ML19339B321
| ML19339B321 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 12/17/1976 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Groce R YANKEE ATOMIC ELECTRIC CO. |
| References | |
| NUDOCS 8011060738 | |
| Download: ML19339B321 (1) | |
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4 December 17, 1976 Yankee Atonic Electric Company Docket No. 50-29 Attention:
Mr. Robert H. Groce Licensing Engineer 20 Turnpike Road 1.'estborough, Massachusetts 01581
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Gen tlemen
- The enclosed Circular 76-07 is forwarded to you for action.
If there are any questions related to your understanding of the actions required, please contact this office.
.~r Sincerely, n.d.credD ames P. O'Reilly 7
D rector
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Enclosure:
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i Donald G. Allen, President l
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3-IE ::all 6 Files (For Appropriate Distribution)
, Cent ral I'iles Public Document Room (PDR)
Lccal Public Document Room (LPDR)
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- uclear Safety Information Center (NSIC)
Technical Information Center (TIC)
EEG:I Heading Room Cennonwealth of Massachusetts
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i IE Circular 76-07 Date:
December 17, 1976
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Page 1 of 3 h
INADEQUATE PERFORMANCE BY REACTOR OPERATING AND SUPPORT STAFF MEMBERS W
DESCRIPTION OF CIRCUMSTANCES
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O Increases in numbers of errors by members of the reactor operating and y
support staf f at various licensed power reactor facilities have resulted p
in a number of incidents where the individual's contribution to the g
overall " defense in depth" approach to safety was reduced.
3 A recent event of concern to NRC involved an inadvertent criticality at f
a boiling water reactor as follows:
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During refueling activities at a BWR an inadvertent reactor crit-l icality occurred due to operator error.
A shutdown margin test was f'
being conducted f rom the control room using an approved procedure.
This test calls for withdrawals of a high worth rod and a second rod diagenally opposite from the high worth rod.
The licensed hy reactor operator ir. correctly selected the adjacent control rod and L
withdrew it until the reactor was automatically scrammed by the reactor protection system.
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Other examoles of events of concern which represent a cross-section of such occurrences are listed below:
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Improper Reactivity Change / Power Distribution 1.
Valving error between refueling water storage tank and spent fuel i
pool lowered primary boron concentration.
i 2.
Incorrect estimated critical position and failur2 to recognize 1/M i
plot indications resulted in criticality being achieved with con-trol rods below the insertion limits.
r 3.
Leakage from secondary to primary side of steam generator through failed tubes resulted from improper maintenance which led to pri-mary system boron dilution.
4.
Personnel error and procedural inadequacies defeated an adminis-i trative control established to preclude inadvertent criticality i
resulting in the withdrawal of adjacent control rods.
3 5.
Improper control rod movements resulted in fuel cladding failures.
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Date:
December 17, 1976
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}L Improper Valve Linceps
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Valving errors led to overpressurization of the reactor coolant
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system.
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Valving error prevented two control rod hydraul'ic control units e
if-from being scrammed.
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Valving error resulted in air ejector offgas monitor being isolated.
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9.
Valving errors resulted in drywell atmosphere monitoring equipment f
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being isolated.
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.1 Improper Maintenance and Surveillance 4
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10.
Incorrect interpretation of a drawing resulted in a core boring 4
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penetrating a condensate storage tank (CST) level indicating line S
resulting in a loss of CST water and automatic realignment of ECCS g
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11.
Unauthorized offgas isolation valve wiring change resulted in an i
explosion, perst inel contamination, and injury.
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An operating error resulted in a diesel generator being returned to 2
P service in an inoperable condition.
I 13.
A calibration error resulted in the high power reactor trip set-points on all four power range channels being set in a non con-servative direction.
Although none of these events resulted in consequences af fecting the public health and safety, a review of these and other incidents indi-cates the operating or support staff member can be a significant con-tributor to such events.
Insufficient attention to and knowledge of plant operating history and status can degrade the individual's con-tribution to the overall defense in depth approach to nuclear safety.
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Recognition of the individual's role by both the operator and management e.
is a key elemsnt in the system for safe operation of nuclear reactors.
T Renewed emphasis is being requested to assure appropriate and continuing y
management attention to this important issue.
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3" Date:
December 17, 1976 N
Page 3 of 3 30 n T:
}H}p ACTION TO BE TAKEN BY LICENSEE:
hh Nucicar power reactor license conditions require that adequate proced-
- g ures be provided for the safe operation of the facility. To assure these yP procedures are being implemented, all operators of nuclear power reactor M
facilities with operating licenses are requested fo take the following j
action:
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Wu CONDUCT A REVIEW OF YOUR PLANS OR PROGRAMS WilICH ARE TO PROVIDE POSITIVE ASSURA"CE TilAT MEMBERS OF YOUR REACiOR OPERATING AND SUPPORT STAFF ARE, IN FACT,-COMPLYING WITl! THE SAFETY PROCEDURES YOU HAVE IN EFFECT AND THAT TilEY ARE AWARE OF SAFETY: RELATED INCIDENTS THAT HAVE OCCURRED AT YOUR FACILITY OR SIMILAR FACILITIES. Your review should include but not g
be limited to consideration of the following three matters:
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Program for. periodic shift and operator training whereby incidents g!
which occur.at your facility as well as at other licensed reactors, gy including all significant personnel errors, will be reviewed with j
the objective of identifying "the lessons to be learned."
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Procedures routinely implemented by knowledgeable individuals to j
qualitatively assess the performance of the operating and support staff in such.arcas as adherence to operating procedures, use of systems checklists, and implementation of component and system My -
tagouts.
This should include review of the degree to which operat-ing procedures, tagout procedures, and checklists require signof f, 1
1.c.,
signature or initials to verify proper completion and to N
identify the responsible personnel.
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Procedures for random backshift and weekend visits by management M
and supervision to the facilities, to-monitor and assess operations d
including crew manning and performance, equipment status and plant conditions.
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A report acknowledging coepletion of your review should be submitted
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within 90 days to the Director of the NRC Regional Office and a copy a
should be forwarded to the NRC Office of Inspection and Enforcement, Division of Reactor Inspection Programs, Washington, D.C.
20555.
<gy-Approval of NRC requirements for reports concerning possible generic problems has been obtained'under 44 U.S.C. 3152 from the U. S. General
.]y Accounting Office.
(CAO Approval B-180225 (R0072), expires 7/31/77.)
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