ML20235J357

Forwards Status Rept for Period 870830-0912

ML20235J357
Person / Time
Site:	Davis Besse
Issue date:	09/25/1987
From:	Defayette R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:	Norelius C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
NUDOCS 8710010410
Download: ML20235J357 (4)

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[/N b USNRC-DS SEP 2 5 1987 l

lW1 SEP 30 A 9 il MEMORANDUM FOR: Charles E. Norelius, Director, Division of Reactor Projects '

THRU: W. G. Guldemond, Chief, Projects Branch 2 f FROM: R. W. DeFayette, Chief, Projects Section 28

SUBJECT:

DAVIS BESSE. STATUS REPORT FOR THE PERIOD AUGUST 30 THROUGH :I SEPTEMBER 12, 1987 1

Enclosed is the first Dav'is Besse bi-weekly Status Report. During this period site coverage was provided by the resident inspectors, augmented with a region "]

r based inspector along with an Augmented Investigation Team (AIT) which was onsite during the week of September 8,- 1987. ,

This Status Report is intended to provide NRC management'and the public with an overview of plant activities and NRC inspections. Subsequent inspection ~ .

reports will address many of these topics in more detail. 1 1

" Original signed by R. W. DeFayette" R. W. DeFayette, Chief Reactor Projects Section 2B

Enclosure:

Davis Besse bi-weekly 1 Status Report cc w/ enclosure:

L. Storz, Plant Manager DCD/DCB (RIDS) )

Licensing Fee Management Branch Resident Inspector, RIII Harold W. Kohn, Ohio EPA James W. Harris, State of Ohio '

Robert M. Quillin, Ohio  :

Department of Health State of.0hio, Public.

Utilities Commission 1 Ok 6 RI RI k

De ayette/cs G nd 9/kJ/87 9 /87

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i ENCLOSURE 4 Davis Besse Status Report August 30 through September 12, 1987

1. Plant Status During the first week of this reporting period the; plant operated at 100

-percent power. 'During the second week the plant was shut down~due to a j

l reactor scram on September 6 followed by'several equipment problems.

2. Facility Operations Summary (A) A brief summaryo ' f this years operating history is being provided to help maintain an up-to-date cognizance of plant conditions. t indicators, and events of regulatory interest. . As of August 31 the plant has operated at an availability factor 'of'80.5 percent with a major portion of the down time attributed to a planned maintenance . j outage. There have been 4 reactor scrams to date',- (two of which were caused by equipment failure, one caused by severe lightning strikes-and one caused by a construction worker bumping an electrical control y switch); 7 engineered safety features actuations; 71 limiting.

conditions for operations;~ 710 CFR 50.72 reports and 2 Technical ]

Specification violations. A planned 30 day maintenance shutdown-  ;

began on May 8 and continued until June 14. The following are the 3 more significant outage activities performed during this outage. ]'

(1) Replaced pressurizer code safety valves (2) Replaced valve RC-11 (Pressurizer relief isolation valve)

(3) Repaired motor driven feed pump l (4) Replaced the power operated relief valve-(5) Repaired core flood check valve (6) Replaced all four reactor coolant pump seals  !

1 (7) Repaired all six turbine bypass valves 1

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(8). Repaired or replaced packing on 35 manual reactor coolant system -l valves a y

(9) Replaced bearing on auxiliary feed pump number 2 i (B) The facility operated at 100 percent power during the first.8 days of this 14 day reporting period. On September 6 the unit scrammed-  ;

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'due to a failed feedwater flow transmitter. The failed' flow transmitter caused the integrated control system to increase feedwater flow to one steam generator.. This increased flow caused a ,

decrease in the reactor coolant system temperature which increased

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1 the reactivity. and caused a reactor scram due to high flux. During. "

the trip recovery and cooldown several problems occurred which are s currently under investigation by the licensee and a NRC Augmented i Investigation Team (AIT). (

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3. Items of Special Interest Additional Equipment Failures During the Event on September 6 i 1

1 (A) After the reactor scram on September 6,1987 an electrical breaker  !

' failed to transfer electrical loads from the station transformer to a startup transformer resulting in the automatic starting.of an emergency diesel generator. Also lost because of this nontransfer.

was non-vital bus "A" resulting in the loss of two reactor coolant pumps', but the remaining two reactor coolant pumps were unaffected and continued to operate. Service water pump #1 failed to auto restart after the loss of power; however, the pump was started from i the control room.

Another malfunction was the failure of a main steam safety relief valve to reseat on the Number 1 steam generator. While in mode 3 and cooling down an automatic start of the auxiliary feedwater (AFW) ,

system occured because of a low level in steam generator Number 2. 1 The low level was caused by a turbine bypass valve failing open. The 4 AFW pump returned the level to normal and.the AFW system was placed in standby.

During this event the licensee made the proper notification _to NRC Headquarters, Region III and the resident inspectors. The senior i

resident inspector monitored the status of the plant throughout the  !

event, and responded to the site over the Labor Day weekend.

(B) On' September 8, an Augmented Investigation Team (AIT), led.by a  ;

Region III-senior manager and supported-by NRC Headquarters  :

personnel, was dispatched to the site. The AIT began evaluating the event, interviewing operators, reviewing the licensee's' root cause determinations, and witnessing troubleshooting and. testing. On September 11 the AIT concluded its on-site activities. The preliminary results indicate that (1) The plant did not exceed any Technical Specifications or design limits w_ . _ _ _ _ _ _ - _

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during the event, (2) the existing emergency procedures are-adequate,'(3) the. licensee's special management team is conducting a

thorough and. vigorous investigation and (4)Lthe licensee is taking corrective action on the equipment which malfunctioned during the event and inspecting similar equipment which did not fail. As a follow up. inspection the resident inspectors reviewed.the status of.

maintenance on~several systems- Six systems were selected at random:

and an examination of. outstanding maintenance requests was made by the inspectors-who walked down the systems. . The inspectors. concluded that the maintenance backlog for the systemsLinspected should not

. affect the continued ability of:the systems to perform their functions.and that the backlog . records ' accurately reflect the condition of:the systems examined.

I A management meeting was conducted between the NRC staff and the licensee on September 15,1987 in Bethesda, Maryland to discuss issues relating to the startup of the plant,'and results of the licensee's review of the reactor scram.

4. Changes to Period of Status Reporting This is the first of the bi-weekly status reports :for Davis Besse.

5. NRC Staff Activities during the Period During the first week of this reporting period the resident inspector-staff was augmented with a regional inspector. During the second week

( the AIT was also on site.

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