Inver Grove Heights fire chief Judy Thill confirmed Monday afternoon that a "small drip" of anhydrous ammonia was coming from a leaky tank inside Pomp's Tire Services.
Pomp's is located at 3134 117th Street East, which is adjacent to the Flint Hills Resources Minnesota headquarters building and within a half mile from the Pine Bend refinery.
Anhydrous ammonia is a colorless, highly irritating gas with a sharp, suffocating odor.
Chief Thill also confirmed that—apart from a sour smell—there was never a danger to the public during Monday's incident. She speculated that the drip was coming from a leaky valve or extra pressure built up inside the tank.
IGH FD will continue investigating the cause of the leak.
"This is an extremely minor situation," Chief Thill told Patch. "We're just here to mitigate the leak as much as possible before we leave."
According to the University of North Dakota health department, immediate effects of exposure to anhydrous ammonia include:
Burning of the eyes, nose, and throat after breathing even small amounts. With higher doses, coughing or choking may occur. Exposure to high levels of anhydrous ammonia can cause death from a swollen throat or from chemical burns to the lungs.
Eye exposure to concentrated gas or liquid can cause serious corneal burns or blindness. Generally, the severity of symptoms depends on the degree of exposure.
Despite the presence of the Dakota County Special Operations Team (DCSOT) at the scene, no injuries or individuals with symptoms were reported.
According to its website, the DCSOT specializes in incidents involving hazardous materials, weapons of mass destruction, technical rope rescue, confined space rescue and trench rescue.
Inver Grove Heights Patch will continue to update this story as more information becomes available.