Sump sample trend plots are generated using dygraphs, an open-source JavaScript library that produces interactive charts of time series.

Internet Explorer does not play nice with dygraphs. It will work, but using a different browser is highly recommended.


Some basic instructions:

• Select a plot from the list above.
• Choose which locations to display by clicking on the checkboxes, or by using the "Select All" and "Select None" buttons.
• Hover the mouse over data points to see their values in the legend.
• Plots initially show data from the past five years; use the range selector below the plot to adjust the range of dates displayed.
• To move the date range, use the range selector to pan the plot, or click+drag the plot itself.
• Sometimes a location with only a single data point won't display when viewed by itself. Click+drag on the plot to get it to show up.
• To return to this page, click "Show Instructions" in the footer.

Note: In the case where ³H levels were measured to be less than some minimum value, the plot will display that value as rounded up to the nearest whole number. (For example, values of  "< 1.0" are displayed as "1.0" on the plot.)