The U.S. Chemical Safety and Hazard Investigation Board said a team of investigators would arrive at the paper mill Wednesday. The implosion involved white liquor, a highly corrosive chemical used in paper and pulp processing to dissolve wood chips into pulp. Officials said a 900,000-gallon tank storing the substance ruptured with 90,000 gallons of the chemical still inside. Previously, officials said the tank held only 80,000 gallons. This story continues below. “The CSB is opening an investigation into this tragic incident to determine how it happened and what can be done to prevent something like this from…