EPA Online Tools for Site Assessment Calculation
Module Home Objectives Table of Contents Previous < Next > 
1 of 6 
The OnSite calculators have a variety of applications, some of which are listed below. Briefly, the models for transport from fuel or pulse sources are highly selfcontained. All required inputs and necessary databases are directly linked to these calculators. Many of the components of the models, however, are available as separate calculators which can be used for planning site investigations, preparing model input parameters, for reviewing modeling reports, or for assessing contaminant impacts at sites.
The following lists common uses for the models and components.
 Planning Site Investigations

 Scale the Hydraulic Gradient from a water table map.
 Determine the travel time to determine where a monitor well should be placed.
 Evaluate the prospects for plume diving in order to place well screens at the appropriate depth.
 Model transport from a leaking underground storage tank to see how far contaminants might have traveled since the release date.
 Preparation of Model Input Data/Reviewing Modeling Reports
 Inputs for models are developed from sitespecific data, literature values, estimation formulas and other sources. OnSite calculators are available for a variety of common input parameters.
 Estimate the Hydraulic Gradient from heads at three locations.
 Convert a Henry's Law from the units of atm/mole K to the dimensionless equivalent, or estimate the temperaturedependent Henry's Law coefficient
 Compare retardation factors for different chemicals.
 Review an estimate of longitudinal dispersivity used in a model.
 Convert a first order rate constant to a half life.
 Determine the number of days between two sampling dates.
 Assessing the Impacts of Contamination at a Site

 Review the distribution of mass when a fuel is present in the subsurface.
 Determine the travel time to a sensitive receptor.
 Estimate the age of a release from the highest contaminant concentration observed at a site using the effective solubility calculator.
 Model transport from a leaking underground storage tank.
Home  Glossary  Notation  Links  References  Calculators 