Groundwater Pollution Prevention Research Articles

Aquifer vulnerability assessment for fecal coliform bacteria using multi-threshold logistic regression.

Assessing aquifer vulnerability is crucial for preventing groundwater pollution. In this study, aquifer vulnerability to fecal coliform (FC) pollution was assessed using auxiliary environmental data in the Pingtung Plain, Taiwan. Moreover, key environmental factors inducing different fecal pollution levels were determined. First, 23 explanatory variables on land uses, population density, livestock and poultry densities, sanitary condition, antecedent precipitation, groundwater quality, aquifer characteristics, and subsurface hydrology were obtained using geographic information systems in 2014. As dependent variables, groundwater FCs were also simultaneously obtained. Then, multi-threshold logistic regression (LR) was adopted to model aquifer vulnerability assessment after cross validation. The thresholds of aquifer vulnerability causing risks of incidental ingestion were analyzed by risk assessment. Risks to human health were acceptable for a low-level threshold and exceeded the acceptable level for medium- and high-level thresholds when residents incidentally ingested FC-polluted groundwater. Finally, key environmental factors inducing low, medium, and high levels of groundwater FC pollution were characterized. The key environmental factors for the LR with low- and medium-level thresholds were sand and gravel soil textures of unsaturated aquifers and antecedent 3-day cumulative precipitation, and those for the LR with high-level thresholds were chicken farming, urban land use, and ratio of tap water use. Thus, the multi-threshold LR indicated that environmental factors must be ranked for assessing aquifer vulnerability.

Evaluating groundwater pollution with emphasizing heavy metal hotspots in an urbanized alluvium watershed of Yamuna River, northern India

For the management and prevention of groundwater pollution in the basin, a comprehensive evaluation of groundwater contamination hazards is required. The anthropogenic activities play a vital role in groundwater pollution of the alluvium watershed of Yamuna River in Mathura district through the infiltration process. In this study, several groundwater pollution indices such as pollution index of groundwater (PIG), heavy metal pollution index (HPI), ecological risk index (ERI) and multivariate approach i.e., Principal component analysis (PCA) have been used to detect the contaminated hotspots of the study area. During the study, 110 groundwater samples were collected from shallow hand-pumps to assess the groundwater quality based on selective major ions mainly Chloride, Sulphate, Nitrate, and Fluoride and heavy metals such as Zinc, Lead, Nickel, Cadmium, Iron, Chromium, Manganese and Copper respectively. The results show that the average heavy metal concentrations follow the trend of Ni (2.92 mg/L) > Pb (2.06 mg/L) > Fe (1.73 mg/L) > Zn (0.76 mg/L) > Cr (0.66 mg/L) > Cd (0.45 mg/L) > Mn (0.40 mg/L) > Cu (0.02 mg/L) respectively. Likewise, ERI results indicate a high potential ecological risk in the study area. Based on this, we classify the groundwater samples into good (9.10 %), poor (13.6 %), and very poor quality (77.3 %). The hotspots are found in the Northwestern region of the study area. The findings indicate that the escalation of municipal waste, industrial waste, agriculture applications and practices in the alluvium watershed of Yamuna River, directly and indirectly, affects the groundwater aquifers. This elaborate study helps in designing an appropriate mitigation strategy for pollution containment as well as proper water resources management.

Source apportionment of nitrates in different aquifers in an arid region, northwestern China

The nitrate pollution of groundwater in arid areas subject to human activity, and especially agricultural activity, is of immense environmental concern. Groundwater is the main water source in arid areas, once an aquifer is polluted, the impact upon the security of the water supply becomes all the more serious. The process of nitrate transformation is also different from that of humid areas, therefore, it is very important to identify and quantify the nitrate sources in aquifers. Using the hydrochemical, stable isotope tracers of 194 groundwater samples, and combining these with the MixSIAR model, the spatial distribution of groundwater nitrates in the Shiyang River Basin (SRB), China, was mapped. The relative contributions made by nitrate sources to different aquifers, and their key transformation processes, were identified. It was found that, shallow groundwater is seriously polluted, with NO3− concentrations ranging from 1.1 to 438.7 mg L−1. In the SRB, NO3− concentrations of 23% and 73% in shallow groundwater samples exceed the NO3− concentration limits found in natural sources (13.3 mg L−1), and the World Health Organization (WHO) nitrate limits for drinking water (50 mg L−1). Furthermore, the nitrates found in confined aquifers indicate that these are also affected by anthropogenic sources, with concentrations ranging from 1.6 to 44.7 mg L−1. Soil organic nitrogen (51.9%) and NH4+ fertilizer (20.8%), wastewater and manure (20.5%) are the main sources of groundwater nitrates; NO3− fertilizer (4.4%) and precipitation (2.3%) have a relatively insignificant effect on groundwater nitrates. The process of nitrification is the main factor affecting changes in nitrate concentrations in aquifers. Other than the denitrification observed in the shallow aquifers of the Minqin Basin (MQB), there was no significant denitrification in the other sub-basins of the SRB. Anthropogenic sources, especially agricultural sources, are now major contributors to the increases in groundwater nitrate concentrations observed in the SRB. This study provides data that can be used to help prevent groundwater pollution and enhance water resources management in arid areas.

Use of cover crops in vineyards to prevent groundwater pollution by copper and organic fungicides. Soil column studies.

Several fungicides, such as copper and organic products (synthetic or natural), are currently being used in vineyards to control downy mildew (Plasmopara viticola) resulting in soil, surface water, and groundwater pollution. This study aims to assess the effectiveness of using cover crops as an agricultural practice in vineyards to protect soil and groundwater pollution. For that purpose, we performed different soil column studies to quantify soil leaching of selected fungicides (copper, dimethomorph, oxathiapiprolin, zoxamide, acibenzolar-s-methyl, and laminarin) following a rainfall event after a conventional fungicide vineyard application. Two types of vineyard soils (loam and sandy-loam soil textures) and three ground covers (bare ground, monoculture cover, and polyculture cover) were assessed. These studies were completed with hydroponic assays to check the effectiveness of cover roots in the fungicide degradation. Mass balance results show that whereas 3 fungicides (Cu, zoxamide, and dimethomorph) were leached through sandy soil columns, only copper was leached from loam soil columns. The effect of cover crops was only significant for Cu and zoxamide when fungicides were applied 24h before the rain event, reducing the fungicide leaching by 30%. Hydroponic studies showed that cover roots enhanced the kinetic rates of almost all tested fungicides by 5-467%, suggesting that they are relevant to improving the degradation of fungicides in the soil column. These results are relevant to drawing up recommendations on the use of cover crops to protect soil and groundwater pollution by fungicides.

Groundwater Pollution Source Identification by Combination of PMF Model and Stable Isotope Technology

The pollution source identification methods based on traditional water quality monitoring and pollutant discharge loading typically require a high frequency of monitoring and generate a level of uncertainty in the identification results, owing to their limitations on the accurate and quantitative assessment of pollution source identification, migration, and transformation. This study combined multivariate statistical analysis and stable isotope technology to identify groundwater pollution sources in a typical multiple land-use area of the Chengdu Plain. A positive matrix factorization (PMF) model was adopted to reduce the interference of mass environmental factors on source identification and to determine the main factors influencing groundwater quality. Subsequently, a Bayesian stable isotope mixing model was developed to quantify the apportionment of each pollution source to groundwater nitrate (NO3-) with the consideration of hydro-chemical and land-use information. The results showed that the concentrations of NO3-, NO2-, NH4+, Mn, Fe, SO42-, and Cl- in groundwater of the study area exceeded the standard to different extents, presenting spatial variation. The main form of inorganic nitrogen in groundwater was NO3-. In general, concentrations of groundwater NO3- were the highest in vegetable fields (9.29 mg·L-1 on average), followed by livestock and poultry breeding farms (7.66 mg·L-1) and arable land (7.09 mg·L-1), whereas concentrations of groundwater NO3- in industrial areas were the lowest (2.20 mg·L-1). Groundwater quality in the study area was affected by geological processes, agricultural activities, hydrogeochemical evolution, and domestic and industrial discharges. Agricultural activities were the main contributor to the increase in groundwater NO3- in the study area. Chemical fertilizer (32%) and soil nitrogen (25%) contributed greatly to groundwater NO3- in agricultural areas, whereas sewage (28%) and atmospheric precipitation (27%) contributed most groundwater NO3- in industrial areas. Thus, the combination of multivariate statistical analysis and stable isotope technology could identify groundwater pollution sources and their apportionment effectively, providing scientific support for the prevention and control of groundwater pollution.

Performance study of cement-based grouts based on testing and thermal conductivity modeling for ground-source heat pumps

The annulus zone between the vertical ground heat exchanger and borehole wall needs to be filled with grout to enhance heat exchange and prevent groundwater pollution. However, studies on porosity, the dual influence of water-to-cement and sand-to-cement ratios on material properties and theoretical studies need to be deepened. Hence, the flowability, thermal conductivity, and porosity of cement-based grouts with various proportions were tested. It was found that the increase in the sand-to-cement ratio and decrease in the water-to-cement ratio helps in the augmentation of thermal conductivity and decrease of porosity, but lowers the flowability. When the water-to-cement ratio is 0.55, a sand-to-cement ratio higher than 2.0 will lead to excessive fissures and thus weaken the thermal conductivity. The maximum thermal conductivity reaches 2.10 W·m−1·K−1 in the saturated state with a porosity of 0.2442. A high porosity indicates a larger permeability and poor thermal performance; therefore, the suggested porosity is below 0.43. Moreover, the thermal conductivity-change mechanism was studied by the series–parallel thermal conductivity model, which can predict the thermal conductivity with an error of less than 10 %. The model shows that the heat conduction of the components in the grout is mainly in series. Additionally, improving the sand-to-cement ratio, maintaining high saturation, reducing the porosity, and adding high-performance aggregates are all ways to improve the thermal conductivity of the material. And the grouts-taking value area is also marked out.

Coupling electrokinetic with a cork-based permeable reactive barrier to prevent groundwater pollution: A case study on hexavalent chromium-contaminated soil

This work proposes an eco-efficient treatment technology for the remediation of a kaolinite-based clay soil artificially contaminated with hexavalent chromium (50 mg Cr(VI) kg–1 soil), combining electrokinetics (EK) with permeable reactive barriers (PRB) composed of cork granules, the major by-product of cork stoppers production. This 100% natural and sustainable material can act as (i) an electron donor in the Cr(VI) reduction into trivalent chromium [Cr(III)], the less toxic state, and as (ii) a binder for the reduced Cr(III) on its pre-oxidized surface. The EK and Cr(VI) reduction efficiencies were assessed over 15 days as a function of the: (i) supporting electrolyte solution (demineralized water – DW, tap water, citric acid – CA, and sodium chloride – NaCl); and (ii) cork-PRB inclusion and position (near the anodic compartment, using direct current, or in the soil middle section, applying reversal polarity). Results showed that DW was the best supporting electrolyte solution, removing about 33% of total chromium (CrT) from the soil towards the anode, mainly under the Cr(VI) form, even though CA and NaCl presented higher electrical conductivity. Besides, nearly 67% Cr(VI) was reduced into less mobile Cr(III) only by soil-borne electron donor constituents, especially iron (> 6 g kg–1), which impaired the overall Cr migration due to the Cr(III) precipitation/adsorption over/onto the soil. Such reaction was boosted by CA and NaCl electrolytes, which increased H+ ions availability, reaching reduction efficiencies higher than 98%. When the cork-PRB was incorporated into the DW-driven EK process near the anode, the best position owing to the low pH, the Cr(VI) reduction and CrT removal efficiencies improved to about 97% and 42%, respectively. Furthermore, virtually no Cr(VI) migrated to the anolyte/catholyte, and less than 2% Cr(III) was found in the anodic chamber, being c.a. 40% of CrT retained in the cork-PRB as Cr(III) and c.a. 3%/55% of Cr(VI)/Cr(III) into the soil. Notwithstanding, the EK-PRB process can render polluted soil somewhat less dangerous and prevent the spreading of contamination to natural aquifers.

EVOLUTION TREND AND HOT ISSUES OF GROUNDWATER ENVIRONMENT RESEARCH IN RECENT 40 YEARS BASED ON EMOTIONAL BEHAVIOR CHANGES: A SUMMARY OF SCIENTIFIC ECONOMETRIC ANALYSIS FROM 1981 TO 2021

BackgroundGroundwater pollution has become an important factor restricting regional economic development and environmental protection. The prevention and control of groundwater pollution has always been the focus of water resources management scholars. The purpose of this study is to systematically evaluate the knowledge system of groundwater pollution prevention and control from 1981 to 2021, and to explore the research trend and hot spots of groundwater pollution prevention and control knowledge system. And the emotional and behavioral changes of water conservancy workers.Topics and MethodsIn the field of groundwater environment from 1981 to 2021, taking “science network” (WOS) as the literature source database, the literature system and bibliometric characteristics were studied by means of bibliometrics, knowledge atlas and collaborative research. Occurrence analysis. This paper attempts to evaluate and sort out the similarities and differences between frontier hotspots and evolution trends in the field of groundwater environment. At the same time, the emotional behavior of water conservancy workers in various places was investigated. In order to investigate the regulation of psychological expectation on the emotional arousal effect of negative stimulation and its corresponding neural mechanism when excluding any cognitive strategy involvement in the emotional expectation stage. It is intended to mainly manipulate the predictability (predictable / unpredictable) and potency (negative / neutral) of the target stimulus. The experimental task is the expected stage from the emergence of the negative cue to the presentation of the negative target. The subjects are required to only pay attention to the fixation point in the center of the screen after watching the negative cue and do not take any coping strategies for the subsequent negative stimulus. In order to eliminate the fatigue effect, the experiment is divided into four sections. At the end of each section, the subjects took a proper rest, and then tested the success degree of the subjects following the experimental guidance requirement of “only pay attention to the fixation point from the presentation of the cord stimulus to the appearance of the target stimulus”, and scored with a 5-point scale (1 = very unsuccessful, 5 = very successful) to evaluate the success degree of non cognitive manipulation. 36 healthy subjects, 18 men and 18 women, were recruited to rule out possible gender differences in the process of emotional expectation (Galli et al., 2011). All subjects filled in the state trait anxiety questionnaire and Beck depression questionnaire before participating in the experiment to eliminate the possibility of anxiety disorder or depressive tendency. The experiment intends to simultaneously record the activity level of peripheral physiological indexes such as event-related brain potential (ERP), skin electricity, heart rate and skin temperature and frowning electromyography (electromyography index directly related to the negative expression of subjects under negative stimulation), so as to comprehensively reveal how the EEG, peripheral physiological activity level and electromyography activity level related to negative emotion change with expected factors.ResultsGroundwater pollution prevention and control is a general theory in the field of environmental risk of groundwater at home and abroad. There are many core trends in groundwater pollution prevention and control. This paper gives the evolution track, development stage and dynamic change of the research topic.ConclusionIn recent 40 years, the research on the change law of hot spot migration can be divided into three stages. 2009 is a watershed, and the problem has undergone earth shaking changes. Through the visual analysis of knowledge base system, 12 research hotspots are summarized. Explore the change law of topics in the form of dynamic knowledge map, observe the migration of research hotspots, and provide evidence and discussion for research trends and recent hotspots.AcknowledgementsSupported by a project grant from Key R&D Program of Shaanxi Province (Grant No. D5140200023) and Xi 'an Geological Survey, China Geological Survey (Grant No.211527180141).

Assessment of groundwater vulnerability in an urban area: a comparative study based on DRASTIC, EBF, and LR models.

The groundwater vulnerability assessment is known as a useful tool for predicting and prevention of groundwater pollution. This study targets the DRASTIC, evidential belief function (EBF), and logistic regression (LR) models to assess vulnerability in Kabul aquifers, Afghanistan Country. The growth of urban sprawl, groundwater overexploitation, and lack of suitable municipal sewage systems as anthropogenic sources have been the main potential to increase groundwater contaminants such as nitrate in the study area. The vulnerability map has been developed based on various effective factors including altitude, slope (percentage rise), aspect, curvature, land-use type, drainage density, distance from river, annual mean precipitation, net recharge, geology/lithology units, the impact of the vadose zone, aquifer media, depth to water (unsaturated zone), saturated zone, drawdown, and hydraulic conductivity. To identify groundwater pollution, the spatial variation of nitrate concentration data in 2018 was considered indication of groundwater pollution. Based on descriptive statistics, the value of 2.65mg/l (the median of the pixel values of nitrate map) was selected as a threshold to differentiate the occurrence and non-occurrence of pollution. The groundwater quality data were selected and randomly divided into two datasets for training and validation, including 70% and 30%, respectively. The success-rate and prediction-rate curves were computed based on the receiver operating characteristic (ROC) curve and the area under the curve (AUC) to estimate the efficiency of models. The ROC-AUC of success rates for EBF, LR, and DRASTIC models were estimated to be 67%, 66%, and 52%, respectively. Moreover, the ROC-AUC of the prediction rates of the EBF, LR, and DRASTIC models were obtained 61%, 63%, and 55%, respectively. Based on correlation between mean nitrate concentration and the mean vulnerability indexes in each model, the EBF model is the most compatible with the current developed vulnerability zones as the role of mankind in changing the environment in real conditions in comparison to LR and DRASTIC models.

Groundwater Pollution Model and Diffusion Law in Ordovician Limestone Aquifer Owe to Abandoned Red Mud Tailing Pit

Red mud is a strong alkaline solid waste pollutant produced in the process of aluminum smelting, which causes great pollution to the regional groundwater environment due to its high content of fluorine and aluminum and high concentration of strong alkali. In this study, fluoride ion was selected as the model contaminant, and a numerical model of the groundwater flow field and solute transport was developed using GMS software to simulate and analyze the migration patterns of fluoride contaminants caused by the red mud pit for the fractured karst geohydrological conditions. The results demonstrated that the groundwater model and flow pattern were mainly controlled by atmospheric precipitation recharge, given flow boundary conditions and leakage of rivers and drains. When the concentration of fluorine pollutants in the red mud yard was 60.0 mg/L, the maximum migration distance of F− in the groundwater of the ordovician limestone aquifer was 473, 1160, 1595 and 1750 m after 1, 5, 10 and 15 years of bottom leakage, and the additional transport distances were 687, 435 and 155 m every 5 years, respectively. The range of F− pollution plume was 0.37 km2, 1.15 km2, 1.95 km2 and 2.14 km2, respectively and the range of newly added pollution plume was 0.78 km2, 0.80 km2 and 0.19 km2, respectively, every five years. Both indicated that with the extension of time, the migration and diffusion rate of pollutants slow down, and the diffusion volume increased first and then decreased. The F− pollution plume spread from the red mud pit to the northeast, which was consistent with the flow of groundwater. The high-concentration pollution plume was mainly distributed in the Ordovician limestone fractured aquifer in the northeast. This study revealed the migration law of red mud pollutants, and provided a scientific decision-making basis for the prevention and control of red mud groundwater pollution in the future.

Technical solutions and benefits of introducing rain gardens – Gdańsk case study

Nowadays, Nature-Based Solutions (NBSs) are developing as innovative multifunctional tools to maximize urban ecosystem services such as storm water preservation, reduction of runoff and flood protection, groundwater pollution prevention, biodiversity enhancement, and microclimate control. Gdańsk is one of the first Polish cities to widely introduce rain gardens (one example of an NBS) in different areas such as parks, city center, main crossroads, and car parks. They involve different technical innovations individually tailored to local architecture, including historic buildings and spaces. Gdańskie Wody, which is responsible for storm water management in the city, adopted a pioneering strategy and started the construction of the first rain garden in 2018. Currently, there are a dozen rain gardens in the city, and this organisation's policy stipulates the construction of NBSs in new housing estates without building rainwater drainage.Various types of rain gardens can be created depending on location characteristics such as geo-hydrology, as well as local conditions and needs. Furthermore, each of them might be equipped with specific technical solutions to improve the rain garden's function – for example, an oil separator or setter can be included to absorb the initial, most polluted runoff. During winter, the large amount of sodium chloride usually used to grit the roads may pose the greatest threat to biodiversity and plants. These installations have been included in a large rain garden in Gdańsk, located in the central reservation of the main streets in the city center.This work presents various technical considerations and their impact on ecosystem functions, and the urban circularity challenges provided by rain gardens operating in different technologies and surroundings. The precipitation quantity and the following infiltration rate were estimated by installing pressure transducers. Furthermore, mitigation of the urban heat island was analysed based on remote sensing images.

Analysis and Suitability of Treated Wastewater of Various Units at Amberpet STP, Hyderabad

The primary goal of wastewater treatment is to enable municipal and industrial effluents to be disposed of without endangering public health or causing unacceptable ecological damage. With rapid urbanization and industrialization, both the quantity of sewage generation and complexity in its treatment for recycle is increasing. Further, the disposal of untreated sewage is posing lot of threat to groundwater quality. Hence, recycling of wastewater is necessary to prevent groundwater pollution. It also helps in augmenting water conservation. Sewage can be treated to the acceptable quality for its use in many non-potable, industrial and agricultural uses. Treated wastewater recycling helps in addressing the rapidly growing water consumption of many areas of the economy thereby benefiting in environmental rehabilitation. From the perception of public resource, the present study analyzes the suitability of treated wastewater from various units at Amberpet STP in Hyderabad for several designated water uses.

Sustainability of groundwater resources of weathered and fractured schists in the rural areas of Galicia (Spain)

Water supply deficits in droughts, groundwater pollution and climate change are the main challenges for the sustainability of groundwater resources from hard-rock aquifers in rural areas of Galicia (Spain). Here, we address the sustainability of groundwater resources of weathered and fractured schists in the rural areas of the Abegondo municipality. The conceptualization of the hydrogeology of the study area includes: (1) The weathered schist (regolith), (2) The decompressed highly fractured schist layer; and (3) An underlying slightly fractured schist. Groundwater flows mostly through the regolith and the highly fractured rock. Rainfall infiltration is the source of aquifer recharge. Groundwater discharges in seepage areas, springs and along creeks and valleys. The water table is generally shallow and shows seasonal oscillations of up to 4 m. The equivalent transmissivity of the regolith and the highly fractured schist ranges from 15 to 35 m2/days. The electrical resistivity tomography identifies a shallow water table and attests that the contact of the highly fractured schist and the slightly fractured schist is highly heterogeneous. Groundwater resources were quantified with a hydrological water balance model. The mean annual recharge is about 185 mm. Groundwater recharge at the end of the twenty-first century could decrease from 6 to 10% due to climate change. The decline in groundwater table could aggravate the shortages during droughts. Groundwater quality data show bacteriological and nitrate contamination due to the poor management of the manure in the fields and occasional discharges of slurry from pig and mink farms. Groundwater management and protection actions are proposed to prevent groundwater pollution and achieve a sustainable groundwater supply in the study area.

Groundwater Pollution Prevention and Control in China: Current Status and Countermeasures

Groundwater Pollution Prevention and Control in China: Current Status and Countermeasures

Contaminant migration and the retention behavior of a laterite–bentonite mixture engineered barrier in a landfill

Groundwater pollution has become increasingly severe in recent years, particularly owing to leachate leakage in landfills. In this study, the migration of Cu2+ in a landfill and the retention behavior of a compacted laterite-bentonite engineered barrier system toward the contaminant were analyzed by a numerical simulation based on laboratory and field test results. The results show that the hydraulic conductivity of the laterite–bentonite mixture decreased with an increase in the bentonite ratio: The hydraulic conductivities of the laterite–bentonite mixture were 4.718 × 10−7, 2.103 × 10−7, 7.899 × 10−8, 3.918 × 10−8, and 1.614 × 10−8 cm/s when the bentonite ratios were 0, 2%, 5%, 10%, and 20%, respectively. The hydraulic conductivity of laterite and of the mixture with a bentonite ratio of 2% decreased gradually under infiltration of deionized water and CuSO4 solutions with concentrations of 0.01 and 0.1 mol/L. This could be attributed to the increased degree of flocculation of laterite with the increase in the solution concentration. The results of the numerical simulation indicate that the migration range of Cu2+ after 3650 days was approximately 1500 m. The retention efficiency of a 0.5 m engineered barrier for Cu2+ was 67%. However, the retention efficiency exceeded 83% when the engineered barrier thickness was increased to 1.0 m. The results of the laboratory tests and numerical simulation demonstrate that a compacted laterite–bentonite engineered barrier system has a good retention effect on Cu2+. These observations may provide effective concepts for the prevention and control of groundwater pollution in landfills.

A GIS-based analysis of intrinsic vulnerability, pollution load, and function value for the assessment of groundwater pollution and health risk

Groundwater pollution risk assessment is an effective tool for the control and prevention of groundwater pollution. However, the risk is generally difficult to interpret because it is affected by both natural and anthropic factors such as topography, aquifer characteristics, land-use changes, and mining process. In this study, a GIS-based analysis of aquifer vulnerability (V), groundwater pollution load (L), and groundwater function value (F) were combined to comprehensively evaluate the groundwater pollution risk in a typical mixed land use area of Chengdu Plain, in China. Groundwater pollution risk assessment was then validated by a groundwater quality evaluation using the comprehensive water quality index method. A health risk assessment was conducted to evaluate the susceptible population exposed to the groundwater pollution. The results showed that the estimated ‘high’ and ‘very high’ pollution risk areas together accounted for 24.85% of the study area, mainly located in the southeast and southwest of the plain area with highly permeable aquifer, abundant amounts of groundwater storage, a shallow water table, and near pollution sources. In addition, our results revealed that 14% of groundwater in the study area posed an unacceptable non-carcinogenic health risk to children. The risk assessment of groundwater pollution and human health in the study area can provide effective support for strengthening groundwater management and pollution control.

Retraction Note: Characteristics of urban groundwater pollution based on abnormal data processing and optimization of sports health market

With the rapid development of China’s economy in recent years, the prevention and control of groundwater pollution has become increasingly acute. With the increasingly serious environmental problems of groundwater, it is of great significance to study groundwater. In order to correctly understand the groundwater environmental quality in a certain area and make the groundwater pollution monitoring more targeted, it is urgent to optimize the existing monitoring indicators. By analyzing the direct and indirect effects of features on anomaly detection, this paper designs redundant feature deletion mechanism and feature importance evaluation mechanism, and proposes a mixer mode feature selection algorithm to select groundwater pollution features quickly and accurately. Then, the method of anomaly detection is improved by using the feature selection algorithm, and an anomaly detection technology based on groundwater feature selection is proposed to improve the detection accuracy of all kinds of abnormal data. With the improvement of the living standards of Chinese residents, the demand for sports fitness services is also growing, and the sports fitness consulting service industry supported by the state is also expanding to other fields, which also provides a market for sports fitness consulting services. This paper mainly analyzes and studies China’s sports fitness consulting market by using the methods of literature data, questionnaire survey, expert interview, and case study. Using the relevant knowledge of marketing, based on STP theory, this paper puts forward corresponding strategies from the aspects of product marketing, price marketing, marketing channels, and marketing promotion. Based on abnormal data processing, this paper studies the characteristics of urban groundwater pollution and sports health market.

Retraction Note to: Groundwater pollution prevention based on improved particle swarm algorithm and sports training optimization

Retraction Note to: Groundwater pollution prevention based on improved particle swarm algorithm and sports training optimization

Groundwater Mapping of Total Coliform Contamination in Sleman, Yogyakarta, Indonesia

Groundwater is a pivotal resource to supply clean and drinking water besides surface water. In Indonesia, there are various issues regarding groundwater quality and quantity. By increasing population growth has an impact on groundwater quality, such as generated pathogen contamination. To prevent groundwater pollution was used sanitation facilities were called communal WWTPs. Unfortunately, most WWTPs were not performing optimal, and some had already stopped operating. This study aimed to display groundwater quality using the Inverse Distance Weighting (IDW) for 2018 to 2019 in the Sleman Region of Yogyakarta Province. The spatial analysis was completed by observation and interview methods. The total coliform number was measured from 29 monitoring wells. The results explained that compared to 2018, groundwater quality in 2019 showed a decrease in contamination by pathogenic bacteria. Groundwater flows also shown the spread of contamination from north to the south area. The distance between monitoring well and septic tank or WWTPs outlet, depth, and the physical condition were substantial factors for spreading the contamination.

Groundwater contamination risk assessment using a modified DRATICL model and pollution loading: A case study in the Guanzhong Basin of China

Groundwater contamination risk assessment is not only the basis for groundwater management, but also an effective tool for groundwater pollution control and prevention. However, only groundwater vulnerability assessment is not enough to prove the risk of groundwater contamination. Therefore, this study describes an evaluation method combining aquifer intrinsic vulnerability and pollution source loading to evaluate groundwater contamination risk in Guanzhong Basin on a macro scale. A modified DRATICL model was introduced to evaluate the intrinsic vulnerability, and the analytic hierarchy process (AHP) and the entropy weight method were combined to determine the weight of each evaluation factor. Pollution loading was evaluated by quantifying the characteristics of potential pollution sources, mainly including pollutant toxicity, pollutant release possibility and potential pollutant release amount. Finally, total iron, Cl−, SO42−, F−, COD (Chemical Oxygen Demand), NO3−, NO2− and TDS (Total Dissolved Solids) are used to calculate the water quality index and verify the model results. The results showed that industries were the most harmful potential pollution sources in the study area, followed by landfills. Very high vulnerability areas were mainly situated around Huazhou District, Huayin and Dali County, as well as the low terraces around Zhouzhi County and Hu County, which are mainly caused by shallow groundwater depth and high net recharge. The final groundwater contamination risk results showed the high groundwater contamination risks are detected around Xi'an City, Xianyang City, Hancheng City and Dali County. Both high vulnerability and high pollution loading were present at the Jingwei District in the north of Xi'an City, where a priority attention should be given.