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SSINS No.: 6835 IN 83-27 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C. 20555 May 4, 1983 Information Notice No. 83-27: OPERATIONAL RESPONSE TO EVENTS CONCERNING DELIBERATE ACTS DIRECTED AGAINST PLANT EQUIPMENT Addressees: All nuclear reactor facilities holding an operating license (OL) or construction permit (CP). Purpose: 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 time. 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. 8303040030 . 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 Attachment: List of Recently Issued IE Information Notices .
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