On April 10th of this year, more than a dozen people were taken to the hospital after being exposed to a chemical known as tetrachloride. The spill happened around 3 p.m. in a science lab basement on the Colorado College downtown campus. 12 of 13 patients were released after being treated by paramedics. A CC employee remains hospitalized as a precaution. The incident caused Olin Hall and the Barnes Science Center to be shut down for several hours.