Maybe someone could patent a tracking fracking fluid.
A fracking lawsuit is going on in Canada, with a legal filing stating
“As a result, Ms. Ernst’s water is now so contaminated with methane and other chemicals that it can be lit on fire,” said the legal statement.
In 2008, an Alberta Research Council report concluded the methane found in the wells in the area was naturally occurring
So, this one might not go far, depending on how the expert testimony goes. Still, it adds to a simple solution to future fracking issues: add tracers to fracking fluids. A miniscule amount of a radioisotope, or some D2O (D = deuterium), or something. A good fracking company would I think jump at the chance to do this.