Enclave Oil Rig The Poseidon Energy Oil Rig ( named Control Station ENCLAVE in official Enclave records ) was a pre - War deep sea drilling platform , built over the world ' s last accessible underwater oil field in the Pacific Ocean , 175 miles off the coast of California . Background . The United States won the international race to establish a platform here in January 2073 , over the world ' s last known pockets of oil , after sabotaging Chinese efforts to do so . The oil deposit was originally thought to be unreachable , due to it being located thousands of feet below the seabed . During the nuclear storm of the Great War , the Enclave ' s most important members and essential personnel were evacuated to this location . It is logical to assume that this was no ordinary derrick , but rather , a disguised , powerful military base with heavy industrial facilities , top notch medical technology , completely self - sufficient , able to provide the Enclave with a highly efficient power base . During the course of " Fallout 2 " , the Chosen One must travel there via an oil tanker in order to save his tribe and the previous inhabitants of Vault 13 . The Enclave and President Richardson were preparing to release a form of the FEV into the world ' s jet streams , thereby preparing the Earth for re - colonization and killing everyone in the process . The Chosen One kills the President and destroys the Oil Rig by deactivating / destroying the coolant systems , overloading the primary reactor and causing a megaton - sized thermonuclear explosion . Both Marcus and the Remnants mention the rig in " " . Marcus was a part of the Chosen One ' s party during the raid to save the Arroyo villagers and Vault 13 dwellers , while the Remnants are unsure of how the rig met its end . Layout . The massive structure of the oil rig probably had many facilities for industrial manufacturing , research and development , Vertibird maintenance etc . However , in - game , only a small portion of the Oil Rig is visitable . Oil Rig Dock . The entrance to the rig , a large dock illuminated with yellow spotlights . Every arriving vessel docks here , and the PMV " Valdez " is no exception . Oil Rig Entry Hall . The entrance hall of the rig , lined with powerful auto - turrets that are designed to obliterate everything and everyone foolish enough to attempt an attack on the installation . The main hall ' s floor is a massive relief with the word Enclave stamped on it , with a small access terminal in the lower left corner . The hall connects via a spiral staircase to the detention / R & D level and the barracks , via a passageway with a waiting room . The final battle with Frank Horrigan is fought here . Oil Rig Barracks . Connected to the entrance hall , the Barracks area housed a storeroom , where T - 51b power armor s were used instead of forklifts , troop housing ( together with a large gym and lavatories ) , an armory stocked with explosives , the admin section for the soldiers and their CO ' s living quarters . A spiral staircase sealed behind flood doors connected to the Presidential level . Oil Rig Detention and Research Level . Houses the prison cells used to contain the Arroyo villager s and the people from Vault 13 . Also contains several small labs and medical facilities , and storage areas . It is located south from the entry hall , and connects to the trap room . Oil Rig Access Corridor . A series of small rooms with computer - controlled doors and an electrified floor . Unless the right combination of computers are accessed , the doors will trap the unfortunate explorer and leave them at the mercy of the floors . Two small side rooms provide storage and a reprieve from the traps . A GECK can be found here in the northeastern room in the left survival locker in the back Survival Gear room . It is south of the Detention Level and connects to the Presidential Level . Oil Rig Presidential Level . Home of the offices of President Dick Richardson , Vice - president Bird , Richardson ' s secretary , and the Enclave ' s other elite . Also contains a bomb , a war room , a conference room , and medical facilities where testing on the FEV is being done . A rear staircase connects it to the Reactor Level , and an emergency stairwell connects it to the Detention Level . Oil Rig Reactor Level . The deepest level of the rig , it houses the central computer , the rig ' s power generators , a small barracks , and several scientists and citizens to maintain the former two . It is only accessible by a staircase on the Presidential Level . Defenses . As a military base , the Oil Rig is heavily defended - Captain A . Ron Meyers refers to Poseidon guns that are able to blast even a tanker - size vessel out of the water if it doesn ' t have the Poseidon IFF protocol active . The actual number of vertibirds on the rig is unknown . Internally , apart from Enclave soldiers outfitted with regular and advanced power armor , an extensive network of security auto - cannons armed with heavy dual miniguns and sentry robots are present , ready to obliterate any foe . The Oil Rig is probably the single most well protected location in the entirety of post - nuclear America . Inhabitants . The Enclave Oil Rig was home to America ' s finest minds and people … in theory at least . In practice , years of isolation and propaganda have left the citizens of the Enclave decadent , xenophobic , and extremely dangerous to outsiders , in particular the soldiers . According to Dr . Curling , there were approximately 1000 inhabitants on the oil rig . Clearly identifiable were the " classes " . Citizens wore blue and yellow jumpsuits , identical in design to those of Vault - Tec shelter inhabitants , and carried no weaponry . Members of the science division wore lab coats and carried personal defense weapons ( usually a Wattz 1000 laser pistol ) , while the military ( including the Secret Service ) used T - 51b power armor and M72 Gauss rifles ( lower - ranking soldiers ) or advanced power armor and various heavy duty weapons . The President was unarmed , but carried what was probably the most important asset on the Oil Rig - the presidential access card , giving him full control over the systems of the drilling platform . Appearances . The Oil Rig appears at the very end of " Fallout 2 " and is mentioned by several characters in " " . It is also mentioned in Fallout 3 Official Game Guide and a terminal entry in the Boston Bugle building in " Fallout 4 " .