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 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
Page Last Reviewed/Updated Tuesday, March 09, 2021
Page Last Reviewed/Updated Tuesday, March 09, 2021