A government report released this week blasted the safety procedures for handling radioactive waste at the Los Alamos National Laboratory in New Mexico, following a leak that prompted a shutdown in February.

The inspector general of the Department of Energy said a barrel of plutonium-tainted debris was improperly packaged, then shipped to the Waste Isolation Pilot Plant in Carlsbad, N.M.in February to be stored in an underground storage facility a half-mile beneath the surface. Once at WIPP, a salt truck caught on fire underground, causing a chemical reaction inside a waste drum that released trace amounts of americium and plutonium. Some 22 plant employees were contaminated, forcing a shutdown of the facility that is still in effect.

According to the DOE, operations at WIPP were suspended and the nation's only operating deep geologic repository for the permanent disposal of defense-related radioactive waste was shut down for an indefinite period. The shutdown has already cost taxpayers tens of millions of dollars. The DOE projects a 2016 re-opening of the plant.

Among the critical points made in the report, the DOE accused the laboratory of permitting the introduction of potentially incompatible materials in waste drums to be stored at WIPP, and a failure of the lab's safety procedures to prevent this from occurring.

"Our review identified several major deficiencies in LANL's procedures for the development and approval of waste packaging and remediation techniques that may have contributed to the radiological event," said the report.  "Of particular concern, not all waste management procedures at LANL were properly vetted through the established procedure revision process nor did they conform to established environmental requirements."

There was also concern about how the lab was disposing of volatile mixtures of nitrate salts and organic matter which a 2000 U.S. Environmental Protection Agency report found to be "inherently hazardous."

The government auditor said the lab should have included an inorganic absorbent material such as kitty litter in the nitrate salt mixture, but that it used organic material instead, ignoring a 2012 report suggesting the more effective and safer method.

The Inspector General report is consistent with many of the waste processing issues already recognized by the Department and the lab, and the Department has already initiated actions to address the underlying issues identified in the report. 

Laboratory spokesman Matthew Nerzig declined to comment on why safety policies were violated.

FoxNews.com's Joseph J. Kolb contributed to this report