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Coast Guard tests Arctic oil recovery Research team tests effectiveness in sea-ice conditions of a variety of technologies for monitoring and recovering spilled oil Alan Bailey Petroleum News
In early September a team from the U.S. Coast Guard Research and Development Center, working in conjunction with other federal agencies and with other organizations, conducted an exercise involving the testing of potential oil spill response technologies in sea ice in the Arctic Ocean. The exercise, a part of Coast Guard District 17’s Arctic Shield 2013 program, involved the sailing of the U.S. Coast Guard Cutter Healy several hundred miles north of Barrow, in the boundary between the Beaufort and Chukchi seas, to deploy air, surface and underwater assets in a variety of sea ice conditions, Rich Hansen branch chief in the U.S. Coast Guard Research and Development Center, told Petroleum News.
The Healy, a Coast Guard icebreaker, is commonly used as a platform for Arctic offshore research.
Benefits and issues The concept was to try out different technology types, such as unmanned aerial or underwater vehicles, rather than specific pieces of equipment, to see what benefits each type of technology might bring and to identify any issues that need to be addressed when using the technology in Arctic ice conditions, Hansen explained. The team on the Healy also wanted to try out the practicalities of downloading data from the surveillance equipment and then assessing the data onboard the ship.
And the test flights of two small, unmanned aerial systems were the first ever tests of this type of system in the Arctic Ocean, the Coast Guard has said.
The National Oceanic and Atmospheric Administration and the University of Alaska Fairbanks provided the unmanned aerial systems for the exercise, while the Coast Guard and the Woods Hole Oceanographic Institute supplied unmanned underwater vehicles. The Bureau of Safety and Environmental Enforcement, or BSEE, funded a drifting buoy.
First Arctic test With the exception of the unmanned aerial systems, the equipment deployed in the tests had previously been tried out in ice conditions in the Great Lakes. But this was the first test in the Arctic Ocean, Hansen said. Testing of Arctic oil spill response equipment has also taken place in tanks in facilities such as BSEE’s Ohmsett facility in New Jersey. The Woods Hole Oceanographic Institute has been using its unmanned underwater vehicle, in conjunction with the BSEE, to test techniques for detecting oil under ice, Hansen said.
Several locations During its voyage the Healy stopped at several locations, each in different ice situations, to enable testing to be conducted in conditions ranging from new first-year ice to older and thicker ice, Hansen said. Most of the testing took place in broken ice, with the Healy pulling alongside an ice floe. However, at one location the vessel carved its way into a continuous ice pack.
In addition to deploying unmanned aerial vehicles above the ice, the team deployed unmanned underwater vehicles for various simulated oil spill response missions. And, rather than spilling actual oil, the team tipped oranges into the water to determine where an oil slick might be pushed by wind and wave action. The team also used peat moss to simulate the manner in which oil might be washed under or over the ice, Hansen said.
The team tried the deployment of a Coast Guard oil skimmer from the Healy, maneuvering the skimmer from a crane, to assess the practicalities of positioning the skimmer in the nooks and crannies along the edge of an ice floe.
Successful deployment The team was able to successfully deploy all of the technologies that it had taken on its Arctic mission, Hansen said. And, in trying out the equipment, there were some significant lessons learned.
For example, it proved impractical to launch the aerial systems in wind strengths exceeding 25 knots. And the low ceilings and foggy conditions experienced on most days limited the team’s ability to launch the aerial systems and shortened the durations of flights. But, with batteries warmed before use, the systems were able to operate successfully, despite low air temperatures.
On the other hand, low water temperatures did reduce the operational duration of unmanned underwater vehicles by about 50 percent.
With global positioning system, or GPS, navigation not possible under ice, an underwater vehicle depends on inertial navigation and other systems to maneuver its way below ice floes. And the team was able to successfully demonstrate the use of a vehicle below a variety of different ice thicknesses and in open Arctic water, conducting different mission profiles, Hansen said.
When testing the Arctic skimmer the team identified a need for modifications to the skimmer, to provide better protection from ice damage, Hansen said.
A novel repair And the team found a novel way of repairing a remote operating underwater vehicle, when an aluminum flange in a vehicle was bent after the vehicle became entangled in ice during recovery of the vehicle from the water. The team used a 3-D printer that it had brought on the voyage to manufacture a replacement plastic flange that enabled the vehicle to go back into service, Hansen said.
Data evaluation For assembly of data downloaded from the various aerial and underwater vehicles, the team tried the use of the National Oceanic and Atmospheric Administration’s ERMA mapping and data management system that had been successfully employed during the Deepwater Horizon response in the Gulf of Mexico. With no high-speed access to the Internet at the remote location of the Arctic testing, the team used a standalone version of the system, using the system to assemble information from the different technology types under test and assessing the potential value of the information to an on-scene commander during an actual Arctic oil spill response, Hansen said.
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