LOS ANGELES REGION DREDGE MATERIAL MANAGEMENT:CSTF PURPOSE,GOALS,RELATIONSHIP TO PILOT/BENCH STUDIES

摘要

The multi-agency Los Angeles Basin Contaminated Sediments Task Force (CSTF)was established in 1998 to develop a long-term management plan by 2003,for dredging and disposal of contaminated sediments from coastal waters in Los Angeles County.The plan’s goal is to include measures to identify environmentally preferable, practicable disposal alternatives,promote multiuse disposal facilities and beneficial re- use,and support efforts for watershed management to control contaminants at their source.To identify the most appropriate sediment disposal alternatives,four pilot and/or bench scale studies were conducted and led by one of the CSTF executive members,the Los Angeles District Army Corps of Engineers.This paper describes how the CSTF identified and is evaluating the pilot and/or bench scale projects for the purposes of long- term dredge material management. rnOne of the CSTF’s objectives is to identify a“toolbox”of practical disposal alternatives that can be used by regulatory agencies and dredgers to select and evaluate suitable disposal options for proposed dredging projects involving removal of contaminated sediments.These options include various aquatic and upland disposal and beneficial re- use alternatives. rnMany groups around the country are grappling with these same problems and have generated extremely useful information pertaining to disposal alternatives.However,the CSTF discovered a need to conduct some pilot projects with local contaminated sediments to evaluate technical and economic issues related to a few very promising options.Therefore,the CSTF and U.S.Army Corps of Engineers are funding laboratory or field pilot projects to assess a confined aquatic disposal site,as well as cement stabilization,soil washing and soil blending techniques associated with beneficial re-use.