ML20059A516
| ML20059A516 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf, Arkansas Nuclear, Waterford  |
| Issue date: | 10/21/1993 |
| From: | Dewease J ENTERGY OPERATIONS, INC. |
| To: | Murley NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| CNRO-93-00032, CNRO-93-32, NUDOCS 9310260359 | |
| Download: ML20059A516 (26) | |
Text
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-~~ Entorgy c"9'u o ir "aa
'"c-r Operations October 21,1993 U.S. Nuclear Regulatory Commission Mail Station P1-137 Washington, D.C. 20555 Attention:
Document Control Desk
SUBJECT:
Proposed Alternative to 10CFR 50.55a(f) and (g),10-Year Inservice inspection & Inservice Testing Update Arkansas Nuclear One Units 1 & 2 Docket Nos. 50-313 & 50-368 License Nos. DPR-51 & NPF-6 Grand Gulf Nuclear Station Unit 1 Docket No. 50416 License No. NPF-29 Waterford 3 Steam Electric Station Docket No. 50-382 License No. NPF-38 CNRO-93/00032
Dear Dr. Murley:
10CFR50.55a(a)(3) allows you to authorize alternatives to the requirements of 10CFR50.55a paragraphs (f) and (g) (i.e., automatic licensee endorsement of the latest edition of the Code every 10 years) provided certain standards are met.
Entergy Operations, Inc. is submitting by this letter a proposed alternative to the requirements of 10CFR50.55a(f)(4)(ii), (f)(4)(iv), (g)(4)(ii), and (g)(4)(iv) in accordance with 10CFR 50.55a (a)(3). The proposed alternative would substitute existing regulatory controls and a licensee evaluation process in lieu of the current automatic ten year update of inservice examinations and tests to the latest approved edition and addenda of the ASME Code.
E 690 3 9310260359 971021 F
PDR ADOCK 0500o313 F
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Proposed Alternative to 10CFR50.55a(f) and (g),10-year ISI & IST Update October 21,1993 CNRO-93/00032 Page 2 of 3 The attachment to this letter provides a detailed description of the basis for the proposed alternative. Based on the guidelines in 10CFR50.55a(a)(3), Entergy Operations has concluded the proposed alternative is at least equivalent to the intent l
of 10CFR50.55a and will provide safety benefits beyond those achievable by the I
present rule. Consequently, Entergy Operations requests that the proposed alternative be authorized for use throughout the operating lifetime of Arkansas Nuclear One Units 1 & 2, Grand Gulf Nuclear Station, and Waterford 3 Steam Electric Station.
I We understand that our request is novel in a number of respects; for instance, we are 1
unaware of previous requests under the terms of 10CFR50.55a(a)(3), and the
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adoption of later ASME Code editions / addenda has come to be viewed as a traditional I
part of nuclear regulation. In the spirit of your cost beneficiallicensing activities (CBLA) program, we believe that review of this request may prompt a reconsideration of selected regulatory policy and processes. We would be happy to meet with you or your staff to assist in this process.
l We had previously agreed to provide the NRC with a priority ranking of Entergy i
Operations CBLA requests. The prioritization for the 10CFP50.55a alternative is a function of scheduled plant activities. In this case, Arkansas Nuclear One, Unit 1 and Grand Gulf Nuclear Station will begin devoting signifi<; ant resources to their 10 year update efforts at the beginning of 1994. To suppor: this schedule, we request your review and approval by the end of January,1994.
Should you have questions or comments, please contact me or George Zinke at (601) 437-2459.
Yours truly,
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V G 4(QLA&C J. G. Dewease JGD/baa attachment: Alternative to 10CFR50.55a(f) and (g) cc:
(See Next Page)
o Proposed Alternative to 10CFR50.55a(f) and (g),10-year ISI & IST Update October 21,1993 CNRO-93/00032 Page 3 of 3 cc:(w/a)
Mr. T. W. Alexion Mr. R. P. Barkhurst I
Mr. R. H. Bernhard Mr. R. B. Bevan, Jr.
Mr. J. L. Blount Mr. J. L. Colvin Mr. S. D. Ebneter Mr. E. J. Ford Mr. C. R. Hutchinson Mr. H. W. Keiser Mr. L. D. Marsh Mr. R. B. McGehee Mr. J. L. Milhoan Mr. P. W. O'Connor Mr. N. S. Reynolds Ms. L. J. Smith Mr. F. W. Titus Mr. D. L. Wigginton l
Mr. J. W. Yelverton Central File (GGNS)
DCC (ANO)
Records Center (W-3) i Corporate File [20]
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1 Attachm:nt 1
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CNRO-93/00032 Page 1 of 23 i
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Proposed Alternative to 10CFR 50.55a(f) and (g),
10-Year Inservice Inspection & Inservice Testing ASME Code Edition / Addenda Update t
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CNRO-93/00032 Page 2 of 23 I
A. INTRODUCTION Over the past several years, the NRC has devoted substantial resources to identification and analysis of the negative effects of regulation, culminating in a number of related initiatives such as the Cost Beneficial Licensing Action (CBLA) pilot program, the Regulatory Review Group, and the Elimination of Requirements Marginal to Safety Program.
One common thread in these efforts is the recognition that, in some cases, regulations are overly prescriptive resulting in the expenditure of unnecessary resources that could better be applied to more safety significant areas.
Likewise, in some cases, duplicate and/or similar regulatory processes may impose NRC and licensee burdens without a corresponding increase in public health and safety.
Such is the case for the 10CFR50.55a requirement to adopt, every 10 years, the ASME Ccda Section XI editions and addenda most recently approved by the NRC. Under the NRC's CBLA pilot program, Entergy Operations proposes to replace this requirement with a requirement to implement only those updated
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Code sections that provide a substantial increase in safety.
The net result of the proposed change, as discussed below, will be a significant reduction in Entergy Operations' cost (e.g., on the order of 5 3 M over the life of Grand Gulf), more focused attention on safety / risk significant areas of the plant with a corresponding safety benefit, and reduced burden on NRC staff resources allowing them to be redirected to more safety significant areas.
The alternative we propose recognizes, among other things, the changing nature of the nuclear industry and its regulation. Although worthwhile in the early 1970s, during the 20 years that have elapsed since 10CFR50.55a was adopted we have seen a number of industry and regulatory advances thr,t serve to minimize the value of the periodic update of ASME Code requirements for operating plants and, in some cases, raise concerns that attention to j
periodic ASME Code updates may inhibit implementation of more safety significant improvements. Some of the most notable advances include:
I A significantly increased capability and sophistication in understanding, identifying and addressing those aspects of design and operation that contribute to overall plant risk. The NRC and the i
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Anachment 1 CNRO-93/00032 Page 3 of 23 industry have tools available today that were little more than concepts when 10CFR50.55a was framed. The use of probabilistic risk assessment, improved thermal-hydraulic and dose calculation models, more reliable design basis documentation, and the like have contributed immeasurably tc the ability to precisely focus on the important factors in design and operation. The broad approach taken by 10CFR50.55a to upgrade standards regardless of the system or component to which they're applied, while necessary at the time, is no longer essential nor desirable.
Routine use of additional regulatory mechanisms such as the Backfit Rule that serves the same purpose as a periodic ASME Codo update.
When the NRC determines that a particular requirement is necessary due to its substantial safety benefit, that requirement is imeosed upon appropriate licensees through rulemaking or other mechanism;., moderated by the Backfit Rule. This approach ensures that not only is a substantial safety benefit to be gained, but that the cost of the new requirement is comparable to the benefit achieved. Although there was a Backfit Rule of sorts in existence when 10CFR50.55a was adopted, it was seldom utilized until backfit reform was implemented in the mid-to late 1980s. It is now the NRC's practice to address separately through rulemaking and other means (e.g. generic communications) those portions of the ASME Code upgrades i
which meet the test of the Backfit Rule. In this sense, the provisions of 10CFR50.55a are redundant in requiring the adoption of significant Code upgrades, and excessive in mandating the remainder of the Code upgrades.
A recognition on the part of the industry and the regulators that scarce resources spent on less safety significant areas means tht some areas of plant ope. ration or design that may be more safetj significant must pay the cost in reduced resources. The genesis of Dr.
Murley's cost berseficial licensing actions pilot program, the Regulatory Review Group and other recent NRC initiatives, as well as the renewed industry focus on the need to balance cost and safety benefit, is the clearer understanding that resources are limited and must be wisely invested in those activities that are most safety significant. Broadly focused regulations such as 10CFR50.55a, which make no distinction between the important and the trivial, ultimately degrade safety by robbing resources better used elsewhere. Conversely, eliminating the cumulative effect of programs and requirements which are not clearly focused through substituting alternative measures such as performance-and risk-based approaches will improve safety.
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CNRO-93/00032 Page 4 of 23 i
l The following sections expand upon these and other bases in support of y
Entergy Operations' proposed alternative to periodic ASME code update requirements of 10CFR50.55a.
B. BACKGROUND A review of the regulatory history and ASME Code update process is helpfulin understanding the propose <. change.
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10CFR50.55a Selected portions of 10CFR50.55a are relevant to our discussion.
Section 50.55a of the NRC regulations requires that nuclear power plant owners construct Class 1,2, and 3 components in accordance with Division 1 rules of Section Ill, " Rules for Construction of Nuclear Power Plant Components," of the American Society of Mechanical Engineers Boiler and Pressure Vessei Code (ASME Code). Once constructed,10CFR50.55a i
requires licensees to provide for and perform inservice inspection (ISI) and inservice testing (IST) in accordance with Division 1 rules of Section XI, " Rules for Inservice inspection of Nuclear Power Plant Components," of the ASME Code. These requirements, which are not affected by the proposed change, have been included in the Code of Federal Regulations since shortly after publication of Section ill and Section XI of the ASME Code in 1971.
The preamble to the August 24,1972 final rule amending 10CFR50.55a (37 FR 17021) states that "as new or amended editions of applicable codes, code
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cases, or addenda are issued, the Commission will review them and amend the provisions of 10CFR50.55a... as appropriate." This regulatory mandate i
is contained in an automatic endorsement process described in 10CFR50.55a(f)(4)(ii) and (g)(4)(ii) whict, require that licensees revise their inservice examination and inservice testing programs every ten years to comply with the requirements of the latest edition and addenda of Section XI, Division 1, endorsed by the NRC 12 months prior to the start of the next 120-l month inspection interval. Entergy Operations is proposing equivalent attematives to these positions of 10CFR50.55a as well as the related provisions of 10CFR50.55a(f)(4)(iv) and (g)(4)(iv) which prohibit licensee j
incorporation of subsequent NRC-endorsed editions and addenda of Section XI prior to the beginning of the next 120-month inspection interval, except as specifically approved by the Commission on a case-by-case basis.
if a licensee determines that conformance with certain code requirements is h
l CNRO-93/00032 Page 5 of 23 impractical for its facility, the licensee submits information to support its determination and requests relief from the requirements The Commission may grant or deny relief, and/or impose alternative requirements in accordance i
with 10CFR50.55a(f)(6) and (g)(6).
l Finally,10CFR50.55a(a)(3) allows the Director of the Office of Nuclear Reactor Regulation to authorize alternatives to the requirements of 10CFR50.55a paragraphs (t) and (g) (i.e., automatic licensee endorsement of the latest edition of the Code every 10 years) provided certain standards are met. Entergy Operations is proposing such an alternative to the automatic endorsement process.
t Before discussing the NRC process for endorsement of updated ASME Code editions and/or addenda, it is necessary to briefly review the ASME Code process.
ASME Code Change Process In general, revisions are made to improve the ASME Code by providing more detailed rules (new and/or revised rules) where experience indicates greater guidance is necessary, or relaxing the rules where experience shows equivalent operational safety can be maintained with a reduced burden on the licensees.
Tne ASME puolishes a new edition of the Code every three years. In the past, new addenda have been published for Section XI, Division 1, every six months. Since 1986, new addenda have been published once a year. The '
revisions are the result of consensus participants meeting several times a year i
for the purpose ofimproving the existing rules.
i The revisions take into account the many lessons learned in a specific area since the development of a particular Code rule. These revisions generally fall into three categories: (i) technical revisions that incorporate new rules in technical areas not previously addressed by the Code; (ii) technical revisions to existing rules; and (iii) editorial revisions. When a technical revision is made, it may make the existing set of rules more or less restrictive, or may simply clarify the existing rule without changing its intent, or may add new rules.- There are numerous revisions in each addenda. In general, technical revisions are made to improve the ASME Code by providing more detailed rules where experience indicates greater guidance is necessary, or relaxing the rules where experience shows equivalent operational safety can be maintained with a reduced burden on the licensee.
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The ASME Code is developed using the consensus procedures of the American Society of Mechanical Engineers (ASME). This process attempts to ensure that participation in ASME Code development is open to all persons l
and organizations that might reasonably be expected to be directly and materially affected by the activity, and ensures that such persons and organizations have the opportunity for fair and equitable participation without dominance by any single interest.
Consensus is established when substantial agreement has been achieved by the interests involved. Consensus requires that all views and objections be considered and that a concerted effort be made toward resolution. While the consensus process ensures that the various technical interests (e.g., utility, manufacturing, insurance, regulatory) are represented on the standards i
development committees and their viewpoints are considered in the standards writing process, it does not have a reliable mechanism to ensure that the implementation costs associated with proposed changes are commensurate with the expected benefit, nor is there any threshold for determining a minimal level of benefit necessary to proceed with a change. This is in sharp contrast to the rigorous controls of the Backfit Rule, which will be discussed more fully later.
ASME Code proposed revisions are published for public comment in the i
ASME Mechanical Engineering and ANSI Reporter publications prior to being i
submitted for final ASME and ANSI approval. Adverse public comments are i
referred to the appropriate ASME technical committee for resolution.
NRC Endorsement of ASME Code Changes The mechanism for NRC endorsement, which has been used since the first endorsement in 1971, has been to incorporate by reference Section Ill, Division 1, and Section XI Division 1, of the ASME Code into 10CFR50.55a.
The regulation thus amended identifies which editions and addenda of the ASME Code have been approved by the NRC for use.
i 11 has been a continuing policy of the Commission to periodically update this l
section of the regulations (i.e.,10CFR50.55a) to keep the ASME Code references current. For example,1992 rulemaking incorporated by reference the 1986 Addenda,1987 Addenda,1988 Addenda, and 1989 Edition of Section XI, Division 1, of the Code, with two specified exceptions. The ASME Section XI revisions generally serve to make the rules for the testing of pumps and valves consistent with regulatory positions, and generally improve the j
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I CNRO-93/00032 Page 7 of 23 procedures for the detection, analysis and repair of flaws in the reactor vessel and other components, and their supports. In those cases where an item in the ASME Code was m.t consistent with an NRC staff position, an exception has been taken to ntsing that portion of the Code or supplementary criteria have been incorporated to make the item consistent with the staff position.
I While the NRC makes fairly frequent ASME Code endorsements through rulemaking, licensee incorporation of those endorsements into their ISI/IST programs is a function of neither the safety significance of the Code change nor the frequency of rulemaking. Rather, the likelihood of a licensee adopting a particular endorsement is only dependent upon the length of time between l
NRC endorsement and expiration of periodic 10 year intervals based on the l
date of receipt of an operating license.
The combined effects of the ASME Code update process, the NRC's endorsement process, and the extended adoption periods reauired by 10CFR50.55a (i.e., early adoption is not allowed without NRC approval) i together conspire to stretch out licensee adoption of any given ASME Code change to something approaching 20 years on average (from conception to i
implementation). Allowing half the licensed plant lifetime to expire prior to implementation serves to emphasize that there is no substantial safety benefit for the vast majority of ASME Code changes.
Rejationshio to the Backfit Rule i
Historically, the Commission has not evaluated changes to the ASME Code in i
accordance with 10CFR50.109 (
Reference:
February,1992 regulatory analysis for Final Rule to Amend 10CFR50.55a; Enclosure 2, Page 2-17 and Appendix B, Page 3C-12).
The Office of the General Counsel has provided the opinion that amendments to 10CFR50.55a that simply update the existing reference to edition and addenda of Section XI of the ASME Code and do not imoose limitations and modifications should not be subjected to the backfit provisions of 10CFR50.109. Their rationale is that, (1) licensees are fully aware that
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10CFR50.55a requires that they update their inservice inspection program every 10 years to the latest edition and addenda of Section XI that were incorporated by reference in 10CFR50.55a twelve months prior to the start of the next inspection interval, and (2) endorsing and updating references to the ASME Code, a national consensus standard developed by participants (including the NRC) with broad and varied interests, is consistent with both the intent and spirit of the backfit rule.
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CNRO-93/00032
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Should the NRC feel, in the interest of safety, that the ASME Code updates are unacceptable, it can and has taken exception in 10CFR50.55a to the rules provided in the ASME Code. Likewise, should the NRC feel, in the interest of safety, that the new addenda / editions of the Code contain items that provide for a substantial increase in the overall protection of the public health and safety or the common defense and security, it can and has taken action to require implementation on a schedule that is appropriate considering the
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safety significance. This option is not used often, but is available to the NRC when necessary. For example, the NRC has required licensees to implement augmented inspections of all reactor vessel shell welds after concluding that the backfit would result in a substantialincrease in the overall protection of the public health and safety, and that the cost of implementation was justified in view of the increased protection. The NRC imposed this requirement through 10CFR50.55a rulemaking by performing a cost / benefit analysis in accordance with the Backfit Rule (10CFR50.109).
C.
COMMENTARY ON SAFETY BENEFIT AND THE BACKFIT RULE i
Regulatory requirements are being increasingly compared to a de facto standard to test their viability:
Does the requirement ensure that the costs of implementation are balanced by the safety benefits to be received?
This standard acknowledges that licensee resources are not unlimited. When personnel and money resources are dedicated to resolving problems or 1
implementing solutions for issues of relatively low safety significance, such resources are now unavailable to be applied against more safety significant issues. In the extreme, regulatory requirements that are not well focused on significant safety priorities serve to degrade safety, it is this concept that makes up the essence of the Backfit Rule, the
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NRC's burden reduction initiatives and Entergy Operations' request for alternative measures to 10CFR50.55a.
In this light, it is worthwhile to examine the " benefit" side (often expressed in terms of risk reduction) of the cost / benefit equation for the periodic update requirements of 10CFR50.55a. Cost will be discussed later.
Evaluating the benefit of the endorsement of various new or amended editions of the Code is a difficult task considering the magnitude of line item changes q
t Attachm::nt 1 CNRO-93/00032 Page 9 of 23 typically involved. The review of the 199210CFR50.55a rule change provides a good example of the complexity. The final rule incorporated by reference the 1986 Addenda,1987 Addenda,1988 Addenda, and 1989 Edition of Section XI, Division 1, of the Code, with two specified exceptions. The regulatory analysis grouped the Section XI Code changes into 52 items for discussion purpose.
The changes were characterized as follows:
22 editorial changes 16 technical changes which increased licensee net burden 13 technical changes which decreased licensee net burden 1 technical change which did not change licensee net burden l
Several of the 52 items were further subdivided in the analysis with the sub-items being characterized as to which ones increased or decreased burden.
Many of the " decreased net burden" items also contained numerous
" increased burden" sub items. The potential risk reduction for the line items was also discussed. Typical risk reduction characterizations for the increased burden items included:
"should reduce the risk of structural failure"
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" risk should be somewhat reduced" l
"will reuuce the risk to the public, but the change in risk is not quantifiable" "some decrease due to more conservative evaluation procedures" l
"a potential small decrease" "no change in risk"
" slight reduction in risk is anticipated" l
"may reduce risk slightly" "no change in risk is anticipated" L
"may be a slight decrease in risk" Only one of the increased burden items was positively identified as having an effect on risk (i.e., "will reduce the risk to the public, but the change in risk is not quantifiable"). Because the Commission felt strongly that this one item would reduce risk, it was singled out as an exception to the automatic 10-year code endorsement process, and imposed upon licensees on an accelerated -
schedule via rulemaking. Backfit analysis was performed on this one line item (reactor vessel shell welds augmented examination) in accordance with 10CFR50.109. None of the risk characterizations of the other items were clearly tied to core damaae frequency or probability of offsite radiological release. Some of the " risk" characterizations were subjectively tied to component probability of failure. None of the risk characterizations individually 4
L CNRO-93/00032 Page 10 of 23 or collectively indicated that a substantial increase in the overall protection of the pub!!c health and safety was likely to occur.
Generalized boilerplate statements about increases in safety have been contained in the regulatory analysis for the various amendments to 10CFR50.55a which update the references to the ASME Code:
"The revisions generally improve plant safety by incorporating new rules to cover areas not previously addressed, or by revising the rules consistent with experience to reduce the number of areas where the
^ ode has been found to be impractical, inadequate, or insufficiently Ae v ' "
"There will be a substantial increase in safety through the endorsement of the later addenda and edition, because it will be these addenda and edition that will be used in subsequent inservice inspection programs.
Obsolete requirements will not continue to be promulgated from inspection interval to inspection interval."
Neither of these characterizations were supported by the detailed analysis of the changes. Additionally they imply that "subsbntial increase in safety" inherently results from new rules and regulations simply because they will be implemented by licensees.
The cumulative result of the 1992 rulemaking was that the only Code change perceived by the Commission to have the potential for substantialincrease in the overall protection of public health and safety was extracted and imposed upon licensees in accordance with the Backfit process of 10CFR50.109. The remaining changes (i.e., backfits) to the Code that increased licensee burden were of minor safety significance but were imposed anyway without regard for the cost of implementation.
Many of these changes can be justifiably called " worthwhile." However, it is not the function of the CommissKin to impose upon licensees new requirements that are "worthwhik. " Any group of people, including Code committees, industry groups, and the Commission can conceive of
" worthwhile" things which they think others should be required to do. The problem in using such an approach, however, is that the costs of implementing
" worthwhile" requirements must be compared to some standard to ensure that the Inost " worthwhile" improvements are implemented. Neither the consensus approach of the ASME Code committees nor the NRC's periodic endorsement process provide this disciplined approach.
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Page 11 of 23 On the other hand, the Backfit Rule with its " substantial increase" criterion and insistence upon balancing cost and safety benefit imposes the necessary discipline upon the Commission so that the overall goal of protection of the public health and safety is not undermined by well-meaning imposition of new
" worthwhile" requirements. Avoiding this disciplined approach in processing
" amendments to 10CFR50.55a that simply update the existing reference to edition and addenda of Section XI of the ASME Code"is not consistent with either the intent or spirit of the Backfit Rule, does not provide for the protection of the public health and safety, and does impose an undue burden on licensees which serves to reduce resources available for more safety significant activities.
Licensees have historically objected to this policy employed by 10CFR50.55a claiming that endorsement of later editions and addenda is a backfit that should be justified in accordance with 10CFR50.109. The Commission has consistently responded by quoting the General Counsel opinion previously discussed. One of the difficulties licensees have had with this Commission policy is that updating the reference to edition and addenda of Section XI of the ASME Code usually dnes impose limitations and modifications to the procedures required to operate each facility. Being aware that new editions and addenda of the Code are required to be endorsed at the beginning of each 10-year inspection interval does not negate the frustration of allocating resources to modifications that do not provide a substantialincrease in the overall protection of the public health and safety. Although the ASME Code consensus process considers cost and benefit and attempts to provide a reasonable balance, the criteria of 10CFR50.109(a)(3) are not applied; i.e.
I "Except as provided in paragraph (a)(4) of this section, the Commission shall require the backfitting of a facility only when it determines, based on the analysis described in paragraph (c) of this section, that there is a substantial i
increase in the overall protection of the public health and safety or the common defense and security to be derived from the backfit and that the direct and indirect costs of implemer.i_%on for that facility are justified in view of this increased protection."
When the " substantial increase" criterion was promulgated in its present form in 1985, the Commission said:
"[s]ubstantial" means "important or significant in a large amount, extent, or degree." Under such a standard the Commission would not ordinarily i
expect that safety improvements would be required as backfits that result in an insignificant or small benefit to public health and safety...
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9' CNRO-93/00032 Page 12 of 23 regardless of costs. On the other hand, the standard is not intended to be interpreted in a manner that would result in disapproval of worthwhile safety or security improvements having costs that are justified in view of the increased protection that would be provided.
The alternatives to 10CFR50.55a proposed by Entergy Operations will implement the " substantial increase" and safety / cost balancing provisions of the Backfit Rule as discussed below.
D. DESCRIPTION OF PROPOSED ALTERNATIVE 10CFR50.55a(a)(3) allows the Director of the Office of Nuclear Reactor Regulation to authorize alternatives to the requirements of 10CFR50.55a paragraphs (f) and (g) (i.e., automatic licensee endorsement of the latest edition of the Code every 10 years) provided certain standards are met.
Entergy Operations, Inc. (Entergy) hereby requests authorization of the following alternative to the requirements of 10CFR50.55a paragraphs (f)(4)(ii),
(f)(4)(iv), (g)(4)(ii), and (g)(4)(iv):
Inservice examinations of components, inservice tests to verify operational readiness of pumps and valves whose function is required for safety, and system pressure tests, conducted during successive 120-month inspection intervals will comply with the requirements of the latest edition and addenda of the Code committed to by the licensee as of the approval date of this proposed alternative, subject to the limitations and modifications listed in paragraph (b) of 10CFR50.55a and subject to the following paragraphs.
In lieu of the above referenced Code edition and addenda, Inservice examinations of components, inservice tests to verify operational readiness of pumps and valves whose function is required for safety, and system pressure tests, conducted during successive 120-month inspection intervals will comply with the requirements of the latest edition and addenda of the Code incorporated by reference in paragraph (b) of 10CFR50.55a 12 months prior to the start of the 120-month inspection interval, subject to the limitations and modifications listed in paragraph (b) of 10CFR50.55a, for which there is a substantial increase in the overall protection of the public health and safety or the common defense and security to be derived from the change and for which the direct and indirect costs of implementation are justified in view of this increased protection.
CNRO-93/00032 Page 13 of 23 Insentice examinations of components, tests of pumps and valves, and system pressure tests, may meet the requirements set forth in subsequent editions and addenda that are incorporated by reference in paragraph (b) of 10CFR50.55a, subject to the limitations and modifications listed in 3
paragraph (b) of 10CFR50.55a. Portions of editions or addenda may be used provided that all related requirements of the respective editions or addenda are met.
The proposed alternative would work in the following manner. The development and review of editions and addenda of the ASME Code by the industry and the Code committees would not be affected. Likewise the review by the NRC of editions and addenda would not be affected. Following the rulemaking process in which the new editions and addenda are incorporated by reference into 10CFR50.55a, each licensee of Entergy Operations would have several options:
(1) It could choose to comply with the requirements of the la'.est edition and addenda of the Code incorporated by reference in paragrapn (b) of 10CFR50.55a 12 months prior to the start of the 120-month inspection interval, subject to the limitations and modifications listed in paragraph (b) of 10CFR50.55a. This option allows the licensee to continue the same process endorsed by 10CFR.
(2) It could choose to comply with the requiremerits of the latest edition and addenda of the Code (or portions thereof) incorporated by reference in paragraph (b) of 10CFR50.55a at any time following posting of the final rule.
This option would require no further approvals by the Commission. This option would ensure that all related requirements of the respective editions and addenda were met if only portions of the editions and/or addenda were to be implemented. "Related" would be defined to encompass those requirements which, if not implemented in combination with each other, could actually result in a decrease in the protection of public health and safety which had not been reviewed or approved by the Commission. For example, if a Code change which reduced burden was solely justified by the Commission as being acceptable (with regard to its affect on protection of public health and safety) due to its relationship with a new requirement which increased burden, the licensee could not choose to implement the burden reduction change without also implementing the burden increase item. There would be no requirement to implement any Code changes which had not been identified by the Commission as providing a substantial
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increase in the overall protection of the public health and safety. There y
CNRO-93/00032 Page 14 of 23 would be no requirement to evaluate generalizations about potential safety increases contained in the regulatory analyses which are not referenced to j
specific Code changes or combinations of changes.
(3) It could choose to comply with the requirements of the edition and addenda of the Code committed to on the approval date of this proposed alternative, subject to the limitations and modifications listed in paragraph (b) of 10CFR50.55a This option would essentially retain the same Code reference for the duration of the licensee operating license. The licensee would still be required to implement those portions of the later editions and addenda which the Commission had determined to provide a substantial increase in the overall protection of the public health and safety since those exceptions would continue to be specified in paragraph (b) of -
10CFR50.55a. The schedule for implementation of such items would be in accordance with paragraph (b) of 10CFR50.55a. The licensee would still be required to evaluate the regulatory analyses of the latest edition and addenda of the Code incorporated by reference in paragraph (b) of 10CFR50.55a 12 months prior to the start of the 120-month inspection interval. This review would ensure that changes which provide a substantial increase in the overall protection of the public health and safety due to plant-unique design were identified and incorporated. There would be no requirement to evaluate generalizations about potential safety increases contained in the regulatory analyses which are not referenced to specific Code changes or specific combinations of changes.
i E. JUSTIFICATION FOR THE PROPOSED ALTERNATIVE i
10CFR50.55a(a)(3) allows the Director of the Office of Nuclear Reactor Regulation to authorize alternatives to the requirements of 10CFR50.55a paragraphs (f) and (g) provided certain standards are met. These are (i) the proposed alternatives would provide an acceptable level of quality and safety, or (ii) compliance with the specified requirements of this section would result in hardship or unusual difficulties without a compensating increase in the level of
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quality and safety.
Entergy Operations has evaluated the proposed alternative in accordance with the above criteria. The proposed alternative meets requirements of 10CFR50.55a(a)(3)(i) and should therefore be granted. Entergy Operations presents the following analyses in support of this proposed alternativo application:
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1.
10CFR50.55a(a)(3)(i)- Altemative Authorbation Criteria The orocosed alternative would orovide an acceotable level of auality and safety Tne Code edition and addenda for the current 120-month inspection intervals establish a base level of quality and safety which is currently acceptable to the Commission. The proposed alternative would -
maintain that level, assuming no future updates to later Code editions.
I Later NRC approved Code editions and addenda (or portions thereof) would be adopted provided a substantialincrease in safety would result and was cost justified. Later NRC approved Code editions and addenda (or portions thereof) which are safety neutral could be adopted if the licensee desired to. Adoption of safety neutral Code changes would no longer be imposed upon the licensee as a requirement.
The NRC process for review and approval of Code editions and addenda identifies which changes provide a substantial increase in safety. Since the method used by the Commission to endorse later editions and addenda allows licensees up to eleven years to adopt the changes and can allow up to twenty years to implement the change (depending on the specific type change), changes which provide a substantial increase in
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safety have been imposed using alternative processes. Separate rulemaking, Generic Letters, and Bulletins are typical processes the Commission has used to require licensees to respond to significant issues on a schedule appropriate to the significance of the issue. These processes appropriately invoke 10CFR50.109 cost / benefit analysis (except when the change involves regulatory complian.ce instead of backfit) to justify the proposed backfit. The 10CFR50.109 cost / benefit ana!ysis provides a more rigorous analyses (with established criteria) than was considered during the ASME Code Committee development process.
l Likewise the licensee and public processes for review and response to rulemaking, Generic Letters, and Bulletins is well established. Overall the processes mentioned establish a framework which ensures that acceptable levels of quality and safety are maintained.
The " automatic Code endorsement" process as currently implemented tends to undermine processes subject to 10CFR50.109 in that it requires utilities to allocate resources to facility / procedure modifications which do not routinely provide substantial increases to public health and safety.
Given limited resources, this removes from the licensee the ability to allocate its resources in a responsible manner.10CFR50.55a provides a l
process to request relief from burdensome requirements, but the relief l
process itself demands resources. Although the resources required to t
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CNRO-93/00032 Page 16 of 23 obtain this approval may not be significant, it is the accumulation of seemingly small burdens which eventually create a large burden. The alternative proposed in this submittal would make use of those Commission processes which already ensure an acceptable level of quality and safety (e.g. rulemaking, Generic Letters, Bulletins, 10CFR50.109 Backfit Analyses), combined with an additionallicensee 1
evaluation to determine the safety impact of a potential change.
i Specifically, the level of quality and safety at Entergy Operations licensed facilities would be maintained because:
(a) The current Code end addenda (and approved relief requests) established a level of qua;ity and safety which was acceptable to the Commission.
(b) It is clear that Commission-approved changes to the Code editions and addenda incorporated by reference into 10CFR50.55a do not provide a substantial increase to public health and safety since 10CFR50.55a currently prohibits licensees from endorsing and l
implementing such changes earlier than the scheduled 10-year update (unless the licensee voluntarily requests Commission approval to do -
so). Changes (i.e. backfits) to the Code editions and addenda which do provide a substantial increase to public health and safety have been, and would continue to be, imposed upon licensees by the Commission through processes separate from the update of Code j
references in 10CFR50.55a (e.g. specific rulemaking, Generic Letters, Bulletins). The processes used by the Commission to impose such backfits more aptly ensure public health and safety since backfits which substantially increase public health and safety should not be j
delayed for on the order of twenty years prior to implementation by licensees. Therefore the proposed alternative does not affect the licensee implementation of any Commission-approved changes to the Code editions or addenda which provide a substantialincrease to public health and safety.
(c) The proposed alternative would allow Entergy Operations licensees to implement Commission-approved changes to the Code editions and addenda incorporated by reference into 10CFR50.55a
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prior to the start of the next 10-year inspection interval without requiring separate Commission approval to do so. In addition to reducing Commission burden (licensee burden is relatively low), this alternative could potentially increase public health and safety since
CNRO-93/00032 Page 17 of 23 such changes would more likely be implemented earlier than currently allowed. It is noted that any increase to public health and safety would not be substantial since such changes are processed by the Commission separate from the " incorporation by reference."
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(d) Changes to the Entergy Operations inservice inspection and i
inservice Testing Programs and/or implementing procedures are accomplished in accordance with 10CFR50.59 and therefore the Entergy Operations Safety Evaluation processes also provide assurance that an acceptable level of quality and safety is ma:ntained.
(e) 10CFR50.55a(f)(4)(iv) and (g)(4)(iv) state in part that " portions of
^I additions or addenda may be used provided that all related requirements of the respective editions or addenda are met." The proposed alternative retains this requirement. It would be the responsibility of Entergy Operations licensees to ensure that when only portions of new Commission-approved editions and addenda were incorporated, that this requirement was met. Entergy Operations engineering expertise coupled with the regulatory analyses associated with any given rulemaking updating the Code references permit the licensee to reasonably make this judgment. Entergy Operations participates in ASME Code committees and maintains technical expertise in Code issues. Likewise the regulatory analyses are l
sufficiently detailed in expressing the Commission's opinion on the interrelationships of any changes to the Code editions and addenda.
Therefore the proposed alternative would provide an acceptable level of quality and safety.
2.
The proposed alternative would allow Entergy Operations to evaluate updated editions and addenda to the Code consistently with all other proposed modifications to plant structures, systems, equipment, procedures, programs and processes.
This change would potentially allow more resources to be allocated to efforts which substantially improve the safety of the plant and are cost justified. Code changes which represent reduced burden with an equivalent operational safety (as determined from the regulatory analysis) 3" could be implemented with no further analysis. Code changes which represent increased burden or no change in burden could either be implemented with no further analysis or be implemented if it were determined that a change would result in a substantial safety benefit and a i
cost / benefit analysis indicated a cost-justified increase in the overall I
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f
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Attachm:nt 1 CNRO-93/00032 Page 18 of 23 protection of the public health and safety would result. Records of licensee determinations of substantial safety benefit and cost / benefit
.j analyses used to justify non-implementation would be maintained as permanent plant records. Documentation of the Code of record would be
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maintained with the 10-year Plan documentation.
i 3.
ASME Section XI, IWA-1400 states the responsibilities of the owner include " preparation of plans and schedules and filing of these plans and schedules with enforcement and regulatory authorities having jurisdiction at the plant site." Although 10CFR50.55a does not require any such filing, licensees have traditionally been obliged to send their 10-year plans to the Commission. The requirement for Commission approval of licensee endorsement of later Code editions has generally been accomplished by including those requests in the 10-year plan submittals. Licensees often submit revisions of their 10-year plans during the 10-year interval, thus meeting the " requirements" of IWA-1400 and 10CFR50.55a.
By replacing the requirement to obtain additional and separate NRC review and approval to implement portions of later NRC-approved Code editions and addenda prior to the beginning of the next 10-year inspection period, burden can be reduced for both the licensee and the' NRC.
Submittal of the 10-year plans to the Commission, subsequent review / approval of the plans, and subsequent review / approval of endorsement of NRC-approved Code editions and addenda are process steps which do not appear to add value or enhance safety and are probably more efficiently handled through an audit approach. Deviations from NRC-approved Code editions and addenda already adopted by the i
licensee would continue to be subject to Commission approval through the relief request process described in 10CFR50.55a.
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4.
The requested alternative to allow use of later NRC approved editions (or portions thereof) of Section XI of the Code than those approved for the current 10 year interval without additional NRC approval is similar to provisions currently acceptable to the Commission for use of Section lll of the Code. These provisions are contained in 10CFR50.55a(c)(3), (d)(2),
and (e)(2) for Class 1,2, and 3 comoonents, respectively.
Each of the above identified provisions in 10CFR50.55a allows (with certain restrictions) the use of paragraph NCA-1140 of Section 111 of the 1
Code to determine which Code Edition and Addenda to be used for construction of components. Paranraph NCA-1140 requires the owner to establish a specific standard Code Edition and Addenda to be included in I
CNRO-93/00032 Page 19 of 23 design specifications. However, it also allows later Code Editions and Addenda in their entirety to be used for construction of components, or the use of specific provision of later Editions and Addenda, provided that all related requirements are met.
These options in the use of Code Editions and Addenda for Sections ill of the Code are analogous to the proposal by Entergy Operations for options in the use of Section XI Editions and Addenda; i.e., Entergy Operations' alternative would also allow use of later NRC approved Code Editions and Addenda than that approved for the current 10 year interval, in part or entirely, as determined appropriate by each site, without additional NRC approval.
5.
In the Commission policy statement on severe accidents in nuclear power plants issued in August 1985, the Commission concluded, based on j
available information, that existing plants pose no undue risk to the public health and safety and that there is no present basis for immediate action on generic rulemaking or other regulatory requirements for these plants.
However, the Commission did recognize that systematic examinations would be beneficial in identifying plant specific vulnerabilities to severe accidents that could be fixed with cost-beneficialimprovements. Generic Letter 88-20 was issued in November 1988 to satisfy the Commission's desire for systematic examinations.
Performance of the IPE provided insight about and a tool for evaluating the j
effect of potential modifications on public health and safety in terms of core damage frequency and radiation exposure risk. For instance, as a result of the GGNS IPE, the overall core damage frequency was determined and reported to be 1.72E-5/ reactor-year which was well below l
the NRC's proposed subsidiary safety goal of 1.0E-4/ reactor-year. The GGNS IPE submittal also included a cost / benefit analysis method usable for evaluating potential changes. In general, a plant modification is j
considered justified by the Commission when the cost of the modification l
compared to the risk reduction yields a ratio of $1000/ man-rem or less.
-I The typical approach used by the Commission in evaluating proposed new regulatory requirements is to first perform an evaluation of the potential safety benefits of the proposed change. The cost evaluation is only prepared if the safety benefits are determined to be significant. Although I
safety benefits may be characterized either quantitatively or qualitatively, quantitative analysis using probabilistic tools can provide insight on the sensitivity of safety (i.e. core damage frequency and/or public radiation exposure risk) to qualitative improvement-type modifications. It would ' e v
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Page 20 of 23 expected that for changes involving ASME Code edition or addenda to be justified as being required by the Commission, core damage frequency and/or public radiation exposure risk should be substantially improved.
One of the insights gained from the IPE was that seemingly worthwhile changes actually can have very little affect on the overall core damage frequency and/or public radiation exposure risk. For example, the ASME Section XI requirements for pumps and valves (Inservice Testing) generally include requirements on periodic testing 'he purpose of inservice testing of pumps and valves is to asses. th? operational readiness. The goal of this testing is to identify deg. Cation of the pumps and valves so that corrective actions can be taken, minimizing the occurrence of pump and valve failure during actual demands in response to accidents or transients. For changes to the Code to increase public health and safety, they would reasonably need to either reduce the pump and valve failure rates, or decrease pump and valve unavailability (e.g.
decrease the out-of-service time due to testing). Additionally the changes would need to be evaluated in the context of all other regulatory requirements which ensure operational readiness (e.g. Generic Letter 89 1
10 concerning MOVs, Maintenance Rule implementation, etc.). For GGNS, even if the failure rates of every pump and valve were improved by 10%, there would not be a significant reduction in core damage frequency.
In general the type of changes included in new editions and addenda of the Code do not approach the possibility of improving pump and valve availabilities even by 10%. Concerning inservice Inspection (e.g. weld inspections), for changes to the Code to increase public health and safety they would reasonably need to reduce the probability of pipe or pressure vessel failure. Generic failure rates (based on industry data) are so low when compared to active components (pumps and valves) that pipes and vessels were not individually modeled in the IPE. Incremental improvements to inspection requirements will thus have little affect on core damage frequency. For changes to the Code to significantly reduce core damage frequency, they would likely need to be associated with major new understanding about either the probability of failure (e.g. actual major increase in the number of failures) or previously unknown modes of failure.
Improvements to the training of inspectors who conduct non-destructive i
examinations, although possibly worthwhile, will not significantly improve core damage frequency. Although such changes can reasonably be expected to improve the probability of identifying flaws, based on our current engineering judgment, such changes are not expected to have a significant effect on core damage frequency.
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CNRO-93/00032 Page 21 of 23 Although a cost / benefit analysis involving off-site dose release was not performed as part of the ANO-1 and ANO-2 IPE submittals, the GGNS cost / benefit approach and intent apply to the ANO units. Regarding core
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damage frequency, a 10% reduction in the ANO-1 and ANO-2 MOV demand failure rates and pump failure rates was estimated to reduce the ANO-1 Core Damage Frequency (CDF) by about 6% and the ANO-2 CDF by about 5%. Since both the ANO-1 and ANO-2 CDFs are below the 1.0E-04/rx-yr safety goal, these reductions, like those for Grand Gulf, are considered insignificant.
6.
The proposed alternative would allow Entergy Operations to devote resources to evaluating new inspection and testing methodologies which potentially could significantly enhance overall protection of the public health and safety. Various pilot studies considering performance-based approaches and risk-based approaches to inspection / testing look promising for such enhancements. However, necessary resources are currently being diverted to implement Code changes that the Commission has already determined will only provide slight changes to public risk, if any.
F.
BURDEN REDUCTION ASSESSMENT t
Maintaining the ISI and IST programs involve numerous costs. The actual quantitative potential for burden reduction cannot be calculated since it depends greatly on the specific Code changes which might be made in the future. The following discussion provides insights to the areas that would be positively affected by this burden reduction initiative.
1.
The existing requirement in 10CFR50.55a provides for the submittal of relief requests by licensees. It ensures that in those cases where the generic requirements of Section XI are impractical, or are unnecessarily burdensome for a specific facility, that facility may obtain relief from the particular requirement, provided the licensee demonstrates to the Commission that omission of the Section XI requirement believed to be impractical will not have an adverse effect on public health and safety.
Submittal of relief requests imposes resource and financial burden on both the licensee and the Commission staff. Additional review and approval of relief from new requiremena that provide no substantialincrease in safety clearly costs more than performing an evaluation of the potential safety impact of a change. Although this does not represent a substantial cost, Entergy Operations' proposed alternative would incorporate a process that
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i is less burdensome than the relief request process described in 10CFR50.55a.
2.
Small, seemingly inconsequential Code changes can subsequently drive higher costs simply because of the resulting procedure changes. At i
GGNS, tl e IST and Pressure Testing portions of the ASME Code requirements are incorporated into more than 2400 component procedures. For Grand Gulf Nuclear Station, procedure changes typically 7
average $2.7 K per procedure, considering preparation, technical publication and review / approval man-hours. The manpower necessary to revise these procedures could be reduced if safety-neutral Code changes were no longer imposed upon the licensee.
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3.
The proposed alternative would allow Entergy Operations to better manage its resources considering potentials for safety improvements by allowing timely incorporation of beneficial Code changes rather than following a fixed 10-year schedule. This benefit of the proposed alternative does not decrease burden, but does allow more flexibility in choosing when to spend available resources.
4.
Licensee engineering review of Code changes varies depending on the number and type of changes involved. Costs (including licensee and contractor manhours) can vary between $50 K and $200 K. Costs are incurred at the end of each ten year interval in preparation for the next ten years. For GGNS, three updates remain in its current licensed operating life. The proposed alternative may actually slight!; :ncrease the review costs since risk evaluations and some cost / benefit evaluations would be performed for those Code changes which were candidates for non-
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implementation.
l 5.
Most of the ISI/IST costs are associated with implementation; therefore, it i
is reasonably expected that the major potential for burden reduction would i
be associated with the avoidance of implementation of safety-neutral Code changes which are not cost beneficial. The following average costs for GGNS give some insight to the potential areas for savings:
RFOS ultrasonic testing and surface exams
- $400 K RFOS ultrasonic testing and surface exams
~ $320 K RFO5 vessel and automated exams (every other outage)
~ $613 K
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Average cost of interference removal, reinstal-lation, painting, scaffolding for ISI inspections each refueling outage
.5 3 0 0 K Estimate to train eight Entergy Operations persons for initial ASME 1988 Addenda UT examiner i
certification
- $106 K 6.
There are approximately 928 valves and 19 pumps in the GGNS IST (Pump and Valve Program) each requiring a variety of periodic tests and inspections. Some of the test periodicities are quarterly and some are every 18 months.
It is estimated, considering the above base cost information and considering the type of Code changes recently approved by the Commission, that the net 1
result of the proposed change, as discussed above, will be a significant reduction in Entergy Operations' cost (e.g., on the order of $3 M over_ the life of Grand Gulf), more focused attention on safety / risk significant areas of the plant with a corresponding safety benefit, and reduced burden on NRC staff resources allowing them to be redirected to more safety significant areas.
These savings (or future cost increase avoidance) would generally be realized through the non-implementation of future safety neutral Code changes which are not cost justified.
G.
SUMMARY
Compliance with the currently specified requirements for automatic 10-year endorsement of updated editions of the Code can impose licensee burden without a compensating increase in the level of quality and safety.
Entergy Operations proposes to replace the automatic 10-year Code update requirement with a requirement to implement only those updated Code sections that provide a substantialincrease in safety. The proposed alternative would provide an acceptable level of quality and safety.