United States Chemical Corps

The U.S. Chemical Corps is a division of the Enclave in 2241.

Background
The Enclave did not return to the mainland for decades and did not interfere with continental affairs. It was not until c.2140 that the organization became aware of survivors on the mainland. It is not known what caused this decision, but it was in this time that the Enclave adopted a policy deeming it the sole remaining bastion of "pure," mutation-free humanity on Earth. Cohabitation with wastelanders was deemed untenable, leading to the decision to pursue extermination of "mutants."

It was 2236 that brought a breakthrough in the activities of the chemical corps, responsible for developing the means to carry out Enclave's genocide. On July 20th, 2236, Enclave scouts (re)discovered the ruins of the Mariposa Military Base. The group scoured the base, while assault squads began gathering slaves to use for excavating the base. Excavation began in September. The slaves and construction crews dug into the collapsed base, removing tons of rock. Unprotected wastelanders were exposed to low levels of FEV in the ruins, released after the base self destructed and mutations began to occur. At the same time, Frank Horrigan was exposed to the virus and sent to the oil rig for study. The excavations were completed in January 2237. Shortly after Enclave scientists managed to obtain a pure sample of FEV and leave the base, the mutants rose up against their Enclave overseers. After suffering heavy casualties, the Enclave forces fell back and sealed the mutants in the ruins of the facility.

Although it came at a heavy price, the sample allowed the Enclave to finally start research into the creation of a biological agent that would allow for killing mutants worldwide. Dubbed FEV Curling-13, after Lt. Col. Charles Curling, the leader of the project, the sample was modified and refined by the chemical corps. The Enclave defined the project's goal as achieving a global clean sweep with a 99.5% extermination rate. In the meantime, between 2236 and 2238, the scientists experimented on Frank Horrigan. The mutating trooper was kept heavily sedated: whenever he was conscious, "incidents" occured that result in major bloodshed. By January 2239, tests ran dry and the decision was made to use Horrigan for field work. On March 27, 2239, Horrigan was sealed within power armor custom-manufactured to fit his massive physique. After a number of horrifically successful field tests, he became the Enclave's solution to a number of sticky problems.

In 2241, the project was in its final stages. Although the Enclave ran into shortages of certain critical chemicals, they got around that problem by forming a secret relationship with the Salvatores of New Reno: In exchange for laser pistols, the mobsters provided them with the necessary chemicals made in their drug labs. Final testing required representative population samples for the toxin and the inoculation against it. The Enclave raided Vault 13 on March 16, 2242; the vault's inhabitants are taken to the oil rig, so that the inoculation rendering humans immune to the FEV-based toxin could be tested.

At roughly the same time, the village of Arroyo was also raided, to acquire subjects to verify the effectiveness of FEV Curling-13. By Autumn of 2242, the testing was completed and the target toxin efficiency of 99.5% was reached. 250,000 gallons were manufactured and prepared for release into the jet streams. However, hours before the toxin could be released, the Chosen One infiltrated the oil rig, assassinated President Dick Richardson and Frank Horrigan and triggered a nuclear detonation, obliterating the toxin supply and averting global genocide.

Interactions with the player character

 * Charles Curling, the leader of the group, is encountered on Control station Enclave.

Appearances
The U.S. Chemical Corps appears only in Fallout 2.