In an attempt to correct what they thought was an out of trim condition, the non-nuclear construction team in the forward part of the boat purposefully defeated safety measures preventing accidentally filling ballast tanks while the sub was under construction. During construction, steel plates are welded over the ballast tanks flood ports to prevent water from getting into the tanks and putting the submarine in an unsafe condition. The construction crew put a fire hose down the tank's vent pipe and forced it past the check valve.