ML20247P849
| ML20247P849 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 09/19/1989 |
| From: | Michael Ray TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 8909280022 | |
| Download: ML20247P849 (4) | |
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TENNESSEE VALLEY AUTHORITY I
CHATTANOOGA.' TENNESSEE 37401 -
SN 157B Lookout Place S E P 1 9 3 8!!
j U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C.
20555
. Gentlemen:
In the Matter of
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Docket Nos. 50-327 Tennessee Valley. Authority
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50-328 j
SEQUOYAH NUCLEAR PLANT (SQN) - ENGINEERING CHANGE NOTICE (ECN) CLOSURE
Reference:
TVA letter to NRC dated February 3, 1987, "Sequayah Nuclear Plant Units 1 and 2 - Engineering Change Notice (ECN) Closeout and Final Safety Analysis Report (FSAR) Updates" i
TVA has completed an'ECN backlog closure effort equivalent.in scope to that initially envisioned in the referenced letter while. incorporating a " work 1
-smart and safe" methodology to best serve the intent of.the backlog reduction commitment made in that letter.
Therefore, with closure of 749 j
field-completed L-ECNs based on the corrections and substitutions as outlined i
in the following description, TVA considers this commitment complete.
As stated in-the referenced letter, TVA committed to close.approximately 1,150 field-completed ECNs by October 15, 1988. This number was in error in j
that it did not represent the number of field-completed ECNs.
The 1,150 number was generated from a computer count on the outstanding work items list (OWIL). However, the list included items other than field-completed ECNs.
1 These types of items are further described below.
1,150 - TVA's original commitment of field-completed ECNs as generated from the OWIL.
182 - Relicensing ECNs:
Design changes issued prior to the appr.priate
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unit's license. Most were field-completed before licensing. Under l
the design program during this time period, the ECN was closed by design after issuance.
i 170 - Local design change requests (L-DCRs): Design changes that did not have an ECN number assigned. The work is field-complete and needs to I
be reviewed and documented by Nuclear Engineering (NE).
L-DCRs were l
only allowed if the modification was on non-safety-related components and did not affect any other safety-related system or component.
61 - Design change requests (DCRs) (ECN not reautred): Design changes that were done against non-TVA controlled drawings (vendor only) and did not require an ECN or change to the plant.
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749 - L-ECNs: Design changes issued after the plant was licensed.
8909280022 890919 PDR ADOCK 05000327 P
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.,.U.S. Nuclear Regulatory Commission SEP 191989 L:
i In July 1987, TVA reviewed the field-completed ECNs and' developed a list of-749'L-ECNs that are considered to constitute the backlog of field-completed ECNs at the time the original commitment was made. TVA has now closed these 749 L-ECNs subject to corrections and substitutions to be further described.
Backlog items consisting of relicensing ECNs, L-DCRs, and DCRs (ECN not required) are not part of the standard ECN closure process and are not considered part of the original ECN closure commitment.
However, an action plan is being developed to resolve these open items.
These items do not present a potential safety problem, because they were included for evaluation within the scope of the Design Baseline.and. Verification Program as defined in the SQN Nuclear Performance Plan and have been incorporated into the FSAR as applicable. Also, as'part of the corrective actions associated with Notice of
. Violation 88-09-01, SQN reviewed workplans that had been completed for more l
than 90 days and not yet closed-to determine if procedure changes that were outstanding required escalated priority for revision; procedures affecting-operability or restart were revised before restart.
It can be noted that during the closure of the identified ECN backlog, other ECNs have been field-completed. TVA has capital projects to close the remaining field-complete, pre-7,000 series ECNs.
The current program goal for future closure of modifications (i.e., ECNs and design change notices [DCNs])
is 60 days.
Implementation of the new goal tegan in April 1989. The current and future modification backlog should decline accordingly and does not present a potential safety problem because the FSAR update -is now based on field-completion of the modification.
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As previously mentioned, 749 L-ECNs have been closed subject to certain corrections and substitutions considered prudent in achievement of ECN backlog reduction intent. Of the 749 L-ECNs considered as the backlog, 680 were i
closed by the ECN closure process. The remaining 69 ECNs were addressed as l
follows:
i 1.
Three ECNs were volded that were design-complete and issued, but no field work had been started. This required the design change to be removed from design output documents.
i 2.
Nineteen ECNs were determined not to be fully field-complete. Rather than remove these ECNs from the scope of the commitment, these ECNs were 1
substituted in accordance with the substitution criteria described below.
3.
Thirty-three ECNs that were not FSAR-related were substituted with an l
FSAR-related ECN in accordance with the substitution criteria.
4.
Fourteen L-DCRs were assigned an ECN number, but the ECNs were not issued. These ECNs were cancelled, and a DCN was issued under the I
permanent design control process to reflect the L-DCR into design l
documents. The DCNs were subsequently closed.
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l-U.S. Nuclear Regulatory Commission SEP 19 M l
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I The following substitution criteria were used to determine the scope of ECNs within the backlog to be closed. These criteria were primarily developed so that ECNs affecting the FSAR would receive a higher priority than ECNs not-affecting the FSAR.
In this manner, an ECN that was part of the initial list of -749'L-ECNs' but did not Affect the FSAR may have been substituted in the scope of this closure effort by another.L-ECN that did affect the FSAR.
This methodology was previously discussed with NRC. The criteria and methodology were implemented as follows:
1.
Determined which open ECNs from the original listing affected the FSAR, and which ECNs had impact on outstanding secondary drawings / procedures.
2.
Rescheduled those ECNs that were non-FSAR-related and have no procedures / drawings that were outstanding.
3.
Evaluated impact and considered rescheduling ECNs that were non-FSAR-related but had procedures / secondary drawings that were outstanding.
4.
Rescheduled those ECNs that were FSAR-related but not related to critical structures, systems, and components.
5.
Continued the closure effort on any unrestrained (i.e., field-complete)
ECNs that had significant closure effort already expended.
6.
ECNs that had been rescheduled for closure after October 15, 1988, based on these criteria, were to be replaced by pre-7,000 series ECNs that were FSAR-related, had been field-completed since the listing of closure ECNs was first established, and did not have any known restraints.
NE and Modifications Group personnel reviewed the commitment scope of ECNs and deleted those that did not meet the criteria and substituted from the remaining backlog those that did meet the criteria. Quality Assurance reviewed this process to ensure that these criteria were consistently followed.
In summary, TVA has completed an ECN backlog closure effort equivalent in scope to that initially envisioned while incorporating a " work smart and safe" methodology to best serve the intent of the backlog reduction commitment.
TVA has developed processes and programs that should minimize future backlogs and eliminate any safety impact those backlogs could have on operations.
Therefore, with closure of the 749 field-completed L-ECNs based on the above corrections and substitutions, TVA considers this commitment complete.
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. y O.S; Nuclear Regulatory Commission-SEP 191989
.If you have any questions concerning this submittal, please telephone.
M. A.- Cooper.at (615) 843-6651.
Very truly yours, TENNESSEE VALLEY AUTHORITY b
q }p Mana er, Nuclear Licensing'and Regulatory Affairs cc: Ms. S. C. Black, Assistant Director for Projects..
TVA Projects' Division U.S. Nuclear Regulatory Commission-One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 Mr. B. A. Wilson, Assistant Director for Inspection Programs TVA Projects Division U'S. Nuclear Regulatory Commission Region II~
101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 NRC Resident Inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy Daisy, Tennessee 37379
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