United States Nuclear Regulatory Commission - Protecting People and the Environment



MEMORANDUM FOR:     B. H. Grier, Director, Region I 
                    J. P. O'Reilly, Director, Region II 
                    J. G. Keppler, Director, Region III 
                    K. V. Seyfrit, Director, Region IV 
                    R. H. Engelken, Director, Region V 

FROM:               James H. Sniezek, Director, Fuel Facility and Materials 
                      Safety Inspection, IE 

SUBJECT:            IE Circular NO. 79-21: PREVENTION OF UNPLANNED RELEASES 
                    OF RADIOACTIVITY 

The subject Circular is transmitted for issuance on October 19, 1979. The 
Notice should be issued to all holders of Power Reactor Operating Licenses 
and Construction Permits. Also enclosed is a draft copy of the transmittal 
letter. 


                                        James H. Sniezek 
                                        Director 
                                        Fuel Facility and Materials 
                                          Safety Inspection 

Enclosures: 
1.   Draft Transmittal Letter 
2.   IE Circular 79-21 
.

(Draft Transmittal letter to all power reactor facilities with an operating 
license or construction permit). 

                                                     IE Circular No. 79-21 

Gentlemen: 

Enclosed is IE Circular No. 79-21, "Prevention of Unplanned Releases of 
Radioactivity," which provides information on inadvertent releases/on-site 
spills of radioactivity. Should you have any questions related to the 
enclosed suggested preventive measures, please contact this office. 


                                        Signature 
                                        (Regional Director) 

Enclosures: 
1.   IE Circular 79-21 
2.   IE Circulars Issued 
       in the Last Six Months 
.

                                            Accession No.:  7908220128 
                                             SSINS: 6830 

                              UNITED STATES 
                      NUCLEAR REGULATORY COMMISSION 
                   OFFICE OF INSPECTION AND ENFORCEMENT 
                          WASHINGTON, D.C. 20555 
                                     
                            October 19, 1979  

                                                      IE Circular No. 79-21 

PREVENTION OF UNPLANNED RELEASES OF RADIOACTIVITY 

Numerous incidents of unplanned releases of radioactivity have been reported
to the NRC within the past few months. These incidents of leaks, overflows 
and spills have resulted in contamination of areas outside of plant 
buildings. The attached table provides you with summary information on these
events, their apparent causes, the radiological consequences and the 
corrective actions. 

We believe that a number of these incidents could have been avoided and 
preventive actions for these types of unplanned releases should be 
instituted by all reactor licensees. Based on the reported incidents, the 
following preventive measures can minimize the occurrence of such events. 

1.   Review of procedures for transfer of radioactive liquids. Errors in 
     written procedures have led to mistakes in valve line-ups and tank 
     overflows. Written procedures, including check lists for valve lineups,
     should be developed and followed for operations which could cause 
     spills of radioactivity. Management controls, including audits, should 
     be employed to assure verbatim compliance with such procedures. 
     
2.   Review of "as built" systems having the potential of inadvertent 
     releases because of design or construction errors. Consider items such 
     as: 

     a.   Tank overflows should be routed to liquid radwaste tanks. 

     b.   Storm drains should be located away from areas with a high 
          potential for spills. 

     c.   Consideration should be given to drip pans under equipment, such 
          as pumps and valves, from which leakage is expected. 

     d.   Cofferdams should be installed under doors to areas with a 
          potential for radioactive spills. 

     e.   Preoperational testing should verify that crossconnects do not 
          exist that would permit radioactivity to flow from operating 
          unit(s) to unit(s) under construction. 

3.   Periodically functionally test and perform inspections to verify 
     integrity of systems that could cause an inadvertent release. Excessive
     wear and corrosion degradation have occurred in valves, seals and 
     piping systems to cause leaks. New permanent and temporary piping 
     systems should be 
.

IE Circular No. 79-21                                 October 19, 1979  
                                                       Page 2 of 2 

     hydrostatically tested prior to first use. Underground piping should be 
     periodically hydrostatically tested. Preventive maintenance programs 
     should be implemented and identified problems, such as leaking 
     equipment and plugged floor drains, should be promptly repaired. 
     
No written response to this Circular is required. If you require additional 
information regarding this subject, contact the Director of the appropriate 
NRC Regional Office 

Enclosure: 
Recent Events of Radioactive 
  Contamination 


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