A water contaminant is a substance which is found in water that has the potential to pose a risk to public health at certain levels. Some contaminants occur naturally in the environment and seep into water sources through erosion. Unfortunately, many of the contaminants found in water are a result of human activities. The industrial wastes from factories, refineries, mines and mills all contain harmful substances which can contaminate water sources.
Hydraulic fracturing, or fracking, is the procedure of creating fractures in shale, coalbed and tight-sand formations by injecting fluid (such as water, oil, or propane) into cracks to force them further open. This enlarges fissures which allow more oil and gas (methane) to flow out of the rock and into the wellbore. From there, the oil and gas can be extracted.