This Auto-Doc implant removes any radiation taken from drinking an irradiated water source. It also appears to remove the radiation from some other beverages, but not all, nor does it always work on pools of water or puddles you may drink from.
The holotape can be found in Z-9 Crotalus DNA preservation lab on an operating table by the nightstalker tail, in the room at the end of the corridor. It is guarded there by Shadis, a unique night stalker.
This holotape contains an upgrade file for the Sink robotic assistant: "Auto-Doc".