Remote Sensing of Oil In and Under Ice in a Climate-Controlled Test Basin

Abstract

Abstract (2017-111) The ability to rapidly detect and delineate an oil spill in an Arctic environment is critical for efficient and effective response. The International Association of Oil and Gas Producers (IOSP), Arctic Oil Spill Response Technology – Joint Industry Programme (JIP) funded a novel controlled laboratory experiment to assess the relative efficacy of a variety of remote sensing instruments. This unbiased evaluation of existing and emerging technologies was recently conducted in the Ice Engineering Test Basin at the U.S. Army Engineer Research and Development Center’s Cold Regions Research and Engineering Laboratory (CRREL) in Hanover, New Hampshire, USA. CRREL provided the unique testing environment for sensor evaluation using the 120 ft. long by 30 ft. wide by 8 ft. deep Test Basin. The refrigerated Test Basin was filled with a manufactured saltwater solution and an 80 cm sea ice sheet was grown with fifteen individual containment hoops. Within the individual containment hoops, oil volumes were injected at predetermined ice thicknesses leading to oil encapsulation at differing ice depths. The Prince William Sound Oil Spill Recovery Institute assembled a team of remote sensing experts to select, operate and interpret sensors to examine and validate oil detection capabilities in level sea ice. Testing covered the full ice cycle from fresh oil and encapsulated oil in growing ice to migrating oil during ice melt out. Five aerial sensors were attached to a cantilevered boom on a motorized carriage operating above the ice surface, while at the bottom of the tank were nine subsea sensors installed on a computer-controlled traveling underwater platform Ice cores were obtained outside the hoops during ice growth and in designated hoops during the melt-out phase, with the objective of characterizing ice structure and oil migration using crystallography and CT scanning. Environmental measurements that would affect sensor performance such as resistivity, acoustics, air, ice and water temperatures were also recorded. This experiment provided a comprehensive side-by comparison of the sensors evaluated, while correlating measurements with the ice properties. The paper will provide a full description of the hoop layout plan, the oil injection process, and the measurements schedule that minimized sensor interference.