United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 91-16: Unmonitored Release Pathways from Slightly Contaminated Recycle and Recirculation Water Systems at a Fuel Facility

                               UNITED STATES 
                       NUCLEAR REGULATORY COMMISSION 
              OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS 
                          WASHINGTON, D.C.  20555 

                               March 6, 1991 


Information Notice No. 91-16:  UNMONITORED RELEASE PATHWAYS FROM 
                                   SLIGHTLY CONTAMINATED RECYCLE AND 
                                   RECIRCULATION WATER SYSTEMS AT A FUEL 
                                   FACILITY 


Addressees: 

All fuel cycle facilities. 

Purpose: 

This Information Notice is intended to alert addressees to potential 
problems resulting from using runoff water and process effluents, both 
contaminated with radioactive materials, in non-nuclear processes.  At one 
fuel facility, the use of these liquids resulted in a concentration and/or 
release of radioactive material, without an evaluation, to unrestricted 
areas.  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 U.S. Nuclear Regulatory Commission (NRC) 
requirements; therefore, no specific action or written response is required.

Description of Circumstances: 

A fuel facility's recycle water system was used to provide water for 
non-contact cooling of plant systems, the fire protection system, sanitary 
facilities, a grit blaster, and gaseous effluent scrubbers.  Makeup water 
for the system was partially obtained by collecting rain water from roof and 
storm sewer drains.  The makeup water became contaminated by particulate 
fallout from effluent discharges onto the buildings and the nearby ground 
areas.  As a result, the recycle water system became contaminated. 

The licensee had routinely analyzed the recycle system water for gross alpha 
radioactivity.  However, the licensee failed to evaluate either the 
processes which used recycle water and could concentrate the uranium or the 
release pathways from the recycle water system which released excess water 
during heavy rain storms.  The pathways included overflows from the system 
reservoir, the cooling tower, and the roof and storm sewer drains.  The 
runoff eventually drained to a nearby river without an analysis for 
radioactivity.  As a result, unmonitored release pathways existed for low 
levels of radioactivity. 

Another unmonitored release pathway for the recycle system was from the 
facility's fire protection system, which used recycle water as the supply 
source.  When the fire protection system's booster pumps were tested, the 
pumps discharged onto the open ground.  No samples were analyzed for 
radioactivity before these 

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                                                            IN 91-16
                                                            March 6, 1991
                                                            Page 2 of 3 


releases.  Additionally, recycle water was periodically provided to a local 
fire department to refill the water-storage tanks in its fire truck, without 
analysis for radioactivity.  The licensee was aware that the recycle system 
was slightly contaminated but thought that the transfers of radioactively 
contaminated water were allowed because the concentrations were below the 10 
CFR Part 20 release limits. 

Another example of an unmonitored release pathway from the recycle system 
was from gaseous effluent scrubbers that used the slightly contaminated 
recycle water for particulate removal.  The gaseous exhaust from the 
scrubbers had been routinely sampled for nitrous oxide but not for 
radioactivity.  Additionally, contaminated scrubber water from two fume 
scrubbers had been discharged to a nonradioactive holding pond.  The pond 
was part of the licensee's nonradioactive liquid waste treatment facility, 
and the introduction of the contaminated water may have caused radioactive 
contamination of the pond. 

Recycle water was also used in the licensee's zirconium and copper recovery 
processes.  The recycle water was used in the zirconium recovery process as 
part of the cleaning process.  After recovery, the zirconium was then 
packaged and sold to various offside vendors without testing for radioactive 
contamination.  In the copper recovery process, the recycle water was used 
in the associated scrubber for gaseous effluents.  Since contaminated 
recycle water was used in the scrubber, the transfer of water to the 
recovery system could have contaminated the copper recovery system and the 
final copper oxide product.  Without testing for radioactive contamination, 
the product was sold to offsite vendors for use in various products. 

Another water system used for the scrubber water was the recirculation water 
system.  During 1984, the licensee installed the recirculation water system 
which diverted a portion of the final effluent for use in the liquid waste 
treatment facility.  This effluent contained low concentrations of 
radioactive isotopes that were below 10 CFR Part 20 release limits.  The 
recirculation water was used in the liquid waste treatment facility to 
prepare the lime slurry for use in both the radioactive and the 
nonradioactive waste treatment operations to neutralize the acidic solutions 
and to precipitate fluorides and metals such as aluminum, chromium, 
zirconium, and uranium.  The precipitated sludge from the radioactive waste 
treatment was shipped offsite for disposal as low-level radioactive waste.  
The precipitated sludge from the assumed nonradioactive water treatment 
system was buried onsite in a State-permitted landfill.  However, this 
sludge contained radioactive contaminants from the recirculation water lime 
slurry, and the State-permitted landfill was not authorized to receive 
radioactive material. 

The licensee has initiated and/or completed corrective actions for both the 
recycle and the recirculation water systems to eliminate the sources of 
radioactive contamination and to evaluate all release points.  The licensee 
has eliminated the use of radioactively contaminated recirculation water in 
the recovery operations and ceased onsite burial of the radioactively 
contaminated sludge.  Further corrective actions will include 
characterization of the onsite burial areas. 
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                                                            IN 91-16
                                                            March 6, 1991
                                                            Page 3 of 3 


Discussion: 

Licensees are reminded that they must make surveys to assure compliance with 
10 CFR 20.301 which describes authorized means of disposal of licensed 
material in waste and must make surveys to assure compliance with 10 CFR 
20.106 which limits the yearly average concentration of radioactive material 
in air or water discharged to unrestricted areas.  Furthermore, licensees 
are reminded that changes in plant design must be evaluated to determine 
whether the changes will result in the unmonitored release of radioactive 
material to unrestricted areas. 

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(s) listed below or the appropriate NRR project 
manager. 




                                   Richard E. Cunningham, Director
                                     Division of Industrial and 
                                     Medical Nuclear Safety 
                                   Office of Nuclear Material Safety 
                                          and Safeguards


Technical Contacts:  Susan S. Adamovitz, Region II
                     (404) 331-4774

                     Edwin D. Flack, NMSS
                     (301) 492-0405


Attachments: 
1.  List of Recently Issued NMSS Information Notices 
2.  List of Recently Issued NRC Information Notices 

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