IR 05000373/1986034

Safety Insp Repts 50-373/86-34 & 50-374/86-35 on 860731 & 0812.No Violation or Deviation Noted.Major Areas Inspected: Potential Environ Qualification Concerns Re 10CFR50.49 Designated Raychem Heat Shrink Tubing & Taped Splices

ML20212N387
Person / Time
Site:	LaSalle
Issue date:	08/25/1986
From:	Gautam A, Muffett J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20212N365	List: IR 05000373/1986034 ML20212N362
References
50-373-86-34, 50-374-86-35, IEIN-86-053, IEIN-86-53, NUDOCS 8608280207
Download: ML20212N387 (6)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION III

Reports No. 50-373/86034(DRS); No. 50-374/86035(DRS)

Docket Nos. 50-373; 50-374 Licenses' No. NPF-11; CPPR-100 Licensee: Commonwealth Edison Company '

P.O. Box 767 Chicago, IL 60690 Facility Name: LaSalle County Station, Units 1 and 2 Inspection At: Commonwealth Edison and S&L Offices, Chicago, IL, July 31, 1986, and at Glen Ellyn, IL on August 12, 198 Inspection Conducted: July 31 and August 12, 1986 Inspector:

A. S. Gautam f % g 9- 9 % 25g/e6 Date Yb (W '

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02 Sb Approved By: J. W. Muffett, Chief /

Plant Systems Section Date Inspection Summary Inspectica on July 31 and August 12, 1986 (Reports No.50-373/86034(DRS);

50-374/86035(ORS))

Areas Inspected: Announced special safety inspection by regional inspector of potential environmental qualification (EQ) concerns regarding 10 CFR 50.49 designated Raychem Heat Shrink Tubing and Okonite Taped electrical splice Results: No violations or deviations were identified, however, an ongoing NRC review is being performed to evaluate discrepancies found in the Raychem and Okonite splices in Units 1 and \

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I DETAILS 1. Persons Contacted Commonwealth Edison Company (Ceco)

1. • H. Massin, LaSalle Project Engineer, SNED

• S. Dileto, LaSalle Project Engineer, SNED

1. • D. Spencer, LaSalle Technical Staff Engineer Sargent & Lundy (S&L)

R. Mazza, Project Director

• M. Zar, Electrical Engineer

• R. Pollock, LaSalle Project Engineer

• J. Sinnapan, Supervisor, CQD

• B. Pickiney, Engineer CQD

• J. Esternan, Electrical Engineer

• Denotes those present during the interim exit meeting at the Sargent &

Lundy, Chicago office on July 31, 198 # Denotes those present during the exit meeting on August 12, 1986.

2. Review of 10 CFR 50.49 Designated Electrical Splice Concerns:

On June 26, 1986, the NRC issued IE Information Notice No. 86-53,

" Improper Installation of Heat Shrinkable Tubing," to alert licensees to a potentially generic safety problem involving improper installation of heat shrinkable tubing over electrical splices and termination On June 20, 1986, with Unit 2 in cold shutdown at the LaSalle County Station, the licensee determined that electrical Raychem spliced terminations at the inboard and outboard Main Steam Isolation Valve limit switches and outboard feedwater check valve limit switches and solenoids were not installed per EQ tested configurations. The licensee issued LER 86-012 on July 15, 1986, and reported the cause of the above discrepancy to be EQ instructions not being incorporated into required installation procedures. The licensee later identified similar discrepancies with Okonite taped splice Since LaSalle Unit 2 was tentatively scheduled to start up August 4, 1986, a special NRC safety inspection was conducted on July 31, 1986, at the CECO and S&L downtown Chicago offices to review justifications for the operability of EQ equipment associated with these splice Primary areas reviewed included evaluation and testing conducted by the licensee to justify operability, the impact of discrepant splices on the safe operation and shutdown of the plant; and corrective action planned by the licensee prior to start up. The following conclusions were drawn:

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a. Evaluatica and Testing of Raychem and Okonite splices Based on their onsite inspection at LaSalle Unit 2 the licensee identified the following discrepancies:

(1) Deficient overlap lengths of Raychem tubing WCSF-N on appropriate EQ splices. For example, Raychem Heat Shrink tubing did not overlap a minimum of 2" on both sides of-the splice as established by environmental qualification testin (2) Lack of use of Raychem shims required to build up the conductor insulation up to the useable range of Raychem heat shrink tubing. For example, conductors having thin KAPTON insulation had been spliced to field cables having much larger diameter insulation without the use of shims to build up the thin KAPTO (3) Deficient ' overlap lengths of Okonite T-95 insulating tape and No. 35 jacketing tape. For example, in some cases terminations did not have Okonite tape in the crotch reg;un of two wires spliced in a "V" formation, and in some cases there was zero overlap with cable insulatio (4) Okonite wires taped over cloth braid jackets on ASCO solenoid conductors (pigtails). The licensee stated that this deficiency applied only to ASCO installations and that all such EQ

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installations will be repaired prior ,to startu None of the other discrepancies referenced in IE Notice No. 86-53 were identified by the licensee to be present at the LaSalle County Stations. The inspector reviewed the licensee's evaluation of the environmental qualification of WCSF-N inline Raychem splices in CQD File No. CQD-031204, Revision 0, dated July 30, 1986, and engineering evaluation of Okonite splicing tapes T-95 and No. 35 CQD, in CQD File No. CQD-031187, Revision 0, dated July 30, 1986, for evidence of qualification of as installed and as modified Raychem and Okonits splices. These documents identified field inspections and evaluated results of qualification testing of Raychem and Okonite. In order to perform this evaluation of 10 CFR 50.49 environmentally qualified Raycherr. and Okonite splices, the licensee contracted S&L engineers to review EQ binders for equipment requiring such qualified interface A field inspection was then conducted by the licensee in response to IE Notice 86-53 for as installed WCSF-N Inline Raychem splices at LaSalle County, Units 1 and 2, and discrepancies noted. It was during this review that licensee inspectors also questioned Okonite T-95 and No. 35 insulating and jacketing taped splices. This discrep acy was identified and controlled in a timely manne l

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The licensee took a conservative approach to correcting the above discrepancies by immediately starting repairs in the plant and also contracting Wyle Laboratories to test the "as installed" configurations, as well as more severely deficient specimens for performance during

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a design basis accident. This timely initiative by LaSalle County Station made it the first plant in the country to provide some conclusive test data to help mitigate generic industry concerns regarding deficient splice Repair of certain deficient splices was accomplished by applying appropriate layers of Okonite tape ever deficient Raychem splice The licensee reported that thie, approach was implemented on containment electrical penetrations made by Amphenol Samms, and on control cables at the Hydrogen Recombiner. Other splices were repaired by replacement of splicing material with a qualified Raychem configuration. The licensee stated that such repairs were done on ASCO solenoid valves and on devices utilizing KAPTON insulated c9nductors spliced without shims. The licensee confirmed the above activities in their August 7,198C letter to Mr. James Keppler, RIII, and in their letter stated that all remaining questionable applications of Raychem and Okonite had been identified and found acceptable based on correct installation, or based on subsequent qualification testin Qualification testing of various Raychem and Okonite field installed configurations as well as more deficient configurations were performed at the Wyle Laboratories, Huntsville, Alabam The NRC inspector reviewed the Wyle Lab Qualification Plan 17829-01 dated July 10, 1985, for the testing of Raychem and Otanite tapes and determined that the qualification standards, specifications, test standards, specifications, test specimens, test sequence, and acceptance criteria were appropriate for the environmental gaalification of the installed Raychem and Okonite splices during a Design Basis Accident. The inspector also reviewed Wyle Laboratories Letter Test Report Summary 17852-1 dated July 23, 1986, for Raychem splices; and Wyle Laboratories Letter Test Report Summary 17856-1 dated July 29, 1986, for Okonite Tapes; and based on information reviewed determined that all specimens met the acceptance criteria of the Qualification Plan 17829-01. In both tests W'le y Labs stated that the voltage did not drop to less than 10% of the CECO nominal voltage (108 VAC and 432 VAC) for 120 VAC and 480 VAC circuits respectively. The lowest IR measurements during the test were reported by the licensee to be greater than 107 ohms. Thermal aging and LOCA profiles with addition of margins were in accordance with plant requirements. Test anomalies were reviewed by the inspector and found acceptable. Wyle test results documented in the licensee's evaluation indicated the following: 1

(a) Raychem WCSF-N sleeves with overlaps as small as 1/8" over

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cable insulation are qualified for use at LaSalle Units 1 and (b) Okonite tapes T-95 and No. 35 are adequate for repair of

. improperly installed Raychen sleeves; compatible with Raychem sleeve WCSF-N material; and qualified for use at LaSalle Units 1 and l

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'(c) Okonite inline splices and "V" splices are environmentally qualified as installed at LaSalle Units 1 and 2:

The qualification tests discussed above qualify the discrepant splices for eight years. The licensee is committed to either performing further tests within six months or repairing these splices so as to qualify them for 40 years. Final test reports with complete data have not yet been received and filed in the appropriate EQ binders, but are expected to be done prior to startup of Unit 2. Based on the above information, the inspector determined the Wyle tests to be acceptabl Impact of Deficient _ Spli_ces_on_ Plant __ Safe _ty During this review both LaSalle County Unit I was in a refueling outage and Unit 2 was in a shutdown due to investigation of Static-0-Ring pressure switch failures. Unit 2 is scheduled to start up tentatively by August 8, 1986. The NRC was concerned that during a Design Basis Accident, spray due to high energy line breaks and containment spray in the containment could cause failures in instrument and control circuits due to leakage currents between inadequate splices and enclosures. The licensee reported that no 10 CFR 50.49 designated instrunentation is installed inside the LaSalle primary containment and that all EQ penetration splices had been repaired. In addition to this, as a BWR, LaSalle does not take credit for containment spray (RHR cooling mode) during an accident and may not initiate spray until six to eight hours after the initiation of the Design Basis Accident. As discussed in Section 2a of this report the licensee has performed extensive qualification testing and evaluated their

"as installed" Raychem and Okonite splices to be environmentally qualified. Based on the above review the NRC inspector had no imediate concerns regarding the startup of Unit 2. The licensee is committed to qualifying or replacing all deficient Raychem and Okonite splices in both units prior to startup. An ongoing review shall be performed by the NRC to review final test data relative to the qualification of discrepant splices for a qualified life of 40 year During this review the NRC inspector determined that Unit 2 was operating past the November 30, 1985, EQ deadline without qualification documentation on file for the installed configurations of the Raychem and Okonite splices. The inspector also concluded that adequate Raychem and Okonite instructions were available for proper installation of these splices; apparently these instructions were not followed (LER 86-012). At the conclusion of this inspection the licensee was informed that in accordance with guidance in Generic Letter 85-15,

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enforcement action will be considered, in that the licensee should have known these splices were unqualified prior to the November 30, 1985, EQ deadline. Pending further review this is an unresolved item (373/86034-01(DRS); 374/86035-01(DRS)).

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.... Corrective Action During this review and by their August 7,1986, letter to Region III, the licensee connitted to replacing or qualifying through testing and analysis all unqualified Raychem and Okonite splices prior to the startup of LaSalle County Station Units 1 and 2. The licensee has examined each kind of EQ equipment on their master list under Work Request L-59133 and reported that they have repaired or qualified splices in Unit 2 as necessary. Equipment having terminations on

' terminal blocks, connectors and other mechanisms not requiring a secondary insulation system were not examined. The licensee reported that considerable effort and money was being spent for an even more detailed review of splices in Unit 2, and that all records of inspections in both units along with QC reviews were available.onsit The NRC plans to perform a walkdown of splices as well as review records of inspection during an upcoming regional EQ audit at the LaSalle Station. Pending further review of corrective action, this is an Open Item (373/86034-02(DRS); 374/86035-02(DRS)).

3. Open Items Open items are matters which have been discussed with the licensee, which will be reviewed further by the inspector, and which involves some action on the part of the NRC or licensee or both. An open item discicsed during this inspection is discussed in Paragraph 2 . Unresolved Items An unresolved item is a matter about which more information is required in order to ascertain whether it is an acceptable item, an open item, a deviation, or a violation. An unresolved item disclosed during this inspection is discussed in Paragraph 2 . Exit Interview The Region III inspector met with the licensee representatives (denoted under Paragraph 2) at the conclusion of the inspection on August 12, 1986. The inspector sunnarized the purpose and findings of the inspectio The licensee acknowledged this information. The inspector also discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspectio The licensee did not identify any such document!./ processes as proprietary, s

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