IR 05000237/1985018
| ML17195A788 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 05/08/1985 |
| From: | Danielson D, Yin I NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML17195A787 | List: |
| References | |
| 50-237-85-18, NUDOCS 8505130360 | |
| Download: ML17195A788 (3) | |
Text
U. S. NUCLEAR REGULATORY COMMISSION
REGION III
Report No. 50-237/85018(DRS)
Docket No. 50-237 License No. DPR-19 Licensee:
Commonwealth Edison Company P. 0. Box 767 Chicago, IL 60690 Facility Name:
Dresden Station, Unit 2 Inspection Conducted:
May 2, 1985 Inspector:
Approved By:
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D. H. Danielson, Chief Materials and Processes Section Inspection Summary Inspection on May 2, 1985 (Report No. 50-237/85018(DRS))
Date s/~Jgr Date Areas Inspected:
Review of* main steam transient monitoring system strain gage signal The inspection involved a total of three inspector-hou.rs * onsite by one NRC inspecto Results:
No violations or deviations were identifie (
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- DETAILS Persons Contacted
- J. Achterberg, Technical Staff Supervisor
- W. Pierce, Technical Staff Engineer
- M. Strait, SNED Engineer
- C. E. Beck, SNED Electrical Engineer
- B. Schroeder, Technical Staff.Engineer
- J. Brunner, Assistant Superintendent-Technical Services Wyle Laboratories (Wyle)
- G. Drake, Senior Test Specialist
- Denotes those attending the exit meeting held at the site on May 2, 198.
Functional artd Program Areas Inspected
In accordance with the Region III (RIII) Confirmatory Action Letter 85-04, CECo reported to RIII the strain gage (SG)
~ignals they had recorded for snubber No. 46 on May 2, 198 This SG is one of six SGs installed on the previously damaged main steam (MS) snubbers to provide continuous moni-toring for possible MS transient The inspector reviewed the strip charts, and determined that there had been intermittent opening and then a completely opened electronic circuit indicating instrument hardware failure after 0.5 seconds of recordin However, the cause of the initial 0.5 second activity, whether it was caused by loose wires or by a dynamic load that could damage the SG, was unclea The inspector's review concluded the following: The snubber No. 46 displacement instrument showed that the snubber was not jamme The same displacement instrument did not indicate even the slightest snubber reactio Plant operating data did not show any abnormal indication in terms of a system transient or disturbanc Even if the strip chart print-out is real (signal equivalent to 60 to 80 Kips), the magnitude of the load was probably not sufficient to damage the biological shiel.d wall structure where the snubber was attache Based on the above review, the inspector concurred with CECo that it wa not necessary to inspect the piping during the present Mode 5 condition.
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CECo stated that during the scheduled June 1985 plant shutdown, they will determine the cause of the SG damage and repair or replace the ite The inspector noted that there was the possibility of excessive piping system vibration and that he was interested.in what the licensee actions would be if the SG instrumentation was checked and no defect or damage was foun RIII will followup on the licensee action This is an open item (237 /85018-01). Open Items Open items are matters which have been discussed with the licensee, which will be reviewed further by the inspector, and which will involve some action on the part of the NRC or licensee or bot An open item disclosed during the inspection is discussed in Paragraph.
Exit Interview An exit interview with licensee representatives was conducted on May 2, 1985 to discuss the finding The inspector discussed the likely informational content of the inspection report with regard to documents reviewed by the inspector during the inspectio The licensee did.no identify any such documents as proprietar