Wastewater - also called saltwater or brine - is a common by product of oil and gas drilling. Wastewater spills are a common occurrence in North Dakota's oilfield. Inside Energy looked into state data to find out HOW common, and then used this analysis when the largest saltwater spill in state history occurred in January of 2015. We found that spills were on the increase, and that state officials regularly downplayed or misrepresented the spills. While oil spills generate headlines, wastewater spills are more devastating and can leave farmland sterile for generations.