Photoacoustic detection and monitoring of oil spill

The detection and monitoring of oil spills in marine environment are crucial to respond rapidly and efficiently and it is especially important in ice-covered areas. Detection and quantitative characterization of the affected areas as well as monitoring of remediation measures are critical for optimized cleaning operation and minimal environment impact. In the recent years, techniques of oil spill detection from under the ice with Remote Operated Vehicle (ROV) or Autonomous Underwater Vehicle (AUV), have been explored and have shown promising results. These techniques are based on ultrasonic or sonar technologies to quantify the oil volume and on optical techniques to obtain a chemical signature of the oil presence. In this paper we present a new promising technique based on photoacoustics for detection and sizing of oil spill under the ice, encapsulated within ice, or on open water. The technique has the advantage to provide signal in the presence of oil and no signal in its absence. It is also much less sensitive to alignment compared to ultrasonic and sonar techniques. Experimental results on detection of oil under the ice are presented and discussed. A first prototype with a scanning unit that can be operated in ROV is also presented. The solution proposed should be especially useful as a tool for emergency response, but should also be suitable when operated in AUV for monitoring high risky areas due to navigation, transportation or oil exploration and production.