ML20215M934
| ML20215M934 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 10/23/1986 |
| From: | Foster D GEORGIA POWER CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-PT21-86-346-000 GN-1120, PT21-86-346, PT21-86-346-000, NUDOCS 8611030504 | |
| Download: ML20215M934 (11) | |
Text
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Georgia Power cornpany
- Fbst Office Box 282 Waynesboro, Georgia 30830 Telephone 404 554 9961. Ext. 3360 404124-8114. Ext. 3360 L
- o. o.ro.i. "3
" 0CT 27 P 2 : d 7:neGeorgiaPower Q* ,P'"'y' p ,' sourhern eiectre systern October 23, 1986 United States Nuclear Regulatory Commission f Region II File: X7BG03-M93 Suite 2900 Log: GN-1120 101 Marietta Street, Northwest Atlanta, Georgia 30323
Reference:
Vogtle Electric Generating Plant-Units 1 and 2; 50-424, 50-425; Process and Root-Vent-Drain Valves; Letter GN-968, dated 6/26/86; Letter GN-1095, dated 10/2/86.
Attention: Mr. J. Nelson Grace In previous correspondence, Georgia Power Company described a potentially reportable concern whereby some process and root-vent-drain valves may not have been installed in accordance with design requirements.
Georgia Power Company has completed its evaluation and determined that this condition is reportable pursuant to the requirements of 10 CFR 50.55(e) and 10 CFR 21. Based upon NRC guidance in NUREG-0302, Revision 1, and other NRC correspondence, Georgia Power Company is reporting this condition pursuant to the reporting requirements of Part 10 CFR 50.55(e). A summary of our evaluation is attached.
This response contains no proprietary information and may be placed in the NRC Public Document Room.
Yours truly,
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D. O. Foster .
REF/D0F/tdm xc: U. S. Nuclear Regulatory Commission Document Control Desk Washington, D. C. 20555 H. G. Baker R. A. Thomas L. T. Gucwa J. P. O'Reilly D. R. Altman C. W. Hayes G. F. Head P. R. Bemis G. A. McCarley R. E. Conway J. A. Bailey R. W. McManus J. T. Beckham 0. Batum D. S. Read R. H. Pinson G. Bockhold Sr. Resident (NRC)
P. D. Rice C. E. Belflower C. C. Garrett (0PC)
B. M. Guthrie J. F. D'Amico J. E. Joiner (TSLA)
D. E. Dutton E. D. Groover D. Feig (GANE) O h 861023 S kogh 05000424 '
. r EVALUATION OF A POTENTIALLY REPORTABLE CONDITION PROCESS AND ROOT-VENT-DRAIN VALVES Initial Report: On February 3,1986, Mr. R. E. Folker, Vogtle Project Quality Assurance Engineer, informed Mr. W. H. Rankin of the USNRC of a potentially reportable condition concerning valves not installed in accordance 'with the design requirements defined in the VEGP Valve Designation List (VDL). This condition was identified by deviation report DR# MD-8515, which reported a discrepancy between the Quantity Tracking System (QTS) report and the Valve Designation Lists. In subsequent correspondence, Georgia . Power Company indicated the NRC could expect to be informed of the evaluation of this condition by October 24, 1986.
Background Information: The design requirements for VEGP valves are defined on piping and instrumentation drawings (P&ID). These drawings are the basis for producing piping orthographic drawings (0RTH0); piping isometric drawings (IS0); the roots, vents, drains, and Instrument Control Valve Designation List (RVDL) and the Valve Designation List (VDL).
The valve design requirements are entered in the VDL/RVDL under a unique valve tag number, and this tag number is assigned to each valve at the time of issue for installation. These valve design requirements are also electronically transferred to the requirements file of the site quantity tracking system (QTS). A second file in the QTS, the inventory file, contains a record of valve requisition data.
Deviation Report DR# MD-8515 was initiated on September 13, 1985, to address the concern that as-installed valves may not meet the design requirements in the VDL/RVDL. This concern was raised as a result of a computer comparison of valve purchase order numbers in the inventory file and the requirements file of the QTS. A total of 2,775 valves for Units 1 & 2 and Common were identified in this comparison and the following data were extracted for these valves:
Purchase order number and item number Mark number Attachment code Project class Size .
An engineering evaluation of the 2,775 valves determined that the discrepancies associated with only 48 valves involved potential departures from design requirements. A walkdown of each of these 48 valves was performed to verify their as-installed condition. The results of the walkdown demonstrated that only 9 of these 48 valves were not installed in accordance with the design requirements in the latest version of the VDL/RVDL. A safety evaluation of these 9 valves is described in Section 7.0.
A special team consisting of representatives from Georgia Power Company (GPC), Bechtel Power Corporation (BPC), and Pullman Power Products
O (PPP) was then formed to assess the concern regarding valve installation on a generic basis. A representative sample of 1,772 safety and nonsafety-related valves in the Unit No. 1 Auxiliary and Containment buildings were selected for walkdown to determine wbether the installed valve was identical to the one shown on the valve travel card and if it met the design requirements in the latest issue of the VDL/RVDL.
In addition, a walkdown was performed for 206 valves within the Unit 1 primary hydro test boundary.
The valve travel card is a controlled document and is maintained by GPC at the warehouse. It provides a record of the serial numbar and the design data of the valve issued for installation.
The walkdown of these 1,772 valves found 157 variations between the as-installed valves and the VDL/RVDL. An engineering evaluation of these variations determined that no physical rework or replacement is required. See Table 1 for a description of the variations.
The walkdown of the 206 valves within the primary hydrotest boundary found 68 variations. An engineering evaluation of these variations also determined that no physical rework or replacement is required.
See Table 2 for a description of the variations.
As a result of the walkdown, the special team concluded the following:
- a. Only minor anomalies were discovered in the material control system at the site. No further valve walkdowns were required.
- b. The QTS computer file, which is an uncontrolled progress tracking document showing the status of the issued valve, is not as reliable as the valve travel card.
- c. The majority of variations between the valve requirements in the VDL/RVDL and the installed condition resulted from two areas.
First, a past warehouse practice of issuing valves by mark number with only secondary concern for the purchase order item number ,
and vendor, and because of revisions to the VDL/RVDL after the valve was issued for installation.
i The special team report, which includes a list of the valves walked down, is shown in project document log PFE-12901 and is available for review at the jobsite.
Based on the review by the special team, the following steps were taken to determine whether installed valves met the design requirements for the tag numbers shown in the latest issue of the VDL/RVDL:
- 1. Establish that the valve travel card reflects the type of valve installed.
As described above, a walkdown inspection for a representative i sample of 1,772 valves was performed by the special team. The
! basis of the sample is as follows:
Approximately 3,500 isometric drawings cover piping systems in the Auxiliary and Containment buildings at VEGP. 1,000 of these isometric drawings were chosen to include a variety of systems and sizes of valves. A total of 2,000 valves were then selected at random from the isometric drawings to assess whether or not the valve travel card reflects the type of valve installed. The number of valves actually inspected by walkdown was 1,772. The rerr.aining 228 valves from the random sample list were located in areas with limited physical access and hence were not walked down. Inspection of the 1,772 valves demonstrated that each valve travel card reflects the type of valve installed. Therefore, in a sample of 1,772 valves examined, zero were found to be discrepant (i.e., all installed valves conformed to the design data on the valve travel card). This provides higher than 95 percent confidence that greater than 95 percent of all valves in the Auxiliary and Containment buildings are installed in conformance with design data on the valve travel card.
Additionally, because a representative cross section of systems and valve sizes were examined during the walkdown program, findings for valves in the Auxiliary and Containment buildings can be inferred to cover all installed valves in all of the buildings.
Therefore, the walkdown demonstrates with a high level of confidence that the valve travel card accurately reflects the type of valve installed.
- 2. Update the QTS inventory file to reflect the design data shown in the valve travel card for all issued valves.
GPC corrected the QTS Inventory File based on the design data on the valve travel card, which provides traceability of valves by their unique tag number.
- 3. Compare the design data in the QTS inventory file and the design requirements in the VDL/RVDL and identify all inconsister.cies in a valve exception report.
! A computer comparison was made between the inventory and l requirements file of the QTS and a valve exception report was generated. This computer printout (file no. SMULT71L dated July 17 , 1986) listed 1,586 safety-related and 2,926 nonsafety-related valves with one or more inconsistencies in valve size, mark number, attachment code, project class, ANSI rating, type, and specification.
- 4. Evaluate the valve exception report to determine whether the installed valve meets the design requirements in the latest issue of the VDL/RVDL.
The engineering evaluation of the valve exception report concluded that discrepancies found in the following five (5) additional valves may have an impact on plant safety:
1-1208-U4-468 2-1214-U4-035 l
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2-1214-U4-036 2-1214-U4-041 2-1215-U4-067 See Table 3 for a review of the inconsistencies in the valve exception report and their basis of acceptance.
Engineering Evaluation: An evaluation of 9 discrepant valves identified by DR MD-8515 and the additional 5 discrepant valves identified by the valve exception report was performed to determine the impact on the plant had the condition pone uncorrected. The following represents the results of the evaluation
- 1. Drain System Isolation Valves (10 valves)
The valves in this category are:
1/2-1214-U4-035, 036 and 041; 1/2-1215-04-067 and 221 DR MD-8515 and the valve exception report indicated that these installed floor drain valves were procured seismic category 2 instead of seismic category 1 as specified in the VDL and the P&ID's. This deviation was confirmed by the walkdown inspection.
and/or review of the valve travel cards. An additional deviation report was initiated to address this condition and engineering concluded that the installed valves were adequate for their intended function and would not impact the safety of the plant. This deviation report was dispositioned to "use as is" on the basis that the above valves will maintain pressure integrity and function and meet the Category 1 requirements of the system as demonstrated by seismic calculations.
- 2. Containment Isolation Valves (2 valves)
DR MD-8515 indicated that the installed valves, 1-1222-04-026 and 027, were project class 424 instead of being project class 212 as specified in the VDL. Project class 212 was assigned to these valves to ensure isolation of the containment leak rate test system during a seismic event. An offsite dose analysis for VEGP was performed assuming these valves to be in a locked closed position. Failure of these valves to perform their isolation function during a seismic event or accident condition may lead to a condition that was not analyzed and may impact the safe operation of the plant.
- 3. Valves in the Secondary Boration Path (1 valve)
DR MD-8515 indicated a material deviation in a check valve, 1-1208-U4-483, which is installed in the normal boration path I of the Chemical and Volume Control System (CVCS).
The material for the cap studs and cap stud nuts for this valve is required to be corrosion resistant (ASME SA-453 GR 660) due
to the borated water environment. The installed material (ASME SA-193 GR B7 and SA-194 GR 2H) was found to be inadequate for this service.
Sudden failure of these components is not expected to occur because they are protected by a seal held in place between the valve body and cap and are not exposed directly to borated water. Furthermore, during maintenance of the seal, the studs would also be inspected and replaced if the seal was broken and corrosion effects were noted. Therefore, the potential exposure of the studs / nuts is considered minimal and catastrophic failure, resulting in the cap separation, is not anticipated. This condition has no implication on plant safety.
- 4. Throttling Valve to Boron Meter (1 valve)
The valve exception report indicated that valve 1-1208-U4-468 was installed as a 3/4" packless metal diaphragm valve (mark no.
320) instead of 3/4" conventional globe valve (mark no. 329).
This valve is project class 212 and its function is to throttle the flow to a nonsafety related boron meter.
Continuous throttling will cause cavitation and chattering of the disc of the metal diaphragm valve resulting in erratic flow to the boron meter and incorrect measurement. Although prolonged chattering of the disc may result in its eventual failure, the be contained within the pressure boundary 1
fluid medium will components of the valve.
Since the boron meter does not perform a safety related function, this condition has no implication on plant safety.
Evaluation of Quality Assurance Program Breakdown: While there were variations between various documents pertaining to the design, procurement, and installation of the subject valves, the results of the very extensive walkdown and documentation comparison determined that only 14 as-installed valves did not meet the design requirements and only two of the discrepancies could affect safety. The deficiency, therefore, is not considered to be a significant quality assurance program breakdown.
Conclusion:
Based on the results of the above engineering evaluation i (item 2), the plant safety could have been impacted had the condition gone uncorrected. Therefore, Georgia Power Company has concluded that a reportable condition as defined by the reporting criteria of Part
! 10CFR50.55(e) and Part 10CFR21 does exist. Based on the guidance in i
NUREG-0302, Revision 1, concerning duplicate reporting of an event, Georgia Power Company is reporting this event per the criteria of Part 10CFR50.55(e).
l Corrective Action:
- 1. The two (2) containment isolation valves described in item 2 of the engineering evaluation have been cut out and replaced with
- - - - - - . - . - - - --. n --- -- -- - -c., - , - , - -
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i correct project class 212 valves. This action was tracked by 4
PCW item number 181881-005.
- 2. (ASME SA 193 Grade B7 bolts and SA 194 Grade Bolting 2H nuts )materialhave been replaced with ASME SA 453 Grade 660 material for the valve described in item 3 of the engineering evaluation.
This action was tracked by PCW item number 181881-004.
- 3. The packless metal diaphragm valve has been replaced with a conventional globe valve for the valve described in item 4 of the engineering evaluation. This action was ' tracked by PCW item number 181881-002.
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9 TABLE 1 WALKDOWN OF 1772 VALVES A. Distribution of Valves in Walkdown_
RVDL VDL Q NON-Q Subtotal Q NON-Q Subtotal Valve Distribution (1772 Valves) 0 0 0 161 221 382 Large Bore 428 592 1 020 229 141 370 Small Bore 537 BTI 1,402 78J 141 TT6 Totals Total = 1,772 B. Variations between As-Installed Valve Data and VDL/RVDL RVDL VDL Q NON-Q Subtotal Q NON-Q Subtotal Variation Distribution (157) 56 20 9 29 39 17 Different Vendor (1) 6 8 25 33 Different Mark No. (2) 1 5 0 0 0- 0 3 3 Project Class Downgrade (3) 10 0 10 9 11 20 Different Serial No. (4) 75 Totals lit TJ 37 T6 TT
' IUfAL = 157 CAUSE OF VARIATIONS (1) Different vendor - warehouse substitution and/or VDL revised after issuance of valve to field.
(2) Different mark No. - VDL revised after issuance of valves (26); VDL revised per inaccurate QTS (8); VDL error (2); tag No. change after l
i valve issuance (2); incorrect vendor data tag wired to valve after issuance (1).
(3) Project class downgrade - ISO not revised - previously reported on MD-8515 (1); . warehouse tagging error - pulled incorrect project class (2).
(4) Different serial No. - 30 cases were found were the serial number
'~ of the valve did not correspond to the associated valve travel card.
886MLC
TABLE 2 WALKDOWN OF PRIMARY HYDRO VALVES A. Number of Valves in Walkdown = 206 B. Variations between As-installed Valve Data and VDL/RVDL P.O. item number 49 i
7 Vendor 8
Mark number attachment code Valve serial number J TOTAL 68 i
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TAaLE 3 REVIEW SF VALVE EECEPiltu REPORT SAFETY a m mAE-5AFETT BELATES VALVES BASIS OF ACCEPTAACE (ESTE 1) mei CATEGGRf SF TSTAL 38 ACCEPTAaLE leCONSISTEaCIES OF VALVES a b c d e f g h 1 j k 1 e a o (ESTE 3)
(ESTE 2) (ASTE 2)
VALVE SIZE 321 3 168 112 12 21 5 MARK NUMBER 530 136 1 6 to 138 152 3 11 62 6 5 265 86 2 8 ATTACHMENT 361 2448 51 81 14 267 PROJECT CLASS 2861 14 21 141 ANSI RATING 116 24 4 9 1 4 248 201 5 SPEC /PO 2 1 12 EALVE TYPE 15 15 24 361 370 15 0 71 228 277 5 TOTAL 4512 3 136 266 86 2649.'6 BSTES:
- 1. Basis of Acceptance
- 4. Different size valve issued that meets design requirements.
- b. Issued mark number is acceptable in accordance with the piping material classification or meets design requirements.
- c. Issued valve requires an attachment (Itke reach rod or locking device) that is procured separately and is installed in the field, which denotes the Bechtel specified
- d. Issued valve without attachment code "1" Valve leak tightness is air leak test for containment isolation valves.
assured in the field during local leak rate test and/or contefasent integrated leak rate test.
j - . -
j e. Issued valve with equivalast or higher proj2ct' c1:ssificall32 than t*m .
required systes project classificatten. (
1 f. Issued valve with higher pressure rating than the required systes pressure rating.
1 g. Issued valve with lower weight and center of gravity than that used for i
plalag stress analysis. la these cases where the valve weight endler center of gravity is higher, as-built reconcillatlea as regelred la accordance with j project Reference Itaamal. Sectica C 41.g.7 mill assure that piplag stress j
analysis is acceptable.
I h. Valve substitutten of an identical valve by a different vender than
- spec 1fIed.
- 1. 415 levantary file is lacerrect based on a recheck of the valve travel card.
l J. Vend 6r supplied valve as part of an equipment package has ne mark mester and l attachneet code and has alsslag er lacerrect data la the VOL.*
j I k. Issued valve is either surplused (met lasta11edl er is la na abaadened system.
f 1. Issued status of valve is beleg vertfled in the field.
- o. VOL file is lacerrect and is to be updated to reflect the latest j
requirements.
- a. Issued valve meets VOL requirement but shows up as _en esceptica because of
' the cesputer cesgiarlsen (like mark me. 083 vs. 83, or attacheent code "LJIC*
es. *LCJI").
I e. Upgraded seismic category of nea-4 issued valves to meet VOL requirements.
! (4 o f Th e le ve t ve s sJe=te f ica i n fl.a Mark 04 umber CaTaqoraj}
2- 12 t + - u+ - o ss , o 3 6, o 4: a.d 2 - s asy- u+ - os,7, a re Jo seussel in stem i o4 the. bagsviterirq EvolwabQ
! 2. The laceaststencies are broken down late 7 Categories with valve size havlag the highest ranklag and valve type the lowest. If a valve tag number has more than ene inceaststency, the tag awaher with all inceaststencies appears la the valve esceptica report caly once generally under the category havlag a higher ranklag.
) All f aceaststencies f or a given valve tag number were reviewed for acceptahllity and the most appropriate acceptance criteria is assigned la the table.
- 3. The total meeer of (5) wascceptable valves are broken down as fellows:
1 l
dem 4 h Fissg..icerena) EnlacJim)
I Safety Related: Tag # l-1204-04-468 (Se.e usa-safety Related: Tag f A-1423-U4-017, 021, 025; Z-Ig61-U4-081.
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