(UPDATE 5/20/2014) Possible culprit: kitty litter. See my new post.
And it was a container from Los Alamos National Laboratory (LANL).
The first report of radiation leak (plutonium) from the Waste Isolation Pilot Plant (WIPP) that necessitated the evacuation of workers and plant shutdown was in February this year.
From Department of Energy WIPP Update (5/16/2014):
New Information Provided About Possible Contributor to the WIPP Radiological Event
The Department of Energy issued the following statement today regarding new information generated during the May 15 entry into WIPP:
Since the February 14 radiological release, the Department and its Waste Isolation Pilot Plant have been working deliberately to safely determine the cause of the release. The team that entered the underground facility yesterday was able to get additional visual evidence that shows a damaged waste container, identified as one from Los Alamos National Laboratory.
In the new pictures, the LANL container has a cracked lid and shows evidence of heat damage. Workers will continue investigating to determine what caused the container breach and if any other containers were involved or damaged,” said a DOE spokesperson.
Community Meetings Scheduled
May 20 – A WIPP Recovery update will be provided at the Economic Development Corporation of Lea County Annual Meeting. The update, which will be provided by a member of the NWP Communications team, is scheduled for 11:30 a.m. Location: Hobbs Country Club, 5001 W. Carlsbad Highway.
May 22– The City of Carlsbad and DOE will co-host its weekly meeting featuring updates on WIPP recovery activities. The meeting is scheduled today at 5:30 p.m. Location: Carlsbad City Council Chambers, 101 N. Halagueno Street. Live streaming of the weekly meetings can be seen at http://new.livestream.com/rrv/.
"Evidence of Damaged Drum in Panel 7, Room 7" from DOE WIPP "Photo and Video" section (more photos at the link):
"The May 15 entry into Panel 7, Room 7 produced this photo of a waste container (left) with its lid unsealed and apparent heat discoloration."