An “improperly abandoned” Puget Sound Energy (PSE) gas pipeline was the cause of an explosion in Greenwood that leveled two buildings and damaged nearly three dozen businesses in March 2016, a new report finds. PSE could be subject to up to $3.2 million in penalties. The Washington Utilities And Transportation Commission released the report Tuesday. Investigators concluded that human activity was likely the immediate cause of the gas leak — but that the leak would not have occurred had the utility company PSE followed safety regulations when they abandoned the pipe in 2004.