RBG-30250, Revises Response to Violations Noted in Insp Rept 50-458/88-08.Corrective actions:100% Review of 31 High Temp Leak Detection Alarms Performed & Errors Identified & Corrected

Revises Response to Violations Noted in Insp Rept 50-458/88-08.Corrective actions:100% Review of 31 High Temp Leak Detection Alarms Performed & Errors Identified & Corrected

ML20236D680
Person / Time
Site:	River Bend
Issue date:	03/06/1989
From:	Deddens J GULF STATES UTILITIES CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
RBG-30250, NUDOCS 8903230216
Download: ML20236D680 (5)

Text

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,k- ,O GULF STATES UTILITIES COMPANY .

emn em stanos ecsr ornce em m sr nw.asmuaoV651ANA 70776 AREA C006 504 635-8094 346 8651 March 6,1989 RBG- 30250 File Nos G9.5, G15.4.1 U. S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555 Gentlemen:

River Bend Station - Unit 1-  %

Refer to: Region IV  %,.  ;

Docket No. 50-458/ Report 88-08 This- letter revises Gulf ' States Utilities Company's '(GSU) response to the Notice of Violation contained in NRC ; Inspection Report No. 50-458/88-08. The inspection was performed by Messrs.  !

Chamberlain and Jones during the period of February 16. - March l 31, 1988 of activities authorized by Operating License NPF-47 for River Bend Station - Unit 1.

GSU's revised response to Notice of- Violation 8808-01,

" Inadequate Alarm Response Procedure", is provided in the.

enclosed attachment pursuant to 10CFR2.201. Changes to the original response are noted with sidebars in the right margin.

This completes GSU's response to this item.

Sincerel ,

J. C. Deddens Senior Vice President' g River Bend Nuclear Group JCD/. / / K/ ch cc: .U. S. Nuclear Regulatory Commission.-

Region IV 611 Ryan' Plaza Drive, Suite 1000 l Arlington, TX 76011 NRC Senior Resident. Inspector -

P. 0. Box 1051 St. Francisville, LA 70775 k'3[

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- 8903230216 890306 PDR ADOCK 05000456

-Q- PDC _ _ _ _ _ _ _ _ _ __ ___ ]

i UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION ,

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STATE OF LOUISIANA )T ]

i PARISH OF WEST FELICIANA )

Docket No. 50-458 In the Matter of )

GULF STATES UTILITIES COMPANY ) l (River Bend Station - Unit 1) i AFFIDAVIT J. C. Deddens, being duly sworn, states that he is a j Senior Vice President'of Gulf States Utilities Company; that k l

he is authorized on the part of said company to sign and file  ;

with the Nuclear Regulatory Commission the documents attached hereto; and that all such documents are true and correct to

! the best of his knowledge, information and belief.

l l

J. C./D6ddens l

Subscribed and sworn to before me, a Notary Public in and for the State and Parish above named, this [f Ik-- day of 7Y) (AA/) / , 19 $ 7 . My. Commission expires with Life.

)(iuf1L v. / 6(d>

Claudia F. Hurst Notary Public in and for West Feliciana Parish, Louisiana l

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ATTACl9 TENT Response to Notice of Violation 50-458/8808-01

REFERENCE:

NoticeofViolation-LetterfromL.J.ChlantoJ.C.Deddens,datedMay2, 1988.

INADEQUATE ALARM RESPONSE PROCEDURE: _

River Bend Station Technical Specifications, paragraph 6.8.1.a, requires that procedures for activities identified in Appendix A of Regulatory Guide 1.33, Revision 2, February 1987 be established, implemented and maintained.

Paragraph 5 to Regulatory Guide 1.33 requires that alarm annunciator procedures "contain: (1) the meaning of the annunciator, (2) the source of the signal, (3) the immediate action that is to occur automatically, (4) the immediate operator action and (5) the long-range actions."

Cont- 'y to the above, it was discovered on March 10, 1988, that the source of the signals defined in alarm response procedure ARP-601-19, "P601-19 Alarm Responses," Revision 2, were incorrect in that the alarm.setpoints were incorrectly stated for alarm numbers 2403 and 2409. These alarms are for main steam tunnel ambient temperature high and main steam tunnel ventilation differential temperature high. In addition, the immediate and long range actions were inadequate in that actions for alarm 2403 defined the temperature at which the main steam tunnel temperature should be maintained below 180 degrees F rather than the correct value of 130 degraes F. If cooling systems cannot prevent the temperature from approaching the main steam valve isolation setpoints, no additional operator actions were specified to prevent a full main steam line isolation at high reactor power levels.

REASON FOR VIOLATION:

, The alarms in question are initiated by non-safety related recorders, and I thus are not classified as safety related. However, the alarms are designed to alert the operator to high temperature conditions in an area protected by high temperature isolation logic, and are generational aids for that reason.  :

Setpoints are included in the River Bend Station (RBS) alarm response procedures (ARPs) in excess of RG 1.33, " Quality Assurance Program Requirements (Operations)", guidelines as a supplementary source of information for the operator. Thus, the errors cited in the potential violation are considered to have no safety significance as related to the procedure.

Review of the procedural error, undertaken as immediate corrective action and as discussed with the NRC Senior Resident Inspector, revealed that in the past the ARP was correct- but the setpoint information was changed to incorrect values during one of the revision cycles. Both of the alarms had been actuated for an extended period due to unreasonably low setpoint selection. At the time the ARP errors were discovered, modification request (MRs)85-1154and86-1035 were in process 'of being worked to raise the Page 1 of 3 c

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q setpoints of the alarms in question to values within two degrees of the erroneous values. Corrective action for the . specific errors has been I completed and TCNs were issued correcting the inaccurate ARPs. ]

The roo't cause of the error is determined to be lack of understanding of the system alarm design details during procedure development. As designed, each leak detection thermowell contains two thermocouple, each identified with the same mark number. One thermocouple provided input to the Riley temperature switch, which in turn supplies a trip signal at the isolation  ;

setpoint to the trip logic, the isolation alarm, and the meter module. The j other thermocouple inputs to- the temperature recorder, which actuates the i pre-isolation alarm at a lower setpoint. The ARPs in question listed as the 1 initiating device both the temperature switch and the temperature recorder i that are fed by the thermocouple with identical mark numbers. The isolation setpoint, rather than the correct pre-isolation setpoint, was listed in the j ARP. 1 Contributing factors to the lack of understanding of the system design details during procedure development is the method of identifying two thermocouple with the identical mark number.

1 CORRECTIVE STEPS WHICH HAVE BEEN TAKEN AND RESULTS ACHIEVED:

l A 100% review of thirty-one high temperature leak detection alarms was performed. Errors similar to those cited were identified and ccrrected. J Thirteen ARPs contained errors based on the same confusion between the 1 temperature switch / temperature recorder as the alarm initiating device. .For pre-isolation alarms, when the temperature switch was erroneously included'as an initiating device, the temperature switch's setpoint was invariably listed J as the alarm setpoint. In some of the thirteen ARPs, pre-isolation alarms  !

erroneously included the automatic, operator, and long term actions i appropriate to the isolation alarms. In addition, two ARPs were found to j l contain random setpoint errors. Corrective action for.the above deficiencies j l is complete, and consisted of portions of TCNs 88-0296, 88-0298, 88-0303, and )

88-0304.

Nine additional alarm deficiencies were detected during the corrective action review that are attributed to design documentation errors. Four alarm windows, for Divisions 1, 2, 3, and 4 turbine shield wall high temperature, had been installed without the installation of the alarms themselves.

Corrective action to remove the four alarm windows is work complete via MR 88-0136.

l Five alarms contained incorrect wording.

Three of the five describe the isolation as originating in a specific division, rather~than the correct origination in either division. The remaining two incorrectly list the area experiencing the high temperature. Corrective action for the five alarm wording deficiencies is included as a portion of MR 88-0146.

The ARP deficiencies, and the design documentation errors described above, are considered to have no safety significance. Automatic plant responses would have occurred as required. Furthermore, the. availability of actual ,

. area' temperature data, and other diverse indications of plant system operations continued to provide the operator with a comprehensive plant status.

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_ - _ _ _ _ __ ___- _ _____-_ _ _- - a

Information for both elements of each dual element thermocouple originally discovered has been combined into a single loop calibration report (LCR).

The instrument loop for each thermocouple was originally addressed by three different LLRs. The consolidation into a single LCR provides clear identification of the mark e bers, setpoints and trip functions of each bi-stable device using the thermoc3uples as sensors. When operating or maintenance personnel use the LCR, they will have all of this information summarized in one convenient document. Furthermore, the LCRs are used extensively as reference documents in the preparation of Alarm Response Procedures (ARPs). This consolidation of LCRs will help minimize the possibility of confusion during the preparation of ARPs. It will be obvious in the LCR which alarm is energized by a particular bi-stable device.

CORRECTIVE STEPS WHICH WILL BE TAKEN TO AVOID FURTHER VIOLATIONS:

Corrective action to prevent reoccurrence will consist of training and required reading for all licensed personnel. The training will consist of a review of leak detection system design drawings and loop calibration reports.

The required reading will consist of the TCNs that corrected the ARP errors.

This corrective action will be complete in September 1988. The two ARPs with random setpoint errors are considered to be isolated human errors, thus no specific corrective action to prevent reoccurrence is addressed.

Additional corrective action shall consist of a 100% review of ARPs for main control room alarms. The review will be performed in accordance with plant procedure OSP-005, " Operations' Procedure Review and Revision", and will include verification of alarm name, initiating device, setpoint, automatic actions, operator actions, long term actions, possible causes, and references. This review will be complete in March 1989.

Each of the other ARPs containing errors based on the same confusion between the temperature switch / temperature recorder as the alarm initiating device will have its associated LCRs incorporated into a single LCR by September 1, 1989.

DATE WHEN FULL COMPLIANCE WILL BE ACHIEVED:

Corrective action will be completed by September 1, 1989. l Page 3 of 3