It should be easily detected with widely available and simple technology;
It should be present in concentrations well above background concentrations of
the same constituent in the natural system that is being studied; and
It should not modify the hydraulic conductivity or other properties of the
medium being studied.
Three classes of water tracing agents are available:
flora and fauna, principally micro organisms
ions in solution
natural pulses of discharge, solutes and sediment
artificially generated pulses
radiometrically detectable substances
Artificial fluorescent dyes are the principal and most successful water tracers for
conduit flow aquifers at the present time. Dyes are injected intentionally into ground water
for the purpose of tracing the movement of fluids in active ground water systems. Under
ideal circumstances, dyes can be injected into a perennial sinking stream on the facility site.
If a stream is not available, tank trucks of water and dye can be injected at the following sites
in a karst terrane, listed in decreasing order of desirability:
Sinkhole with a hole at its bottom.
Sinkhole without a hole at its bottom; excavation may reveal a hole that can be
Losing stream reach with intermittent flow.
Class V stormwater drainage well.
Well drilled on a fracture trace or a fracture trace intersection.