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年度	109	專案性質	非實驗性質
專案類別	研究專案	研究主題	自訂
申請機構	國立中央大學	申請系所	應用地質研究所
專案主持人	陳瑞昇	職等/職稱	教授
專案中文名稱	發展結合污染源區與溶解相污染團的含氯有機溶劑地下水污染整治評估模式
中文關鍵字	污染源區,污染團,整治,含氯有機溶劑,解析解模式,癌症,健康風險評估
專案英文名稱	Remediation evaluation model of for groundwater contaminated with chlorinated solvents
英文關鍵字	source zone, plume, remediation, chlorinated solvent, analytical model, cancer, health risk assessment
執行金額	1,067,738元
執行期間	2020/1/1 至 2020/12/31
計畫中文摘要	REMChlor為可以同時考慮含氯有機溶劑地下水污染的污染源區與溶解相污染團整治的篩選級別的解析解模式。美國環保署地下環境模式支援中心發展出REMChlor的圖形使用者介面，方便使用者能輕易操作並快速地執行計算。REMChlor因為它的解析解的基礎為Domenico的近似解析解，因此不能應用於含水層有大的縱向延散係數值。再者，因為REMChlor用來分離模式中的互相耦合偏微分方程式的除耦技巧使得REMChlor只能適用所有含氯有機溶劑物種具有相同的遲滯因子值。本專案目標為發展出一個可以同時結合污染源區以及溶解相污染團整治的評估模式，此模式可適用大的縱向延散係數值與每一個含氯有機溶劑物種可以有不同的遲滯因子值的限制。污染源區整治模式考慮污染源DNAPL質量的溶解作用以及污染源整治清除與破壞所造成之一階衰減反應。污染源區整治模式將耦合至溶解相污染團整治模式，溶解相污染團整治模式考慮的傳輸機制包括一維的移流、三維的水力延散、由母物種至其子物種產物的一階序列衰減反應的質量貢獻與線性平衡等溫吸附等機制過程。所發展的解析解模式主要是藉由三個積分轉換法與求解二階常微分方程式的數學方法依序求解一組由序列衰減反應耦合的偏微分傳輸方程式。解析解與其計算FORTRAN程式的正確性與準確性經與文獻中的解析解比較，結果顯示兩者非常的吻合，可以確認解的正確性。本研究所發展的解析解模式評估REMChlor的適用性發現可能會有高估或低估污染物的移動性。所發展的整治應用於台灣北部含氯有機溶劑地下水污染場址展現模式模擬結果與現地觀測資料有一致的趨勢，而且模式與現地資料所得的TCE、DCE與VC分別有不同的遲滯因子也顯示REMChlor假設每一個污染物有相同遲滯因子的不合理，另外也藉由比較熱區有整治與無整治，說明在地下水流污染熱區整治的重要性。結合整治評估數學模式與致癌健康風險評估模式進行了含氯有機溶劑地下水污染場址的健康風險評估說明了有進行污染源熱區整治下，在600天後相對於無整治熱區可降低健康風險達1,000倍。
計畫英文摘要	The REMChlor is a screen-level analytical model that is widely used for simulating the transient effects of coupled source and dissolved plume remediation of groundwater contaminated with chlorinated solvents. The Center for Subsurface Modeling Support (CSMoS) at USEPA has developed a Graphical User Interface (GUI) for REMChlor that facilitates the user to quickly and easily execute the calculation. The analytical solution embedded in the REMChlor was derived based on the Domenico’s approxi-mate analytical solution and is invalid for large longitudinal dispersion coefficients. Moreover, the decomposition method used for separating a set of coupled partial dif-ferential equations leads that REMChlor analytical solutions are only valid for each individual species having identical retardation factor. In this the project, we target to propose a novel analytical model that couples source and dissolved plume remediation of groundwater contaminated with chlorinated solvents. The newly derived model will be valid for large dispersion coefficient and different retardation factors for each indi-vidual species. The source model accounts for depletion of mass by processes of dis-solution and first-order decay reactions resulting from removal or destruction of source mass by remediation. The source model will be coupled to a plume remediation model that considers 1-D advection, 3-D dispersion, first-order decay reaction of par-ent compound into daughter product and linear isothermal equilibrium sorption. The analytical solutions will be obtained using three integral transformation techniques in combination with the mathematical method for solving second-order ordinary differen-tial equations in sequence. The correctness of the mathematical model and its auxiliary FORTRAN computer program code is established with excellent agreement between the derived novel analytical model and two analytical models available in the litera-ture. The evaluation of REMChlor performance shows that REMChlor can predict lower and higher concentrations than our developed model. The developed model is applied to assess the transport parameters of a contaminated site where bioremediation was executed. Our developed model predicts the similar trend of concentrations of TCE, DCE and VC at a monitoring well. The estimated retardation factors for TCE, DCE and are 4, 11 and 9, respectively, implying that the assumption of each individual spe-cies having identical retardation factor is unreasonable. Ultimately, the derived novel analytical model coupled with the health risk assessment model for calculation of risk posed carcinogenic species is applied to estimate the health risk for with/without re-mediation. The result shows that the remediation of the hotspot area can reduce the health risk up to three orders after 600 days compare to the hotspot area without reme-diation.