Journal of contaminant hydrology最新文献

{"title":"Unified analytical framework for multi-dimensional solute transport in fractured porous media","authors":"V.G. Rumynin ,&nbsp;L.N. Sindalovskiy","doi":"10.1016/j.jconhyd.2025.104793","DOIUrl":"10.1016/j.jconhyd.2025.104793","url":null,"abstract":"<div><div>In this paper, we summarize solutions derived previously for solute transport through fractured porous media in a simplified layered setting, extending them to account for the diversity of the fracture–matrix mass transfer models, multi-dimensionality of the hydrodynamic dispersion in the fracture domain, the geometry of contamination sources (conceptualized as point, linear, plane, or parallelepiped) containing sorbed and decaying chemicals with typical inlet boundary conditions. Thus, a new analytical solution for the concentration field was derived. This solution unifies many existing approaches and models and enables the prediction of dual-porosity media behavior under new configurations of initial–boundary conditions and mass-transfer conceptualizations in the fracture–matrix system, considering the solute transport problem in an extended physical setting. The analysis was based on the dual-continuum approach for groundwater flow and solute transport in fractured geological media with a periodic matrix block arrangement, employing a method that decouples the complex solute transport by expressing the general solution of the ADEs in a convolution integral form. We verified the suggested approach and new analytical solutions against the previously published mass transport solutions related to homogeneous and dual-porosity systems.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104793"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical investigation of colloid-facilitated strontium transport in fractured granite under different hydrogeochemical conditions","authors":"Funing Ma ,&nbsp;Fangfei Cai ,&nbsp;Lihong Zhang ,&nbsp;Sida Jia","doi":"10.1016/j.jconhyd.2026.104858","DOIUrl":"10.1016/j.jconhyd.2026.104858","url":null,"abstract":"<div><div>Accurate prediction of radionuclide transport in fractured crystalline rock is vital for the long-term safety of high-level radioactive waste (HLW) geological disposal. However, the specific threshold conditions determining whether bentonite colloids (BC) facilitate or inhibit radionuclide transport in realistic fracture geometries remain quantitatively undefined. This study systematically investigates the transport of strontium (Sr) in fractured granite with and without BC, employing both column experiments and numerical simulations. The effects of varying hydrogeochemical conditions, including flow velocity (1.8–7.2 mL/h), pH (6.5–8.5), and ionic strength (0.001–0.1 M), were quantitatively evaluated. The results revealed that in the absence of colloids, Sr migration was primarily governed by non-equilibrium sorption interactions with the rock matrix. Lower flow velocities enhanced the solute residence time and interaction with the rock surface, promoting retention, while acidic conditions increased Sr mobility by reducing surface complexation. Crucially, the study reveals a complex dual role of BC dictated by hydrogeochemical thresholds. Under high flow velocity and low ionic strength, BC acted as effective carriers, facilitating Sr migration. In contrast, a distinct transition to transport inhibition was observed under low flow velocities or high ionic strength. Under these conditions, the stability of BC was compromised, leading to aggregation and straining within the fracture. This induced a site-shielding effect, where deposited colloids physically blocked sorption sites on the rock matrix, effectively retarding Sr transport. These findings challenge the generalized assumption of unconditional colloid-facilitated transport, underscoring the importance of incorporating specific hydrogeochemical thresholds in the safety assessment of HLW geological disposal systems.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104858"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146010584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An efficient strategy of Bayesian optimized attention-enhanced LSTM surrogate model and its application in groundwater pump-and-treat remediation: A case study of a chromium-contaminated site in southern China","authors":"Yanhong Zou ,&nbsp;Fuqiang Yang ,&nbsp;Hao Deng ,&nbsp;Xiancheng Mao ,&nbsp;Yong He","doi":"10.1016/j.jconhyd.2025.104790","DOIUrl":"10.1016/j.jconhyd.2025.104790","url":null,"abstract":"<div><div>The simulation-optimization of pump-and-treat (PAT) systems for groundwater remediation often encounters significant computational demands due to the reliance on high-fidelity numerical models. Surrogate modeling has emerged as an effective strategy to mitigate this burden. However, a common limitation in existing studies is the oversimplification of temporal pumping dynamics through the assumption of uniform pumping durations, potentially leading to suboptimal and excessive pumping. To address this, we propose a novel surrogate modeling approach based on a Bayesian Optimization-enhanced Long Short-Term Memory network with an Attention mechanism (BO-LSTM-Attention). This methodology is applied to systematically optimize the PAT remediation strategy for a hexavalent chromium (Cr(VI)) contaminated site in southern China, treating the pumping rate, start time, and end time of each well as independent decision variables. By integrating attention-based temporal feature weighting and Bayesian hyperparameter optimization, the BO-LSTM-Attention surrogate model significantly enhances the predictive accuracy of Cr(VI) concentration on the test set, achieving a RMSE below 0.08, a MAE below 0.065, and a R² exceeding 0.99. Subsequently, the trained surrogate model was embedded into the multi-objective optimization framework to improve the existing uniform pumping scheme (680 m³/d) by simultaneously minimizing total pumping volume and maximizing restoration efficiency. The resulting optimized strategy yielded a 10 % reduction in the area exhibiting Cr(VI) concentrations above 80 mg/L and an average daily pumping reduction of 182.37 m³ over a one-year operational period, alongside a 96 % improvement in simulation-optimization computational efficiency. A two-year projection of the optimized strategy indicates the potential to reduce the maximum Cr(VI) concentration below 50 mg/L, with a substantial 62.5 % reduction in total extraction volume. These findings demonstrate that the BO-LSTM-Attention surrogate model concurrently enhances predictive accuracy and optimization efficiency, enabling coordinated control of high-concentration contaminant plumes and precise regulation of pumping operations. This approach offers an efficient and practical solution for groundwater remediation under complex hydrogeological conditions.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104790"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Competitive ligand control of Cu bioavailability: Decoupling anion (Cl−/SO42−/PO43−) versus fulvic acid regulation in speciation-phytotoxicity coupling","authors":"Xiaoqing Zhang ,&nbsp;Yujia Jiao ,&nbsp;Jiaxue Si ,&nbsp;Dajun Ren ,&nbsp;Shuqin Zhang","doi":"10.1016/j.jconhyd.2025.104806","DOIUrl":"10.1016/j.jconhyd.2025.104806","url":null,"abstract":"<div><div>The interactions between anions and dissolved organic matter play a crucial role in determining copper (Cu) bioavailability in soil environment. This study examined the impact of chloride (Cl⁻), sulfate (SO₄²⁻), phosphate (PO₄³⁻), and fulvic acid (FA) on soluble Cu speciation distribution, and phytotoxicity in barley root elongation. FA had a superior Cu²⁺-complexing ability, reducing the free Cu²⁺ content to 0.042 %–2.36 % through organic complexation (FA-Cu), which accounted for &gt;97.4 % of the total Cu. In contrast, anion treatments without FA primarily maintained soluble Cu as free ions with limited formation of inorganic complexes, with FA having the most significant effect, followed by PO₄³⁻, SO₄²⁻, and Cl⁻. The coexistence of FA and anions led to the emergence of competitive ligand interactions, with particularly pronounced variations in Cu speciation and complexation patterns observed. At low Cu, FA-Cu was the dominant soluble species, with free Cu²⁺ ≤ 31.50 %. Elevated Cu levels shifted speciation toward free Cu²⁺ and FA-Cu, except in systems with high PO₄³⁻-FA concentrations where PO₄³⁻ precipitates dominated. Furthermore, the single FA and co-coexistence of FA and anions of FA all increased the toxicity threshold (50 % inhibition, EC50) within a range of 2.8–12.4 folds, generally in the order of FA + Cl⁻ &lt; FA + SO₄²⁻ &lt; FA + PO₄³⁻, FA. It indicated that the protective effect of FA against Cu phytotoxicity was gradually weakened with the increasing addition of Cl⁻ and SO₄²⁻. This study provides important insights into the role of both organic and inorganic ligands in assessing Cu speciation and phytotoxicity in Cu-contaminated agroecosystems.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104806"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinguishing natural from mining-related metal sources by including streambank groundwater data in a stream mass loading study","authors":"Andrew H. Manning ,&nbsp;Robert L. Runkel ,&nbsp;Jean M. Morrison ,&nbsp;Sara Warix ,&nbsp;Richard B. Wanty ,&nbsp;Katherine Walton-Day ,&nbsp;Michael Snook","doi":"10.1016/j.jconhyd.2026.104841","DOIUrl":"10.1016/j.jconhyd.2026.104841","url":null,"abstract":"<div><div>Distinguishing stream metal loading caused by mine features from that caused by natural background sources remains challenging, yet this distinction is essential for making effective remedial decisions at many legacy mine sites. We combine a stream tracer injection and synoptic sampling study with data from shallow near-stream groundwater wells to estimate left-bank versus right-bank metal loading contributions at the 100-m spatial scale. The study was performed in the East Mancos River, a mountain headwater stream in Colorado, USA. The dominant source of elevated stream metal concentrations could be either groundwater infiltration through right-bank Doyle Mine waste piles or natural acid rock drainage from hydrothermally altered bedrock located mainly on the left bank. For the five metals of concern (Cu, Al, Zn, Cd, and Mn), we find that 15 % of the load contributed by diffuse groundwater inputs in the section potentially influenced by Doyle mine waste originates from the right bank. This right-bank potential mine contribution equates to only 3 % of the total watershed instream load for these metals. Furthermore, apparent ³H/³He groundwater ages in segments contributing most of the right-bank metal loading are sufficiently old (9–12 yr) to suggest that infiltration through the waste piles, located only 140–180 m from the stream, is unlikely. Estimated potential Doyle mine loading contributions can therefore be considered maximum values. Study results thus indicate that Doyle mine waste piles are a minor source of metal loading under low-flow conditions, and streambank groundwater data can provide valuable additional information in stream mass loading studies.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104841"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A multiple surrogate simulation-optimization framework for designing pump-and-treat systems","authors":"Chaoqi Wang ,&nbsp;Zhi Dou ,&nbsp;Ning Chen ,&nbsp;Yan Zhu ,&nbsp;Zhihan Zou ,&nbsp;Jian Song ,&nbsp;Shen-Huan Lyu","doi":"10.1016/j.jconhyd.2026.104876","DOIUrl":"10.1016/j.jconhyd.2026.104876","url":null,"abstract":"<div><div>Pump-and-treat (P&amp;T) remediation is a widely adopted and effective method for groundwater contamination control. It is important to optimize the operation schemes (pumping well locations and pumping rates) to maximize contaminant removal efficiency and minimize operational costs. Recently, surrogate models have been integrated with optimization algorithms to formulate the remediation schemes. However, with various surrogate techniques available, their comparative performance in P&amp;T remediation tasks and potential for combined usage of multiple surrogates require further exploration. In this study, five popular surrogate models—Kriging, Polynomial Interpolation, Support Vector Regression (SVR), Random Forest (RF), and Deep Neural Network (DNN)—were evaluated for their ability to predict contaminant removal efficiency under diverse schemes in a multi-contaminant site. The analysis revealed that, while DNN achieved the highest overall prediction accuracy in the validation stage across the 200 cases, no single surrogate model consistently outperformed the others in all individual cases. A multi-surrogate optimization framework, coupling all five models with a genetic algorithm, was developed to enhance P&amp;T schemes. The usage of multiple surrogates finally brings benefits because the complementary strengths of diverse surrogate models are combined. We identified remediation schemes that achieved superior contaminant removal (17.5% residual contaminant) compared to the other results (19.2–21.7%). The framework offers a robust tool for environmental management and insights for advancing studies related to surrogate-based optimization.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104876"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146137615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption of some hazardous aromatic hydrocarbons by various pristine and heat-activated aged microplastics as potential pollutant carriers in aquatic environment","authors":"Delaram-Sadat Tavoussi-Shirazi ,&nbsp;Kamand-Sadat Abdolhosseini ,&nbsp;Amir Hossein Hamidian ,&nbsp;Habib Bagheri","doi":"10.1016/j.jconhyd.2025.104817","DOIUrl":"10.1016/j.jconhyd.2025.104817","url":null,"abstract":"<div><div>Microplastics (MPs) are ubiquitous in terrestrial and aquatic ecosystems and persistent micropollutants of concern. Their persistence poses risks to ecosystems, human health, and organisms, while they can facilitate the migration and transformation of persistent organic pollutants by acting as vectors for their transportation into the environment and living organisms. This study examined the adsorption/desorption behavior of three nonpolar polycyclic aromatic hydrocarbons (pyrene, anthracene, and fluorene) on pristine and aged MPs, <em>i.e.</em>, polystyrene (PS), polyvinyl chloride (PVC), and polymethyl methacrylate (PMMA) through a series of batch adsorption experiments conducted under different pH values, contact times, and salinities. Results indicate that PS adsorbs higher amounts of PAHs than other MPs due to its rough surface, pores, and aromatic configuration strong π–π interactions. The PAHs adsorption followed a pseudo-second-order model, and fit best with the Freundlich isotherm due to multilayer adsorption. Aging with K₂S₂O₈ for 5 days enhanced adsorption on PMMA through surface roughening, reduced sorption on PVC due to oxidation, while PS exhibited minimal impact. The study examined PAHs desorption from MPs in fasted state simulated gastric fluid (FaSSGF), deionized water, and river water. (FaSSGF) showed the highest desorption rates, with pepsin enhancing desorption through micelle formation and weakening π-π interactions,. These findings highlight how organic pollutants are transported by both pristine and aged microplastics, and demonstrate the risk of desorption of these contaminants in aqueous and gastric environments, which may impact on ecosystems and human health.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104817"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of tetracycline adsorption by different embedded biochar materials","authors":"Chunming Wang,&nbsp;Anqi Zhao ,&nbsp;Meng Qi,&nbsp;Yi Jiang","doi":"10.1016/j.jconhyd.2025.104833","DOIUrl":"10.1016/j.jconhyd.2025.104833","url":null,"abstract":"<div><div>This study explored six novel biochar composite materials for adsorbing tetracycline antibiotics adsorption. These materials—namely, Bauhinia biochar, Bauhinia magnetic biochar, rice straw biochar, rice straw magnetic biochar, rice straw hydrothermal biochar, and rice straw hydrothermal magnetic biochar, were encapsulated with sodium alginate to form adsorption spheres. Results showed that magnetic biochar materials had higher adsorption capacities than non-magnetic ones, with rice straw magnetic biochar adsorption spheres showing the highest capacity at 3 mg/g. The isothermal adsorption of tetracycline by rice straw magnetic biochar adsorption spheres followed the Freundlich model, while the adsorption kinetics were best described by the pseudo-second-order model. The adsorption half-life was 3 h, and factors including biochar dosage, temperature, pH, and salinity affected the removal rate. SEM and FTIR analyses of rice straw hydrothermal magnetic biochar, rice straw magnetic biochar, and rice straw biochar revealed that rice straw biochar materials had a microporous structure mainly composed of C and O, while magnetic materials also contained significant amounts of iron. All three materials contained hydroxyl, alkene, alkyne, and alkyl functional groups. The increased Fe<img>O bonds in magnetic materials were the primary reason for the enhanced adsorption performance. Moreover, rice straw magnetic biochar adsorption spheres showed good reusability for high-concentration tetracycline. For low-concentration tetracycline, the adsorption capacity recovery exceeded 60 %, achieving an overall removal rate of over 80 %. Owing to their excellent recyclability and rapid adsorption rates, the rice straw magnetic biochar adsorption spheres hold significant potential in advanced wastewater treatment containing tetracycline antibiotics.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104833"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145878424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic biochar prepared by co-pyrolysis of sludge and organic medical solid waste for pH-universal removal of ciprofloxacin","authors":"Junping Meng ,&nbsp;Binbin Yao ,&nbsp;Jinsheng Liang ,&nbsp;Xinhui Duan ,&nbsp;Xiangying Wei","doi":"10.1016/j.jconhyd.2026.104862","DOIUrl":"10.1016/j.jconhyd.2026.104862","url":null,"abstract":"<div><div>In this study, sludge biochar was prepared via the co-pyrolysis method using the compatibility of sewage sludge (SS) in different seasons with organic medical solid waste (OMSW) and activated by alkali conditions for the removal of ciprofloxacin (CIP) in water with different pH values. The maximum adsorption capacity of the two biochars (KS1MBC and KS2MBC) reached 83.49 mg/g and 86.19 mg/g, respectively. The structure of the biochars was characterized via XRD, BET and SEM, and the adsorption mechanism of the biochars was investigated by FTIR, Raman, and XPS. The adsorption processes of the modified biochar followed pseudo-second-order kinetics and the Langmuir isothermal adsorption model, were dominated by chemical adsorption and monolayer adsorption, and were controlled by both liquid film diffusion and intraparticle diffusion. The adsorption mechanisms included pore adsorption, electrostatic attraction, π-π interactions, hydrogen bonding, and surface complexation. After hydrothermal activation by KOH, the surface of the biochar was etched by alkali to produce a nanothin lamellar structure, which increased the specific surface area to more than 200 m²/g in both cases, thus greatly enhancing the adsorption performance of the biochar. Moreover, due to the iron-containing properties of the sludge, it can be recycled through magnetic separation, thereby reducing treatment costs and enhancing the material's overall sustainability. The alkali-modified biochar demonstrates significant potential for application in antibiotic contamination remediation and provides a theoretical foundation for advancing waste treatment and promoting green environmental protection.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104862"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146022904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heavy metals in unsaturated urban soils: Experimental insights and stochastic forecasting","authors":"Aronne Dell'Oca ,&nbsp;Davide Abu El Khair ,&nbsp;Chiara Ferré ,&nbsp;Roberto Comolli ,&nbsp;Monica Riva","doi":"10.1016/j.jconhyd.2026.104855","DOIUrl":"10.1016/j.jconhyd.2026.104855","url":null,"abstract":"<div><div>The toxicity and long-term persistence of heavy metals pose a major threat across environmental compartments. Heavy metal contamination of soils poses long-term risks to groundwater resources, particularly in urban environments where rainfall-driven infiltration under unsaturated conditions can promote contaminant migration toward underlying aquifers. The aim of this study is to assess how uncertainty in soil hydraulic and sorption properties affects predictions of heavy metals migration from urban soils to groundwater. To this aim, we cast our work in a stochastic framework that integrates column scale drainage experiments and batch sorption tests to estimate key parameters governing water flow and heavy metal sorption dynamic, along with their associated uncertainty. Monte Carlo simulations are then performed to mimic the rainfall-induced drainage of heavy metals from metal-enriched soils through sewage sludge application. We consider two representative urban soil types and five heavy metals commonly detected in urban environments, i.e. lead (Pb), copper (Cu), chromium (Cr), nickel (Ni) and zinc (Zn). Our results indicate that Cr is highly mobile, while Ni, Zn, Cu exhibit consistently low mobility across both soils. Lead displays a strong soil-dependent behavior, transitioning from high to low mobility depending on the substrate. Outputs of a rigorous global sensitivity analysis reveal that, for highly mobile metals, flow and transport parameters have significant influence on metals migrations, reflecting the strong interplay of unsaturated flow and reactive transport processes. On the other hand, for low mobile heavy metals, parameters defining the initial contamination conditions and soil water content dominate the temporal evolution of metals retention in the soil. These findings indicate that parameter uncertainty and flow-transport processes in the vadose zone should be explicitly considered in groundwater contamination risk assessment protocols for urban environments.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104855"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146073939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}