A Southlake, Texas man charged with illegally injecting saltwater into a disposal well in North Dakota pled not guilty to federal charges last week in federal court.

Related:EPA Finds Little Risk to Drinking Water from Fracking

Jason Halek, a former operator of a saltwater well in southwest North Dakota, was indicted on 13 federal counts and fined a record $1.5 million in 2013 for putting drinking water at risk by illegally dumping more than 800,000 gallons of salty, oilfield wastewater into a former oil well in Stark County. He entered not guilty pleas to all charges including violating the Safe Drinking Water Act, making false statements and obstructing grand jury proceedings.

Saltwater is considered an environmental hazard that can easily kill vegetation. Companies commonly dispose of the oil production byproducts by injecting them into an approved underground facility.

The EPA has been working for years to analyze the available scientific data to determine whether fracturing for oil and gas changes the quality or quantity of drinking water resources. New findings, released June 6th, reveal  there are certain fracking activities that have the potential to impact drinking water resources including,

1. Water withdrawals in times of, or in areas with, low water availability
2. Spills of hydraulic fracturing fluids and produced water
3. Fracturing directly into underground drinking water resources
4. Below ground migration of liquids and gases
5. Inadequate treatment and discharge of wastewater