Groundwater contamination caused by Dense Non-Aqueous Phase Liquid (DNAPL) has an adverse impact on human health and environment. Remediation techniques, such as the in-situ injection of nano Zero Valent Iron (nZVI) particles, are widely used in mitigating DNAPL-induced groundwater contamination. However, an effective remediation strategy requires predictive insights and understanding of the physiochemical interaction of nZVI and contamination along with the porous media properties. While several stand-alone models are widely used for predictive modeling, the integration of these models for better scalability and accuracy is still rarely utilized. This study presents an end-to-end integrated modeling framework for the remediation of DNAPL-contaminated aquifers using nZVI. The framework simulates the migration pathway of DNAPL and subsequently its dissolution in groundwater resulting in an aqueous contaminant plume. Additionally, the framework includes simulations of nZVI mobility, transport, and reactive behavior, allowing for the prediction of the radius of influence and efficiency of nZVI for contaminant degradation. The framework has been applied to a hypothetical 2-dimensional and heterogeneous silty sand aquifer, considering trichloroethylene (TCE) as the DNAPL contaminant and carboxymethyl cellulose (CMC) coated nZVI for remediation. The results demonstrate the framework's capability to provide comprehensive insights into the contaminant's behavior and the effectiveness of the remediation strategy. The proposed modeling framework serves as a reference for future studies and can be expanded to incorporate real field data and complex geometries for upscaled applications.

翻译：由重质非水相液体（DNAPL）引起的地下水污染对人类健康和环境产生不利影响。诸如原位注入纳米零价铁（nZVI）颗粒等修复技术被广泛用于减轻DNAPL诱导的地下水污染。然而，有效的修复策略需要预测性见解和对nZVI与污染物之间物理化学相互作用及多孔介质特性的理解。尽管多种独立模型广泛用于预测建模，但这些模型为实现更好可扩展性与准确性的集成仍鲜有应用。本研究提出了一种利用nZVI修复DNAPL污染含水层的端到端集成建模框架。该框架模拟DNAPL的迁移路径及其随后在地下水中的溶解过程，从而形成含水污染物羽流。此外，该框架包含nZVI流动性、传输和反应行为的模拟，可预测nZVI的波及半径及其对污染物降解的效率。将本框架应用于一个假设的二维非均质粉砂含水层，以三氯乙烯（TCE）作为DNAPL污染物，并使用羧甲基纤维素（CMC）包覆的nZVI进行修复。结果表明，该框架能够全面洞察污染物行为及修复策略的有效性。所提出的建模框架可作为未来研究的参考，并可扩展以纳入真实现场数据和复杂几何结构，用于规模化应用。