Search

Three rounds of water sampling were performed at the Berge Helene FPSO at the Chinguetti field in Mauritania using passive samplers attached to the FPSO to determine the levels of contamination that could potentially accumulate in organisms. Two rounds were carried out prior to the commencement of oil production (pre-PFW) and one following the start of produced formation water discharge (post-PFW). Although water was sampled at 3-m and 10-m depths, bioaccumulation data were possible to report only for 3-m depth due to the repeatable loss of samplers deployed at 10-m depth. The reason for these losses remains un-known. Retrieved passive samplers from each round were analysed for total bioaccumulative (petroleum) hydrocarbons, 9 phenols, benzene, toluene, ethylbenzene, xylene and 16 EPA polycyclic aromatic hydrocarbons. The accumulated amounts of chemicals during the two pre-PFW samplings were very similar and both of them can be considered to be representative for the pre-PFW phase. Surprisingly, the accumulated amount of chemicals during the post-PFW sampling round (i.e. after and during regular PFW discharges) was lower than in the pre-PFW sampling round. The most probable explanation is that drilling activities have stronger impact than the regular PFW discharges, but the possibility that the results were influenced by a variation in meteorological and hydrological conditions, such as ,e.g., direction and strength of the currents, could not be fully rejected. The biomimetic nature of the Empore® disk extraction was used to estimate total body residues of chemicals in biota. These values were compared with critical body residues for three toxicological effects to evaluate baseline toxicity of the environment under the FPSO. Results showed that the total body residue levels in the aquatic environment under the FPSO are below the no-effect level for sub-lethal fish toxicity. However, in all measurements the levels exceed safe level for effects on ecosystem (HC5): in pre-PFW sampling significantly, while in post-PFW only slightly. As these levels were observed directly at the source of possible contamination, the effects on the environment are likely to be substantially lower at increased distance from the FPSO.

An Environmental Impact Statement (EIS) prepared by Woodside (Perth, Australia) for the Chinguetti Development Project in Mauritania identified potential environmental effects from routine Produced Formation Water (PFW) discharges on the marine environment. Adverse effects on the industrial fisheries of Mauritania in particular, were identified as one of the key environmental risks represented by the project. Woodside therefore made a commitment to monitor PFW discharges and as a first step biological and water sampling was prepared prior to, and following first oil production from the Chinguetti Project. Woodside, recognizing the importance of involvement of Mauritanian institutions in monitoring studies, requested that the project be undertaken in association with National Mauritanian Institute for Oceanographic and Fisheries Research (IMROP), which is the Mauritanian body responsible for protection of the sea. In addition, part of the project is dedicated to improvement of IMROP’s capacity to perform sampling and to analyze the water and biological samples, so that over time all required activities could be performed by IMROP. The project is being undertaken by the Marine Resources Assessment Group (MRAG) of United Kingdom and the Institute for Marine Resources and Ecosystem Studies (IMARES) of the Netherlands. The capacity building activities are being shared by both partners and coordinated by MRAG. This document provides a final report on the capacity building activities performed by IMARES within the Woodside Chinguetti PFW Baseline project. The report covers the list of all activities performed, the discussion and evaluation of the current capacity of IMROP and suggestions/recommendations for further activities.

Two sampling rounds of Sardinella aurita were conducted in the waters off the coast of Mauritania to evaluate levels of contamination prior to the commencement of oil production and following the start of produced formation water discharge.

An ecotoxicological study of produced formation water (PFW) from the Berge Helene FPSO at the Chinguetti oil field, operated by Woodside in Mauritania was performed. The study was requested by MRAG Ltd as a part of Woodside’s Environmental Monitoring Plan.