A chemical spill today at a Des Moines meatpacking plant contaminated two workers on the scene. Des Moines Fire Chief Ron Wakeham says a tank of “feret” chloride was being pressurized, which is done right before it can be unloaded, but the tank suddenly ruptured.Wakeham says a softball-sized hole in the tank can’t be repaired by hazardous material experts — and the four-thousand gallons in the tank continues to leak.Wakeham says a team from Ankeny and another from Illinois will try to transfer the chemical into another container. The accident happened at about 11 this morning. The two workers were stripped of their clothing and scrubbed down at the scene. The fire chief says the two were successfully “decontaminated” and are back on the job.