A fire at the El Dorado Chemical Co. in 2009 caused the evacuation of 70,000 residents due to the burning of ammonium nitrate, possibly causing minor respiratory problems. However, the city requested that only "anyone who can smell smoke or see smoke to evacuate their homes and businesses" and did not enforce an evacuation except for 500 homes in the nearby vicinity of the fire. Less than 1,000 residents chose to evacuate, taking shelter at Texas A&M University, which closed its campus for the day to ease traffic problems. City fire officials chose to let the fire burn down before tackling it, since the chemicals were water reactive. The evacuation, which started at 2:30 pm CST ended at 7 pm, except for a small, defined area immediately around the fire, where approximately 100 Bryan residents lived. In the end, only 500 residents were under a mandatory evacuation, and 35 people were treated for respiratory problems from the smoke. Officials from El Dorado said there was never any danger from the smoke or fire. The warehouse, valued at just under $1 million, was destroyed.