IAEA/SAL: PLUTONIUM "EXPLOSION" AT THE NUCLEAR LAB

C O N F I D E N T I A L UNVIE VIENNA 000448


IO/T, ISN/MNSA COCKERHAM, IO/UNP, ISN CTR CURRY; NA-243
GOOREVICH, LOCKWOOD, OEHLBERT, BRUNS; NA-241 SIEMON,
O'CONNOR, LAMONTAGNE; NRC FOR OIP - DUNN LEE, HENDERSON,
SCHWARTZMAN; USDOC PASS NIST FOR DAVE SIMONS; AFTAC FOR
CHARLES BRENNAN

E.O. 12958: DECL: 08/08/2033
TAGS: AORC KNNP IAEA ENRG TRGY
SUBJECT: IAEA/SAL: PLUTONIUM "EXPLOSION" AT THE NUCLEAR LAB

Classified By: AMBASSADOR GREGORY L. SCHULTE FOR 1.4 REASONS B AND D


1. (C) Summary. A contamination incident occurred at the
IAEA's Safeguards Analytic Laboratory in Seibersdorf on
August 3, in which five plutonium reference solution vials
exploded due to a buildup of gases, primarily hydrogen. The
vials, which were 15 years old, built up gases to an
estimated 14 atmospheres of pressure as the plutonium
solution decayed. SAL officials suspect that a small
electrostatic discharge likely instigated the explosion in
one vial, setting off the rest. A small portion of the lab
remains closed off and sampling efforts continue to ensure
all contamination is contained, particularly to ensure the
Clean Laboratory at Seibersdorf is not contaminated.
Operations at the laboratory continue uninterrupted for the
time being, although we expect delays in the near future as
the room of the incident is closed and unable to receive
nuclear samples. Contrary to news reports, the incident was
not caused by "aging infrastructure," although the
Secretariat indicates that the poor layout of the nuclear
laboratory will magnify the risks of cross-contamination.
End Summary.


2. (C) On August 3 at 2:30 AM, a continuous air monitoring
(CAM) alarm was set off at the Nuclear Material Laboratory in
Seibersdorf. This laboratory is part of the Safeguards
Analytic Laboratories. The alarm was located on the ground
floor in the "Plutonium Stores Room," which holds plutonium
reference materials and high-activity waste that is staged
for disposal. This multi-purpose room also receives nuclear
samples, not by design but by lack of space in the nuclear
material laboratory. Shortly after the first alarm, four
additional CAM alarms went off in the Plutonium Laboratory on
the second floor.


3. (C) Emergency responders arrived on site shortly after
the alarm, including health physicists, to evaluate the
situation. The Plutonium Stores room houses three shielded
safes that hold the radioactive material. The responders
opened Safe #3 first, as this was the last safe accessed on
Friday, August 1. Steel drawers were deformed, showing
evidence of an explosion. The responders took photographs of
the area and quickly shut the safe to control the spread of
contamination. The safe remains unopened as of August 3.


4. (C) Using the photographs, SAL officials have been able
to reconstruct the events on Sunday morning. The explosion
resulted from five plutonium solution standards that were
contained in sealed glass vials. The 50 milliliter (mL)
capacity vials contained 20 mL of nitric acid (1.5 molar
concentration) solution with 8 mg/mL of plutonium-240 that
was 99-percent pure. The samples were 15 years old as they
were prepared in 1993 in Russia for SAL. SAL received the
samples in 1997. The glass vials were wrapped in two layers
of heavy duty plastic. (Note: Plutonium-240 is an unstable
isotope (alpha-emitter) with a short half-life.) According
to SAL officials, gases built up over the years inside the
vials, primarily hydrogen. Based on their estimates, the
pressure built up by the decaying Pu-240 was approximately 14
atmospheres, releasing about 3.5 kilojoules (kJ) of energy.
One SAL official noted that a small electrostatic discharge
likely instigated the explosion in one vial, setting off the
other vials given the intense pressure.


5. (C) The four additional CAM alarms that went off were
located in the Plutonium Laboratory on the second floor. CAM
filters on the second floor picked up contamination at lower
activity levels than the CAM filter in the Plutonium Stores
room on the first floor, however, no further contamination
was found in the second floor laboratory. The incident in
the Plutonium Stores room exposed a vulnerability to the
Nuclear Material Lab, that the sinks in both rooms shared a
common drain that is now unused. No other rooms in the
Nuclear Material Lab picked up any contamination, although
the IAEA continues its evaluation of swipes in the laboratory.


6. (C) SAL is taking steps to ensure there is no
cross-contamination of nuclear material in other rooms in the
nuclear lab, with the primary concern being contamination
reaching the SAL's Clean Laboratory in Seibersdorf. Another
concern is contamination to the environment. The filter on
the ventilation system for the building did not show signs of
contamination, which is a positive sign that contamination
did not make it outside the building. The IAEA continues to
take environmental samples of the surrounding area. While
the incident did not result from "aging infrastructure" as
reported in the news, the cross-contamination concerns are
magnified by the poor layout of the Nuclear Materials Lab,
resulting from space restrictions. SAL awaits bio-assay
results to ensure personnel are not contaminated.


7. (C) Operations at the Nuclear Materials Laboratory
continue uninterrupted although delays in operation will
almost certainly occur as the Stores room is unable to
receive samples. In the meantime, the IAEA is working with
the Austrian Ministry to approve another room for receiving
samples. In addition, SAL is not able to stage high-activity
waste or retrieve samples from the Stores room.


8. (C) IAEA informed its sister-laboratories in the Network
of Analytic Laboratories (NWAL) about the incident on August
7 to provide a lesson-learned and warn of the potential risk.
The IAEA expects it will need outside help in the near
future for containment and clean-up of the contamination.
According to a senior SAL official, a Canadian company has
already offered its services to the Director General,
although the official said that Los Alamos National
Laboratory may have some of the needed radiolysis expertise.


9. (C) Comment: UNVIE will continue to monitor the
investigation of this event to determine if safety issues are
being adequately reviewed and addressed.


SCHULTE