Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
January 4, 1991
TO: ALL HOLDERS OF OPERATING LICENSES OR CONSTRUCTION PERMITS FOR
NUCLEAR POWER REACTORS
SUBJECT: REMOVAL OF THE SCHEDULE FOR THE WITHDRAWAL OF REACTOR VESSEL
MATERIAL SPECIMENS FROM TECHNICAL SPECIFICATIONS (Generic Letter
91-01)
Technical specifications (TS) include limiting conditions for operation that
establish pressure and temperature limits for the reactor coolant system.
The limits are defined by TS figures that provide an acceptable range of
operating temperatures and pressures for heatup, cooldown, criticality, and
inservice leak and hydrostatic testing. These limits are generally valid
for a specified number of effective full-power years. A program for reactor
vessel material surveillance ensures the availability of data to update the
inservice operating temperature and pressure limits. This program will
assist in fulfilling the requirements of Appendix H to Part 50 of Title 10
of the Code of Federal Regulations (10 CFR) to prevent brittle fracture of
the reactor vessel.
The surveillance requirements associated with these limits specify the
withdrawal schedule for the reactor vessel material specimens. Recently,
the staff of the U.S. Nuclear Regulatory Commission (NRC) approved a request
to remove this schedule from the TS for the Joseph M. Farley Nuclear Plant.
This TS change was requested because Section II.B.3 of Appendix H to 10 CFR
Part 50 requires the submittal to, and approval by, the NRC of a proposed
withdrawal schedule for material specimens before implementation. Hence,
the placement of this schedule in the TS duplicates the controls on changes
to this schedule that have been established by Appendix H. Therefore, the
staff concluded that, because this duplication is unnecessary, the removal
of this TS schedule as a line-item improvement is consistent with the
Commission Policy Statement on TS Improvements.
The enclosed guidance addresses the preparation of a request for a license
amendment for this TS change. Licensees and applicants that plan to adopt
this line-item TS improvement are encouraged to propose changes to their TS
that are consistent with the guidance in the Enclosure. The NRC project
manager for the facility will review these amendment requests. Please
contact the project manager or the contact identified below if you have
questions on this matter.
This letter does not require any licensee to propose changes to its plant
TS. Action taken in response to the guidance provided in this generic
letter
9012310078
.
Generic Letter 91-01 - 2 - January 4, 1991
is voluntary and is not a backfit under 10 CFR 50.109. Therefore, Office of
Management and Budget clearance is not required.
Sincerely,
James G. Partlow
Associate Director for Projects
Office of Nuclear Reactor Regulation
Enclosure:
As stated
Contact: Tom Dunning, OTSB/NRR
(301) 492-1189
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Generic Letter 91-01 Enclosure
GUIDANCE FOR THE REMOVAL OF THE WITHDRAWAL SCHEDULE FOR
REACTOR VESSEL MATERIAL SPECIMENS FROM TECHNICAL SPECIFICATIONS
Introduction:
This enclosure provides guidance for the preparation of a request for a
license amendment to remove from the technical specifications (TS) the
schedule for the withdrawal of reactor vessel material surveillance
specimens. The control of changes to this schedule by way of a license
amendment to modify the TS duplicates the requirements of Section II.B.3 of
Appendix H to Part 50 of Title 10 of the Code of Federal Regulations (10
CFR). These requirements address the submittal of a proposed withdrawal
schedule, as specified in 10 CFR 50.4, and NRC approval before its
implementation.
Discussion:
The limiting conditions for operation (LCO) for the reactor coolant system
include operating limits on pressure and temperature that are defined in
figures that provide an acceptable region for operation during heatup,
cooldown, criticality, and inservice leak and hydrostatic testing. An
associated surveillance requirement addresses the frequency of verifying
that operation is within the specified limits during these operating
conditions. In addition, a separate surveillance includes the requirement
that reactor vessel material surveillance specimens be removed and examined
to determine changes in material properties, as required by 10 CFR Part 50,
Appendix H, and in accordance with the schedule in the referenced TS table.
The reference to this table along with the TS table providing the schedule
for the withdrawal of reactor vessel material surveillance specimens may be
removed from this surveillance requirement. This surveillance requirement
may also specify that the results of these examinations shall be used to
update the TS figures for the pressure and temperature operating limits. If
this requirement exists, it shall be retained.
The Bases Section for this TS provides a detailed description of the bases
for this LCO and the associated surveillance requirements. The standard
technical specifications (STS) bases reference the TS table that provides
the schedule for surveillance specimen withdrawal. The bases states that
the heatup and cooldown curves are recalculated when data from the
surveillance specimens indicate a change in material properties that exceeds
the limiting value of those properties that were used to develop the
existing pressure and temperature limits. Finally, the STS Bases Section
includes a table of the initial values of reactor vessel material properties
and includes figures showing the effects of neutron fluence on the material
characteristics and the predicted shifts in material characteristics.
The current STS bases provide extensive background information on the use of
the data obtained from material specimens. This background information
clearly defines the purpose and relationship of this information to the
requirements included in the regulations and the American Society of
Mechanical Engineers (ASME) Code. Therefore, the removal of the schedule
for specimen withdrawal from the TS will not result in any loss of clarity
related to regulatory requirements of Appendix H to 10 CFR Part 50.
If the Bases Section of this TS includes a reference to the TS table that
provides the schedule for material specimen withdrawal that is being removed
from
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Generic Letter 91-01 - 2 - Enclosure
the TS, this section should be updated to reflect the removal of this TS
table. However, to obtain a readily available copy of the NRC-approved
version of the specimen withdrawal schedule, licensees should provide a
commitment to include this schedule in the next revision of the updated
safety analysis report (USAR).
Summary:
The removal from the TS of the schedule for the withdrawal of reactor vessel
material surveillance specimens will not result in any loss of regulatory
control because changes to this schedule are controlled by the requirements
of Appendix H to 10 CFR Part 50. In addition, to ensure that the
surveillance specimens are withdrawn at the proper time, the surveillance
requirements in the TS on pressure and temperature limits must indicate that
the specimens shall be removed and examined to determine changes in their
material properties, as required by Appendix H. A request for a license
amendment to remove this table from the TS may be made based upon this
guidance. Licensees should include an updated Bases Section for this TS
with this proposal if changes to the Bases Section are necessary to remove
references to the table being removed from the TS. Also, the licensee
should commit to maintain the NRC-approved version of the specimen
withdrawal schedule in the USAR.
