ARZC
| Arizona and California Railroad | 3 |
ATSF
| Atchison Topeka & Santa Fe | 2 |
GREX
| Georgetown Rail Equipment Company | 1 |
MP
| Missouri Pacific | 3 |
QUAX
| Redstreak, LLC | 2 |
SP
| Southern Pacific | 4 |
SPMW
| Southern Pacific Maintenance of Way | 5 |
SSW
| St Louis Southwestern (Cotton Belt) | 4 |
UP
| Union Pacific Railroad Company | 3 |