How can fracking impact water quality?

Fracturing fluids such as return fluids represent a potential risk to groundwater and surface water, due to the existing connection with

aquifera recharge zones.

During drilling in the fracking it is possible that there is water contamination due to accidental spillages of contaminants, for example in the process of cementing the casing or integrity problems of the casing may result

in the migration of thermogenic methane gas into the water.

Another source of contamination arises from the possibility that a hydraulic fracture is connected to the surface, since a fracture hydraulic can intercept a natural fracture for example a geological fault

When fracturing substance migration can be promoted toxic substances present in the subsoil, such as mercury, radio, lead and arsenic, which may increase the occurrence of chemical reactions and the creation of new polluting substances.

from what i read! use own words

Explanation:

Fracking can contaminate water supplies if it is not done properly, because the fracking fluid injected into rock to enable gas to be released often contains chemicals ... The other possibility of pollution is when the water, which is mixed with chemicals and sand for the fracking process, comes back to the surface

Does fracking contaminate water?

No. They gave examples where fracking could contaminate water. For instance they state that "Injection of hydraulic fracturing fluids directly into groundwater resources" can cause contamination ... The EPA also notes that disposing of fracking wastewater directly into surface water could contaminate drinking water.