Assessing the potential impact of water-based drill cuttings on deep-water calcareous red algae using species specific impact categories and measured oceanographic and discharge data.

The potential impact of drill cuttings on the two deep water calcareous red algae Mesophyllum engelhartii and Lithothamnion sp. from the Peregrino oil field was assessed. Dispersion modelling of drill cuttings was performed for a two year period using measured oceanographic and discharge data with 24 h resolution.

The effect of sediment mimicking drill cuttings on deep water rhodoliths in a flow-through system: Experimental work and modeling.

The impact of sediment coverage on two rhodolith-forming calcareous algae species collected at 100m water depth off the coast of Brazil was studied in an experimental flow-through system. Natural sediment mimicking drill cuttings with respect to size distribution was used. Sediment coverage and photosynthetic efficiency (maximum quantum yield of charge separation in photosystem II, ϕPSIImax) were measured as functions of light intensity, flow rate and added amount of sediment once a week for nine weeks.

Long- and short-term effects of smothering and burial by drill cuttings on calcareous algae in a static-renewal test.

Discharge of drill cuttings into the ocean during drilling of offshore oil wells can impact benthic communities through an increase in the concentrations of suspended particles in the water column and sedimentation of particles on the seafloor around the drilling installation. The present study assessed effects of water-based drill cuttings, barite, bentonite, and natural sediments on shallow- and deep-water calcareous algae in short-term (30 d) and long-term (90 d) experiments, using 2 species from Peregrino's oil field at Campos Basin, Brazil: Mesophyllum engelhartii and Lithothamnion sp. The results were compared with the shallow-water species Lithothamnion crispatum.