Georeferenced pie charts provide information on the spatial distribution of the relative proportion of multiple constituents. The pie chart area can be scaled by the total concentration of these constituents to simultaneously relate the magnitude of the concentrations at these multiple locations.
To add a constituent, select it in the left control and hit the button with the right arrow to move it to the list of selected constituents. To remove a constituent from the list of selected constituents simply select the row and hit the button with the left-arrow.
The pie chart area for each location is based on the total concentration of the selected constituents at that location. EnviroInsite provides two options for how the areas are obtained. With the Scaled Areas option, the total concentration at each location is calculated and the area is then interpolated based on the total concentration between the specified area-concentration value pairs. For the Area Ranges option, the values are binned so that pie charts between specified ranges are assigned the user-specified value. Rows in the total-value / area table may be deleted by selecting the row header and hitting the delete button.