The International Association of Dredging Contractors (IADC) has released its new ‘Facts About’ publication on Environmental Equipment.
‘Facts About’ is a series of concise, easy-to-read leaflets which give an effective overview of essential facts about specific dredging and maritime construction subjects.
Each leaflet provides a kind of ‘management summary’ for stakeholders who need a quick understanding of a particular issue.
These leaflets are part of IADC’s on-going effort to support clients, consultants and others in understanding the fundamental principles of dredging and maritime construction because providing effective information to all involved parties is an essential element in achieving a successful dredging project.
Facts About: Environmental Equipment
Use of the term “environmental” or “remediation” dredging has evolved in recent years to describe dredging performed specifically for the removal of sediment contaminated at levels that can endanger marine life and human life.
Environmental dredging is executed for the specific purpose of removing hazardous wastes that are detrimental to ecosystems and it is conducted in a way to minimize the spread of contaminants to the surrounding waters during dredging.
Environmental dredging techniques aim to achieve a high concentration of dredged sediment with the lowest possible turbidity. They try to optimize the precision with which operations are done, for instance, to remove accurate thin layers so that the least possible quantities of contaminated material are dredged and therefore less material requires disposal, since secure disposal of contaminated material can be a challenge.
To do this, special ‘environmental dredgers’ have been developed. These are often modifications of cutter suction hoppers, backhoes and grabs. Other adaptations are the so-called “green valve” system developed for trailing suction hoppers, which reduces turbidity caused by overflow during the dredging process.