IR 05000263/1997007
| ML20216B237 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 09/02/1997 |
| From: | Grobe J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Wadley M NORTHERN STATES POWER CO. |
| References | |
| 50-263-97-07, 50-263-97-7, NUDOCS 9709050260 | |
| Download: ML20216B237 (2) | |
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September 2 1997 Mr. M. Vice President, Nuclear Generation Northern States Power Company 414 Nicollet Mall Minneapolis, MN 55401 SUBJECT: NOTICE OF VIOLATION (NRC INSPECTION REPORT 50 263/97007(DRS))
Dear Mr. Wadley:
This will acknowledge receipt of your August 15,1997 letter in response to our July 10,1997 letter transmitting a Notice of Violation associated with the above mentioned inspection report. This report summarized the results of the maintenance rule inspection at your Monticello Plant. We have reviewed your corrective actions and h;ve no further questions at this time. These corrective actions may be examined during future inspections.
Sincerely, original signed by J. A. Grobe John A. Grobe, Acting Director l 4 Division of Reactor Safety $
i Docket No.10 263 i \
- Enclosure: Ltr 08/15/97, W. J. Hill, NSP, to US NRC w/enci See Attached Distribution l 050032 //a /
DOCUMENT NAME: G:\DRS\ MON 082_7.DRS To receive e copy of this document. Indicete in the box 'C" = Copy w/o attach /enci T = Copy w/ attach /enct *Y = No copy 0FFICE Rlli:DRS 6 Rlli:DRS;; // Rill:DRP l // Rill:DRS m a NAME Dunlop/kjc 6 r- GavulaWhy McCormick Bargen pacobson @ y DATE 08/2r/97 08'tr /97 v 08/ 2 /97 V 'Og// /97/
9709050260 970902 TICIAL RECORD COPY-
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PDR ADOCK 05000263- _
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M. September 2 1997 cc w/o encl: Plant Manager, Monticello cc w/ encl: John W. Ferman, Ph.D.
Nuclear Engineer, MPCA State Liaison Officer, State of Minnesota Q]stribution:
Docket file w/enct Rill PRR w/enci J. L. Caldwell, Rlll w/enct PUBLIC IE-01 w/ encl SRis, Monticello, Rlli Enf, Coordinator w/enci OC/LFDCB w/ encl Prairie Island w/enct TSS w/enci DRP w/ encl LPM, NRR w/enci DRS w/enci A. B. Beach, Ritt w/enci
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Northern States Power Company Monticello Nuclear oenerating Plant 2807 West Hwy 75 Monticello. Minnesota $$362-9637 August 15,1997 10 CFR Part 2 Section 2.201 US Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 MONTICELLO NUCLEAR GENERATING PLANT Docket No. 50 263 Licenso No. DPR 22 Reply to Notico of Violation Contained in NRC Insocction Rooort No. 50-263/97007 Pursuant to the provisions of 10 CFR Part 2, Section 2.201, our replies to the notico of violation and untosolved item contained in your letter of July 16,1997, are provided in Attachments A and B, respectively.
Attachmont A, Reply to Notice of Violation, contains the following now NRC commitment:
The Monticello Maintenanco Rufo Program Docurnent EWI 05.02.01 shall be revised to describe the now methodology used to develop the reliability critoria by October 15,1997.
Attachment B, Reply to Unresolved itom, contains the following two now NRC commitments that will bo incorporated into our ongoing Maintenanco Rulo Program:
The Structures System Basis Document will be revised to clarify what constitutes the initial baseline inspection and what deficiencios should bo logged in the civil engincor's notobook.
Survoillanco 1385, Periodic StructuralInspection, will be revised to provido additional guidance for the civil angincor as to when a deficiency is acceptable, referenco existing structural monitoring programs, clarify what comprised the initialbaselino inspection, revise Table 1 to divido largo structures into smaller sections, and to develop forms and guidance to improve the plant's permanont record by providing a separato inspection review shoot for each structuro, a separato structural deficiency form, and a deficiency documentation process.
Pleaso contact Marcus Voth, Program Manager Lconsing (612 2715116), if you require further information.
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William [H '
Plant Manager Monticello Nuclear Generating Plant Cf] d W b Y -??
MMl7 WN J UCENSENIOLVR977Nov COC
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. REPLY TO NOTICE OF VIOLATION Attochmont A Page2 August 15,1997 c: Regional Administrator lil, NRC NRR Project Manager, NRC St Resident inspector, NRC State of Minnesota Attn: Kris Sanda J Silberg Attachments A . Reply to Notico of Violation D Reply to Unresolved item
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REPLY TO NOTICE OF VIOLATION Attachment A Page 3 August 15,1997 Violation:
10 CFR 50.65(a)(1) toquires, in part, the holders of an operating license shall monitor the performance or condition of structures, systems or components (SSCs), against licensee-ostablished goals, in a manner sulficient to provide reasonable assuranco that such SSCs as defined in 10 CFR 50.65(b), are capablo of fulfilling their intended functions. Such goals shall be established commonsurate with safety. When the performance or condition of a SSC does not moot established goals, appropriato corrective action shall be taken.
10 CFR 50.65(a)(2) requiros, in part, that monitoring as specified in 10 CFR 50.65 paragraph (a)(1) is not required where it has boon demonstrated that the performance or condition of a SSC is being oflectively controlled through the pedormance of appropdate preventivo maintenanco, such that the SSC romains capable of podorming its intended function.
Contrary to 10 CFR 50.65(a)(2), as of July 10,1996, the time that the licensoo elected to not monitor the podormance or condition of certain SSCs against licensoe established goals pursuant to the requiroments of Section (a)(1), the licensee had not demonstrated that the performance or condition of corfain SSCs within the scope of 10 CFR 50.65 were being etfactively controllod through the performance of appropriate proventive maintenance, as evidenced by the following examples, each of which constitute a separate violation:
flointion Examole A A. The licensee had not demonstrated that the performance of the primary containment isolation system, the diesel fuel oil standby pump, the reactor building component cooling water standby pump, andprimary radiation monitors were being offectively controlled through the podormance of appropriate proventivo maintenance in accordance with the requirements of 10 CFR 50.65(a)(2). Specifically, the licensee had failed to establish adoquate measures to ovaluate the effectiveness of the performance of appropriate preventivo maintenance on those SSCs prior to placing those SSCs under Scction (a)(2). The licensee hadpodormed preventivo maintenance on the SSCs; however, the appropriatonoss had not been adequately evaluated for SSC reliability or unavailability, which was necessary to demonstrate the offactiveness of proventive maintenanco. As a result, it was not demonstrated that the systems were controlled such that they remained capable of performing their intended function. Therefore, the licensee's technical basis for placing those SSCs under the requiromonts of 10 CFR 50.65(a)(2) was inadoquate and those standby SSCs should have been monitored in accordance with to CFR 50.65(a)(1)(263/97007-01(DRS)).
This is a Severity LovelIV violation (Supplement I).
N_SP_R, esponse to Violation NSP acknowledges the above Notice of Violation.
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REPLY TO NOTICE OF VIOLATION Attachment A Pago4 August 15,1997 Although these systems woro not being monitored at the appropriato level in accordance with the Maintenance Rule, they were being monitored by other plant programs and processes (such as the Work Order Process, the Recurring Problems Program, the Repeat Work /Rowork Investigation Process, and the Condition Report Process) outsido of tho Maintenanco Rulo that would have identified ineffective maintenanco.
Reason For Violation The systems identified in this violation were being monitored with plant level performanco critoria instead of specific system or train level critoria such as unavailability or reliability because they had boon classified as "normally operating." Tho standby functions of components in these systems that are not in continuous operation woro not addrossod. Since the performanco monitoring for these systems was not at the appropriate level, NSP did not have a technical basis for classifying these systems as 10 CFR 50.65(a)(2) and, by default, should have classiflod thom as 10 CFR 50.65(a)(1).
For systems such as Diosol Oil Storage (DOL) and Reactor Building Closed Cooling Water (RBC) that are normally operating and have a redundant pump in standby, the Export Panol did not require the development of specific performanco critoria for the standby pump in accordance with the guidance of NUMARC 93 01. The Panel focused on the fact that the function was normally oporating and that a loss of function would be dotected by plant level performanco critoria. The standby pump was inadvortently overlooked. Thorofore, the Panel wrongly concluded that monitoring at the plant level was sufficient.
The Export Panel initially considorod the Primary Containment Isolation System (PCIS)
and the Process Radiation Monitoring System (PRM) to be normally operating systems since those systemu are normally energized and could be considorod to be " monitoring" their input signals. Therefore, these systems were being monitored with plant lovel performance critoria in accordanco with the guidance of NUMARC 93 01 for normally
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operating, non risk significant systems. However, Revision 2 of Regulatory Guido 1.160, " Monitoring the Effectiveness at Nuclear Power Plants,' issued in March of 1997, provides more specific information on the definition of ' standby " This expanded definition requires the PCIS and PRM systems to be considered " standby" systems and not normally operating systems.
Corrective Action Taken and Results Achieved Specific performanco critoria were developed for the standby structures, systems, or components (SSCs) identified above. The Expert Panot reviewed and approved those criteria on August 12,1997.
All other normally operating systems in the Maintenance Rule were reviewed to ensure that they are truly normally operating considering the guidance in Reg Guide 1.160, Revision 2, concerning the definition of " standby " The standby pump for the Stator Cooling System and the standby Emergency Seal Oil Pump (ESOP) for the Hydrogen Seal Oil System were identified as additional standby SSCs requiring specific
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REPLY TO NOTICE OF VIOLATION Attachment A Page 5 August 15,1997 performance criteria. Specific criteria were developed for these components. The Expert Panel reviewed and approved these critoria on August 12,1997. No additional SSCs were identified during this review. '
Historical performance data from July 10,1993 to the present was reviewed and compared to the performance criteria for preliminary (a)(1)/(a)(2) determinations. The preliminary de'ermination shows that the (a)(1)/(a)(2) status of the affected systems remains unchanged. This means that none of the affected systems are exceeding their performance criteria.- The Expert Panel will finalize these determinations at the meeting i to review the 3rd Quarter Maintenance Rule Periodic Assessment Report.
All of the above activities will be documented in the 3rd Quarter Maintenance Rule Periodic Assessment Report.
The Maintenance Rule Expert Panel reviewed the causes of this violation on June 26, 1997 as training to prevent recurrence.
Corrective Action to be Taken to Avoid Further Violations No further actions are required.
Date When Full Comollance Will Be Achieved Full compliance has been achieved.
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REPLY TO NOTICE OF VIOLATION Attachment A Page 6 August 15,1997 Violationhamole B B. ' The licensee had not demonstrated that the performance of the residual heat removal
' pumps, the residual heat removal service water pumps, the standby service water .
pumps, the safety relief valves, and the reactor core isolation cooling system were being
. effectively controlled through the performance of appropriate preventive maintenance in accordance with the requirements of 10 CFR 50.65(a)(2). Specifically, the licensee had failed to esteNish adequate measures to evaluate the effectiveness of the performance of appropriate preventive maintenance on these high safety (risk) significant SSCs prior to placing these SSCs under Section (a)(2). The measures were inadequate because -
there was not a technicalJustification to allow these SSCs to have reliability and availability measures that were inconsistent with the assumptions in the licensee's probabilistic risk assessment (PRA).- The measures established for these SSCs would allow failure rates that were between one and two orders of magnitude greater than the reliability and availability assumptions in the licensee's PRA. Thus, multiple failures or high unavailability would need to occur before the licensee considers moving these SSCs to the (a)(1) category. As a result, it was not demonstrated that the systems were controlled such that they remained capable of performing their intended function, Therefore, the licensee's technical basis forplacing these SSCs under the requirements of 10 CFR 50.65(a)(2) was inadequate and these high safety (risk) SSCs should have been monitored in accordance with 10 CFR 50.65(a)(1) (263/97007 02(DRS)).
- This is a Severity LevelIV violation (L pplement I).
NSP Response to Violation NSP acknowledges the above Notice of Violation.
Beason For Violation
~The PRA sensitivity study which combined the effects of both the availability and reliability criteria did not adequately show that performance criteria were consistent with PRA assumptions.
Initial unavailability criteria were developed by calculating the delta probability change when a set change in baseline Core Damage Frequency (CDF) is divided by tne Birnbaum value. The NEl/EPRI PSA Application Guide was used to select this set change in baseline CDF of approximately 27% These initial values were then compared against similar BWR 3/4 Individual performance criteria to establish a draft set of performance criteria. . A PRA sensitivity study was then performed on the draft performance criteria by requantifying the PRA with all SSC unavailabilities set at the performance criteria value to determine the overall effect aad also the major core
._ damage contributors. After several minor cdjustments in the draft performance criteria,
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'as a result of the sensitivity study, the criteria were reviewed by the Expert Panel for consistency between systems and appropriateness of the absolute vaiaes. The
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performance criteria were finally reviewed by the associated System Eagineer and compared against Monticello historical data from January 1992 through June 1996. A
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REPLY TO NOTICE OF VIOLATION Attachment A Page 7 August 15,1997 final PRA sensitivity study was then completed with the finalized unavailability performance enteria.
For the setting of the initial reliability performance criteria for Maintenance Rulo systems requiring this measure, the Expert Panel used the Emergency Diesel Generator (EDG)
System as a benchmark. This system already had a reliability program in place due to the requirements of Reg Guide 1.155, Reg Guide 1.9 and NUMARC 87-00 " Station Blackout". The Monticello EDGs have a targeted reliability of 95% NUMARC 87-00 specifies acceptable reliability values for a 95% reliable Diesel Generator System as follows:
3 failures out of last 20 tries, 5 failures out of last 50 tries, and 8 failures out of last 100 tries.
These values and the relative imr < 1ance of the Diesel Generator were compared to
, other Monticello sy',tems to estabush an initial reliability maintenance preventable functioeal failmc (rAPFF) value, initial values were then reviewed by the Expert Panel for l consistency between systems and appropriateness of absolute values. The performance crlieria were reviewed by the associated System Engineer and compared against Monticello historical data from January 1992 through June 1996. Finally, MPFF values were compared against system unavailability values for overall consistency.
Finally, a sensitivity study was performed using both the availability and reliability criteria to evaluate the combined effect on CDF. NSP believed that this study provided the
" link" needed to show that the performance criteria were consistent with the assumptions used in the PRA. However, because the methodology used in the study did not use the reliability performance criteria values in all cases, NSP was not able to adequately show that the performance criteria were consistent with the PRA assumptions.
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Corrective Action Taken and Results Achieved
New reliability criteria for the risk-significant systems modeled in the PRA were derived based on a methodology discussed with the NRC PRA inspectors during the course of their Maintenance Rule inspection. This methodology used the Poisson Distribution for normally operating systems and the Binomial Distribution for standby systems to calculate the probability of incurring 0,1,2,3 or more failures over a two-year period.
This method uses the actual PRA assumptions to calculate the reliability criteria if the probability of a given number of failures over the two-year time period was greater than or equal to five percent, this number of failures was the maximum acceptable number of failures over the two-year time period. Reliability criteria for most systems were able to be developed using only this methodology. However, for systems where the results of these calculations did not provide predictive criteria (such as zero allowed failures) or were not realistic, a sensitivity study was performed with these systems using more appropriate reliability criteria. This sensitivity study also included the effects of all the
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l REPLY TO NOTICE OF VIOLATION- Attachment A Page 8 August 15,1997 availability criteria set to their maximum values for risk-significant systems modeled in the PRA. The result was a CDF of less that 1E-4 which is generally recognized as the -
a;ceptance limit. The Expert Panel reviewed and approved the new performance criteria on August 12,1997. -
Historical performance data from July 10,1993 to the present was reviewed and
- compared to the performance criteria for preliminary (a)(1)/(a)(2) determinations. The preliminary determination shows that the (a)(1)/(a)(2) status of the affected systems remains unchanged. This means that none of the affected systems are exceeding their performance criteria. The Expert Panel will finalize these determinations at the meeting
- to review the 3rd Quarter Maintenance Rule Periodic Assessment Report.
All of the above activities will be documented in the 3rd Quarter Maintenance Rule Periodic Assessment Report.
The Maintenance Rule Expert Panel reviewed the causes of this violation on June 26, 1997 as training to prevent recurrence. .i-Corrective Action to be Taken to Avoid Further Violations The Monticello Maintenance Rule Program Document EWI 05.02.01, Sections 6.3.2 and
- 6.3.3 shall be revised to describe the new methodology used to develop the reliability criteria by October 15,1997, Date'When Full Comollance Will Be Achieved Full compliance has been achieved.-
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s REPLY TO UNRESOLVED ITEM- Attachm:nt B Page 1
,. August 15,1997 Unresolveditem Tanks, supports, buildings, and enclosures were adequately scoped as structures under the MR; The guidance and documentation of the structure monitoring program
- were weak andit was unclearif the intent of the MR and the NUMARC guidance was being met with the program currently in place.
Monticello Response
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NSP believes that the existing program meets the_ intent of the Maintenance Rule and the NUMARC/NEl guidance since the inspection procedure and system basis document were developed directly from the Rule and the NUMARC/NEl guidance
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June of 1996 for the in-scope structures. NSP agrees that the guidance and ___
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documentation for the Maintenance Rule Structural Monitoring Program should be enhanced.
Maintenance Rule Structural Monitorina Proaram Enhancements NSP believes that we were in full compliance at the time of the NRC's inspection. _
However, further actions have and will be taken to enhance the program and address the_ Inspectors' concems. These actions are outlined below.
Monticello Surveillance Procedure 1385 was revised from revision 0 to revision 1 to include more specific items to be inspected, more specific guidance as to what to inspect for, and the NRC comments on NEl 96-03, Revision D, as documented in the letter dated October 1,'1996 from Thomas T. Martin (NRC) to Thomas E. Tipton (NEI).
-This surveillance was approved on August 12,1997.
The Structures System Basis Document will be revised to eliminate the discrepancy over what comprised the initial baseline inspection. Specific guidance will also be added to address what tyoe of deficiencies should be kept in the civil engineer's -
deficiency . notebook.- ~ '
Surveillance 1385, Periodic Structural Inspection, will be revised to include criteria,
_where possible, to assist the civil engineer in determining if a deficiency is acceptable.
References to existing structural monitoring programs will be incorporated. The definition of what comprised the initial baseline inspection will be clarified. Table 1 of 1 this surveillance will be revised to divide large structures, such as the Reactor and
' Turbine Buildings, into sections or zones to aid in the performance and review of the inspection. Each structure will also have its own inspection review sheet instead of all _
being located on the same sheet. Also, a separate structural deficiency form shall be added with guidance as to when it should be used. This will provide a specific process for documenting deficiencies and ensure that they become part of the plant's permanent records.
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REPLY TO UNRESOLVED ITEM Attachm:nt B Page 2 ( August 15,1997 Response to inspection Report items Section M1.6.b.4 of NRC Inspection Report 50-263/97007 provided comments concerning the Monticello Maintenance Rule Structural Monitoring Program, in response, NSP provides the following additional information concerning these inspection comments. NSP feels that this additionalinformation further supports our position that the program meets the intent of the Rule and the NUMARC/NEl guidance.
The inspection report states, The completed baseline inspections consisted of a list of ten structures that were considered as either acceptable, acceptable with deficiencies, or unacceptable. The licensee identified the condition of allstructures within scope of the MR as acceptable; no deficiencies with structures w e documentedin the MR program. Discussions with the resident inspector staff revealed several deficiencies where operability evaluations were in place or structural repairs had been completed subsequent to the baseline inspection.
A review of all work orders and condition reports for the Structures System was conducted for the time period between the completion of the structural baseline inspection (June 1996) and the NRC Maintenance inspection (June 1997). No structural deficiencies were identified that should have been documented in the Maintenance Rule Structural Monitoring Program. Upon further discussion with the NRC Senio: Resident inspector on this issue, it was determined that two deficiencies were identified to the NRC Maintenance Rule inspectors. The first was the possible inability of the Reactor Building steel superstructure above the refuel floor to withstand tomado load!.T conditions. The second was a damaged secondary containment penetration seat between the Reactor Water Cleanup (RWCU) Heat Exchanger Room and the pipe chase to the Cleanup Phase Separator Tank Room. Each will be explained in detail below.
Analyses performed to resolve a design basis document (DBD) follow on item (FOI)
showed that the Reactor Building steel superstructure above the refuel floor may not be able to withstand the tomado winds described in the licensing basis of the plant. This was not due to degradation, but due to an original design oversight. As a result, NSP decided to upgrade the superstructure via a modification. This modification was performed after the initial structural baseline inspection. However, from a Maintenance Rulo standpoint, this is clearly an original design deficiency. No preventive maintenance activities would have prevented this outcome, and the baseline walkdown would not be expected to identify a design deficiency of this nature. Since the purpose of the Maintenance Rule is to monitor the effectiveness of maintenance, this deficiency is outside the scope of the Maintenance Rule and need not be documented as a deficiency in the Maintenance Rule Structural Monitoring Program. The upgraded superstructure will be inspected for degradation periodically as part of the normal surveillance activities of the Maintenance Rule Structural Monitoring Program just as the original superstructure was inspected.
The damaged penetration seal was discosered on April 19,1996 and a condition report was initiated to document this discovery. Since the primary function of this penetration l
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REPLY TO UNRESOLVED ITEM Attachm:nt B Page 3 August 15,1997 was to provide a secondary containment barrier and the damage was not of a structural nature, the damaged penetration seal would have been counted as a maintenance preventable functional failure (MPFF) against the Secondary Containment System if it had caused secondary containment to be inoperable. However, the seal did not cause a loss of secondary containment. The leakage from this penetration was within the allowed leakage for secondary containment and was included in the leakage measured by Monticello Surveillance Test 0151-1, Secondary Containment Capability Test.
Therefore, this event was not documented in the Maintenance Rule Structural Monitoring Program or in the Maintenance Rule Access Database under the Secondary Containment System.
In summary, neither of these deficiencies were of a type requiring documentation in the Maintenance Rule Structural Monitoring Program
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The inspection report states, The structural engineer stated that a notebook was kept ofidentified deficiencies; however, the inspectors were unclear how this was incorporated into the MR program.
The Structures System Basis Document, Revision 1, states that the civil engineer responsible for the periodic structural inspection maintains a working copy of noted deficiencies including photos, notes, LERs, Condition Reports, etc. for reference in future structural inspections. Although future inspections will review all areas of in-scope structures, the notebook information is intended to ensure that future inspections !
specifically include the areas where deficiencies have already been identified. Specific guidance on what items were to be included in the deficiency notebook was left to the discretion of the civil engineer.
The inspection report states, Credit was taken for structuralinst'ections performed in 1986 as part of the baseline inspections. This was consideredinappropriate since these inspections were performed over 10 years ago and the program required inspecting the condition of major structures on a 5-year frequency.
An evaluation of critical concrete structures was performed in 1986 as part of Monticello's Pilot Pfard License Renewal efforts in cooperation with the Electric Power Research Institute (EPRI) and the U. S. Department of Energy (reference EPRI TR-103842s " Class l Structures License Renewal Industry Report" and NSPE-12-4312
" PLEX Topical Report for Critical Concrete Structures". These evaluations were considered inputs to the structural initial baseline evaluation since they were used to provide insights as to where structural concrete problems may exist. A structural walkdown by a registered civil engineer was completed in June 1996 of all structures included within the scope of the Maintenance Rule at that time. This walkdown, using the inputs from the 1986 evaluations, fulfilled the " initial baseline" inspection requirement for the in-scope structures as discussed in NEl 96-03.
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<3' REPLYTO UNRESOLVED ITEM Att chm:nt B Page 4 g August 15,1997 l
The Monticello Maintenance Rule Program Document, Eh"-05.02.01, Revision 1, states in Section 6.4 that the initial baseline is comprised of both the 1986 evaluations and the walkdown completed in June of 1996. The Structures System Basis Document, Revision 1, incorrectly states that the 1986 reviews themselves will be used
. as the initial baseline inspection although both the 1986 evaluations and the 1996 walkdown are discussed in detail. NSP acknowledges that these documents do not provide a clear understanding of what comprised the initial baseline inspection. These documents will be revised to clanfy this issue as stated earlier in this response.
The inspection report states, Regulatory Guide 1.160, Revision 2, stated that a structure would be considered (a)(1) if either (1) degradation was to the extent that the structure may not meet its design basis or (2) the structure had degraded to the extent, that, if the degradation were allowed to continue uncorrected until the next normally scheduled assessment, the structure may not meet its design basis. .
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The program did not appear to require placing a structure into (a)(1) based on case (2). The licensee stated that the program would be revised to address this issue.
The performance criteria section of the Structures System Basis Document. Revision 1, defines the classification " acceptable with deficiencies" as structures which are capable of performing their structural functions...but are degraded or have deficiencies which could deteriorate to an unacceptable condition if not analyzed or corrected prior to the next scheduled examination. The basis document goes on to require that any structures identified as being " acceptable with deficiencies" be reviewed by the Maintenance Rule Expert Panel for final (a)(1)/(a)(2) determination and appropriate goal setting action plans. The Monticello Maintenance Rule Program Document, EWl-05.02.01, Revision 1, Section 6.4, states, "A structure should be considered for (a)(1)
status if it is listed as " unacceptable" or if it is exhibiting a trend that will lead to
" unacceptable" status." These examples indicate that the program did account for placing a structure into (a)(1) based on aase (2) above.
The inspection report states, The structure monitoring procedure did not provide guidance to ensure all areas of a structure were inspected. For example, with regard to tho turbine building -
and the reactor building, it was unclear how each room or zone within these buildings were inspected. The procedure also did not give any guidance as to what should be inspected (e.g., component supports, block walls, roofs, structural steel) or criteria defining what was acceptable for these inspections.
Monticello Surveillance Procedure 1385, Periodic Structural inspection, Revision 0, listed the structures to be inspected in Table 1, inspection Results. By listing the structure in this table, it was understood that the entire structure would be inspected by the civil engineer performing the inspection. The surveillance also specifically listed
- concrete, masonry walls, structural steel, roof systems, siding, windows / doors, earthen structures / dams, settlement, and structural / seismic gaps as items to be inspected.
Defining what was an acceptable deficiency or defect was left to the expertise of the
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- ' * REPLY TO UNRESOLVED ITEM Attchm:nt B Page5 August 15,1997 civil engineer. For this specific reason, a registered professional engineer in the state of Minnesota was a mandatory qualification for the individual performing the inspection.
Surveillance Procedure 1385 will be revised as discussed earlier in this response.
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