A Medevac helicopter lands at a triage center set up on highway LA 3115 near the Williams Olefins chemical plant, after an explosion and fire there, in Geismar, Louisiana June 13, 2013. An explosion and fire tore through the chemical plant in Geismar, Louisiana, on Thursday, injuring 33 people and leading authorities to order people within two miles (3 km) to remain indoors. REUTERS/Jonathan Bachman ( US-CHEMICALS/FIRE )