Corrective Action Unit (CAU) 563 is identified in the Federal Facility Agreement and Consent Order (FFACO) as âSeptic Systemsâ and consists of the following four Corrective Action Sites (CASs), located in Areas 3 and 12 of the Nevada Test Site: ¡ CAS 03-04-02, Area 3 Subdock Septic Tank ¡ CAS 03-59-05, Area 3 Subdock Cesspool ¡ CAS 12-59-01, Drilling/Welding Shop Septic Tanks ¡ CAS 12-60-01, Drilling/Welding Shop Outfalls Closure activities were conducted from September to November 2009 in accordance with the FFACO (1996, as amended February 2008) and the Corrective Action Plan for CAU 563. The corrective action alternatives included No Further Action and Clean Closure.