History of a leak

June 2011: Las Conchas Fire threatens transuranic nuclear waste stored at Los Alamos.

Jan. 5, 2012: New Mexico Environment Department and Los Alamos National Laboratory prioritize cleanup of above-ground legacy waste and agree on a June 30, 2014, deadline to ship all Cold War-era nuclear waste to the Waste Isolation Pilot Plant.

June 26, 2012: Gov. Susana Martinez visits Los Alamos to celebrate the 1,000th shipment of waste to WIPP.

Aug. 1, 2012: LANL changes policy, requiring organic kitty litter instead of the clay-based variety to absorb liquids in packaging of nuclear waste.

September 2012: The lab begins using organic kitty litter exclusively as an absorbent in waste.

August 2013: LANL officials authorize waste packaging contractor EnergySolutions to add neutralizer to acidic waste, despite manufacturer’s warnings about incompatibility.

Dec. 4, 2013: Waste Drum 68660 is packaged at Los Alamos for shipment to WIPP.

Feb. 5, 2014: An underground truck fire forces evacuation at WIPP.

Feb. 14, 2014: A chemical reaction causes the drum to rupture, triggering a radiation leak that exposed more than 20 workers to contamination and indefinitely shut down WIPP.

May 2014: The first public reports emerge that organic kitty litter may have been a factor in the radiation leak at WIPP, and WIPP officials learn details about the waste from LANL that indicate the lab hid certain truths about its contents and their volatility.

June 17, 2014: LANL scientists conclude heat from the ruptured drum at WIPP could have made up to 55 more drums stored nearby more volatile.

July 23, 2014: LANL officials acknowledge a lead-contaminated glove in the waste drum that burst at WIPP has been added to the factors being investigated as the possible cause.

Sept. 30, 2014: U.S. Department of Energy announces full resumption of activities at WIPP could be five years away and estimates the recovery cost at $500 million.

Oct. 1, 2014: U.S. Department of Energy Office of Inspector General issues a report condemning LANL for failing to follow its own internal safety procedures and warnings against mixing volatile components in the drum that ruptured at WIPP.