The Challenges and Opportunities of Beneficially Reusing Produced Water

Abstract

Water has always been an integral part of oil and gas exploration.  The expansion of hydraulic fracturing in the early 2000s greatly increased water usage and raised concerns about water demand and subsequent disposal.  Produced water, the largest byproduct of oil and gas production, includes water, injected fluids, and a mix of up to 600 chemicals used in production operations.  Historically, the common disposal practice was deep injection wells, which removes the water from the water cycle; however, reductions in storage capacity and increased incidence of earthquakes at a time when fresh water is increasingly scarce are shifting the conversation towards opportunities to beneficially reuse the water.

The widespread reuse of produced water is restricted by many factors, including limitations on availability, quantity, technical understanding, and regulation. Significant gaps in the current knowledge of the pollutants of concern present in produced water and the potential public health and environmental risks related to its release create challenges in designing appropriate treatment and permitting programs. 

The potential usefulness of produced water is highly regional and depends on the desired beneficial reuse. All forms of beneficial reuse of produced water require some level of treatment and risk exposure levels vary depending on the recipient. As policy-makers across the United States consider the viability of produced water in the context of land application for uses including rangeland rehabilitation and irrigation of non-food and food crops, more focus is needed to develop protective regulatory programs capable of managing an expansion of this practice.   This article explains the limitations and risks of reusing produced water, reviews federal and state laws that might be implicated in various beneficial reuse scenarios, and provides regulatory and nonregulatory recommendations to assist states considering water reuse to protect human health and the environment.

Keywords: produced water, groundwater recharge, water quality, clean water act