The Andover city water supply is in no danger after a contractor mistakenly mixed the wrong chemicals together, according to a city official.
David Berkowitz, Andover’s public works superintendent, said a contractor put a fluoride chemical into a tank that contained sodium hypochlorite, which caused a chemical reaction.
The presence of hazardous fumes meant the building had to be evacuated and no personnel will be working in there until air quality tests deem it safe, according to Andover Fire Chief Dan Winkel.
Berkowitz said the city’s water supply was not affected because the water tower was full, so the pumps were not operating and water was not being treated when the accident happened.
He said the tank with the bad mixture was drained. There is another tank of sodium hypochlorite so water can still be treated. In addition, the water treatment plant can run remotely until air tests determine it is safe for humans to enter the building.
Winkel said the fire department received the call about 11:45 a.m. Monday that there had been a chemical reaction at the water treatment plant. Firefighters entered the building with breathing apparatus. No chemical suits were needed.
As of Tuesday afternoon, the doors for the water treatment plant were open and fans were running to ventilate the building.
The Andover/YMCA Community Center, Andover Elementary School, Andover City Hall and Sunshine Park are nearby public facilities. There are also a lot of homes and businesses near this civic center of Andover.
Winkel said nobody had to be evacuated from the surrounding areas. The evacuation was limited to the water treatment plant.
According to Winkel, the Minnesota Department of Health visited the site and approves of the steps the responders are taking to correct the problems.
The case remains under investigation.