ML16223A663
| ML16223A663 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 01/08/1988 |
| From: | Wiggins J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Harrison R PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| Shared Package | |
| ML16223A664 | List: |
| References | |
| NUDOCS 8801150198 | |
| Download: ML16223A663 (8) | |
See also: IR 05000443/1987024
Text
EGULAY
INFORMATION DISTRIBUTIAPSYSTEM
(RIDS)
ACCESSION NDR:SS02170117
DOC.DATE: 88/02/05 NOTARIZED: NO
DOCKET #
FACIL:50-269 Oconee Nuclear Station, Unit 1 Duke Power Co.
05000269
AUTH.NAME
AUTHOR AFFILIATION
NORTH. P.J.
Duke Power Co.
TUCKERH.B.
Duke Power Co.
RECIP.NAME
RECIPIENT AFFILIATION
SUBJECT: LER 87-012-0O:on 871203idiscovered exam frquency of reactor
coolant pump
flywheels exceeded requirement of Tech Spec 4.2.3.Caused by QA deficieny..Inservice insp plan revised.
W/880205 Itr.
DISTRIBUTION CODE: IE22D
COPIES RECEIVED:LTR
ENCL
SIZE
TITLE: 50.73 Licensee Event Report (LER), Incident Rpt, etc.
NOTES:AEOD/Orntein:1.cw
0500026?
RECIPIENT
COPIES
RECIPIENT
COPIES
ID CODE/NAME
LTTR ENCL
ID CODE/NAME
LTTR ENCL
PD2-3 L.
1
1
PD2-3 PD
1
1
PASTISH
1
1
INTERNAL:
ACRS MICHELSON
1
1
ACRS MOELLER
2
2
AEOD/DOA
1
1
AEOD/DSP/NAS
i
1
AEOD/DSP/ROAB
2
2
AEOD/DSP/TPAB
1
1
ARM/DCTS/DAS
1
1
DEDRO
i
1
NRR/DEST/ADS
1
0
NRR/DEST/CEB
1
1
NRR/DEST/ELB
1
1
NRR/DEST/ICSB
1
1
NRR/DEST/MEB
1
1
NRR/DEST/MTE
1
1
NRR/DEST/PSB
1
1
NRR/DEST/RSB
1
1
NRR/DESt/SGB
1
1
NRR/DLPG/HFB
1
1
NRR/DLPG/GAB
1
1
NRR/DOEA/EAB
1
1
NRR/DREP/RAB
1
1
NRR/DREP/RPB
2
2
1
1
NRR/PMAS/ILRB
1
1
R2
i
i
RES TELFORD,j
1
1
RES/DE/EIS
1
1
RES/DRPS DIR
1
1
RGN2
FILE
01
1
1
EXTERNAL: EGE:
GROH.M
5
5
FORD BLDG HOY,A
1
1
H ST LOBBY WARD
1
1
LPDR
1
1
NRC PDR
1
1
NSIC HARRISJ
1
1
NSIC MAYSG
I
i
NOTES:
1
1
TOTAL NUMBER OF COPIES REQUIRED: LTTR
47
ENCL
46
U.S. NUCLEAR REGULATORY COMMISSION
(9-83)
APPROVED OMB NO. 3150-0104
LICENSEE EVENT REPORT (LER)
EXPIRES: 831/615
FACILITY NAME (1)
DOCKET NUMBER (2)
PAGE(
Oconee Nuclear Station, Unit 1
10 5 0 0 0oj2 16 19 1 9F 0 6
TITLE(4) Technical Specification Violation Due To An Exceeded Inservice Inspection
Interval Resulting From A Quality Assurance Deficiency
EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
MONTH
DAY
YEAR
YEAR
SEQUENTIAL
MS
MONTH
DAY
YEAR
FACILITY NAMES
DOCKET NUMBERS)
Oconee Unit 2
5
10 1 0101217 10
__1
7
0
Oconee Unit 3
015 1
0 1 01218 17
THIS REPORT
SUBMITTED PURSUANT
THE REQUIREMENTS OF 10 CFR §: (Check one or more of the following) (11)
MODE ()
IN
20.402(b)
20.406(s)
L
0.73(a(2WO
73.71(h)
POWER
20.406(aHI()
50.3614)
50.734)W10
73.711c)
LEVEL
(10)
0
1
0
20.04a
()(11n
60.36(1)(2)
50.73(s)(2(II
OTHER ISPocify In Absoct
-
10..
j
below and In Text, NRC Form
.
.20.405(a()(11)
[X
50.731a)(2(1)
50.73(a(2((vilIH(A)
366A)
..... ....
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20.405(s)(1)(0
50.73(a02il1)
50.73(a(2)IO
LICENSEE CONTACT FOR THIS LER (12)
NAME
TELEPHONE NUMBER
AREA CODE
Philip J. North, Licensing
70l4 1317 131-
17 14 15 16
COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
MANUFAC-
R EPORTAB L EI;:>i:.~:
.
MANUFAC-
REPORTABLE
CAUSE
SYSTEM
COMPONENT
TURER
TO NPRDS
I:.::
- ..::::
CAUSE
SYSTEM
COMPONENT
TURER
TO NPRDS
.
SUPPLEMENTAL REPORT EXPECTED (14)
MONTH
DAY
YEAR
EXPECTED
SUJBMISSIGN
DATE (1S)
YES If res, comple EXPECTED SUBMISSION DATE)
NO
ABSTRACT (Limit to 1400 spec, i.e., approximerely fifteen single-ipece typewritren lineu/ (16)
On December 3, 1987 during a procedure implementation review it was discovered
that the examination frequency of the Reactor Coolant Pump (RCP) flywheels had
exceeded the requirements of Technical Specification 4.2.3.
This specification
states the frequency of inspection for the RCP flywheels to be approximately
three years.
Upon review of this incident, it was discovered that the required
frequency was violated four times involving all three units. During each
inspection, the unit being inspected was shutdown for refueling.
The root cause of this incident was determined to be a Quality Assurance
Deficiency because
QA-Operations interpreted that the required three year
inspection period allowed a time period of 3 to 5 years between inspections.
This exceeded the interval intended by Specification 4.2.3 and ASME Section XI.
The immediate corrective action was to report the violation to QA-Operations.
Subsequent corrective actions involved an evaluation of past inspection results
to ensure the RCP flywheel had been inspected within the requirements established
by Specification 4.2.3.
Planned corrective actions include preparation of a
Technical Specification interpretation and revision to Inservice Inspection
plans.
....
. ...
...
NR )Form A*
- u.8.P0-1966456-81/187
.. .. .. . ...
3..
.
U.S. NUCLEAR REGULATORY COMMISSION
LICENSEE EVNT REPORT (LER) TEXT CONTINUATION
APPROVED OMB NO. 3150-0104
EXPIRES: 8/31/85
FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR
SEQUENTIAL
- REVISION
NUMBER
- NUMBER
Oconee Nuclear Station, Unit 1
0 5 0 10 10 12 1619
81 7 -
0 1 2 -
010 0 1 2 OF 0 1 6
TEXT (If more space is required, use additional NRC Form 366A sl (17)
Background:
The Reactor Coolant Pump (RCP) flywheel is a large metal plate that is keyed to
the pump shaft.
The momentum produced by the flywheel extends the coastdown time
of the RCP following the trip of that pump. The coastdown time is 1 to 2
minutes. Extending.the coastdown time helps prevent exceeding core thermal
limits if an RCP were to trip while at 100% power. While at power, it is
possible for the RCP flywheel to fail and produce high-energy missiles. The most
credible failure of the flywheel comes from defects within the flywheel. This
issue was addressed in NRC Regulatory Guide 1.14.
This Regulatory Guide
established a program to inspect the RCP flywheel on an approximately 3 year
interval.
This inspection interval was outlined in Technical Specification 4.2
and was an original Technical Specification.
Sequence of Events:
August 1975
0
Regulatory Guide 1.14 was issued to Licensed Nuclear
Power Plants by the NRC.
January 1, 1976
o
The actual inspection interval was 3 years + 1 year to
coincide with planned outages.
0
QA-Operations misinterpreted the inspection interval for
RCP flywheel inspection to be 3 to 5 years between
inspections.
July, 1981
o
Oconee Unit 1 RCP flywheel inspection was performed.
0
62 months had elapsed since the last Unit 1 inspection.
o
This was the first violation of Specification 4.2.3.
Feb./March, 1986
o
Oconee Unit 1 RCP flywheel inspection was performed.
0
55 months had elapsed since the last Unit 1 inspection.
o
This was the second violation of Specification 4.2.3.
Sept./Oct., 1986
o
Oconee Unit 2 RCP flywheel inspection was performed.
0
53 months had elapsed since the last Unit 2 inspection.
o
This was the third violation of Specification 4.2.3.
February, 1987
o
Oconee Unit 3 RCP flywheel inspection was performed.
0
57 months had elapsed since the last Unit 3 inspection.
0
This was the fourth violation of Specification 4.2.3.
December 3, 1987
o
A QA Technical Services Representative discovered the
Technical Specification violation while performing a
procedure implementation review.
0
The QA Technical Services Representative informed
QA-Operations of the Technical Specification violation.
December 3-7
o
QA-Operations researched the past inspection intervals
to determine how many violations occurred.
o
QA-Operations verified the last inspection on each unit
was within the Technical Specification required
schedule.
o
QA-Operations re-verified that the last inspection on
each unit was valid.
NRIC FORM 366A
(9 83i
U.S. NUCLEAR REGULATORY COMMISSION
(98)LICENSEE
ERNT REPORT (LER) TEXT CONTINUATI N
APPROVED 0MB NO. 3150-0104
EXPIRES: 8/31/85
FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR
SEQUENTIAL
REVISION
NUMBER
UM
NUMBER
Oconee Nuclear Station, Unit 1
0 15
0 10 10 2 1 619 8 1 7
0-
011 2 -
00 0 1 3 OF 0
6
TEXT (if more space is required, use additional NRC Form 366A's) (17)
Description of Occurrence:
In August, 1975 the NRC issued Regulatory (Reg.) Guide 1.14 to the licensees of
light-water-cooled power reactors. This Guide outlined an inspection program for
the RCP flywheels in order to minimize the.potential for their failures. Reg.
Guide 1.14 stated that the inservice inspection interval for the flywheels should
be at approximately 3-year intervals, during the refueling or maintenance
shutdown outages coinciding with the inservice inspection schedule as required by
Section XI of the ASME Code. No guidance was given by the NRC as to which ASME
class that the flywheels should be assigned and therefore it was up to Duke Power
to interpret the inspection schedule. The issue of an RCP flywheel inspection
program was outlined in Oconee's original Technical Specifications and was a
reflection of the program discussed above (i.e., approximately 3-year intervals).
The original Technical Specification for RCP Flywheel inspection was incorporated
into Quality Assurance (QA)-Operations 10-year Inservice Inspection Plan. This
interpretation was made by one QA-Operations individual. QA-Operations was aware
of the Inservice Inspection Program established in Section XI of the ASME code,
however they established their inspection schedule based on the statement
"approximately 3-year intervals" included in Technical Specification 4.2. This
led to a misinterpretation of the flywheel inspection schedule by QA-Operations
because their interpretation of Specification 4.2 inspection period was 3 to 5
years.
Duke Power Company utilizes Inspection Program B in Section XI of the ASME code.
This inspection program breaks the life of the plant into four equal inspection
intervals of 10 years each. Each inspection interval is subdivided into three
parts called inspection periods.
The inspection periods are 3, 4, and 3 years
long.
Therefore, during the first ten years of plant life, there are three
inspections.
They are at the 3rd, 7th and 10th calendar years of plant service.
The 2nd, 3rd, and 4th inspection intervals are similar to the first.
The
inspection periods may be increased by 1 year to enable an inspection to coincide
with a plant outage.
Since QA-Operation's inspection plan did not fully conform to the guidelines
established in Technical Specification 4.2.3, some of the inspection intervals
scheduled were in violation of Technical Specification 4.2.3.
Over the 12 year period between January 1, 1976 and February 28, 1987, there were
eleven RCP flywheel inspections. . During each inspection, all 4 pumps on each of
the respective units were inspected. Of the 11 inspections, 4 were in violation
of Technical Specification 4.2, because they exceeded the inspection period
established in Specification 4.2.
The above violations are based on ASME Section
Section XI Paragraph IWB which provides for inspection intervals to be 3 years
plus 1 year to allow the inspection to coincide with planned outages.
On December 3, 1987 a QA Tech Services representative discovered the violations
while he was performing a procedure implementation review. This review had
nothing to do with Oconee's RCP flywheel inspection program. His discovery of
this incident was above what was expected of him. His immediate actions were to
(9 83)
U.S. NUCLEAR REGULATORY COMMISSION
LICENSEE EVE T REPORT (LER) TEXT CONTINUATION
APPROVED OMB NO. 3150-0104
EXPIRES: 8/31/85
FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR
SEQUENTIAL
- REVISION
NUMBER
- NUMBER
Oconee Nuclear Station, Unit 1
0 15
0 0 0 2 1 61 9 8 1 7
0 112
-
0 10 0 4 OF
0
6
TEXT (If more space is required, use additional NRC Form 366A's) (17)
contact QA-Operations and inform them of the violation.
Between December 3 and
December 7, 1987, QA-Operations researched past inspection intervals to determine
how many violations occurred.
In addition, QA-Operations reviewed their records
and ensured the last inspections of the RCP flywheels at Oconee were within the
requirements of Specification 4.2.3.
Cause of Occurrence:
The root cause of this incident was determined to be a Quality Assurance
Deficiency due to QA-Operations' misinterpretation of Specification 4.2.
Their
interpretation of the inspection period allowed a time period of 3 to 5 years,
which did not conform to the standards established by Technical Specification 4.2 or ASME Section XI Paragraph IWB.
The reason for their misinterpretation was that they interpreted "approximately
3-year intervals" in Specification 4.2 to coincide with other surveillance
programs already established. In this instance, they did not recognize the fact
that they were required to follow different guidelines. An interpretation of
"approximately 3 years" was requested of a NRC Region II Inspector. He referred
to ASME Code,Section XI, Part IWB.
This interpretation gave guidance for the
inspection interval to be 3 years + 1 year to allow the inspection to coincide
with planned outages.
Another reason for this misinterpretation was because the Operations' QA manual
required only one person to interpret and implement a change or addition to their
Inservice Inspection Plan. Therefore, only one person was involved with the
interpretation and scheduling of the frequency of RCP flywheel inspections.
.
There was no review of the Inspection Plan by another individual. This is
considered to be a QA deficiency because a program had not been established to
prevent a single interpretation/implementation of a change to the Inservice
Inspection Plan.
A review of incidents over the past three years revealed two incidents where
surveillance intervals were exceeded. However, both of the incidents were caused
by personnel errors.
Since this incident was caused by a Quality Assurance
Deficiency, it is considered nonrecurring but similar.
There was no equipment failure, thus this incident is not NPRDS reportable.
There was no release of radioactive materials, radiation exposure, of personnel
injuries as a result of this incident.
Corrective Actions:
The immediate corrective action was for the QA-Tech. Services representative to
inform QA-Operations of the Technical Specification violation.
Subsequent corrective actions were for:
0
QA-Operations to verify that the most recent inspection of all three
Oconee Units' RCP flywheels were within the time schedule of Section XI
of the ASME code;
(9 83)
W
U.S. NUCLEAR REGULATORY COMMISSION
(9-83)
LICENSEE EVENT REPORT (LER) TEXT CONTINUATION
APPROVED OMB NO. 3150-0104
EXPIRES: 8/31/85
FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR
SEQUENTIAL
REVISION
NUMBER
NUMBER
Oconee Nuclear Station, Unit 1
0 15 10
0 10 2 1 619
81 7 -
01
-
0 0 0
5 OF 0
6
TEXT //f more space is required, use additional NRC Form 366A's) (17)
o
QA-Operations to verify the results of the most recent RCP flywheels
inspections on all three units;
O
QA-Operations to review their records to find out how many times
Specification 4.2.3 was violated;
o
QA-Operations to implement, in their QA Inspection Manual a program to
ensure no fewer than three individuals review a change/addition to
their Inservice Inspection Plan. This was implemented in April, 1981.
Planned corrective actions are for:
o
The Compliance Section to draft a Technical Specification interpreta
tion for Specification 4.2.3 that will reflect ASME Section XI
Paragraph IWB.
o
QA-Operations to revise all three Oconee Inservice Inspection plans to
ensure the RCP flywheels are inspected every 3 years + one year to
coincide with planned outages.
Analysis of Occurrence:
The commitment to inspect the RCP flywheels was enhanced from recommendations of
NRC Regulatory Guide 1.14, "Reactor Coolant Pump Flywheel Integrity".
flywheel integrity needs to be maintained for two reasons:
1) to ensure that the
RCP remains operable for the sake of primary coolant flow, and 2) to ensure that
missiles cannot be generated from flywheel failure. RCP inoperability for
primary coolant flow concerns is fully analyzed in FSAR Chapter 15.6, "Loss of
Coolant Flow Accident" and shows that no fuel melting is predicted. However, the
consequences of flywheel-generated missiles are not analyzed in the FSAR as
stated in Chapter 3.5, "Missile Protection":
"Protection is not provided for certain types of missiles for which
postulated accidents are considered incredible because of the material
characteristics, inspections, quality control during fabrication and
conservative design as applied to the particular component. Included
in this category are missiles caused by massive, rapid failure of the
reactor vessel, steam generator, pressurizer, main coolant pump casings
and drives."
The position of the FSAR is consistent with that of Regulatory Guide 1.14 which
states, "If the flywheel .
.
.
is conservatively designed and made from suitable
materials with closely controlled quality, if adequate design review of new
configurations is provided, and if adequate inservice inspection is provided, the
probability of a flywheel failure is sufficiently small that the consequences of
failure need not be protected against."
FSAR Chapter 5.4.4, "Reactor Coolant Pump Motors," shows that the above
requirements of design conservatism and material/fabrication quality has been
satisfied. The largest amount of confidence in the flywheels is obtained from
(9 83)
US. NUCLEAR REGULATORY COMMISSION
(983)
LICENSEE EV NT REPORT (LER) TEXT CONTINUATION
APPROVED OMB NO. 3150-0104
EXPIRES: 8/31/85
FACILITY NAME (1)
DOCKET NUMBER (21
LER NUMBER (6)
PAGE (3)
YEAR
SEQUENTIAL
- REVISION
NUMBER
- NUMBER
Oconee Nuclear Station, Unit 1
0
5
0
0 0
2 6 9
8 7
0 1 2 -
0 0 6
OF
TEXT (If more space is required, use additional NRC Form 366A's) (171
the design conservatism. The flywheel design is based on design speed of 125
percent. Also, the flywheels are designed for 10,000 starts while the Duke Power
specification is for no more than 500 starts in forty years.
Calculations based
on the flywheel material show that 400,000 starts are needed before crack
initiation (a factor of 800 over the Duke Power specification).
The flywheel inspections occurred at 62 and 55 months from the previous
inspections for Unit 1, at 53 months for Unit 2, and at 57 months for Unit 3.
These intervals exceeded or failed to meet the Technical Specification 4.2.3
inspection requirement by 29% and 15% for Unit 1, 10% for Unit 2, and 19% for
Unit 3. The safety margins in the flywheel design and fabrication were adequate
to compensate for this increased time between inspections.
Furthermore,
subsequent inspections showed that the integrity of the flywheels had not
degraded during the time periods between inspections.
This fact along with the
large margin of conservatism in the flywheel design proves that safety was not
compromised and that the health and safety of the public were not affected by
this incident.
(9 83)
DuKE POWER COMPANY
P.O. BOX 33189 .
CHARLOTTE, N.C. 28242
HAL B. TUGKER
TELEPHONE
VICE PRESIDENT
(704) 373-4531
NUGLEAR PRODUCTION
February 5, 1988
U. S. Nuclear Regulatory Commission
Attention:
Document Control Desk
Washington, D. C. 20555
Subject:
Oconee Nuclear Station
Docket Nos. 50-269
Gentlemen:
Pursuant to 10 CFR 50.73 Sections (a) (1) and (d), attached is Licensee Event Report
(LER) 269/87-12 concerning a violation of Technical Specifications due to
exceeded reactor coolant pump flywheel surveillance intervals.
By letter dated
January 7, 1988 Duke informed the NRC of the delay in submitting this report.
This report is submitted in accordance with §50.73(a)(2)(i)(B).
This event is
considered to be of no significant with respect to the health and safety of-the
public.
Very truly yours,
Hal B. Tucker
PJN/1332/sbn
xc:
Dr. J. Nelson Grace
American Nuclear Insurers
Regional Administrator, Region II
c/o Dottie Sherman, ANI Library
U. S. Nuclear Regulatory Commission
The Exchange, Suite 245
101 Marietta Street, NW, Suite 2900
270 Farmington Avenue
Atlanta, Georgia 30323
Farmington, CT 06032
Ms. Helen Pastis
INPO Records Center
Office of Nuclear Reactor Regulation
Suite 1500
U. S. Nuclear Regulatory Commission
1100 Circle 75 Parkway
Washington, D. C. 20555
Atlanta, Georgia 30339
Mr. P. H. Skinner
M&M Nuclear Consultants
NRC Resident .Inspector
1221 Avenue of the Americas
Oconee Nuclear Station