부산대학교 도서관

There has been considerable experience in the United States regarding level-bottom capping operations in the New England area and in New York Bight. These operations involve placement of contaminated sediments at open-water sites by bottom dumping from hopper dredges or barges, forming a mound on the bottom followed by placement of a cap of clean sediment. More recent US capping experiences involve hydraulic placement of highly contaminated sediments from a Superfund project in New Bedford, Massachusetts, in preexcavated subaqueous pits. These sediments were capped by hydraulically placing clean sediment using a submerged diffuser. Other recent innovations include controlled placement of materials in thin layers by pipeline and from barges, recently accomplished in Puget Sound. Results from these projects and planned demonstrations of other capping procedures will extend capping experience in the United States to a wide range of project conditions.