VIDALIA — “Catastrophic in biblical terms” — those are the words District 32 Sen. Neil Riser used to describe the potential impact of the ongoing oil spill in the Gulf of Mexico.

As a member of the Louisiana Senate Homeland Security Committee, Riser and several other legislators were given a helicopter tour of the Louisiana coast Thursday by the Louisiana National Guard.

Riser said most of what he saw resembled the rainbow sheen left in the water by an outboard motor.

“You didn’t see a continual sheen along the coast, but what is misleading about that is that the lighter oil comes to the surface, leaving that sheen, and the heavier part below the surface,” Riser said.

The lighter oil had reached the outer edges of some of the marshes the group toured, and Riser said that the heavier oil is approximately 12 miles away from the marshes.

“It is slower moving than the lighter oil, so once that heavy body (of oil) moves into the marsh it is beyond catastrophic,” he said.

“I don’t know if we have ever had anything environmentally with the potential impact from what this is.”

Containing the oil to a given area has been an ongoing problem, and even as controlled burns and dispersants are being used, Riser said that the total number of oil booms in the entire United States would only cover 100 miles.

“It is just a small, small percentage of the exposure we have,” he said.

The oil is also starting to enter the gulf stream and head in the direction of Florida, and could destroy fisheries all across the gulf coast, Riser said.

“It is catastrophic in biblical terms no matter where it goes,” he said.

“I wish I could tell you it would go away, but it won’t.”

The oil spill first began April 20 after a massive explosion on the Deepwater Horizon oil rig, located approximately 41 miles off the coast.

Efforts to cap the well, located approximately 5,000 feet under water, were under way Friday.