[Federal Register Volume 64, Number 125 (Wednesday, June 30, 1999)]
[Notices]
[Pages 35194-35197]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-16597]


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NUCLEAR REGULATORY COMMISSION


Licensee Qualification for Performing Safety Analyses; Issue

AGENCY: Nuclear Regulatory Commission.

ACTION: Notice of Issuance.

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SUMMARY: The Nuclear Regulatory Commission (NRC) has issued Supplement 
1 to Generic Letter (GL) 83-11, Licensee Qualification for Performing 
Safety Analyses, to all holders of operating licenses for nuclear power 
reactors. This GL supplement presents criteria that licensees may 
choose to comply with to verify to the NRC their qualifications to use 
approved codes and methods for performing safety analyses.

DATES: The GL supplement was issued on June 24, 1999.

ADDRESSES: Not applicable.

FOR FURTHER INFORMATION CONTACT: Laurence I. Kopp, Office of Nuclear 
Reactor Regulation, U.S. Nuclear Regulatory Commission, telephone 301-
415-2879, e-mail [email protected].

SUPPLEMENTARY INFORMATION: In 1995, the Nuclear Regulatory Commission 
(NRC) prepared a draft of a supplement to Generic Letter 83-11, 
Licensee Qualification for Performing Safety Analyses, for the purpose 
of presenting criteria that licensees may choose to comply with to 
verify to the NRC their qualifications to use approved codes and 
methods for performing safety analyses. By complying with these 
criteria, a licensee would eliminate the need to submit a topical 
report for qualifying their use of a previously approved methodology. A 
notice of opportunity for public comment including a draft of the 
supplement were published in the Federal Register on October 25, 1995 
(60 FR 54712). NRC staff responses to the comments received are 
presented below under the heading ``Discussion of Comments.''
    The NRC subsequently decided to cancel the issuance of the generic 
letter supplement primarily because of issues that had arisen at a 
nuclear power facility (Maine Yankee) regarding the improper 
application of approved methods. At that time, the NRC concluded that 
the potential reduction in staff oversight which would result from its 
issuance was not justified. A notice of cancellation was published in 
the Federal Register on October 30, 1996 (61 FR 56069). The specific 
issue that arose concerned the licensee's failure to comply with all of 
the restrictions and conditions stated in the

[[Page 35195]]

staff's safety evaluation report (SER) for proper application of a 
loss-of-coolant-accident (LOCA) code.
    A review of the lessons learned from Maine Yankee has indicated 
that the issue involved was adequately addressed in the generic letter 
supplement as published for public comment on October 25, 1995, because 
the supplement requires that licensees adhere to all limitations and 
restrictions in the staff's SER. Further, this supplement to GL 83-11 
does not apply to LOCA codes. Therefore, the NRC determined that there 
would be no reduction in staff oversight and decided to proceed with 
issuance of the supplement.
    The GL supplement is available in the NRC Public Document Room 
under accession number 9906210103.

Discussion of Comments

    Comments were received from 13 licensees, 3 fuel vendors, and 3 
industry interest groups, in response to the notice of opportunity for 
public comment noted above. Following are the staff responses to 
comments received on the proposed GL 83-11 supplement:

Studsvik of America, Inc.

    Comment: Clarify that ``safety analysis'' includes the physics 
parameters and codes used to generate them.
    Response: Clarification has been made in both the Purpose section 
and 2.0 Guidelines section.
    Comment: For physics codes, approval of code should be separate 
from the application method.
    Response: Section 2.2 has been modified to clarify that in some 
instances the approval of the code is separate from the application 
method.
    Comment: Clarification of what constitutes NRC approval of a code 
and/or method would be helpful.
    Response: Section 2.1 has been modified to clarify the eligibility 
of codes and methods for this process.
    Comment: Clarify what constitutes a significant code and/or 
methodology update that must be reviewed by the NRC.
    Response: What constitutes a significant code or methodology update 
that must be reviewed by the NRC is too complex a topic to fully 
address in a generic manner at this time. However, as mentioned in the 
Federal Register notice (October 25, 1995 (60 FR 54712)), the NRC is 
also investigating modified procedures for reducing the resource effort 
for acceptance of new or revised licensee or vendor analysis methods. 
Therefore, it is anticipated that this topic will be addressed at a 
future date.

Westinghouse Electric Corporation

    Comment: Reemphasize that NRC's experience has shown that a large 
percentage of all errors or discrepancies discovered in safety analyses 
can be traced to the user rather than the code itself.
    Response: The fact that NRC's experience has shown that many times 
errors or discrepancies discovered in safety analyses can be traced to 
the user rather than the code itself is stated in the Description of 
Circumstances section.

Florida Power & Light Company

    Comment: NRC should allow licensees to modify the Core Operating 
Limit Report (COLR) without specific NRC review so long as the methods 
and codes have already been approved by the NRC.
    Response: The issuance of this supplement would allow this 
modification as long as the approved methodology is referenced in the 
technical specifications. The Introduction and Section 2.0 have been 
modified to address this.

Duke Power Company

    Comment: NRC should generically lift restrictions included in 
topical report SERs that restricted application of the methodology to 
the plants operated or supported by the licensee of the methodology.
    Response: The issuance of this supplement would generically lift 
these restrictions. However, any other limitations stated in the SERs 
should be adhered to.
    Comment: The introduction should state that the codes are developed 
by vendors, utilities, national labs, or organizations like EPRI.
    Response: The proposed statement has been added to the 
Introduction.
    Comment: The scope of safety analyses should be defined to cover 
any analytical areas including reload physics design, core thermal-
hydraulics, fuel mechanical analysis, transient analysis, dose 
analysis, setpoint analysis, containment analysis, criticality 
analysis, statistical methods, and any other analytical area for which 
topical reports have been approved by the NRC.
    Response: The suggested clarification has been incorporated in the 
Purpose and 2.0 Guidelines sections, with the exception of LOCA 
analysis codes.

Nuclear Energy Institute

    Comment: Recommends deletion of last two items in Section 2.5.
    Response: The NRC believes that the two items emphasized are of 
sufficient significance to be explicitly stated.
    Comment: Recommends rewording of Section 2.4 so as not to imply all 
of the suggested set of benchmark data is required.
    Response: The wording in Section 2.4 has been modified to clarify 
that these are examples of appropriate benchmark data and are not all 
required.

Commonwealth Edison Company

    Comment: Terminology and criteria are open to interpretation. For 
example, in Section 2.4, what the licensee may think is appropriate 
justification for an observed deviation in comparison calculations may 
satisfy one reviewer but not another.
    Response: Suggested rewording for benchmark deviations has been 
added to Section 2.4 to eliminate ambiguity.
    Comment: The intent of the term ``application procedure'' in 
Section 2.2 could be misinterpreted.
    Response: Section 2.2 has been revised for clarification.
    Comment: Section 2.4 should be revised to read ``Significant, 
unexpected, or unusual deviations should be * * *''
    Response: The suggested rewording has been added to Section 2.4.
    Comment: Vendor update implementation in Section 2.5 should be 
clarified so as not to imply that all changes that vendor makes must be 
implemented.
    Response: Section 2.5 Item (1) has been modified to allow an 
evaluation of updates to determine if implementation is required.

Electric Power Research Institute

    Comment: Questions whether a licensee must base the methodology on 
a previously approved plant SER or can develop a ``new'' topical based 
only on the generic code SER?
    Response: By adhering to the guidelines in the supplement, a 
licensee can perform its own analyses using any approved code or 
method.
    Comment: For clarity, the words ``application of the'' should be 
deleted from Section 2.2.
    Response: The in-house application procedures should be consistent 
with the code qualification and approved application of the 
methodology. Therefore, this has been retained in Section 2.2.
    Comment: Training should be performed by either the developer or 
someone who has been previously qualified.
    Response: The proposed wording has been added to Section 2.3.

[[Page 35196]]

    Comment: ``Vendor'' analysis should be changed to ``analysis of 
record.''
    Response: The proposed rewording has been added to Section 2.4.
    Comment: An appropriate set of benchmark data should include 
analysis of events, using higher order codes or published numerical 
benchmarks.
    Response: The proposed wording has been added to Section 2.4.
    Comment: In Section 2.4, ``Any deviations'' should be explained.
    Response: A revision has been made to Section 2.4 to more clearly 
define deviations that must be explained.

Southern Nuclear Operating Company

    Concurs with NEI comments.

GPU Nuclear Corporation

    Comment: It seems appropriate to identify existing codes and 
methodologies that have been developed by national labs for the NRC 
that can be considered NRC approved codes and methods.
    Response: The identification of existing codes and methodologies 
developed by national labs that can be considered as NRC approved codes 
and methods, even though formal NRC review and approval has never been 
performed, is beyond the scope of this proposed supplement.
    Comment: Suggests that the terms ``codes'', ``methods'', and 
``applications'' be clearly defined.
    Response: A definition of codes, methods, and applications has been 
added to the Introduction.

Siemens Power Corporation

    Supports the approaches described in the proposed supplement.

Virginia Power

    Endorses the proposed supplement.

Pacific Gas and Electric Company

    Comment: Concept should not be limited to core analysis.
    Response: The specific analytical areas that the GL refers to have 
been added to the Purpose Section.
    Comment: NRC should allow the training requirement to be met by on-
the-job training.
    Response: A new user can be qualified by on-the-job training as 
well as by formal classroom instruction. In many cases, user 
qualification will be accomplished by a combination of both

Yankee Atomic Electric Company (YAEC)

    Comment: It is YAEC's understanding that the supplement will only 
apply to licensees who use another organization's methods and codes, 
and not to an organization that receives approval for its own codes and 
methods, and conducts safety analyses using those codes and methods.

Response: YAEC's interpretation is correct.

    Comment: Recommends that the supplement also note that other 
organizations such as utilities and engineering service companies have 
developed codes and methods.
    Response: The example of possible code developers has been modified 
to include utilities and national labs.

Indiana Michigan Power Company

    Comment: Suggests that different versions of previously approved 
codes should be applicable as long as the calculational methodology is 
not changed.
    Response: Section 2.1 has been modified to clarify code 
eligibility. What constitutes a significant code or methodology update 
that must be reviewed by the NRC is too complex a topic to fully 
address in generic terms at this time. However, as mentioned in the 
Federal Register notice (60 FR 54712; October 25, 1995), the NRC is 
also investigating modified procedures for reducing the resource effort 
for acceptance of new or revised licensee or vendor analysis methods. 
Therefore, it is anticipated that this topic will be addressed at a 
future date.

Entergy Operations, Incorporated

    Comment: The applicability of a particular method to either a 
specific fuel design or to a core which contains a mixture of fuel 
types is important. Use of one vendor's hot channel analysis code with 
another's transient codes may not necessarily yield conservative 
results and may not be consistent with the NRC-approved reload analysis 
package. In-house application procedures should have proper controls to 
preclude such a misapplication, and should be permitted to include the 
flexibility to perform comparison tests between the different 
methodologies to show that a conservative assessment can be made.
    Response: Section 2.2 has been modified to incorporate this 
application procedure.
    Comment: NRC should consider issuing an inspection procedure 
concurrently with the supplement so that licensees would know what 
questions and documentation requests might be needed to support audits.
    Response: The NRC will incorporate oversight of this GL supplement 
into the NRC inspection program following the issuance of this 
supplement.
    Comment: NRC should consider providing licensees the flexibility to 
conduct its own assessment of a third party reviewer similar to what is 
currently allowed in NRC Inspection Module 40501.
    Response: Issuance of this supplement would eliminate the need to 
submit a qualification topical report for NRC review and thus eliminate 
the need for a third party reviewer.

Arizona Public Service (APS)

    Comment: The ``first licensing application'' is interpreted by APS 
as being the first proposed license amendment or other licensing basis 
change requiring prior NRC review and approval that was supported by 
safety analyses performed by the licensee instead of a vendor.
    Response: The ``first licensing application'' may not necessarily 
be a licensing basis change requiring NRC approval before 
implementation, but may be a revision to a COLR parameter, for example.
    Comment: APS would interpret ``eligibility'' in Section 2.1 to mean 
that code packages previously approved in topical reports or license 
amendments for other plants would be generically approved.
    Response: The only codes and methods that are eligible for this 
process are those that have been generically approved, or those that 
have been otherwise accepted as part of a plant's licensing basis. 
Section 2.1 has been modified to clarify this.
    Comment: APS suggests that plant specific uncertainties could be 
used without additional NRC review, even if these uncertainties are 
less than the generically approved uncertainties.
    Response: As a general rule, plant specific uncertainties may be 
used without additional NRC review provided that they are derived with 
previously approved methods. However, NRC review is required for 
modifications to uncertainties that were generically approved to cover 
uncertainties due to codes and methods, correlations, etc.
    Comment: APS states that they would control changes to methodology 
by design control procedures and that the changes would be subject to 
10 CFR 50.59 evaluations, if appropriate.
    Response: As stated in Section 2.1, the use of a new methodology or 
a change to an existing methodology is not applicable to this process. 
However, as mentioned in the Federal Register notice (60 FR 54712; 
October 25, 1995), the NRC is also investigating modified procedures 
for reducing the resource effort for acceptance of new or revised

[[Page 35197]]

licensee or vendor analysis methods. Therefore, it is anticipated that 
this topic will be addressed at a future date.
    Comment: APS considers an appropriate set of benchmark data to 
include other acknowledged industry standard data or criteria.
    Response: The examples of appropriate benchmark data has been 
expanded to include APS' suggestions.
    Comment: APS suggests that Section 2.5 be revised to allow a 
provision for evaluating vendor updates and implementing those updates, 
if applicable.
    Response: The proposed rewording has been incorporated into Section 
2.5.

Centerior Energy

    Comment: The guidance should be explicit enough to allow for 
utilities to reference topical reports submitted by non-NSSS vendors.
    Response: Utilities have been added to the example of organizations 
that develop methods.
    Comment: The proposed guidance should be sufficiently flexible to 
allow substitution of computer codes within an approved analytical 
methodology.
    Response: The Application Procedures have been modified to allow 
this, but should contain proper controls to preclude misapplications or 
inappropriate use of an application.
    Comment: NRC should maintain a listing of the codes or methods it 
has approved.
    Response: The NRC is currently developing a data base of approved 
codes as a separate action.
    Comment: NRC should define the point at which reapproval of updates 
is necessary.
    Response: What constitutes a significant code or methodology update 
that must be reviewed by the NRC is too complex a topic to fully 
address in generic terms at this time. However, as mentioned in the 
Federal Register notice (60 FR 54712; October 25, 1995), the NRC is 
also investigating modified procedures for reducing the resource effort 
for acceptance of new or revised licensee or vendor analysis methods. 
Therefore, it is anticipated that this topic will be addressed at a 
future date.

    For the Nuclear Regulatory Commission.

    Dated at Rockville, Maryland, this 24th day of June, 1999.
James E. Lyons,
Deputy Chief, Events Assessment, Generic Communications and Non-Power 
Reactors Branch, Division of Regulatory Improvement Programs.
[FR Doc. 99-16597 Filed 6-29-99; 8:45 am]
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