ML20210U021

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Insp Repts 50-259/86-27,50-260/86-27 & 50-296/86-27 on 860728-0801.Violation Noted:Improper Torquing of Bolts on Diesel Generator Cooling Water Check Valves
ML20210U021
Person / Time
Site: Browns Ferry  Tennessee Valley Authority icon.png
Issue date: 09/09/1986
From: Blake J, Girard E
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20210T992 List:
References
50-259-86-27, 50-260-86-27, 50-296-86-27, NUDOCS 8610090368
Download: ML20210U021 (10)


See also: IR 05000259/1986027

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UNITED STATES

-[ A utoq'o NUCLEAR REGULATORY COMMISSION

[

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n REGION 18

101 MARIETTA STREET,N.W.

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  • t- ATLANTA, GEORGI A 30323

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Report Nos.: 50-259, 50-260, and 50-296/86-27

Licensee: Tennessee Valley Authority

6N 38 A Lookout Place

1101 Market Street

Chattanooga, TN 37402-2801

Docket Nos.: 50-259, 50-260 and 50-296 License Nos.: DPR-33, DPR-52,

and DPR-68

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. Facility Name: Browns Ferry 1, 2, and 3

Inspection Conducted: July 28 - August 1, 1986

Inspector: [ 8[cFI

E. 'rard D' ate' Signed

Approved by: 9 6b

J. . Jila ce, Section Chief D&te Signed

En inyering Branch

D viyion of Reactor Safety

SUMMARY

Scope: This routine, announced inspection was conducted in the areas of welding

project program, Nuclear Manager's Review Group (NMRG) review of corrective and.

preventive maintenance, main steam isolation valve leakage reduction modifica-

tions, and licensee action on previous enfor:.ement matters and followup items.

I Results: One violation was identified - Torquing of bolting on diesel generator

cooling water check valves, paragraph 3.f.

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8610090368 860929

PDR ADOCK 05000259

G PDR

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REPORT DETAILS

1. Persons Contacted

Licensee Employees

  • J. Swindell, Unit 3 Superintendent

T. Cosby, Unit 2 Superintendent

  • R. Shulz, V, Manager, Compliance Engineering
  • J. Savage, Compliance Engineer

Diesel Generators

G. Harland, Maintenance Planning Supervisor

  • R. Worthy, Mechanical Test Section Supervisor

K. Mullins, Mechanical Engineer, Mechanical Test Section

  • H. Hodges, Mechanical Engineer, Mechanical Test Section

J. Nebrig, Mechanical Engineer, Maintenance

D. Trousdale, Maintenance Engineer

R. Guthrie Division of Nuclear Engineering, Browns Ferry

J. Pleva, Engineer, Employee Concerns Program

NRC Resident Inspectors

  • G. Paulk, Senior Resident Inspector

C. Brooks, Resident Inspector

  • Attended exit interview

2. Exit Interview

The inspection scope and findings were summarized on August 1,1986, with

those persons indicated in paragraph 1 above. The inspector described the

areas inspected and discussed in detail the inspection findings listed

below. No dissenting comments were received from the licensee.

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Violation 259, 260, 296/86-27-01, Torquing of bolting on diesel genera-

tor cooling water check valves, paragraph 3.f

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Inspector Followup Item 259, 260, 296/86-27-02, Does common start date

l for ISI program apply to pump and valve testing, paragraph 8.f

l The licensee did not identify as proprietary any of the materials provided

l to or reviewed by the inspector during this inspection.

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3. Licensee Action on Previous Enforcement Matters

a. (0 pen) Violation (259, 260, 296/84-40-01): Improper Acceptance Crite-

ria for Pressure Isolation Valves

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This violation described deficiencies in TVA's acceptance criteria for

pressure isolation valve (PIV) leakage. The leakage acceptance limit i

specified for each PIV was the lower of either the maximum relief valve

capacity in the adjoining low pressure piping or the maximum leakage ,

that would allow 10 CFR 50, Appendix J, Type C test acceptance require- l

ments to be met. The NRC concern was that such limits could be so high  ;

that PIVs whose leakage values indicated severe degradation and immi- 1

nent loss of safety function would not receive necessary corrective l

action. For example, permitting valve leakage to approach the capacity

of relief valves might negate the protection from overpressurization l

the relief valves had been intended to provide. For the PIVs whose  !

recorded leakages were examined when the violation was identified, it l

appeared that PIV leakages 100 times normal values could be considered '

acceptable on the basis of the licensee's criteria. j

TVA's corrective action in response to this violation, identified in

their January 21, 1985 letter, was to change their acceptance limits to

50% of those previously used. Region II did not accept this response

but indicated that its acceptability would be the subject of discussion

with the NRC Office of Nuclear Reactor Regulation (NRR). It was

intended that this matter would be resolved with NRR during the comple-

tion of the NRC evaluation of the TVA pump and valve test program.

During the current inspection, the NRC inspector discussed this matter

further with TVA and verified that they had performed the corrective

action stated in their letter. In addition, the inspector informed TVA

that, as there had been extended delays in completion of the evaluation

of their pump and valve test program, NRC will address the

matter of PIV leakage acceptance requirements.

b. (0 pen) Unresolved Item (259, 260, 296/84-40-02): Leakage Test Accep-

tance Requirements for CIVs

This item addresses an NRC inspector's concern that TVA does not fully

comply with ASME Section XI requirements for testing of containment l

isolation valves (CIVs). As with Violation 259, 260, 296/84-40-01 in

a. above, Region II intends that this matter will be resolved during 1

the NRC evaluation of the TVA pump and valve test program. Because of

the continued delays in completion of that evaluation, Region Il now i

intends to request that the ASME Section XI requirements for CIV

testing be addressed as a separate issue. )

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c. (0 pen) Unresolved Item (259, 260, 296/85-07-01): Adequacy of Actions

taken with Regard to Allegations Concerning Category 1 Supports.

This item expressed concern that the licensee failed to sufficiently

investigate the alleged violation of procedures by a general foreman

and a project engineer.

During inspection 85-07, the plant manager committed to a further

investigation. In the current inspection, the inspector inquired as to

the status of the commitment and was informed that the investigation

had been delayed but that it was now in progress. The inspector

discussed the item with the engineer from the TVA Employee Concerns

Program who had been assigned to the matter. The engineer asked the

inspector if he could provide any details from his knowledge or from

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NRC files that might aid in his investigation. The inspector referred

the engineer to information described in Inspection Report 85-07 and to

a TVA internal memo referenced in report 85-07. The inspector informed

the engineer that, based on discussions with the Region II Enforcement

and Investigation Coordination Staff, he could provide no information

from their Region II files at this time.

This item will remain open pending completion of the associated TVA

investigation and a review of that investigation by Region II.

d. (Closed) Violation (259,260,296/85-18-01): Procedures for Inspection

of Diesel Generator Cooling Water Valves.

TVA's letter of response, dated September 4,1985, has been reviewed

and determined to be acceptable by Region II. The inspector held

discussions with licensee's representatives and examined the corrective

actions as stated in the letter of response. The inspector concluded

that TVA had determined the full extent of the subject violation,

performed the necessary survey and followup actions to correct the

present conditions and developed the necessary corrective actions to

preclude recurrence of similar circumstances. The corrective actions

identified in the . letter of response have been implemented.

e. (Closed) Violation (259, 260, 296/85-18-02): Portion of Emergency

Equipment Cooling Water System Not Classified as Critical Systems,

Structures and Components (CSSC).

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TVA's letter of response, dated September 4,1985, has been reviewed

and determined to be acceptable by Region II. The inspector held

discussions with licensee's representatives and examined the corrective

actions as stated in the letter of response. The inspector concluded

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that TVA had determined the full extent of the subject violation,

performed the necessary survey'and followup actions to correct the

present conditions and developed the necessary corrective actions to

preclude recurrence of similar circumstances. The corrective actions

identified in the letter of response have been implemanted.

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f. (Closed) - Violation (259, 260, 296/85-18-04): Records for Valve

. Inspections.

TVA's letter of response, dated September 4,1985, has been reviewed

and determined to be acceptable by Region II. The inspector held

discussions with the licensee's representatives and examined the

corrective actions as stated in the letter of response. The inspector.

concluded that TVA had determined the full extent of the subject

violation, performed the necessary survey and followup actions to

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, correct the present conditions and developed the necessary corrective

actions to preclude recurrence of similar circumstances. The corrective

l actions identified in the letter of response have been implemented.

In verifying TVA's corrective actions, the NRC inspector reviewed

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records for the (preventive maintenance) inspections that TVA performed

on the diesel generator (DG) cooling water check valves in late 1985

and early 1986. These valves are understood by the inspector to be of

essentially identical design and make. The inspections were performed
by maintenance craftsmen and documented on TVA Maintenance Request

Forms (MRs) 583701 thru 6, 574683 and 574687. Included with the

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completed MRs as records of the work were torquing data sheets. The

i inspector found that the records of the inspections appeared satisfac-

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torily recorded and retrievable with no repetition of the conditions

identified in. Violation 259, 260, 296/85-18-04. However, the inspector

observed that the torquing records indicated inadequate performance of

i the torquing of the pressure boundary bolting on the safety-related DG ,

cooling water check valves, as evidenced by the following:

! (1) TVA Standard Practice BF-3.2 requires the torquing of pressure

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retaining bolting on safety-related valves to be a QC inspection

l nold point. The torquing of the pressure retaining valve bolting

prescribed by MRs 583701 thru 583706, 574683, and 574687 did not

include QC inspection hold points and the MRs indicate that no

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QC inspection of the torquing was performed.

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i (2) The subject MRs specified that valve bolt torquing was to be

! performed in accordance with Mechanical Maintenance -Instruction

(MMI) 143 which requires that the size and type of bolt be

determined and recorded, and that the information be used to select

torque values from the tables in MMI 143. All of the bolting

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materials were 5/8 inch studs with no type or grade identification

and on that basis MMI 143 would require a torque value of 93 ft-lbs

for all of the valve bolts. In conflict with the MMI 143 procedural

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requirements:

f (a) Bolt size and grade were incorrectly determined and recorded on

[ the following MRs:

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1 MR 583704 (grade recorded as B7)

-2 MR 583701 (size recorded as 3/4 inch and grade as " alloy

steel")

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(b) For the size and grade of bolting (b/8 inch size and

indeterminate grade) MMI 143 specifies a torque of 93 ft-lbs.

Instead, the following torque values were recorded on MMI 143

data sheets, as used:

1 200 ft-lbs for MR 583701

2 100 ft-lbs for MR 583706

3_ 90 ft-lbs for the remaining MRs

NOTE: In response to the NRC inspector's questions the cognizant

TVA engineer telephonically contacted the valve manufacturer who

responded informally with a recommended torque value of 60

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ft.-lbs.

The inspector found that torquing procedure MMI-143 was relatively

complex and difficult to use. The inspector was informed that it

had been deleted and superseded by one or more other procedures

early in 1986. The inadequacies in the torquing and torquing

procedure described above are considered a nonconformance with

Technical Specification requirements for compliance with procedures

for preventive maintenance and was identified to the licensee as

Violation 259, 260, 296/86-27-01, Torquing of Bolting on Diesel

Generator Cooling Water Check Valves.

4. Unresolved Items

Unresolved items were not identified during the inspection.

5. Welding Project Program

In response to allegations and concerns expressed with regard their welding,

TVA formed a Welding Project to determine the adequacy of their welding

program and weldments. The work of Welding Project was described as being

conducted in two phases:

l Phase I

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[ Ensure that the written TVA welding program correctly reflects regulatory

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requirements and commitments and identify and categorize concerns /

j deficiencies in the program.

Phase II

Evaluate the implementation of the program; verify that weldments in the

field meet requirements and are adequate for service; correct any problems,

j and implement changes to prevent recurrence.

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The NRC inspector questioned cognizant TVA Welding Project personnel as to

the status of the program they had undertaken at Browns Ferry. The inspector

was informed that the Phase I work had been completed and a report of the

results would be submitted to the NRC in September 1986. They stated that

the field inspections for Phase II would be completed about August 7,1986,

and that their evaluations and submittal of a final report would be complet-

ed about the end of 1986.

The inspector was informed that the field welds selected for inspection had-

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been chosen to minimize accessibility and ALARA concerns. It was not clear

to the inspector that this would result in adequate sampling of the field

welds.

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6. Nuclear Manager's Review Group (NMRG) Review of Corrective and Preventive

Maintenance

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The inspector questioned the licensee as to the status and findings of the

review of corrective and preventive maintenance that had been recently

performed. The Unit 2 superintendent, who had been involved in the review,

informed the inspector that the review was complete and a report would be

issued the week of August 4,1986. He stated that a copy of the report

would be provided to the NRC.

7. Main Steam Isolation Valve (MSIV) Leakage Reduction Modifications

The licensee's MSIVs had been found to experience serious degradation of
leak tightness between outages, resulting in leakages above desired accep-

l tance levels. As a consequence, various modifications were made to the

! valves in order to reduce the degradation. The inspector questioned licen-

l see personnel as to the effectiveness of the modifications. Data shown to

the inspector indicated that the leakage rate increase between outages had

been reduced by about a factor of 100, but that it still exceeded the

acceptance limit by a factor of about 5.

8. Inspector Followup Items (IFIs)

i a. (0 pen) IFI (259, 260, 296/84-40-03): Justification for Pump Test

l Allowable Ranges

This item was opened by the inspector to identify, for followup review,

i the allowable ranges of pump test parameters specified by the TVA's

surveillance test procedures. The code that governs the licensee's

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pump testing, ASME Section XI, provides a tabulation of allowable

ranges for pump inservice test parameters. The related text in the

code, subsection IWP-3210, states that if the tabulated ranges cannot ,

be met for a pump, the owner shall specify reduced range limits to

i allow the purp to fulfill its function. TVA (the owner) uses limits

-that are less restrictive than those tabulated in the code for some of

their pumps and it was TVA's justification for use of these modified

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limits that was of interest to the inspector in this item. The inspec-

tor discussed the matter with the responsible TVA engineer, and asked

if the need for the increased ranges could not be justified through a

simple statistical analysis of the variability in past pump test

results. The engineer agreed to collect the historical data and

demonstrate the acceptability of their test limits. This item will

remain open pending review of the data justifying the limits,

b. (Closed) IFI (259, 260, 296/84-40-04): Training and Qualification

Requirements

This item expressed the inspector's interest in the TVA training and

qualification requirements applied to the engineers who analyze pump

and valve test results and the personnel who determine the acceptabili-

ty of CIV leakage rates. The required training was discussed with the

engineering personnel responsible for analyzing pump and valve test

results and with the onsite personnel responsible for CIV leakage

tests. On the basis of information provided in these discussions the

inspector determined that this item may be closed. The training and

qualifications will be examined further as part of the routine inspec-

tion program.

c. (0 pen) IFI (259, 260, 296/84-40-05): Interpretation of RG 1.26

This item identified the NRC inspector's intention to request that TVA

be provided an NRC clarification of Regulatory Guide (RG) 1.26. The

inspector believes that the licensee has misinterpreted RG 1.26 and, as

a consequence, may have improperly classified certain pumps and valves

utilizing classification guidance in RG 1.26. The inspector had

expected that NRC guidance on use of RG 1.26 would be provided to TVA

during completion of the NRC evaluation of their pump and valve test

program. However, because of delays in the NRC evaluation, this has

not been accomplished. TVA was informed that Region II will request

the clarification separate from the NRC evaluation of the pump and

valve test program. This item will remain open pending TVA

receipt of the clarification.

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l d. (Closed) IFI (259, 260, 296/84-40-06): Excessive Reliance on One

Individual for Valve Maintenance

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This item expressed an inspector's concern that TVA relied excessively

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on one engineer for maintenance on safety-related valves. Responsible

TVA maintenance personnel informed the inspector that this was no

longer true, that there were now several qualified individuals perform-

ing the work. Based on his discussions with those individuals the

inspector determined that this item would be closed.

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e. (0 pen) IFI (259, 260, 296/84-40-07): Historical Information on

Equipment

This item identified an inspector's concern that the licensee's mainte-

nance history records might not be complete and that they had not

provided a satisfactory response to related concerns expressed in NRC

Generic Letter (GL) 83-28 Item 2.2. The inspector discussed this

matter with responsible TVA personnel, including the Maintenance

Planning Supervisor. Based on his discussions, the inspector deter-

mined that TVA had made significant improvements in this area. Howev-

er, based on an April 23, 1985 letter from the NRC, TVA had still not

provided a satisfactory response to GL-83-28, Item 2.2. The inspector

indicated that this item would remain open pending NRC's acceptance of

the subject GL response and pending a Region II review of examples of

their equipment history records.

f. (0 pen) IFI (259, 260, 296/84-40-08): Exercising Testables Check Valves

This item was opened by the inspector to identify a concern that TVA

provide assurance that their testable check valves were adequately

tested in accordance with the applicable code, ASME Section XI. The

inspector informed TVA of the NRC position on acceptable testing of

check valves when the item was opened.

In the current inspection, the NRC inspector questioned responsible TVA

personnel regarding their action on this matter. The inspector was

informed that the testing to be performed on these valves will be

described in a revised program for inservice testing of pumps and

valves that TVA now has in preparation.

This item will remain open pending Region II's review and of the

testing description.

In relation to the inservice testing program, the inspector questioned

whether the program was to cover the common ASME Section XI program

interval for all three units that had been approved by the NRC in a

letter to TVA, dated June 20, 1986. The responsible TVA engineers

informed the inspector that they had interpreted the interval approved

in the June 20 letter to apply to nondestructive examinations and

hydrostatic testing but not to pump and valve testing. The inspector

indicated he would obtain NRC clarification and identified the matter

as Inspector Followup Item 259, 260, 296/86-27-02, Does Common Start

Date for ISI Program Apply to Pump and Valve Testing.

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g. (0 pen) IFI (259,260,296/85-07-02): Adequacy of Procedures

This item identified an inspector's intention to assure that -TVA

procedures MAI-23, BF 8.3, and other procedures used for piping support

inspections be reviewed for adequacy. Such procedures have been

reviewed further by an NRC inspector as described in NRC Reports 85-26

and 86-19. Additional information pertaining to the adequacy of the

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procedures may be developed through the reinspections being performed

by the TVA Welding Project (see paragraph 5 above) and this item will

remain open pending NRC review of the Welding Project report.

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