ALBUQUERQUE, N.M. (AP) — An incompatible combination of nitrate salts and organic cat litter is to blame for a mishap that forced the closure of the nation's only underground nuclear waste repository, according to findings released Thursday by an independent team of experts from national laboratories around the country. The technical team was charged by the U.S. Energy Department to investigate all the possible scenarios that could have led to the release of radioactive material at the Waste Isolation Pilot Plant in February 2014. The report comes more than a year after a single container of waste stored at the repository breached and contaminated 21 workers with low-level radioactivity. That container had been packed at Los Alamos National Laboratory. While it couldn't determine the cause of the breach with absolute certainty, the team said it was clear a thermal reaction inside the container forced the lid to pop. The contents — which included nitrate salt residues, the organic cat litter and a neutralizing agent — made for a "potentially reactive chemical mixture of fuels and oxidizers," the team said. The way the materials were situated inside the drum also likely played a role, it added. The salt residue comes from plutonium processing at the laboratory. The cat litter was used to absorb moisture in the waste. - Greg GuitarBuster

The technical team found that the radioactive contamination inside the underground repository came from the drum numbered 68660. WHERE DID THEY START NUMBERING!!! - Greg GuitarBuster