Although riverbank filtration (RBF) has been widely applied in China, the managers do not pay enough attention to the inevitable clogging issues during continuous RBF operation. The RBF site, which is located near the Lalin River, northeastern China, was selected as the study area, and the laboratory column experiments were used to simulate the RBF process and further investigate the physical and chemical clogging. The removal of turbidity (59.4–95.1%), COD (21.9–71.7%), NH₄⁺ (10.9–39.4%), Fe (18.5–64.8%), and Mn (19.8–71.7%) demonstrated the water quality improvement by RBF. Whereas, the significant decrease in permeability (39.6–88.2%) also indicated that the clogging issues could not be ignored during RBF. Among them, the physical clogging-dominated area, chemical clogging-dominated area, and the transition zone were located at 0–12.5%, 37.5–100%, and 12.5–37.5% of the infiltration pathway, respectively. Moreover, the concentration of suspended particle materials, mean size of riverbed sediments, and aquifer media are the major impact factors for physical clogging; the precipitation of soluble constituents and redox reaction and other hydrochemical processes were the major impact factors for chemical clogging. The conclusion of this study can contribute to managers alleviating the clogging issues and improving the effectiveness of the sustainable operation in the local RBF system.

Agricultural production may cause groundwater pollution. This study investigated the characteristics of shallow groundwater pollution in a typical black land agricultural production area in Northeastern China and the geochemical behavior of major pollutants. A total of 27 and 23 shallow groundwater samples were collected for measuring on-site parameters and major components in 2000 and 2014, respectively. The improved integrated approach was used to assess groundwater contamination. The results showed that the groundwater was slightly polluted by agricultural activities. The average concentrations of major ions of shallow groundwater were found to be in the following order: Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ for cations and HCO₃⁻ > SO₄²⁻ > Cl⁻ > NO₃⁻ for anions. Percentages of 7.4% and 34.8% of the total groundwater sample in 2000 and 2014, respectively, indicated that the shallow groundwater quality has gradually worsened in the past few decades. The concentration of NO₃⁻ was a major factor that influenced the observed groundwater quality changes. Scientific and effective fertilization of rice cultivation is an effective way to avoid groundwater pollution, and the improved groundwater quality evaluation methods can further improve the standard of groundwater resource management effectively.

While extant research has predominantly focused on elucidating the mechanisms of fluorine (F⁻) enrichment in groundwater within the North China Plain, the occurrence and formation mechanisms of high-F⁻ groundwater in Xiong’an New Area remain unexplored. Consequently, 365 groundwater samples (172 from shallow groundwater, 193 from deep groundwater) were collected from Xiong’an New Area. Hydrochemical analysis, geochemical modeling, and statistical analysis were used to explore the occurrence and formation mechanisms of high-F⁻ groundwater. The results reveal that the highest F⁻ concentrations in shallow and deep groundwater were up to 3.22 mg/L and 1.79 mg/L, respectively. High-F⁻ groundwater was primarily located at the eastern part of the study area. The distribution area of high-F⁻ shallow groundwater was much greater than that of deep groundwater. F-bearing minerals dissolution and ion exchange were the principal formation mechanisms of high-F⁻ groundwater in both shallow and deep aquifers. Moreover, competitive adsorption, evaporation, and the impacts of Ca²⁺ and Mg²⁺ dissolution equilibrium on F-bearing dissolution were crucial to the formation of high-F⁻ groundwater in shallow aquifers. Desorption in an alkaline environment, evaporites dissolution and salt effects were vital to the formation of high-F⁻ groundwater in deep aquifers. These findings can contribute to the support of local groundwater security and management.

Groundwater is the main source of drinking, irrigation, and ecological water in the Baiyangdian Lake Basin (BLB), but growing human activity has raised concerns about its quality. This study assesses major ion geochemistry and multi-receptor environmental risks across the BLB using 1113 groundwater samples (983 shallow, 130 deep). Risks to drinking water supply, agricultural irrigation, and wetland health are evaluated within a single framework, and Positive Matrix Factorization (PMF) is used for quantitative source apportionment. Shallow groundwater shows markedly higher dissolved solids and nitrate than deep groundwater, with 20.7% of shallow samples exceeding the WHO nitrate guideline. Multi-receptor assessment finds that 41.2% of shallow wells pose risk to at least one endpoint and 12.5% to two or more simultaneously. PMF identifies three sources—geogenic weathering, agricultural nitrate, and wastewater discharge—with nitrate as the largest single contributor to water quality impairment. The findings point to an urgent need for targeted agricultural non-point source control and provide a basis for nested, multi-scale groundwater management in the BLB and similar intensively exploited alluvial aquifers.