IR 05000324/1981008
| ML20004D197 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 04/28/1981 |
| From: | Dante Johnson, Julian C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20004D194 | List: |
| References | |
| 50-324-81-08, 50-324-81-8, 50-325-81-08, 50-325-81-8, NUDOCS 8106080569 | |
| Download: ML20004D197 (9) | |
Text
.
[ Waruq'o-UNITED STATES
+
!
NUCLEAR REGULATORY COMMISSION
' E REGION 11
$
e'f 101 MARIETTA ST., N.W., SUITE 3100 o,,
ATLANTA, GEORGIA 30303
_
'g'
'
O Report Nos.
50-324/81-08 and 50-325/81-08 Licensee: Carolina Power and Light Company 411 Fayetteville Street Raleigh, NC 27602 Facility Name: Brunswick Docket Nos. 50-324 and 50-325 License Nos. DPR-62 ar.d DPR-71 Inspection a: Brunswick site near Wilmington, North Carolina Inspector:
[-
~ E I, D. F. John %6n, Senior ReMdent Inspector Date Signed Approved by:
b.
Z.
M
.
-
C. Julian, Acting Section Chief, RRPI Division Date Signed SUMMARY Inspection on March 15, - April 15,1981 Areas Inspected This inspection involved 158 resident inspector hours on site in the areas of operational safety verification; review of operational events; review of periodic reports; followup on licensee events reports (LER's); plant tours; reactive inspection effort relative to results from repair, functional testing and adeauate reinstallation of hydraulic snubbers and pipe support hangers on safety-related systems.
.
Results l
!
Of the six areas inspected, no violations or deviations were identified.
'. '.
- I I
I l
l
,
l h\\h
.
.
.
.
DETAILS
,
1.
Persons Contacted Licensee Employees D. Allen, QA Supervisor A. Bishop, Engineering Supervisor G. Bishop, Project Engi.,c ir
.
J. Brown, Manager, Opei. ;1ons
- C. Dietz, General Manager, Brunswick J. Dimmette, Mechanical Maintenance Supervisor M. Hill, Maintenance Manager R. Morgan, Plant Operations Manager G. Oliver, E&RC Manager
- A. Padgett, Assistant to General Manager R. Pasteur, E&C Supervisor
- R. Poulk, Regulatory Specialist W. Triplett, Administrative Manager W. Tucker, Technical and Admininstrative Manager Other licensee employees contacted included technicians, operators and engineering staff personnel.
- Attended exit interview 2.
Exit Interview The inspection scope and findings were summarizsd on April 13, 1981, with those persons indicated in Paragraph 1 above. Meet,js were also held with senior fac ility management periodically during the course of this inspection to discuss the inspection scope and findings.
Licensee representatives acknowledgcd their understanding of the findings.
,
3.
Review of Plant Operations a.
The inspector reviewed plant operations through direct in.spections and
'
I observations throughout the reporting period. The following creas were inspected.
,_
j (1) Control Room (2) Diesel Generator Rooms t
(3)
Service Building l
(4) Reactor Building l
(5)
Radiation Control Points l
(6)
Site Perimeter l
l
. -.
- --
.
.
,
.
..,.-
.. -..
- - - -, - - _ - -. - -
.--
- - _.
.
.
_
.
b.
The following determinations were made:
--Monitoring instrumentation: The inspector verified that selected instruments were functional and demonstrated para-meters within Technical Specification limits.
--Valve positions. The inspector verified that selected valves were in the position or conoition required by Technical Specifications for the applicable plant mode. This verification was control board indication only.
.
--Radiation Controls. The inspector verified by observation, that control point procedures and posting requirements were being followed. The inspector identified no failures to properly post radiation and high radiation areas.
--Fluid leaks. No fluid leaks were observed which had not been identified by station personnel and for which corrective action had not been initiated, as necessary.
--Piping vibration. No excessive piping vibrations were observed and no adverse conditions were noted.
l
--Control room annunciators. Selected lit annunciators were discussed with control room operators to verify that the reasons for them were understood and cc rective action, if required, was being taken.
--By frequent observation throughout the inspection period, the inspector verified that control room manning requirements of 10 CFR 50.54(k) and the Technical Specifications were being met. In addition, the inspector observed shift
.
turnovers to verify that continuity of system status was maintained. The inspector periodically questioned shift personnel relative to their awareness of plant conditions.
--Technical Specifications.
Through log review and direct observations during tours, the inspector verified comp-1.iance with selected Technical Specification Limiting Conditions;
. ~ ~ ~
for Operation.
-
'
--Security. During the course of these inspections, observat' ions relative to protected and vital area security were made, including access controls, boundary integrity, search, escort, and badging. No notable conditions were identified.
No violations were identified in this area.
l l
_
-.
.. _..
.
_-
.., - _
__
_.
---
..
...
.
.
-
.
4.
Reportable Occurrences The below listed Licensee Event Reports (LER's) were reviewed to determined if the information provided met NRC reporting requirements.
The determi-nation included adequacy of event description and corrective action taken or planned, existence of potential generic problems and the relative safety significance of each event. Additional in plant reviews and discussions with plant personnel, as appropriate, were conducted for those reports indicated by an asterisk.
'
Unit 1 1-81-13 (3L)
Procedural inadequacy with regard to control rod withdrawal pattern.
1-81-16 (3L)
Inadvertent isolation of reactor level instruments resulted in a reactor trip.
1-81-18 (3L)
Reactor low water level switch would not actuate during surveillance testing.
1-81-22 (3L)
Main steam line differential pressure switch found out of calibration due to instrument drift.
1-81-24 (3L)
Containment atmosphere monitor unit CAC-1263 tripped.
1-81-25 (3L)
HPCI system declared inoperable due to failed steam line drain pot.
1-81-29 (3L)
Control rod 14-19 full out position indication inoperable.
l
~ 1-81-30 (3L)
ECCS reactor low pressure switch would not actuate during testing.
- 1-81-38 (3L)
Diesel generator No. 2 was declared inoperable due to
low starting air pressure.
- 1-81-31 (IT)
The RCIC turbine was tripped inadvertently du tol operator error.
.
-
~~
Unit 2 2-81-17 (3L)
Reactor level instrument N0170 inoperable due to a failed reference leg.
2-81-18 (3L)
Failure of the containment atmospheric hydrogen analyzer.
i i
__,
. _ _ _. _
_
_
_ _ _. _ _. _
_ _ _.
_
.-
_
...
_
.
.-
_
.
2-81-19 (3L)
RHR shutdown cooling supply valve could not be operated remotely from the RTGB.
2-81-23 (3L)
Primary containment atmospheric oxygen analyzer out of calibration.
2-81-27 (3L)
Reactor coolant conductivity exceeded Technical Specification limits during startup.
2-81-30 (3L)
Control rod 26-39 was fully withdrawn but full out
.
position could not be achieved.
2-81-31 (3L)
Instrumentation isolation valve F014J closed, isolating main steam line flow instruments.
2-81-33 (3L)
Diesel generatoi No. 4 was declared inoperable due to high jacket water temperature.
2-81-34 (3i.)
Failure to perform surveillance test requirements on RCIC system.
2-81-37 (3L)
Reactor low level switch found out of calibration due to instrument drift.
2-81-40 (3L)
Suppression pool level indicator found reading downscale.
- 2-81-41 (IT)
Functional test results of hydraulic snubbers. (See details paragraph 7.)
LER 1-8* -31 (IT)
.
During normal plant operation, a RCIC system turbine tripped annunciator was received in the control room.
Investigation determined that the RCIC turbine had tripped and could not be reset from the control room. The RCIC system was declared inoperable. At the time of this event, the HPCI system was undergoing maintenance and was unavailable for service.
-
This event occurred when an auxiliary operator, who was unaware of the i
ongoing plant conditions, performed an unauthorized mfchanical overspeed
trip test of the RCIC System turbine without the consent of'the. unit Control Operator. Technical Specifications require that the HPCI System remain operable when the RCIC System is unavailable for service. At the time of this event, the HPCI System was under clearance to allow required calibra-tion of HPCI components.
Upon the receipt of the " turbine tripped" alarm annunciator for the RCIC System, the Control Operator contacted the auxiliary operator who was at the time attempting to reset the trip signal.
The manual trip must be reset locally. After approximately 15 minutes, the trip signal was reset by a Senior Control Operator who was dispatched to the
__ _
_.
___.
._
_, - _
_. _. _,
_
..
__-
.
.
.
.-
_
~
RCIC turbine to assist in resetting the turbine. As a result of this event, the involved auxiliary operator has been disqualified from making routine surveillance in the Reactor Buildings of both units.
Following this event, all operations personnel were lectured on the import-ance of knowing current plant operating conditions and communcating to one another any changes in plant systems' operability that might affect the overall plant condition.
In addition, all plant operations personnel were instructed nct to conduct unauthorized testing on any plant system.
An auxiliary operator training program is currently being conducted 'at the Brunswick site by a former BSEP Shift Operating Supervisor. This program includes classroom time as well as plant walk-tnroughs and equipment operation.
This LER was reviewed by all operations personnel with emphasis on the need to obtain the permission of the Control Operator when performing plant evolutions.
The inspector had no further questions relative to this event.
LER 1-81-38 (3L)
During normal operation, a diesel No. 2 start air pressure low alarm annun-ciated in the control room. No. 2 diesel generator was declared inoperable.
An investigation revealed that the 480 volt breakers for both air compressors for diesel generator No. 2 were in the "Off" position.
Both breakers were immediately placed in the "On" position and the air pressure was automatically restored to normal.
A subsequent investigation was conducted in an attempt to determine how and when the breakers were de-energized. This investigation included a review of periodic tests performed on the system, work authorization completed on the system or in the general work area, and general construction work that may have been in progress in the area.
The investigation could not determine a cause for this event.
,
The inspector had no further questions relative to this event;
':N 5.
Operational Events
'
During the period of this report, a follow-up on plant transients was conducted to determine the causes; ensure that safety systems and components functioned as required; corrective actions were adequate; and the plant was maintained in a safe condition.
Unit 1 At 2155 hours0.0249 days <br />0.599 hours <br />0.00356 weeks <br />8.199775e-4 months <br /> on March 29, 1981, with the plant operating at 96.5% power,
-,,
,~,
-
,,--.,,
,
-
-
m--, -
.
7
_
'
auto scram annun W tors A and B came on, also a low level trip annunciator alarm. A group one isolation occurred with reactor pressure at approxi-mately 960 lbs. RCIC was manually started and the diesel generators started automatically. APRM's A, C, E, & F received an upscale trip.
The cause of the reactor trip was later identified as a high flux scram due to a pressure spike that resulted from the closure of one of the MSIV's.
Subsequent investigation revealed that one of the MSIV discs on the C main steam line had separated from its stem and dropped into the line, sh.utting off steam flow.
The plant was returned to service on April 7,1981, with both MSIV's on the C line shut.
Reduced power operation with three main steam lines operable will continue until April 17, 1981, at which time the unit will be shut down for a scheduled maintenance outage and repairs cade to the affected MSIV.
The inspector had no further questions in this area.
6.
Review of Periodic Reports The inspector reviewed the following Licensee Reports.
--Brunswick Steam Electric Plant, Unit Nos.1 and 2 Monthly Operations Report for February,1981.
--Brunswick Steam Electric Plant, Unit Nos. I and 2 Annual Report.
l The inspector verified that the information reported by the licensee is j
technically adequate and satisfies applicable reporting requirements estab-
-
11shed in 10 CFR 50.
l The inspector had no further questions in this area.
No violations were identified.
7.
Inspection, Testing and Repair of Hydraulic Snubbers and Pipe Hangers on Safety-Related Systems
,
a.
While performing the functional test on the Unit No. 2 snubbers, a failure rate of 21 out of 101 was being realized on March 4,1981.
After an evaluation of this failure rate and the modes of failure, the plant was shut down.
Continued inspection of these snubbers has resulted in a total of 69 failuresout of 406 inspected as of March 16, 1981.
.
When the magnitude of the problem was identified, the manufacturdr was
!
requested to provide technical personnel on site to assist plant
!
personnel in establishing a comprehensive program for both determining
!
and correcting the causes identified. This vendor support was provided and a program was established to identify the causes of all identified l
l l
_ -
. - --
,
.
__
-,
.
e
-
failures and the required corrective actions. The major cause for the snubber failures appear to be due to system line vibrations which creates two modes of failure; (1)
Lino vibrations or a water hammer event can eventually lead to the poppet spring becoming lodged between the poppet and the poppet seat preventing the poppet from seating and preventing the snubber
.
from locking up.
(2)
Line vibrations can cause the poppet to vibrate against it.s seat guide, thereby causing the poppet surface bleed control veins to become worn, allowing the poppet to seat too securely and pre-venting the snubber from meeting its bleed rate specifications.
These system vibration related problems appear to be dependent on the length of the unit's operation, the number of unit startup/ shutdown cycles, and the amount of operation seen by each system. As a result of the number of failures and the apparent cause, all snubbers on Unit No. 2 will be inspected prior to the unit's return to power.
b.
A confirmation of action letter was issued to Carolina Power and Light Company from the NRC's Region II Atlanta Office on March 6,1981, stating the following:
(1) Complete the functional testing of all Technical Specification related snubbers outside the drywell and take corrective action, as necessary, to return defective snubbers to operable condition.
(2) Test additional Technical Specification related snubbers inside the drywell such that, combined with those previously tested in December 1980, 10% of the snubbers inside the drywell are func-tionally tested satisfactorily in acccedance with NRC require-ments.
.
(3) Establish a program which will determine the causes of the identified failures.
This program will also~ determine the short and long term corrective actions, as appropriate, to prevent recurrence.
.
(4) The plant Nuclear Safety Committee will frEquentl
' review the results of Unit 2 snubber testing to assure that-those.results do not adversely affect the continued operability of Unit 1 safety systems.
c.
In addition, a confirmation of concurrence letter was sent to Carolina Power and Light Company from the NRC's Region II Atlanta Office on
,.
__ -.
.-
. - _.
..
,
- - -
-. _.. --
... -
. -
. -
.
.
.-
P
-.
~
April 3, 1981, to include additional actions to be taken prior to the restart of Brunswick Unit 2.
These actions are stated below:
(1) A 100% inspection will be completed, by personnel independent of those performing the work, of the reinstalled hydraulic snubbers to verify proper reinstallation after functional testing and repairs.
(2) The inspection findings will be evaluated and any identified deficiencies resolved.
.
The resident inspectors were kept fully informed of the licensee's progress on the above items by direct observation in the field; review of applicable records; and daily contact with cognizant licensee personnel. The resident inspectors verified satisfactory completion of the above items associated with Brunswick Unit 2 on April 7,1981.
d.
On March 29,1981, Unit 1 tripped on high flux as a result of a closure of a MSIV (refer to details Paragraph 5 above).
An inspection of Unit 1 identified hydraulic snubber damage on an injection line on the HPCI system and pipe hanger damage on injection lines of the Core Spray System. As a result of the above, a 100% walk down and thorough inspection was initiated for all ECCS systems including RCIC and RHR systems.
.
e.
The NRC required that prior to the restart of Unit 1, the following
,
!
items be satisfactorily completed.
(1) Adequate repairs to the damage identified on the HPCI and CS systems.
i l
(2) Any and all discrept ncies identified as the result of the 100%
inspection of the F/CI, LPCI, CS, RCIC, RHR-and recirculation system piping be ad.quately resolved.
-
,
(3) An engineering evaluation be performed to determ'ine the cause of
failure of the pipe supports on the HPCI and CS. systems and corrective actierts to prevent recurrence.
.
,,
The resident inspectors verified completion of the above, items on.
April 7, 1981.
NRC Region II will review and further evaluate the results of the licensee's findings relative to Item (3) above.
l
,
.__
. _. - _ _ _ -. - -. -
-
.
-_
-.
--
_