As millions of gallons of chemical-laden wastewater gushed into Colorado’s Animas River in August, the Environmental Protection Agency called the disaster “likely inevitable.” Not so, say federal investigators in a new report that blames the EPA for the blowout.

The Department of Interior found that “an EPA cleanup crew rushed its work and failed to consider the complex engineering involved, triggering the very blowout it hoped to avoid,” the Associated Press reports.

Though the EPA knew of the risk of a blowout as early as 2014, its crew failed to consider water levels before it began its remediation work at Gold King Mine, an abandoned site in La Plata County.

The AP continues:

Instead, the EPA crew, with the agreement of Colorado mining officials, assumed the shaft was only partially inundated.

"This error resulted in development of a plan to open the mine in a manner that appeared to guard against blowout, but instead led directly to the failure," according to engineers from Interior's Bureau of Reclamation, who spent two months evaluating the technical circumstances.

The blowout fouled rivers in Colorado, Utah and New Mexico, temporarily shutting down drinking water supplies and cropland irrigation.

… A U.S. Army Corps of Engineers official whose review of the conclusions was included in the report expressed "serious reservations" over the EPA's failure to explain exactly how its communications broke down and why its officials were so insistent on starting work without more information about the complexities involved.

Richard Olsen, a senior geotechnical engineer with the Corps, also questioned why a change in the EPA field coordinator for Gold King led to an "urgency to start digging" even though another EPA official had expressed some uncertainty about the potential risks.

As the AP notes, the federal report didn’t list the names of individuals responsible for botching this cleanup effort.

Heads should role—but then again, this is the federal government, where even egregious misconduct can result in bonuses, not firings. Nevertheless, the new report highlights the incompetence and irresponsibility of an agency that holds the private sector to uncompromising standards.

More scrutiny on the EPA’s error and response will follow soon, with the EPA inspector general conducting his own investigation. Such examination is certainly merited, especially given these new revelations that the EPA lied about its responsibility for the environmental disaster.