W4 PM Sediment Quality Assessment
Wednesday, 16 November 2005: 1:50 PM - 5:30 PM in Ballroom 4

(MAX-1117-826386) Assessing impact and recovery of infauna in an area of oil and gas exploration in the south Caspian Sea.

Maxon, C.¹, Tait, R.², Parr, T.³, Newton III, F.⁴, ¹ CH2M Hill, San Diego, CA, USA² ExxonMobil Production Company, Houston, TX, USA³ Terry Parr Consulting, San Diego, CA, USA⁴ Battelle Memorial Institute, Carlsbad, CA, USA

ABSTRACT- Physical, chemical, and biological data comprise the sediment monitoring triad typically used to gauge impacts from offshore oil exploration activities, where benthic communities are at risk from discharged drilling cuttings and adhered synthetic muds. This study examines the effects of drilling-related hydrocarbons, organic carbon, and sediment grain size on resident benthic communities after the discharge of cuttings and synthetic muds at an exploration well site in the south Caspian Sea. Linear alpha olefin (LAO) and petroleum hydrocarbon indices/tracers are identified and related to abundances of key species, including opportunistic foragers (e.g., ostracods) and sensitive amphipod crustaceans. The approach, which is applicable to similar contaminated sediment studies, focuses on LAO and saturated hydrocarbon degradation processes and the associated recovery of resident benthic communities over time.

Key words: synthetic drilling muds, sediment investigations, benthic infauna, Caspian Sea