Hydrogeochemical characteristics and water quality assessment of shallow groundwater: a case study from Linhuan coal-mining district in northern Anhui Province, China

Abstract

Major ion and trace element concentrations in shallow groundwater of Linhuan coal-mining district, Northern Anhui Province, China, were analyzed to determine its hydrogeochemical characteristics and to assess drinking and irrigation water quality. The relative abundance of cations and anions was Na+ > Mg2+ > Ca2+ > K+, and HCO3− > SO42− > Cl− > NO3−, respectively. The concentrations of Na+, HCO3−, NO3−, and total dissolved solids (TDS), and the electric conductivity (EC) values in some samples were higher than the permissible limits of the Water Health Organization (WHO). Gibbs diagrams showed that rock weathering mainly controlled the major ion chemistry of the groundwater, and the first aquifer of this study area had a weak hydraulic connection with atmospheric precipitation. The calculated sodium percentage (%Na) and sodium adsorption ratio (SAR) revealed that the slight sodium and high salinity hazards needed to be controlled before irrigation. According to the fuzzy comprehensive assessment, the groundwater samples were classified into four categories. The results showed that 92.86% of the groundwater samples were suitable for drinking use. For human health, the NO3− and Mn levels in the groundwater should be reduced before drinking, and treatment of the high salinity hazards is required before irrigation.

Hydrochemical Characteristics and Water Quality Evaluation of Rivers in Different Regions of Cities: A Case Study of Suzhou City in Northern Anhui Province, China

“…The natural rivers and lakes are commonly controlled significantly by evaporation [35]. Taking the shallow groundwater around Suzhou city as the research object, it is concluded that rock weathering is the main source of ions in this area [15]. However, in this study, the hydrochemical formation mechanism of surface water is similar to that of groundwater, indicating the interaction between groundwater and surface water.…”

“…Correlation analysis was conducted on the nutrition indicators (TP and TN) and major hydrochemical parameters of surface water in the study area, and the results are shown in Figure 7. Because the shallow groundwater in the study area is usually about three meters deep, surface water replenishes groundwater during the rainy season and shallow groundwater replenishes the river during the dry season [15].As can be seen from Figure 7a, Ca 2+ had a good correlation with Mg 2+ , F − , Cl − , SO4 2− , and HCO3 − , indicating the diversity of sources of calcium ions. However, in Figure 7b, Ca 2+ are not well correlated with other water quality parameters; this may indicate the monotony of Ca 2+ source in the Tuo River.…”

Environmental and Health Risks Posed by Heavy Metal Contamination of Groundwater in the Sunan Coal Mine, China

“…This area has a high population density and groundwater is used for both various human requirements and irrigation. In the process of coal mining, gangue, domestic wastewater, and agricultural non-point source pollution affect the hydrogeochemical characteristics of shallow groundwater; this can lead to organic or inorganic pollution and threaten groundwater quality and water supply security [41]. The groundwater aquifer systems in the mining area can be categorized as follows: loose pore, coal measure fractured, carbonate fractured, and interstitial aquifer systems.…”

Geochemical Behaviours and Formation Mechanisms for Elevated Fluoride in the Drinking Groundwater in Sulin Coal-Mining District, Northern Anhui Province, China

“…The area contained 19 coal mines with a total production capacity of 30.00 million t/y [33,34]. After 69 years of mining, a large number of collapsed ponds and coal gangue piles have accumulated on the land surface [35]. Aside from the mining area, most of the land in this area is dedicated to agriculture where wheat and corn are the primary crops.…”