IR 05000313/1989009

Insp Repts 50-313/89-09 & 50-368/89-09 on 890307-10.No Violations or Deviations Noted.Major Areas Inspected:Action on Previous Insp Findings,Dhr Sys Pipe Supports,Hanger Damage & Emergency Diesel Geneator Exhaust Manifold Fires

ML20247Q939
Person / Time
Site:	Arkansas Nuclear
Issue date:	03/30/1989
From:	Clay Johnson, Murphy M, Seidle W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20247Q919	List: IR 05000313/1989009 ML20247Q915
References
50-313-89-09, 50-313-89-9, 50-368-89-09, 50-368-89-9, NUDOCS 8904070224
Download: ML20247Q939 (9)

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APPENDIX U.S. NUCLEAR REGULATORY COMMISSION

' REGION IV NRC Inspection Report: 50-313/89-09 Operating-Licenses: DPR-51 50-368/89-09 NPF-6 Dockets: 50-313 50-368 Licensee: Arkansas Power & Light Company (AP&L)

P.O. Box 551 i; Little Rock, Arkansas 72203 Facility Name: Arkansas Nuclear One (ANO), Units 1 and 2

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l Inspection At: ANO, Russellville, Arkansas

. 1 Inspection Conducted: March 7-10, 1989 )

Inspectors: [ MC M. E. Murphyj, Reactor Inqpector Test Programs 7//o/99 Date Section, Division of Reactor Safety h C. E. Johnson, F) actor Inspector, Plant S-M-3 9 Date-1 I

Systems Sectibh, Division of Reactor Safety )

l Accompanied .

By: D. D. Chamberlain, Chief, Project Section A i Division of Reactor Projects.(March 9-10,1989)  !

J. R. N. Rajan, Office of Nuclear Reactor Regulation, 1 Mechanical Engineering Branch (March 6-8,1989)

J Approved: / 3/Jc / F1-W. C. Seidl(,) Chief Test Programs Section Date i Division of Reactor Safety Inspection Summary Inspection Conducted March 7-10, 1989 (Report 50-313/89-09; 50-368/89-09)

Areas Inspected: Routine, unannounced inspection of licensee action on ,

, previous inspection findings, Unit 1 decay heat removal system pipe supports

! and hanger demage, Unit 2 emergency diesel generator (EDG) exhaust manifold j l fires and containment temperature profiles for both unit "5

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Results: Within the four areas inspected, no violations or deviations were' {

identified It appears that the licensee is addressing the issue of decay heat removal ;

system pipe support and piping damage in an acceptable manner. Although this f issue is not completely resolved, the licensee has narrowed it down to what may l have caused the damage. The licensee expected that a final. resolution would 1 be issued by March 14, 198 ')

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l-3-DETAILS Persons Contacted AP&L l

• J. M. Levine, Executive Director, Nuclear Operations

• E. C. Ewing, General Manager, Plant Support

• C. N. Shively, Plant Engineering Superintendent l

• J. D. Vandergrift, Manager, Operations

• S. McGregor. Engineering Services Superintendent

• W. E. Converse, Operations Assessment Superintendent

• C. Anderson, In-House Event Analysis Superintendent

• B. Eaton, Manager, Design Engineering

• D. Howard, Licensing Manager

• J. L. Taylor-Brown, Superintendent, Quality Control / Engineering i

• D. So, Operations Technician Engineer

• J. McWilliams, Manager, Maintenance B. Michalk, Plant Engineering B. Allen, Plant Engineering G. Higgs, Plant Engineering R. Rispoli, Fire Protection Engineer '

R. Lane, Manager, ANO Engineering

• P. Michalk, Plant Licensing Engineer

• D. Lomax, Plant Licensing Supervisor NRC

• B. Haag, Resident Inspector

• B. Jones, Resident Inspector, River Bend Station

• Denotes those attending the exit intervie . Licensee Action on Previous Inspection Issues (Closed) Deviation (313/8714-02; 368/8714-02): The licensee coni;itted to establishing and maintaining a fire protection program under the guidelines of Appendix A to BTP-APCSB 9.5- Under this program, certain fire barriers were to be tested under the provisions of the plant Technical Specifications (TS). With the advent'of Appendix R, these barriers were no longer being surveillance tested i in accordance with the TS. The licensee has submitted TS change requests to the NRC for both units, which clarify the fire barriers that require surveillance. These barriers include the 10 CFR Part 50.48 (Appendix R) fire barriers, which separate redundant safe shutdown systems, and certain fire barriers separating safety-related i fire areas. These fire areas are the control room, switchgear rooms, battery rooms, diesel generator rooms, and lubricating oil storage

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areas. Pending TS change request approval, the licensee is complyin with present surveillance requirement ')

1 (Closed) Unresolved Item (313/8714-04; 368/8714-04): Some fire barrier. penetration seal designs were not qualified by a standard fire' test. The licensee has submitted the remaining test results to-

. the0fficeofNuclearReactorRegulations.-(NRR)andispresentl resolving and responding to questions from NRR' .

- (Closed) Unresolved Item (313/8714-05; 368/8714-05): The licenseeL could not provide an' analysis.to support the decision to not provide

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ventilation for either Units.1 or 2 electrical equipment /switchgear

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rooms. The NRC inspectors reviewed Calculation No. 87E-0060-02, l dated September 22, 1987, which was completed for the rooms of-concern. This calculation resolves this issu ; Decay Heat Removal System Pipe Support / Hanger Damage- (93702)

Damage was identified to Pipe Support DH-122,. in the decay heat. removal system. Subsequent QC walkdowns, conducted from early February to early March 1989, identified an additional eight pipe supports with varying degrees of damage. The pipe supports, with their respective condition reports (CRs) and a description of the damage, are as follows:

DH-122 CR-89-069 Lugs sheared off piping with 1/2-inch l dent in top of pipe

DH-125 CR-89-078 Bent top guide shoe

DH-163 CR-89-143- Saddle collapsed

.DH-108 CR-89-156 Flat indentations on pipe in the pipe support area-

'DH-93 CR-89-156 Bent' spring. hanger rod (loose grout in nearby wall penetration)

DH-100 CR-89-156 Flat indentations on pipe in the pipe support area

DH-145 CR-89-156 Pipe clamp.is rolled and moved off

- center of, pipe support

DH-273 CR-89-156 Broken grout HS-49 CR-89-157 Snubber clamp has slipped in west direction j

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-5-One additional CR was identified that related to this review since it also described pipe support damage in the decay heet removal system. This CR 1 is88-420, dated November 4, 1988. The damage described was to two Pipe 'i Supports DH-112 and DH-115. Pipe Support DH-112 was found to have a strut deformed and the strut anchor bolts were pulled out of. the floor .

approximately 3/4 inch. Pipe Support DH-115, which is approximately 30 feet downstream of Pipe Support DH-112. was found pulled away from the wall approximately 1/4 inch. Both of these pipe supports are on the borated water storage tank (BWST). supply line to the "B" decay _ heat removal system. The licensee's position on the damage to these pipe I supports is that it may have occurred when the system was refilled from the BWST to return it to service.. Normal refill should be. performed by manually opening the BWST isolation valve. This evolution was accomplished by opening the isolation valve from the control room, which

, resulted in rapid valve opening. The piping configuration allowed a

! column of water to fall-in the system piping approximately 30 feet. This resulted in a "waterhammer" effect in the system, which may have caused the hanger damage, Observations of Damaged Pipe Supports The NRC inspectors, accompanied by licensee representatives,' walked down portions of the decay heat removal system to observe several damaged pipe supports identified in the CRs. Five pipe supports were observed by the NRC inspectors. Observations of the pipe supports revealed the following:

Pipe

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Support N Observations

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DH-100 Flat indention on south side of pipe. Not very noticeable. It appears to have been caused by thermal growth or excessive force against

. suppor DH-108 Dent located at bottom of pipe. Shape'of dent does not match ~or conform to shape of suppor It appears that this dent may have been caused previously from a deleted support.

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DH-93 Springhangersupport(rod) bent. Grout dislodged I

and. cracked at penetration where pipe enters the wall. There appears to have been upward movement of the piping system that could have caused the bent hanger roc' and the dislodging of grout at penetratio DH-112- This pipe support was repaired. The licensee has a-viable cause for the damage to this support and DH-115. Observation of an adjacent support by

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-6-i rubbing marks indicated that there was 2 to .)

3 inches of movement in the axial direction. - 4 DH-122 Observation of this support indicated a large dent ,

at the top,of the. pipe and.a smaller dent at the q bottom of the pipe. .Two stainless steel (SS) lugs i sheared off on.the east side (top and bottom)'. 'No H obvious damage to the. pipe walls. It appears tha ..

some type.of transient occurred, which caused.the !

pipe'to move up and down with a twisting motio The twisting motion was. concluded because of.the scrape, marks _left by the'SS. lug Observation of the above pipe supports indicated that piping at Support DH-122 was damaged the mos b. Issues Discussed in Conference Meetings-The NRC inspectors.had several meetings with licensee personnel to discuss actions the licensee had taken to determine the root cause of damage to the supports. Also, the actions now in progress.or planned

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to be done were discussed. The specific actions discussed asi listed

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below:

(1) Actions Completed by the Licensee QC inspectors walked-down the A&B decay heat removal system to document anything out of.,the ordinary in.the way of damaged supports and pipin Engineering reevaluated the loads #on the damaged pipe 1 support Engineers walked down the decay heat removal system to j detect any damage pipe or bowing of pip *

A pump test was performed.on Decay Heat ~ Removal Pump P34A.= !

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A consultant performed a. preliminary evaluatio .

(2) Actions to be Taken by Licensee Prior to Heat-Up '

Assess all support deficiencies against the Support DH-122 ,

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Establish the CR-1-89-0069 Root Cause' Action ~ Plan:

Determine the applicability of NUREG 522 Determine the amount of nondestructive testing require o .

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-7-Determine the severity of the even ~

Quantify the mechanical damage and determine if components are to be replace *

Incorporate the Plant Engineering Action Pla Decide how to address the other support-related CR Conduct a design evaluation of classical load cases and thermal stratificatio Generate a document that. consolidates the AN0'and Little Rock-Generating Office Engineering position with respect to system

. qualification, root cause, and consequences of a future even l l Review system operation history with respect to loop utilization, number of operations, and problems.

1 Conference Call on Issues to be Addressed Prior to Heat-Up A conference call was held on March 14, 1989, with representatives from Region IV, NRR, and ANO. This conference call was held to discuss issues that must be addressed prior to heat-up. This included the decay heat removal system. The licensee confirmed the action already completed and its continued effort on determining the root cause. From this conference call, it appears that the licensee has narrowed the root cause to two scenarios. The'11censee is still in the process of evaluating the damaged supports and deformed piping. No concrete resolution has-been given for the repair or fix of the supports or piping; however, it does appear.that the licensee is aggressively addressing this issue for adequate resolutio In conclusion, it appears that the licensee is_ addressing this _ problem in j an adequate manner. Resolution on some items still remain and will be resolved prior to restar . Unit 2 Emergency Diesel Generator (EDG) Exhaust Fires (93702)

The NRC inspectors reviewed the licensee's root cause determination for Unit 2 EDG exhaust fires. This determination covered CRs 88-0151, 88-0207, and 89-0050. These CRs document fires during performance of

,onthly surveillance tests. The fires were located in the vicinity of the flanged transition pieces between the exhaust manifold header and the i turbocharger. The fires and smoke were due to the combustion of lube oil i which leaks out of this flange connectio The source of lube oil in the exhaust manifold header is -leakage past the upper piston rings during draindown immediately following diesel generator engine operation. Some contribution to the quantity may also occur during

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-8-extended prelubrication just prior to a diesel engine run. The lack of'an effective joint seal at the flange connection provides the leakage path'

out of the header from pressurization following-a. diesel start. . As the exhaust line heats up, the flange reseals and stops the oil source._ The licensee has been in contact with the vendor, Fairbanks-Morse, and other4 utilities using' the same equipment. This. condition is not unique to AN There has been a history of the same, and related, exhaust header fire problems.

l Subsequent to the completion of.the inspection, it was. learned that'the licensee has on site a replacement transition piece that fits-between the l . exhaust manifold header and turbocharger. The licensee intends to ll install this piece'in the near ter The vendor is presently working on a long-term fix for the flange lea An interim method of operation is being developed by the' licensee, with the vendor's concurrence, which is intended to reduce the quantity of' oil leakage into the header, presently, tiie occurrence of open flames has been eliminated on the diesel engines except for one flange joint on the .

"B" ED There were no violations or deviations identified in this' area of the inspectio . High Temperature Inside Containment (TI 2515/98)

The purpose of this inspection was to obtain containment average ambient'

operating temperature profiles for ANO Unit 1 and 2 to determine its'

effect on the environment qualification.of equipment, in particular,.

electrical insulation. The information and drawings gathered will be sent to NRR for further review, including the questionnair Complete history of ANO, Unit 1, is explained in detai1 in the Justification

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forContinuedOperations'(JCO),datedAugust 27, 1987. TI 2515/98 was initiated because of ANO, Unit 1, high temperatures. Unit I has committed to maximum temperatures stated in the JC Review by the NRC. inspectors

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of the temperature recordings'for June, July, and August 1988, indicated ~ that the temperatures were within acceptable. limits as_ committed _to by the JC Review of the temperature recordings for Unit 2 for June 1988, also indicated that the average temperature recordings were within-the limit as required by TS 3.6. In conclusion, it appears Unit 1 has had improvement-in the detection of high temperatures with the addition of temperature elements located conservatively inside containment. It also appears that Unit 2

. containment temperature is . held within the TS limit a

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] Exit Interview ,

l The NRC ins ectors met with the licensee personnel (denoted in paragraph 1 on March 10, 1989, and sumarized the' scope and findings of -

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this inspection.- No 'information was identified as proprietar :,

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