IR 05000461/1993010
| ML20058C988 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 11/23/1993 |
| From: | Wright G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Jamila Perry ILLINOIS POWER CO. |
| References | |
| NUDOCS 9312030017 | |
| Download: ML20058C988 (2) | |
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NUCLEAR REGULATORY COMMISSION
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NOV I:21993 Docket No. 50-461 Illinois Power Company ATTN: Mr. J. Senior Vice President Clinton Power Station Mail Code V-275 P. O. Box 678 l
Clinton, IL 61727
Dear Mr. Perry:
This will acknowledge receipt of your letter dated October 18,1993, in response to our letter dated September 17, 1993, transmitting a Notice of Violation associated with Inspection Report No. 50-461/93010. This report
.i summarized the results of the engineering and technical' support inspection
recently conducted at your Clinton Power Station. We have reviewed your i
corrective actions and accept them with the following clarifications:
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Condition report 1-91-01-069 will be provided to the NRC for additional i
review. As your staff stated-in our telephone call, since this t
condition report does not provide complete documentation of adequate
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root cause investigation, other additional information will be provided i
to the NRC, including actions taken since the inspection.
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The first sentence of the last paragraph on page 4 of Attachment 2 -
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states, "No corrective actions beyond those described above are I
warranted." We agree that no_further corrective actions may be necessary for your corrective action program; however, as you clarified, i
additional corrective actions are being taken to include the two
.I additional RHR test return line restraint weld failures.
Finally, we
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understand that you will provide this office with your final analysis
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and corrective action in this matter within 30 days of your January 31, 1994, completion date.
These clarifications were based on a telephone conversation with your staff on
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November 12, 1993. The additional information being provided will be used to
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assist the staff in the final closure of the noted violations. The corrective
actions will be examined during future inspections and we have no further i
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comments on your response to this. inspection.
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Sincerely,
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9312030017 932123 T
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yDR ADOCK 050004618 C-
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N Geoffrey C. Wright, Chief (
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Engineering Branch
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See Attached Distribution l
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't Illinois Power Company
th3V 131993 Distribution
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cc:
J. Cook, Vice President and Manager, Clinton
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Power Station R. F. Phares, Director -
Licensing cc w/ltr dtd 10/18/93:
OC/LFDCB Resident Inspectors - Clinton,
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Dresden, LaSalle & Quad Cities D. Pickett, LPM, NRR
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J. W. McCaffrey, Chief, Public
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Utilities Division
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Ms. K. K. Berry, Licensing Services
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Manager, General Electric Company
Chairman, DeWitt County Board Robert Newmann, Office of Public Counsel, State of Illinois State Liaison Officer Chairman, Illinois Commerce Commission
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imots Paar Company
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Crao, Poaer Station P o Box C75 t
Cv.:on. IL C1727 Te 217 935 0226
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Fan 217 9354632 J. Stephen Perry Senu me Ortodont ILLINOIS POWER U-602197 L42-93(10-18)LP
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JSP'-476-93 l A.120
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October 18,1993 Docket No 50-461 10CFR2.201 Document Control Desk Nuclear Regulatory Commission Washington, DC 20555 Subject:
Illinois Power Response to Notice of Violation 50-461/93010-03 Dear Sir The attachments to this letter provide the lilinois Power (IP) response to the Notice of Violation documented in Nuclear Regulatory Commission (NRC) Inspection Report 50-461/93010 (DRS) The Notice of Violation discusses the safety significance, root cause, and corrective actions for pipe suppen deficiencies found in the Residual Heat Removal (RHR)
systems at Clinton Power Station (CPS)in early 1991. IP's investigation of these deficiencies was also discussed in the NRC Resident inspector's routine repon 50-461/90028 (DRP) dated Febn;ary 15, 1991, and the NRC Systematic Assessment of Licensee Performance (SALP 10)
inspection report 50-461/91001, dated April 11,1991.
The Notice of Violation identified two apparent examples of inadequate root cause analysis and corrective action: 93010-03a and 93010-03b While IP concurs with the second example (93010-3b), IP does not fully agree that the example cited in the first pan of the Notice of Violation (93010-03a) represents an inadequate evaluation of root cause. As a result of this part of the Notice of Violation, IP conducted a detailed review of the documentation associated with the identified RHR pipe suppon deficiencies. IP has concluded that the problems identified in this part of the Notice of Violation,(93010-03a), were the result of poor documentation of the basis for the decisions made during 1991 and not the result of an inadequate root cause evaluation. Therefore, several of the corrective actions taken, in response to this pan of the Notice of Violation, consist of the performance of calculations and analyses which support the conclusions reached in 1991.
IP recognizes that the Clinton Power Station corrective action program of 1990/1991 required enhancements in order to effectively identify and disposition hardware deficiencies. Over the two operating cycles since these events occurred, IP has made many improvements to its corrective action program These improvements include strengthened management oversight; the lowering of the threshold for writing Condition Repons,.mprovements in perfe: ming and documenting root cause determinations, and in thoroughness and documentation of corrective f.
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I actions. The corrective action program improvements made over the last several years were
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l previously reponed to the NRC in separate correspondence.
i Additionally, IP personnel are now more experienced at initiating and documenting
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operability judgments. IP has conducted formal training on Generic Letter 91-018, issued on i
November 11,1991, entitled "Information to Licensees Regarding Two NRC Inspection Manual
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Sections on Resolution of Degraded and Non-Conforming Conditions and on Operability."
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Aside from the Notice of Violation, the inspection report indicated that there was room l
for improvement in the quality of some of our engineering products. IP values those constructive
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comments and will use them to further improve our program.
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Sincerely yours, i
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.S.Pe i
Senior Vice President
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SSG!nis
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Attachments
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NRC Clinton Licensing Project Manager cc.
l NRC Resident Oflice, V-690
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NRC Regional Administrator, Region 111 l
I Illinois Depanment of Nuclear Safety l
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Attachment 1
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to U-602197 Page 1 of 6 -
IP Response to Notice of Violation 50-461/93010-03A (DRS)
The Notice of Violation states:
" Criterion XVI of 10CFR50, Appendix B, requires that measures be established to assure that conditions adverse to quality, such as failures and deficiencies, are promptly_ identified and j
corrected. In the case of significant conditions adverse to quality, the measures shall assure that
the cause of the condition is determined and corrective action taken to preclude repetition.
Contrary to the above:
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The licensee identified and documented more than a dozen pipe support deficiencies in the RHR systems "A" and "B", including damage to four rigid pipe restraints, in condition reports (CRs) dated January 8 and January 17, 1991. The CRs were closed without adequate assessment to determine the root cause(s) and safety significance (461/93010-'
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03A(DRS))."
Backcround and Chronolocv of Events As a result of this violation, Illinois Power performed a detailed review of the documented facts, analyses performed, and corrective actions that were taken to respond to the pipe support deficiencies identified in the CRs dated January 8, and January 17,1991.
The RH09 subsystem (analytical model designation) serves as a suction supply to both the "A" and "B" loops of the Residual Heat Removal (RHR) system for shutdown cooling operation as well as for other modes invoMng suction from the suppression pool.
Just prior to and during the second refueling outage (RF-2), from October 14,1990, to March 9, 1991, visual inspections of component supports were performed in accordance with the requirements of the American Society of Mechanical Engineers (ASME) Code and the CPS In-Service Inspection (ISI) Program. These inspections identified some supports that needed minor rework, including tightening oflock nuts, removal of debris from spring cans, and adjustment of suppon IRH09027S to clear an interference.
On January 8,1991, while performing the maintenance work on these minor issues, personnel identified four suppons in the RH09 subsystem which were not in accordance with design. The
discrepancies on hangers 1RH09028X, IRH09029S,1RH09030X, and 1RH09031S were reponed on Condition Repon 191-01-029 the same day they were found. These discrepancies '
i all dealt with misalignment of the hangers, and in one case an additional problem ofinterference between suppon IRH09031S and an adjacent pipe. The Condition Repon was designated as not significant.
i Attachment I to U-602197 Page 2 of 6 At CPS, conditions adverse to quality that are documented on Condition Repons are designated
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as either significant or not significant. A significant condition is one that afTects or is likely to have an effect on, or influence, the safe operation of the plant, the capability to shut down the
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reactor and maintain it in a safe shutdown condition, or the capability to prevent or mitigate the consequences of accidents which would result in potential offsite exposures. CPS management
may also designate other conditions adverse to quality as significant at their discretion.
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The very next day, January 9,1991, an engineering walkdown of supports, piping flanges, and instmment lines in the area of the RHR *B" pump room suction piping was conducted to look for indications of a significant operational transient (water hammer event). The walkdown revealed j
damage to suppon IRH09035X and misalignment /misadjustment of suppons IRH09002X,
1RH09032S, and IRHOS072X. Discrepancies such as misaligned clamps, loose nuts, and a sway strut with a bent extension were noted. A Maintenance Work Request (MWR D15608) was i
issued to adjust those suppons.
On January 10,1991 Engineering issued an evaluation of Condition Repon 1-91-01-029 which l
stated, "Although the cause of these discrepancies is still under investigation, there was no evidence of damage to instrumentation, flange leakage, snubber or variable suppon significantly out of adjustment, or insulation damage which would be indicative of a significant operational
transient." The evaluation indicated that the system had sufficient structural integrity to withstand
a seismic event and to support Mode 4 operation. However, the evaluation prohibited operating the system above 200 degrees Fahrenheit while the investigation continued to determine the cause of the condition.
l The suppons in the RHR "B" pump room were reworked and adjusted on January 11,1991.
Other actions taken to investigate Condition Report 1-91-01-029 were (1) a review of visual inspection reports documented during RF-1 and up to this point in RF-2, including those done in October,1990, which did not indicate any other significant suppon conditions such as those noted in the Condition Repon; (2) a review of operator logs and operating pump cycles of the system;
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(3) a discussion with the RHR pump vendor which indicated that the number of pump cycles was not excessive; and (4) confirmation that there was some cavitation evident for the first few minutes during pump startup. From this investigation, the root cause was determined to be vibration, likely resulting from cavitation during pump startup conditions. Because vibration was j
determined to be the cause, it was imponant that extended structures be reviewed to ensure they were not highly stressed. The yokes on valves IE12-F004A/B and IE12-F006A/B were later inspected and no damage was found.
On January 14,1991, the accessible ponions of the RHR "A" pump room suction piping and the common header of the shutdown cooling suction piping were also walked down. Some RHR "B" loop piping in the "B" RHR lleat Exchanger room, which was inaccessible on January 9th, was also walked down. During this walkdown, suppon IRH09066X was found to be damaged, and supports 1RH09049X, IRH09058X, 1I0109065S, and IRH09080X required minor adjustment / alignment.
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Attachment 1 i
to U-602197
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Page 3 of 6 It is important to note that hanger 1RH09066X, found damaged during this January 14th
walkdown, had been inspected previously on October 13, 1990, and January 8,1991. Neither
inspection found a bowed strut assembly. Equally important to note is that the walkdown on
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January 14th did not identify any damage to suppon 1RH09015R, which was in the area. As will l
be seen, these facts became critical during the subsequent investigation, and will help to explain l
why Illinois Power took the actions it did.
Following the January 14th walkdown, adjustments were made to supports found to be incorrectly positioned.
On January 17, 1991, only three days after the last walkdown, while making adjustments to
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adjacent hangers, suppon IRH09015R embed plate was now found to be damaged. This damage j
was promptly reported on Condition Report 1-91-01-069. The Condition Repon was designated
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as significant. By this time, suspicions started to form that damage was occurring sometime during the ongoing refueling outage.
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On January 19,1991, based on visual inspections made by Engineering personnel the day before, Engineering issued an evaluation which concluded that the IRH09015R " support was not performing its design function." Engineering recommended that the associated RHR "A" loop not be placed into senice for any reason until the condition was corrected. Based on the results of the walkdown of the corresponding supports on the RHR "B" loop, which did not identify any
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discrepant conditions, and the reduced loading conditions now imposed during plant shutdown,
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Engineering indicated that operation of RHR "B" was still permissible, although the 200 degrees
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Fahrenheit restraint was still imposed. Later, a design change was issued to repair suppon
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1RH09015R.
I On January 21. 1991, a concern was identified with the embed plate for suppon IRH09002X,
which was later found to be acceptable. Nonetheless, funher field work on the suppons was l
suspended due to the possibility that suppon manipulations were actually causing the newly
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reported discrepancies. IP broadened its investigation into a complete analysis of the RHR suction piping. A plan was developed by Engineering to systematically and methodically evaluate -
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the condition of the piping / supports and to sequence the rework activities to ensure no additional damage to the RHR system occurred.
On January 24, 1991, the operating temperatures in the piping system had stabilized at approximately 100 degrees Fahrenheit and, with system manipulations halted, detailed engineering walkdowns of the entire subsystem were performed. Photographs and critical characteristics obsened were taken for each suppon for later review. These walkdowns were divided into four areas based on accessibility including the RHR pump room "A", RHR pump room "B", common shutdown cooling suction header, and the steam tunnel.
After review and evaluation by Sargent & Lundy (S&L), selected snubbers were stroked with '
acceptable results. Then hangers in these portions of the piping system were adjusted to correctly rebalance the system. This included the adjustment of stmts and variable supports, with some temporary suppons installed as required to assure that the pipe did not move in a manner which would result in overstressing.
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Supports IRH09066X and IR1109015R were also reworked / repaired at this time under MWRs D15700 and D15706. These actions returned the supports for the RHR "A" suction piping and the common header of the shutdown cooling suction line to their design configuration. The RHR
"A" loop was then placed into shutdown cooling mode of operation and the RHR "B" loop was i
shut down. After being shut down, the temperature of the RHR "B" loop was stabilized.
The RHR "B" loop pump suction piping suppons were then adjusted to bring them back to design configuration using an approach similar to that used for the RHR "A" loop. Hanger 1RH09002X embed in the "B" RHR loop was evaluated and found to be acceptable.
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Data and analyses of credible root causes were collected in order to determine the root cause. A matrix providing an assessment of each of eleven possible causes was prepared.
On Febmary 8,1991, Engineering issued its final evaluation of Condition Repon 1-91-01-069 which indicated that no one single event was the cause of all the problems, rather each was the result of various combinations of causes discussed above (i.e., cavitation-induced vibration, rework activities, etc.).
All of the above rework received visual (VT-3) inspections. Further corrective actions included three obsenations of the start of both "A" and "B" RHR loops to ensure no excessive or unexpected movement of the suction piping could be obsened. No transients which could cause funher degradations of the pipe support system were seen. A review was conducted to determine if any changes were needed to operating procedures to ensure that operating sequences would not cause water hammer or pipe transients. The existing operating procedure steps were found to be appropriate. To provide funher assurance, during a forced plant shutdown, on January 10,1992 a walkdown of the RHR shutdown cooling piping hangers was again performed during hot conditions to confirm that suppons were still functioning properly. All conditions observed during the walkdown werejudged as acceptable.
In summary, the investigation and analysis described above included (1) a full engineering walkdown of all the suction piping; (2) reworking of all identified discrepancies; (3) installation of temporary suppons to allow manual stroking of selected snubbers; (4) adjustment of struts and spring cans to balance the support loads per design documents; (5) redesign of the IRH09015R suppon and repair of the embed plate and concrete; (6) a review of the operating history and vibration analysis to identify possible transients that could have caused the problem; (7) a review of maintenance activities such as system draining and installation of temporary shielding for possible effects; and (8) a review of piping layout and valve sequencing and stroke times to determine if any hydraulic transients were possible. Through this original investigation, IP was able to eliminate the possibility that a water hammer event caused the pipe support deficiencies.
This indicates that, contrary to portions of the stated violation, an adequate root cause investigation was performed and appropriate corrective actions were taken.
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Attachment I to U-602197 Page 5 of 6
Reason for the Violation
i The above background discussion reflects what was documented in the various Condition
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Reports, engineering evaluations, memoranda, and reports of the period. As noted from this
discussion, IP concluded that minor discrepancies occurred due to vibration, and funher j
discrepancies were created while rectifying the minor problems during the outage. On this br. sis, IP did not consider pre-outage operability any funher.
The violation was cited because IP was unable to provide suflicient evidence to the inspector during the recent Engineering and Technical Support (E&TS) inspection that the root cause(s)
was adequately identified. Without adequately identifying the root cause(s), IP could not assume i
the position that operability need not be considered, and IP could not be assured that the corrective actions would prevent recurrence.
Although there were suflicient evaluations to conclude that the root causes had been identified, the violation is correct in that IP, based on its root cause determination, did not clearly document
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its rationale for concluding that the RHR system was operable during the previous operating cycle and that a water hammer event did not cause the pipe support discrepancies.
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Corrective Action Taken and Results Achieved i
In response to this violation, IP has performed a preliminary analysis to show that the RHR system would have remained operable even if the two snubbers first observed as damaged were removed from the system. This analysis indicates that the system would have remained capable of performing its design basis function in this hypothetical situation. This analysis is undergoing formal review and will be final by December 31,1993.
Also, in response to this violation, a set of preliminary calculations have been performed to show that it was indeed possible to damage support components by performing support manipulations during the outage. The calculations will be formally reviewed and approved by December 31, 1993.
a IP believes the results of these additional calculations will funher support the original root cause determinations. Since the discrepancies have been reworked and system observations have indicated no unusual operating conditions, IP contends that appropriate corrective actions were taken to prevent recurrence.
Corrective Actions to be Taken to Avoid Further Violations Over the two operating cycles since these events occurred, JP has made many improvements to its corrective action program. These improvements include strengthened management oversight; the lowering of the threshold for writing Condition Reports; improvements in performing and documenting root cause determinations, and in thoroughness and documentation of corrective
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Page 6 of 6
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actions. The corrective action program improvements made over the last several years were
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previously reported to the NRC in separate correspondence.
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Additionally, IP personnel are now more experienced at initiating and documenting operability
judgments. IP has conducted formal training on Generic Letter 91-018, issued on November 11,
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1991, entitled "Information to Licensees Regarding Two NRC Inspection Manual Sections on
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Resolution of Degraded and Non-Conforming Conditions and on Operability."
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Engineering personnel have been made aware of the events surrounding this violation and the
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lessons learned from it.
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No further corrective actions are warranted. IP remains in comphance.
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Attachment 2 to U-602197 Page 1 of 4
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IP Response to Notice of Violation 50-461/93010-03B (DRS)
The Notice of Violation states:
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" Criterion XVI of 10CFR50, Appendix B, requires that measures be established to assure that conditions adverse to quality, such as failures and de6ciencies, are promptly identified and corrected. In the case of significant conditions adverse to quality, the measures shall assure that I
the cause of the condition is determined and corrective action taken to preclude repetition.
Contrary to the above:
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Cracked welds were identified and documented on the RHR pump "B" discharge pipe l
guide in a CR dated Febmary 5,1991.
The condition report was closed without l
inspection of similar pipe guides and assessment of the safety significance (461/93010-
03B(DRS))."
l Background 4nti Chronolocy of Events
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The "A" loop Residual Heat Removal (RHR) system full flow test return line enters containment through penetration MC-18 approximately nine feet above the normal level of the suppression l
pool. The "B" loop RHR test return line enters the containment through penetration MC-20 approximately 21 feet above the normal suppression pool level (this line enters the containment about 12 feet higher than the corresponding "A" line).
Modification RHF015 added additional lengths of pipe to extend the discharge point of the test return lines deeper into the suppression pool. On Febmary 5,1991, while installing modification RHF015 on the "B" loop RHR system full flow test return line, workers noticed four cracked welds on box guide IRH30003G. Approximately two dozen other box guide welds had no apparent cracks. The box guide is a type of support which attaches the test return line to the suppression pool stainless steel liner. A Condition Report was immediately written to identify the condition. The Condition Report was designated as significant.
The box guide v.as repaired by reworking the cracked welds in accordance with Field Engineering Change litic:: (FECN) 27047. This change added two additional fillet welds on the side of the plate opposite of two of the cracked welds, and increased the weld size for the other two cracked welds.
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Attachment 2
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to U-602197 Page 2 of 4 An engineering evaluation was prepared which indicated that, through a review of related Maintenance Work Requests (MWRs), interviews of persons working around the box guide (IRH27003G) for the "A" loop of RHR, and field inspection of the box guide (IRH30003G) with the failed welds on the "B" loop of RHR, all other welds were determined to be acceptable. The original construction plant traveler package H-RH-26-D was reviewed to determine if any original'
construction activities could have contributed to the weld failures. The review did not reveal any abnormal material or work sequencing.
Funher, a review of the differences between MC-18 and MC-20 piping configurations was
performed to determine if there were any attributable parameters which could have caused the j
weld failures. The review indicated that MC-20 entered the area above the suppression pool approximately 12 feet higher than MC-18. This results in some cavitation in the pipe at the higher elevation, resulting in pipe vibration and resultant cyclic loading on the guide.
On Febmary 9,1991, the RHR "B" loop was operated. During the first pump run, hich noise
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level was reported and pipe movement was observed. During a second run two hours later, the noise level was lower and pipe motion was less. The only difference between these two runs was that the suppression pool level had increased approximately one foot. This increase in level would i
have created more back pressure on the flow and reduced the cavitation. The amount of observed pipe vibration was viewed as acceptable.
Based on the investigation discussed above, IP was unable to identify conclusively the root cause of:he weld failures. However, the engineering evaluation postulated that the original weld may have had minor undetectable defects. The defects may have developed into weld cracks due to cyclic loading from process pipe movement when the system was in sersice. The strengthening and addition of welds in accordance with FECN 27047 added additional margin to the guide design to improve its structural strength.
Reason for the Violation
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IP failed to (1) document the safety significance of the failed welds; (2) evaluate other potential failure mechanisms; (3) document in its engineering evaluation the basis for choosing only one
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other similar box guide for consideration; and (4) perform a viwal inspection of the other similar guide in 1991.
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I Upon reevaluation, IP has verified that, in light of the postulated failure mechanism, box guide IRH27003G is the only support similar to box guide IRH30003G that had failed welds. This,
similarity is principally due to 90-degree elbows that are attached to the~ discharge ends of both lines considered (this fact was not documented in the earlier assessments). The elbows are there to provide more circulation and promote uniform temperature throughout the suppression pool.
Discharges through these elbows during system operation create forces in the opposite direction, i
causing additional pipe vibration and cyclic loading on the box guides. These are the only two pipe lines discharging into the suppression pool with such elbows. Our investigation revealed that all other pipe discharges are either balanced such that no reactive forces are created, or any forces
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Attachment 2 to U-602197 Page 3 of 4 created as a result of discharge are in a direction such that no additional loadings are experienced l
by their associated box guides. Funhermore, upon review of the water quality of the suppression pool, corrosion-induced cracking (a failure mechanism mentioned by the inspector)is not credible.
The inspection repon indicates that there are seventeen other similar pipe guides in the RHR system, however, there is actually a total of twenty pipe guides in the RHR system. Of these
twenty, only two are similar in that they are subject to the vibration-induced cyclic loading (described previously) that caused the noted failures. These two supports were considered in the original Condition Repon evaluation and were subsequently scheduled for reinspection.
However, a safety significance and operability evaluation should have been performed at the time,
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since it is likely that the cracks existed during plant operation.
f In summary, the basis of the decisions made should have been documented, and a safety signif.cance evaluation should have been performed.
i Corrective Action Taken and Results Achieved
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As a result of this concern, IP has performed a preliminary analysis of the as-found condition which concluded that, even if the crack.ed welds were completely absent, the box guide was j
capable of performing its design function, including tolerating loading from suppression pool swell
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during a design basis loss-of-coolant accident. This analysis will be formalized and completed by i
December 31,1993.
IP has also reopened the original Condition Report to (1) incorporate the results of the recent f
operability analysis of the as-found condition; (2) more thoroughly document the root cause j
determination; (3) document the rationale why only one other box guide is regarded as similar to
the failed box guide; and (4) document the results of the inspections performed during the current
refueling outage.
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On October 15, 1993, during the current refueling outage (RF-4), IP performed the previously l
scheduled visual inspections of the two box guides. No discrepancies were found during the
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visual inspection of the RHR "A" loop box guide (IRH27003G). The visual inspection of the l
RHR "B" box guide (1RH30003G) revealed two weld cracks. These new cracks were identified
in welds different than those found in 1991. A Condition Report has been written. Engineering
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has performed a preliminary analysis of the as-found condition and has conclud:d that the box guide will perform its design function during design basis events in all modes of operation. IP is
continuing its investigation and will take funher conective actions.
j Corrective Actionsio be Taken to Avoid Funber Violations Over the two operating cycles since these events occurred, IP has made many improvements to its corrective action program. These improvements include strengthened management oversight; the lowering of the threshold for writing Condition Reports; improvements in performing and documenting root cause determinations, and in thoroughness and documentation of corrective l
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l Attachment 2
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to U-602197
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Psge 4 of 4 actions. The corrective action program improvements made over the last several years were i
previously reported to the NRC in separate correspondence.
i Additionally, IP personnel are now more experienced at initiating and documenting operability
judgments. IP has conducted formal training on Generic Letter 91-018, issued on November 11, i
1991, entitled "Information to Licensees Regarding Two NRC Inspection Manual Sections on Resolution of Degraded and Non-Conforming Conditions and on Operability "
Engineering personnel have been made aware of the events surrounding this violation and the
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lessons learned from it.
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No corrective actions beyond those described above are warranted. IP will be in compliance by January 31,1994.
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