The clean up after Wednesday's oil spill continues, and so do the restrictions on the Mississippi River.

"It is closed to traffic unless the captain of the port releases that particular vessel," said Steve Carleton, Senior Chief with the U.S. Coast Guard.  Priority,  he says, is based on economic impact.

So far only a few ships have been allowed to sail southbound and only one ship, an oil tanker named  "The Over Seas New York" has been allowed to continue on northbound.  Today, the captain of the ship received the final okay from the U.S. Coast guard.

Still, approval for ships on the river is limited.  Tourist Muriel Edwards and her family are in New Orleans for the weekend from Alabama and had their sights set on taking a dinner cruise.  "But they told us the river was closed," she said.  "So that's too bad."

The ships that are approved, however, must be carefully cleaned.  "We are pressure washing those vessels and then have to be, again, visually looked and inspected and signed off and then released," said Carleton.

The cleaning process can take several hours per ship.  But Carleton says it's the only way to prevent any more harm to the Mississippi River.  "They could be dragging oil in area that we don't already have oil."

Meanwhile, the barge that leaked all of the oil is still in the water.  Federal and state agencies are now working on a plan to remove it.  "We assume that most of the oil left the barge," said Carleton.  "But there could still be pockets of it left inside there."

Of the 420,000 gallons of oil that have spilled into the river, Carleton says about 31,000 gallons of an oil-water mix have been sucked out.  At this point, however, there is no telling how much of that is actually water, and how much is oil.