Failed to respond to the second part of your statement.<quoted text>
"Has been found" means what?
Many water wells release hydrogen sulfide completely unrelated to any gas drilling activity.
Yes, it is true that some wells have methane and hydrogen sulfide in them unrelated to drilling activity.
However, if these substances do not normally appear in the ground water and appear only after fracking; I still think it should be up to the drilling company to pay for the clean-up.