IR 05000369/1986030

Insp Repts 50-369/86-30 & 50-370/86-30 on 860921-1020. Violation Noted:Nuclear Control Operator Initiated RHR Flow Through HX W/O Component Cooling Water Flow Present,Inducing Series of Water Hammers

ML20213F908
Person / Time
Site:	McGuire, Mcguire
Issue date:	11/05/1986
From:	William Orders, Peebles T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20213F888	List: IR 05000369/1986030 ML20213F886 ML20213F894
References
50-369-86-30, 50-370-86-30, NUDOCS 8611170242
Download: ML20213F908 (9)

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UNITED STATES o NUCLE'AR REGULATORY COMMisslON

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Report Nos.: 50-369/86-30 and 50-370/86-30 Licensee: Duke Power Company 422 South Church Street Charlotte, NC 28242 Docket Nos.: 50-369 and 50-370 License Nos.: NPF-9 and NPF-17 Facility Name: McGuire 1 and 2 Inspection Conducted: September 21 - October 20 1986 Inspector: .

/ . A //' 5' 4C W. T. Orders,' Seni'or Resident Inspctor Date Signed Accompanying Personnel: S. F. Guenther Approved by: /, //- IM T. A. Peebles, Section Chief Date Signed Division of Reactor Projects SUMMARY Scope: This routine, unannounced inspection involved the areas of operations safety verification, surveillance testing, maintenance activities, event follow-up, emergency exercise evaluation and environmental monitorin Results: Of the areas inspected, one violation was identified in the areas of facility operations.

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, REPORT DETAILS Persons Contacted Licensee Employees

• T. McConnell, Plant Manager

• B. Travis, Superintendent of Operations

• D. Rains, Superintendent of Maintenance

• B. Hamilton, Superintendent of Technical Services

, * Sample, Superintendent of Integrated Scheduling

• E. McCraw, License and Compliance Engineer

• N. Atherton, Compliance Other licensee employees contacted included construction craftsmen, technicians, operators, mechanics, security force members, and office personne ,

• Attended exit interview Exit Interview The inspection scope and findings were summarized on October 24, 1986, with those persons indicated in paragraph 1 above. The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspector during this inspection.

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The following violations were discussed: (369/86-30-01) failure to follow procedure (paragraph 3a) and (369,370/86-30-02) failure to test VC/YC

, (paragraph 3b), which is considered Licensee Identified and is close The following unresolved item was discussed: (369,370/86-30-04) lab sink i

driven to turbine building (paragraph 8).

The following inspector followup item was discussed: (370/86-30-03) valve

stroke testing for 2CF-23 (paragraph Sb).

I An inspector followup item (369,370/86-30-05) was identified by an in office

review of the licensee's evaluation of the source of tritiated water in the sanitary waste lagoon on October 3,198 This evaluation is added as paragraph 10 to this repor . Licensee Action on Previous Enforcement Matters (Closed) Unresolved Item 369/86-28-03, Apparent procedural noncompli-ance resulting in component cooling water (KC) system water hammer.

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The licensee completed its investigation of this incident and concluded that it was caused by personnel error on the part of the nuclear control operato KC flow meter 1KCP5670, which is normally used to

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measure KC flow through the 1A residual heat removal (ND) heat exchanger, was pegged low and bore an orange work request sticker pending repair. The operator throttled open valve 1KC-56A to admit KC flow through the ND heat exchanger and relief upon a perceived flow increase on the KC train "B" pump discharge flow meter (1KCP5540) to satisfy the procedural requirement. The operator failed to verify the KC cross-train header valve alignment required to ensure cross-train cooling flow. This incident is resolved as an apparent violation of Technical Specification 6.8.1, in that the operator failed to comply with the requirements of Enclosure 4.5 of OP/1/A/6200/04, " Residual Heat Removal" (369/86-30-01),

b. (Closed) Unresolved Item 369, 370/86-28-09, Complete investigation of the failure to perform control building ventilation / chilled water (VC/YC) system post-modification functional verification. Further discussions were held with the licensee regarding their post-modification / maintenance testing programs and the fundamental similarity of this incident (i.e., failure to perform any functional verification on the VC/YC system prior to declaring train "A" operable following the installation of interposing relays on July 2,1986) to an earlier incident (i.e., failure to perform adequate post-modification testing of the upper head injection accumulator system in April 1984)

cited in NRC Inspection Report Nos. 50-369/84-34 and 50-370/84-3 Both cases illustrated deficiencies in the post-modification testing program, in that the affected systems were restored to an operable status prior to demonstrating the ability to perform their intended functions. The corrective actions for the earlier violation should have prevented the VC/YC incident, however, the administrative control system was defeated through personnel erro This procedural non-compliance was facilitated by a loophole in the retest program which allowed the Construction and Maintenance Department (CMD) to process work requests to implement nuclear station modifications (NSMs)

without designating on the work request that a retest or functional verification was require This resulted in operations personnel erroneously accepting control of the assumption that no retest was require The failure to test VC/YC was a violation of 10 CFR 50, Appendix B, Criterion XI, which requires that a test program be established to assure that all testing required to demonstrate that structures, systems and components will perform satisfactorily in service is identified and performed in accordance with written test procedure However, after a thorough review of the safety significance of the event, and with the knowledge that the event meets the criterion allowed by 10 CFR 2, Appendix C, for licensee identified violations, no Notice of Violation will be issued. (LIV 369,370/86-30-02).

c. (Closed) Unresolved Item 369/86-28-07, Complete an investigation of concerns regarding operator actions taken to block the low pressurizer pressure safety injection signal during the rapid depressurization transient which occurred during the pressurizer code safety valve

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(INC-1) failure on September 2,1986. Under normal circumstances, without operator action, a decrease in pressurizer pressure below 1845 psi would be indicative of a loss of coolant accident (LOCA) and would result in an engineered safeguard features (ESF) actuation / safety injection (SI). This ESF signal can be manually blocked by the operator to allow normal cooldown and depressurization of the reactor coolant system af ter pressure is decreased below 1955 ps The Controlling Procedure for Unit Shutdown (0P/1/A/6100/002) is the only procedure which authorizes the low pressurizer pressure SI signal to be blocke Discussions with the control room operators revealed that during the transient, control room annunciators alerted them that a safety valve was open and led them to believe that an NC system pipe rupture had not occurred. One of the control room operators' primary concerns during the incident was the safety of Operations and Health Physics personnel who, as part of the test in progress, were conducting NC system leakage inspections inside containment. The only egress path from containment led directly past the pressurizer relief tank (PRT), which accepts and condenses the discharged steam from any open safety valve. If PRT pressure had increased to 100 psi, the rupture disc would have burst allowing the INC-1 discharge to escape directly to the containment atmosphere jeopardizing the safety of the personnel on containment and possibly blocking their exit pat The operators stated that they evaluated the available parameters, including pressurizer pressure, pressurizer level, safety valve annunciators, subcooling margin, and decay heat load / power history, and decided that the safety of personnel inside containment was best served by blocking the low pressurizer pressure SI signal . The operators indicated that they were unsure how an SI initiation would affect the length of time remaining prior to PRT rupture disc failure and that ample subcooling margin existed to allow subsequent manual SI initiation if INC-1 had not reseated prior to reaching saturation pressure at approximately 1200 ps Pursuant to 10 CFR 50.54(x), as implemented by Operations Management Procedure 1-2, "Use of Procedures", it is authorized to deviate from a Technical Specification and/or other requirement if deemed necessary to protect health and safety under emergency condition After a thorough review of the circumstances surrounding the incident, and discussions with the Region II staff, it is concluded that the operations personnel were justified in their actions to invoke the allowances of 50.54(x). Unresolved Item 369/8C-28-07 is herewith l close _ - - - --

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_e Unresolved Items *

One new unresolycd item w'esiidentified during this report period and is discussed in paragraph . Plant Ophrations l '

The inspection staff revied oW.t operations during the report period, to verify conformance with tpplicable regulatory requirements. Control room ,

logs, shift supervisors legs, shift turnover records and equipment removal '

and restoration records were routinely perused. Interviews were conducted with plant operations, maintenance, chemistry', health physics, and performance personne Activities within the control room were monitored during chifts and at shift- I changes. Actions and/or activities observed were conducted as prescribed in' ,

applicable station administrative directives. - The complement of licensed personnel on each shift met or exceeded the miri mumi required by Technical Specification '

Plant tours.taken during the reporting period included but were not limited to the turbine buildings, auxiliary building, units l'and E electrical ~ ~

equipment ' rooms, units 1 and 2 cable spreading rooms, and the statim yard zone inside the protected are During the piant tou r's , ongoing activities, eekeeping, security, equipment status and radiation _ control practices e a observe Unit 1 Operations Unit I remained on line for the entire reporting period, with the exception o? an approximate one-day shutdown fol'.owing a reactor trip at 3:50 p.m., on September 24, 1986. A malfunction in the digital electro-hydraulic (DEH) control system caused all four turbine governor valves to close. The rapid . loss of load caused primary system temperature and pressure to' iricrease and resulted in a reactor trip on

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high pressurizer pressure. The plant's response vas essentially normal during the trip, the faulty DEH circuitry was bypassed, and the unit was returned to service on September 2 _

Two brief power redu'ctions occurred during the reporting period. Power was decreased to about ,50% from Septeniber 21-22, to investigate problems with the DEH and feedwater pump turbine conteel syste.ts; On September 27, power was decreased to about C6% in response to a tube leak in the A2 feedwater. heater. The faulty heater string was isolated and full power operation was resume ;,

• An Unresolved Item is a matteKabout which more information is required to determine whether it is acceptable or' may involve a violation or deviatio .

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5 Unit 2 Operations Unit 2 operated at essentially 100% power throughout the reporting period. Power was briefly reduced on October 17, when the licensee discovered that the packing on 2CF-23, a feedwater flow regulating valve, had been adjusted without subsequently performing a valve stroke timing test as required by the licensee's inservice testing progra The feedwater regulating valves function as backup feed header isolation valves, but are not required to be operable by the Technical Specifications, as the main feedwater header isolation valves are. The licensee, nevertheless, declared 2CF-23 inoperable and commenced a plant shutdown pending a ruling from the NRC regarding the testing requirements for the valve. NRC, Region II informed the licensee that it was not the intent of the valve testing program to force a plant to shutdown in order to fully stroke test a flow modulating valve whose packing had been adjusted. Unit 2 was returned to full power and 2CF-23 will be stroke tested at the next available opportunit This will be maintained as an Inspector Follow-up Item (IFI 370/86-30-03). Surveillance Testing i The surveillance tests categorized below were analyzed and/or witnessed by the inspector to ascertain procedural and performance adequacy and conformance with applicable Technical Specifications. The selected tests witnessed were examined to ascertain that current written approved procedures were available and in use, that test equipment in use was calibrated, that test prerequisites were met, system restoration completed and test results were adequat Two cases of inadequate surveillance testing were identified in this inspection period and are detailed belo PT/1/A/4252/01A Motor Driven CA Pump A Performance Test PT/1/A/4252/01B Motor Driven CA Pump B Performance Test PT/1/A/4350/15B DG 1B Periodic Test PT/1/A/4601/02 Protective System Channel II Functional Test PT/1/A/4601/04 Protective System Channel 4 Functional Test PT/1/A/4208/01A Containment Spray 1A Performance Test PT/1/A/4208/01B Containm W Spray 1B Performance Test PT/1/A/4401/01A Component C oling Train 1A Performance Test PT/1/A/4403/01A Nu'. t M Sr ice Water Train 1A Performance Test PT/2/A/4601/01 Pretr cth. :.ystems Channel 1 Functional Test PT/2/A/4208/01A Containment Spray 2A Performance Test PT/2/A/4204/01B Residual Heat Removal 2B Performance Test PT/2/A/4209/01B Centrifugal Charging Pump 2B Performance Test PT/2/A/4206/01B Safety Injection Pump 2B Performance Test

, PT/2/A/4206/01A Safety Injection Pump 2A Performance Test PT/2/A/4252/01A M/D Aux. Feedwater Pump 2A Performance Test I

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At < 11:34 a.m. , on September 23, the licensee was informed that, the labora, tory analysis of a representative sample of carbon taken from' the Unit 2 VA., system failed to meet the 'one percent (maximum) menthyl iodine penetration criteria pursuant to Technical Specification (TS) surveillance test requirement 4.7.7. This plv.ed Unit 2 in a 24-hour shutdown

, limiting condition for operation (LCO), pending replacement of the VA system g charcoal filter mediu The licensee promptly informed the resident inspectors of the problem and of their desire to obtain temporary emergency relief from the TS LCO. Communications were initiated with the NRC in Region II and the Office of Nuclear Reactor Regulation, during which the licensee presented justification fcr continued Unit 2 operation for 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> beyond the expiration of the 24-hour LCO. This justification was documented in a Duke Power Company (DPC) letter dated September 25, 1980, to the Regional Administrator, Region I The NRC reviewed the licensee's justification for continued Unit 2 operation, found it acceptable, and granted the 96-hour relief prior to 11:34 a.m., on September 24, 1986. The Unit 2 VA system charcoal was successfully replaced and tested prier to expiration of the extended LC0 allowed outage' time, and system operatiility was restore '

In their letter of September 25, 1986, DPC committed to a good faith effort to improve VA system performance in the emergency core cooling system pump rooms on the 695' elevation, with a goal of establishing a negative 0.25" water gauge pressure relative to atmospheri The resident inspectors witnessed a dennonstration of this capability on October .

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On September 30, 1986, it was determined that surveillance requirements for ground water monitoring station 2 (WILT 5070) were not completed as required when the instrument was not functionally verified subsequent to a temporary modificatio On October 14, 1986, it was determined that the quarterly surveillance for certain nuclear service water valve stroke timing had not been performed

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within the surveillance interva Without going into the details associated with the above two instances, they singularly and collectively constitute violations of their respective Technical Specification surveillance requirement However, given that in report 369, 370/86-28, a violation was issued for similar inadequacies and your response along with proposed corrective actions have not been received, another violation, will not be issue !

You are urged, however,' to scrutinize your proposed corrective actions to assure they envelop the above two instance '

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, Maintenance Observations Ma1ntenance activities were analyzed and/or witnessed by the resident inspection staff to ascertain procedural and performance adequacy and conformance with applicable Technical Specification The activities witnessed were examined to ascertain that, where applicable, current written approved procedures were available and in use, that prerequisites were met, equipment restoration was completed and maintenance results were adequat No violations or deviations were identifie . Event Follow-up On October 2,1986, the licensee discovered, during its routine sampling program, that some tritiated water had been disposed of in the plant's sanitary waste treatment (WT) system and had been transported to the waste water collection basin (WWCB). The licensee originally believed that the water had been inadvertently and improperly disposed of, possibly after some decontamination efforts, via one of the floor drains or sinks on the clean side of the auxiliary building change roo However, after further investigation, the licensee determined that the contaminated water had originated from a sink in the health physics shift laborator the laboratory had originally been planned for environmental sample analysis, and the sink drain was routed to the WT syste This was demonstrated by performing dye tests during the startup phase of the " an The laboratory had since been placed in service as a health physics shift lab, and the fact that the sink was not designed for contaminated waste disposal was overlooked. The matter will be tracked as Unresolved Item 369, 370/86-30-04 pending completion of an inspection by a region based inspecto . Annual Emergency Response Exercise The McGuire Nuclear Station Annual Emergency Preparedness Exercise was conducted on October 14-15, 198 The resident and senior resident

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inspectors assisted the Region II Emergency Preparedness Section in evaluation exercise performance by serving as observers in the control room and technical support center, respectivel The details regarding the exercise will be addressed separately in Inspection Report No. 50-369, 370/86-2 . Tritium in Sanitary Waste Lagoon (90713)

On October 7,1986, the licensee notified the resident inspector and RII that tritium had been detected in the October 3,1986, weekly sample from the facility's sanitary waste treatment lagoon (per Technical Specification Table 4.11-1). Confirmatory samples taken October 6 and 7, 1986, also showed tritium present. The highest sample was the sample taken October 3, and was analyzed at 1.84 x 10-5 mci /ml (1.84 x 104 pCi/1).

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At approximately 10:00 a.m. on October 7,1986, a conference call was conducted between the licensee, the State of North Carolina, NRR and R11 to discuss means of disposing of the material. The normal plant input to the sanitary waste system is approximately 50,000 gallons per day and licensee representatives stated that there had been no previous record of tritium contamination of the waste system, based on analyses of weekly samples. The outfall of the waste lagoon goes to a collection basin with an area of approximately seven acres and an estimated volume of 10,000,000 gallons. No liquids have been dischanged to the environment from the collection basin since prior to the detection of tritium in the sanitary sewer syste Samples of collection basin water since October 3,1986, have been below the lower limit of detection (LLD) of approximately 8 x 10-6 mci /m Since tritium cannot be removed from water or concentrated, since the highest concentration observed to date was less than the 10 CFR Part 20, Appendix B. Table II, Column 2 value, and since dilution by the collection basin water, uncontaminated plant input, and mixing with river water would further dilute any tritium present to levels several orders of magnitude less than the MPC, all parties to the discussion agreed to permit the licensee to dispose of the contaminated water to the river as a one-time exception to the NPDES permit, with the condition that an additional dilution of approximately 6,000 gallons per minute of uncontaminated service water would be utilized to further reduce the concentration of tritium prior to releas The licensee calculated that potential radiation doses to maximally exposed downstream water users as a result of the release of this material would be on the order of 10-7 to 10-8 mrem /yr, compared to natural background annual radiation exposures of 100 to 125 mrem /y Plant Technical Specification 3.11.1.1 provides that concentration of radioactive material released in liquid effluents to unrestricted areas shall be limited to the concentrations specified in 10 CFR Part 20, Appendix B, Table II, Column 2; this value for tritium is 2 x 10-5 mci /ml (or 2 x 104 pCi/l).

Licensee representatives indicated that their investigation of the source of the tritium contamination had failed to disclose the source or cause. A licensee representative postulated that one or more persons may have inadvertently dumped a small quantity of tritiated waste water into either a normally clean drain system or into a commode in a washroom. NRR calculated that the quantity of tritium found represented approximately 45 gallons of undiluted primary coolant and concluded that the licensee's postulation of a small number of inadvertent disposals of small volumes of tritiated wastes would not adequately account for the amount of tritium detected in the waste treatment lagoo (0pened) Inspector Followup Item (50-369, 370/86-05).

Review licensee evaluation of source of tritiated waste contributing to detection of tritium in the sanitary waste lagoon October 3,1986.

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