Solute Flux Rate Uncertainty Evaluation at a Monitored Boundary

Limitations on data collection density, aggregated spatial and temporal modeling scales, and variations in time can lead to substantial uncertainty in estimated ground water and solute flux rates. Difficulties associated with quantitative characterization of uncertainty often lead to use of conservative assumptions in management decision-making processes, which can lead to non-optimal resource management. This poster describes a computational method for estimating solute flux rate uncertainty at a monitored boundary that can be programmed on an ordinary spreadsheet application and discusses parameter estimation approaches. This method produces results comparable to those produced by Monte Carlo simulation under a reasonable range of assumptions. Two alternative conceptual models at the monitored boundary can be used, one in which the entire area of interest is treated in an integrated manner and the other in which the area of interest is segmented into zones. This poster addresses only the segmented approach. Case study results not shown here indicate that the conceptual model choice has an impact on the analysis results. Use of uncertainty analysis to evaluate likelihood of exceeding target impacts on receiving waters is also illustrated.