Follow-up measures

Benthos/water/sediment monitoring

Objectives and methodology

This multiple monitoring has 3 distinct compartments, benthos/water/sediment is divided into 3 sub-parts:

A) Bio-assessment of benthic macrofauna and geochemical characterization of sediments.
This involves monitoring epifauna and infauna around 4 stations, representative of the diversity of habitats present on the study site.
Two stations are located on soft substrates, two on substrates considered hard. Each of these stations is made up of 4 substations, positioned following a potential incidence gradient in the major axis of the current. Loose substrates: Sampling using i) a standardized grab (0.1m²; 5 replicates) and ii) a towed video system allowing transects to be carried out.
An average sample of sediments will be taken for geochemical analyzes in the laboratory. Hard substrates: Production of a fixed point video sequence lasting 10'.

B) Monitoring of water quality and water mass.
Sampling of sea water at 1 station located in the central position of the wind farm perimeter.
Sampling using a Niskin trigger bottle. The sample is constituted at a single average depth.

C) Monitoring the impact of sacrificial anodes.
Task 1: Quantification of anode corrosion products in the environment (seawater, sediments).
This “task” (field/dosage) is fully integrated into the monitoring protocol for water quality, water bodies and sediments.
Task 2: Assessment of the health and environmental risk induced via potential mechanisms of bioaccumulation of aluminum and zinc.
The species monitored as part of this monitoring are the scallop (Pecten maximus), a filter-feeding bivalve, the whelk (Buccinum undatum), a scavenger gastropod and the common pout (Trisopterus luscus), a predatory fish. The sampling effort for these species comes from experimental fishing carried out during the monitoring of fisheries resources.