ML18153C123

Responds to NRC 900123 Ltr Re Violations Noted in Insp Repts 50-280/89-32 & 50-281/89-32.Corrective Actions:Use of Lab Hood Attached to F-2 Fan Suction Prohibited & Contaminated & Radioactive Items Removed from Hood

ML18153C123
Person / Time
Site:	Surry
Issue date:	02/22/1990
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
90-036, 90-36, NUDOCS 9003060100
Download: ML18153C123 (6)

Text

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VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 February 22, 1990 United States Nuclear Regulatory Commission Serial No.: 90-036 Attention: Document Control Desk SPS/CMM/pmk R2 Washington, D.C. 20555 Docket Nos.: 50-280 50-281 License Nos.: DPR-32 DPR-37 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 REPLY TO A NOTICE OF VIOLATION NRC INSPECTION REPORT NOS. 50-280/89-32 AND 50-281/89-32 We have reviewed your letter dated January 23, 1990, in reference to the NRC inspection which was reported in Inspection Report Nos. 50-280/89-32 and 50-281/89-

32. Our response to the violation described in the Notice of Violation is provided in the attachment.

We have no objection to this inspection report being made a matter of public disclosure.

If you have any further questions, please contact us.

Very truly yours, V)L~

W. L. Stewart Senior Vice President - Nuclear Attachment cc: U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, N. W.

Suite 2900 Atlanta, Georgia 30323 Mr. W. E. Holland

• NRC Senior Resident Inspector Surry Power Station

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Attachment Response to Notice of Violation Reported During the NRC Inspection From October 16-20 and October 30-November 3, 1989 Inspection Report Nos. 50-280/89/32 and 50-281 /89-32 NRC Comment:

During the Nuclear Regulatory Commission (NRC) inspection conducted on October 16-20, 1989 and October 30 - November 3, 1989, a violation of NRC requirements was identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," 10 CFR Part 2, Appendix C (1989), the violation is listed below:

1o CFR 50.59(a)(1) states that the holder of a license authorizing operation of a production or utilization facility may make changes in the facility as described in the Safety Analysis Report, without prior Commission approval unless the proposed change involves a change in the Technical Specifications incorporated in the license or an unreviewed safety question.

Section 9.13.4 of the Surry Updated Final Safety Analysis Report (UFSAR),

Design Evaluation, states that the ventilation systems in areas of potential contamination provide contamination control by ensuring that air is not recirculated, that 10 or more air changes per hour are supplied, and that air is supplied to the least likely areas to be contaminated for circulation to and exhaust from locations subject to the greatest contamination potential.

Section 11.3.3.3 of the UFSAR, Ventilation Vent Particulate and gas Monitors, states that a multi-probe isokinetic sampler is provided to obtain a representative sample in the 80 inch diameter duct.

10 CFR 20.201 (b) requires that each licensee make or cause to be made such surveys as may be necessary to comply with the regulations in 10 CFR 20 and surveys are reasonable under the circumstances to evaluate the extent of radiation hazards that may be present.

Technical Specification 4.9.E requires that the dose rate due to lodine-131, Tritium, and all radionuclides in.particulate form with half life greater than eight days in gaseous effluents shall be determined to be within the limits of Technical Specification 3.11.B.1 (Offsite Dose Limitations) in accordance with the Offsite Dose Calculation Manual by obtaining representative samples and performing analyses in accordance with the sampling and analysis program specified in Table 4.9.2 This table specifies authorized gaseous effluent release types and sample frequency .

• Contrary to the above, the licensee's evaluation of the modification to the ventilation system did not adequately address the resulting effects on the system air flow in that the resulting modifications did not ensure that air was supplied to the least likely areas to be contaminated for circulation to and

exhaust from locations subject to the greatest contamination potential as stated in Section 9.13.4 of the Updated Final Safety Analysis Report (UFSAR).

Additional radiation monitors were added to the Ventilation-vent No. 2 sampling system without an adequate safety evaluation in that the effect of the additional flows required for these monitors were not properly evaluated for its effect on sample representativeness.

Flows of air from degraded and leaking ventilation systems to the environment potentially containing radioactive materials were not sampled to determine compliance with 10 CFR 20 and, Section 3.11.B.1, 3.11.B.2 and 3.11.B.3 of the Technical Specifications (TSs).

Samples of effluent from Ventilation vent No. 2 were not in accordance with Section 4.9.E of the TSs which require representative samples to be obtained from gaseous effluents.

This is a Severity Level IV violation (Supplement IV) .

Response to Notice of Violation Inspection Report Nos. 50-280/89-32 and 50-281/89-32

RESPONSE

(1) ADMISSION OR DENIAL OF THE ALLEGED VIOLATION The violation is correct as stated.

(2) REASON FOR VIOLATION A proper evaluation of changes to the ventilation system operational configuration was not performed. The operation of the system in this configuration is the reason for the portions of the violation concerning ventilation flow contrary to the UFSAR and leakage from portions of the service building ventilation system ductwork.

Prior to modifications to the counting room and chemistry lab areas, service building ventilation system flow was changed from the normal operating system alignment through Ventilation Vent Stack #1 (VENTVENT #1) to the alternate system alignment through VENTVENT #2. This change was necessary to ensure effluent releases from the station ventilation systems were monitored. A design change to rebuild the counting room and chemistry lab was developed considering service building ventilation system discharge through VENTVENT

1. 1. Alignment of the service building system through VENTVENT #2, which discharges to the higher pressure auxiliary building system, increased the backpressure in the discharge ducting of the F-2 and F-12A&B fans. The extended operation subject to this backpressure resulted in degradation of the service building duct joints and leakage into Mechanical Equipment Room (MER) #2. This leakage was not monitored prior to October, 1989. Failure of the duct backdraft dampers resulted in backflow out of the laboratory hoods.

The portions of the violation concerning non-representativeness of samples are attributed to the addition of radiation monitors to the VENTVENT #2 sampling system without performing a thorough evaluation of system impact. Each of the monitors added to the sample line included an appropriate isokinetic sample nozzle. However, the sample line flow rate during simultaneous monitor operation was not consistent with the associated design flow for the vent stack.

(3) CORRECTIVE STEPS WHICH HAVE BEEN TAKEN AND THE RESULTS ACHIEVED Corrective steps taken to resolve concerns on the ventilation system flow include prohibiting the use of the laboratory hood attached to the F-2 fan suction and removal of contaminated and radioactive items from the hood. The hood has been posted "DO NOT USE" and the F-2 fan has been tagged out of service. Fan F-12A is being run continuously to exhaust the three hoods remaining in service. To ensure that the F-12A fan remains in service, the fan has been tagged informing operations personnel not to make changes to the ventilation system alignment or operation without prior concurrence from Health

Physics. Each of the in-service hoods has an outside air curtain which blows down the face of the hood. Based on anemometer readings, the hoods are inflowing with velocities from 100 to 175 fpm. With this configuration, the primary system pressurized sample venting has not caused radiation spiking in the Primary Decontamination Area (PDA) as had been previously experienced.

The requirements of UFSAR Section 9.13.4 are being met.

Immediate corrective repairs of the service building ventilation system duct were completed on October 24, 1989. Air samples taken in the vicinity of the leaking duct verified that the effluent leaving VENTVENT #2 is representative of the leakage into MER #2. The amount of leakage into MER #2 prior to duct repairs, was determined to be less than two percent of the normal 140,000 cfm flow of VENTVENT #2. This leakage was evaluated and determined to be within acceptable limits provided that the concentration of radioisotopes remains less than one MPC. Following the immediate corrective repairs, leakage from the ductwork was estimated to be 200 cfm or less.

An independent walkdown of the service building ventilation system was conducted and an evaluation of the design was performed. The final report was issued January 15, 1990. This report recommends restoring the radiation monitor to VENTVENT #1 and returning the fan flows from F-2 and F-12 to VENTVENT #1. Satisfactory operation of the service building contaminated exhaust streams will resume upon completion of these changes.

To resolve the concerns of non-isokinetic sampling of the VENTVENT #2 effluent, the flow control valve for the Victoreen monitors has been moved downstream of the backup Accident Range Gas Monitor to prevent dilution of the backup Accident Range Gas Monitor. This relocation resulted in a lowering of the flow rate through the VENTVENT #2 isokinetic nozzle to approximately 1O cfm during normal operation. The Kaman Monitor, which is the primary post-accident noble gas monitor, is still drawing approximately 0.5 to 1.0 cfm above isokinetic flows during routine operation. However, this monitor is not typically used for radioactive effluent accountability during normal operation. In addition, procedure revisions to change the sample flow rate for the Victoreen monitor as a function of ventilation system flow rates have been completed. This action will provide representative samples to the monitors for future effluent accountability.

(4) CORRECTIVE STEPS WHICH WILL BE TAKEN TO AVOID FURTHER VIOLATIONS Additional corrective actions are required to return the ventilation systems to the normal design configuration. Periodic walkdowns of the temporary repairs are being performed until permanent repairs are completed. Additionally, station drawings depicting the ventilation system will be revised to reflect the current operational alignment of the ventilation systems to discharge through VENTVENT #2. The leaking backdraft damper on the F-2 fan discharge will be repaired. The recommendations of the independent evaluation have been

• reviewed and a design change is being developed to return VENTVENT #1 to operation including installation of a new radiation monitor. Permanent repairs to the square duct, fans, and dampers will follow the separation of the service building and auxiliary building ventilation systems.

To avoid further violations due to non-representativeness of effluent samples, sample flow requirements are being reviewed for the VENTVENT #2 effluent monitor to ensure a representative sample. The scope of the review encompasses an evaluation of the system design, a walkdown of the sampling system, a review of applicable operating procedures and determination of the steps necessary to maintain isokinetic flow rates. In addition, the control program for the Kaman monitors will be enhanced to provide better control of the sample flow rates for the monitor.

The items identified in this violation occurred prior to enhancements to the design control program committed to the NRC in the Surry Power Station Reply To Notice Of Violation dated July 14, 1989 (Serial No. 89-390A). These enhancements have been implemented to ensure that the cumulative effects of plant modifications are properly considered in the design process for future modifications. The expanded role of system engineers in the areas of system operational familiarity and modifications will also aid in ensuring that current operational practices are included in design changes.

(5) THE DATE WHEN FULL COMPLIANCE WILL BE ACHIEVED Operation of the service building and auxiliary building ventilation systems, as currently configured to discharge through VENTVENT #2, is in compliance with UFSAR Section 9.13.4. Releases attributable to duct leakage from the service building ventilation system have been analyzed to be within the limits provided in 10CFR20 and the Surry Power Station Technical Specifications.

The return of the ventilation systems to the normal operational configuration cannot be completed until VENTVENT #1 is returned to service. This date is projected to be December 15, 1990; however this schedule may be impacted by radiation monitor availability. We will confirm the scheduled completion of this work by September 30, 1990 and notify your staff if our projected date is unachievable.

Work required to bring the VENTVENT #2 effluent sampling system into full compliance is presently being performed. Evaluation of the sample system to obtain representative samples is scheduled for completion by February 28, 1990. Installation of the control program enhancements for the Kaman Monitor is expected to be completed by May 1, 1990, subject to receipt of the software package from the vendor.