ST. LOUIS (AP) — The Army Corps of Engineers says it's close to shoring up how soon contractors could begin removing treacherous southern Illinois rock formations impeding barge traffic in the drought-plagued Mississippi River.

The corps says it has hired Newt Marine Service of Dubuque, Iowa, and Kokosing Construction Co. of Fredericktown, Ohio, to do the work being expedited because of low levels of the Mississippi.

The corps is finalizing how quickly the companies get to the work site near the Illinois village of Thebes, do prep work and begin blasting the rock to remove it.