Deep Underground Command Center
The Deep Underground Command Center (DUCC) proposed by January 31, 1962, was to be excavated "3,000-4,000 feet down" with ~1.6 acres (0.65 ha) "located underground between the Mall and River entrances of the Pentagon" which are tbd feet above the mean Potomac waterline. Based on SAC's Deep Underground Support Center planned near the Cheyenne Mountain nuclear bunker, the DUCC plan was recommended to President Kennedy for fiscal year 1965 funding shortly before his assassination, but the underground DUCC, SAC's DUSC, and NORAD's SCCs were never built. (The 1953 Site R was "hardened further to about 140 psi blast resistance by 1963",:315 NORAD's Canadian bunker was completed in 1963, and NORAD's COC & SDC in the Colorado bunker became operational in 1966.)
- Ponturo, J. (June 1975). The Evolution of U.S. Strategic Command and Control and Warning: Part Three (1961-1967) (Report). Study S-467. Institute for Defense Analyses. pp. 267-370. "In February , the Secretary of Defense approved a National Military Command System (NMCS) composed of four major elements: the National Military Command Center (NMCC), an evolution of the JCS Joint War Room; the Alternate National Military Command Center (ANMCC), a redesignation of the JCS installation at the AJCC; and two mobile alternates, the NECPA and the NEACP.18 The following October he issued a DoD directive on the World-Wide Military Command and Control System (WWMCCS) that outlined the NMCS in detail, to include the NMCC, ANMCC, NECPA, NEACP, and such other alternates as might be established, together with their interconnecting communications; and defined their relationship to the command and control "subsystems" of the service headquarters, the CINCs, and other DoD agencies.19 … The fixed underground ANMCC would be phased out as superfluous, whichever version [50-man or 300-man DUCC] was chosen, and the other NMCS facilities would be cut back to some degree according to one or the other."
- Wainstein, L. (June 1975). The Evolution of U.S. Strategic Command and Control and Warning: Part One (1945-1953) (Report). Study S-467. Institute for Defense Analyses. pp. 1-138.