ML20205P304

Responds to NRC Re Violations Noted in Insp Rept 50-312/86-07.Corrective Actions:Comprehensive Program to Correct Problems Identified in Control Room/Technical Support Ctr Emergency Filtering Sys Developed

ML20205P304
Person / Time
Site:	Rancho Seco
Issue date:	03/09/1987
From:	Julie Ward SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:	Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
Shared Package
ML20205P264	List: ML20205P260 ML20205P304
References
JEW-87-360, NUDOCS 8704030232
Download: ML20205P304 (6)

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SACRAMENTO MUNICIPAL UTILITY DISTRICT C 6201 S Street. P.O. Box 15830, Sacramento CA 95852-1830.(916)452-3211 AN ELECTRIC SYSTEM SERVING THE F/( F CALIFORNIA Cl 10: y JEW 87-360 Sgg,,,

ER 0 91987 J. B. Martin, Regional Administrator U. S. Nuclear Regulatory Commission Region V, Office of Inspection & Enforcement 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596 Docket No. 50-312 Rancho Seco Nuclear Generating Station License No. DPR-54 RESPONSE TO NOTICE OF VIOLATION 87-01 AS IDENTIFIED IN NRC INSPECTION REPORT NO. 50-312/86-07

Dear Mr. Martin:

By letter dated February 6, 1987, the Sacramento Municipal District was transmitted a Notice of Violation identified in Inspection Report 50-312/86-07. This Notice of Violation concerned excessive air flow within the Control Room / Technical Support Center Emergency Filtering System. In accordance with 10 CFR 2.201, the District provides the enclosed response to the Notice of Violation.

This letter acknowledges the violation cited and describes the District's initended corrective actions for the specific item listed in the Notice of Violation.

Sincerely, 1

Chrf-[ Ward Deputy General Manager, Nucle l Attachment cc: A. D'Angelo J. B. Martin S. Miner Region V (2)

INPO I&E 8704030232 870327 PDR ADOCK 05000312 G PDR If: c/

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ATTACHMENT 1-DISTRICT RESPONSE TO NRC INSPECTION 86-01 ITEM 'C' NOTICE OF VIOLATION-NRC Violation

. Item C. Technical- Specification 3.13.1 requires the Control Room / Technical Support Center (CR/TSC) Emergency Filter System to be operable at all times when containment integrity is required. Technical Specification 4.10 requires a system air flow of 3200 cfm 110%

during periodic testing of the Control Room / Technical Support Center Emergency Filtering System to demonstrate that the system is operable.

Contrary to the above requirements, on October 1, 1985, operating airflow rates through the CR/TSC Emergency Filtration System were measured to range from 3581 to 4170 cfm during the entire duration of the 24-minute surveillance test. Furthermore, during_ actual emergency operation of the B train on December 26, 1985, while containment

, integrity was required, air flow rates ranged from 4071 to 4575 cfm during emergency operation for 8 minutes. No corrective actions were

, taken to correct the excessive air flow rates after the October 1,

1985, surveillance test.

j This is a Severity Level IV Violation.

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District Response to Violation

1) Admission or denial of the alleged violation.

The District acknowledges and admits that a violation occurred with regard to the failure to take corrective actions following indication of high air flow rates for the Control Room / Technical Support (CR/TSC) Emergency filter System HVAC.

2) Reasons for the violation.

In June 1985, the CR/TSC was declared operable after testing by Special Test Procedures (STP) was completed. One of those procedures STP 164, Air Balancing Test Procedure, demonstrated unit air flows within the 3200 cfm i 10% criterion in accordance with Technical Specification 4.10. Section 4.10 of the Technical Specifications was part of Amendment No. 70, which became effective on June 7, 1905. The 3200 cfm criterion was next scheduled for testing in December,1986.

On October 1, 1985, SP 211.01A CR/TSC Emergency Ventilation System Monthly Surveillance Test was perforned. The monthly surveillance is performed for the purpose of showing air flow through the HEPA i

and charcoal filters. System flow rate (cfm) is not part of the acceptance criterion for the monthly surveillance.although the surveillance demonstrates that flow does exist.

During the October 1, 1985, performance of SP 211.01A, the booster fan failed to start and the acceptance criteria were not met.

Because the problem was identified as a controller design problem, the failed surveillance was reported to the NRC as Licensee Event Report (LER) 85-20.

The design problem identified by the October 1,1985, test was corrected by October 3, 1987.

f SP 211.01A was again performed on October 3, 1985. With the t

controller design problem corrected, the acceptance criteria of SP 211.01A were met.

Although the flow rate (cfm) is NOT addressed by the acceptance criterion for SP 211.01A, a copy of the Interim Data Acquisition and Display System (IDADS) computer printout was attached to a copy of the October 3, 1985, performance of SP 211.01A. As cited by the inspector, this IDADS printout indicated flow rates within the Emergency filtration System, between 3581 to 4170 cfm during this performance of SP 211.01A.

The high flow rates were questioned and noted on the IDADS printout by the reviewing engineer, but apparently no further action was taken to investigate the cause of the indicated high flows.

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SP 211.01A was also reviewed by th2 shift sup7rviscr en duty during

. thm pIrfcrmanca cf thz test. As menticned ab:va, however, the flow rates (cfm) are not part'of-the acceptance criteria for SP 211.01A.

f Having fulfilled the acceptance criteria, SP 211.01A was filed along with the IDADS printout'without'further action or investigation. The Emergency filtration System was not declared inoperable.

Although the indicated high flow rates were noted by the review engineer for the October-3, 1987, performance of SP 211.01A, the failure of reviewing personnel and informed supervisors to 4 follow-up with documentation or further action forms the basis of.

this violation.

Since the event on December 26, 1985, (described in LER 85-25),

several reports concerning the function and design of the CR/TSC

essential HVAC have been reported to the NRC. These are

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• LER 86-07 and 86-07, Revision 1, Control Room Emergency HVAC

! High flow Condition LER 86-13, Control Room Emergency HVAC Spurious Actuations LER 86-23, Control Room Essential HVAC System Could Not Perform filtration Safety fcnction during a LOCA and a Low Offsite Grid Voltage Condition.

As indicated by the above listed titles, LER 86-07 and LER 86-07, 1 Revision 1, are related directly to the subject of this violation.

Corrective actions which have been taken, and those which will'be taken as a result of this Notice of Violation and the above listed j LERs, are included in sections 3 and 4 of this response.

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3) Corrective actions which have been taken and results achieved.

At the time SP 211.01A was reviewed, in mid 1985, a single technical support engineer was assigned to review all performed surveillances.

This approach was replaced in July 1986 by the System Engineer Program.

In this program, individual engineers are assigned to-review specific j systems for modifications testing and surveillance.

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In response to the continuing problems with the functioning and design of the CR/TSC Essential HVAC system, a comprehensive program to correct the problems identified with this system has been developed and will be completed prior to plant restart. (Commitment from LER 86-13).

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Within thiscrestart program, the following actions have been completed:-

• A comprehensive System Status Report (SSR) has been developed with the following sections:

1.0 Executive Summary 2.0 System functional Description 3.0 Review of Recommendations and Resolutions 4.0 Test Identification 5.0 Test Results Summary 6.0 Operability findings

• Special Test Procedure STP 198, CR/TSC Essential Air Filtration' Unit flow Test was performed on May 20-23, 1986.

The results of this test indicate that:

1) The measured flow rate through the IDADS system is.

greater than the determined actual system flow rate.

The rates were: '

a) 530 cfm greater for the "A" side filtration System b) 743 cfm greater for the "B" side filtration System

2) The total air flow rates through each CR/TSC Essential Air Filtration unit are within the limitations established by Technical Specifications 4.10.1.B.2.

3) In the current configuration, the HVAC system flow rates stabilize within approximately 15 minutes from the initial start time.

• Calculations have been performed and it was determined that initial system high flow rates (1.0., system start until -

stabilized flow) would not increase above acceptable limits for the calculated dose rates 'for control room operators for the maximum hypothetical radiological accident. These limits are specified in the Updated Safety Analysis (USAR).

• As of June, 1986, the CR/TSC Essential HVAC System has been placed in a " system testing" status. This status is designed to facilitate timely completion of the CR/TSC Essential HVAC system restart program (LER 86-13).

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4) Correctivo steDs Which Will be taken to avoid further-Vinlations:

A surveillance procedure results review guide, AP 303-07, is being

' drafted, (previous ~ commitment number T860428363C).

Departmental training will be provided for personnel who are responsible-for reviewing surveillance procedures prior to restart (previous commitment number T860428366C).

CR/TSC Essential HVAC system startup program will'be completed prior to plant restart. This is a previous commitment resulting from a selected system status report.

IDADS indicated flow rate for each CR/TSC Essential Air filtration Unit will be adjusted prior to restart to be more representative of

.' the actual flow rate. (LER 86-13)

The Essential HVAC System flow controls will be adjusted to reduce

.the time necessary to establish stabilized flow. The time

, necessary to establish stabilized flow will be adjusted prior to i restart so that stabilization occurs at approximately the same time j for both trains (LER 86-13)

A revision to AP.22, Occurrence Description Reports, will be made to ensure that a surveillance failing to meet the acceptance i

criteria will be documented on an AP.22 form. Additionally, a new enclosure will be included with the AP.22 procedure to' require a

! " Justification for Continued Operation" (JCO) whenever the Limiting Condition for Operation LCO "yes" box is marked by the originator of an AP.22. This new enclosure will be completed by the shift j supervisor on duty. (new commitment)

A revision to the Nonconforming Report (NCR) procedure QAP-17 is I

being made in Revision 5 to notify the shift supervisor immediately whenever a nonconformance exists involving installed equipment not removed from service. This revision is currently in the review

! process.

5) Date full compliance will be achieved.

As indicated by the District's response to this Notice of Violation, a i

I significant program has been developed to ensure correction of problems associated with the CR/TSC Essential HVAC system. The program includes 4

testing and return to operational status prior to plant restart. Full compliance will be achieved prior to plant restart.

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