibility of a malfunction of a safety-related system that was different than that

evaluated in the safety an.Jysis report. It appeared that, when EECW augmented RBCCW, a

loss of RBCCW would not automatically start EECW and the non-safety-loads would not be

isolated, depriving the essentialloads of adequate cooling. This scenario was not previously

evaluated.

During the PEC, members of the Fermi 2 staff presented the results of additional analyses

which showed that the operator actions were not actually necessary following a high energy line  ;

break. Based on this more realistic modeling of the post-accident heat sources, the staff was j

able to confirm that the safety related loads would still have received adequate cooling, even if i

the operators had not taken the procedurally required actions. Although this end result was

fortunate, the NRC is concemed that the Fermi 2 staff did not recognize that the Interim safety

evaluation, which concluded that operator action was necessary to ensure adequate cooling to

safety-related loads, posed an apparent USQ, based upon procedural guidance, and did not

take steps to resolve that discrepancy. The NRC depends on a licensee performing an

adequate safety analyses to determine whether or not an USQ exists. A licensee's safety

analysis for the existence of an USQ is fundamental to ensuring the bases on which the plant

was licensed are maintained. NRC determined that a major factor leading to the inadequate

analysis was an engineering mind set that use of operator actions was acceptable. Therefore,

the initial Fermi 2 analyses were done to show that sufficient time existed for the operator to

take action under an extreme set of heat load conditions, rather than to evaluate whether ,

operator actions were truly necessary. Once NRC questioned this premise, the Fermi 2 i

engineers identified the conservatism in the analyses, and, based on engineering judgement of I

the extent of the conservatisms, determined that sufficient flow would be available for

equipment cooling. This engineering judgement was then promptly confirmed through

computer analyses.

Therefore, after consultation with the Director, Office of Enforcement and in accordance with

the " General Statement of Policy and Procedures for NRC Enforcement Actions," NUREG-1600

(Enforcement Policy), the violation was categorized at Severity Level IV. This decision was

based on: 1) a detailed evaluation not being needed to resolve the matter; 2) the operator

actions not being necessary; and 3) given the time frame available, had the operators taken the

actions specified by the procedure, there was little likelihood of either operator error or adverse

consequences in taking the actions specified.

j

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D. R. Gipson 3 March 4, 1998

.

During the conference, members of the Fermi 2 staff identified immediate corrective actions

including: restricting use of the EECW system in the augmentation mode, communication of

the safety evaluation deficiencies to all preparers and a review of other safety evaluations as I

part of the overall 10 CFR 50.59 upgrade program. The staff members also noted that all

safety evaluations were being approved by an engineering manager to ensure overall quality.

Also discussed were efforts to upgrade the 10 CFR 50.59 process. These included a reduced

number of preparers; additional training, with an emphasis on licensing basis documents;

procedural upgrades; and updated search capabilities. Finally, the staff noted that Fermi 2 was

participating in the industry initiatives on 10 CFR 50.59, and were performing a validation of the

updated final safety analysis report to remove inconsistencies. These corrective actions appear I

acceptable. ,

i

You are required to respond to this letter and should follow the instructions specified in the

enclosed Notice when preparing your response. In your response, you should document the

specific actions taken and any additional actions you plan to prevent recurrence. Your

response may reference or include previous docketed correspondence, if the correspondence

adequately addresses the required response. After reviewing your response to this Notice,

including your proposed corrective actions and the results of future inspections, the NRC will  ;

determine whether further NRC enforcement action is necessary to ensure compliance with I

NRC regulatory requirements.

I

In accordance with 10 CFR 2.790 of the NRC's " Rules and Practice," a copy of this letter and its  :

enclosures will be placed in the NRC Public Document Room (PDR). To the extent possible, I

your response should not include any personal privacy, proprietary, or safeguards .nformation I

so that it can be placed in the PDR without redaction. l

l

Sincerely,

original signed by H. O. Christensen

g

John A. Grobe, Director

Division of Reactor Safety

Docket No. 50-341 1

License No. NPF-43

Enclosures: 1. Notice of Violation

2. List of Attendees at Predecisional Enforcement Confesace

3. Licensee Slides Presented at Predecisional Enforcement Conference

cc w/encis: N. Peterson, Supervisor of Compliance l

P. A. Marquardt, Corporate Legal Department

Richard Whale, Michigan Public

Service Commission

Michigan Department of Public Health

Monroe County, Emergency Management Division

See Attached Distribution

DOCUMENT NAME: G:\DRS\FER02278.DRS

To receive a copy of this document. Indicate in the box "C" = Copy w/o attach /enci"E" = Copy w/ attach! enc'"N" = No copy

OFFICE Rlll:DRS C Rill;DRE Rill:DRP A[ NRR/OE /Y Rill:RAO E Rlll:DRS h

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NAME Loug ed:sd J .

- k" OkVe"s w Ca _

n/ Grobe

DATE 2/23/98 2 / 2/I/98 3'y/98 2/.3 /98 / I/98

OFFICIAL RECORD COPY

(- .

.

D. R. Gipson 4 March 4, 1998

Distribution

Docket File w/encls Rlli PRR w/encls Rlli Enf. Coordinator w/encls

PUBLIC IE-01 w/encls SRI, Fermi w/encls TSS w/encls

LPM, NRR w/encls J. L. Caldwell, Rlll w/encls DOCDESK w/encls

DRP w/encls A. B. Beach, Rlli w/encls IEO w/encls

DRS w/encls J. Lieberman, OE w/encls J. Goldberg, OGC w/encls

B. Boger, NRR w/encls

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