The Energy Policy Institute at the University of Chicago has released a study in January, 2023, titled Internalizing Externalities: Disclosure Regulation for Hydraulic Fracturing, Drilling Activity and Water Quality by Pietro Bonetti, Christian Leuz, and Giovanna Michelon. This rather opaque title refers to a study performed to gauge the efficacy of mandating targeted transparency with hydraulic fracturing (HF).

For the study the authors used 4 ions considered signatures of HF-related activity- chloride, bromide, barium and strontium. These ions were considered the likely mode of detection if and when surface waters were affected. They are usually found in high concentration in flowback and produced water from HF wells and are considered signatures.

Some vocabulary-

Environmental externalities– the negative consequences on nature and biodiversity that result from human activity. (Google)

Internalities– An internality at the organizational level (an “organizational internality”) is the product of organizational practice, which part or all of an organization engages in that produces a cost or benefit within the organization, which is not considered when engaging in that practice.

Produced water– Produced water is composed of formation water, hydrocarbons, and fluids introduced during drilling.

Some Key Findings-

• “Significant improvements were found in water quality based on signature salts after mandates are introduced.”
• “After disclosure mandates, operators pollute less per unit of production, use fewer toxic chemicals, and cause fewer spills and leaks of HF fluids and wastewater.”
• They “… show that disclosure enables public pressure and that this pressure facilitates internalization“.

Barium is injected into oil and gas wells in the form of barite (BaSO4) to densify the drilling fluid although ilmenite (FeTiO3) has been used as well.

The barium we can account for as being from the barite in the drilling fluid. But what about the strontium? A USGS article titled “Use of Strontium Isotopes to Detect Produced-Water Contamination in Surface Water and Groundwater in the Williston Basin, Northeastern Montana“

“Produced waters typically have large ionic strengths including large Sr concentrations compared to surface water and shallow groundwater. If the Sr isotopic compositions of produced waters differ substantially from surface water and groundwater, then the Sr ratios could be a valuable and sensitive indicator of small amounts of contamination from produced water.“

The strontium isotopic ratio (87Sr/86Sr) can be an indicator of produced water contamination in surface water.