"Lockheed Martin staff at the Santa Cruz, Calif., Facility conducts
a full system test of the Post Boost Control System. This system,
which consists of two pairs of solid-propellant gas generators and
four integrated valve assemblies, maneuvers the U.S. Navy’s Trident
II D5 Fleet Ballistic Missile following the separation of all three
boost-motor stages"
"Lockheed Martin staff at the Santa Cruz, Calif., Facility conducts
a full system test of the Post Boost Control System. This system,
which consists of two pairs of solid-propellant gas generators and
four integrated valve assemblies, maneuvers the U.S. Navy’s Trident
II D5 Fleet Ballistic Missile following the separation of all three
boost-motor stages"
http://www.lockheedmartin.com/content/dam/lockheed/data/space/documents/tridentdiid5/SantaCruzFacility%20Brochure.pdf