Information Notice No. 81-32: Transfer and/or Disposal of Spent Generators

                                                           SSINS No.: 6830 
                                                           Accession No.: 
                                                           IN 81-32 

                                UNITED STATES
                           WASHINGTON, D.C. 20555
                              October 23, 1981

Information Notice No. 81-32: TRANSFER AND/OR DISPOSAL OF SPENT 

Description of Circumstances: 

Upon responding to a complaint recently from a private citizen, local police
discovered boxes labeled as radioactive materials on the driveway of a 
private residence.  Subsequent investigation by NRC revealed that the boxes 
contained eleven used molybdenum-99/technetium-99m (Mo-99/Tc-99m) generators
manufactured by a major supplier of radiopharmaceuticals.  Four of the 
generators had intact lead shielding, and seven generators had no lead 
shielding.  The occupant of the residence was later identified as a 
subcontractor of the transporting company which has a contract with the 
major supplier to deliver new generators to, and pick up spent generators 
from, medical institutions.  According to this individual, these spent 
generators had been given to him for temporary storage, and he had removed 
lead shielding from some of them for sale. Apparently, many drivers 
routinely store spent generators at their residences for indefinite periods, 
and return them to the contractors of the transporting companies only when 
they are ready to pick up new generators for delivery.  NRC inspectors have 
encountered other situations where recovery of lead shielding from 
generators apparently had taken place. 

Average exposure rates measured on these generators were approximately 25 
mR/hr at contact and 2 mR/hr at 3 feet.  Based on information included on 
the generator labels, the generators were estimated to contain, at the 
maximum, a total of 43 millicuries of Mo-99 on the day of the investigation.  
Assuming that 5 mCi of Mo-99 remains on a generator column and that 10 
seconds are required to handle the column and to separate both internal and 
external layers of the lead shielding, a person could typically receive a 
dose of roughly 25 mrem to the hands from dismantling such a generator. 

Caution to Licensees - Users of Generators: 

You should note the following if you are involved in the receipt, 
possession, use, and transfer of these generators: 

1.   Your NRC license should contain specific procedures for disposing of 
     spent generators (e.g., return to supplier, etc.).  You are also 
     reminded of the letter dated June 4, 1981 from the NRC Material 
     Licensing Branch to all medical licensees.  As stated in this letter, 
     a condition authorizing decay-in-storage of certain radioactive 
     materials, including 

                                                          IN 81-32 
                                                          October 23, 1981 
                                                          Page 2 of 3 

     generators, would be automatically placed in new licenses issued, or 
     added to existing licenses in response to renewal requests.  You were 
     also informed in this letter that you have the option of submitting an 
     amendment request should you desire to add this condition to your 
     license immediately.  The proper way to store spent generators for 
     decay and subsequent disposal is to segregate the generator columns and 
     monitor them separately prior to disposal to ensure decay to background 
     levels.  Necessary precautions (e.g., use of disposable gloves) should 
     be taken to avoid hand contamination. 

     If the columns are held for decay to background levels, there are no 
     special requirements on disposal except for appropriate surveys to 
     verify total decay, records of the surveys, and defacing or removal of 
     labels on the devices.  Any surveys should include the lead shielding. 
     If no contamination is present on the shielding they may be disposed of
     as normal (non-radioactive) waste. 

     When storing spent generators for decay and disposal, you must comply 
     with the requirements of 10 CFR 20.105 (Permissible levels of radiation
     in unrestricted areas) and 10 CFR 20.207 (Storage and control of 
     licensed materials in unrestricted areas), and 10 CFR 20.203 (posting 
     and labeling requirements). 

2.   Until verification surveys determine that no radioactivity remains, 
     these spent generators must be treated as licensed material.  None of 
     the exemptions in Part 30 would apply.  Any person possessing these 
     items (for the purposes of lead recovery or waste disposal, for 
     instance) would be required to have an NRC license.  Any transfer to a 
     person without a license is an unauthorized transfer.  The only 
     exception would be the delivery of a properly packaged and labeled item
     to a common or contract carrier for expeditious transport to an 
     authorized recipient. 

3.   10 CFR 30.41 (b)(5) requires that licensed material be transferred only
     to a person who is generally or specifically licensed by NRC or one of 
     the Agreement States to receive the material.  You should ensure 
     that when transferring spent generators back to the supplier, the 
     common or contract carrier transporting the generators is fully aware 
     that any operations with or use of the material, other than the actual 
     transport or storage incident thereto, is not authorized.  Upon 
     delivery of the generators to the carrier for transport, you are urged 
     to provide specific instructions on the shipping papers, indicating 
     that the generators are to be delivered to the consignee without 
     unnecessary delay, are not to be stored in unauthorized locations, and 
     should not be dismantled or used by unauthorized persons.  As an 
     additional precaution, it would be judicious to establish a routine 
     point-of-contact with the supplier to inform him of the carriers being 
     used, and to ask for the supplier's cooperation in reporting to you any 
     apparent instances of improper actions, such as unauthorized lead 
     removal activities. 

Agreement States - Those States that have entered into an Agreement 
with the NRC to license and regulate nuclear materials, and facilities. 

                                                           IN 81-32 
                                                           October 23, 1981 
                                                           Page 3 of 3 

4.   The generator supplier may have provided instructions in the package 
     inserts regarding proper, safe and legal packaging and transport of 
     generators.  If you do not already have these instructions or are 
     unfamiliar with them, contact the supplier's representative 

5.   The instructions described in item 4 above may also apply to instances 
     during which defective generators need to be shipped back to the 

No written response to this information notice is required.  If you need 
additional information with regard to this matter, contact the appropriate 
NRC regional office. 

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