tailieunhanh - COASTAL AQUIFER MANAGEMENT: monitoring, modeling, and case studies - Chapter 10

Phân tích không chắc chắn Nước biển xâm nhập và tác động cho Giao thông vận tải hạt nhân phóng xạ thử nghiệm hạt nhân ngầm Amchitka đảo Tất cả các nghiên cứu về các quá trình bên dưới bề mặt đối mặt với những thách thức trình bày bằng cách quan sát hạn chế của môi trường quan tâm. Bởi bản chất của nó, các đặc điểm chi tiết của dưới bề mặt ẩn và nỗ lực thu thập dữ liệu thường bị cản trở bởi hạn chế về kỹ thuật và tài chính. Kết quả là không chắc chắn. | CHAPTER 10 Uncertainty Analysis of Seawater Intrusion and Implications for Radionuclide Transport at Amchitka Island s Underground Nuclear Tests A. Hassan J. Chapman K. Pohlmann 1. INTRODUCTION All studies of subsurface processes face the challenge presented by limited observations of the environment of interest. By its very nature the detailed characteristics of the subsurface are hidden and data collection efforts are generally hindered by technical and financial constraints. The result is that uncertainty is a factor in all groundwater studies. Seawater intrusion environments present both special opportunities and special challenges for incorporating uncertainty into numerical simulations of groundwater flow and contaminant transport. Opportunities come from the constraints that the seawater-freshwater system provides challenges come from the numerically intensive solutions demanded by simultaneous solution of the energy and mass transport equations. The impact of uncertainty in the analysis of contaminant transport in coastal aquifers is an important aspect of evaluating radionuclide transport from three underground nuclear tests conducted by the . on Amchitka Island Alaska. Testing was conducted in the 1960s and very early 1970s on the Aleutian island to characterize the seismic signals from underground tests in active tectonic regimes and to avoid proximity to high-rise buildings and resulting ground motion problems. As the . Department of Energy focused on environmental management of nuclear sites in the 1990s a decision was made to revisit contaminant transport predictions for the island taking advantage of the advances in the understanding of island hydraulic systems and in computational power that occurred in the decades after the tests. Though the general geologic conditions are similar for the three tests they differ in their depth and thus position relative to the freshwaterseawater transition zone TZ . Amchitka is a long thin island separating .