HOUSTON—The U.S. Coast Guard and Jefferson Parish officials said an oily substance was washing ashore in parts of Louisiana that were among the hardest hit by BP PLC’s Deepwater Horizon oil spill last year.
The Coast Guard and a parish spokeswoman said they had mobilized oil-spill-response equipment and the Coast Guard had hired a contractor to lay containment booms in hopes of stopping the substance from penetrating inland waters and ecologically sensitive shorelines.
Photos taken by Jefferson Parish officials show globs of reddish matter coming ashore on Elmer’s Island, a state wildlife sanctuary, that looks very similar to what washed onto northern Gulf beaches during last summer’s oil spill.
Other photographs, taken off Port Fourchon, show vast stretches of the Gulf’s surface coated in a thin film and streaked with bright orange streams of thick matter.
The substance was first reported along Louisiana’s coast Saturday, said Kriss Fortunato, a Jefferson Parish spokeswoman. On Sunday, the substance came ashore in greater amounts, coating miles of beaches, she said.
Jefferson Parish had no official estimate of how much of the material had reached land or lurks in near-shore waters, but “it’s a significant amount,” Ms. Fortunato said. Sheen believed to be associated with the goopy material reportedly stretched on the Gulf’s surface for miles, she said.
Officials are still trying to figure out what the substance is and where it came from. The Coast Guard said it doesn’t suspect that it is residual oil from BP’s 4.9 million barrel spill.
Both the local government and the Coast Guard have taken samples and of the matter and are performing tests independent of one another.
So far, the substance has washed ashore on Grand Isle, Fourchon Beach and Elmer’s Island. A rainbow-sheen-like slick that is associated with oil spills has also been reported on the surface of Timbalier Bay, the Coast Guard said.
Some 10,000 feet of boom is on Grand Isle and an additional 19,000 feet of both hard and absorbent floating barrier has been ordered for the operation, said Capt. Jonathan Burton, who is coordinating the response, in a news release.
The Coast Guard has hired environmental-response company ES&H to begin cleaning up the oily substance and has authorized the disaster-response contractor to buy whatever additional boom and equipment is needed to contain and clean up the substance.
In a separate investigation, the Coast Guard has determined that what was reported Saturday as potentially a miles-long oil slick is actually a plume of silt emanating from the Mississippi River.
Samples from the plume taken from a Coast Guard cutter have found only trace amounts of oil and grease in the murky cloud.
“At this point, the dark substance is believed to be caused by a tremendous amount of sediment being carried down the Mississippi River due to high water, possibly further agitated by dredging operations,” the Coast Guard said in a news release.