Event Notification Report for November 13, 2006

LEAKING SR 90 SOURCE

In the process of conducting the semiannual leak tests for sealed sources, a leaking Sr- 90 source was discovered on 11/13/2006. The Sr-90 source is used by the Physics Department in Room 365 of Jadwin Hall. The Sr-90 source has an activity of 180 microcuries and is normally stored in Room 361 of Jadwin Hall. The source actually consists of a foil on which Sr-90 has been electroplated. The foil is situated in a brass cylinder that consists of two cylindrical pieces - the piece in which the foil sits and a collimator end that is usually screwed onto the end containing the foil. When the leak test was conducted 6 months ago, there was no leakage. But after discovering contamination during the leak test on 11/13/06, it was found that a small hole has been punched through the foil so that the foil's integrity is compromised. The last time the source was used was approximately 6 weeks ago, so the damage occurred sometime between May and the end of September. Contamination (less than 150 dpm) has been found on spots on the floor in Room 361 of Jadwin Hall where the source is usually stored. Contamination has been found on a variety of surfaces on which the brass cylinder was set. A very rough estimate of the amount of missing activity is believed to be approximately 25% of the original activity.

No contamination has been found in public spaces. Surveys have been conducted for the two hallways that border the labs in which the source is used (Room 365) and stored (Room 361). Surveys have been conducted in the office of the sole research staff member who uses the source, and the lab in which the source is stored (Room 361). Results from the survey of the hallways and the office show no contamination problem exists in those areas. The wipes from the lab surveyed on 11/14/06 will be available on 11/15/06, but the G-M survey reveals no gross activity other than in the cabinet in which the source is stored and on the floor directly in front of the cabinet. Those areas were readily decontaminated.

On 11/15/06, surveys will be conducted in the lab in which the source is actually used (Room 365). Preliminary surveys on 11/14/06 indicated a number of surfaces that are contaminated in that room, and more thorough surveys will be conducted. All suspect areas have been locked and posted. No personal contamination has been discovered. The person who used the source is out of the area and will provided a urine sample when they return.

The licensee expects that decontamination will be complete by 11/16/06 and the rooms will have access restored.

Licensee has notified NRC R1 (Modes).

MISSING SOURCES

While licensee was conducting their semi-annual inventory of sources they discovered that two sources were unable to be located. One source, 13.9 milliCuries of Ni-63, was believed to be a double entry in the inventory log, however, that is not confirmed at this point. A second source, 10.4 microCuries of Am-241, is also missing. The RSO has been notified. The licensee is continuing to search for the missing sources. A meeting was held by the licensee to review their inventory control procedures and see how this can be prevented in the future.



THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL

Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks.

AGREEMENT STATE REPORT - LOST PO-210 SOURCE

A 0.5 milliCurie Po-210 static eliminator source was lost by 3M Corporation. 3M was performing an inventory and determined the source to be missing on 11/13/2006. The state will follow up with additional details when supplied by the licensee.

* * * UPDATE PROVIDED VIA FAX BY CRAIG VERKE TO JEFF ROTTON AT 1341 EST ON 12/12/06 * * *

The State provided the following information via facsimile:

" The lost device is a model P2042 Nucleospot nuclear static eliminator, manufactured by NRD Inc. The original activity of the source was five millicuries of Polonium-210 at the time of its manufacture in September of 2005. The current, decayed activity of the source is 0.5 millicuries. The static eliminators are leased by NRD for a one year period and returned to NRD at the expiration of the lease.

"3M uses about 40 of these devices in weighing balances in research laboratories at 3M Center, St. Paul MN. Receipt, shipment and annual change outs of the devices at the end of their lease is handled by a member of Corporate Health Physics (CHP). An individual in the laboratory where the device is used is designated as the Radiation Safety Officer (RSO) and is responsible for day-to-day use of the device. The RSOs conducts semiannual physical inventories of their devices, most recently in July 2006.

"The device in question was in use in a laboratory of the 3M Pharmaceutical Division in Building 260 on 3M Center. It was not in the balance where it was normally used when CHP attempted to replace it at the end of the lease in November 2006. It was then learned that the RSO for the laboratory had taken a different position at 3M and had not been in the laboratory since the physical inventory in July.

" CHP was not notified of the job transfer by the laboratory RSO. Therefore, there was a period of several months when there was no individual specifically responsible for the device. During that time we believe the device was moved to a different 3M laboratory for use there and placed in a drawer or other storage location by an employee who has since left the company. Since 3M announced plans for the sale of the Pharmaceutical Division, many research employees in that division have taken positions with other companies. The device may have been disposed of in the trash, though this seems unlikely as it has a radioactive material label. It also appears likely that it was stolen as it has no intrinsic value and little usefulness outside of a laboratory.

" Radiation exposure would not result from this device in an unrestricted area. The emitted alpha radiation is completely shielded by clothing or the dead skin layer on the outside of the body. The radioactive material is sealed in a capsule, which is further enclosed in the body of the device itself, thus preventing inhalation or ingestion. Wipe tests performed by 3M in January and July, 2006 showed no contamination at a minimum detection level of 1 x 10-6 microcuries.

" Actions taken to recover the lost device involved interviews with personnel in the laboratory where it was used and searches of that and surrounding laboratories. Emails were sent to persons working in the laboratories asking them to provide any information they had on the location of the device. Flyers with pictures of the device requesting its return were posted in the laboratories.

" Measures to ensure against a recurrence are:

- Reminders to laboratory RSOs and their management to notify Clip of any change in location of a nuclear static eliminator or in the job status of the RSO.

- Reminders were given to those working in the laboratories, during the course of the searches, of the need to leave the nuclear static eliminators in their assigned location."

Notified NMSS EO (Morell), R3DO (Lara), and ILTAB (via email).


THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL

Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks.