ML20140E388

Erosion/Corrosion Program Assessment Rept

ML20140E388
Person / Time
Site:	Fort Calhoun
Issue date:	05/02/1997
From:	Dietrich N, Hopkins L, Younger C OMAHA PUBLIC POWER DISTRICT
To:
Shared Package
ML20140E365	List: 05000285/LER-1997-003, Forwards Assessments Containing OPPD Internal Findings & Recommendations Re Extraction Steam Line Rupture Event That Occurred on 970421.Commitments Made by Util Re LER-97-003, Also Encl ML20140E370 ML20140E380 ML20140E388
References
NUDOCS 9706120035
Download: ML20140E388 (24)

Text

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• r ir Attachment 4 Fort Calhoun Station I

Erosion / Corrosion Program Assessment Report, dated May 2,1997 l

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i 9706120035 970604 t PDR ADOCK 05000285-PDR,

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t FORT CALHOUN STATION EROSION / CORROSION PROGRAM ~

ASSESSMENT REPORT 1 .'

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. _l_ e '

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%Y ,1 L P. Hopkins

&L I CraigY%n[r(S(P)

C BS& I Ned Dietrich (DE&S)

Gus Yandall"(iiepresentinh EPRI) ,

C6M O Ow d. A. f~.tk .

David Smith '(DPC):

Approved:

hh 1 'Taylo[

$eK."GasperCo-TeamLeader/ -Team Leader j '

l m dud lY ack L. Skiles YA QNf Sudesh K. Gambhir

[Co-TeamLeader, Sponsor f

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[ FORT CALHOUN STATION EROSION / CORROSION PROGRAM .  !

ASSESSMENT REPORT ,

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I EXECUTIVE SuiNARY (Prepared by Assessment Co Team Leaders) l On approximately April 24, 1997. an assessment team was assembled to review the Fort Calhoun Station Erosion / Corrosion Program. The assessment team also  ;

l reviewed the inspection scope of the High Pressure Extraction Steam System'.' The assessment team was conrnissioned as a result of the April 21, 1997. failure on  :

the fourth stage High Pressure Extraction Steam System elbow No. 5-25. The team ,

consisted of OPPD personnel, and industry representatives from EPRI. South Texas ,

Project. Altos Engineering. Duke Power and Duke Engineering. The assessment was  !

intended to review the Fort Calhoun Station Program against industry practices {

and NSAC-202L Rev.1. A separate review was performed on six additional systems  ;

against industry experience, ie.. Heater Drains. Feedwater Condensate. Steam  ;

Generator Blowdown. Extraction System and Steam Dump Bypass and is addressed  ;

, under separate cover. .l l As a result of the assessment, the team identified program weaknesses and program  ;

strengths. The assessment team categorized the results of the assessment in terms ,

of findings, recommendations, and strengths. The findings were further divided )

to identify issues that should be addressed prior to plant start-up. completion -

prior to start-up from the 1998 Outage and those that were considered long term.

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The assessment team identified 18 findings. 31 recommendations. and 6 strengths .

in the OPPD Program. A review of the assessment concludes that there may have ,

been two contributing factors to the inability of the Fort Calhoun Station to ,

identify the severe degradation in S-25. Consequently. OPPD missed the  :

opportunity to identify the excessive wear at the S-25 elbow. This opportunity  ;

was missed by not inspecting the downstream elbow (S-25) as a consequence of an  ;

upstream failure (this information was not readily available at the time  ;

CHECWORKS models were developed). The report also indicates that OPPD has consistently missed the opportunity to identify high priority (wear) systems by not using the plant . event database information maintained by CHUG and by not aggressively pursuing the changeout of the existing carbon steel material with higher wear resistant material.

i A review of the report findings coupled with the corrective actions taken as a consequence of the failure, and those actions yet to be completed are adequate j to significantly reduce the risk of additional unanticipated failures.'

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FORT CALHOUN STATION I'

, L i EROSION / CORROSION PROGRAM -

l ASSESSMENT REPORT l  : .

l 1.0 REVIEW OF PROGRAM PLAN AND CONTROLLING PROCEDURES f The Program Basis Document (PBD) and Ultrasonic Inspection of Station Piping l (SS-PM-MX-0800) were evaluated to determine if documents exist that address the Erosion / Corrosion Program objectives, description and responsibility.

The stated objectives of the Erosion / Corrosion Program are addressed in the Program Charter

! section of the PBD. 'Ibese objectives state the necewy requirements to reduce the risk of a l consequential failure due to erosion / corrosion.

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A description of the Erosion / Corrosion Program is found in the Program Plan section of the

! PBD. This description was compared with the description of recommended tasks for an effective Erosion / Corrosion Program in Section 4.0 ofNSAC 202L. The Program Plan lists the  ;

systems evaluated for susceptibility to erosion / corrosion and the basis for exclusion when a system was considered not susceptible. In addition, the Program Plan describes inspection l point selection, gridding of piping / fittings, inspection, evaluation, mplacement processes, and j strategies for the mitigation of eresion/ corrosion. As written, the Program Plan does not l provide a description of how susceptible systems are dispositioned with respect to susceptibility <

l analyses.

Program responsibilities are addressed in the Program Plan section of the PBD. Applicable .

responsibilities are listed for personnel in Maintenance, Special Services Engineering, System l Engineering, Design Engineering, QC, Operations, and Chemistry. The Strategies section of

' I the Progrtm Plan discusses the expectation for communication with the Erosion / Corrosion Engineer about conditions that may affect the erosion / corrosion susceptibility. Such conditions may include line-up changes, abnormal line-ups, unusual noises, valve leakage, steam trap failures, plant modifications, and water chemistry changes. During some maintenance activities, visual access to the inside of a component could also reveal evidence of erosion / corrosion that may not normally be known by the Erosion / Corrosion Engineer. It appears that most communications conceming erosion / corrosion susceptibility are between the Erosion / Corrosion Engineer and the System Engineer. Chemistry is designated as responsible for water chemistry interfacing.

The PBD was reviewed for documentation on how inspection locations are selected. The

! Program Plan within the PBD states the selection ofinspection locations may be accomplished by evaluation of the CHECWORKS (CW) wear rate analysis, industry experience, and previous

! inspection results. Sample expansion is not discussed in the Program Plan. SS-PM-MX-0800

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also addresses inspection selection location. Selection is perf:rmed in accordance with NRC, INPO, and EPRI documents (including NSAC 202L), industry experience, CHECWORKS, and engineering judgement. However, there are no detailed procedures for how the inspection -

l selections should be implemented or documented.

The component gridding process is covered in Quality Control Procedure QCP-332. " Ibis procedure'contains requirements for component reference markings, inspection grid sizes, and inspection coverage area. A review ofoutage inspection photographs confirm the effe.ctiveness of the gridding instructions. 'Ibe grid spacing for 6" c.omponents is slightly over the recommendations in NSAC 202L and should be changed for future inspections. ,

The ultrasonic thickness measurements for erosion / corrosion are performed using Quality Contrcl Procedure QCP-331. This procedure includes detailed instructions for calibration,.

! measurement locations, and process documentation. Measurements are performed by qualiSed and certified ultrasonic technicians. This process meets industry standards.

l The Fort Calhoun Erosion / Corrosion Program's implementing documents were reviewed to determine their adequacy regarding the following Erosion / Corrosion Program tasks:

1. Inspection data evaluation

2. Future trending ofinspection results

3. Dispositioning of evaluation results

4. Sample expansions l

The review of the four above areas used NSAC 202L, Rev.1, as its basis. The following 4 documents were myiewed: l

1. Erosion / Corrosion Program Basis Document

2. SS-PM-MX-0800, " Ultrasonic Inspection ofStation Piping" .

3. QCP-331, " Ultrasonic Thickness Measurementfo.- Erosion / Corrosion "

4. FC-1283, " Erosion / Corrosion Evaluation Form "

5. Technical Reference Manual Vol. I and 2 The Fort Calhoun Erosion / Corrosion Program's implementing documents address the subject  ;

areas, with the exception of future trending ofinspection results. The measured wear determination process does not consistently use industry standards / methods or provide results  !

that are useful for CMECWORKS model calibration. The sample expansion process does not address components upstream of expander / expanding elbows and is not worded consistent with ,

industry practice.

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Stre2gths:  !

S1, Discussion of Program history and inclusion of Outage reports in Program document.

provides valuable Program background information.

1 S2. The program is using a safety factor of 1.25 in data evaluations which is more  ;

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conservative than the industry recommended minimum factor. i l Findings:

l' F1. Procedures should include more specific guidance on how Outage inspection locations j are chosen. (Short Term) l F2. Measured wear determination process should incorporate the following industry practices:

! a) Use of at:cepted practices to determine lifetime component wear (circumferential band, moving blanket, point to point) b) Clarify the use of engineering judgment relative to wear determinations.

c) Process for incorporating measured wear into CHECWORKS models.

(Short Term)

F3. Sample expansion process should be revised to align it with industry standards.

Specific changesinclude:

a) Clarify v;ording for small bore piping.

b) Add requirement for inspecting upse of erpandars/ expanding elbows.

c) Clarify that pressure /tommaure exemption only applies to raw water systems, d) Clarify that expansion is to parallel components in each train.  ;

e) Define the terms " component" and " highest wearing".

f) Specify highest wearing components in the same train. ,,

(Short Term)

Recommendations:

RI. Update PBD to:

- Eliminate duplication

- Remove unnecessary detail

- Make PBD and SS-PM-MX-0800 consistent R2. PBD should describe how susceptible systems are dispositioned with respect to analysis.

R3. Update PBD to enhance communication responsibilities between Operations and Maintenance regarding feedback to Erosion / Corrosion hpaaar.

R4. Provide guidance for documenting rationale for inspecting a specific locati'on.

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! I R5. FC-1283 should be enhanced to address the. f:llowing: I a) Directions forthe use of this form.  ;

b) Direction for what to do when measured minimum wall is inconsistent with -

Tnom l c)- Direction is required for what to do when previous thickness is not available and l

l . Tnomis not used. ,

L d) Step "L.ist expansion of test sites not previously evaluated" should be clarified.  !

. j R6. Correct the following typographical errors in the PBD:  !

a) Delete reference to screening criterion (Section F) i b) Indicate small bore /large bore break is s 2" (Section J)  !

1 R7. SS-FM-MX-0800 should be revised to correct the following typographical errors and )

inconsistencies: I a) Clearly define Ta(Section 2.19) b) Set Oc equal to 1.1 (Section 2.19) 1 c) Make Te/c and H consistent with definitions used on FC-1283 (Section 2.19) i d) Allow use of Tnom below 0.100 for small bore piping (Section 2.18.4) _ j R8. Evaluate using highest allowable value of maximum allowable stress (SE) to eliminate unnecessary conservatism and ensure consistency with CHECWORKS.

L R9. Revise program documents to proceduralize the following:

l a) Trending ofinspectionresults .

L b) Qualitative evaluation ofinWon data c) Evaluation of data to ensure thinning is bounded R10. Review the acceptance criteria (Design Minimum Wall) being used for inspection data evaluations to ensure that OPPD applicable code requireme$s are met. .

I R11. Reduce grid size on 6" components to comply with recommendations in NSAC 202L.

R12. A clear separation should be made in Erosion / Corrosion Program documentation between erosion / corrosion and other wall degradation mechanisms (such as raw water i corrosion).

l 2.0 REVIEW OF SUSCEPTIBILITY EVALUATION The review considered adequacy of the susceptibility criteria, the application of that criteria, the methods of addressing susceptible piping, and documentation of susceptibility' evaluations. l

[ PBD gives the results of a susceptibility evaluation to identify plant systems which are l susceptible to Erosion / Corrosion. The plant systems which were evaluated and which have

! been identified as susceptible are listed. However, documentation of the evaluation'is not 4

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cvailable, thus whether all plant piping ~was considered, and whether the criteria applied in the

. ev:1uation was adequate could not be ce&med.

t The EPRI CHECWORKS computer program was used to model certain piping for susceptibility evaluation. The portion ofsusceptible piping evaluated with CHECWORKS is identified,on P& ids and Isometric drawings in an attached volume to the CHECWORKS analysis results report, of January 17,1995.

Based on an interview with the Erosion / Corrosion Fnpam, it was established that tlie L remaining susceptible piping was evaluated by the Erosion / Corrosion Engineer using

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Erosion / Corrosion experience and engineeringjudgement.

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Findings: -

l l F1. A document is needed to describe and control the identification of susceptible systems.

(Short Term) l F2. A document is needed to describe and control the evaluation of susceptible 's ystems.

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! F3. Upgrade the susceptibility evaluation to ensure the following:

a) Susceptible systems are covered.

j b) Susceptible segments of susceptible systems are identified.

c) Operators input is incorporated.

d) Current susceptibility criteria are applied.

, e) Susceptible segments of susceptible systems need to be addressed.

(Start-up)

Recommendations: ,

l RI. Employ the guidance of NSAC 202L to address susceptible piping that is not suitable for modeling.

R2. Develop complete CHECWORKS models of susceptible piping that is suitable for modeling.

3.0 REVIEW OF PLANT MODELING The plant modeling was reviewed to determine whether:

1. CHECWORKS models are available which cover susceptible systems suitable formodeling l 2. . Model verification has been performed

! 3. Initial models reflect as-built configuration i i

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4. Inplon data is included in the models and utili=d to refina the models

. 5. Models are maintained cunent (error correctisn, chemistry changes, operating hour updates, design changes, repairs and replacements, modeling .

enhancements) l

! 6. Models are controlled -

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Initial mcsiels of water systems were developed with the EPRI CHEC code. During 1993, these l models were updated with the EPRI CHECMATE code and two-phase piping added. The l portion of susceptible piping included in these CHECMATE models are identified an'd l desedbed in P&lDs included in the Technical Manual. Upon review of the P& ids and the

! descriptions in the Technical Manual, it is clear that much of the susceptible piping that is suitable for modeling was not included in these CHECMATE models.

The models are documented in the CHECMATE Two-Phase Erosion-Corrosion Analysis Program report, dated July 13,1993. No inspection data were included in these models. The

, sampled section represented the as-built configuration at that time. The report was vedfied by i the Erosion / Corrosion Engineer.

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i The CHECMATE models were indapandantly reviewed by ABB/Impell, and some 1 recommendations were provided. Based upon an interview with the Erosion / Corrosion Engineer, these recommendations were included in the models but not documented. "Ibere is no documentation that those models were kept current.

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Dudag an EPRI/OPPD tailored collaboration project, the available CHECMATE models were l

j converted by EPRI to the EPRI CHECWORKS code. UT inspection data available at the time l

were added to the models, and the models electronic database and analysis output provided in a letter report. These CHECWORKS models have not been verified. There is no documentation that the CHECWORKS models have been kept current.

l Findings:

F1. ( Current plant CHECWORKS models need to be verified. (Short Term) J F2. Inspection data from 1995 and 1996 outages needs to be incorporated into CHECWORKS models consistent with industry practice. (Short Term)

F3. 'Ibe plant CHECWORKS models need to be updated and controls put in place to document changes. (Short Term) i 1

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4.0 REVIEW OF IMPLEMENTATION OF PROGRAM DOCUMENTS / PROCEDURES The Program Basis Document (PBD), Ultrasonic Inspection of Station Piping -

(SS-PM-MX-0800), Outage Reports, and Technical Reference Manual were evaluated to determine if the selection ofinspection locations is being implemented in accordance ivith program documents. The review used NSAC 202L as its basis.

Implementation ofinspection point selections was discussed with the Erosion / Corrosion Engineer to determine adequacy. 'Ibere are no detailed procedures for inspection point l l selection and documentation is limited for how selection is accomplished for a particular outage s (See F1 and R4 in Section 1). There is a CHECWORKS wear rate analysis report from 1995, but there were no indications on this report as to which components were selected. There is a database listing from the Technical Reference Manual that indicates when certain inspection locations that resulted from industry experience. In the Outage Support sections of the PBD, a list of recommended inspection points is provided for the following outage as a result of inspections during the current outage. A sample of small bore components are selected based on engineeringjudgment.

The Erosion / Corrosion Engineer confirmed verbally that this selection process was performed as stated in the referenced program documents. In summary, the selections are based on l evaluation of the CHECWORKS wear rate naalysis, industry experience, previous inspection l

results, and engineering judgement. NSAC 202L recommends that piping and components downstream of replaced components be inspected.

t The implementation of the quality control procedure for erosion / corrosion (QCP-332) was compared to a sample of the outage data from 1996 and the current work in the field. Some j i discrepancies were ideutified in the 1996 data conceming the extent of downstream canponera coverage. It could not be verified if the area in question was obstructed, or if there were other reasons for not continuing the grid. The noted components included inspection areas beyond .

the current industry recommendations, but did not meet the coverage as specified in the procedure. Grids reviewed were neatly applied and meet the grid spacing requirements.

A limited review of the ultrasonic thickness measurement process was performed by observing l the inspection work on a removed component in the Maintenance Shop Area. Additional information was obtained by interviewing Rick Ruhge of the QC Department. The inspection l observed, and the interview information, indicate that the program is meeting procedural and l industry standards in this area.

The Fort Calhoun Erosion / Corrosion Program was reviewed to determine if the program as implemented met program requirements and industry standards in the following areas:

. Evaluation ofInspection Data

! . Sample expansion

- Repairs and Replacements

. Documentation of Outage Inspection Results j 7 May 2,1997 l

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. Traceability and Retrievability cfInf:rmati:n

. . Independent Verification cf calculati:ns and results l

As noted previously, differences exist between Fort Calhoun's procedures in these areas and industry standards. 'Ibere are additional deviations that were identified when the -

implementation of these processes was reviewed. This review was performed using a sampling of1996 inspection data packages.

l A review was performed on Erosion / Corrosion Program activities with respect to baseline inspection of new/ replaced swyGble components.Section IV of the PBD provides instruction for performing baseline inspection of new/ replaced components which are still susceptible to erosion / corrosion. A sample of replaced components in the 2nd,4th, and 6th stage extraction stream lines were reviewed to ensure compliance with this requirement. No discrepancies were noted.

Strengths:

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S1. Inspection data packages contain detailed information concerning grid installation and i I

layout.

S2. A sound decision was made to replace S-56 during the 1996 Outage.

l Findings:

F1. Review systems to ensure piping and co nponents downstream ofreplaced components have been inspected to ensure industry experience has been addressed. (Start _up) l l

F2. Component S-56 appears to have been installed without the required re' mforcing pad.

(Documentation is being pursued by OPPD personnel that may resolve this issue.) ,

(Start-up)

F3. Packages from the 1996 Outage have not been reviewed (Examples: S-4, S-33, D-26A, S-38, D-84A, D-213) as of 4/30/97. (Start-up)

F4. Components displaying significant wear should be re-evaluated using industry standard techniques. (Examples: S-73, S-74, S-66 and S-63) (Start-up)

F5. Documentation should be provided when grid refinement or scanning is performed l when significant erosion / corrosion is found. (Short Term)

F6. The ivion data evaluation for components with PASS 2 CHECWORKS analysis did not consider current predicted wear rates. (Short Term)

F7. Data or evaluations could not be found for the some 1996 inspection locations.

(Examples: S-57,S-80,S-92)(StartUp) t 8 May 2,1997 l

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Fg. The program does not appear to employ verificati:n cf many elements and a formal l . process f:r changing program elements does not appear to exist. (Examples:

CHECWORKS model changes, Erosion / Corrosion Program General Information Table, Erosion / Corrosion Program Technical Data Review.) (Short Term)

! F9. A review of high priority systems (Feedwater, Steam Dump and Bypass, Blowdown, -

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l Extraction Steam, Condensate, and Heater Drains) should be performed to ensure locations that' industry experience has shown to be potentially susceptible have been addressed. (Start-up)

L I Recommendations:

• l RI. The isometric drawings identifying CHECWORKS component identiners are vital

tools. A set'of these drawings should be placed in retrievable storage and a second set l should be used as a working copy.

( R2. Sample expansions should not rely excessively on older inspections and should l aggressively seek to ensure thinning is bounded.  ;

1 R3. Sample expansion on tee branches need to be performed on the train containing the branch. .

l R4. The inspection data evaluation process should address how to handle components with readings greater than Tnom. ,

R5. Any exceptions to the grid procedures should be noted on the layout diagram provided  ;

in the outage summary notebook.

R6. The CHECWORKS Program should be used to perform inspection data evaluation. ,

l R7. Each inspection data package should include a printout showing the inspection data

! matrix.

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5.0 COMMUNICATIONS BETWEEN DEPARTMENTS NSAC 202L references that adequate and formal communications should exist between various groups. The OPPD PBD - Erosion / Corrosion Control, Page IV-13, Section 2, titled " Increased Communication" states that "any changes in the physical or chemical state of the plant that may impact the erosion / corrosion rates should be communicated to the Erosion / Corrosion Control Program Engineer for evaluation . . ."

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1) thni*y (('hani*y changes, feed water iron transport, chemistry history) l 4

, Chemistry data is forwarded to the Erosion / Corrosion Engineer via FC-215 " Daily -

Secondary Chemistry Summary Report" and FC-259 " Secondary Chemistry Monthly Summary Report". This information is reviewed and filed by the Erosion / Corrosion Rnfam.

2) Plant Modific'ation (Design changes, material changes)

Discussions with the Special Services Engineering (SSE) Program Manager determined that Field Change Engineering Notices (FC ECNs) and modifications are revie'wed during the closure process for issues that may effect erosion / corrosion. Any items identified that may apply to the Erosion / Corrosion Engineer are forwarded to that individual for review and action. Substitute Replacement Item Engineering Change Notices (SRI ECNs), Knein-ing Assistance Request configuration changes (Procedure GEI-35) or Non-CQE Maintanane, Work Documents (MWDs) are not reviewed for this type ofissue by Special Services Engin-ing. During closure review of MWDs, issues ofinterest may be identified by System Engineering personnel and then forwarded to ,

the Erosion / Corrosion Rnaine .

3) Operations (line up changes, abnormal lineups, unusual noises)

No formal lines of communication exist between Operations and the Erosion / Corrosion Engineer. Information is generally provided to the Erosion / Corrosion Engiam via .

System Engineering. Reference Memo PED-SSE-93-0788.

4) Maintenance (leaks, temporary repairs, unusual visual indications)

The Erosion / Corrosion Engineer does not review normal emergent maintenance ,

activities. Input is dependent on System Eng*meering or a " heads up" from maintenance personnel.

5) Outage Organization, Planning and Scheduling l

Discussion with Erosion / Corrosion Engineer identified that to his knowledge no MWDs j relevant to the Erosion / Corrosion project have been deleted from outages in recent times (from 1990 to present). Erosion / Corrosion Engineer should ensure that project I requirements, i.e., MWDs and other resources are identified as per requirements of SO-104 " Outage Planning and Execution" i

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%J.um , *4,a.+ 2-+4 JS 4 s Ae-.$.ii-m.-Ah,J , h 4 AawP2>d K+--4-.J--AJ4 tem 4J.#544-44 ->sJ- -dJ4AA & d-E--&J 4--A-e-h.hMhe#m J*aA.a.4m.JA.S_.A, .2 hw 22h p_ 4 S a._a.,: 2 44 _f,.4_.

l Recommend ti:ns:

RI. Although it appears that informal communication does exist between various .

departments and the Erosion / Corrosion Engineer the Erosion / Corrosion Engineer should perform a review of emergent MWRs via the Daily Emergent list. Review of this list should give a heads up to any developing system abnormalities.

R2. Consider strengthening the closure review of SRI ECNs, EARS and MWDs to identify any issue of concern to the Erosion /Cormsion Engineer.

R3. Consider revising FC-1282 (Outage Scope Change / Addition Request) to ensure that requests for deletions and additions to outages are properly evaluated for Erosion / Corrosion scope.

R4. Consider adding feedwater iron transport information to FC-259.

6.0 TRAINING AND QUALIFICATIONS FAC personnel arejudged to be well trained and qualified for assigned tasks. However, participation in industry expcnence sharing has been somewhat limited.

( Strength:

S1. The OPPD, EPRI, ABB/Impell and CSI staff who have developed and verified plant models are well trained, and have good experience. Special classes have been l

conducted on site for plant personnel, and outside analysts have attended EPRI classes or have extensive experience.

Recommen:lations: j l

RI. OPPD is a member of the CHECWORKS Users Group (CHUG), but is not an active participant. FAC personnel, especially the Erosion / Corrosion Engineer, should attend the CHUG meetings. These meetings are held twice a year and cover current Erosion / Corrosion technical issues as well as a forum for discussing plant experiences.

l R2. OPPD should participate in the CHUG Plant Experience Database to ensure Erosion / Corrosion staff obtains future updates to this important industry experience l Amtshmee, R3. As a one nuclear unit utility, it is recommended that OPPD considerjoining with a l group of other similar plants at other utilities to form a peer group to share experience )

, and peer assistance.

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. R4. Recommend a program be established to provide fisw ac~ c elerated corrosion sensitivity .

training to applicable plant staff beyond Erosion / Corrosion personnel. This will help to ensure that plant conditions that may affect flow accelerated corrosion are communicated to the Erosion / Corrosion Engineer and incorporated into the Program.

7.0 EQUIPMENT ,

The ct:rrent equipment being utili=d for ultrasonic inspections in the Erosion / Corrosion Program is the Kranth ruer Branson DMS thickness gauge. This equipment provides a digital ,

read-out, a scan presentation, and electronic data storage capabilities. Calibration is required and documented with Quality Control Procedure QCP-331. '

Conclusion:

This equipment meets industry standards for thickness inspection technology.

8.0 LONG TERM STRATEGY TO REDUCE PLANT SUSCEPTIBILITY Plant opemting conditions and replacmant practices were reviewed to determine the effectiveness of the plant's long term strategy to reduce plant susceptibility. Changes in station chemistry have reduced wear rates. No evidence of a plan for systematic replacement ofhighly susceptible areas could be found. The plant appears to rely upon component level like for like i replacements. This strategy may not be cost effective.

Strength:

SI. Use of ETA and high feedwater pH have reduced overall plant susceptibility to ..

Erosion / Corrosion. I Recommendation:

RI. Use of resistant materials and systematic replacements should be considered.

9.0 CONTINUOUSIMPROVEMENT To evaluate the continuous improvement of Fort Calhoun's Erosion / Corrosion Program, the following areas were reviewed:

1. Previous assessments

2. Indications ofprogrhm enhancements l

3. ' Management commitment to the program .

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I Previous assessments perfonned by the NRC, INPO, EPRI and a contractor were reviewed.

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. The EPRI assessment was the cnly one that documented the need for substantive program '

enhancements (letter report dated December 24,1992). EPRI recommended enhancing the .

susceptibility evaluation, use of CHECMATE and industry experience, participation in CHUG conferences and modeling of all trains susceptible piping. ,

Other factors including Erosion / Corrosion personnel involvement in indu:try CHUG conferences, management review ofprogram elements and personnel stability were reviewed.

Management has shown a commitment to the Erosion / Corrosion Program at Fort Calhoun.

. Resources have been provided for developing important program elements. The contifinity of Erosion / Corrosion personnel has brought consistency and continuity to the progran for a relatively long time. However, the Program Coordinator has not been a regular participant in

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CHUG conferences. Overall, the program has incorporated enhancements over its life.  ;

Findings: 1 F1. A follow-up assessment should be performed following the next refueling outage to ,

evaluate the effectiveness of program enhancements. (Long Term) )

Recommendations:

R1. The pmgram should incorporate management involvement in important program elements. (Examples: CHECWORKS models, outage inspection scope, outage close-out) 10.0 RESOURCES Not observed.

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Co :lasi:ns, 5

1 The ===e==nent resulted in the following conclusions concerning the Fort Calhoun Station -

Erosion / Corrosion Program:

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1). Program should be revised to comnaensively address susceptible piping.

2) Program should be revised to meet industry standards in the following areas:

a) Utilintion ofindustry experience b) InWon data evaluation l c) Use ofanalyticaltools >

d) Use of systamatic replacements with resistant materials 3

i 3) Procedures should be revised to be comprehensive. I j Major tasks and decisions should be adequately documented.

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.s Attachment 5

-Fort Calhoun Station Self Assessment  :

Erosion / Corrosion Program Team Findings,  ;

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R6 May 9, 1997 Fort Calhoun Station SELF ASSESSMENT Erosion / Corrosion Program Team Findings 4

Start Up Issues Responsible Corrective Actions Completion Group Date

1. Start Up Issues A. Upgrade the susceptibility evaluation to ensure B. Lisowyj A Restart FAC Susceptib'ility 05/08/97 (Should be the following: R. Aleksick Review was performed to define Complete addressed prior a) Susceptible systems are covered. D. Rollins the scope of the FAC Closure to restart from b) Susceptible segments of susceptible systems susceptible piping. As a Memo current Forced are identified. result. the following FC-0019-17 Outage.) c) Operators input is incorporated. additional lines were added to Section 2.0. F3 d) Current susceptibility criteria are applied. the program: Seal Steam e) Susceptible segments of susceptible systems (entire system). S/G Blowdown need to be addressed. (suction / discharge of BD transfer pumps). Condensate Provide NRC the analysis and justification for Recirculation (recirc.). Steam not test. Traps and Drains. Complete any additional needed inspections Pre Start-up.

Continue review to include lines such as small bore.

Section 4.0. F1 B. Review systems to ensure piping and components R. Ruhge Review MW0s. Mods. past 05/05/97 downstream of replaced components have been R. Frakes inspection data to determine Complete inspected to ensure industry experience has been K. Hyde inspected location. Perform Closure addressed. Document report. an inspection not previously Memo EOS-Followup justification of why exclude in the past completed. MWO 971649 SSE-97-065 to provide to NRC later. (Complete)

Section 4.0. F2 C. Component S-56 appears to have been installed R. Jaworski Inspect S-56 and documentation 05/08/97 without the required reinforcing pad. K. Woods to determine thickness of Complete (Documentation is being pursued by OPPD personnel component. Modify i f Closure that may resolve this issue.) (Prior to Critical) necessary. Memo EOS-ECN 97-161. CWO 97-037 (Comp.) SSE-97-066

R6 May 9, 1997 Fort Calhoun Station SELF ASSESSMENT Erosion / Corrosion Program Team Findings Start Up Issues Responsible Corrective Actions Completion Group Date Section 4.0 F3 D. Packages from the 1996 Outage have not been D. Rollins Review pkg S-4. S-33. D.-26A. 05/08/97 independently reviewed (Examples: S-4. 5-33. A. Patel S-38. D-84A. D-213 and other Complete D-26A. S-38. D-84A. D-213) as of 4/30/97. (Prior pkgs if identified. Closure to Critical) Memo FC-0020-97 Section 4.0. F4 E. Components displaying significant wear should be N. Dietrich Re-evaluate components using 05/09/97 re-evaluated using industry standard techniques. industry techniques. Identi fy Complete (Examples: S-73. S-74. S-66 and S-63) needed inspections as needed. Closure Provide Technical discussion. Memo FC-0022-97 Section 4.0. F7 F. Data or evaluations could not be found for the D. Rollins Locate documentation and OS/09/97 some 1996 inspection locations. (Examples: S-S7. R. Runge include in database. Complete S-80. 5-92) (Prior to Critical) Closure Memo EOS-SSE-97-068

R6 May 9e 1997 Fort Calhoun Station SELF ASSESSMENT Erosion / Corrosion Program Team Findings Start Up Issues Responsible Corrective Actions Completion Group ~Oate Section 4.0. F9 G. A review of high priority systems (Feedwater. D. Rollins Review the 6 high priorjty 05/08/97 Steam Dump and Bypass. Blowdown. Extraction B. Lisowyj systems and identify points Closure Steam. Condensate, and Heater Drains) should be needing inspection. Complete Memo performed to ensure locations that industry inspections or verify that FC-0021-97 experience has shown to be potentially inspections have been susceptible have been addressed. performed. Complete necessary Meeting on how we came up with these system and repairs / replacements as selection criteria. necessary.

Inspection MWO's:

Complete:

971627(ES-3A) 971629(ES-2E).

971630(ES-2C). 971632(HD-3A.

3B. 3C). 971649(HD-18).

971674(HD-1H). 971703(HD) 971666(SGB-2C)

Repair MWO's:

Complete:

971650(HD-3A). 971651(HD-38).

971652(HD-3C). 971655

m .

R8 rey 21, s997 Fort Calhoun Station SELF ASSESSMENT Erosion / Corrosion Program Team Findings Short Term /Long Term issues Responsible Corrective Actions Conpletion Group Date

2. Short Term issues A. Procedures should include more specific guidance on how B. Lisowyj Provide additional specific guidance 1998 (Should be Outage inspection locations are chosen. Procedure for determining outage inspection Refueling addressed prior to Group locations in the Program Basis Outage restart from the Document (PCB) and other program 1998 Refueling doctanents as needed. .

Outage.)

Section 1.0, F1 CIC 970567/01 Section 1.0, F2 8. Measured wear determination process should incorporate the B. Lisowyj Incorporate industry practices for 1998 following industry practices: Procedure measured wear determinations in Refueling a) Use of accepted practices to determine tifetime Group appropriate program doctanents as Outage couponent wear (ciretsnferential band, moving follows:

blanket, point to point) a) Use of accepted practices to b) Clarify the use of engineering judgment relative to determine Lifetime conponent wear determinations, wear (circtsnferential band, c) Process for incorgmreting measured wear into moving blanket, point to point)

CHECWORKS models. b) Clarify the use of engineering judgment relative to wear determinations.

c) Process for incorporating ecasured wear into CHECWORKS modets.

CID 970567/02 Section 1.0, F3 C. Sample expansion process should be revised to align it with B. Lisowyj Revise the sanple expansion process to 1998 industry standards. Specific changes include: be consistent with irriustry standards Refueling a) Clarify wording for small bore piping. as follows: Outage b) Add requirement for inspecting (pstream of a) Clarify wording for smalt bore expanders / expanding elbows. piping.

c) Clarify that pressure /tenperature exenption only b) Add requirement for inspecting applies to raw water systems. tpstream of expanders / expanding d) Clarify that expension is to parattet corponents in elbows.

each train. c) Clarify that e) Define the terms "conpanent" and " highest wearing." pressure / temperature exenption f) Specify highest wearing components in the same only applies to raw water train. systems.

d) Clarify that expansion is to parallel conponents in each train.

e) Define the terms " component" and

" highest wearing."

f) Specify highest wearing components in the same train.

CID 970567/03

R8 R y i's, i997 Fort Cathcun Station SELF ASSESSME::T Erosion / Corrosion Program Team Findings short Term / tong Term Issues Responsible Corrective Actions Corrpt et ion Group Date Section 2.0, F1 D. A doctanent is needed to describe and control the 8. Lisowyj Revise existing doctanents or develop 1998 identification of susceptible systems. Procedure new doctanents to describe and control Refueling Group the process for the identification of Outage susceptibte systems.

CID 970567/04  ;

Section 2.0, F2 E. A doctanent is needed to describe and control the evaluation B. Lisowyj Develop or revise existing procedtres 1998 of susceptible systems. Procedure to describe and control the evaluation Refueling Group of susceptible systems. Outage CID 970567/05 Section 3.0, F1 F. Current plant CHECWORKS models need to be verified. 8. Lisowyj verify the current CHECWORKS model. 1998 Refueling CID 970567/06 Outage section 3.0, F2 G. Inspection data from 1995 and 1996 outages needs to be 8. Lisowyj Input inspection data from 1995 and Prior to incorporated into CHECWORKS models consistent with industry 1996 outages into CHECWORKS model. 1998 practice. Refueling CID 970567/07 Outage Section 3.0, F3 H. The plant CHECWORKS rnodels need to be updated and controls B. Lisowyj Update plant CHECWORKS model and Prior to put in place to doctsnent changes. Procedure revise existing doctanents or develop 1998 Group new doctanents to adninistratively Refutling control revisions to CHECWORKS model. Outage CID 970567/08 Section 4.0, F5 1. Doctsnentation should be provided when grid refinement or B. Lisowyj Revise existing doctanents or create 1998 scanning is performed when significant erosion / corrosion is Procedure new doctanents to require doctanentation Refueling found. Grotp when grid refinement or scanning is Outage performed when significant erosion / corrosion is found.

CID 970567/09 Section 4.0, F6 J. The inspection data evaluation f or conponents with PASS 2 B. Lisowyj Revise inspection data evaluation for 1998 CHECWORKS analysis did not consider current predicted wear cornponents with PASS 2 CHECWORKS Refueling rates. analysis to consider current predicted Outage wear rates.

CID 970567/10

28 May et, e997 Fcrt Calhoun Station SELF ASSESSMENT Erosion / Corrosion Program Team Findings Short Term /Lors Term Issues Responsible Corrective Actions Completion Group Date Section 4.0, F8 K. The program does not appear to enploy verification of many B. Lisowyj Revise doctments or create new 1996 elements and a formal process for changing program elements Procedure documents to strengthen administrative Refueling does not appear to exist. (Exanples: CHECWORKS nodel Group control of verification and changes to Outage changes, Erosion / Corrosion Program General Information Table, program elements (Exanples:

Erosion / Corrosion Program Technical Data Review.) CHECWORKS model enanges, Erosion / Corrosion Program Gerieral Information Table, Erosion / Corrosion Program Technical Data Review.)

CID 970567/11

3. Long Tern Issues A. A follow-up assessment should be performed following the next J. Gasper Perform a formal assessment after 1996 Post 1996 Section 9.0, F1 refueling outage to evaluate the ef fectiveness of program RFO to evaluate the effectiveness of Refueling enhancements program enhancements Outage CID 970567/12 t

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