Substances In Groundwater Research Articles

Metamodel for Groundwater Leaching Assessment in Europe.

Under Regulation (EC) 1107/2009, FOCUS leaching models forecast the concentration of plant protection product (PPP) active substances in groundwater, known as the predicted environmental concentration (PECGW), based on parameters like DT50, KOC, and application rate. This study used simulated PECGW from PEARL and PELMO for training with over 870 combinations of KOC and DT50 across 174 different crop-location-software scenarios. Generalized additive models (GAMs) were trained on these simulations, achieving 96-99% accuracy for in-sample and out-of-sample validation, comparing the predicted environmental concentration in GAM (PECGAM) with the simulated PECGW relative to the 0.1 μg/L regulatory limit. Our GAM approach offers rapid PEC calculations for numerous substances across 174 scenarios, significantly accelerating early-stage molecule development analogue selection.

Nanotechnology advancements in groundwater remediation: A comprehensive analysis of current research and future prospects

Groundwater contamination is a critical environmental issue with vital health implications. This review evaluates the advancements in nanotechnology for groundwater remediation, highlighting major findings and their relevance to Sustainable Development Goals (SDGs). Key findings include the superior adsorption capabilities of multi-walled carbon nanotubes functionalized with various groups for removing heavy metals and aromatic pollutants, outperforming traditional sorbents. The review also discusses the potential of nanomaterials like zero-valent iron nanoparticles for effective contaminant degradation. Despite promising results in the studies, challenges such as the movement and dispersion of engineered nanomaterials in porous media and the need for innovative delivery methods are identified. Furthermore, this review explores the environmental and health risks associated with the use of nanomaterials, emphasizing the need for risk assessments to ensure safe application. The novel delivery methods assessed, such as the use of groundwater circulation wells and the combination of nanoremediation with other techniques like bioremediation, demonstrate potential to enhance remediation efficiency. The integration of nanotechnology in groundwater remediation directly contributes to Clean Water and Sanitation by providing innovative solutions for the purification of water resources. Advanced nanomaterials not only improve contaminant removal efficiency but also promote sustainable water management practices. Additionally, the environmental benefits align with Life on Land, as the reduction of hazardous substances in groundwater protects terrestrial ecosystems and promotes biodiversity conservation. This review study aims to enhance understanding and identify future opportunities for nanotechnology in groundwater remediation. By addressing current challenges and proposing innovative solutions, this review underscores the importance of interdisciplinary research and collaboration in advancing sustainable development.

DEVELOPMENT OF A MATHEMATICAL MODEL FOR ANALYSING THE HAZARDOUS IMPACT ON THE STATE OF GROUNDWATER IN CITY AGGLOMERATIONS FROM MISSILE AND ARTILLERY ATTACKS

The authors have developed a mathematical model for analysing the hazardous impact on the groundwater in urban agglomerations from missile and artillery attacks. The mathematical model consists of a system of four analytical dependencies. The first analytical dependence describes determining the area of groundwater intake from the groundwater level, considering the presence of artificial coatings, infiltration, evaporation, and transpiration, as well as the effect of evapotranspiration. The second dependence determines the area of influence of the missile and artillery danger from the type of weapon, the explosive charge, calibre (diameter), and territorial conditions, the key indicators of the content of which in the territory of the critical infrastructure object, which suffered damage, are further determined by expert calculation using natural samples of soils and groundwater. The third dependence determines the impact of harmful (polluting) substances on groundwater in the territory of the critical infrastructure object, which suffered damage, depending on the process of groundwater movement in the area of the emergency, taking into account the hydraulic pressure and water yield coefficient; the process of distribution of chemically dangerous substances in groundwater, taking into account the coefficient of hydrodynamic dispersion and the velocity of groundwater; convective diffusion of chemically hazardous substances, taking into account the kinetics of sorption. The fourth dependency allows us to choose an efficient concept for the organisation of groundwater monitoring on the territory of a critical infrastructure object that suffered damage based on the variation of formalised parameters for solving individual problems. The initial conditions of the mathematical model are related to the presence of chemically dangerous compounds in groundwater at the maximum permissible concentration level. The boundary conditions of the mathematical model relate to the non-overgrowth of consequences beyond the object level in terms of the number of victims. Keywords: mathematical model, groundwater, missile and artillery damage, critical infrastructure object, emergency prevention.

Forecasting health risks for the residents of Southern Russia through satellite and climate-based aridity indicators

BACKGROUND: The aridification of the Southern region of Russia will lead to a significant rise in the concentration of hazardous substances in groundwater over the long term. This phenomenon poses a serious threat to the environment and public health.
 AIM: To assess the potential of the multi-regression climate model in predicting the long-term health risks associated with the ingestion of toxic substances released from groundwater sources.
 METHODS: An assessment of non-carcinogenic health risks (HI) was conducted for the period 2017–2022, focusing on three groundwater basins in the Volgograd Trans-Volga region. The study involved the analysis of toxicant concentrations in 1149 water samples at the 95th percentile. NDMI and De Martonne Index (DMI) values were calculated based on modified data obtained through Land Surface Temperature (LST) satellite analysis. These indices were then employed as predictors in our models, with the HI serving as the dependent variable.
 RESULTS: A significant contribution of chloroform to the overall risk pattern for groundwater in the Volgograd Trans-Volga region was observed. The maximum values were recorded in the Nizhnevolzhskiy groundwater basin (HQchildren/chloroform=3.20, HQadults/chloroform=1.37) in 2017. The satellite aridity index NDMI makes the greatest contribution to the reliability of the predictive model of long-term health risk dynamics that shape the oral intake of pollutants from groundwater in the Volgograd Trans-Volga region. The lowest multiple regression value was noted for the health risk for adults (ry,x1,x2=–0.909, p=0.012) in the Severo-Prikaspiyskiy basin, the maximum was recorded in Ryn-Peskovsky basin for children (ry,x1,x2=–0.992, p=0.002). The DMI provides insignificant reliability in predicting long-term dynamics of non-carcinogenic health risks associated with toxicants circulating in arid ecosystems of the South of Russia. The greatest contribution of this predictor was observed for the health risk of children in the Ryn-Peskovsky basin (rx2/x1=–0.554, p=0.105).
 CONCLUSION: Our findings suggest a significant potential for integrating NDMI in monitoring the social and hygienic quality of underground water in arid zones of Southern Russia. The NDMI indicator has demonstrated high resolution and sensitivity to water quantity in steppe vegetation, reflecting its accuracy for arid topography. This integration holds promise for enhancing the monitoring and management of underground water resources in Southern Russia.

A high-throughput small volume matrix based calibration using isotope dilution liquid chromatography tandem mass spectrometry analysis for 42 per and polyfluoroalkyl substances in groundwater

A novel method for the determination of per- and polyfluoroalkyl substances (PFAS) in groundwater is presented using a subsample, matrix-matched calibrators, 96-well plate solid phase extraction (SPE), and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Accuracy, precision, measurement of uncertainty (MOU), method detection limit (MDL), method quantitation limit (MQL), analytical measurement range, interferences/ion suppression, and analyte stability were determined as part of the in-house method validation. The method quantitates 42 PFAS compounds from nine different compound classes. Accuracy for the reference material (RM) and matrix spike (MS) ranged from 52.3 to 117.8 %, and precision for the MS and matrix spike duplicate (MSD) had a coefficient of variation (CV) from 2.0 % to 23.3 %. MDLs spanned from 0.07 to 1.97 ng L−1, with MQLs ranging from 0.20 to 5.90 ng L−1. Suppression studies determined that iron and manganese have effects on analytes that do not have paired isotopically labeled standards. The results from the in-house validation indicated that this Michigan Department of Health and Human Services laboratory developed test meets the necessary accuracy, precision, MDL, MQL and reporting limits requirement established by the laboratory's quality system essentials (QSEs) and select criteria from the Department of Defense (DoD) Quality Systems Manual for Environmental Laboratories and American Industrial Hygiene Association Laboratory Accreditation Program, LLC (AIHA LAP, LLC) accrediting International Standard Organization (ISO/IEC 17025:2017) check list.

Treatment of poly‐ and perfluoroalkyl substances in groundwater using a carbon‐based micro‐adsorbent and ceramic membrane filtration

AbstractThis article presents the results of an Environmental Security Technology Certification Program (ESTCP) demonstration conducted at Horsham Air Guard Station and the former Willow Grove Naval Reserve Station in Horsham, Pennsylvania. The ESTCP project information can be found here: https://www.serdp-estcp.org/projects/details/568c0487-f182-40c1-9d4d-9297f4bbedda/er19-5181-projcet-overview. The technology demonstrated, identified as the AquaPRS™ system, employs a carbon‐based micro‐adsorbent suspension to adsorb polyfluoroalkylated substance (PFAS), which is subsequently filtered using a ceramic membrane filter. A prototypical AquaPRS system was specifically designed and implemented to treat per‐ and PFAS‐contaminated water resources at a fidelity level that could be replicated at other US Department of Defense sites. The objective of the project was to demonstrate and validate the application of the adsorption and separation treatment approach to reduce the total life‐cycle cost of treating PFAS‐impacted groundwater. The results of the demonstration showed that the AquaPRS technology provides an alternative to granular activated carbon (GAC) and ion exchange (IX) systems based on treatment efficacy and cost performance using lifecycle cost analyses. Pretreatment included cloth media filtration with a nominal 5 µm particulate rejection rating to remove sediment from the surface water treated during the Horsham evaluation. Prefiltration was not necessary for treating the Willow Grove groundwater due to the lower raw turbidities. The micro‐adsorbent was added to the system to maintain a suspension between 1 and 50 g/L in the sorbent chamber at reaction times from 5 to 20 min. Treated effluent was separated from the sorbent slurry matrix using the ceramic membrane filter, with the slurry returned to the sorption reactor. The first study conducted at Horsham Air Guard Station demonstrated and validated the AquaPRS treatment approach using a mobile pilot system, while the second study (conducted at the former Naval Reserve Air Station at Willow Grove) provided further optimization of cost, performance, and scalability. At Horsham, 13 tests were conducted over 9 months using a dual‐train pilot with each test evaluating two separate conditions. The first 10 tests were conducted with treatment systems in parallel and the remaining three were conducted in series. At Willow Grove, five tests were conducted over a 6‐month period for a total of 10 individual test conditions. Three tests were performed in parallel with two operated in series. Tests conducted at Horsham evaluated the performance of the AquaPRS system at different hydraulic detention times (5–120 min), sorbent mass (10–430 g), sorbent densities (0.5–40 g/L), and flowrates (0.1–1 L/min). At Willow Grove, the range of these parameters was further narrowed with hydraulic detention times from 10 to 20 min, sorbent mass from 100 to 200 g, sorbent density from 10 to 25 g/L, and flowrate from 0.67 to 1 L/min. AquaPRS was validated by quantifying the specific adsorption rate (SAR) of various PFASs on the micro‐adsorbent and comparing it to values derived for GAC and IX from the same water matrix. The costs of the three treatment systems were compared to estimate a payback period for the AquaPRS system compared to GAC and IX. At 10% breakthrough, the SAR of AquaPRS for the combined concentration of the United States Environmental Protection Agency's Third Unregulated Contaminant Monitoring Rule (UCMR3) PFASs was nearly 300 times higher compared to those treated with GAC. At 40 ng/L breakthrough for combined UCMR3 compounds, a single‐stage AquaPRS system at Horsham achieved 146 µg PFAS/g sorbent SAR, while a dual‐stage system at Willow Grove achieved 2128 µg PFAS/g sorbent. The AquaPRS system showed a breakeven period of 8 months compared to a similarly designed GAC system in the Horsham evaluation using the observed adsorption rates. In the Willow Grove test case, a 24–36‐month breakeven period was determined for the AquaPRS technology when compared to the highest sorption rates observed among five previously tested IX resins. The AquaPRS benefits in comparison to GAC/IX include effective performance in the presence of co‐contaminants, adaptability to changing conditions, limited downtime for sorbent replacement, resistance to biofouling, small footprint, and reduced disposal requirements. The lower waste production rates are due to the AquaPRS' ability to dewater the spent sorbent resulting in a waste generation of just 0.002% of the total volume of water treated. Based on the treatment efficacy and cost performance, the AquaPRS system is positioned as an alternative to GAC and IX systems.

Closing the gap: Ion chromatography coupled to high-resolution mass spectrometry to trace highly polar anionic substances in groundwater

Persistent, mobile and toxic (PMT), and very persistent and very mobile (vPvM) substances pose a threat to the water cycle but are often not covered in conventional environmental monitoring programs. Within this realm of substances, one compound class of concern are pesticides and their transformation products as they are deliberately introduced into the environment. To detect very polar anionic substances, including many pesticide transformation products with log DOW values ranging between −7.4 and 2.2, an ion chromatography high-resolution mass spectrometry method was developed in this study. Since inorganic anions, such as chloride and sulfate, interfere with the analysis of organic species, their removal via precipitation with Ba/Ag/H cartridges was assessed. To improve LOQs, vacuum-assisted evaporative concentration (VEC) was evaluated. By using VEC and removing inorganic salt ions, the median LOQ improved from 100 ng/L in evian® water without sample treatment to 10 ng/L after enrichment and 30 ng/L in karst groundwater. Using this method, twelve out of 64 substances covered by the final method were found in karst groundwater in concentrations of up to 5600 ng/L, and seven exceeded 100 ng/L. To the authors' knowledge, the dimethenamid TP M31 and chlorothalonil TP SYN548008 were detected for the first time in groundwater samples. The coupling to a high-resolution mass spectrometer also allows for non-target screening and hence, this method presents a powerful tool to tackle PMT/vPvM substances.

Per- and polyfluoroalkyl substances in groundwater in Thailand: occurrence, source identification and spatial distribution

Per- and polyfluoroalkyl substances have the potential to leach into groundwater, particularly in areas with potential pollution sources, such as landfills. The composition and distribution of per- and polyfluoroalkyl substances, as well as soil characteristics, are particularly useful for identifying the sources of per- and polyfluoroalkyl substances. The objectives of the present study were to characterise per- and polyfluoroalkyl substance levels in groundwater in Thailand, identify their potential sources and highlight their spatial distribution. Groundwater samples were collected in areas hosting municipal and industrial waste disposal sites. Seven Per- and polyfluoroalkyl substances were extracted from the groundwater samples using the solid-phase extraction technique and analysed by high-performance liquid chromatography-tandem mass spectrometry. These samples contain mostly perfluorooctanoic acid and perfluorooctane sulfonate, with the highest concentrations of 34.96 and 25.88 ng L–1, respectively, obtained from industrial waste disposal site areas. The presence of perfluorohexane sulfonate in most samples from industrial waste disposal site areas suggests its usage as a substitute for perfluorooctane sulfonate-based products. In addition to waste disposal, hierarchical cluster analysis reveals that other sources likely influence the presence of per- and polyfluoroalkyl substances in groundwater in Thailand. Livestock farming and ponds near groundwater wells probably impact per- and polyfluoroalkyl substances levels in the associated groundwater. The spatial distribution of per- and polyfluoroalkyl substances shows that in addition to waste disposal sources, soil characteristics and interactions between their negatively charged components and cations in soils significantly influence the contamination of groundwater in the areas studied.

Hydrogeochemical characterization and natural background level determination of selected inorganic substances in groundwater from a semi-confined aquifer in Midwestern Burkina Faso, West Africa.

Hydrogeochemical processes that govern selected inorganic substances distribution in a semi-confined aquifer were characterized using traditional hydrogeochemical approaches and natural background levels (NBLs). Saturation indices and bivariate plots were used to investigate the effects of water-rock interactions on natural evolution of the groundwater chemistry, whereas Q-mode hierarchical cluster analysis and one-way analysis of variance classified the groundwater samples into three distinct groups. To highlight the groundwater status, NBLs and threshold values (TVs) of the substances were calculated using pre-selection method. Piper's diagram showed that the Ca-Mg-HCO3 water type was the only hydrochemical facies of the groundwaters. Although all samples, except a borewell with a high NO3- concentration, had major ion and transition metal concentrations within the World Health Organization's recommended guideline values for drinking water, Cl-, NO3- and PO43- exhibited scattered distribution patterns, reflecting their nonpoint anthropogenic sources in the groundwater system. The bivariate and saturation indices revealed that silicate weathering and possible gypsum and anhydrite dissolution contributed to the groundwater chemistry. In contrast, NH4+, FeT and Mn abundance appeared to be influenced by redox conditions. Strong positive spatial correlations between pH, FeT, Mn and Zn suggested that mobility of these metals was controlled by pH. The relative high F- concentrations in lowland areas may imply the impact of evaporation on this ion's abundance. Contrary to TVs of HCO3-, those of Cl-, NO3-, SO42-, F- and NH4+ were below the guideline values, confirming the influence of chemical weathering on the groundwater chemistry. Based on the present findings, further studies that take into account more inorganic substances are required for NBLs and TVs determination in the area, thereby setting up a robust sustainable management plan for the regional groundwater resources.

Groundwater Quality and Health: Making the Invisible Visible.

Linking groundwater quality to health will make the invisible groundwater visible, but there are knowledge gaps to understand the linkage which requires cross-disciplinary convergent research. The substances in groundwater that are critical to health can be classified into five types according to the sources and characteristics: geogenic substances, biogenic elements, anthropogenic contaminants, emerging contaminants, and pathogens. The most intriguing questions are related to quantitative assessment of human health and ecological risks of exposure to the critical substances via natural or induced artificial groundwater discharge: What is the list of critical substances released from discharging groundwater, and what are the pathways of the receptors' exposure to the critical substances? How to quantify the flux of critical substances during groundwater discharge? What procedures can we follow to assess human health and ecological risks of groundwater discharge? Answering these questions is fundamental for humans to deal with the challenges of water security and health risks related to groundwater quality. This perspective provides recent progresses, knowledge gaps, and future trends in understanding the linkage between groundwater quality and health.

Toxicity of Chemical Substances in Groundwater of Jhunjhunu District of Rajasthan, India: A Physicochemical Analysis

Toxicity of Chemical Substances in Groundwater of Jhunjhunu District of Rajasthan, India: A Physicochemical Analysis

Iron-induced association between selenium and humic substances in groundwater from deep sedimentary formations

ABSTRACT To better understand the impact of natural organic matters (NOM) on facilitating 79Se migration in underground environments, the association mechanism between Se and humic substance (HS) in groundwater was investigated through incubation experiments using groundwater samples under abiotic and biotic conditions and speciation analyses using a DAX-8 resin isolation technique and a size exclusion chromatography (SEC) coupled online to ultraviolet–visible (UV–Vis) and inductively coupled plasma mass spectrometry (ICP-MS) detection (SEC-UV-ICP-MS). Selenite added into the groundwater was reduced to elemental Se only when microbial activity was stimulated by a nutrient. The DAX-8 resin isolation technique showed that Se associated with HS in both the oxidizing and reducing conditions, but the proportion of the associated Se to the total dissolved Se was the highest under the reducing condition. The SEC-UV-ICP-MS analyses of Se, Fe, and HS extracted from the DAX-8 resin showed that there is a fraction of Se that simultaneously elutes with Fe and HS. Logarithmic peak areas of Se and Fe associated with HS under the moderately oxidizing conditions were linearly correlated regardless of the presence of microorganisms and nutrient ( r = 0.947, p ≤ 0.01 with the addition of Se; r = 0.995, p < 0.01 without the addition of Se). The SEC chromatogram of Se associated with HS under the reducing condition was well-matched with those under the moderately oxidizing conditions. Therefore, these suggest that Fe-induced association between Se and HS can preferentially occur in the groundwater conditions.

Global distributions, source-type dependencies, and concentration ranges of per- and polyfluoroalkyl substances in groundwater

A meta-analysis was conducted of published literature reporting concentrations of per- and polyfluoroalkyl substances (PFAS) in groundwater for sites distributed in 20 countries across the globe. Data for >35 PFAS were aggregated from 96 reports published from 1999 to 2021. The final data set comprises approximately 21,000 data points after removal of time-series and duplicate samples as well as non-detects. The reported concentrations range over many orders of magnitude, from ng/L to mg/L levels. Distinct differences in concentration ranges are observed between sites located within or near sources versus those that are not. Perfluorooctanoic acid (PFOA), ranging from <0.03 ng/L to ~7 mg/L, and perfluorooctanesulfonic acid (PFOS), ranging from 0.01 ng/L to ~5 mg/L, were the two most reported PFAS. The highest PFAS concentration in groundwater is ~15 mg/L reported for the replacement-PFAS 6:2 fluorotelomer sulfonate (6:2 FTS). Maximum reported groundwater concentrations for PFOA and PFOS were compared to concentrations reported for soils, surface waters, marine waters, and precipitation. Soil concentrations are generally significantly higher than those reported for the other media. This accrues to soil being the primary entry point for PFAS release into the environment for many sites, as well as the generally significantly greater retention capacity of soil compared to the other media. The presence of PFAS has been reported for all media in all regions tested, including areas that are far removed from specific PFAS sources. This gives rise to the existence of a “background” concentration of PFAS that must be accounted for in both regional and site-specific risk assessments. The presence of this background is a reflection of the large-scale use of PFAS, their general recalcitrance, and the action of long-range transport processes that distribute PFAS across regional and global scales. This ubiquitous distribution has the potential to significantly impact the quality and availability of water resources in many regions. In addition, the pervasive presence of PFAS in the environment engenders concerns for impacts to ecosystem and human health.

Worst-case ranking of organic chemicals detected in groundwaters and surface waters in England

The Environment Agency has been using Gas Chromatography–Mass Spectrometry (GC–MS) and Accurate-mass Quadrupole Time-of-Flight (Q-TOF) / Liquid Chromatography-Mass Spectrometry (LC-MS) target screen analysis to semi-quantitatively measure organic substances in groundwater and surface water since 2009 for GC–MS and 2014 for LC-MS. Here we use this data to generate a worst-case “risk” ranking of the detected substances. Three sets of hazard values relating to effects on aquatic organisms, namely Water Framework Directive EQSs, NORMAN Network PNECs (hereafter NORMAN PNEC) and chronic Species Sensitivity Distribution (SSD) HC50s from Posthuma et al., (2019) were used for the assessment. These hazard values were compared to the highest measured concentration for each chemical to generate a worst-case hazard quotient (HQ). Calculated HQs for each metric were ranked, averaged and multiplied by rank for detection frequency to generate an overall ordering based on HQ and occurrence. This worst-case approach was then used to generate ranking lists for GC–MS and LC-MS detected substances in groundwater and surface water. Pesticides in the top 30 overall ranked list included more legacy pesticides in groundwater and more current use actives in surface water. Specific uses were linked to some high rankings (e.g. rotenone for invasive species control). A number of industrial and plastics associated chemicals were ranked highly in the groundwater dataset, while more personal care products and pharmaceuticals were highly ranked in surface waters. Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) compounds were commonly highly ranked in both environmental compartments. The approach confirmed high rankings for some substance (e.g. selected pesticides) from previous prioritization exercises, but also identified novel substance for consideration (e.g. some PFAS compounds and pharmaceuticals). Overall our approach provided a simple approach using readily accessible data to identify substances for further and more detailed assessment.

Study on Hydrogeochemical Characteristics of Deeply Buried Mining Area in Inner Mongolia-Shaanxi Province, China

Abstract This paper adopted organic components, environmental isotopes, and organic components to study water quality comprehensively, in order to distinguish the differences of hydrogeochemical characteristics between coal measure strata and aquifers on the roof of deeply buried mining areas in Inner Mongolia-Shaanxi, China. The results show that the deeply buried mining area in Inner Mongolia-Shaanxi belongs to Mu Us Desert, and the surface is covered by aeolian sand, with excellent precipitation infiltration capacity. Salinity of surface water and Quaternary water&amp;lt;500 mg/L, the main cation is Ca2+, and the main anion is HCO3-, which belongs to HCO3-Ca·Mg type water. The Cretaceous Zhidan Formation is in unconformable contact with the Quaternary and constitutes a unified water-bearing complex on the whole, which makes Zhidan Formation have a better supply water source, and its inorganic water quality characteristics are close to the Quaternary water. The deep aquifer is affected by the Anding Formation relative impermeable layer and has weak recharge runoff condition. The salinity of Jurassic water is generally &amp;gt;3500 mg/L due to long-term water-rock action. The main cation is Na+, and the main anion is SO42-, which belongs to SO4-Na type water. According to the analysis of hydrochemical characteristics, there is no direct hydraulic connection between Luohe Formation and Zhiluo Formation. The characteristics of environmental isotopes show that the rainwater, surface water, and Quaternary water in the study area belong to the modern groundwater, while Zhidan Formation water is between the modern groundwater and the ancient water. The values of δD and δ18O in the deep Zhiluo Formation and Yan’an Formation are low, and the groundwater falls below the rainwater line of Ordos Basin with a deep circulation depth. Before mining, the groundwater is in a stagnant state with good closed conditions. Qualitative and quantitative signatures of various organic components in water are on the basis of organic geochemistry and hydrogeology, in order to facilitate the study of the quantity, composition, and distribution patterns of organic substances in groundwater and their role in geological, geochemical, and other processes. By testing the organic matter of dissolved organic matter (DOM) in each aquifer, the organic water chemistry characteristics of each aquifer in the Taokutu well field can be established. The content of dissolved organic matter (TOC and UV254) in groundwater decreases gradually with the increase of aquifer depth. Fluorescence peaks in Area I and Area III mainly appeared in surface water and Quaternary water, and DOM sources were more abundant in surface water. The fluorescence peak in Area I also appears in the water of Zhidan Formation, Zhiluo Formation, and Yan’an Formation, and the fluorescence peak between Area I and Area II is a symbol. The fluorescence peak intensity of Cretaceous → Zhiluo Formation in Area V area has an increasing trend, indicating that there are humus-like DOM from other sources in the deep Zhiluo Formation aquifer. In general, the comprehensive analysis of hydrochemical characteristics by various means can well distinguish the differences of hydrogeochemical characteristics among aquifers, which provides a scientific basis for the rapid and accurate discrimination of water situation and disaster in coal mines and the safe production.

Perfluoroalkyl and Polyfluoroalkyl Substances in Groundwater Used as a Source of Drinking Water in the Eastern United States.

In 2019, 254 samples were collected from five aquifer systems to evaluate perfluoroalkyl and polyfluoroalkyl substance (PFAS) occurrence in groundwater used as a source of drinking water in the eastern United States. The samples were analyzed for 24 PFAS, major ions, nutrients, trace elements, dissolved organic carbon (DOC), volatile organic compounds (VOCs), pharmaceuticals, and tritium. Fourteen of the 24 PFAS were detected in groundwater, with 60 and 20% of public-supply and domestic wells, respectively, containing at least one PFAS detection. Concentrations of tritium, chloride, sulfate, DOC, and manganese + iron; percent urban land use within 500 m of the wells; and VOC and pharmaceutical detection frequencies were significantly higher in samples containing PFAS detections than in samples with no detections. Boosted regression tree models that consider 57 chemical and land-use variables show that tritium concentration, distance to the nearest fire-training area, percentage of urban land use, and DOC and VOC concentrations are the top five predictors of PFAS detections, consistent with the hydrologic position, geochemistry, and land use being important controls on PFAS occurrence in groundwater. Model results indicate that it may be possible to predict PFAS detections in groundwater using existing data sources.

Screening and prioritizing substances in groundwater in the Beijing–Tianjin–Hebei region of the North China Plain based on exposure and hazard assessments

Screening and prioritizing hazardous substances in groundwater is crucial to monitor and control groundwater quality. Total of 283 substances were determined in 213 groundwater samples from the Beijing–Tianjin–Hebei region during 2019–2020. 184 substances were screened as candidates. 22 prioritizing indicators were evaluated and scored for the candidates to reflect their occurrence, mobility, persistence, bioaccumulation, acute and chronic ecotoxicities with different trophic levels, and long-term human health effects. Multi-attribute decision-making technologies were applied to prioritize these candidates, including analytic hierarchy process (AHP), TOPSIS and VIKOR. Greater weightings in AHP were assigned to attributes of occurrence and acute toxicity by experts’ judgment. Hierarchical cluster analysis and principal component analysis were used to transform initial matrix with the 22 indicators into an orthogonalized matrix with 6 principal components, which represented general toxicity to aquatic organism and mammal, bioaccumulation, carcinogenicity & mutagenicity, persistence, and teratogenicity & endocrine, respectively. VIKOR and TOPSIS results were similar, but different from the AHP ranking. Two filter criteria harmonized their difference. Twenty-three substances were proposed as the priority substance with high hazard and potential exposure, and nitrate-nitrogen and ammonia-nitrogen were selected as additional priority substance frequently and extensively exceeding official groundwater quality standard on the regional scale.

Sonolytic destruction of Per- and polyfluoroalkyl substances in groundwater, aqueous Film-Forming Foams, and investigation derived waste

Per- and polyfluoroalkyl substances (PFASs) are anthropogenic amphipathic heat-resistant materials found in some household products and Aqueous Film-Forming Foams (AFFFs) used to extinguish hydrocarbon fires. There is a critical need for developing destructive technologies for the treatment of PFAS-impacted waters because several PFASs are classified as probable carcinogens and endocrine disruptors. We tested the destruction of 7 individual PFASs, a mix of 24 native PFASs (24Mix), and samples of AFFF and concentrated Investigation Derived Waste (IDW) by high-frequency ultrasound (700 kHz – 1040 W) in deionized water, groundwater containing low total dissolved solids (TDS) (388 mg L−1), and high-TDS groundwater (10.2 g L−1). This study demonstrated the degradation of novel PFASs, hexafluoropropylene oxide dimer acid (HFPO-DA) and 6:2 fluorotelomer sulfonamidoalkyl betaine (6:2 FTAB), with near-stoichiometric fluoride release. The salts and surfactants affect the air-water partitioning coefficients of PFASs and their availability at the ultrasonic cavity, thereby affecting the degradation rates. The degradation rates of sulfonates and short-chain PFASs were 30% to 60% higher in low TDS groundwater than those in deionized water, while the rates were lower in high TDS groundwater. The degradation rates of sulfonates in AFFF were 40% to 60% higher as compared to the 24Mix. The treatment of concentrated, high-TDS IDW resulted in significant defluorination of 41 PFASs, consuming 3 kWh g−1 – 76 kWh g−1 whereas dilute AFFF degradation utilized 5900 kWh g−1. The results inform important parameters for designing and operating ultrasonic reactors for the degradation of PFASs and verify that sonolytic treatment of concentrated PFAS mixtures and AFFF IDWs can effectively degrade and defluorinate PFASs without the formation of disinfection by-products.

Field Demonstration of a Pilot-Scale Plasma Reactor for the Rapid Removal of Poly- and Perfluoroalkyl Substances in Groundwater

A pilot-scale plasma-based water treatment system containing two enhanced contact plasma reactors was deployed to a fire training area at Wright-Patterson Air Force Base to treat poly- and perfluor...

МҰНАЙ ҚҰРАМДЫ ӨНДІРІСТІК САРҚЫНДЫЛАРДЫҢ КАСПИЙ ТЕҢІЗІНІҢ ЖАҒАЛАУ СУЛАРЫНА ӘСЕРІ

The article considers the influence of oil-containing wastewater generated from industrial enterprises located on the coast of the Caspian Sea, through underground drains on the groundwater and sea water of the Caspian Sea coast within the Mangistau region, the content of controlled pollutants in the studied samples is given. To determine the dynamics of changes in the level of harmful substances in underground and surface waters, 3 production facilities engaged in oil production and processing, located at different distances from the sea, were selected.Two of them are located on the seashore, one object is located 8 km from the Caspian Sea. In 3 studied objects, wastewater that has been treated is discharged into the reservoir. The work consisted in studying the production area, monitoring the level and temperature of underground and surface waters and conducting laboratory analysis of the content of polluting components in the water using marine stations and hydrogeological observation wells located in the study area. For marine waters in the vicinity of the Karazhanbas field was observed deviations from the concentrations of oil content and iron, the oscillation of the norm of certain substances in groundwater due to the fact that the underground water of the region in the area belong to the province of underground water with high concentration of heavy metals and organic substances and are of chloride-sulfate chemical composition.