What does GeoSEM Do?
GeoSEM provides geospatial and traditional methods for estimating the exposure point concentration (EPC) for human and ecological risk assessment.
GeoSEM was selected by the EPA Office
of Superfund Remediation Technology Innovation to be included in the Decision Support Tool screening matrix. The report Decision Support Tools: Development of a Screening Matrix for 20 Specific Software Tools is also available from: http://www.frtr.gov/decisionsupport/.
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Why GeoSEM?
Produce more accurate estimates of the EPC: reduce bias that arises from judgmental sampling approaches (e.g., over-sampling areas that are known to have high concentrations of the contaminant).
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GeoSEM provides you with valid geospatial methods for assessing uncertainty in the EPC, regardless of the shape of the exposure unit, using ordinary kriging or simulation.
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Consistent with the EPA risk assessment paradigm: the EPC is estimated for the user-determined geographic area of interest (e.g., the exposure unit).

Risk is not calculated at points or individual grid cells (the latter are appropriate for describing spatial variability and uncertainty, but not for risk assessment).
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