In the winter of 1993, a white liquor clarifier tank exploded at an Oregon paper mill. Two pipe fitters lay dead. …Nearly two decades later, in 2012, four workers were injured by the same chemical compound on the opposite side of the country. …And when an estimated 900,000 gallons of white liquor spilled from a ruptured tank at the Nippon Dynawave paper mill in Longview on May 26, it was those same alkaline chemicals that contributed to the death of 11 workers. Investigators have yet to determine the root cause of the deadliest industrial accident in recent Washington history. But the grave hazards have long been known, yet white liquor remains minimally regulated. Few laws directly govern the papermaking substance. …There is little mention of white liquor in state or federal environmental regulations or worker safety laws. Instead, it is largely up to the companies to ensure its safe handling. [to access the full story a Seattle Times subscription is required]