Produced water in the Western United States: Geographical distribution, occurrence, and composition

Coproduced water is a byproduct of oil and natural gas production. Because it is in contact with hydrocarbon products and geologic formations in underground basins, it usually contains elevated concentrations of inorganic and organic constituents. This paper aims to illustrate the concentration ranges for specific contaminants and the estimated quantity of coproduced water in the Western United States. The total dissolved solids (TDS) concentration in coproduced water can vary between 1,000 mg/L and over 400,000 mg/L; however, some basins tend to have much lower median values of TDS. Sodium chloride was found to be most dominant salt found in coproduced water across all basins studied. Oil and grease, ethyl benzene, benzene, phenols, and toluene are the most common organic contaminants found in coproduced water. The total oil content in coproduced water can range from 40 mg/L to 2,000 mg/L. Understanding the composition and quantity of coproduced water is essential for assessing the viability of beneficial reuse and selecting appropriate treatment processes for the water.