All vaults were originally supposed to be equipped with one. The GECK is apparently the size of a suitcase and able to be mass produced. Project Purity suceeded in DC, apparently by way of the GECK (garden of eden creation kit (results may vary)). The Institute guy you killed in Fallout 3 to save the runaway courser (and get his weapon). You know it's the same time frame after talking to the acting head of Synth Retention in the Institute and finding out whose place he took. The aim of Purity is to make ALL the water in the region nonradioactive. This adventure takes place at about the same time as James is perfecting Project Purity in DC. One reason I have no problem with the Aqua boy/girl perk is that it shouldn't be needed anyway.
