Long Term Management Strategy For Dredged Material Disposal For Naval Facilities At Pearl Harbor Hawaii Phasw Ii Evaulation Of Alternatives PDF Download

This report documents Phase II of a three-phase study to develop a Long-Term Management Strategy (LTMS) for Pearl Harbor. Physical and chemical characterization and contaminant pathway testing and analysis of Pearl Harbor sediment were performed for the proposed Waipio Peninsula confined disposal facility (CDF). Modeling was performed to support design/management/operations decision making and contaminant pathway analysis. Physical characterization included a number of geotechnical tests including grain-size analysis, Atterberg limits, soil classification, specific gravity, moisture content, self-weight and standard oedometer consolidation, and sedimentation. Chemical characterization included bulk sediment chemical analysis, toxicity characteristics leaching procedure (TCLP), and ambient water chemical analysis. Pathway testing included the modified elutriate test for effluent quality, the simplified laboratory runoff procedure (SLRP) for runoff quality, and diethylene triamine pentaacetic acid (DTPA) extraction for plant uptake. Using characterization data, leachate quality was predicted based on equilibrium partitioning of the contaminants between the soil and water. Air quality was estimated from computation of contaminant volatilization. The results of the Phase II study show that disposal of Pearl Harbor dredged material unsuitable for ocean disposal in an upland CDF on Waipio Peninsula is technically feasible. Disposal in an upland CDF poses no significant impacts on human health. Potential contaminant in releases by effluent, runoff, plant uptake, and animal uptake pathways pose small environmental impacts that should be acceptable with proper operation, management, and controls. Copper, arsenic, and ammonia concentrations in the effluent and runoff exceed water quality standards for toxicity but except for ammonia are similar to the contaminant concentrations in the background site water.