ML20198A180
| ML20198A180 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 05/09/1986 |
| From: | Gridley R TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8605200355 | |
| Download: ML20198A180 (6) | |
Text
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TENNESSEE VALLEY AUTHORITY CHATTANOOG A. TENNESSEE '37401 SN 1 7,B 5eokout Place
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May 9, 1986 U.S. Nuclear Regulatory Comission RUgion II ATTN:
Dr. J. Nelson Grace, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georr,la 30323
Dear Dr. Grace:
SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 '- NRC-OIE REGION II INSPECTION REPORT 50-321/85-49 AND 50-328/85 REVISED RESPONSE TO VIOLATION is our revised response to violation 50-327, -328/85-49-01.
This is a revision to' our March 7,1986 response to J. A. Olshinski's February 6, 1986 letter to S. A. White which transmiLted IE Inspection Report Nos.
'7 50-327/85-49 and 50-328/85-49 for Sequoyah Nuclear Plant. As stated in my letter to you dated April 15, 1986, we are providing a supplemental response to the subject report. A revised commitment list is provided in enclosure 2.
If you have any questions, please get in touch with R.
E. Alsup at FTS 858-2725.
To the best of my knowledge, I declare the statements contained herein are complete and true.-
I Very truly yours, TENNESSEE LEY AUTHORITY R.
. Gridley Director Nuclear Safety and Licensing Enclosures cc:
Mr. James Taylor, Director (Enclosches) t Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
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A 8605200355 860509 PDR ADOCK 05000327.
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An Equal Opportunity Employer
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ENCLOSURE 1 REVISED RESPONSE - NRC-0IE INSPECTION REPORT NOS. 50-327/85-49 AND 50-328/85-49 JOHN A. OLSHINSKI'S LETTER TO STEVEN A. WHITE DATED FEBRUARY 6, 1986 Violation 50-327/85-49-01 and 50-328/85-49-01 10 CFR 50, Appendix B, Criterion V, requires that activities affecting quality shall be prescribed by documented instructions, procedures, and drawings, and shall be accomplished in accordance with these instructions, procedures, and drawings.
Sequoyah inspection instruction No. 66, inspection of supports, requires that installation conforms to applicable drawings and that all bolts are properly engaged and tightened.
Contrary to the above, between Decerber 16-20, 1985, activities affecting quality had not been accomplished in accordance with documented instructions and drawings in that a field inspection of eidit supports revealed four seismically designed supports with the following deviations from the documented requirements.
1.
Support No. 1-AFDH-244, Rev. 7, pipe clamp bolts on the snubber side was loose.
2.
Support No. 1-AFDH-254, Rev 6, jam nut on the structural attachment side of the sway strut was loose.
3.
Support No. 1-AFDH-411, Rev.
1, item 2 of the vertical rod was bent.
4.
Support No. 2-SIH-444A, Rev.
1, one of the two vertical trapeze rods was disconnected.
This is a Severity Level IV violation (Supplement I).
1.
Admission or Denial of Alleged Violation TVA admits that the violation occurred as stated.
2.
Reason for Violation The violation occurred due to personnel error in that:
a.
The bolts on Support No. 1-AFDH-244 appear to have been loosened while removing the Calcium Silicate insulation.
(Violation Item No. 1) b.
The bent vertical rod on Support No. 1-AFDH-411 appears to have been damaged due to modification and repair work ongoing in the area (scaf folding being braced against rods).
(Violation Item No. 3)
t c.
The vertical trapeze rod on Support No. 2-SIH-444A appears to have been disconnected to provide clearance to perform work on valve FCV-63-4.
(Violation Item No. 4)
No evidence could be found to determine the reason the pipe clamp bolts were loose on Support No. I-AFDH-254.
(Violation Item No. 2) 3.
Corrective Steps Taken and Results Achieved a.
The supports referenced in the notice of violation have been brought up to current inspection standards. A walkdown inspection was performed, in accordance with work requests, in the Auxiliary Building to determine the severity of the problem. The walkdown team consisted of a mechanical engineer from the Fbdifications 6ccup, two craf tsmen, and a Quality Control (QC) inspector.
The scope of the walkdown was to inspect as many accessible supports as possible, to tighten loose bolts and correct bent rods in the presence of a QC inspector, and note any other obvious problems.
Supports inside C-zone areas and supports requiring scaffolding were not included in this inspection.
The observed deficiencies and their dispositions were documented; however, support inspections with no discrepancies were not documented.
Approximately 3000 supports were inspected during the walkdown of which 66 (22 on pipe larger than 2-inch diameter) were found to have loose bolted connections and 10 (7 on pipe larger than 2-inch diameter) with bent or broken rods. Approximately 90 other supports were found to exhibit problems such as chipped grout under base plates, welds needing painted, and apparently missing Unistrut clamps for instrument lines.
j Of the 66 supports found to have loose bolted connections, 30 were due to loose rods. bbdifications and Additions Instruction (FEAI)-il concerning installation and inspection of seismic supports states:
"It is acceptable for a vertical support to have a total gap of 5/32 inch under the pipe, provided that the first vertical support upstream and downstream of the subject support is in contact with the pipe."
This statement implies that a vertical support may exhibit loose rods provided adjacent vertical supports do not exhibit loose rods.
Such was the case on all 30 loose rods found on the walkdown inspection.
In order to enhance the margin available in the supports, the loose rods were tightened during the course of the walkdown, and other noted suspected discrepancies have been dispositioned.
These 66 deficiencies have also been attributed to personnel error.
Ten bent rods were identified. Two of these had scaf folding built around them.
TVA concluded that modification and repair work caused the rod bending.
+
In addition to the approximately 3000 supports previously surveyed in the Auxiliary Building, approximately 1800 manhours have been expended surveying and upgrading supports for tubing and small size pipe both inside and outside containment as described in plant instruction SMI-0-317-25.
Additional activities are planned to enhance the conditions of pipe supports in unit 1.
A documented inspection of approximately 2200 supports inside and outside containment will be conducted. The supports will be inspected for loose fasteners and other features that affect the load-carrying capacity of the supports.
Identified deficiencies will be corrected before restart of the affected unit.
b.
In addition, the Mechanical Maintenance Section reviewed NRC's concern about the "handtight" acceptance criteria of M&AI-9. A determination has been made that the bolted connection acceptance criteria in M&AI-9, s, cp 6.2.3.1, is fully adequate to ensure connections are properly tight at the time the work is performed and inspected.
c.
Also, NRC expressed concern that the Sequoyah Pipe Support Design bbnual (PSDM), Volume 4, indicates that all pipe clamp hex nuts should be replaced with two jam nuts, and none of the supports observed had double jam nut installations.
The Sequoyah Division of Nuclear Engineering (DNE) concurs that the PSDM is a guideline used by pipe support designers, and its intended function is not to define support installation criteria to the field.
Sequoyah installs pipe supports in accordance with criteria speci-fled in G-43, "The Construction Specification for Support and Installation of Piping Systems in Category I Structures." Paragraph 2.7, of G-43, addressed locking devices, but footnote 3 to paragraph 2.7 indicates that locking devices are only required for plants under the jurisdiction of ASME Boiler and Pressure Vessel Code, section III, subsection NF.
Bellefonte Nuclear Plant is the first plant under the jurisdiction of subsection NF.
Therefore, para graph 2.7, of G-43, is not applicable to Sequoyah.
o' 4.
Corrective Steps Taken to Avoid Further Violation I
a.
All modification and maintenance carpenters were instructed l
in the requirements of Hazard Control Instruction (HCI)-M2 as it applies to scaf folds supported from CSSC equipment with special emphasis on hangers.
b.
TVA's Employee Concern Program emphasizes that employees are obligated to report items found to be out of compliance with specifications or procedures. This has been explained to all site employees.
The periodic performance of Surveillance Instruction (SI)-114, c.
"Preservice Baseline Inspection for Tennessee Valley Authority Sequoyah Nuclear Plant," SI-114.1, "ASME Section XI In-Service Inspection Program Unit 1," and SI-114.2, "In-Service Inspection
s Program for Tennessee Valley Authority Sequoyah Nuclear Plant Unit 2 Only," will ensure that any loose fasteners on code class I, II, and III pipe supports will be identified. The implementing Inspection Instruction NVT-1, of Technical Instruction (TI)-51, i
" Assignment of Detailed Test Methods and Responsibility for Non-Destructive Testing," goes beyond the normal scope of ASME, section XI, in that base plates and anchorage are included.
SI-162.1,
" Snubbers Visual Inspection (Hydraulic and bkchanical)," will ensure
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f that loose fasteners on safety-related snubbers will be identified.
The sis require checking for loose fasteners and initiating work requests to correct the problem. Field Change Request (FCR)-4093 has been initiated to add a note to the 47A050 series, hanger installation notes, to allow the plant staff to take remedial actions for loose fasteners. After the revision to drawing l'
47A050 is issued, Mechanical Maintenance will take action (after approval by the DNE) to secure any identified loose support fasteners with an appropriate locking device unless an evaluation i
determines the locking device is not necessary. As an alternative, I
an approved locking device may be installed at the discretion of the cognizant engineer, foreman, or craf tsman, and an evaluation is not required.
This action will be taken whether the loose fasteners are found during surveillance or maintenance activities.
a The information containe'd in the plant instruction to ensure comm pliance and in 47A050's note will be included in NVT-1 to ensure that In-Service Inspection Section is informed concerning require-ments for locking devices. NVT-1 will be revised by September 5, 2
1986.
5.
Date When Full Compliance Will Be Achieved The plant was in full compliance on February 24, 1986. However, as j'
stated in sections 3 and 4 above, a documented walkdown will be performed (including correction of identified deficiencies) before the restart of the affected unit, and NVT-1 will be revised by September 5, 1986.
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ENCLOSURE 2 COMMITMENTS MADE IN RESPONSE TO 50-327, -328/85-49 1.
By September 5, 1986 revise inspection procedure NVT-1 to ensure that the inservice inspection section is informed, concerning requirements for locking devices. The revision will reflect changes to add a note to 47A050 series hanger installation note pursuant to Field Change Request FCR 4093.
2.
By April 30, 1986, Modifications carpenters are to be instructed in the requirements of Hazard Control Instruction (HCI-M2) as it applies to scaffolds from CSSC equipment, with specific emphasis on hangers.
3.
By April 30, 1986, Maintenance carpenters are to be instructed in the requirements of Hazard Control Instruction (HCI-M2) as it applies to scaffolds from CSSC equipment, with specific emphasis on hangers.
4.
Before the restart of the affected unit, a documented walkdown will be performed (including correction of identified deficiencies).
.