United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 86-42: Improper Maintenance of Radiation Monitoring Systems

                                                          SSINS No: 6835  
                                                          IN 86-42         

                                UNITED STATES
                           WASHINGTON, DC 20555

                                June 9, 1986

                                   MONITORING SYSTEMS 


All nuclear power reactor facilities holding an operating license (OL) or a 
construction permit (CP) 

Purpose and Summary: 

This notice is issued to alert licensees to the potential for defeating the 
safety function associated with radiation monitoring systems by not properly
adhering to established surveillance and maintenance procedures A recent 
event at a BWR, when an electrical jumper was inadvertently left in place 
after a planned surveillance, led to failure to maintain secondary 
containment integrity during irradiated fuel movement 

It is expected that recipients will review the information for applicability
to their maintenance and surveillance program and consider actions, if 
appropriate, to preclude similar problems at their facility However, 
suggestions contained in this notice do not constitute NRC requirements; 
therefore, no specific action or written response is required 

Previous Related Correspondence 

Information Notice No. No 83-23, "Inoperable Containment Atmosphere Sensing 
  Systems," April 25, 1983 

INPO Significant Event Report, 35-83, "Compromise of Secondary Containment 
  Integrity," June 9, 1983 

Information Notice No. No 83-52, "Radioactive Waste Gas System Events," 
  August 9, 1983 

Information Notice No. No 84-37, "Use of Lifted Leads and Jumpers During 
  Maintenance or Surveillance Testing," May 10, 1984 

Description of Circumstances: 

On November 18, 1985 the Cooper Nuclear Station was in a shutdown condition 
(reactor coolant temperature less than 212 F and vented) with acceptance 
testing for a plant design change in progress When this testing failed to 
provide for the required Group VI isolation (various containment isolation 


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engineered safety feature (ESF) initiations), the licensee investigated and 
discovered that electrical jumpers were installed in the reactor building 
(RB) ventilation radiation monitors (VRM) auxiliary trip units These 
jumpers prohibited a Group VI isolation by a high radiation signal from the 
RB VRM The jumpers were immediately removed and the NRC was promptly 
notified as required by 10 CFR 5072 

The licensee's subsequent investigation revealed that the electrical jumpers
had been installed on November 13, 1985 by an instrument and control 
technician during a routine surveillance procedure to functionally test the 
VRM These jumpers are used to prevent trip and equipment operations during 
the required functional/calibration testing The technician had signed off 
the procedural step requiring jumper removal (before actually removing the 
electrical jumper) and then started checking control room annunciator and 
trip signal status The technician then became involved in other unrelated 
craft work and forgot to go back and remove the jumpers 

On November 18, 1986, before discovery of the jumpers, 18 irradiated fuel 
bundles were loaded into a spent fuel shipping cask Failure to properly 
implement the surveillance procedure for operability checks of radiation 
monitors rendered inoperable the automatic initiation of the standby gas 
treatment system (SBGTS) and automatic isolation of the reactor building 
upon receipt of a high radiation signal This degraded condition lasted 
approximately 5 days However, control room annunciators and instrumentation
that would provide warning to operators of any high radiation problems 
remained operational during the 5 days Manual-start of the SBGTS and 
reactor building isolation capabilities from the control room remained 
available during the event 


This event clearly demonstrates that the level of attention given to the 
procedural controls for the maintenance of radioactive monitoring systems 
providing ESF actuation can be significantly improved While there were no 
actual radiological consequences of this event, the NRC took escalated 
enforcement actions (issued civil penalty) to emphasize the importance of 
correctly performing surveillance procedures on systems designed to mitigate
or prevent accidents Attachment No 1 contains 6 summaries of related 
events taken from the Licensee Event Report files Further examples of how 
improper maintenance practices have degraded radiation monitoring systems 
are provided in the listed Previous Related Correspondence section 

The Cooper Station initiated the following corrective actions to prevent 

1   All temporary modifications (eg, electrical jumpering, fuse removal) 
     performed by the involved technician since October 5, 1985 were 
     independently verified 

2   Site management stressed the importance of procedural adherence--sign 
     off the procedural step after completing the required action 

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3   All surveillance procedures requiring temporary modifications to system
     or plant components were reviewed for deficiencies, and these 
     procedures will be modified to provide for independent verification to 
     ensure that temporary modifications are removed and the 
     system/component is fully restored to operational status 

No specific action or written response is required by this information 
notice If you have any questions about this matter, please contact the 
Regional Administrator of the appropriate regional office or this office 

                                   Edward L Jordan, Director 
                                   Division of Emergency Preparedness 
                                     and Engineering Response 
                                   Office of Inspection and Enforcement 

Technical Contacts: James E Wigginton, IE 
                    (301) 492-4967 

                    Roger L Pedersen, IE 
                    (301) 492-9425 

1   Event Summaries 
2   List of Recently Issued IE Information Notices 

                                                             Attachment 1  
                                                             IN 86-42      
                                                             June 9, 1986  
                                                             Page 1 of 2   

                               EVENT SUMMARIES

Unplanned Gaseous Release (Connecticut Yankee, PWR) 
LER 85-025 
Event Date: 9/19/85 
Cause: Personnel Maintenance Error 
Abstract: With the plant operating at 100 percent power, a main stack high 
          radiation alarm was received during routine scheduled maintenance 
          on a pressure actuated valve in the gaseous waste stream The 
          unplanned release occurred through an isolation valve 
          inadvertently left open, allowing the on-line waste gas decay tank 
          a release path The maintenance tag-out procedure correctly 
          required the isolation valve to be isolated, but the operator shut 
          the wrong valve The total noble gas release was approximately 20 
          curies (about 14 percent of technical specification limit) 
          Licensee corrective action included clearly relabeling associated 
          valves and discussion of the event with operation staff 

Containment Radiation Monitor Isolated (Byron 1, PWR) 
LER 85-026 
Event Date: 2/28/85 
Cause: Improper Valve Position 
Abstract: With the reactor at zero percent power, a containment radiation 
          monitor used for required reactor coolant leakage detection was 
          inadvertently left isolated for 72 hours from containment after 
          maintenance on an associated valve Abnormal in-leakage at the 
          monitor caused normal-range readings on RM-11 console in the main 
          control room (leakage was later repaired) Licensee corrective 
          action included implementing administrative controls to ensure 
          system integrity/proper restoration after completion of 
          maintenance activities 

Liquid Radwaste Effluent Monitor Isolated (Cooper, BWR) 
LER 84-008 
Event Date: 6/09/84 
Cause: Monitor Discharge Valve Shut 
Abstract: A liquid discharge occurred without required continuous radiation 
          monitoring because the liquid effluent radiation monitor was 
          isolated No discharge limits were exceeded Two days before the 
          event, a technician apparently shut the radiation monitor outlet 
          valve during maintenance without permission or knowledge of 
          operations personnel As corrective actions, the licensee revised 
          controlling procedures and informed all plant operators of the 

                                                             Attachment 1  
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                                                             Page 2 of 2   

Off-Gas Stack Monitor Inoperable (Cooper, BWR)
LER 84-006
Event Date: 4/18/84 
Cause: Personnel Error 
Abstract: With the reactor at 70 percent power, the off-gas stack effluent 
          sampler was found inoperable  The sampler was drawing air from 
          the surrounding off-gas filter building ambient atmosphere instead 
          of sampling the plant stack effluent The event resulted from a 
          chemistry technician failing to follow the approved procedure for 
          changing the inline particulate filter/iodine cartridge (routine 
          operation) In addition to making appropriate supervisors and all 
          chemistry technicians aware of the event, the licensee revised and 
          clarified the governing procedure to prevent recurrence 

Liquid Radwaste Auto-Isolation Valve Inoperative (Hatch 1, BWR) 
LER 82-093 
Event Date: 11/07/82 
Cause: Jumper Installed 
Abstract: During a liquid radwaste discharge, the licensee discovered that 
          the radiation monitor auto control (provides isolation signal upon
          high radiation) to the discharge isolation valve was inoperable 
          However, the monitor's alarm function remained operable An 
          electrical jumper used during corrective maintenance had not been 
          removed after the work was completed 

Containment Atmosphere Radiation Monitors Isolated (FitzPatrick 1, BWR) 
LER 81-061 (Rev 1) 
Event Date: 8/21/81 
Cause: Containment Isolation Valve Isolated 
Abstract: The NRC resident inspector discovered that during normal 85 
          percent power operations the containment isolation valves for the 
          containment atmosphere gaseous and particulate monitoring system 
          had been shut for approximately 22 hours With this loss of 
          monitoring capability, the technical specifications require a 
          reactor hot shutdown within 12 hours The event occurred because a 
          surveillance procedure did not direct the operator to re-open the 
          isolation valves following the surveillance activities As a 
          corrective action, the licensee corrected the subject procedure 
          and reviewed all other surveillance procedures for similar 

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