|Abstract or Summary
- Produced water is a highly saline waste product of oil and gas production, which is generated in larger volumes than the hydrocarbons themselves in the United States. Spillage of produced water is of concern because its high salinity can contaminate soil, surface water and groundwater resources, and kill vegetation, including food crops. This study employed electromagnetic induction (EMI) to characterize the spatial variability of apparent electrical conductivity (ECa) as an indicator of soil salinity in three crop fields affected by produced water spills in Bottineau County, ND. EMI devices allow for relatively large areas of land to be accurately characterized in terms of apparent conductivity. Soil samples from the study area were tested for ECe (extract electrical conductivity), clay content, and pH to verify the presence of elevated salinity at the study sites. Spatial statistical analyses were employed to determine a potential causal relationship between ECa and the sources of produced water spills at the case study sites. Results of this study indicated elevated soil salinity at levels limiting to vegetation, and elevated ECa measurements clustering around oilfield infrastructure with levels three to ten times higher than background level, depending on the site. Implications for future studies include the development of ECa-guided soil sampling to compare the specific ions and strontium isotopes, if present, to those of the source formation’s produced water composition.