ML20094N173

From kanterella
Jump to navigation Jump to search
Responds to NRC Re Violations Noted in Insp Repts 50-445/95-17 & 50-446/95-17 on 950730-0909.Corrective Actions:Design Mod to Raise Elevation of Openings of SFP Ventilation Ducts Was Expedited & Completed
ML20094N173
Person / Time
Site: Comanche Peak  Luminant icon.png
Issue date: 11/03/1995
From: Terry C
TEXAS UTILITIES CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20094N163 List:
References
NUDOCS 9511270402
Download: ML20094N173 (5)


Text

-

1 M

==

Log # TXX-95272 L

File # 10130 IR 95-17 C

C Ref. # 10CFR2.201 1UELECTRIC i

i c tm=Twry November 3. 1995 ca evw m I

U S. Nuclear Regulatory Commission Attn:

Document Control Desk Washington. D.C.

20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)

DOCKET NOS. 50-445 AND 50-446 NRC INSPECTION REPORT NOS. 50-445/95-17: 50-446/95-17 RESPONSE TO NOTICE OF VIOLATION Gentlemen:

TU Electric nas reviewed the NRC letter dated October 5.1995, concerning the inspection conducted by Resident Inspectors Messrs. A.T. Gody. Jr..

H.F. Freeman. and Ms. V.L. Ordaz during the period of July 30 through September 9. 1995.

The Inspection Report and attached Notice of Violation were dated October 5. 1995.

The Notice of Violation describes a failure to follow operating procedures which resulted in lowering the Refueling Water Storage Tank level below the minimum Tecr.nical Specification level for operability.

Our response is attached.

9511270402 951120 PDR ADOCK 05000445

$f-O/7f G

PDR P.O. Box 1002 Glen Rose. Texas 76043

1 l

)

TXX-95272

.l Page.2 of 2

)

i a

Please do not hesitate to contact ~Neil Harris at (817) 897-5449 to coordinate any additional information you may need to facilitate closure of this issue.

.]

-1 i

i Sincerely, j

1 C. L._ Terry By:

Mhh M.

R'. Blevins Plant Manager-NSH:nsh Attachment t

cc:

Mr. L. J. Callan. Region IV Mr, W. D.' Johnson. Region IV Resident-Inspectors i

,- to TXX-95272 Page 1 of 3 RESTATEMENT OF THE NOTICE OF VIOLATION (50 445/95-17: 50 446/95 17)

During an NRC inspection conducted on July 30 through September 9. 1995.

one violation of NRC requirements was identified.

In accordance with the

" General Statement of Policy and Procedure for NRC Enforcement Actions,"

(60 FR 34381: June 30. 1995), the violation is listed below:

Technical Specification 6.8.1 requires that written procedures be established implemented, and maintained covering the applicable procedures recommended in Appendix A of Regulatory Guide 1.33 Revision 2. February 1978.

i Regulatory Guide 1.33. Appendix A, recommends written administrative procedures for operation of the Emergency Core Cooling and Fuel Storage Pool Purification and Cooling Systems.

Comanche Peak Steam Electric Station System Operating Procedure (SOP)-506,

" Spent Fuel Pool Cooling and Cleanup System," was written to govern the operation of the refueling water purification system and requires in Step 5.12.1.0 that Valve "XSF-0025. SFP DEMIN X-02 SFP RET VLV LVG-11, is closed" when performing that portion of the procedure.

Contrary to the above, while aligning the refueling water purification system to the refueling water storage tank (RWST) on August 3, 1995, licensee operators cross-connected the RWST to the spent fuel pool when they opened Valve.XSF-0025. rather than ensuring Valve XSF-0025 was closed as was required by operating Procedure 50P-506, Step 5.12.1.U.

This caused the RWST level to decrease below the 95 percent minimum level, as required by Technical Specifications 3.5.4 and 3.1.2.6.

REPLY TO NOTICE OF VIOLATION (50 445/95 17; 50 446/95 17)

TV Electric accepts the violation.

The requested information concerning the violation is provided as follows.

1.

Reason for the Violation On August 3. 1995 while operating the refueling water purification system to purify the Unit 1 Refueling Water Storage Tank (RWST), an j

improper valve lineup resulted in overflowing the Spent Fuel Pool (SFP) X-01 into the fuel pool surface ventilation ducts and decreasing the RWST level below the minimum value allowed by Technical Specifications due to personnel reading operating procedure step (s) incorrectly.

Several alarm windows are available to operators to provide warning

'in the event of the RWST draining down.

Also, the RWST level is

i to TXX-95272 Page 2 of 3 monitored by the Plant Computer.

The plant computer points for RWST low level and the annunciator windows were set below the limiting Condition for Operations level.

The annunciator point for the Spent Fuel Pool high level alarm, was above the bottom of the fuel pool surface ventilation ducts.

These setpoint problems caused the annunciators and plant computer not to alarm prior to RWST low level being reached and allowed water to enter the SFP surface ventilation ducts without warning the operators, f

TU Electric has subsequently reviewed the event and concluded that personnel error was the root cause of the event. ~ Causal factors included; personnel involved in the evolution were not at the_ pre-job briefing, water level trending / monitoring for the Refueling Water Storage Tank or Spent Fuel Pool was not performed, self-verification -

a for procedure use was less-than-adequate and no annunciation was received throughout the event.

i 2.

Corrective Steos Taken and Results Achieved In response to the decreasing water level in the RWST and water entering the SFP ventilation ducts, the following actions were taken:

1.

RWST level decrease was stopped by securing the refueling. water purification pump and securing the associated valve lineup, J

2.

RWST level was restored, and 3.

The Radiation Protection (RP) organization restricted Fuel Building access to minimize the potential of spreading contamination during spill containment and cleanup.

1 The initial actions mitigated the loss of water from the RWST and the SFP anc restored the RWST level to Technical Specification-requirements.

RP activities assured contamination control during spill cleanup.

3.

Corrective Steos Taken to Avoid Further Violation The condition where water could potentially enter the SFP ventilation-i ducts prior to the high level setpoint for the SFP being reached was previously identified in an engineering calculation in December 1992.

As the result of this event, the existing design modification to raise the elevation of the openings of tne SFP ventilation ducts was expedited and completed. This modification has corrected the physical problem of the duct openings being lower than the SFP high level alarm.

The setpoints for the plant computer for RWST Low-Level alarm, was changed to assure operator notification prior to entering a Limiting Condition of Operations.

The applicable operating procedure for the Spent Fuel Pool Cooling and Cleanup System was revised to include independent verification for single barrier valves.

Several other Operations procedures were modified to assure guidance for water transfer and RWST level alarm

to TXX-95272 Page 3 of 3 updates. The Shift Managers conducted meetings with members of~their crews to discuss performance items that led to the event and to clarify / reinforce expectations.

Operations issued a Lessons Learned on the event which includes Management's expectations concerning.

monitoring evolutions, self-verification and maintaining questioning attitudes.

I A temporary local measuring device has been installed in the SFPs to -

permit local determination of level changes which will be monitored twice per shift when there are no evolutions in progress, and once per hour when activities are being performed which could cause pool

(

level changes.

A video camera has been placed in the Fuel Building and connected to a video terminal in the Control Room to allow for remote monitoring of the X-01 Spent Fuel Pool level until permanent local SFP level measuring device (s)'have been installed.

These permanent modifications' are in progress at this time.

4.

Date of Full Comoliance TV Electric is in full compliance at this time.

f

-