Information Notice No. 90-12: Monitoring or Interruption of Plant Communications

                                UNITED STATES
                           WASHINGTON, D.C.  20555

                              February 28, 1990

Information Notice No. 90-12:  MONITORING OR INTERRUPTION OF 
                                   PLANT COMMUNICATIONS


All holders of operating licenses or construction permits for nuclear power 


This information notice is intended to inform licensees of the potential for 
monitoring and/or disruption of onsite radio communications at power 
reactors.  It is expected that recipients will review the information for 
applicability to their facilities and consider actions, as appropriate, to 
avoid similar problems.  However, suggestions contained in this information 
notice do not constitute NRC requirements; therefore, no specific action or 
written response is required. 

Description of Circumstances:

Between January 1989 and January 1990, an individual located offsite 
monitored and recorded onsite communications originating from the control 
room at Seabrook.  No security transmissions were recorded, only routine 
outgoing operational messages from the control room.  NRC representatives 
from both operations and safeguards randomly sampled portions of these taped 
communications.  No safeguards or other sensitive information which could 
have jeopardized safety was found to have been intercepted.  In an 
additional incident at Seabrook, an unauthorized transmission interrupted 
control room communications by transmitting on the same frequency.  It was 
not determined if the outside transmitting source was on or offsite.


Although no safety or security compromise appears to have been involved in 
the Seabrook incidents, they demonstrate the potential for such compromise, 
considering power reactor transmittal of routine operational and security 
radio messages on unencrypted (clear) radio frequencies, and the potential 
for interruption from external sources.  The intent of this notice is to 
call licensees' attention to the potential for similar type communication 
events at their facilities and the possible need for additional 
communications discipline for plant operations and security.  

                                                       IN 90-12
                                                       February 28, 1990
                                                       Page 2 of 2

In regard to plant security, 10 CFR 73.21 prohibits the transmission of 
safeguards information except by protected telecommunications circuits.  
This includes onsite and offsite radio and telephone communications.  
NUREG-0794, "Protection of Unclassified Safeguards Information," suggests 
that if protected (encrypted) frequencies are not used, routine radio 
transmissions between site security personnel be limited to message formats 
or codes that do not disclose facility safeguards features or response 

There are no specific requirements related to the security of radios and 
telephones for transmission of information on site in support of operations.  
Radios have been increasingly used as a means to provide more mobile and 
efficient communications links between plant operators.  However, radio 
communications are not private.  In view of the Seabrook event, addressees 
may wish to examine communications discipline and basic operations 
procedures that they now have. 

Various commercial scanners are available that can pick up site frequencies 
and are simple to operate.  An individual can listen in on all radio traffic  
for communications that are not secure.  Encrypted systems can help in 
overcoming the vulnerability of radio transmissions to exploitation.  
However, these systems may still be susceptible to monitoring. 

The unauthorized transmission at Seabrook demonstrates other methods that 
might exploit radio communications vulnerabilities.  Jamming and deception 
could be used in radio transmissions although this did not appear to be the 
intent at Seabrook.  

Federal law prohibits any person from intentionally and willfully causing or 
attempting to cause physical damage to a utilization facility or cause an 
interruption of normal operations through the unauthorized use of or 
tampering with the machinery, components, or controls of any such facility, 
and prescribes penalties for such attempts. (Section 236 of the "Atomic 
Energy Act") 

The sensitivity of onsite communications and the potential to aid malevolent 
acts varies considerably.  Proper communications discipline and basic radio 
operating procedures, commensurate with the operations and security 
significance of the communications, can lessen vulnerability to monitoring, 
jamming, and deception.  

This information notice requires no specific action or written response.  If 
you have any questions about the information in this notice, please contact 
the technical contact listed below or the appropriate NRR project manager.

                              Charles E. Rossi, Director
                              Division of Operational Events Assessment
                              Office of Nuclear Reactor Regulation

Technical Contact:  Michael S. Warren, NRR
                    (301) 492-3211

Attachment:  List of Recently Issued NRC Information Notices

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