Major Hazards - Seamlessly Embedding Considerations of the Environment

Abstract

TOTAL have recognised the fact, that there has been a need to put more focus on the environmental aspects associated with major accidents hazards. Major accidents as defined by the Offshore Installations (Offshore Safety Case) Regulations 2015 have been specifically assessed by the UK affiliate to identify if they could result in a Major Environmental Incident(s) (MEIs); in line with the EU Directive 2004/35/EC on environmental liability with regard to the prevention and remedying of environmental damage. Hydrocarbon releases of over 1,000bbls have therefore been modeled using the OSCAR software for events such as topside / subsea releases and wells blow outs in order to define fate and location of hydrocarbons from these releases. The exposure/effect (acute mortality, population loss, quantity of oil reaching/endangering shoreline habitats) of the releases on Valued Ecosystem Components (VECs) has then been assessed to define restitution time of the relevant organisms/habitats. Results of the modeling have been assessed so that any event that has a potential effect on the VECs classed by the Company as "Catastrophic" (>3years restoration time) or above is classed as MEI. The incidents not identified as MEIs are then screened along with other liquid releases using a complementary method. This method utilises a matrix to define the environmental severity, based on the volume and toxicity of the release as well as the sensitivity of the marine environment and when relevant (shoreline) the extent of the release. The above Offshore Safety Case regulation defines Safety and Environmental Critical Elements (SECEs) as "parts of an installation where either (a) failure could cause or contribute substantially to a major accident or (b) it has a purpose to prevent, or limit the effect of, a major accident". For major accidents potentially resulting in MEIs, a review of existing barriers was undertaken to demonstrate their adequacy and sufficiency. As an outcome of this process, Critical Elements performance standards were reviewed and amendments proposed as required.