When NCR attempted to expand east, they needed railways to carry supplies to distant locations, especially places ripe for colonization. For this task, NCR used criminals from their Black Canyon prison who were approaching the end of their sentences. However, when NCR started to have financial problems, payments to the workers started coming up late or short. Eventually, the workers decided to take matters into their own hands, seizing the work stations and all the blasting powder they could find. These packs of criminals became powder gangs, blowing up any and all caravans and railways they came across.
The following is based on Van Buren and has not been confirmed by canon sources.
A prison complex utilized by the NCR, Black Canyon served as the NCR's solution to cheap manual labor. Porter of the 370th NCR Salvagers, as well as his team, had been imprisoned in 2248, after a failed robbery. Throughout 2249, members from Porter's team attempted to escape many times, though there was always nowhere to run and they were caught or surrendered. At least one escape was planned by NCR Lt. Gov Joseph Dodge, hoping that Porter would loop back to pick up the money from the failed robbery, but the escape he arranged only resulted in the 308th getting free, not the 370th.