Abstract
TOTAL E&P Angola organized, from the 13th to the 15th of November 2013, a large scale oil spill response exercise, called "LULA". The oil spill strategy for the response to a 50 000 bopd blow-out scenario in deep offshore Angola was implemented. Offshore resources were actually deployed and tested, including subsea response with a newly developed subsea dispersant injection system mobilized from Norway and operated from a newly designed and built Light Well Intervention Vessel, and surface response (dispersion, containment and recovery). The implementation of an onshore response plan, encompassing shoreline protection and clean-up, waste management and oiled wildlife response, was simulated. This exercise provided a unique opportunity to mobilize simultaneously a wide array of oil slick monitoring techniques at sea. The assessment of their domains of application and effectiveness was made possible thanks to a special permission given by the Angolan authorities to release a limited amount of crude oil at sea surface.
Daily monitoring was implemented to assess the drift and behavior of the spilled oil and to guide resources during the response operations. Several technologies were tested. Drifting buoys were launched to reflect the oil slick position in near real-time by satellite transmission. Aerial surveillance was carried out by helicopter and by fixed-wings OSRL aircraft (mobilized from Ghana) to provide detailed information about the oil slick (position, shape and location of thickest slicks). These techniques were complemented by one of the latest innovation of the TOTAL Group: the observation balloon BOOST. This balloon, fixed to a supply vessel, provides an overview of the slick from 150 m altitude through a camera which feeds back visible and infrared geo-localized images, thus enabling positioning the response vessels on the thickest parts of the slick and initiating response at first daylight. RADAR imagery was also collected by satellite. A set of techniques enabling 5 days oil spill drift predictions is combined in another Company innovation: SPILLWATCH service, which includes 3D currents and winds forecasts, oil subsea/surface behavior and slick drift modeling, and daily recalibration using the RADAR images.
The results obtained during LULA demonstrated the consistency of the various techniques and confirmed the possibility to track a slick during day and night time.
Being able to follow spilled oil at sea is part of the Company's responsibilities. These tests onsite will considerably improve our good practices and should benefit to the whole Oil & Gas Industry.
