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Research on the dynamics of cohesive sediments in relation to the dumping & discharge of contaminants in the Euro Shelf - AE0207

Description
R&D Summary Objectives:- Describe the behaviour of cohesive sediments e.g. mud, as a function of various environmental conditions (such as wind-waves and tidal currents) in order to assess the associated dispersal of radioactive and non-radioactive wastes. Key customer purpose:- Develop policy for dumping and waste disposal at sea on the basis of a better understanding of the behaviour of contaminants associated with sediments, and thus ensure that MAFF fully meets its responsibilities under national and international regulations.
Objective
1.A hydrodynamically 'clean' tetrapod(The MAFF tetrapod) has been developed and deployed for measuring currents near the sea bed, at a variety of sites with different bed types (mixtures of sand and mud). Further long deployments will be made during the winters of each year of the project. The instruments to measure suspended sediment concentrations will be upgraded as a result of past experiments. 2.A hydrodynamically 'dirty' tetrapod (The Quadrapod) has been designed and tested for the autonomous measurement of other key parameters )eg seabed micotopography, suspended particle concentrations, settling velocities and geotechnical properties of the seabed) requiring relatively bulky equipment which would unavoidably interfere with the current measurements. Instruments to make these measurements will be designed, tested and fitted on the quadrapod for the short-term and long-term deployments with the MAFF tetrapod. 3.A simpler hydrodynamically ' clean' tripod (The minipod) has been designed to be deployed with the MAFF tetrapod. These minipods will collect a sub-set of the measurements in space and, hence, determine spatial gradients in key parameters. 4.Other measurements of the hydrodynamic conditions in the area will be made using existing conventional current meters and water sampling equipment. Measurement of concentrations of naturally-occuring radionuclides will also be made to provide information on scavenging by particles as a result of resuspention by winds and tides.
Project Documents
• Final Report : AE0207: Final report Cohesive Sediments Dynamics Study (COSEDS)   (58k)
Time-Scale and Cost
From: 1988

To: 1994

Cost: £3,225,709
Contractor / Funded Organisations
CEFAS
Keywords
              
Fields of Study
Environmental Protection - Marine