含氯溶劑地下水污染為全球非常重要的環境議題。含氯溶劑即使在低濃度下也被認為是致癌物和有毒物質。此類污染物很難整治，主要因為它們通常以重質非水相液體(DNAPL)的形式外釋。監測式自然衰減(MNA)指包括各種物理、化學或生物機制的自然衰減過程，在適當的條件下，無需人為的方式，可減少污染物的質量、毒性、遷移性、體積或濃度。在含氯溶劑污染場址，MNA 為有效方法，因為自然衰減過程會破壞和降解污染物。使用 MNA 的決策須有場址資料和分析支持。為了評估 MNA 含水層整治措施的有效性，需要有長期的監測計畫。MNA的有效性在於要保護環境安全和公眾健康。數學模型廣泛應用於這些含氯溶劑污染場地。轉化產物的形成和降解對於含氯溶劑污染物傳輸非常重要。多物種傳輸解析解式以數學求解了一組由一系列一階降解反應耦合聯立移流-延散方程式，可同時合理地預測原始汙染物及其生成產物的傳輸。在多物種傳輸解析解模式中，美國環保署所提供的BIOCHLOR和REMChlor是最常用的模式。基於健康風險的整治是管理污染場址的另一種方法。健康風險評估結合傳輸模式和健康風險評估工具來計算地下水污染對人類健康的影響。近年來，我們開發了幾個先進的多物種傳輸解析解模式發表於頂尖期刊。本計畫的目標是開發一個軟體可用於評估地下水含氯化溶劑污染場址的MNA和健康風險。計畫將完成三項重要工作。工項一將開發場地管理模組，用於管理和空間繪製有關地質、水文和污染的場址資料以及建立概念場址模型 (CSM)。工項二將開發 MNA 評估模組，主要是藉由於我們先進的多物種傳輸解析解模式的 FORTRAN 執行檔配備了互動式圖形使用者介面 (GUI)。工項三將建立健康風險評估模組，將我們的先進多物種傳輸解析解模式與健康風險模式結合，用於計算致癌和非致癌健康風險。新開發的軟體將為評估 MNA 和健康風險的有效工具。 ;Groundwater contaminated by chlorinated solvents is an environmental issue of great importance globally. Chlorinated solvents are recognized as carcinogens and toxicants, even at low concentration levels. Such contaminations are challenging to restore because they are often released as dense non-aqueous phase liquids (DNAPLs). Monitored natural attenuation (MNA) refers to the natural attenuation processes that include a variety of physical, chemical or biological mechanisms, under favorable conditions, acts to reduce the mass, toxicity, mobility, volume or concentration of contaminants without human intervention. At chlorinated solvent contaminated sites, MNA is most effective where the natural attenuation processes destroy and degrade contaminants. Decisions to use MNA are supported by site-specific data as well as analysis. A long-term monitoring plan is necessary to evaluate the effectiveness of MNA aquifer remedy. For an MNA to effective, it must be protective of safety of environment and public health. Mathematical models are widely used at these chlorinated solvent contaminated sites. The formation and degradation of these transformation products can be crucial in the transport of chlorinated solvent contaminant. Multispecies transport analytical models in which a set of simultaneous advection-dispersion equations coupled with a series of first-order degradation reactions are mathematically solved have been developed for synchronously and reasonably predicting the transport of the parent compound and its daughter products. Among the multispecies transport analytical models, BIOCHLOR and REMChlor provided by USEPA are the most commonly used models. Health risk-based remediation is an alternative approach for managing contaminated sites. Health risk assessment combines transport models and health risk assessment tools to calculate the impact of groundwater contamination on human health. Most recently, we have developed a couple of advanced multispecies transport analytical models and published them in the prestigious journals. In this project, we target to develop a software package for assessing MNA and health risk at groundwater chlorinated solvent contaminated sites. Three important tasks will be completed. Task 1 will develop a site management module for managing and spatially mapping site-specific data regarding geology, hydrology and contamination and conceptual site model (CSM). Task 2 will develop an MNA assessment module in which FORTRAN executable files based on our advanced multispecies transport analytical models are equipped with an interactive Graphical User Interface (GUI). Task 3 will build a health risk assessment module that combined our advanced multispecies transport analytical models with health risk model for calculating carcinogenic and noncarcinogenic health risks. The newly developed software package will be an effective tool for assessing and MNA and health risk.
