Table 15.

An example monitoring protocol from the benthic habitat and resources category for seabed scour and/or deposition at a commercial-scale installation.

	High cost	Low cost
Indicator(s) of the impact	Scour: increase in median grain size, decrease in organic content, decrease in seabed volume
	Deposition: decrease in median grain size, increase in organic content, increase in seabed volume
Methodology or technique to collect data	Particle size analysis, multibeam/interferometric bathymetry
Description of methodology or technique(s) for collecting data	Seasonal surveys, 5 years	Annual surveys, 3 years
	Grain size: *5-sample transect at 3 devices out to 200 m	Grain size: *3-sample transect at 3 devices out to 200 m
	Bathymetry: overlapping transects for 100% coverage (at least 0.5 m pixels) 1 km radius at 3 devices	Bathymetry: overlapping transects for 100% coverage (at least 0.5 m pixels) 500 m radius 3 devices
Methodology for analyzing data	ANOVA on median grain size, volume change estimate using mosaicked bathymetry models
Frequency and duration	1 preconstruction survey, seasonal operation, 1 postconstruction survey	1 preconstruction survey, annual operation, 1 postconstruction survey
Spatial scale	200 m–1 km radius around 3 devices	500 m radius around 3 devices
How well does this methodology account for environmental variability?	Seasonal and interannual variability	Interannual variability
Cost	$25 k/year, 5 years	$15 k/year, 3 years
Other considerations (e.g., advantages or disadvantages)	Can be combined with benthic community composition monitoring protocol

Type of data output required: time series values for median grain size and standard deviations, time series on volume at each turbine and standard deviation.