[Federal Register Volume 72, Number 52 (Monday, March 19, 2007)]
[Notices]
[Pages 12838-12845]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-4939]
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NUCLEAR REGULATORY COMMISSION
Notice of Availability of Model Application Concerning Technical
Specification Improvement Regarding Deletion of E Bar Definition and
Revision to Reactor Coolant System Specific Activity Technical
Specification Using the Consolidated Line Item Improvement Process
AGENCY: Nuclear Regulatory Commission.
ACTION: Notice of Availability
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SUMMARY: Notice is hereby given that the staff of the U.S. Nuclear
Regulatory Commission (NRC) has prepared a model license amendment
request (LAR), model safety evaluation (SE), and model proposed no
significant hazards consideration (NSHC) determination related to
deletion of the E Bar definition and revision to reactor coolant system
(RCS) specific activity technical specification. This request revises
the RCS specific activity specification for pressurized water reactors
to utilize a new indicator, Dose Equivalent Xenon-133 instead of the
current indicator known as E Bar.
The purpose of these models is to permit the NRC staff to
efficiently process amendments to incorporate these changes into plant-
specific technical specifications (TS) for Babcock and Wilcox,
Westinghouse, and Combustion Engineering pressurized water reactors
(PWRs). Licensees of nuclear power reactors to which the models apply
can request amendments conforming to the models. In such a request, a
licensee should confirm the applicability of the model LAR, model SE
and NSHC determination to its plant.
DATES: The NRC staff issued a Federal Register Notice (71 FR 67170,
November 20, 2006) which provided a model LAR, model SE, and model NSHC
related to deletion of E Bar definition and revision to RCS specific
activity technical specification; similarly the NRC staff herein
provides a revised model LAR, a revised model SE, and a revised model
NSHC. The NRC staff can most efficiently consider applications based
upon the model LAR, which references the model SE, if the application
is submitted within one year of this Federal Register Notice.
FOR FURTHER INFORMATION CONTACT: Trent Wertz, Mail Stop: O-12H2,
Division of Inspection and Regional Support, Office of Nuclear Reactor
Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-
0001, telephone (301) 415-1568.
SUPPLEMENTARY INFORMATION:
Background
Regulatory Issue Summary 2000-06, ``Consolidated Line Item
Improvement Process (CLIIP) for Adopting Standard Technical
Specifications Changes for Power Reactors,'' was issued on March 20,
2000. The CLIIP is intended to improve the efficiency and transparency
of NRC licensing processes. This is accomplished by processing proposed
changes to the Standard Technical Specifications (STS) in a manner that
supports subsequent license amendment applications. The CLIIP includes
an opportunity for the public to comment on proposed changes to the STS
following a preliminary assessment by the NRC staff and finding that
the
[[Page 12839]]
change will likely be offered for adoption by licensees. The CLIIP
directs the NRC staff to evaluate any comments received for a proposed
change to the STS and to either reconsider the change or proceed with
announcing the availability of the change for proposed adoption by
licensees. Those licensees opting to apply for the subject change to
TSs are responsible for reviewing the NRC staff's evaluation,
referencing the applicable technical justifications, and providing any
necessary plant-specific information. Each amendment application made
in response to the notice of availability will be processed and noticed
in accordance with applicable NRC rules and procedures.
This notice involves replacement of the current PWR TS 3.4.16 limit
on RCS gross specific activity with a new limit on RCS noble gas
specific activity. The noble gas specific activity limit would be based
on a new dose equivalent Xe-133 (DEX) definition that would replace the
current E Bar average disintegration energy definition. In addition,
the current dose equivalent I-131 (DEI) definition would be revised to
allow the use of additional thyroid dose conversion factors (DCFs). By
letter dated September 13, 2005, the Technical Specification Task Force
(TSTF) proposed these changes for incorporation into the STS as TSTF-
490, Revision 0, which was referenced in the Federal Register Notice
(FRN) 71 FR 67170, of November 20, 2006, and can be viewed on the NRC's
Web page at http://www.nrc.gov/reactors/operating/licensing/techspecs.html.
Applicability
These proposed changes will revise the definition of DOSE
EQUIVALENT I-131, delete the definition of ``E Bar,'' AVERAGE
DISINTEGRATION ENERGY, add a new definition for DOSE EQUIVALENT XE-133,
and revise LCO 3.4.16 for Babcock and Wilcox, Westinghouse, and
Combustion Engineering PWRs.
To efficiently process the incoming license amendment applications,
the NRC staff requests that each licensee applying for the changes
addressed by TSTF-490, Revision 0, using the CLIIP submit an LAR that
adheres to the following model. Any variations from the model LAR
should be explained in the licensee's submittal. Variations from the
approach recommended in this notice may require additional review by
the NRC staff, and may increase the time and resources needed for the
review. Significant variations from the approach, or inclusion of
additional changes to the license, will result in staff rejection of
the submittal. Instead, licensees desiring significant variations and/
or additional changes should submit a LAR that does not claim to adopt
TSTF-490.
Public Notices
The staff issued a Federal Register Notice (71 FR 67170, November
20, 2006) that requested public comment on the NRC's pending action to
delete the E Bar definition and revise the RCS specific activity
technical specification. In particular, following an assessment and
draft safety evaluation by the NRC staff, the staff sought public
comment on proposed changes to the STS, designated TSTF-490 Revision 0.
The TSTF-490 Revision 0 can be viewed on the NRC's Web page at http://www.nrc.gov/reactors/operating/licensing/techspecs.html. TSTF-490
Revision 0 may be examined, and/or copied for a fee, at the NRC Public
Document Room, located at One White Flint North, 11555 Rockville Pike
(first floor), Rockville, Maryland. Publicly available records are
accessible electronically from the ADAMS Public Library component on
the NRC Web site, (the Electronic Reading Room) at http://www.nrc.gov/reading-rm/adams.html.
In response to the notice soliciting comments from the interested
members of the public about NRC's pending action to delete the E Bar
definition and revise the RCS specific activity technical
specification, the staff received four sets of comments (from licensees
and the TSTF Owners Groups, representing the licensees). Specific
comments on the model SE, model LAR, and the model NSHC were offered,
and are summarized and discussed below:
1. Comment: In Sections 3.1.4 and 3.1.7 the model safety evaluation
states: ``In MODES 5 and 6, the steam generators are not used for decay
heat removal, the RCS and steam generators are depressurized, and
primary to secondary leakage is minimal.'' However, using the
Westinghouse Standard Technical Specifications as an example, NUREG-
1431, Vol. 2, Rev. 3.0, Bases 3.4.7 (RCS Loops-Mode 5, Loops Filled)
states ``In MODE 5 with the RCS loops filled, the primary function of
the reactor coolant is the removal of decay heat and transfer this heat
either to the steam generator (SG) secondary side coolant via natural
circulation (Ref. 1) or the component cooling water via the residual
heat removal (RHR) heat exchangers.'' Therefore, the steam generators
are taken credit for as a means of removing decay heat during MODE 5.
Additionally, the RCS may be pressurized during MODE 5. The statement
as written in the model safety evaluation may prevent licensees from
stating that their application is consistent with the model technical
evaluation.
Response: The comment addresses the MODES for which the LCO would
be applicable. The NRC staff agrees that the statement in sections
3.1.4 and 3.1.7 does not acknowledge the condition of MODE 5 with the
RCS loops filled. The Model SE will be modified to account for this
condition.
2. Comment: There is currently one Technical Specification (TS)
3.4.16 limit on RCS gross specific activity, not ``limits''. The single
limit is 100/E Bar in all 3 affected STS NUREGs. There are two places
that refer to limits (plural).
Response: This editorial comment is correct, and the Supplemental
Information section and the Model LAR will be revised accordingly.
3. Comment: In the Model SE, Section 2.0: Correct the title of TID
14844. ``Reactor'' is singular in the title.
Response: This editorial comment is correct, and the Model SE will
be revised accordingly.
4. Comment: In the Model SE, Section 3.1.1: The list of Dose
Conversion Factor (DCF) references should be bracketed since this
change will be subject to plant specific considerations. The optional
DCF reference included in TSTF-490, and discussed in the traveler's
justification section 3.0 (paragraph 2, lines 4-9), for alternate
source term plants should be included here as follows:
] or [Committed Dose Equivalent (CDE) or Committed Effective Dose
Equivalent (CEDE) dose conversion factors from Table 2.1 of EPA
Federal Guidance Report No. 11.]
Response: The Model SE endorsed the use of DCFs from Table 2.1 of
FGR-11, 1988, ``Limiting Values of Radionuclide Intake and Air
Concentration and Dose Conversion Factors for Inhalation, Submersion,
and Ingestion.'' As stated in the model SE, it is incumbent on the
licensee to ensure that the DCFs used in the determination of DEI are
consistent with the DCFs used in the applicable dose consequence
analyses. As such, the references for the applicable DCFs would indeed
be plant specific and the model SE has been changed accordingly.
5. Comment: In the model SE, Section 3.1.2: All noble gas isotope
lists and DCF citations should be bracketed since these changes are
subject to plant specific considerations. The 2nd paragraph is missing
a forward slash mark between the words ``and'' and ``or'' in the text
``by tritium and corrosion and activation products * * *''
[[Page 12840]]
Response: This editorial comment is correct, and the Model SE will
be corrected.
6. Comment: In the Model SE, Section 3.1.3: The discussion on
revised Required Action A.1 should be relocated to Model SE Section
3.1.5 that discusses the changes to TS 3.4.16 condition A.
Response: The NRC staff agrees that the discussion on revised
Required Action A.1 should be relocated. The Model SE will be updated
to reflect the change.
7. Comment: In the Model SE Section 3.1.6: This section states that
Condition ``C'' is replaced with a new Condition ``B''. This is only
true for the B&W and CE STS NUREGs (1430 and 1432). It is not true for
the Westinghouse STS NUREG-1431, and it should also be noted that the
Westinghouse plants developed this traveler for submittal to the NRC.
This section should state that ``TS 3.4.16 Condition B [in NUREG-1431;
C in NUREG-1430 and NUREG-1432] is replaced with a new Condition B for
DEX not within limits.''
Section 3.1.6 should also discuss the addition of the LCO 3.0.4.c
Note to revised Required Action B.1, consistent with the Model
Application, Enclosure 1, Section 2.0, item C. Suggested wording that
could be used for this purpose is:
A Note is also added to the revised Required Action B.1 that
states LCO 3.0.4.c is applicable. This Note would allow entry into a
Mode or other specified condition in the LCO Applicability when LCO
3.4.16 is not being met and is the same Note that is currently
stated for Required Actions A.1 and A.2. The proposed Note would
allow entry into the applicable Modes when the DEX is not within its
limit; in other words, the plant could go up in the Modes from Mode
4 to Mode 1 (power operation) while the DEX limit is exceeded and
the DEX is being restored to within its limit. This Mode change
allowance is acceptable due to the significant conservatism
incorporated into the DEX specific activity limit, and the ability
to restore transient specific activity excursions while the plant
remains at, or proceeds to, power operation.
Response: The NRC staff agrees with the wording with this editorial
comment and the Model SE will be updated to reflect the differences in
the NUREGs. Also, a discussion concerning the LCO 3.0.4.c note to
required Action B.1 will be added to the Model SE Section 3.1.6.
8. Comment: In the Model SE, Section 3.1.8: This section
incorrectly states that revised SR 3.4.16.1 has a new LCO 3.0.4.c Note.
It should state that SR 3.4.16.1 has a new performance modifying Note
that reads: ``Only required to be performed in Mode 1.'' The
application of this style of Note is discussed in Example 1.4-5 in the
latest revision of the STS NUREGs. The LCO 3.0.4.c Note addition
applies only to revised Required Action B.1
Response: The NRC staff believes that the new Note for SR 3.4.16.1
is consistent with Example 1.4-5 and the Note in SR 3.4.16.2 and
therefore does not need to be changed.
9. Comment: In the Model SE, Section 3.1.2 states ``The
determination of DOSE EQUIVALENT XE-133 shall be performed using
effective dose conversion factors for air submersion listed in Table
III.1 of EPA Federal Guidance Report No. 12 or the average gamma
disintegration energies as provided in ICRP Publication 38,
``Radionuclide Transformations'' or similar source.'' What exactly is
``similar source''? Does ``similar source'' apply to average gamma
energies or to the DCFs such as published in Reg. Guide 1.109?
Response: The selection of the dose conversion factors used in the
definition of DEX should be consistent with the dose conversion factors
currently employed in the licensee's dose consequence analyses and as
such the reference for the dose conversion factors or the source of the
gamma energies used in the definition will be site specific. Brackets
will be placed around the references to indicate where site specific
information should be included.
10. Comment: In the Model SE, Section 3.1.2 states ``* * * the
calculation of DEX is based on the acute dose to the whole body and
considers the noble gases KR-85M, KR-87, KR-88, XE-133M, XE-133, XE-
135M, XE-135 and XE-133 * * *''. Under the same Section two additional
nuclides are added to the new definition for E-AVERAGE DISINTEGRATION
ENERGY; Kr-85 and XE-131M. The addition of the additional nuclides
appears to conflict with the preceding technical Evaluation. Is it the
expectation that these two nuclides be added to the DEX calculation in
addition to those listed in the preceding section?
Response: The selection of the isotopes used in the definition of
DEX will be site specific and based on the dose significant noble gas
isotopes identified in the appropriate DBA dose consequence analyses.
The list of noble gas isotopes will be placed in brackets to indicate
that the actual list will be site specific.
11. Comment: The title of TSTF-490 is not capitalized consistently
and is not consistent with the submitted Traveler. The title of TSTF-
490 is ``Deletion of E Bar Definition and Revision to RCS Specific
Activity Tech Spec.'' Note that there is no hyphen used in the term ``E
Bar.''
Response: This editorial comment is correct, and the Model SE will
be corrected.
12. Comment: In the proposed NSHC, to be consistent with 10 CFR
50.92(c)(2), the title of Criterion 2 should be revised to add the word
``Accident'' before ``Previously Evaluated.'' Specifically, it should
state, ``The Proposed Change Does Not Create the Possibility of a New
or Different Kind of Accident from any Accident Previously Evaluated.''
Response: This editorial comment is correct, and the proposed NSHC
will be corrected.
13. Comment: In the Model LAR it states, ``I declare under penalty
of perjury under the laws of the United States of America that I am
authorized by [LICENSEE] to make this request and that the foregoing is
true and correct.'' This statement is not consistent with the
recommended statement given in RIS 2001-18, ``Requirements for Oath and
Affirmation.'' RIS 2001-18 recommends the statement, ``I declare [or
certify, verify, state] under penalty of perjury that the foregoing is
true and correct.'' Note that RIS 2001-18 states that this statement
must be used verbatim. We recommend that the Model Application be
revised to be consistent with RIS 2001-18.
Response: The statement in the Model LAR is consistent with RIS
2001-18. The purpose of RIS 2001-18 was to inform licensees that there
is an alternative to the oath or affirmation statement contained in 28
U.S.C. 1746. Both are considered acceptable. The NRC staff includes
only the first option listed in 28 U.S.C. 1746 for brevity.
14. Comment: In the Model LAR, Section 8.0, the second reference
should be numbered. Note that Section 4.0 refers to References 1 and 2.
Response: The references in Section 8.0 are numbered, however, for
clarification, the Notice for Comment and the Notice for Availability
will be listed as separate references.
Dated at Rockville, Maryland this 8th day of March, 2007.
For The Nuclear Regulatory Commission.
Timothy J. Kobetz,
Chief, Technical Specifications Branch, Division of Inspection and
Regional Support, Office of Nuclear Reactor Regulation.
Attachment:
FOR INCLUSION ON THE TECHNICAL SPECIFICATION WEB PAGE THE
FOLLOWING EXAMPLE OF AN APPLICATION WAS PREPARED BY THE NRC STAFF TO
FACILITATE THE ADOPTION OF TECHNICAL SPECIFICATION TASK FORCE (TSTF)
[[Page 12841]]
TRAVELER TSTF-490, REVISION 0 ``DELETION OF E BAR DEFINITION AND
REVISION TO RCS SPECIFIC ACTIVITY TECH SPEC.'' THE MODEL PROVIDES
THE EXPECTED LEVEL OF DETAIL AND CONTENT FOR AN APPLICATION TO ADOPT
TSTF-490, REVISION 0. LICENSEES REMAIN RESPONSIBLE FOR ENSURING THAT
THEIR ACTUAL APPLICATION FULFILLS THEIR ADMINISTRATIVE REQUIREMENTS
AS WELL AS NRC REGULATIONS.
U.S. Nuclear Regulatory Commission,
Document Control Desk,
Washington, DC 20555.
SUBJECT: PLANT NAME, DOCKET NO. 50-[xxx,] RE: APPLICATION FOR
TECHNICAL SPECIFICATION IMPROVEMENT TO ADOPT TSTF-490, REVISION 0,
``DELETION OF E BAR DEFINITION AND REVISION TO RCS SPECIFIC ACTIVITY
TECH SPEC''
Dear Sir or Madam: In accordance with the provisions of Section
50.90 of Title 10 of the Code of Federal Regulations (10 CFR),
[LICENSEE] is submitting a request for an amendment to the technical
specifications (TS) for [PLANT NAME, UNIT NOS.]. The proposed
changes would replace the current pressurized water reactor (PWR)
Technical Specification (TS) 3.4.16 limit on reactor coolant system
(RCS) gross specific activity with a new limit on RCS noble gas
specific activity. The noble gas specific activity limit would be
based on a new dose equivalent Xe-133 (DEX) definition that would
replace the current E Bar average disintegration energy definition.
In addition, the current dose equivalent I-131 (DEI) definition
would be revised to allow the use of additional thyroid dose
conversion factors (DCFs).
The changes are consistent with NRC-approved Industry Technical
Specification Task Force (TSTF) Standard Technical Specification
Change Traveler, TSTF-490, Revision 0, ``Deletion of E Bar
Definition and Revision to RCS Specific Activity Tech Spec.'' The
availability of this TS improvement was announced in the Federal
Register on [DATE] ([ ]FR[ ]) as part of the consolidated line item
improvement process (CLIIP).
Enclosure 1 provides a description and assessment of the
proposed changes, as well as confirmation of applicability.
Enclosure 2 provides the existing TS pages and TS Bases marked-up to
show the proposed changes. Enclosure 3 provides final TS pages and
TS Bases pages.
[LICENSEE] requests approval of the proposed license amendment
by [DATE], with the amendment being implemented [BY DATE OR WITHIN X
DAYS]. In accordance with 10 CFR 50.91, a copy of this application,
with enclosures, is being provided to the designated [STATE]
Official.
I declare under penalty of perjury under the laws of the United
States of America that I am authorized by [LICENSEE] to make this
request and that the foregoing is true and correct. [Note that
request may be notarized in lieu of using this oath or affirmation
statement]. If you should have any questions regarding this
submittal, please contact [ ].
Sincerely,
Name, Title
Enclosures:
1. Description and Assessment of Proposed Changes
2. Proposed Technical Specification Changes and Technical
Specification Bases Changes
3. Final Technical Specification and Bases pages
cc: NRR Project Manager
Regional Office
Resident Inspector
State Contact
ITSB Branch Chief
1.0 Description
This letter is a request to amend Operating License(s) [LICENSE
NUMBER(S)] for [PLANT/UNIT NAME(S)].
The proposed changes would replace the current limits on primary
coolant gross specific activity with limits on primary coolant noble
gas activity. The noble gas activity would be based on DOSE
EQUIVALENT XE-133 and would take into account only the noble gas
activity in the primary coolant. The changes were approved by the
NRC staff Safety Evaluation (SE) dated September 27, 2006 (ADAMS
ML062700612) (Reference 1). Technical Specification Task Force
(TSTF) change traveler TSTF-490, Revision 0, ``Deletion of E Bar
Definition and Revision to RCS Specific Activity Tech Spec'' was
announced for availability in the Federal Register on [DATE] as part
of the consolidated line item improvement process (CLIIP).
2.0 Proposed Changes
Consistent with NRC-approved TSTF-490, Revision 0, the proposed
TS changes:
Revise the definition of DOSE EQUIVALENT I-131.
Delete the definition of ``E Bar, AVERAGE
DISINTEGRATION ENERGY.
Add a new TS definition for DOSE EQUIVALENT XE-133.
Revise LCO 3.4.16, ``RCS Specific Activity'' to delete
references to gross specific activity; add limits for DOSE
EQUIVALENT I-131 and DOSE EQUIVALENT XE-133; and delete Figure
3.4.16-1, ``Reactor Coolant DOSE EQUIVALENT I-131 Specific Activity
Limit versus Percent of RATED THERMAL POWER.''
Revise LCO 3.4.16 ``Applicability'' to specify the LCO
is applicable in MODES 1, 2, 3, and 4.
Modify ACTIONS Table as follows:
A. Condition A is modified to delete the reference to Figure
3.4.16-1, and define an upper limit that is applicable at all power
levels.
B. NUREG-1430 and NUREG-1432 ACTIONS are reordered, moving
Condition C to Condition B to be consistent with the Writer's Guide.
C. Condition B (was Condition C in NUREG-1430 and NUREG-1432) is
modified to provide a Condition and Required Action for DOSE
EQUIVALENT XE-133 instead of gross specific activity. The Completion
Time is changed from 6 hours to 48 hours. A Note allowing the
applicability of LCO 3.0.4.c is added, consistent with the Note to
Required Action A.1.
D. Condition C (was Condition B in NUREG-1430 and NUREG-1432) is
modified based on the changes to Conditions A and B and to reflect
the change in the LCO Applicability.
Revise SR 3.4.16.1 to verify the limit for DOSE
EQUIVALENT XE-133. A Note is added, consistent with SR 3.4.16.2 to
allow entry into MODES 2, 3, and 4 prior to performance of the SR.
Delete SR 3.4.16.3.
3.0 Background
The background for this application is as stated in the model SE
in NRC's Notice of Availability published on [DATE ]([ ] FR [ ]),
the NRC Notice for Comment published on [DATE] ([ ] FR [ ]), and
TSTF-490, Revision 0.
4.0 Technical Analysis
[LICENSEE] has reviewed References 1, 2 and 3, and the model SE
published on [DATE] ([ ]FR [ ]) as part of the CLIIP Notice for
Comment. [LICENSEE] has applied the methodology in Reference 1 to
develop the proposed TS changes. [LICENSEE] has also concluded that
the justifications presented in TSTF-490, Revision 0 and the model
SE prepared by the NRC staff are applicable to [PLANT, UNIT NOS.],
and justify this amendment for the incorporation of the changes to
the [PLANT] TS.
5.0 Regulatory Analysis
A description of this proposed change and its relationship to
applicable regulatory requirements and guidance was provided in the
NRC Notice of Availability published on [DATE] ([ ] FR [ ]), the NRC
Notice for Comment published on [DATE] ([ ] FR [ ]), and TSTF-490,
Revision 0.
6.0 No Significant Hazards Consideration
[LICENSEE] has reviewed the proposed no significant hazards
consideration determination published in the Federal Register on
[DATE] ([ ] FR [ ]) as part of the CLIIP. [LICENSEE] has concluded
that the proposed determination presented in the notice is
applicable to [PLANT] and the determination is hereby incorporated
by reference to satisfy the requirements of 10 CFR 50.91(a).
7.0 Environmental Evaluation
[LICENSEE] has reviewed the environmental consideration included
in the model SE published in the Federal Register on [DATE] ([ ] FR
[ ]) as part of the CLIIP. [LICENSEE] has concluded that the staff's
findings presented therein are applicable to [PLANT] and the
determination is hereby incorporated by reference for this
application.
8.0 References
1. NRC Safety Evaluation (SE) approving TSTF-490, Revision 0
dated September 27, 2006.
2. Federal Notice for Comment published on [DATE] ([ ] FR [ ]).
3. Federal Notice of Availability published on [DATE] ([ ] FR [
]).
Model Safety Evaluation
U.S. Nuclear Regulatory Commission, Office of Nuclear Reactor
Regulation,
[[Page 12842]]
Technical Specification Task Force TSTF-490, Revision 0, ``Deletion
of E Bar Definition and Revision to RCS Specific Activity Tech
Spec''
1.0 Introduction
By letter dated [--------, 20--], [LICENSEE] (the licensee)
proposed changes to the technical specifications (TS) for [PLANT
NAME]. The requested changes are the adoption of TSTF-490, Revision
0, ``Deletion of E Bar Definition and Revision to RCS Specific
Activity Tech Spec'' for pressurized water reactor (PWR) Standard
Technical Specifications (STS). By letter dated September 13, 2005,
the Technical Specification Task Force (TSTF) submitted TSTF-490 for
Nuclear Regulatory Commission (NRC) staff review. This TSTF involves
changes to NUREG-1430, NUREG-1431, and NUREG-1432 STS Section 3.4.16
reactor coolant system (RCS) gross specific activity limits with the
addition of a new limit for noble gas specific activity. The noble
gas specific activity limit would be based on a new dose equivalent
Xe-133 (DEX) definition that replaces the current E Bar average
disintegration energy definition. In addition, the current dose
equivalent I-131 (DEI) definition would be revised to allow the use
of additional thyroid dose conversion factors (DCFs).
2.0 Regulatory Evaluation
The NRC staff evaluated the impact of the proposed changes as
they relate to the radiological consequences of affected design
basis accidents (DBAs) that use the RCS inventory as the source
term. The source term assumed in radiological analyses should be
based on the activity associated with the projected fuel damage or
the maximum RCS technical specifications (TS) values, whichever
maximizes the radiological consequences. The limits on RCS specific
activity ensure that the offsite doses are appropriately limited for
accidents that are based on releases from the RCS with no
significant amount of fuel damage.
The Steam Generator Tube Rupture (SGTR) accident and the Main
Steam Line Break (MSLB) accident typically do not result in fuel
damage and therefore the radiological consequence analyses are based
on the release of primary coolant activity at maximum TS limits. For
accidents that result in fuel damage, the additional dose
contribution from the initial activity in the RCS is not normally
evaluated and is considered to be insignificant in relation to the
dose resulting from the release of fission products from the damaged
fuel.
For licensees that incorporate the source term as defined in
Technical Information Document (TID) 14844, AEC, 1962, ``Calculation
of Distance Factors for Power and Test Reactors Sites,'' in their
dose consequence analyses, the NRC staff uses the regulatory
guidance provided in NUREG-0800, ``Standard Review Plan (SRP) for
the Review of Safety Analysis Reports for Nuclear Power Plants,''
Section 15.1.5, ``Steam System Piping Failures Inside and Outside of
Containment (PWR),'' Appendix A, ``Radiological Consequences of Main
Steam Line Failures Outside Containment,'' Revision 2, for the
evaluation of MSLB accident analyses and NUREG-0800, SRP Section
15.6.3, ``Radiological Consequences of Steam Generator Tube Failure
(PWR),'' Revision 2, for evaluating SGTR accidents analyses. In
addition, the NRC staff uses the guidance from RG 1.195, ``Methods
and Assumptions for Evaluating Radiological Consequences of Design
Basis Accidents at Light Water Nuclear Power Reactors,'' May 2003,
for those licensees that chose to use its guidance for dose
consequence analyses using the TID 14844 source term.
For licensees using the alternative source term (AST) in their
dose consequence analyses, the NRC staff uses the regulatory
guidance provided in NUREG-0800, SRP Section 15.0.1, ``Radiological
Consequence Analyses Using Alternative Source Terms,'' Revision 0,
July 2000, and the methodology and assumptions stated in Regulatory
Guide (RG) 1.183, ``Alternative Radiological Source Terms for
Evaluating Design Basis Accidents at Nuclear Power Reactors'', July
2000.
The applicable dose criteria for the evaluation of DBAs depends
on the source term incorporated in the dose consequence analyses.
For licensees using the TID 14844 source term, the maximum dose
criteria to the whole body and the thyroid that an individual at the
exclusion area boundary (EAB) can receive for the first 2 hours
following an accident, and at the low population zone (LPZ) outer
boundary for the duration of the radiological release, are specified
in Title 10 of the Code of Federal Regulations (10 CFR) Part 100.11.
These criteria are 25 roentgen equivalent man (rem) total whole body
dose and 300 rem thyroid dose from iodine exposure. The accident
dose criteria in 10 CFR 100.11 is supplemented by accident specific
dose acceptance criteria in SRP 15.1.5, Appendix A, SRP 15.6.3 or
Table 4 of RG 1.195, ``Methods and Assumptions for Evaluating
Radiological Consequences of Design Basis Accidents at Light Water
Nuclear Power Reactors,'' May 2003.
For control room dose consequence analyses that use the TID
14844 source term, the regulatory requirement for which the NRC
staff bases its acceptance is General Design Criterion (GDC) 19 of
Appendix A to 10 CFR Part 50, ``Control Room''. GDC 19 requires that
adequate radiation protection be provided to permit access and
occupancy of the control room under accident conditions without
personnel receiving radiation exposures in excess of 5 rem whole
body, or its equivalent to any part of the body, for the duration of
the accident. NUREG-0800, SRP Section 6.4, ``Control Room
Habitability System,'' Revision 2, July 1981, provides guidelines
defining the dose equivalency of 5 rem whole body as 30 rem for both
the thyroid and skin dose. For licensees adopting the guidance from
RG 1.196, ``Control Room Habitability at Light Water Nuclear Power
Reactors,'' May 2003, Section C.4.5 of RG 1.195, May 2003, states
that in lieu of the dose equivalency guidelines from Section 6.4 of
NUREG-0800, the 10 CFR 20.1201 annual organ dose limit of 50 rem can
be used for both the thyroid and skin dose equivalent of 5 rem whole
body.
Licensees using the AST are evaluated against the dose criteria
specified in 10 CFR part 50.67(b)(2). The off-site dose criteria are
25 rem total effective dose equivalent (TEDE) at the EAB for any 2-
hour period following the onset of the postulated fission product
release and 25 rem TEDE at the outer boundary of the LPZ for the
duration of the postulated fission product release. In addition, 10
CFR part 50.67(b)(2)(iii) requires that adequate radiation
protection be provided to permit access and occupancy of the control
room under accident conditions without personnel receiving radiation
exposures in excess of 5 rem TEDE for the duration of the accident.
3.0 Technical Evaluation
3. 1 Technical Evaluation of TSTF-490 TS Changes
3.1.1 Revision to the Definition of DEI
The list of acceptable DCFs for use in the determination of DEI
include the following:
[Table III of TID-14844, AEC, 1962, ``Calculation of
Distance Factors for Power and Test Reactor Sites.'']
[Table E-7 of Regulatory Guide 1.109, Revision 1, NRC,
1977.]
[ICRP 30,1979, page 192-212, Table titled ``Committed
Dose Equivalent in Target Organs or Tissues per Intake of Unit
Activity.'']
[Committed Dose Equivalent (CDE) or Committed Effective
Dose Equivalent (CEDE) dose conversion factors from Table 2.1 of EPA
Federal Guidance Report No. 11.'']
[Table 2.1 of EPA Federal Guidance Report No. 11, 1988,
``Limiting Values of Radionuclide Intake and Air Concentration and
Dose Conversion Factors for Inhalation, Submersion, and
Ingestion.'']
Note: It is incumbent on the licensee to ensure that the DCFs
used in the determination of DEI are consistent with the applicable
dose consequence analyses.
3.1.2 Deletion of the Definition of E Bar and the Addition of a New
Definition for DE Xe-133
The new definition for DEX is similar to the definition for DEI.
The determination of DEX will be performed in a similar manner to
that currently used in determining DEI, except that the calculation
of DEX is based on the acute dose to the whole body and considers
the noble gases [Kr-85m, Kr-85, Kr-87, Kr-88, Xe-131m, Xe-133m, Xe-
133, Xe-135m, Xe-135, and Xe-138] which are significant in terms of
contribution to whole body dose. Some noble gas isotopes are not
included due to low concentration, short half life, or small dose
conversion factor. The calculation of DEX would use either the
average gamma disintegration energies for the nuclides or the
effective dose conversion factors from Table III.1 of EPA FGR No.
12. Using this approach, the limit on the amount of noble gas
activity in the primary coolant would not fluctuate with variations
in the calculated values of E Bar. If a specified noble gas nuclide
is not detected, the new definition states that it should be assumed
the nuclide is present at the minimum detectable activity. This will
result in a conservative calculation of DEX.
When E Bar is determined using a design basis approach in which
it is assumed that
[[Page 12843]]
1.0% of the power is being generated by fuel rods having cladding
defects and it is also assumed that there is no removal of fission
gases from the letdown flow, the value of E Bar is dominated by Xe-
133. The other nuclides have relatively small contributions.
However, during normal plant operation there are typically only a
small amount of fuel clad defects and the radioactive nuclide
inventory can become dominated by tritium and corrosion and/or
activation products, resulting in the determination of a value of E
Bar that is very different than would be calculated using the design
basis approach. Because of this difference, the accident dose
analyses become disconnected from plant operation and the limiting
condition for operation (LCO) becomes essentially meaningless. It
also results in a TS limit that can vary during operation as
different values for E Bar are determined.
This change will implement a LCO that is consistent with the
whole body radiological consequence analyses which are sensitive to
the noble gas activity in the primary coolant but not to other non-
gaseous activity currently captured in the E Bar definition. LCO
3.4.16 specifies the limit for primary coolant gross specific
activity as 100/E Bar --Ci/gm. The current E Bar definition includes
radioisotopes that decay by the emission of both gamma and beta
radiation. The current Condition B of LCO 3.4.16 would rarely, if
ever, be entered for exceeding 100/E Bar since the calculated value
is very high (the denominator is very low) if beta emitters such as
tritium (H-3) are included in the determination, as required by the
E Bar definition.
TS Section 1.1 definition for E--AVERAGE DISINTEGRATION ENERGY
(E Bar) is deleted and replaced with a new definition for DEX which
states:
DOSE EQUIVALENT XE-133 shall be that concentration of
Xe-133 (microcuries per gram) that alone would produce the same
acute dose to the whole body as the combined activities of noble gas
nuclides [Kr-85m, Kr-85, Kr-87, Kr-88, Xe-131m, Xe-133m, Xe-133, Xe-
135m, Xe-135, and Xe-138] actually present. If a specific noble gas
nuclide is not detected, it should be assumed to be present at the
minimum detectable activity. The determination of DOSE EQUIVALENT
XE-133 shall be performed using [effective dose conversion factors
for air submersion listed in Table III.1 of EPA Federal Guidance
Report No. 12, 1993, ``External Exposure to Radionuclides in Air,
Water, and Soil'' or the average gamma disintegration energies as
provided in ICRP Publication 38, ``Radionuclide Transformations'' or
similar source.]''
The change incorporating the newly defined quantity DEX is
acceptable from a radiological dose perspective since it will result
in an LCO that more closely relates the non-iodine RCS activity
limits to the dose consequence analyses which form their bases.
Note: It is incumbent on the licensee to ensure that the DCFs used
in the determination of DEI and the newly defined dex are consistent
with the DCFs used in the applicable dose consequence analysis.
3.1.3 LCO 3.4.16, ``RCS Specific Activity''
LCO 3.4.16 is modified to specify that iodine specific activity
in terms of DEI and noble gas specific activity in terms of DEX
shall be within limits. Currently the limiting indicators are not
explicitly identified in the LCO, but are instead defined in current
Condition C and Surveillance Requirement (SR) 3.4.16.1 for gross
non-iodine specific activity and in current Condition A and SR
3.4.16.2 for iodine specific activity.
The change states ``RCS DOSE EQUIVALENT 1-131 and DOSE
EQUIVALENT XE-133 specific activity shall be within limits.'' Note:
IT IS INCUMBENT ON THE LICENSEE TO ENSURE THAT THE SITE SPECIFIC
LIMITS FOR BOTH DEI AND DEX ARE CONSISTENT WITH THE CURRENT SGTR AND
MSLB RADIOLOGICAL CONSEQUENCE ANALYSES.
3.1.4 TS 3.4.16 Applicability
TS 3.4.16 Applicability is modified to include all of MODE 3 and
MODE 4. It is necessary for the LCO to apply during MODES 1 through
4 to limit the potential radiological consequences of an SGTR or
MSLB that may occur during these MODES. In MODE 5 with the RCS loops
filled, the steam generators are specified as a backup means of
decay heat removal via natural circulation. In this mode, however,
due to the reduced temperature of the RCS, the probability of a DBA
involving the release of significant quantities of RCS inventory is
greatly reduced. Therefore, monitoring of RCS specific activity is
not required. In MODE 5 with the RCS loops not filled and in MODE 6
the steam generators are not used for decay heat removal, the RCS
and steam generators are depressurized and primary to secondary
leakage is minimal. Therefore, the monitoring of RCS specific
activity is not required. The change to modify the TS 3.4.16
Applicability to include all of MODE 3 and MODE 4 is necessary to
limit the potential radiological consequences of an SGTR or MSLB
that may occur during these MODES and is therefore acceptable from a
radiological dose perspective.
3.1.5 TS 3.4.16 Condition A
TS 3.4.16 Condition A is revised by replacing the DEI site
specific limit ``> [1.0] [mu]Ci/gm'' with the words ``not within
limit'' to be consistent with the revised TS 3.4.16 LCO format. The
site specific DEI limit of <= [1.0] [mu]Ci/gm is contained in SR
3.4.16.2. This proposed format change will not alter current STS
requirements and is acceptable from a radiological dose perspective.
TS 3.4.16 Required Action A.1 is revised to remove the reference
to Figure 3.4.16-1 ``Reactor Coolant DOSE EQUIVALENT I-131 Specific
Activity Limit versus Percent of RATED THERMAL POWER'' and insert a
limit of less than or equal to the site specific DEI spiking limit.
The curve contained in Figure 3.4.16-1 was provided by the AEC in a
June 12, 1974 letter from the AEC on the subject, ``Proposed
Standard Technical Specifications for Primary Coolant Activity.''
Radiological dose consequence analyses for SGTR and MSLB accidents
that take into account the pre-accident iodine spike do not consider
the elevated RCS iodine specific activities permitted by Figure
3.4.16-1 for operation at power levels below 80% RTP. Instead, the
pre-accident iodine spike analyses assume a DEI concentration [60]
times higher than the corresponding long-term equilibrium value,
which corresponds to the specific activity limit associated with
100% RTP operation. It is acceptable that TS 3.4.16 Required Action
A.1 should be based on the short term site specific DEI spiking
limit to be consistent with the assumptions contained in the
radiological consequence analyses.
3.1.6 TS 3.4.16 Condition B Revision To include Action for DEX Limit
TS 3.4.16 Condition C is replaced with a new Condition B [in
NUREG-1431; C in NUREG-1430 and NUREG-1432] for DEX not within
limits. This change is made to be consistent with the change to the
TS 3.4.16 LCO which requires the DEX specific activity to be within
limits as discussed above in Section 3.1.3. The DEX limit is site
specific and the numerical value in units of [mu]Ci/gm is contained
in revised SR 3.4.16.1. The site specific limit of DEX in [mu]Ci/gm
is established based on the maximum accident analysis RCS activity
corresponding to 1% fuel clad defects with sufficient margin to
accommodate the exclusion of those isotopes based on low
concentration, short half life, or small dose conversion factors.
The primary purpose of the TS 3.4.16 LCO on RCS specific activity
and its associated Conditions is to support the dose analyses for
DBAs. The whole body dose is primarily dependent on the noble gas
activity, not the non-gaseous activity currently captured in the E
Bar definition.
The Completion Time for revised TS 3.4.16 Required Action B.1
will require restoration of DEX to within limit in 48 hours. This is
consistent with the Completion Time for current Required Action A.2
for DEI. The radiological consequences for the SGTR and the MSLB
accidents demonstrate that the calculated thyroid doses are
generally a greater percentage of the applicable acceptance criteria
than the calculated whole body doses. It then follows that the
Completion Time for noble gas activity being out of specification in
the revised Required Action B.1 should be at least as great as the
Completion Time for iodine specific activity being out of
specification in current Required Action A.2. Therefore the
Completion Time of 48 hours for revised Required Action B.1 is
acceptable from a radiological dose perspective. A Note is also
added to the revised Required Action B.1 that states LCO 3.0.4.c is
applicable. This Note would allow entry into a Mode or other
specified condition in the LCO Applicability when LCO 3.4.16 is not
being met and is the same Note that is currently stated for Required
Actions A.1 and A.2. The proposed Note would allow entry into the
applicable Modes from MODE 4 to MODE 1 (power operation) while the
DEX limit is exceeded and the DEX is being restored to within its
limit. This Mode change is acceptable due to the significant
conservatism incorporated into the DEX specific activity limit, the
low probability of an event occurring which is limiting due to
exceeding the DEX specific activity limit, and the ability to
restore
[[Page 12844]]
transient specific excursions while the plant remains at, or
proceeds to power operation.
3.1.7 TS 3.4.16 Condition C
TS 3.4.16 Condition C is revised to include Condition B (DEX not
within limit) if the Required Action and associated Completion Time
of Condition B is not met. This is consistent with the changes made
to Condition B which now provide the same completion time for both
components of RCS specific activity as discussed in the revision to
Condition B. The revision to Condition C also replaces the limit on
DEI from the deleted Figure 3.4.16-1, with a site specific value of
> [60] [mu]Ci/gm. This change makes Condition C consistent with the
changes made to TS 3.4.16 Required Action A.1.
The change to TS 3.4.16 Required Action C.1 requires the plant
to be in MODE 3 within 6 hours and adds a new Required Action C.2
which requires the plant to be in MODE 5 within 36 hours. These
changes are consistent with the changes made to the TS 3.4.16
Applicability. The revised LCO is applicable throughout all of MODES
1 through 4 to limit the potential radiological consequences of an
SGTR or MSLB that may occur during these MODES. In MODE 5 with the
RCS loops filled, the steam generators are specified as a backup
means of decay heat removal via natural circulation. In this mode,
however, due to the reduced temperature of the RCS, the probability
of a DBA involving the release of significant quantities of RCS
inventory is greatly reduced. Therefore, monitoring of RCS specific
activity is not required. In MODE 5 with the RCS loops not filled
and MODE 6, the steam generators are not used for decay heat
removal, the RCS and steam generators are depressurized, and primary
to secondary leakage is minimal. Therefore, the monitoring of RCS
specific activity is not required.
A new TS 3.4.16 Required Action C.2 Completion Time of 36 hours
is added for the plant to reach MODE 5. This Completion Time is
reasonable, based on operating experience, to reach MODE 5 from full
power conditions in an orderly manner and without challenging plant
systems and the value of 36 hours is consistent with other TS which
have a Completion Time to reach MODE 5.
3.1.8 SR 3.4.16.1 DEX Surveillance
The change replaces the current SR 3.4.16.1 surveillance for RCS
gross specific activity with a surveillance to verify that the site
specific reactor coolant DEX specific activity is <= [X] [mu]Ci/gm.
This change provides a surveillance for the new LCO limit added to
TS 3.4.16 for DEX. The revised SR 3.4.16.1 surveillance requires
performing a gamma isotopic analysis as a measure of the noble gas
specific activity of the reactor coolant at least once every 7 days,
which is the same frequency required under the current SR 3.4.16.1
surveillance for RCS gross non-iodine specific activity. The
surveillance provides an indication of any increase in the noble gas
specific activity. The results of the surveillance on DEX allow
proper remedial action to be taken before reaching the LCO limit
under normal operating conditions.
SR 3.4.16.1 is modified by inclusion of a NOTE which permits the
use of the provisions of LCO 3.0.4.c. This allowance permits entry
into the applicable MODE(S) while relying on the ACTIONS. This
allowance is acceptable due to the significant conservatism
incorporated into the specific activity limit, the low probability
of an event which is limiting due to exceeding this limit, and the
ability to restore transient specific activity excursions while the
plant remains at, or proceeds to power operation. This allows entry
into MODE 4, MODE 3, and MODE 2 prior to performing the
surveillance. This allows the surveillance to be performed in any of
those MODES, prior to entering MODE 1, similar to the current
surveillance SR 3.4.16.2 for DEI.
3.1.9 SR 3.4.16.3 Deletion
The current SR 3.4.16.3 which required the determination of E
Bar is deleted. TS 3.4.16 LCO on RCS specific activity supports the
dose analyses for DBAs, in which the whole body dose is primarily
dependent on the noble gas concentration, not the non-gaseous
activity currently captured in the E Bar definition. With the
elimination of the limit for RCS gross specific activity and the
addition of the new LCO limit for noble gas specific activity, this
SR to determine E Bar is no longer required.
3.2 Precedent
The technical specifications developed for the Westinghouse
AP600 and AP1000 advanced reactor designs incorporate an LCO for RCS
DEX activity in place of the LCO on non-iodine gross specific
activity based on E Bar. This approach was approved by the NRC staff
for the AP600 in NUREG-1512, ``Final Safety Evaluation Report
Related to the Certification of the AP600 Standard Design, Docket
No. 52-003,'' dated August 1998 and for the AP1000 in the NRC letter
to Westinghouse Electric Company dated September 13, 2004. In
addition, the curve describing the maximum allowable iodine
concentration during the 48-hour period of elevated activity as a
function of power level, was not included in the TS approved for the
AP600 and API000 advanced reactor designs.
4.0 State Consultation
In accordance with the Commission's regulations, the [------]
State official was notified of the proposed issuance of the
amendment. The State official had [(1) no comments or (2) the
following comments--with subsequent disposition by the staff].
5.0 Environmental Consideration
The amendment[s] change[s] a requirement with respect to the
installation or use of a facility component located within the
restricted area as defined in 10 CFR part 20 or surveillance
requirements. The NRC staff has determined that the amendment
involves no significant increase in the amounts, and no significant
change in the types, of any effluents that may be released offsite,
and that there is no significant increase in individual or
cumulative occupational radiation exposure. The Commission has
previously issued a proposed finding that the amendment involves no
significant hazards consideration and there has been no public
comment on such finding published [DATE] ([-] FR [-]). Accordingly,
the amendment meets the eligibility criteria for categorical
exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR
51.22(b), no environmental impact statement or environmental
assessment need be prepared in connection with the issuance of the
amendment.
6.0 Conclusion
The Commission has concluded, based on the considerations
discussed above, that (1) there is reasonable assurance that the
health and safety of the public will not be endangered by operation
in the proposed manner, (2) such activities will be conducted in
compliance with the Commission's regulations, and (3) the issuance
of the amendment will not be inimical to the common defense and
security or to the health and safety of the public.
Proposed No Significant Hazards Consideration Determination
Description of Amendment Request: [LICENSEE] requests adoption
of an approved change to the Standard Technical Specifications (STS)
for pressurized water reactor (PWR) plants (NUREG-1430, NUREG-1431,
& NUREG-1432) and plant specific technical specifications (TS), to
replace the current limits on primary coolant gross specific
activity with limits on primary coolant noble gas activity. The
noble gas activity would be based on DOSE EQUIVALENT XE-133 and
would take into account only the noble gas activity in the primary
coolant. The changes are consistent with NRC approved Industry/
Technical Specification Task Force (TSTF) Standard Technical
Specification Change Traveler, TSTF-490, Revision 0.
Basis for proposed no-significant-hazards-consideration
determination: As required by 10 CFR 50.91(a), an analysis of the
issue of no-significant-hazards-consideration is presented below:
Criterion 1--The Proposed Change Does Not Involve a Significant
Increase in the Probability or Consequences of an Accident
Previously Evaluated
Reactor coolant specific activity is not an initiator for any
accident previously evaluated. The Completion Time when primary
coolant gross activity is not within limit is not an initiator for
any accident previously evaluated. The current variable limit on
primary coolant iodine concentration is not an initiator to any
accident previously evaluated. As a result, the proposed change does
not significantly increase the probability of an accident. The
proposed change will limit primary coolant noble gases to
concentrations consistent with the accident analyses. The proposed
change to the Completion Time has no impact on the consequences of
any design basis accident since the consequences of an accident
during the extended Completion Time are the same as the consequences
of an accident during the Completion Time. As a result, the
consequences of any accident previously evaluated are not
significantly increased.
Criterion 2--The Proposed Change Does Not Create the Possibility
of a New or Different Kind of Accident from any Accident Previously
Evaluated
The proposed change in specific activity limits does not alter
any physical part of the
[[Page 12845]]
plant nor does it affect any plant operating parameter. The change
does not create the potential for a new or different kind of
accident from any previously calculated.
Criterion 3--The Proposed Change Does Not Involve a Significant
Reduction in the Margin of Safety
The proposed change revises the limits on noble gase
radioactivity in the primary coolant. The proposed change is
consistent with the assumptions in the safety analyses and will
ensure the monitored values protect the initial assumptions in the
safety analyses.
Based upon the reasoning presented above and the previous
discussion of the amendment request, the requested change does not
involve a significant hazards consideration.
Dated at Rockville, Maryland this ----th day of ----, ----.
For The Nuclear Regulatory Commission.
Project Manager,
Plant Licensing Branch [ ], Division of Operating Reactor Licensing,
Office of Nuclear Reactor Regulation.
[FR Doc. E7-4939 Filed 3-16-07; 8:45 am]
BILLING CODE 7590-01-P