UPDATE 1-Deepwater traffic near normal on Miss. River-USCG

(Recasts, adds detail on queue, cleanup)

HOUSTON, July 29 (Reuters) - The movement of deepwater ships on the Mississippi River was nearly back to normal on Tuesday as cleanup of the worst spill in nearly a decade progressed, the U.S. Coast Guard said.

"Deep draft movement is approaching normal flow," a Coast Guard spokesman said. "Cargo operations are authorized following vessel decontamination and approvals."

There were 58 vessels and barge tows awaiting permission to move Tuesday, down from 182 Monday. Forty-one were southbound, and 17 were northbound, reflecting priority for inbound cargoes, he said.

The spokesman could not say how many of the ships moved or waiting were tankers, grain ships or other types of freight carriers.

The Coast Guard closed the river to vessel traffic between Mile 98 at New Orleans and Mile Zero at the Gulf of Mexico last Wednesday after a vessel collision spilled nearly 420,000 gallons (1,590,000 liters) of fuel oil in the river.

Traffic was stopped to protect workers and facilitate cleanup.

The river remained officially closed, but progress in the cleanup had allowed a gradual increase in traffic on this key shipping route for grain, coal and fuel exports from the U.S. heartland and crude oil imports from overseas.

"Cleanup has been cut from 12 to two hours a day, there's less oil in the river and also the oil is being contained to more out-of-the-way places," the Coast Guard spokesman said.