SALT LAKE CITY — Firefighters closed part of Redwood Road and California Ave. Tuesday evening after witnesses reported a cloud of unknown substance with an ammonia odor.
At about 9 p.m. 30 people at Sapp Brothers, a truck stop on Redwood Road, reported seeing a cloud and smelling ammonia. Hazmat crews were called to the area and saw a plume about three feet from the ground that quickly started to dissipate.
Hazmat’s air monitoring detected there was no toxic gases.
Firefighters checked with Thatcher Chemical and found the cloud came from a normal process of cleaning their air scrubbers. The process apparently releases water vapor that sometimes forms a cloud.
After determining there was no toxicity in the area, crews cleared the scene and opened the intersection to traffic.