| 1. |  | Acidizing tank truck parked at Amerada Corporation's Joseph Rice 1 oil well, near Tioga, N.D. | Petroleum workers; Petroleum industry; Oil wells; Oil well drilling rigs; Trucks; Tankers; | Two tanker trucks parked by an oil well structure. There is a laborer crouched on the top of one of the trucks working with a hose. |
