PORTLAND, Ore. (AP) -- The accidental mixture of an acid and a caustic liquid at an Oregon dairy processor tank has sickened 11 people.
Portland Fire & Rescue spokesman Paul Corah says none of the 11 people's respiratory symptoms was believed to be life-threatening.
The chemicals were mixed at a tank at West Farm Foods. Firefighters evacuated the plant of its workers Wednesday morning.
Crews were working late Wednesday to keep the tank from overheating.
The reaction was set off when 450 gallons of acid were accidentally offloaded from a truck into 1,150 gallons of the caustic liquid.
The chemical reaction heated the tank and the temperature reached 120 degrees. Technicians say the tank could melt and the combined liquids could leak into the ground if the temperature reaches 150 degrees.