From the notice

The project consists of Maintenance Dredging within the North Side (Wharf N) of Reserve Basin and Schuylkill River Access Channel for the Government sites at the Philadelphia Navy Yard in the Public Works Department Pennsylvania area of responsibility. Maintenance dredging of approximately 96,611 cubic yards of sediment, using a sealed environmental clamshell bucket. Dredging within the Reserve Basin is in support of the Naval Support Activity Mechanicsburg, Philadelphia Navy Yard Annex. The Reserve Basin is being used to decommission various US Naval vessels. For the river pilots to be able to safely maneuver vessels through the Schuylkill River into the Reserve Basin berths and to ensure that tidal cycles will not cause sediment accumulation around the hulls making final removal very difficult, the berths need to be dredged to a minimum depth of -30 MLLW and a maximum over-dredge depth of -32 MLLW.