Grantee Research Project Results
Protecting Water Quality during Enhanced Aquifer Recharge: A Geochemical Compatibility Assessment of Various Water Sources and Co-located Aquifers in the United States
EPA Grant Number: R840617Title: Protecting Water Quality during Enhanced Aquifer Recharge: A Geochemical Compatibility Assessment of Various Water Sources and Co-located Aquifers in the United States
Investigators: Fakhreddine, Sarah , Dahlke, Helen , Scanlon, Bridget R
Institution: Carnegie Mellon University , The University of Texas at Austin , University of California - Davis
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 2023 through September 30, 2026
Project Amount: $1,845,583
RFA: Enhanced Aquifer Recharge Performance and Potential Risk in Different Regional and Hydrogeologic Settings Request For Applications (RFA) (2023) RFA Text | Recipients Lists
Research Category: Endocrine Disruptors , Aquifer , Aquifer Recharge , Clean Water
Objective:
We seek to increase adoption of enhanced aquifer recharge (EAR) by better understanding the potential mobilization of geogenic and anthropogenic contaminants in key aquifers across the US. We focus on metal(loid)s, nutrients, salts, and pesticides which pose a particular threat to water quality due to their abundance in soils and sediments and complex geochemical interactions during EAR that control the mobility of these contaminants. Specific objectives include: (1) conduct a novel, national site-suitability study focused on assessing geochemical compatibility of various water sources, most notably excess surface water and treated wastewater, with co-located aquifers and (2) translate findings into actionable guidance on project siting, design (e.g., pretreatment), and operations (e.g., monitoring) to reduce the risk of contaminant mobilization. We hypothesize that the risk of contaminant mobilization from aquifer solids to groundwater, resulting from geochemical perturbations in the subsurface caused by EAR, varies spatially across the US and is primarily controlled by local constraints on the availability and quality of water sources for EAR and ambient geochemistry of co-located aquifers.
Approach:
We will leverage a large body of publicly available data, including EPA, USGS, and state databases, to assess geochemical compatibility during EAR. Much of our analysis will focus on the use of excess surface water for EAR but also include the potential use of locally available wastewater discharges. We will evaluate ambient geochemical conditions (e.g., redox, pH, ionic composition) in highly productive principal aquifers across the US of various lithologies. By combining source water and groundwater quality information, we will develop a geochemical compatibility score to inform risk assessment and safe EAR implementation that limits contaminant mobilization, particularly arsenic, nitrate, manganese, and/or uranium. To support our national analysis, we will synthesize detailed case studies of existing EAR sites in different regional and operational settings. Given the team’s diverse expertise in EAR and ongoing projects, we will leverage existing relationships with interested parties to better understand EAR uses and risks to inform guidance for EAR siting, design, and operations to protect water quality.
Expected Results:
This work will provide a quantitative understanding of the risks of geogenic and anthropogenic contaminant mobilization based on geographically varying constraints related to available water sources, aquifer characteristics, and EAR end uses. Primary outputs will be: (1) a technical report with an accompanying guidance document including case studies for water managers, regulators, and other stakeholders, and (2) an interactive web-map tool. Peer-reviewed publications and engagement with interested parties will take place throughout the project.
Publications and Presentations:
Publications have been submitted on this project: View all 5 publications for this projectSupplemental Keywords:
Managed aquifer recharge, aquifer storage and recovery, reuse, infiltration, injection, screening tool, stormwater, sustainable management, water resourcesProgress and Final Reports:
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.