MIAMI — Investigators with the National Institute of Standards and Technology issued a preliminary summary of their findings Thursday regarding the catastrophic collapse of Champlain Tower South, stating the pool deck had “critically low margins against failure.” According to the summary, the pool deck was severely underdesigned in the portion of the deck that collapsed seven minutes before the rest of the tower fell, killing 98 people in the early hours of June 24, 2021. At a public hearing Thursday, investigators noted the problems that began with pervasive weaknesses in the structural desig...