A 55 gallon drum of chemicals spilled Monday around noon at the Tesla Gigafactory, prompting an evacuation.  Storey County Emergency Manager Joe Curtis says the chemical spilled was a cleaning agent, and the incident occurred in what’s know as a “clean room.” That means that the HVAC system would have kept the chemical inside just that room.  In fact, work continued inside the plant following the incident while the spill was cleaned up. One person was taken to the hospital, and a number of others were treated at the scene.