This data package documents the technical basis for selecting physical and hydraulic parameters and input values that will be used in river modeling for Hanford assessments. This work was originally conducted as part of the Characterization of Systems Task of the Groundwater Remediation Project managed by Fluor Hanford, Inc. and revised as part of the Characterization of Systems Project managed by PNNL for DOE. The river data package provides calculations of flow and transport in the Columbia River system. The module is based on the legacy code for the Modular Aquatic Simulation System II (MASS2), which is a two-dimensional, depth-averaged model that provides the capability to simulate the lateral (bank-to-bank) variation of flow and contaminants. It simulates river hydrodynamics (water velocities and surface elevations), sediment transport, contaminant transport, biotic transport, and sediment-contaminant interaction, including both suspended sediments and bed sediments. This document presents the data assembled to run the river module components for the section of the Columbia River from Vernita Bridge to the confluence with the Yakima River. MASS2 requires data on the river flow rate, downstream water surface elevation, groundwater influx and contaminants flux, background concentrations of contaminants, channel bathymetry, and the bed and suspended sediment properties. Stochastic variability for some input parameters such as partition coefficient (kd) values and background radionuclide concentrations is generated by the Environmental Stochastic Preprocessor. River flow is randomized on a yearly basis. At this time, the conceptual model does not incorporate extreme flooding (for example, 50 to 100 years) or dam removal scenarios.
Revised: December 9, 2006 |
Published: August 1, 2006