A leak was discovered on a crude oil pipeline (diam.: 40”, maximum service pressure: 40 bar, built in 1972) composed of welded rolled tubes. The accident occurred on a Natura 2000 site in the Crau Natural Reserve, home to several protected species. A park warden sounded the alarm and the operator activated the pipeline’s emergency plan. Rescue crews and various administrative departments were onsite by 8:30 am. Aerial reconnaissance was performed and a safety perimeter set up. A “geyser” 3 to 4 m high gushed from a “buttonhole” rupture 15 cm wide and 1.8 m long on the longitudinal weld. The Prefecture convened a crisis monitoring cell at 11:15 am. The Secretary of State for Ecology arrived on the scene at 4:30 pm, and the court was seized. The Prefecture requested a precise evaluation of environmental impacts. According to the operator, the pipe break was due to a fatigue crack caused by the “roof effect” at the level of a longitudinal weld bead. The damaged tube was replaced by a new one; others were inspected and reinforced as a preventive measure. 5,4000 m3 of crude oil were discharged over a 5-ha land area. Surveys, coring and analysis of land are made to thoroughly assess the impact of pollution on the area. The water table is situated between 9 and 12 m depth, 72 piezometers were gradually installed in the following months to monitor the impact of pollution on groundwater together with a hydraulic barrier to contain the possible migration of the pollution. Analyses carried out regularly by the operator of the pipeline at the request of the authorities showed that no hydraulic capture downstream, either for irrigation, animal feed or human consumption, has been affected. Many studies were conducted to assess the impact of the accident on the local fauna and flora of the reserve. However, the consequences are difficult to assess beyond the polluted area due to a lack of accurate baseline even within a nature reserve. The Coussoul (flora) is yet destroyed over 5 acres. A year after the accident, the operator claimed having spent 50 million euros to “treat” the consequences of the leak, including a dozen for environmental restoration. On the whole, at the end of 2010, more than 73 000 tons of contaminated soil have been disbursed, then transported to a processing centre of a neighbouring department. These lands came from the stripping of polluted soils over a 40 cm depth. In the 5 ha area, a depositing was carried out with local materials transferred from a nearby quarry, respecting the original structure of the soil. The surface layer was reconstructed by directly transferring the Coussoul taken from areas not yet exploited of the quarry. Scientific monitoring is planned to observe the recovery of this Coussoul. The work is completed April 15, 2011. Given the succession of accidents that occurred during 2009 in the chemical and petroleum industries, as well as in the pipeline transport of hazardous materials sector, a meeting on industrial safety and environmental protection was organised in September 2009 between the Secretary of State for Ecology and key leaders in these sectors. Participants submitted proposals for improving safety at their installations, by means of strengthening controls and maintenance on ageing facility, while paying greater attention to ecologically-sensitive zones with the aim of better caring for protected species / zones. Further to this accident and as an experiment, the Secretary of State launched in August 2010a project to build a natural reserve near the affected area to “cultivate assets” that could offset negative impacts on biodiversity. For that purpose, a specialized company will restore rare and endangered species habitat by transforming an industrial orchard in a pasture zone.

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