A performance‐based indicator chemical framework for potable reuse

Abstract

Many organic chemicals occur in reclaimed water at higher concentrations than in conventional drinking water sources. Some of these chemicals are known to occur at concentrations that pose chronic health risks. The toxicity or occurrence of other chemicals may not yet be known. Thus, potable reuse systems should achieve robust removal of known and unknown chemicals to ensure public health protection. Here, criteria were proposed for performance‐based indicators that could cost‐effectively verify this robust removal. The selection process was then demonstrated for a hypothetical system using ozonation, granular activated carbon, and direct ultraviolet photolysis. A set of indicators (e.g., acesulfame, meprobamate, perfluoroheptanoic acid, sucralose, iopromide, benzotriazole, and iohexol) was recommended on the basis of original and literature review data. However, the concentrations of some of these indicators are sufficient at certain locations only or decrease over time. Thus, indicators should be site‐specific, periodically reevaluated, and the topic of further research.

Granular activated carbon‐based treatment and mobility of per‐ and polyfluoroalkyl substances in potable reuse for aquifer recharge

“…However, because it is complicated and often cost prohibitive to monitor for every potential CEC, many researchers have suggested a variety of performance‐based indicator compounds to serve as proxies for removal of a broader suite of compounds, including PFAS (e.g. Schimmoller et al, 2019; Thompson & Dickenson, 2020). A recent Water Research Foundation report recommended that non‐RO reuse treatment trains should verify greater than 75% removal of sulfamethoxazole, iohexol, and sucralose across the entire treatment train to ensure adequate treatment of CECs (Schimmoller et al, 2019).…”

Introduction to the topical collection on potable reuse

“…The studies in this topical collection on potable reuse, along with other literature and operating history, demonstrate that advanced treatment processes are capable of meeting water quality objectives that produce safe water; however, this depends on the ability to quickly detect and respond to failures or loss of treatment efficiency, so monitoring and process control are key factors in a successful potable reuse system. Thompson and Dickenson (2020) developed criteria for performance-based indicators (PBIs) and proposed a list of specific chemical constituents that could serve as PBIs to monitor the effectiveness of ozone, GAC, and AOP. Walker, Boyle, Stanford, Owen, and Biscardi (2020) applied the principles of the hazard analysis and critical control point methodology and performed a full-scale failure analysis on the critical control points for membrane filtration and RO processes.…”