For the crew of the National Oceanic and Atmospheric Administration’s (NOAA) 208-foot hydrographic vessel Thomas Jefferson, switching its mission from ocean mapping to helping evaluate the impact of the Deepwater Horizon oil spill meant a little improvisation.
“We had to come up with some expedient solutions to short-term problems,” said the ship’s master, Cmdr. Shepard Smith, who also serves as lead scientist.
Taking water chemistry measurements and water samples was part of a three-week mission that began when the vessel left Galveston, Texas, on June 15.
One problem: Thomas Jefferson did not have sample coolers. So the crew went to Home Depot, bought two refrigerators and a chest freezer, lashed them on deck and put a strap on them to keep the doors from opening.
Thomas Jefferson is one of seven NOAA vessels working to assess the impact of the oil spill. NOAA operates a fleet of about 20 research and survey vessels that are crewed by a combination of NOAA commissioned officers and civilian mariners. Many serve both as deck officers and scientists, according to Smith.
Each vessel has between five and eight officers and between 12 and 24 crew, according to David Hall, spokesman for NOAA’s Office of Marine and Aviation Operations. Depending on the ship and the mission, each vessel also carries between four to 15 scientists.
The sheer magnitude of the Deepwater Horizon oil spill has kept NOAA vessels busy. “The scope of having this many NOAA ships working in coordination on a single project is unprecedented,” said Smith.
The other NOAA-operated vessels working on the spill are all fisheries research vessels: the 224-foot Gordon Gunter, the 209-foot Pisces, the 209-foot Henry B. Bigelow, the 187-foot Nancy Foster, the 170-foot Oregon II, and the 155-foot Delaware II.
Thomas Jefferson’s first mission was focused on the Loop Current, a stream of warm Caribbean water that enters the Yucatan Straits, heads north, and sometimes extends to the Gulf Coast, where it exits into the Florida Straits. Following the spill, a major concern was whether this current could provide a means for the oil to reach Florida and perhaps the Atlantic. During a second mission, Thomas Jefferson did continued testing for submerged oil in the deep water and worked within about 1,000 yards of the wellhead.
“It felt like you were sitting next to a campfire — there was that much heat coming off,” Smith said. “The air quality in the vicinity of that wellhead was pretty nasty.”
As the vessel was circling the wellhead and came on the downwind side, all ventilation systems were shut down and all crew were brought inside. They monitored the air quality and found that even on deck, the air did not exceed federal work standards for safety, “but we didn’t want to expose our crew any more than necessary,” Smith said.
This work was focused on understanding the mechanics of subsurface oil right from the wellhead.
Gordon Gunter conducted an eight-day oil detection mission near the wellhead in late May and early June. On its next mission, from June 14 to Aug. 8, the vessel surveyed marine mammals. Scientists were taking water and biopsy samples for analysis, and also tagging some animals to find out how they move between polluted and unpolluted waters. Scientists are specifically looking at the impact of the spill on the endangered sperm whale.
Henry B. Bigelow monitored subsurface oil from the spill and also collected water samples from 2,600 to 4,000 feet.
The first missions of Pisces and Oregon II were to survey reef fish, bottom-dwelling fish and shrimp in the eastern and western Gulf. The two vessels also took water samples. From July 14 on, Pisces was using echo sounders to test for oil and gas releases right near the wellhead, to help with testing of the wellhead’s integrity.
Oregon II embarked July 26 on a mission to collect samples of fish and shrimp off Louisiana in water depths of between 30 and 360 feet.
Nancy Foster conducted a July mission in the eastern Gulf of Mexico and the Florida Straits. Scientists examined oil, dispersants and tar balls in the water column and to collect zooplankton samples in areas impacted by the spill. Scientists also counted different fish larvae found in the upper ocean. At the end of July, a remotely operated vehicle was being used to investigate the impact the oil/dispersant mixture was having on deepwater bottom habitats.
Delaware II conducted a two-week mission in June and July catching tuna, swordfish and sharks to find out how the spill is affecting these species.
Their research was part of NOAA’s larger effort to determine what has happened to the oil.
An Aug. 4 report released by NOAA came up with a surprising conclusion: the vast majority of the approximately 4.9 million barrels of oil released into the Gulf had been removed or had dispersed.
Jane Lubchenco, NOAA’s administrator, said at an Aug. 4 press briefing that much of the dispersed oil is rapidly degrading and is very dilute. The report suggested that the environmental damage caused by the spill might be less than had been feared early on.
About 25 percent of the oil was directly removed, burned or skimmed; 25 percent naturally dissolved; 16 percent was naturally dispersed; and 8 percent was chemically dispersed. About 26 percent of the oil remains.
Lubchenco cautioned, however, that the harm was still substantial and the overall impact still largely to be determined.
“But diluted and out of sight doesn’t necessarily mean benign,” Lubchenco said. “We remain concerned about the long-term impacts, both on the marshes and the wildlife, but also beneath the surface, and are actively studying that.”
David A. Tyler