IR 05000498/1989035

Insp Repts 50-498/89-35 & 50-499/89-35 on 890814-18. Violation Noted.Major Areas Inspected:Inadvertent Radioactive Contamination of Portions of Auxiliary Steam Sys Condensate Return Flow Path & Inorganics Basin

ML20248C710
Person / Time
Site:	South Texas
Issue date:	09/26/1989
From:	Gagliardo J, Garrison D, Hunter D, Kelley D, Ricketson L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20248C693	List: IR 05000498/1989035 ML20248C690 ML20248C703
References
50-498-89-35, 50-499-89-35, NUDOCS 8910030554
Download: ML20248C710 (10)

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APPENDIX B U.S. NUCLEAR REGULATORY COMMISSION

REGION IV

NRC Inspection Report: 50-498/89-35 Operating Licenses: NPF-76 50-499/89-35 NPF-80 Dockets: 50-498 50-499

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Licensee: Houston Lighting & Power Company (HL&P)

P.O. Box 289 Wadsworth, Texas 77483 i Facility Name: South Texas Project (STP) Electric Generating Station, Units 1 and 2 Inspection At: STP, Wadsworth (Matagorda County), Texas Inspection Conducted: August 14-18, 1989 Inspectors: [/b-_%_

1. R. Hunter, Senior Reactor Inspector, Date Z/ Of Operational Programs Section, Division of Reactor Safety

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D. L. Kelley. ReactorlInspeg or, Operational Date /

Programs Section, Divisi6c)of Reactor Safety l

[ . . / .]il!ll l~l\ Y D. L. Garrison', Resident Inspector, Project Date Section D, Division of Reactor Projects i

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. T.'Ricketson, Radiation Specialist, Reactor

.9-Ed Date Programs Branch, Division of Radiation Safety andpfeguards

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Approved: i

'J.\E. Gagliardo, Chief, Operational Programs Dete /

Section, Division of Reactor Safety 891003cO34 g pO9;;g

,F Dh ADOCK 05000493 FDL

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-2-Inspection Summary Inspection Conducted August 14-18, 1989 (Report 50-498/89-35; 50-499/89-35)

Areas Inspected: Nonroutine, unannounced inspection of the inadvertent radioactive contamination of portions of the euxiliary steam system condensate return flow path and the inorganics basi .,

i Results: Within the area inspected, one violation was identified regarding three examples of the failure to follow procedures (paragraphs 3.2, 3.3, and 3.5).

The specific event occurred as a direct result of an operator failing to close .

two process valves as required by the approved procedure. Even though the l chemical operator entered the discrepancy in the log book at the time the- l valves were left open, the gas stripper / liquid waste evaporator was operated again in an incorrect lineup on August 12, 1989. The manual valves remained open (mispositioned) for a period of 4 days (August 10-14,1989).

Additionally, the shift supervisor and the chemical operations foreman established the flow path for the auxiliary steam system condensate return I

system to the inorganics basin. This flow path was not specified in an approved procedure. The failure to follow approved procedures, including the improper processing of procedure changes, and the failure to followup on the :

l identified deficiency in a timely manner resulted in the contamination event

and presented the potential for a more serious event. These operating practices were not considered to be fully acceptabl Once the potential contamination was identified by the licensee on August 14, 1989, the event was pursued expeditiousl The event revealed less than acceptable operating practices and a number of-design weaknesses in the areas of system interfaces, flow paths, and radiation monitoring. The licensee temporarily susper.ded the operation of the gas stripper and liquid waste evaporator units for both Units 1 and 2 as a precautionary measure pending the completion of the event evaluation. .At the conclusion of the inspection on August 18, 1989, the licensee was continuing to evaluate the lessons learned from the event and develop specific and generic corrective action _ _ _ _ -

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DETAILS Personnel Contacted

• G. E. Vaughn, Vice President, Nuclear Operations

• S. L. Rosen, Vice President, Nuclear Engineering and Construction

• W. H. Kinsey, Plant Manager

• M. R. Wisenburg,. General Manager, NSRB

• J. R. Lovell, Manager, Technical Services

• D. J. Denver, Manager, Nuclear Engineering

• R. A. Gangluff, Manager, Chemical Operations and Analysis

• T. J. Jordan, Manager, Plant Engineering

• V. R. Albert, Manager, Systems Engineering -

• A. C. McIntyre, Manager, Support Engineering I

• M. A. McBurnett, Manager, Licensing )

1 *G. L. Parkey, Manager, Integrated Planning and Scheduling

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• W. J. Jump, Manager, Maintenance

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• S. M. Dew, Manager, Nuclear Plant Mechanical Maintenance

• J. . W. Loesch, Manager, Plant Operations

• J. D.' Green, Nuclear Assurance .

• D. A. Leazar, Manager, Reactor Support j

• J. A. Burack, ISEG

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• P. L. Walker, Senior Licensing Engineer

• Denotes these attending the management exit on August 18, 1989.

I Other license 1 personnel were contacted during the inspectio ; ' Background

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The processing and cleanup of radioactive liquid at the South Texas Project (STP) included a typical gas stripper and liquid waste evaporator package unit._ The system function was to degassify and' concentrate radioactive liquid l

2.1 Prior to the series of events, which occurred on August 10, 1989, during l the normal shutdown' activities associated with the gas stripper and liquid i

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waste evaporator (GS/LWE), the operation of the system appeared to be

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routin .2 The shutdown of STP, Unit 1, in early August for the scheduled refueling outage, included a planned change in the reactor coolant chemistry (pH),

which caused a release of corrosion products from the reactor coolant system (RCS). The cleanup of these products from the RCS, including the use of the GS/LWE unit, was planned in order to decrease the radiation levels encountered during the refueling outage. Additionally, STP Unit 1 had experienced minor fuel rod leakage during the first cycle of operation. These two factors resulted in an abnormally high level'of radioactivity constituents and concentrations in the liquid waste syste J

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.4 2.3 The' auxiliary steam (process steam) was being supplied from the operating plant, STP Unit 2. The initial design for STP included supplying auxiliary steam from the auxilf ary boilers, Unit 1, or Unit 2; and provided for the auxiliary steam condensate to be returned to the STP Unit 1 plant (main condenser), to liquid waste, or to the auxiliary boiler deareator. The design did not include the condensate return to the STP Unit 2 plant'(main condenser). Consequently,.the condensate return was discharged to the inorganics basin via the auxiliary boiler deareator grab sample manual valv .4 The radioactive liquid feed piping to the gas stripper and liquid waste i evaporator unit had no isolation valves external to the unit. During routine evolutions the inlet feed piping to the package unit was pressurized and an improper valve lineup or leaking valves could have resulted in the transfer of radioactive liquid into the shutdown strippe . Event Review The inspectors reviewed selected drawings, procedures, and records; performed field inspections; and interviewed selected personnel in order to fully understand the sequence of events and verify the general facts regarding the even The inspection included operator interviews, the review of the boiler I startup procedures, the review of the startup and draining of the auxiliary boiler condensate systems, and the walkdown of the systems involved in this event. The systems that were walked down included the condensate feed lines (from the Liquid Waste Condensate Package 1A through the Boiler No. 12 condensate feed), deareator, boiler steam and head drums, system drains, the inorganics basin; and the neutralization basi The inspectors utilized the procedure for the auxiliary steam system 1 (OPOP02-AS-0001, Revision 7) and the.following drawings during the system !

walkdowns:

60160F20008, Revision 14 " Auxiliary Steam"

60160F10001, Revision 11. " Auxiliary Boiler Condensate"

60310F20016, Revision 9. " Wastewater Collection" ;

5R309F05027 Revision 13. " Condensate Return (LWPS)" )

t 3.1 The inspection revealed that during the period between August 6 and 9, l 1989, the GS/LWE had been operated normally, processing radioactive liqui .2 On August 10, 1989, however, at about 8:10 a.m., the GS/LWE was shutdown,

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with noted exceptions, in accordance with Procedure IPCP13-WL-0007, " Waste Evaporator Operations," Revision 4. Because of contamination in the gas '

stripper area, the operator made the decision not to close certain valves until the health physics department perfomed a survey of the are Manual Valves 1-XWL-392 and 1-XWL-349 were not closed as required by l Steps 4.3.6.1 and 4.3.6.4.b, respectively. The air purge valves to the -

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-5-gas stripper rotometer were not closed. Additionally, the Auxiliary Steam (process steam) Supply Header Manual Valve 1-WL-145 was closed because of steam leakage through the normal stripper flow control valve (FV-4300).

The operator noted these deviations from the procedure in the logboo The fact that Manual Valves 1-XWL-392 and 1-XWL-349 were in the open position established a flow path from the normal supply header via Valve 1-XWL-349 to the GS/LWE through the shutdown gas stripper feed pump and the gas stripper into the auxiliary steam / condensate return system through open Valve 1-XWL-392. The normal operating pressure of the auxiliary steam system (150 psig) and Manual Valve WL-145 being in the closed position apparently limited the extent of the intrusion of the radioactive liquid into the auxiliary steam system. The fsilure to isolate the instrument air to the rotameter did not have an impact on the even Document review, discussions, and field walkdowns revealed that the two manual valves (1-XWL-349 and 1-XWL-392) were located in the gas stripper room lower level, which was contaminated because of a process liquid lea The contamination required additional precautions to be taken during routine entrance into the area to manipulate the valves. Also, these manual valves were not easily accessible because of their physical locatio Notwithstanding, the actual conditions in the stripper room at the time, the manual valves could have been properly positioned. The valves, which were not closed, remained open until August 14, 1989, 3 p.m., when they were closed by the license During the period from 8:10 a.m. until 4:45 p.m., on August 10, 1989, a direct pathway through the gas stripper into the auxiliary steam system and condensate return piping was established. This pathway allowed the transport of radioactive liquid into the previously uncontaminated systems during routine operations of the waste processing system (WPS).

Records review and discussions with licensee personnel revealed that no procedure change request was processed, providing for management review and epproval of the deviation from the established procedure during the routine shutdown activities associated with the GS/LW '

Technical Specification 6.8.1 requires that procedures shall be established and implemented covering the activities recommended in !

Appendix A of Regulatory Guide 1.33, Revision 2 February 197 i Section 7.a.(1) of Appendix A addresses the collection, filtering, evaporating and concentrating, and demineralizing of 11ouid radioactive waste system l Administrative Procedure OPGP03-ZA-0010. " Plant Procedure Compliance, Implementation, and Review," Revision 11, implemented this requiremen !'

Step 3.1, " Compliance with Procedures," of OPGP03-ZA-0010 specified that procedures shall be strictly adhered to and changes to procedures shall be riade in accordance with OPGP03-ZA-0002 " Plant Procedures." ,

Administrative Procedure OPCP01-ZA-0002, " Plant Chemical Procedures and 1 l

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Forcis," Revision 2, Section 3. " Procedure," Step 3.1, also required that l 1 plant chemical procedures shall be prepared and revised in accordance with l Procedure OPGP03-ZA-000 l l

Departmer.t Procedure 1 PCP13-WL-0007, " Waste Evaporator Operation,"

Revision 4. Steps 4.3.6.1 and 4.3.6.4.b specified that Manual Valves 1-XWL-392 and 1-XWL-349 be closed for gas stripper shutdown (Step 4.3.6).

The failure to implement the procedures as required by Technical

Specification 6.B'.1 is an apparent violation (498/8935-01; 499/8935-01) of l the above requiremen .3 During the period between 1:16 p.m. and 6:45 p.m., on August 10, 1989, the condensate polishing regeneration waste collection tank (CPRWCT) was aligned and pumped to the Waste Monitor Tanks (WMT) via the liquid waste l processing system auxiliary demineralizers. This activity caused the ,

l pressurization of the normal supply header to the GS/LWE to about 94 psig I and resulted in the transfer of liquid waste water, via the open Manual Valves 1-XWL-349 and 1-XWL-392 into the gas stripper and the auxiliary steam / condensate return flow path. The condensate return was aligned to the auxiliary boiler deareator, which then began to experience a level I increase and high level alarms. Interviews revealed that the flow path to I the inorganics basin via the auxiliary boiler deareator grab sample line l was established by the shift supervisor and chemical operations foreman to allow manual control of the dearcator water level because a return flowpath to Unit 2 was not provided in the design. The existing procedure would, therefore, call for the water to be dumped to the floor drains, but the decision was made to not dump the condensate return drains to the waste system, which would require further processing of the waste. The supervisors i believed the excess water in the deareator was clean and decided to use j the grab sample line as a normal drain path even though it was not included in the procedure for operating the auxiliary steam system (OPOP02-AS-0001, Revision 7), the liquid waste processing system steam and condensate returns (IPCP13-WL-0010, Pevision 5), or the inorganics basin (0PCP11-NC-0001, ;

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Revision 3). No procedure change request had been processed, providing management review and approval of the use of the specific manual drain path to the inorganics basi The failure to establish an adequate procedure and to implement the existing procedure is another example of the violation cited in paragraph 3.2. i (498/8935-01; 499/8935-01)

3.4 During shift relief and turnover activities on August 10, 1989, at about '

4 p.m., the operator noted a gas stripper high level and high pressure alarm. At 4:45 p.m., the operator closed the normally open Manual Valve 1-XWL-347 in the GS/LKE normal supply header to isolate the GS/LWE from the header. Manual Valve 1-XWL-347 was in series with Manual Valve 1-XWL-349, which had been previously left in the open positio Interviews revealed that the operator had drained the gas stripper, returning it to nonnal level and pressure conditions. The licensee

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L -7-estimated that about 1500 gallons of radioactive liquid waste had been pumped'through.the shutdown gas stripper, through the local auxiliary steam piping (via the open Manual Valve-1-XWL-392) and the' auxiliary steam system condensate receiver tank, into the auxiliary boiler deareator tank, and was subsequently drained into the inorganics basin via the 2-inch Manual Grab Sample Valve 0-AS-023 .5 The GS/LWE unit was subsequently operated on August 12, 1989, during the period from 1:50 p.m. to 5 p.m. The operating procedure'for the GS/WLE unit again specified the manipulation of Manual Valves 1-XWL-349 and 1-XWL-392 during the unit startup and shutdown. The valves were apparently not closed again as required during the unit shutdown. Records,

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review and discussions revealed that no procedure change request had been processed, providing management review and approval of.the startup and shutdown of the GS/LWE in a manner different than'that specified by the approved procedure._ The valves not being positioned in accordance with the approved procedure could have resulted in the transfer of additional radioactive liquid into the auxiliary steam and condensate drain systems, i resulting in more extensive contamination.

l The failure to implement Procedure IPCP13-WL-0007, " Waste Evaporator Operations." on August 12,1989, by not closing Manual Valves 1-XWL-392 and 1-XWL-549 is another example of the violation of Technical Specification 6.8.1 cited in paragraph (498/8935-01;499/8935-01)

3.6 The inspection also revealed that the package boiler and the No.12 auxiliary boiler had been " fired" on August 13 and 14, respectively. The two " firings" were performed to preset the' firing mechanism controls and did not require any condensate feed; thus, the boiler and steam side of the boilers did not receive any of the contaminated water from the auxiliary boiler deareato The inspector verified that the valves on the auxiliary and package boiler side of the boiler feed pumps were closed during the period that contaminated water was in the condensate return system. The contaminatio in the condensate return was contained at the closed valves. After the

" firing" of the No. 12 auxiliary boiler on August 14, 1989, the boiler drums were gravity drained through the floor into the inorganics basi The package boiler was not draine Subsequent to the " firing" and draining of the No. 12. auxiliary boiler on August.14, 1989, the deareator was also drained by gravity through Manual Valve AS-0231 (2-inch grab sample line) into the inorganics basin via the 8-inch cast iron drain header. (see paragraph 3.3)

The review of the records and discussions with the licensee revealed that water was last pumped from the inorganics basin to the neutralization basin on August 10, 1989, prior to the contamination of the inorganics basin with radioactive liquid waste.

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-8-l The inspection revealed that the drawing associated with the inorganics !

basin was not up-to-date in that the pumps and piping from the inorganics j basin to the neutralization basin were not included on the drawing. The i licensee had revised the applicable Operating Procedure OPCP11-NC-0001, {

Revision L The apparent discrepancy on the drawing was brought to the licensee's

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attention during the inspection. The licensee noted that the specific-discrepancy and the program weakness would be evaluated. The inspectors l have no further questions regarding this ite .7 lhe NRC radiation specialist reviewed selected licensee activities regarding the occurrence and performed a number of reviews and check The following activities were performed by the inspector:

Independent measurements on the condensate' drain lines, auxiliary boiler package, and inorganic basin to confirm the licensee's external radiation measurements;

Review of the licensee's radiological posting and controls;

Review of the results of the offsite dose calculations performed by the licensee to confirmed that if all the material had been released to unrestricted areas, it would not have resulted in significant doses to individuals;

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Review of the results of the licensee's surveys and samples to confirm that radioactive material had not been released from the protected area; and

Obtained a simultaneous grab sample with the licensee from the main cooling reservoir to independently confirm the result At the close of the inspection, the inspector was continuing to monitor I the licensee's activities including the plan for pumping the contaminated liquid from the inorganics basin to the liquid waste processing system in the spent fuel building truck bay within the radiation control area.

l 3.8 The licensee's imediate action to the event was to isolate and post, as I contaminated, all known areas and equipment affected by the liquid wast The licensee also examined and sampled all conceivable release pathway No additional contaminated areas were discovered.- )

Having bounded the affected areas and equipment, the licensee began examining methods to restere'the affected equipment and areas to normal

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operation and access. The first item considered was the transfer of the contents of the inorganics basin to the liquid waste processing syste The licensee proposed to accomplish this by installation of temporary hose from the inorganics basin to the radioactive waste processing i syste l l

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-9-The licensee conducted studies to determine the best method of' flushing the affected piping and equipment. In consonance with this effort, temporary procedures were under development to control all cleanup evolution ~

The flushing plan receiving the most consideration at the time the inspection concluded was to flush all piping and equipment to the inorganics basin and to pump the liquid waste to the liquid waste processing system.

l The final step in recovery was planned to be decontamination of the inorganics basin. The NRC will cortinue to monitor the decontamination efforts of the license . Conclusions i

The inspection revealed that the contamination event did not result in any i

significant release of radioactive material outside the previously uncontaminated (clean) systems, nor was there a release of detectable

! radioactive material outside the' owner controlled area to the environment.

l The surveys and samples performed by the licensee and reviewed by the-

! inspectors following the event on August 14, 1989 . revealed that the radiation levels and external contamination were minimal and controlle The review of the licensee dose calculations confirmed that if the event had resulted in a release of the limited amount of liquid radioactive waste to the unrestricted area, no license limits would have been approached. Exposures of site personnel or the public to radiation would have been minima The cause of the event was the failure to follow established procedures, resulting in Manual Valves 1-XWL-349 and 1-XWL-392 being'left in the open position by the operators. This failure established a flow p th from the liouid radioactive waste processing system into the auxiliary steam and condensate return system and inorganics basin. Although the location of the manual valves and the local contamination and radiation levcis, in the area of the valves was a deterrent to cperating the valves, the plant

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staff should have understood the importance of the valves and closed the mar,ual valves in accordance with the established procedur A number of apparent system design weaknesses were identified during the inspection, including the specific valve locations, the lack of isolation valves and check valves for system isolation, the lack of radiation monitoring of the condensate return system, and the lack of certain needed flow paths. The licensee's corrective actions included the review of the specific and generic implications of the noted design weaknesse At the conclusion of the inspection, the licensee's immediate corrective actions appeared to be acceptable. The licensee was developing a recovery plen for the liquid waste process system and inorganics basi i

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-10-5.: Management Exit

. The inspectors met with Messrs. C. E. Vaughn, S. L. Rosen, W. II. Kinsey, and other members of the licensee's staff at the end of the inspection on August 18, 1989 (denoted in paragraph 1). The inspectors met with licensee representatives during the week and were provided a routine update of the licensee's findings. During the exit meeting'the inspectors summarized the scope of the inspection and presented the inspection findings. The licensee noted that the event would be discussed in the Region IV NRC office on August 25, 1989, as part of a previously scheduled meeting. The licensee did not identify any proprietary information related to this inspection effort.

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