BALTIMORE — A fiery explosion in March at the Baltimore City owned Back River Waste Water Treatment Plant has been deemed accidental.
The Baltimore City Fire Department recently released an investigative report into the incident.
It determined the explosion began inside a dryer used to convert sewage sludge into pellets for agricultural use.
Dust inside the dryer was found to be the original source of ignition which led to the combustion of thermal oil.
RELATED: Fiery Explosion reported at Back River Waste Water Treatment Plant in Dundalk
The part of the facility where the explosion occurred is run by Synagro Technologies, a private third-party biosolids treatment company.
According to investigators employees tried extinguishing the fire before 911 was called.
It was previously reported that seven people were inside the building at the time. None were injured.
Investigators estimate the total damage to be around $20 million.
Following the incident Maryland's Department of Environment issued a progress report suggesting drying operations had been slowing prior to the explosion.
"Normally the Synagro Facility was processing 55-58 dry tons/day. However, during the month before the explosion it was down to about 40 - 45 dry tons/day." the report stated.
After the fire all operations were suspended for a prolonged period.
The fire was just the latest setback at the waste water plant.
Last summer the state took over operations after the plant repeatedly discharged sewage raising environmental concerns.
Although improvements have been made, the state remains on site.
The State says it wants the plant to comply with certian permit limits for three consecutive months.
