Assessing Hydrocarbon presence in the waters of Port au Port bay, Newfoundland and Labrador, for AUV oil spill delineation tests

The waters adjacent to the Port au Port Peninsula, in Port au Port Bay, Newfoundland andLabrador, are known to be subject to release of hydrocarbons from natural oil seeps and oldabandoned oil wells. An investigation was done to determine whether there were sufficient oilcompounds present for planned autonomous underwater vehicle (AUV) test missions to developadaptive sampling algorithms to delineate oil spills. Fluorometers were used in-situ to measureoil concentrations. Oil-and-water samples were taken at selected waypoints for chemical analysisin the laboratory to validate the sensor measurements and to provide a ground truth. Only oneof the fluorometers was found to have a minimum detection level that was capable of sensingthe hydrocarbons in the water column. The water sample results indicated hydrocarbon levelsup to almost 30 ppm in the east side of the bay, just to the west of Shoal Point, but no detectablelevels on the west side of the bay. It was concluded that it would be possible to operate an AUVon a planned fixed mission with a pre-programmed search path and record the levels of signaldetected from fluorometers or other sensors. However, it would be difficult to implement anadaptive mission in this case because of the low levels of sensor signals resulting from the lowconcentrations of hydrocarbon present