IR 05000320/1989005

Insp Rept 50-320/89-05 on 890603-0818.Major Areas Inspected: Defueling & Decontamination Activities,Including Proper Implementation of Radiological Controls,Housekeeping Measures & Actions on Previous Insp Findings

ML20247L005
Person / Time
Site:	Three Mile Island
Issue date:	09/07/1989
From:	Cowgill C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20247L001	List: IR 05000320/1989005 ML20247K996
References
50-320-89-05, 50-320-89-5, NUDOCS 8909220090
Download: ML20247L005 (11)

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U. S.-NUCLEAR REGULATORY COMMISSION REGION 1-Report N /89-05 Docket No.- 50-320 License N DPR-73- Priority --

Category C Licensee: GPU Nuclear Corporation

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P. O. Box 480 Middletown, Pennsylvania 17057

. Facility Name: Three Mile Island Nuclear Station, Unit 2 -

Inspection At: Middletown, Pennsylvania Inspection Conducted: Jure 3, 1989 - August 18, 1989

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Inspectors: F. Young, Senior Resident Inspector D. Johnson, Resident Inspector T. Moslak, Resident Inspector R. Brady, Resident Inspector

' Approved by- on/ i/7/89 C. Cowg1 ,CMf Date Reactor o'ec w Section 4B-Division Reactor Projects Inspection Summary:

Areas Inspected: Routine safety inspection was conducted by site inspectors of defueling and decontamination ar.tivities, including the proper implementa-tion of radiological controls, housekeeping measures, and licensee actions on previous inspection finding Results: Licensee personnel continue to conduct defueling activities in a safe controlled manner. Two operational events occurred during this report period. The licensee staff responded appropriately to the events; and long term corrective actions are being evaluated and/or implemented. These events were handled in a prudent and safe manner. Previous inspection findings were closed based on inspector review for current applicability and licensee actions to resolve the issue o 890913 gD" ADOCK 05000320 FDC

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TABLE OF CONTENTS Page 1.0 Overview . . . . . . . . .. . . . . . . . . . ... . . . . . I 1.1 Licensee Activities .. . . . . . . . . . . . . . . . . I 1.2 NRC Staff Activities. . . . . . . . . . . . . . . . . I 1.3 Persons Contacted . . . . . . . . . . . . . . . . . . 2 2.0 Licensee Events (NIP 71707) . . . . . . . . . . ..... 2 2.1 Alarm on Nuclear Instrumentation-NI-2 . . . . . . . . 2 2.2 Failure of Unit Substation Transformer 2-46 . . . . . 3 3.0 Licensee Actions on Previous Inspection Findings (NIP 92701/92702). . . . . . . . . . . . . . . . . . . . 4 3.1 (Closed) Violation (50-320/87-04-02) Contaminated Pallet Found in Restricted Area . . . . . . . . . . . 5 3.2 (Closed) Inspector Follow Item (50-320/87-04-03) High Concentration of Airborne Contamination While Scabbling the Seal Injection Valve Room (SIVR). . . . 5 3.3 (Closed) Violation (50-320/87-09-02) Liquid Radwaste Spill During Hydrostatic Test Of Processing System . . . . . . . . . ......... 5 (Closed) Inspe: tor Follow Item (50-320/87-15-03)

Unlocked High Radiation Area Door . ......... 6 3.5 (Closed) Unresolved Item (50-320/88-01-01):

Laborer Found to Be Inattentive To His Duties . . . . 6 3.6 (Closed) Violation (50-320/88-09-01) Grinding of Concrete Surfaces Resulting in High Concentrations of Airborne Radioactive Materials in Reactor Building. . . . . . . . . . . . . . . . . . . . . . . 7 3.7 (Closed) Violation (50-320/88-09-02) Worker Falls Into Working Slot of Shielded Work Platform . .... 8 4.0 Management Meeting (NIP 30703) . . . . . . . . . . . . . . 9

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DETAILS 1.0 Overview 1.1 Licensee Activities During this report period, defueling crews continued to remove core debris from the lower head of the vessel using pick and place techniques and air lifting equipment. Debris was also removed frca the reactor vessel hot legs using a specially designed scraper /vacu-using tool. Approximately 15,000 lbs. of material remain in the vtssel. The majority of this material is located in the annular space between tt e baffle plates and core former walls. Removal of the core baffle plates is required to defuel this area. To remove the baffle plates, 864 bolts, that secure the plates, must be removed. To date, defueling crews have removed all but 33 of the 864 bolts, either by using a remotely operated hydraulic wrench, or drilling out the bolts. The remaining bolts will be removed upon completion of high pressure (cavijet) flushing nperations. This flushing is to break up material that is adhering to surfaces of the core internal Present schedules indicate that reactor vessel defueling will be completed by this fal .2 NRC Staff Activities The purpose of this inspection was to assess licensee activities during defueling and decontamination activities. This assessment was made through observations of licensee activities, interviews with licensee personnel, and review of applicable document The inspectors reviewed licensee's procedures implementing control on several interfacing systems with the reactor vessel to assure adequate controls were in place to prevent uncontrolled boron dilu-tion. The inspectors also reviewed instrument calibration, switching and tagging of valves, approval authority, and responsibilities of the operations personne NRC staff inspections use the acceptance criteria and guidance of NRC Inspection Procedures (NIP's). These NIP's were annotated in the Table of Contents to this repor i

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1.3 Persons Contacted During this inspection, the following key licensee personnel provided information in the development of the inspectors' finding *J. Byrne, Manager, TMI-2 Licensing

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• P. Carmel, Waste Management Manager

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• W. Conaway, Radwaste Support Manager

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L. Edwards, Quality Assurance (QA) Auditor

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• D. Ethridge, Radiological Engineering Manager

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• C. Incorvati, Audit Manager

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• E. Juteau, Radioactive Material Coordinator

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G. Kuehn, Site Operations Director., TMI-2

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"S. Levin, Defueling Operations Director

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• W. Marshall, Manager, Plant Operations, TMI-2

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• M. Roche, Director, TMI-2

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• R. Rogan, Director, Licensing & Neclear Safety, TMI-2

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• E. Schrull, TMI-2 Licensing Engineer

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• R. Sieglitz, Manager, Wa;te Management

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R. Wells, Licensing Engineer

• Attended the final management meetin .0 Licensee Eveats 2.1 Alarm on Nuclear Instrumentation-NI-2 Scraping / Vacuuming Defueling operations on "B" hot leg were temporarily suspended on August 9, 1989 at 7:53 pm when the "High NI-1/NI-2 Counts" alarm was received in the control room. Nuclear Instrumentation Source Range channel, NI-2, had spiked from a nominal reading of 1.5 counts per second (cps) to 11.5 cps for a duration of less than 1 minute. The alarm cleared immediately when the countrate returned to approximately 1.5 cp The operators in the centrol room noted the other source range NI channel, NI-1, showed no increase in countrate, nor did the reactor building criticality monitors indicate an upscale deflecticn. At the direction of the Shift Supervisor, the Radiological Controls Depart-ment performed surveys in the area of the shielded work platform to establish if any changes occurred in the Reactor Buildings' radio-logical conditions. No changes in radiation levels or airborne l

concentration were noted. Additionally, the shift supervisor veri-fied that the boron concentration and water level of the reactor coolant system remained con: tan _ _ _ _ _ _ _ -_ _ _ _ _ _ _ _ _ . ___-_______ -_ _-_ __-________________- ___ __-__-_- _ _ _ - - -

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Upon determining that plant conditions were-stable andlthat the spike did not exceed 12.5 cps which would require implementation of the Emergency and Abnormal Procedure,.4210-EAP3220.01, " Unanticipated Neutron Increase and/or Boron Dilution", defueling activities on the

"B" hot leg resume :The Site Operations Department provided the licensee's Safety Review Group (SRG) with the details of the incident so that a technical evaluation could be performed. Upon examination of these details, the SRG could not determine the exact cause of the inciden However, two probable causes are under investigation. The first is that the increased countrate was caused by an electrical spike in the NI-2~ circuitry. The second is that the increased countrate was caused by the ongoing defueling evolution. NI-2 is in close proxi-mity of the "B" hot leg, and the scraping / vacuuming operation caused

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fine material to be suspended near the detector. Following the defueling evolution, the steady state countrate on NI-2 decreased to 0.5, which indicated that re-suspended fuel debris was the most pro-

, bable cause for the change in NI-2 readings.

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The inspector concluded that operations personnel acted appropriately l in establishing if plant safety was affected by the incident. The inspector also determined that the incident is receiving the appro-priate level of technical review to establish its caus .2 Failure of Unit Substation Transformer 2-46 Failure of the 4160V/480V Unit Substation Transformer (USS) 2-46 occurred on July 25, 1989 at 4:58 pm. The apparent cause was degradation of the insulation on the primary side of the transformer resulting in a ground fault in the transformer. USS 2-46 provides electrical power to the Auxiliary and Fuel Handling Building (AFHB)

ventilation supply and exhaust fans ( AH-E-9A/B, AH-E-10C/D), the Reactor Coolant System (RCS) Boronometer, and various Reactor Building receptacles supplying power to building cameras and auxi-liary lightin Components powered by transformer 2-46 were without power from 4:58 pm to 5:20 pm on July 25, 1989. Power was restored by cross-tieing to the USS-2-36 transformer which has the capacity to supply the USS-2-46 electrical loads in addition to its ow Redundant AFHB ventilation supply and exhaust fans and RB receptacles were available and powered from buses 2-35 and 2-4 Technical Specification 3.8.2.1.1 requires that the A.C. Buses listed in Recovery Operations Plan (ROP) Section 4.8.2.1.1 be operable and energized with tie breakers open between redundant busses. With less than the listed complement of A.C. busses operable (BUS 2-46 is U--_-___-_----_---. _ _ _

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listed in R0P 4.8.2.1.1) the action statement' requires returning the inoperable bus to service within eight hours. Since the action statement could not be met, the licensee is reporting the event under the provisions of 10 CFR 50.73 (a) (2) (1) (B).

The licensee has considered three long term options to recover from this event. The first option is to replace the damaged transforme However, a new transformer requires a one year lead time for the vendor, and there are no suitable spare replacements within the GPUN

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system. The second option is to rebuild the damaged transforme This option was undesirable due to high cost (comparable with a new transformer),10_ week lead time, and difficulty of performing a radiation release survey which would require dismantling the 2-46 transformer on site. GPU Nuclear currently plans to enter Facility Mode 2* by December 31, 1989, at which time TS requirement 3.8.2. is no longer applicable, Based on repair / replacement time to restore USS-2-46 to operable status, the liter.see has determined it is not prudent to pursue these two opt 3cni. Therefore, the licensee has chose to pursue the third optica, to change the Recovery Operations Plan to allow the current bus configuration. Relief from the RGP requiren,ent 4.8.2.1.1 relating to busses 2-36 and 2-46 will allow the breakers between transformer pairs 2-35/2-45 to remain closed in the event that the redundant bus pairs cannot be reenergized within the eight hour time requirement of T.S. 3.8.2. In the event of fa'. lure of USS-2-36 transformer and subsequent loss of busses 2-46 and 2-36, the redundant bus pair (2-35/2-45) would be tied together and one of these transformers (USS-2-35 or USS-2-45) would be iso-lated from the bus and used to replace the failed USS-2-36. This would restore power to bus pair 2-36/2-4 The proposed revision does not increase the probability of occurrence or consequences of an accident or malfunction of equipment important to safety previously evaluated in the Safety Analysis Report (SAR)

because sufficient power to HVAC systems would be available. Any potential accident germane to the proposed revision to the R0P is bounded by a previous analysi Through review of the licensee's actions, proposed R0P change and discussions with licensee representatives, the inspector had no furcher questions on the licensee's proposed resolution of the issue and actions taken. The inspector concluded this issue has minor safety significanc .0 Licensee Actions on Previously Identified Items (NIP 92701/92702)

The inspector reviewed the licensee's action on previous inspection findings to ensure that the licensee took appropriate action in response to the findings or by self-initiative and that the licensee's action was timel *

Fuel removed from vessel, but some still on-sit _ _- -_ _- __-_-___ __ _-- _ _ _ _ _ _ _ _ _ - - _ - _ - _ _ - _ - _ _ - _ _ _ _ _ _ _ _ - _ - _ _ _ _ _ - _ _ _ - _ _ - _ _ _ _ _ _ _ -____ -

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3.1 (Closed) Violation (50-320/87-04-02) Contaminated Pallet Found in Restricted Area As described in the licensee response (4410-87-L-0126) to the Not. ice

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of Violation for this event, an extensive survey of areas outside the Radiological Control Area was performed to identify any addi-tional contaminated material. This survey identified several items that had small amounts of contamination that were in excess of the current TMI-2 Release limits. However, these items were released to non-radiological control areas during_a time period when less restrictive release limits were in effec The inspector determined that the licensee took immediate positive actions to strengthen the controls for transfer of ccataminated materials and that these short and long term actions were implemented as described in Licensee Event Report (LER-005). The inspector determined that the above corrective actions provide reasonable assurance that a similar event will not occur. The inspector had no further questions on this ite .2 (Closed) Inspector Follow Item (50-320/87-04-03) High Concentration of Airborne Contamination While Scabbling the Seal Injection Valve Room (SIVR)

The inspector determined that the actions taken by the licensee following a critique of this event were effective to preclude a recurrence. Scabbling* and other decontamination activities have been completed in the Seal Injection Valve Room in preparation for placing this area into a Mode 4 conditio The inspector had no additional questions concerning this ite .3 (Closed) Violation (50-320/87-09-02) Liquid Radwaste Spill During Hydrotest Of Processing System As detailed in Inspection Report 50-320/87-09, a 200 gallon spill of processed water occurred in the Auxiliary Building during prepara-tions to transfer resins from the "A" Spent Resin Storage Tank to a solidification liner. The spill was a result of an unconnected hose in the system. The cause of this event was the failure of contractor personnel to comply with Procedure 4231-0PS-3233.02, " Operation of the Chem-Nuclear Cement Solidification Unit 125," and Procedure 4231-0PS-3233.01, " Assembly and Disassembly of the Chem-Nuclear Cement Solidification Unit No. 125." Both of these procedures require a hose inspection to be performed prior to sediment transfer operation *

Removal of approximately " of concrete floor or wall surfac i

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.6 As a result of this event, the following corrective actions have been taken by the license The contractor personnel-involved in the event have been counseled regarding the absciute necessity to comply with procedural require-ment A Temporary Change Notice (TCN-2) to Procedure 4231-OPS-3233.01 was issued. This TCN reiterates the requirement to verify system con-figuration prior to restart after the system is disassembled or reconfigur A Temporary Change Notice (TCN-2) to Procedure 4231-0PS-3233.02 also was issued. This TCN provided guidance for performing system verification. ~The TCN also requires an independent check of the hose and valve configuration by GPU Nuclear personne Procedures Change Requests (PCRs) to procedures 4231-0PS-3233.01 and 4231-OPS-3233.02 will be initiated to permanently incorporate the provisions of the above TCN System _ valves and hoses have been labeled and tagged to assist contractors in performing system verificatio The inspector determined that the above corrective actions provide reasonable assurance that a similar event will not occur. The inspector determined that the licensee had adequately evaluated the circumstances leading to this incident and implemented corrective actions. The inspector had no further questions on this ite .4 (Closed) Inspector Follow Item (50-320/87-15-03) Unlocked High Radiation Area Door The inspector reviewed the results of the licensee's investigation into the root cause of this inciden Included in this review was the Incident / Event Report, Safety Review Group Evaluation, and Security Investigation report. Through this review, the inspector determined that the licensee had adequately evaluated the circum-stances leading to this event and implemented corrective action The inspector had no further questions on this ite .5 (Closed) Unresolved Item (89-320/88-01-01): Laborer Found to Be Inattentive To His Duties Upon being informed of the inspection findings, the licensee per-formed an investigation to determine if the event was an isolated case or indicative of a programmatic problem. Although, a response was not required to the inspection report, the licensee chose to l_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - - - - - - - - _ - - - - - _ - - - - - _ _ - - _ _ - - - - - - - - - - - _ - _ - - -

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respond in a letter (4410-88-L-0058/0375P) dated April 19, 1988, to identify the actions taken to address this concern. Based upon a review of the licensee's actions and site inspections, the inspector concluded that the event was not a programmatic proble The inspector determined that the licensee had adequately evaluated the circumstances leading to this event and implemented corrective actions. The inspector had no further questions on this ite .6 (Closed) Violation (50-320/88-09-01) Grinding of Concrete Surfaces Resulting in High Concentrations of Airborne Radioactive Materials in Reactor Building On April 4, 1988 grinding of a highly contaminated block wall in the basement of the reactor building was started without performing an adequate assessment of the effects of that process on the level of airborne activity in the reactor building. As provided in the licensee's response (4410-88-L-0125) dated August 5, 1988, actions were taken to orevent a recurrence. These actions included counsel-ing the responsible decontamination operations supervisor for failing to perform the task in r. manner consistent with the intent of the Unit Work Instruct (UWI) and radiological assessment and for failing to communicate effectively with the Radiological Controls personne All of the decontamination operations supervisors were counselled concerning the need to recognize and comply with the intent of pro-cedures and the importance of analyzing work operations before pro-ceeding with alternative courses of action, out-of-sequence events, or unplanned steps to ensure proposed work is bounded by the existing ALARA review. The radiological engineers were sensitized to this situation via a memorandum that emphasized the rieed for specificity in procedures and ALARA reviews to avoid ambiguity concerning appli-cabilit Further actions to prevent recurrence include a memorandum to all UWI writers, task leaders, and engineers stressing the need for appro-priate specificity in defining tasks as a means of enhancing pro-

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work scope during planning and adequate consideration of the impact '

of a work scope change on personnel and radiological conditions. A l formal meeting was arranged for the Site Operations Director to

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discuss the recent events with Decontamination personnel and to emphasize the need for Radiological Controls approval before changing methods of operation. Finally, the Radiological Controls Field Operations technicians were instructed to be clear in communicating

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l 1 L s Through review of these actions and observations of decontamination operations the inspector determined that the licensee adequately responded to prevent a recurrence. The inspector determined that the licensee had adequately evaluated the circumstances leading to this event and implemented corrective actions. The inspector had no further questions on this ite .7 (Closed) Violation (50-320/88-09-02) Worker Falls Into Working Slot of Shielded Work Platform On May 23, 1988, a worker fell through an unguarded opening in the shielded work platform (SWP) as a direct result of not using proper safety equipment as required by procedur The licensee determined that the root cause of this event'was'a change of job scope without adequate pre planning. Specifically, the relocation of long-handled tools was undertaken during a lull in planned activities. This resulted in the individual working.in proximity to an unguarded, open slot 'n the work platform witSout a safety line attache Long-term corrective actions to prevent recurrer.ce induced the following: The Manager of Defueling Support issued a memorandum to all Defueling Support personnel specifically prohibiting anyone from working on the Shielded Work Platform without proper safety equipment, when any shield plugs are remove . Defueling. Support Supervisors were counseled concerning the need to explicitly follow procedures with particular emphasis to be directed to personnel safety issue Further, they have been enjoined by memorandum to think work operations through care-fully before proceeding with out-of-sequence or unplanned event . Briefings were conducted for entry personnel concerning proper techniques for rescue of persons from the Reactor Vessel in the unlikely event that a worker should fall between the rails of the slots on the Shielded Work Platfor Through review of the licensee's corrective actions and observations of defueling activities, the inspector determined that these actions have been effective to preclude a recurrence of a similar even _ _ _ _ - - _ _ _ _ _ _ - _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - _ _ _ _ _ _ _ -

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4.0 Manacement Meeting

, The inspector discussed the inspection scope and findings with licensee management periodically during the course of the inspection and at a final l meeting conducted July 18, 1989. Lictasee management attending the exit

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meeting are noted in paragraph The inspection results, as discussed at the meeting, are summarized in the cover page of the inspection repor Licensee representatives indicated that none of the subjects discussed contained proprietary or safeguards information.

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