IE Circular No. 79-21, Prevention of Unplanned Releases of Radioactivity
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
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
James H. Sniezek
Fuel Facility and Materials
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
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.
1. IE Circular 79-21
2. IE Circulars Issued
in the Last Six Months
Accession No.: 7908220128
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
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
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
Recent Events of Radioactive
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