Information Notice No. 83-27: Operational Response to Events Concerning Deliberate Acts Directed Against Plant Equipment

                                                          SSINS No.: 6835  
                                                          IN 83-27         

                               UNITED STATES 
                           WASHINGTON, D.C.  20555
                                May 4, 1983 

                                   DELIBERATE ACTS DIRECTED AGAINST PLANT 


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


This information notice is provided as a notification of events which may 
have involved deliberate acts directed against plant equipment and a lack of
station procedures concerning response by operating personnel. It is 
expected that recipients will review the information for applicability to 
their station procedures. No specific action or response is required at this 

Description of Circumstances: 

A review of recent operating reactor events indicates that some improper 
valve positioning and instrumentation irregularities may have involved 
deliberate acts directed against plant equipment in vital areas. The 
following is a brief account of these events. 

At the first facility, during routine operation, the Control Room Operator 
received a steam generator feedwater pump (SGFP) high vibration alarm. 
Subsequently the SGFP tripped and the operator immediately reduced turbine 
load to prevent the unit from tripping. The instrument valves on the low 
vacuum trip sensing line located outside vital areas were apparently 
deliberately repositioned resulting in the pump trip. The licensee concluded
that this deliberate act could have been a result of a labor dispute. 

At the second facility, during a routine operator tour at approximately 1:00
a.m., a manual valve was found shut in the common suction piping to the high
head safety injection (HHSI) pumps. The valve was immediately reopened. This
valve, which is checked by operators each shift, had been verified open at 
about 4:30 p.m. the previous day. The chain and padlock which secured this 
valve in the open position were missing. Additionally, on the previous day 
the manual suction isolation valves of the three auxiliary feed-water pumps 
had been found unchained and unlocked in violation of technical 
specifications requirements. These valves were found in their normally open 
position. The motive behind the actions was not proven, but the actions 
resulted in the HHSI system being inoperable. 


                                                              IN 83-27     
                                                              May 4, 1983  
                                                              Page 2 of 2  

These events, and events at other plants, demonstrate that the potential for
deliberate acts directed against plant equipment must be recognized. In the 
two above events the licensees were not totally prepared for operational 
followup actions. Other licensees may or may not be prepared to assess the 
situation and take necessary steps to assure operability of systems 
important to safety or make decisions concerning continued operation. 
Guidelines or procedures prepared by the licensee outlining a process for 
followup of both deliberate and inadvertent acts with respect to plant 
operation should be available. 

The guidelines and procedures should include a verification of the affected 
system(s) alignment, the system(s) control logic, and the availability of 
the system(s) main power supply. In addition interrelated systems should be 
inspected and selected safety-related electrical panels and cabinets, both 
in the plant and in the control room, may require a detailed inspection. If 
additional tampering is detected, the licensee should be prepared to make a 
decision on whether or not continued operation is justified and whether or 
not systems necessary for a safe shutdown are operable. 

Operational and security procedures to cope with radiological sabotage and 
other threats to safety must be developed in accordance with 10 CFR 
73.55(h)(1) and Appendix C of Part 73. The potential impact of any 
deliberate act directed against plant equipment must be evaluated, and 
actions taken to mitigate the anticipated safety consequences. 

No written response to this notice is required. If you have any questions 
regarding this matter, please contact the Regional Administrator of the 
appropriate NRC Regional Office, or this office. 

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

Technical Contact:  Paul R. Farron, IE 
                    (301) 492-4766 

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