ML20235W109

Forwards Proprietary Wyle Labs Test Rept 17040-1 Re Bunker Ramo Instrument Penetration Assemblies (50027267, 781113-1-04/50027267-06,780911-1-01),per 881102 Meeting.Rept Withheld (Ref 10CFR2.790)

ML20235W109
Person / Time
Site:	Byron, Braidwood, 05000000
Issue date:	02/24/1989
From:	Hunsader S COMMONWEALTH EDISON CO.
To:	Murley T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
Shared Package
ML19302D645	List: ML20235W109
References
0021V, 21V, NUDOCS 8903100497
Download: ML20235W109 (3)

Text

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- Ccmm:nwraith Edison

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%s One First National Plaza, Chicago, Illinois

• AdJress Reply to: Post Office Box 767 Chicago, Illinois 60690 - 0767 February 24, 1989 i

Dr. Thomas E. Murley, Director Office of Nuclear Reactor Regulation

U.S. Nuclear Regulatory Commission Washington, DC 20555 Attn

Document Control Desk

Subject:

Byron Station Unit 2 Braidwood Station Unit 2 Bunker Ramo Instrumentation Penetration Module E.O. Testing NRC Docket No. 50-455 and 50-457 References (a) Facility Operation License, NPF-77 dated May 20, 1988 (b) NUREG-1002, Safety Evaluation Report, Supplement No. 6, dated June, 1988 (c) November 9, 1988 S.C. Hunsader letter to T.E. Murley (d) December 19, 1988 S.C. Hunsader letter to T.E. Murley (e) November 14, 1988 S.C. Hunsader letter to T.E. Murley (f) January 13, 1989 S.C. Hunsader letter to T.E. Murley (g) January 31, 1989 G. Holahan letter to Cordell Reed Dear Dr. Murleys On November 2, 1988, a meeting was held between Commonwealth Edison (Edison) and the NRC Staff to discuss the environmental qualification (EQ) test plan for the Bunker Ramo Instrumentation Penetration modules installed in Braidwood Unit 2. This EQ test was planned to establish the environmental qualification of these components to meet the requirements defined in License Condition 2.D of reference (a), as evaluated by the NRC Staff in reference (b).

During the meeting, the general discussion included a review of the schedule to be followed to complete the EQ testing. As a result, for the use of the NRC Staff, reference (c) provided a more detailed schedule defining key testing milestones. Subsequently, reference (d) provided the NRC Staff with an update on the EQ testing and the Unit 2 outage schedules. Consistent with the testing schedule that was presented, the LOCA test was started on January 4, 1989 and was completed on January 27, 1989.

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Reference (d) indicated that the results for the first 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> of the LOCA test would be made available to the NRC Staff for review. Those results were provided in reference (f). (The 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> testing time represents a time equivalent to 140 days into the LOCA). The purpose of this letter is  ;

to provide the final test report which is included in Attachment "A" that satisfies the requirements in License Condition 2.D. for Braidwood Unit 2.

The information in the final report includes the same information provided in reference (f), plus additional insulation resistance (IR) readings taken daily, throughout the remainder of the test.

As presented in Attachment "A", satisfactory IR values (greater than 1 x 106 ohms) were measured. At the peak LOCA condition, six (6) IR readings were taken on circuit I-7. Three (3) readings were taken at 50 VDC and three (3) readings were taken at 500 VDC. For the 50 VDC condition (representative of an instrumentation circuit) the conductor to conductor IR reading was 4.0 X 10 7 ohms, and the two (2) conductor to ground IR readings were 3.5 X 107 ohms and 1.3 X 109 ohms, respectively. For the 500 VDC condition the conductor to conductor IR reading was 9.5 X 10 8 ohms, and the two (2) conductor to ground IR readings were 1.1 X 10 9 and less than 1.0 X 105 ohms, respectively. The one lower than expected IR reading is attributable to the measuring technique used that caused a reverse flow of current through the megohmmeter as the DC circuit discharged. If a circuit discharges through the megohmeter, the current will drive the megohmeter down-scale, resulting in an inadequate reading. In this one case the meghometer pegged low at its lowest scale point of 1 X 10 5 ohms. Subsequent IR readings taken during the test on this circuit have been satisfactory.

Based on the above, this one inconsistent IR reading is not believed to be attributable to any failure of the module, and no other inconsistencies were seen throughout the remainder of the test. During the remainder of the test all IR measurements were greater than 4.2 x 106 ohms with many in the 1.0 x 107 ohms to 1.0 to 109 ohms range.

Leakage currents were continuously monitored throughout the test on a number of other circuits. Reviews of the test data indicate no detectable leakage during the first 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> of the LOCA test as well as throughout the remainder of the testing. These results demonstrate that the Bunker Ramo instrument penetration modules are environmentally qualified for their intended function, including the worst case LOCA condition, and supports Edison's original position in that regard.

Reference (e) had informed the NRC Staff that Edison's current outage i

planning would establish a start date of the Braidwood Unit 2 surveillance outage as late as February 11, 1989. This outage started on February ll, 1989. Edison requests that the NRC Staff review of the information provided in this submittal be performed in a manner to be completed prior to start-up following completion of this outage. Start-up is scheduled for March 25, 1989. Timely review by the NRC staff will support the actions being taken to satisfy License Condition 2.D of reference (a).

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. Reference (g) provided the NRC staff's findings and request for additional information regarding the resolution of these issues involving the environmental qualification of the.same penetration modules installed at Byron Unit 2. Specifically, the NRC staff stated, that the test report previously

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submitted in August, 1988, "...did not provide sufficient IR readings to demonstrate functional operability during LOCA simulation". The' staff indicated that "... the necessary action to establish qualification is to l conduct an EQ test as required by 10 CFR 50.49." The NRC staff requested that-

! Edison furnish no later than 90 days from the date of reference (g), Edi s o r.< ' s ,

l "... plans and schedule to either qualify, test or replace the subject l penetrations with ones which have been previously demonstrated to be qualified l per the licensing criteria applicable to.the facility."

l In response to reference (g), the test report provided in Attachment A to this letter addresses this request and the concerns made by the NRC staff. Since the design and installation at Byron Unit 2 is the same as i

Braidwood Unit 2, the test results given, equally apply to the Byron and Braidwood Stations.- As a result, the Wyle final test report demonstrates and establishes that the Bunker Ramo instrument penetration modules are environmentally qualified for their intended function, including the worst case LOCA condition et Byron Unit 2 as well. As such, there is no need and Edison has no plans to replace these penetration modules at Byron Unit 2.

The information contained in Attachment A is considered to be proprietors by Edison. As such, Edison requests that this information be controlled in accordance with 10 CFR 2.790. Please address any questions concerning this matter to this office. Edison is available to meet with the NRC staff to support the NRC review n ocess, as deemed necessary.

Very truly yours,

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S. C. Hunsader Nuclear Licensing Administrator I

/sc1:0021V 1-3 Att.'s: (A) Wyle Test Report 17040-1 dated 2-24-89 cc L. Olshan-NRR S. Sands-NRR J. Hinds-RIII R. Gardner-RIII Resident Inspector-Braidwood Resident Inspector-Byron

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