Assessment and Managemtn of Historical pulp Mill Reeleases to a Marine Embayment-How Toxic Are The Sediments and What Makes Tiem Toxic?

摘要

As required by the U.S. Environmental Protection Agnecy, a sediment investigation was conducted in Ward Cove, Alaska, for the Ketchikan Pulp company to determine the potential threat to human health and the environment posed by sediment adjacent to the mill. Historical releases of pulpng by-products and log handling activities in ward Cove resulted in a complex mixture of chemicals and partialy digested orgainc matter in sediments near the mill. Based on an integrated analysis of site-specific data on sediment chemistry and sediment toxicity, it was concluded that the natural degradatin products of organce matter wre likely responsible ofr hte observed toxicity to benthic organisms. Measureable toxicity was limited and could be explained largely by the life histories and behavioral patterns of the organisms tested. An analysis of case studies of similar, organically enriched environments suggests that natural recovery is a viable remedial alternative for organic-rich sediment andthat active remediation, if conducted at all, should be limited to thin capping. COnclusions regarding sediment toxicity are also relevant to log hadling facilities, which are coming under increasing regulatory scurtiny.