ML20079F615
| ML20079F615 | |
| Person / Time | |
|---|---|
| Site: | Midland |
| Issue date: | 06/01/1982 |
| From: | Jackie Cook CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| REF-SSINS-6820 17510, IEB-79-02, IEB-79-2, NUDOCS 8206080109 | |
| Download: ML20079F615 (4) | |
Text
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l Consumers Power James W Cook Company v,c, ~,c,n, - ~ym. c#,,
' anl Constmetion oeneral Offices: 1946 West Pernell Road, Jackson, MI 49201 + (517) 7880453 June 1, 1982 Mr J G Keppler, Regional Administrator U3 Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 60137 MIDLNID PROJECT -
DOCKET NOS 50-329 AND 50-330 IE BULLETIN 79-02
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FILE:
0505 12 SERIAL:
17510
References:
CPCo letters to J G Keppler; Midland Project; Docket Nos 50-329, 50-330; IE Bulletin 79-02:
- 1) Serial Hove-195-79; dated July 3, 1979
- 2) Serial Hove-233-79; dated August 15, 1979
- 3) Serial Hove-84-80; dated May 7, 1980 h) Serial 9107; dated June 9,1980
- 5) Serial 10049; dated October 31, 1980
- 6) Serial 11505; dated February 26, 1981
- 7) Serial 1h636; dated December 15, 1981 References 1 through 7 are correspondence which address IE Bulletin 79-02.
References 3 through 7 reported that further evaluations and corrective actions were required to completely address 79-02. The enclosure to this letter provides the latest status of those rer.aining action areas. The paragraphs of this enclosure are numbered the same as reference 7 Either a final response or a status report will be provided by January 30, 1983 WEB /1r Enclo sure CC: Document Control Desk, NRC Washington, DC RJCook, NRC Resident Inspector Midland Nuclear Plant 8206080109 820601 bg 4.
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Scrial 17510 t71658 1.
Anchor Bolt Use Prohibition An agreessent has been reached with the original pipe support
~
a.
design agency to allow a one-time design deviation that per-mits expansion anchor bolts to remain in the first two sup-ports on either side of a pamp, provided the calculated bolt load is 25% or less of the anchor bolt specification allow-able.
pipe supports that do not meet these criteria vill be reworked.
b.
The method of performing baseplate analysis by the primary design agency has been decertzined to be accap~ table.
Bechtel is finalizing and coordinating the documentation of the metbo-dology.
Discrepent pipe support designs issued by the pipe suppcrt c.
design agency and documented on nonconformance reports have been dispositioned.
All pipe support designs issued by the primary pipe support design agency are b-ing rereviewed".for proper anchor bolt usage. This review is being conducted on a rystem turnovar priority basis, with completion expected in December L982.
2.
Determination of Proper Embedment Depth The inspection of anchor botta used for pipe supports is a.
addressed in Section 6.
b.
It has been concluded that no further testing and inspection for embedment depth is required for expansion anchors used on nonpipe-support applications.
This conclusion is based on the results of the reinspections of expansion anchors used on pipe supporta, and besting, ventilating, and air conditioning Saismic Category I support applications.
Reinspection and testing in accordance with project speci-fications (issued to satisfy the requirements of IE Bulle-tin 79-02) for pipe support anchors installed before May 30, 1930, was coupleted. Of 1,631 expansion anchors reinspected, 65 did not meet the requirements for embedment depth.
These results indicate, with a 95% confidence level, that over 95%
of the anchors satisfies the criteria for embedment length.
Additional reinspection and testing of expansion anchors used for besting, ventilating, and air conditioning Sciosic Category I supports was perfortmed.
Of 4,565 expansion anchora reinspected, 72 did not meet the requirements for embedment cepth.
i These results also indicate, with a 95% confidence level, that over 95% of the avhors satisfies the criteria for embedaant depth.
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671658
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Page 2 The controla initiated in May 1980 for length marking and c.
.716aB.
qualie* control inspection (MCAR 31) provide assurance that e,3.g
,e ae,t3,111 oot,oes e,,,31.,,
3.
Demonstration of Achievement of Required Factor of Safety Midland-specific tests to determina the amount of preload a.
remaining in the bolt indicate that an average of 37% of the original preload remains in the bolt af ter 1 yerr. Other tests (References A and B) have established that. che amount of preload on the bolts will not affect the performance of the anchorage. If the initial installation torque on the bolt accomplishes the purpose of setting the wedge, than the ulti-mate capacity of the bolt is not affected by the amount.of pralcad present in the bolt at the time of cyclic loading.
These tests (Rafarances A and B) indicate no anchor pullout failures occurred as a result of cyclic loading and that preload is not required to withstand cyclic loading. A revised response to IE Balletin 79-02 will be sent by July 30, 1982.
b.
An additional static tension test (Reference C) to supple-ment the manufacturer's data was conspitced. The final report, combined with the unaufacturer's data, establishes that all stres of expansion emchors used for pipe supports under the scope of
'IE Bulletin 79-02 on the Midland project met the required factor of safety for pullout.
4.
MCAR Status a.
MCAR 34 Bechtal Management Correceive Action Report (MCAR) 34 final report, concerning installed drop-in anchors, has been issued.
No further new corrective action is required. Required rework is anticipated to be completed in July 1982.
b.
NCAR 31 MCAR 31 Revised final Report, concerning embedment depth of expansion anchors, was issued May 10, 1982 Corrective actions associated with MCAR 31 are complete.
5.
Reportability Review Review of the results of the inapection and tests identified no items with a safety impact.
Results of future analyses will be reviewed for reportability under 10 CTR 50.$5(e).
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Pag 3 3 l
Additional Expansion Anchor Inspectiens laspection of 200% of the accessible pipe support expansion anchora installed before May 30, 1980, is complete. An evaluation of the adequacy of the inaccessible anchors (less than 6.7% for any parameters), based on the inspection results of the accessible anchors, is in process.
Identification and completion of the rework for the inspected anchors will follow.
_Re b rances A.
Teledyne Engineer 2ag Services Technical Report 3501-2 for Utilities /
TES Owners Group, Summary Raport Generic Response to US NRC IE En11stin 79-02 5
cenwealth Edison Company Summary Report, Scatic, Dynamic and Ralaxation Testing of Expansion Anchors in Response to NRC IX Bulletin 79-02, 7/20/81 C.
Final Report on Concrete Erpansion Anchor Static Tension Tests for Bechtel Power Corporation. March 1982. Wiss, Janney, Elstaar and Associates, Inc.
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5/17/2
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