US Ecology has indicated that a customer failed to provide it with necessary information about waste that caused an explosion that killed one worker and injured eight others while being processed at the company’s its Grand View, Idaho, facility.
In an executive summary to the report on the company’s investigation of the Nov. 17, 2018, incident, US Ecology said the explosion occurred as workers processed the first tranche of 193 drums of magnesium waste shipped from an unidentified New Jersey company.
The contents of 43 drums of ultra-fine magnesium powder were placed in a treatment pit at the Indoor Stabilization Building at Grand View. The material was then mixed with water using an excavator, which was standard protocol, the report says.
“Upon initiating the mixing process with the excavator, a catastrophic explosion occurred that caused extensive building damage, and resulted in the death of the excavator operator,” according to the summary. “Two other employees who were adjacent to the Indoor Stabilization building also suffered direct injuries.”
The water hitting an abnormally hot segment of material— more than 100 degrees Celsius — caused a steam explosion, according to US Ecology summary. The heated area was the result of a chemical reaction involving the magnesium, water, and other materials that had not been listed in paperwork sent by the waste generator, the document says.
“There were several other metals and constituents (including iron and zinc) in the waste that weren’t expected to be present that impacted how the waste behaved during treatment,” US Ecology spokesman Dave Crumrine said by email Monday.
The explosion would not have been likely had the water come into contact only with pure magnesium powder, US Ecology said the summary.
US Ecology’s conclusion largely mirrors the findings of the U.S. Occupational Safety and Health Administration, although the two probes differ in details. For example: OSHA said the mixing of water and magnesium released hydrogen and oxygen, with the hydrogen igniting. US Ecology is contesting a proposed $66,300 fine by the federal agency.
