The FRAMES software is currently designed for deterministic environmental and human health impact models. The Sensitivity/Uncertainty Multimedia Modeling Module (SUM³) software product was designed to allow a statistical analysis using existing the deterministic models available in FRAMES. SUM³ is an available option under the Sensitivity/Uncertainty Module in FRAMES. SUM³ randomly samples input variables and preserves the associated output values in an external file available to the user for evaluation. This enables the user to calculate the deterministic values with variable inputs, producing a statistical distribution of the results. A typical application of the uncertainty analysis is to indicate the relative conservation of the deterministic result.

Although SUM³was originally developed as a sensitivity/uncertainty tool for use with the Multimedia Environmental Pollutant Assessment System (MEPAS^©), it is not restricted to MEPAS^© models. SUM³ can now be used with other deterministic environmental models through the FRAMES software package with other available tools, such as the Generation II (GENII) software system, which is a Hanford environmental dosimetry system. Within FRAMES, SUM³ allows the user to conduct a sensitivity and/or uncertainty analysis to understand the influence and importance of variability/uncertainty input parameters on the constituent flux, concentration, and human and environmental impacts. The sensitivity analysis can identify the key parameters that dominate overall uncertainty. Statistical methods used in SUM³ are based on the Monte Carlo sampling using the Latin Hypercube random numbers. The results file contains cumulative distribution function (CDF) data and can be graphically displayed through the FRAMES viewer option. 

SUM3 Users Guide includes a step-by-step process for setting up statistical analysis, running SUM³software, and interpreting results. Examples of input screens and result files are provided along with a full example case analysis.