IR 05000245/1979013
| ML19208B933 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 07/23/1979 |
| From: | Feil R, Lester Tripp NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML19208B931 | List: |
| References | |
| 50-245-79-13, 50-336-79-17, NUDOCS 7909240182 | |
| Download: ML19208B933 (8) | |
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U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT
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Region I Report No. 79-13 (1) & 79-17 (2)
Docket No. 50-245 (1) & 50-336 (2)
License No. DPR-21 & DPR-65 Priority:
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Category:
C Licensee:
Northeast Nuclear Energy Company Attention: Mr. D. C. Switzer, President P.C. Box 270 Hartford, Connecticut Facility Name: Millstone Nuclear Energy Station, Units 1 & 2 Inspection at: Waterford, Connecticut Inspection conducted: May 14-18, May 29-June 1, 1979 Inspector:
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7 - 2 C-7 7 R. A. Fe.il, Reactor Inspector date signed
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~ Approved by:
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E. E. Trip ~p'
Chief, Engineering Support date signed Section #1,,RC&ES Branch Inspection Sumary:
Inspections on May 14-18, May 29-June 1, 1979 (Report Nos. 50-245/79-13
& 50-336/79-17 Areas Inspected:
Routine, unannounced inspection by a regional based inspector of modifications conducted during the refueling outage.
The inspection consisted of review of QC records, procedures, tests and related activities.
The inspection involved 49.5 inspector hours on site by one NRC regional based inspector.
Results: No items of noncompliance or deviations were identified.
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-2-DETAILS 1.
Persons Contacted Unit 1
- J. Opeka, Station Superintendent K. Thomas, Maintenance Supervisor
- P. Pzrekop, Engineering Supervisor
- M. Bigiarelli, Congnizant Engineer Unit 2
- E. Farrell, Unit Superintendent R. Place, Maintenance Supervisor J. Resetar, Cognizant Engineer The inspector conferred with other licensee personnel during the course of the inspection.
- Denotes those present at exit interview.
2.
Licensee Action on Previous Inspection Findings (Closed) Unresolved Item (50-336/78-16-04) Two seismic restraints not making contact with the spent fuel pool wall.
The inspector reviewed maintenance requests, which were closed out, showing that pressure using a pry bar resulted in the two snubbers making contact with the spent fuel pool wall.
The action was performed by divers on 1/5/79 and 3/14/79.
3.
Tour of the Facilities The inspector toured the work areas for the valve limit switch installation in Unit 2, as well as the safety and reitef valve and the torus area of Unit 1.
All 44 limit switches had been installed and signed off as completed.
Two safety relief valves had been installed at the time of the tour with four remaining to be installed.
Covers were mounted over the inlet and discharge piping where the valves were to be installed.
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Six new T Quenchers had been installed in place of the "Ramsheads" on the downcomers of the safety / relief valves.
No items of noncompliance were identified.
4.
Modifications & Design Changes The inspector reviewed selected records for several modifications and changes made to the facilities during the current refueling outage.
a.
Failure of 4160/480V Transformer on Unit 2 The licensee submitted a Plant Incident Report dated 4/18/79 which stated, in part, that breakers to Vital '3us 22E tripped on loss of 50/51 relays.
The 4160/480V transformer feeding Bus 22E was found smoking.
The licensee replaced the damaged transformer with a like 4160/480V transfomer which fed non-vital Bus 228.
The inspector verified that the transformer had the following name plate date:
Voltage Rating 4160-480Y/277 Class AA Three Phase 60 Hertz KVA Rating 1500 Continuous 120 C Rise Self-Cooled At Over 50 C Ambiant KVARating2000Cogtinuous120CFuture Forced Air Over 50 C Ambient Impedance Volts 7.47% at Rated Volts.
The licensee welded steel pads to the bottom of the replace-ment transformer.
In addition, it was necessary to cut and reweld one phase bus bar in order to place the transformer in position.
The inspector examined weld procedures, welder qualifications, weld specifications, inspection plans and procedures, job order, material receipt and issue forms, and acceptance tests.
The inspector verified that the Plant Operation and Safety Review Committee reviewed the procedure.
The damaged transfomer has been shipped to a GE facility for inspection and analysis.
This item remains unresolved pending review of the analyses of the damage to the transformer.
i2 (50-336/79-17-01)
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Environmental Qualification of Class IE Equipment for Unit 2 IE Bulletin No. 79-01 identified a component which was unqualified for service within the LOCA environment.
The hcensee responded that certain stem-mounted limit switches on safety-related valves in Unit 2 containment may not be suitable in the LOCA environment.
In addition, one solenoid installed on a safety-related valve in Unit 2 had not been qualified for service in the LOCA environment.
Forty-four limit switches which were equipped with a Conax-type connector were replaced in Unit 2 containment.
The limit switches replaced correspond to'those valves listed in the licensee's response to the bulletin except for valves SI-634 and SI-644. The licensee detennined that the limit switches for these valves need not be replaced because the only function that the stem mounted switches perform is for valve position annunciation which is not considered a safety function.
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The inspector reviewed the following records pertaining to the
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replacement of the limit switches.
a.
Plant Design Change Request; b.
Job Orders; c.
Job Order Check List; d.
Drawings - Red Lined; e.
Installation Procedure; f.
Inspection Plan; g.
Termination Wire List; h.
Acceptance Tests; i.
Receipt and Inspection Records.
A certificate of Compliance from NAMC0 Controls, supplier of the limit switches, states that the limit switches were manu-factured to the same specifications as switch model E 180-11302 which was qualified to IEEE Standards 323 (1974),
344 (1975) and 382 (1972).
NAMC0 Controls was not on the approved buyers list, however, an audit of the supplier was made by Northeast Utilities Service Company on May 10, 1979.
The audit provided evidence that the limit switches provided by NAMC0 Controls were
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-5-adequately represented by those generically similar switches qualification tested on August 31, 1977.
The inspector verified that the Plant Operation and Safety Review Committee had reviewed and approved the Plant Design Change Request. A safety evaluation had been performed in accordance with 10CFR50.59.
The inspector reviewed record., pertaining to the solenoid valve CH517, installed in Unit 2 containment.
This valve is in the Auxiliary Spray charger header. 'Its function is to close at the start of a LOCA and open 12 nours into a LOCA to flush boron from the core.
The solenoid valve was ordered from Plimpton and Hills Cor-poration and supplied by Automatic Switch Company.
Neither campany is on the licensee's approved buyers list.
The licensee plans to conduct an audit in June 1979.
Pending confirmation of the audit with acceptable results, this item is unresolved (50-336/79-17-02).
Records reviewed by the inspector show that ASCO Solenoid Valve, Catalog No. 206-381-6 RVE was listed on'the Purchase Order. The Material Receipt Inspection Report, dated 4/18/79, for the solenoid valve listed the serial number (58842Hl) and not the catalog number.
The Material Inspection Report indicated that a Certificate of Compliance and Pressure and Seat Leakage test results were required.
The report indicated that these two records were received.
However, the Packing Slip dated 4/18/79 from Automatic Switch Company indicated that ASCO solenoid valve Catalog No. 206 381 6 RVF was received.
The Certificate of Compliance dated 4/23/79 listed the valve as catalog No. 206-381-6RF.
The C of C stated that the listed valve met the requirements of IZEE 323 (1974), 382 (1972) and 344 (1975) in accordar.ce with ASCO Qualification Specification AQS-21678, Revision B, 2/15/78.
The licensee stated that the valve installed was a 206-381-6RF. The inspector was not able to enter containment to verify the name plate data on the solenoid valve.
Pending acceptable resolution of the discrepancy in records for the solenoid valve and the verification of the installed valve, this item is unresolved (50-336/79-17-03).
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c.
Safety Relief Valve Electropneumatic System Replacement and Main Piston & Disk Modification in Unit 1 The target Rock Safety Relie.f valves have been modified from a three stage design to a two stage design.
The changes involved:
(1) modifying the main stage to improve venting between main steam ' inlet pressure and the main piston chamber; (2)
replacing the main piston and disc; and (3) substituting the new two stage electropneumatic system for the old three stage electropneumatic system.
The modification was made because pilot leakage in the valve led to inadvertent valve opening and failure to reclose.
In addition, the materials for the electropneumatic system were changed. The initial electropneumatic system body was made from ASTM-A216-Grade WCB as a casting.
The new electropneumatic body is made from ASME-SA-105 as a forging.
In the initial design, the pilot and second stage disc were stellite hard faced.
In the new design, the pilot and stabilizer are both one-piece solid stellite and their seats are stellite hard faced.
A Certificate of Compliance from Target Rock Corporation and a Product Quality Certificailon from the General Electric Company attested to the quality standards and documents that were used in the fabrication, production and testing of the material used in the valves for modification.
The inspector audited some QC records for verifica+!on of quality compliance.
The inspector selected valve S/N 1035 for verification of test data. A hydrostatic test for 10 minute duration was made on the shell and disc of the valve.
Pressure of 2375 PSIG and 3175 PSIG respectively was applied with satisfactory results. Seat leakage test with nitrogen was perfenned in the pilot valve at a pressure of 1040 PSIG for 5 minutes.
Six bubbles per minute were observed which was well within the acceptance criteria. The solenoid and air operator leakage test showed 38323d
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-7-that at a pressure of 120 PSIG there was "0' leakage with the solenoid energized or with the solenoid deem rgized.
The final acceptance test data showed that valve SN/1035 had a nameplate set point of 1095 PSIG and solenoid voltage of 125V DC.
The test results show the following:
Set Ramp Test Point Reseat PSI /
Delay Stroke Response Cycle PSIG PSIG
% Reseat Sec.
MSEC MSEC MSEC
70 185
210
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1104 997 90.3
200
230
1102 983 89.2
200
230
1100 989 89.9
200
230
1101 991 90.4
200
235
1101 992 90.0
200
230
1101 977 88.8
200
230
- 2 N/A N/A N/A N/A 230
260
- 3 N/A N/A N/A N/A 200
230
- 4 N/A N/A N/A N/A 225
255
. *5 N/A N/A N/A N/A 225
255
- Denotes Air Operator Runs The test results show that there was no seat leakage before or after the tests.
The test was conducted at the Target Rock Corporation steam test facility on January 16, 1979.
The test results show that the valve was within the +1%
tolerance range of the setpoint as required by the purchase specification.
Plant Design Change Request (PDCR), Job Orders, Safety Evaluations, and Maintenance Requests were reviewed by the inspector.
There was no record that the Plant Operations Review Comitee (PORC) had reviewed the PDCR as required by facility procedures.
The licensee stated that a review would be done.
This item remains unresolved pending verification that PORC has reviewed the PDCR (50-245/79-13-01)
The licensee submitted a License Amendment Submittal for reload #6 on March 5, 1979.
The submittal did not contain 383235
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-8-a description or request for review of the modification to the Target Rocks Safety / Relief Valves for review and approval by the coninission as required by 10CFR50.59a.
The inspector and the resident inspector for Millstone 1 & 2 discussed this apparent discrepancy with the NRR Project Manager. The inspectors were informad that a generic evaluation had been conducted by NRR and since the modifi-cation resulted in a reliability upgrading of the system, the requirement to obtain prior commission approval to perform the modification could be waived.
No apparent items of noncompliance were identified.
5.
Unresolved Items Unresolved items are matters about which more information is required in order to ascertain whether they are acceptable items, items of noncompliance, or deviations.
Unresolved items disclosed during the inspection are discussed in Paragraph 4 a, b and c.
6.
Exit Interviews The inspector met with licensee representatives (denoted in Paragraph 1) at the conclusion of the inspection on June ',1979.
The inspector summarized the findings of the inspection.
The licensee representatives acknowledged the inspector's findings.
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