Fate and Transport of Pathogens in the Subsurface

致病细菌和病毒对加拿大（CCME，2010）和世界各地（WHO，2006）的供水构成重大健康威胁。 病原体可以从化粪池系统、农业活动、污泥处理和受污染径流的渗透进入地下。在大多数情况下，病原体通过近地表的非饱和区到达饱和区。随后转移到供水威尔斯井可能对人类健康造成严重影响。细菌和病毒通过地下的运输是一个复杂的过程，受到细菌和病毒的物理化学性质以及地下环境的影响。尽管经过了几十年的研究，细菌和病毒在地下，特别是在非饱和带，以及在破碎的岩石和粘土中的迁移还没有得到很好的理解。 将进行实验室研究，以更好地了解细菌和病毒在地下，包括非饱和带、断裂岩石和粘土中的归宿和迁移。研究中将使用各种致病细菌和病毒的替代物。病原体特性，土壤性质，地球化学和生物膜的影响将使用孔隙尺度，一维和二维的实验室规模的系统结合原子力显微镜和石英晶体微天平研究。将开发用于预测多孔和裂缝介质中细菌和病毒的命运和运输的新的机械模型。这些模型将包括具有生物膜生长和病原体运输的微尺度模型格子玻尔兹曼流模型。将开发实地规模的模型，其中纳入实验研究和微型模型的结果。这项研究的结果可供加拿大监管机构和风险评估人员用于制定保护地下水资源免受病原体污染的综合政策。该项目将为培养3名博士生提供极好的机会。和3个硕士学生在一个跨学科的环境中，涉及水文地质学，微生物学，胶体化学和地球化学，在最先进的实验室和计算设施。

Pathogenic bacteria and viruses represent significant health threats to water supplies in Canada (CCME, 2010) and around the world (WHO, 2006). Pathogens can enter the subsurface from septic systems, agricultural activities, sludge disposal, and infiltration of contaminated runoff. In most cases, pathogens travel through the near surface unsaturated zone, to the saturated zone. Subsequent transport to water supply wells can lead to serious impacts on human health. Transport of bacteria and viruses through the subsurface is a complex process, influenced by the physicochemical nature of the bacteria and viruses and of the subsurface environment. In spite of decades of study, transport of bacteria and viruses in the subsurface, particularly in the unsaturated zone, and in fractured rock and clay is not well understood. Laboratory studies will be conducted to improve the understanding of the fate and transport of bacteria and viruses in the subsurface, including the unsaturated zone, and fractured rock and clay. A variety of surrogates for pathogenic bacteria and viruses will be used in the studies. The effects of pathogen characteristics, soil properties, geochemistry, and biofilms will be examined using pore scale, and one and two dimensional bench scale systems in combination with atomic force microscopy and quartz crystal microbalance studies. New mechanistic models for predicting the fate and transport of bacteria and viruses in porous and fractured media will be developed. These models will include a microscale model Lattice Boltzmann flow model with biofilm growth and pathogen transport. Field scale models will be developed that incorporate the results of experimental studies and microscale modelling. The results of this research can be used by Canadian regulators and risk assessors in developing comprehensive policies for protection of subsurface water resources from contamination by pathogens. leading to improved protection of the health of the Canadian public.The project will provide excellent opportunities for training the 3 Ph.D. and 3 M.A.Sc. students in an interdisciplinary environment involving hydrogeology, microbiology, colloidal chemistry and geochemistry, in state of the art laboratory and computational facilities.