Kenneth C. Carroll

New Mexico State University | NMSU

A meta-analysis was conducted of published literature reporting concentrations of per- and polyfluoroalkyl substances (PFAS) in groundwater for sites distributed in 21 countries across the globe. Data for >35 PFAS were aggregated from 96 reports published from 1999 to 2021. The final data set comprised approximately 21,000 data points after removal...

Hyporheic exchange in streams is critical to ecosystem functions such as nutrient cycling along river corridors, especially for slowly moving or small stream systems. The transient storage model (TSM) has been widely used for modeling of hyporheic exchange. TSM calibration, for hyporheic exchange, is typically used to estimate four parameters, incl...

In the current era of rapid environmental changes, more rivers are projected to dry up and transition to disconnected systems in unprecedented duration and frequency. However, river-groundwater interactions, including connectivity, remain a challenge to characterize, especially for managed-ephemeral rivers such as the lower Rio Grande in southern N...

Perfluorooctane sulfonic acid (PFOS) is one of the most common per- and polyfluoroalkyl substances (PFAS) and is a significant risk driver for these emerging contaminants of concern. A series of two-dimensional flow cell experiments was conducted to investigate the impact of flow field heterogeneity on the transport, attenuation, and mass removal o...

Hyporheic zones are commonly regarded as resilient and enduring interfaces between groundwater and surface water in river corridors. In particular, bedform‐induced advective pumping hyporheic exchange (bedform‐induced exchange) is often perceived as a relatively persistent mechanism in natural river systems driving water, solutes, and energy exchan...

The Groundwater Module within the Sustainability Nexus Analytics, Informatics, and Data (AID) Programme of the United Nations University (UNU) addresses critical challenges in sustainable groundwater management. Groundwater resources around the world are under increasing stress from overextraction and pollution, threatening water and food security...

A self‐potential (SP) data‐inversion algorithm was developed and tested on an analytical model of electrical‐potential profile data attributed to single and multiple polarized electrical sources. The developed algorithm was then validated by an application to SP‐monitoring field data measured on the floodplain of East Fork Poplar Creek, Oak Ridge,...

Uranium (U) waste, generated at a variety of mines and nuclear production sites, migrates in the subsurface, posing a serious threat to contaminate groundwater systems. In this study, batch equilibrium and kinetic experiments , geochemical modeling and solid phase characterization were conducted to investigate the impact of Cr(VI), a common co-cont...

Understanding the intermittent hydraulic connectivity between ephemeral streams and alluvial aquifers is a key challenge for managing water resources in arid environments. The lower Rio Grande flows for short, discontinuous periods during the irrigation season through the Mesilla Basin in southeastern New Mexico and southwestern Texas. Hydraulic co...

Physically based hydrologic models require significant effort and extensive information for development, calibration, and validation. The study explored the use of the random forest regression (RFR), a supervised machine learning (ML) model, as an alternative to the physically based Soil and Water Assessment Tool (SWAT) for predicting streamflow in...

The rapid development of the unconventional oil and gas industry has promoted economic growth in the southwestern region of the United States. One of the major barriers for using treated produced water as an alternative water source is the lack of a comprehensive assessment of produced water quality and environmental toxicity. In this study, we emp...

In the current era of rapid environmental changes, more rivers are projected to dry up and transition to disconnected systems in unprecedented duration and frequency. However, surface-groundwater interactions including connectivity remain a challenge to characterize, especially for managed-ephemeral rivers such as the lower Rio Grande in southern N...

Understanding the intermittent hydraulic connectivity between ephemeral streams and alluvial aquifers is a key challenge for managing water resources in arid environments. The lower Rio Grande flows for short, discontinuous periods during the irrigation season through the Mesilla Basin in southeastern New Mexico and southwestern Texas. Hydraulic co...

A multimethod geoelectric survey was implemented between January and March 2022 along a 220-m long reach of the bedrock-lined streambed of East Fork Poplar Creek in Oak Ridge, Tennessee to identify locations of surface-water and groundwater exchange and characterize the subsurface flow paths that convey water between the stream and flood plain. A w...

We are developing a data-driven and machine learning-facilitated transformation of how we craft one-dimensional models for solute transport in rivers. After testing state-of-the-art 1-D models with hundreds of tracer tests performed worldwide, research has consistently shown that our current solute transport theory in river corridors misbehaves cat...

Cadmium (Cd) is a common toxic heavy metal in the environment. Taking Cd(II) as a target contaminant, we systematically compared the performances of three Fe-based nanomaterials (nano zero valent iron, nZVI; sulfidated nZVI, S-nZVI; and nano FeS, nFeS) for Cd immobilization under anaerobic conditions. Effects of nanomaterials doses, initial pH, co-...

The adsorption behaviors of ciprofloxacin (CIP), a fluoroquinolone antibiotic, onto goethite (Gt) in the presence of silver and titanium dioxide nanoparticles (AgNPs and TiO2NPs) were investigated. Results showed that CIP adsorption kinetics in Gt with or without NPs both followed the pseudo-second-order kinetic model. The presence of AgNPs or TiO2...

The data in this report are associated with “Characterization of Produced Water and Surrounding Surface Water in the Permian Basin, the United States” (Jiang et al. 2022) and include raw data on produced water (PW) quality and Pecos River water quality in the Permian Basin, which is one of the major oil and gas producing areas in the U.S. The data...

The quick development of novel water treatment techniques evaluates the mechanisms as a challenge in various systems. The participation of radical and non-radical mechanisms in the degradation of trichloroethane (TCA) in peroxymonosulfate (PMS) activated systems was demonstrated using synthetic catalysts. Various analytical characterizations repres...

A thorough understanding of produced water (PW) quality is critical to advance the knowledge and tools for effective PW management, treatment, risk assessment, and feasibility for beneficial reuse outside the oil and gas industry. This study provides the first step to better understand PW quality to develop beneficial reuse programs that are protec...

Produced water (PW) is a hypersaline waste stream generated from the shale oil and gas industry, consisting of numerous anthropogenic and geogenic compounds. Despite prior geochemical characterization, the comprehensive toxicity assessment is lacking for evaluating treatment technologies and the beneficial use of PW. In this study, a suite of in vi...

Synthesizing binational data to characterize shared water resources is critical to informing binational management. This work uses binational hydrogeology and water resource data in the Mesilla/Conejos-Médanos Basin (Basin) to describe the hydrologic conceptual model and identify potential research that could help inform sustainable management. The...

Measuring surface water temperature spatial variability is needed to estimate the interaction between surface water and groundwater, evaluate fish habitat and thermal inertia, and to estimate streamflow frequency and duration. Fiber optic distributed temperature sensing (FO-DTS) has been used in rivers and lakes, providing high-resolution and sensi...

2,4-Dichlorophenoxyl acetic acid (2,4-D), atrazine, glyphosate, and metribuzine, have been used extensively as herbicides, which can lead to contamination of soil and groundwater. The objective of this study was to quantify and compare the sorption and solute transport of these commonly used herbicides in alkaline agricultural soil since there is l...

PFAS and Cr are present at some sites as co-contaminants. The objective of this research was to investigate the co-transport behavior of per- and polyfluoroalkyl substances (PFAS) and hexavalent chromium (Cr(VI)) in porous media. Miscible-displacement experiments were conducted using two soils and an aquifer sediment with different geochemical prop...

Appropriate produced water (PW) management is critical for oil and gas industry. Understanding PW quantity and quality trends for one well or all similar wells in one region would significantly assist operators, regulators, and water treatment/disposal companies in optimizing PW management. In this research, historical PW quantity and quality data...

Spatial geostatistical interpolation of point measurements of streambed attributes in the hyporheic zone may be constrained by the anisotropy of the channel width to length ratio as well as sediment deposition anisotropy, and data density and spatial distribution significantly impact the results. Spatial clustering and low spatial data density can...

The shallow (<15 m depth) subsurface environment of a short reach along a bedrock stream was investigated with electrical resistivity and induced polarization (IP) to map details of bedrock and soil sediments. The bedrock is mostly comprised of limestone, and is generally resistive compared to the overlying soil. The soil-bedrock interface was dete...

The objectives of this research were to examine the transport of perfluorooctane sulfonic acid (PFOS) in aquifer sediment comprising different geochemical properties, and to compare the behavior to that observed for PFOS transport in soil and sand. PFOS retardation was relatively low for transport in all media. The PFOS breakthrough curves were asy...

Fluoride (F) contamination is widely distributed due to natural or anthropogenic causes. A series of mesoporous goethite (α-FeOOH) were synthesized by hydrothermal treatment for rapid F removal from water. The morphology of adsorbents was found to be controlled by varying the hydrothermal and calcination conditions. A highly crystallized FeOOH can...

A significantly elevated groundwater salinity zone was identified in the southern part of the Mesilla Valley. This investigation characterized the occurrence, spatial extent, and source of the plume of elevated groundwater salinity using a wide range of geochemical and geophysical data and methods.

Mountain-front recharge (MFR), or all inflow to a basin-fill aquifer with its source in the mountain block, is an important component of recharge to basin-fill aquifer systems. Distinguishing and quantifying the surface from subsurface components of MFR is necessary for water resource planning and management, particularly as climate change may impa...

Persulfate (PS) is widely used to degrade emerging organic contaminants in groundwater and soil systems, and various PS activation methods (e.g., energy or chemical inputs) have been considered to increase oxidation strength. This study investigates PS activation through manganese amendment in the form of potassium permanganate (KMnO 4) and mangane...

The objective of this study is to compare the consistency between column and batch experiment methods for measuring solid-phase sorption coefficients and isotherms for per and polyfluoroalkyl substances (PFAS). Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are used as representative PFAS, and experiments are conducted with...

Agricultural and environmental scientists collaborated with educational technology researchers to create multimedia learning tools to fill gaps in student understanding of key concepts that undergraduates often struggle with, including sorption, cation exchange capacity, inner and outer sphere bonding, and soil system complexity. These resources ar...

A Monitored Natural Attenuation (MNA) assessment approach typically used for contaminant remediation feasibility assessment was developed here for remediation-reagent delivery assessment. Subsurface delivery of oxidants, such as aqueous ozone (O3) for in situ chemical oxidation (ISCO) of groundwater contaminants, is naturally attenuated by oxidant...

Interest in both environmental impact and potential beneficial uses of produced water (PW) has increased with growth in unconventional oil and gas production, especially in semi-arid regions, e.g. the Permian Basin, the most productive tight-oil region in the USA. Characterization of PW compositional variability is needed to evaluate environmental...

The objective of this research was to examine the influence of nonideal sorption/desorption on the transport of polyfluorinated alkyl substances (PFASs) in soil, with a specific focus on characterizing and quantifying potential extended, mass-transfer-limited elution behavior. Perfluorooctane sulfonic acid (PFOS) was used as a representative PFAS,...

The physics of disconnection between interrelated surface and groundwater has evolved considerably in recent years, especially since conjunctive use of water resources is increasingly dependent on groundwater resilience, but methods to measure disconnection on a river basin scale are lacking especially for managed‐ephemeral and irrigated‐agricultur...

Solvent stabilizer 1,4-dioxane, an emerging recalcitrant groundwater contaminant, was commonly added to chlorinated solvents such as trichloroethene (TCE), and the impact of co-disposal on contaminant transport processes remains uncertain. A series of batch equilibrium experiments was conducted with variations of 1,4-dioxane and TCE composition to...

Final Report for SERDP (DoD) Project ER-2302.

Enhanced reactivity of aqueous ozone (O3) with hydroxypropyl-β-cyclodextrin (HPβCD) and its impact on relative reactivity of O3 with contaminants were evaluated herein. Oxidation kinetics of 1,4-dioxane, trichloroethylene (TCE), and 1,1,1-trichloroethane (TCA) using O3 in single and multiple contaminant systems, with and without HPβCD, were quantif...

63rd Annual New Mexico Water Conference organized by WRRI, NM

A comprehensive compartment model is presented for PFAS retention that incorporates all potential processes relevant for transport in source zones. Miscible-displacement experiments were conducted to investigate separately the impact of adsorption at the air-water and decane-water interfaces on PFAS retention and transport. Two porous media were us...

The concept of the Borehole Diffusive Flux Apparatus (BDFA) is presented herein. The BDFA is an innovative apparatus designed to provide continuous direct access to an undisturbed column of sediment that can be monitored at multiple discrete vertical intervals to provide high-resolution characterization of local-scale mass transfer and attenuation....

Manned spaceflight outside of low-Earth orbit requires significant advances in closed-loop life support systems, especially the recycling of solid and liquid wastes to produce oxygen, food, and fresh water. Here, moderate temperature (400–600 °C) slow pyrolysis was tested to transform a high-fidelity spacecraft solid waste simulant into nutrient-ri...

The Rincon Valley in arid, south-central New Mexico, is especially impacted by reduced surface water supply because the contribution of groundwater is limited by aquifer constraints. Consecutive surface water allotment shortages in the Elephant Butte Irrigation District (EBID) have reduced recharge. The effects are compounded by farmers continuing...

Recalcitrant organic contaminants, such as 1,4-dioxane, typically require advanced oxidation process (AOP) oxidants, such as ozone (O3), for their complete mineralization during water treatment. Unfortunately, the use of AOPs can be limited by these oxidants' relatively high reactivities and short half-lives. These drawbacks can be minimized by par...

Recalcitrant organic groundwater contaminants, such as 1,4-dioxane, may require strong oxidants for complete mineralization. However, their efficacy for in-situ chemical oxidation (ISCO) is limited by oxidant decay and reactivity. Hydroxypropyl-β-cyclodextrin (HPβCD) was examined for its ability to stabilize aqueous phase ozone (O3) and prolong oxi...

https://nmwrri.nmsu.edu/wp-content/uploads/2016/Research/swra-2015-16/Cruz-FinalReport.pdf

We evaluated three types of functionalized, graphene-based materials for activating persulfate (PS) and removing (i.e., sorption and oxidation) sulfamethoxazole (SMX) as a model emerging contaminant. Although advanced oxidative water treatment requires PS activation, activation requires energy or chemical inputs, and toxic substances are contained...

Two different methods are currently used for measuring interfacial areas between immiscible fluids within 3-D porous media, high-resolution microtomographic imaging and interfacial partitioning tracer tests (IPTT). Both methods were used in this study to measure nonwetting/wetting interfacial areas for a natural sand. The microtomographic imaging w...

Despite being one of the most important oil producing provinces in the United States, information on basinal hydrogeology and fluid flow in the Permian Basin of Texas and New Mexico is lacking. The source and geochemistry of brines from the basin were investigated (Ordovician- to Guadalupian-age reservoirs) by combining previously published data fr...

Cost-effective creation of high-permeability reservoirs inside deep crystalline bedrock is the primary challenge for the feasibility of enhanced geothermal systems (EGS). Current reservoir stimulation entails adverse environmental impacts and substantial economic costs due to the utilization of large volumes of water "doped" with chemicals includin...

Multiphase-fluid distribution and flow is inherent in numerous areas of hydrology. Yet, pore-scale characterization of transitions between two and three immiscible-fluids is limited. The objective of this study was to examine the impact of such transitions on the pore-scale configuration of organic liquid in a multi-fluid system comprising natural...

This textbook integrates classic principles of flow through porous media with recently developed stochastic analyses to provide new insight on subsurface hydrology. Importantly, each of the authors has extensive experience in both academia and the world of applied groundwater hydrology. The book not only presents theories but also emphasizes their...

Cost-effective and safe creation of high-permeability reservoirs inside deep crystalline bedrock is the primary challenge for the application of enhanced geothermal systems (EGS). Current reservoir stimulation processes entail adverse environmental impacts and substantial economic costs due to the utilization of extremely large volumes of water and...

Cost-effective yet safe creation of high-permeability reservoirs within deep bedrock is the primary challenge for the viability of enhanced geothermal systems (EGS) and unconventional oil/gas recovery. Although fracturing fluids are commonly used for oil/gas, standard fracturing methods are not developed or proven for EGS temperatures and pressures...

The purpose of this study is to examine the development and effectiveness of a persistent dissolved-phase treatment zone, created by injecting potassium permanganate solution, for mitigating discharge of contaminant from a source zone located in a relatively deep, low-permeability formation. A localized 1,1-dichloroethene (DCE) source zone comprisi...