ML20127L985

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Special Insp Rept 50-416/84-54 on 841206-17.Violation Noted: Failure to Meet Certain FSAR Commitments to Reg Guide 1.63 Re Redundant over-current Protection of Containment Penetrations
ML20127L985
Person / Time
Site: Grand Gulf Entergy icon.png
Issue date: 01/29/1985
From: Crlenjak R, Panciera V
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20127L953 List:
References
RTR-REGGD-01.063, RTR-REGGD-1.063 50-416-84-54, NUDOCS 8507010030
Download: ML20127L985 (5)


See also: IR 05000416/1984054

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Report No.: 50-416/84-54

Licensee: . Mississippi' Power and Light Company

Jackson, MS 39205

Docket No.: 50-416 License No. : NPF-29

Facility Name: Grand Gulf 1

Inspection Conducted: December 6 - 17, 1984

Inspector: .H VmY ), _ '

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T<. V. Crldnjat f ' Da'tb Signed

Approved by:

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Vindsnt~W. P;inciira, ChTef */ Da/ th' Signed

Reactor Projects Section 2C

Division of Reactor Projects

SUMMARY

Scope: This special inspection was conducted to evaluate the circumstances which

resulted in the licensee not meeting certain Unit 1 FSAR commitments to Regula-

tory Guide 1.63.

Results: Of the areas inspected and the review of the licensee's documentation

addressing these commitments, one apparent violation was identified; (Failure to

meet applicable regulatory requirements as specified in the license application).

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REPORT DETAILS

1. Licensee Employees Contacted

J. E. Cross, General Manager

C. R. Hutchinson, Manager Plant Maintenance

M. J. Wright, Acting Manager Plant Operations

R. F. Rogers, General Manager Technical Assistant

L. F. Daughtery, Compliance Superintendent

J. L. Robertson, Operations Superintendent

W. A. Russel, Operations Assistant

J. D. Bailey, Compliance

V. Holmbert, Fire Project Coordinator

2. Exit Interview / Management Meeting

On December 17, 1984, representatives of MP&L met with the NRC, at MP&L's

request, in the NRC Regional Office in Atlanta, Georgia. The topic of

discussion was the scope of and resulting corrective actions from a recent

MP&L review that revealed a number of circuits penetrating containment that

did not meet the redundant over-current protection requirements of RG 1.63

and/or did not include circuit breakers being used for this purpose, in

Technical Specifications.

3. Inspection Activities

This special report has been issued to address those circumstances that

resulted in a number of containment penetrating circuits of Unit I not

meeting the licensee's FSAR commitments to Regulato ry Guide (RG) 1.63.

The NRC site and regional staff reviewed and evaluated the technical

aspects and circumstances surrounding this licensee identified

noncompliance and considers the corrective actions taken by MP&L to be

acceptable.

a. Description

During July / August 1984, in the course of the licensee's updating of

Unit 2 motor control center drawings to conform to Unit 1 changes made

since suspension of engineering work on Unit 2, a discrepancy in the

design was identified. The licensee found that motor operated valve

(MOV) space heater circuits penetrating containment did not have backup

over-current protection as did the other 120 volt power panel feeds.

This condition was brought to the attention of the Bechtel Unit 1

engineers. After a review, it was determined that the commitments in

the FSAR Q&R 040.5 were not met. MOV space heaters were not afforded

the protection of its associated FSAR Q&R category. A check was made

of 120V power feeds to containment, and it was discovered that Standby

- Liquid Control System (SLCS) heat tracing also was not provided with

backup over-current protection.

Because of these deficiencies, a review of power and control circuits

was conducted. This review consisted of qualitative examination of all

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power and control circuits (per the circuit and raceway schedule)

penetrating the containment to determine into which category they fell,

and if there were any other circuits that did not fall into one of the

five categories. The results of that review uncovered no other defi-

ciencies.

Due to the Unit I deficiencies identified, on August 14, 1984, MP&L

requested an addition of 10 circuit breakers to the Unit 1 Technical

Specifications (TSs). This request prompted NRR to question the

licensee's Unit 1 TS review program. NRR requested by letter

(August 18, 1984) that MP&L address the issue. In response to the NRC

request, MP&L submitted a letter (AECM-84/0433, September 10, 1984)

discussing the identification of the FSAR commitment deficiencies

associated with the MOV space heater circuits and with the SLCS heat

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tracing circuits. The letter stated that ... MP&L conducted a

complete review of all circuits penetrating the primary containment to

ensure compliance with RG 1.63 and FSAR. . . ." This submittal also

reported the licensee's corrective actions.

In late November 1984, Bechtel Unit 2 engineering personnel identified

another deficiency with regard to SLCS pump control circuits. Further

evaluation by Unit 1 personnel identified similar deficiencies with the

SLCS pump control circuit containment penetrations. Additionally,

deficiencies were found with the containment penetrations of the

reactor protection system (RPS) scram solenoid circuits. Specifically,

the SLCS pumps had 500 VA control power transformers (CPT) which did

not conform to Category b.(5) circuits described in FSAR Q&R 040.5 and

adequate backup protection was not provided for the scram solenoid

fuses, in that the distribution breaker was underrated at 50A.

The items were not discovered during the August review since that

review only consisted of a qualitative evaluation of the circuits to

place them into one of the five FSAR Q&R categories and not a review of

the protection coordination. (For the SLCS pumps, the CPT size is not

shown on the drawing with the containment penetration and the SLCS pump

circuits were incorrectly identified as Category b.(5)).

Based on these discoveries, MP&L decided that a detailed review would

be necessary to uncover any similar situations. Therefore, Bechtel was

directed to conduct a an indepth review of the circuit protection for

each scheduled circuit penetrating the containment; ensuring that each

circuit was properly categorized and that proper breaker / fuse coordina-

tion existed. That review was conducted from December 7-15, 1984.

The NRC was informed of these discoveries and the ongoing review on

December 7, 1984.

In addition to the findings associated with RG 1.63 commitments, the

licensee also identified 52 low voltage control circuit breakers, for

which credit was taken for penetration protection, which were not

included in Unit 1 TS.

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The results of the MP&L review were discussed with NRC Region II staff

in; a meeting held on December 17, 1984 and were documented in MP&L's

l December 18, 1984 submittal. The following is a listing of deficien-

cies identified in the subject' review:

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'(1) SkM/IRM Drive Units Backup protection is marginal and is not

enveloped by curves included in FSAR

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(2) DC Power Supply Feed Optical Isolator circuits contain only to

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Isolators a single level of penetration protection.

! (3) Horizontal Fuel Only a single level of penetration System

Transfer Control protection has been provided (CPT rated

Circuit higher than 150VA)

(4) Refueling Platform Only single level of penetration

Interlock Circuit protection has been provided.

! (5) 'Tip Drive Control Only a single level of penetration

protection has been provided.

(6) Plant Communication Only a single level of penetration

P. A. System has been provided

i (7) Various 52 breakers not listed in Plant TSs

f b. Safety Significance

! No deficiencies of commitments to the over-current protection provi-

sions of RG 1.63 were identified in 'the licensee's review of higher

! power conductor containment penetrations. Circuits in the category

' have the greatest potential for penetration damage given an uninter-

l rupted over-current condition. For instrumentation and control

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circuits, however, adequate backup over-current protection was lacking

in some instances. Such instances were confined to circuits with

relatively small diameter conductors (maximum of #12 AWG wire) and

, inherently low energy levels (low voltage controls and instrumentation

i systems). To assess the safety significance represented by these

L noncompliances, an analysis was performed by the licensee to determine

! the impact of a proposed penetration failure on containment leakage

under postulated. loss of coolant accident (LOCA) conditions. The

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analysis concluded that the effective fai. led penetration leakage rate

based on FSAR post - LOCA pressure profiles, when combined with

containment corrected Type A testing results, is less than the TS

allowable leakage rate limits of 0.75 La over any 24-hour period. This

analysis assumed the presence of a short circuit condition, and'a

random single failure disabling the primary over-current protection

device, coincident with a design basis LOCA.

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On the basis of this conservative treatment of a postulated penetration

failure, coincident with other design basis conditions, the licensee

concluded that the deficiencies did not represent a substantial safety

hazard.

This conclusion applies as well to those circuits whose associated

circuit breakers were not in Technical Specifications. They were all

low voltage control circuits with small diameter conductors (#12 AWG or

less). It should be noted that while the subject breakers were not

specifically listed in TSs most of these breakers are similar in type

to those found in circuits that are currently included in the TSs. Of

course, those breakers included in the TSs were periodically tested in

accordance with the associated surveillance procedures. The TSs

prescribe testing of representative samples for low voltage breakers to

demonstrate that breakers of a given type are operable and capable of

performing their intended function. In addition, approximately one-third

of such circuit breakers were selected for testing, and all tested

satisfactorily. Thus, there is confidence that the subject penetrations

were adequately protected.

c. Summary

Due to an independent, ongoing engineering design review effort on GGNS

Unit 2, discrepancies were identified by Bechtel Power Corporation in

the Unit 1 provisions for over-current protection of containment

penetrations. MP&L, upon assessing the initial findings, took immedi-

ate actions and elected to conduct an intensive review effort to

confirm that the plant's design in this area was proper and that safe

operations were not adversely impacted. The review did identi fy

certain instances where the plant design did not comply with commit-

ments to Regulatory Guide 1.63 and circuit breakers providing over-

current protective functions were not included in the plant's TSs.

Accordingly, the statement made in the MP&L letter of September 10,

1984, that a complete review of all circuits penetrating primary

containment had been conducted is considered both false and material,

and is therefore a violation (416/84-54-01).

Plant modifications were implemented and completed prior to the Unit i

restart on December 19, 1984.

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