Vault 42 is a large, semi-subterranean construction by Vault-Tec as a part of Project Safehouse in the California wastes built around 2073, both near and beneath the nearby town of Swallow Hills, before being occupied on the eve of the Great War. The Vault survived the Great War, but was nearly destroyed by an intentional defect that the construction crew and Vault-Tec had implemented as a part of Project Safehouse's unethical Societal Preservation Program when it's nuclear core nearly detonated. Though the catastrophic possibility of a nuclear blast was avoided by the quick actions of a few brave souls, the radiation leaked into most of the Vault and forced the majority of the residents to evacuate to safer areas within the vault, away from the now heavily irradiated reactor room and surr