EUMARSAND — A European approach to Marine Aggregate Dredging

'Eumarsand', the European Sand and Gravel Resources site to be seen at www.azti.es/eumarsand/background.htm could prove to be a step toward responsible sanity as it directly states the environmental harm brought about by offshore aggregate mining. It further points out that there are currently no coherent policies to deal with the situation. Here follows a quote from the content.

EUMARSAND: BACKGROUND INFORMATION

1. Overview

• Marine aggregates (sand and gravel) have emerged as a strategic mineral resource.
• Sand: naturally occurring unconsolidated rock particles between 63 and 2000µm. Gravel: particles between 2mm and 63mm They are formed by fluvial (river), lacustrine (lake), glacial, marine or residual (weathering) processes.
• Sand and gravel are mostly used for construction either as aggregate in concrete, as road base or as fill. It is also used for beach nourishment and shore protection and for land reclamation. Sand in industrial use represents a lower volume but a higher market value (glass making, abrasives and moulding in foundries).
• Annually, approx. 40 million m3 of marine sand and gravel extracted from North European inner Continental Shelf. 15% of the extracted materials are used outside the country of production. Need for realisation of large-scale infrastructure projects for coastal areas of Europe. New resources must be found. Environmental concerns must be addressed.

2. Impacts of marine sand extraction

Effects of marine aggregate extraction which have been considered include:

1. Significant alteration of regional sediment transport patterns and coastal morphodynamics:
   Changes in seabed elevation may:
   • alter inner shelf flows.
   • enhance the wave energy towards the coast.
   • change the active beach-nearshore sediment systems and budgets.
   • enhance coastal erosion and retreat.
2. Harmful effects on fauna, flora and water quality in the area of mining:
   • Destruction of benthic habitats and species, such as fish and shelfish populations
   • The formation of turbid plumes, of fine-grained sediments, during extraction may affect the benthic ecology, far from the extraction site.
   • Creation of large depressions on the seabed (depending upon extraction method) where anoxic conditions may develop.
3. Disturbance of cultural heritage sites e.g. shipwrecks of archaeological interest.
4. Potential conflicts of interests exist between marine aggregate industry and other sea-bed users: Fisheries, Shipping, Oil Industries, and, more recently: Offshore Windmill Farms (for power generation).

3. Motivation

It appears that there are:

1. no coherent policies and regulations, even between long-standing trade Partners.
2. disparities between the different EU Member States, in 'know-how' necessary to address effectively the various scientific problems related to:
   • resource prospecting; and
   • the environmental impacts of marine aggregate mining.

Thus, need at European level, for integrated and coherent approaches to resource prospecting:

1. environmental considerations; and
2. the development of a science-based approach to management.