Investigation continues into last Friday's chlorine release at Michigan's Adventure Theme Park.

WOOD TV confirmed the Michigan Occupational Safety and Health Administration opened an investigation which could take weeks, or even months, to complete. Investigators are looking at human error as a possible cause of the release, which formed a cloud near the park’s wave pool Friday afternoon.

Muskegon County Emergency Services Director Sgt. Dan Stout II said park workers are assigned to monitor chemical levels at the pool. They feed their results into a computer, which adjusts the amount of chemicals in the water. However, there’s some indication the numbers fed into the computer were off, Stout said, which caused the computer to mix unsafe levels of two chemicals.

No serious injuries were reported in the incident, which White Lake Fire Authority Chief Gregory Holman called "a rare occurrence."