Operation: WHITE GLOVE
Operation: WHITE GLOVE was the code name for the contingency plans to destroy the Office of Naval Intelligence's CASTLE and Sword Bases. In the event that one of the facilities was ever in danger of compromise by the Covenant, a single person was to remain behind and enact the operation, detonating the explosives planted within the facility in order to destroy the base and prevent its secrets from being captured by the Covenant.
The operation also called for the destruction of every artificial intelligence in the facility using the fail-safe in its Riemann matrix before the base was destroyed, thus ensuring that the Covenant did not capture such technology.
On August 23, 2552, during the Fall of Reach, SPARTAN Noble Team was tasked with destroying Sword Base in accordance with Operation: WHITE GLOVE. By August 29, Sword Base had been captured by the Covenant. Dr. Catherine Halsey remained in a complex of Forerunner ruins located one and a half kilometers east of the base and two thousand feet underground. Carter-A259, the leader of Noble Team, insisted that Sword Base must be destroyed, though Halsey countered that others would perform the demolition. As Halsey was escorted to CASTLE Base by Jun-A266, she detonated a series of explosive charges, burying the ruins to prevent their compromise by the Covenant. However, it is unknown whether this also destroyed Sword Base or if the base was destroyed later, as Halsey had suggested. Dr. Halsey's personal journal was secured by the Office of Naval Intelligence before the base's demolition.
By August 30, Halsey had arrived at CASTLE Base. Although the rest of the facility's personnel had evacuated, she remained behind to enact Operation: WHITE GLOVE. She was accompanied by the AI Kalmiya, a predecessor of Cortana, and was harried by Araqiel, the personal AI of her nemesis, Colonel James Ackerson. After erasing Araqiel with a fail-safe command, Halsey did the same to Kalmiya. When the surviving SPARTAN-IIs of Red Team arrived at the facility, Halsey destroyed the facility via the self-destruct charges installed throughout the base. She, Frederic-104, William-043, Vinh-030, Isaac-039, and Kelly-087 were able to hide in the caves beneath the base. They were able to stop the Covenant from accessing the slipspace-distorting crystal in the Forerunner complex beneath the base, though they became trapped under the base for several days.