Department of Soil, Water and Environmental Science, The University of Arizona, Tucson, AZ, United States.
Chair Quantitative Microbial Water Safety, Environmental Hydrogeology Group, Faculty of Geosciences, Utrecht University, The Netherlands.
J Contam Hydrol. 2019 Jun;223:103479. doi: 10.1016/j.jconhyd.2019.04.002. Epub 2019 Apr 10.
Reduction of viral surrogates (bacteriophage MS2 and murine norovirus-1 [MNV-1]) and viruses naturally present in wastewater (enteroviruses, adenoviruses, Aichi viruses, reovirus, pepper mild mottle virus) was studied in a long-term experiment simulating soil-aquifer treatment of a non-disinfected secondary treated wastewater effluent blend using a 4.4 m deep saturated soil column (95% sand, 4% silt, 1% clay) with a hydraulic residence time of 15.4 days under predominantly anoxic redox conditions. Water samples were collected over a four-week period from the column inflow and outflow as well as from seven intermediate sampling ports at different depths. Removal of MS2 was 3.5 log over 4.4 m and removal of MNV-1 was 3 log over 0.3 m. Notably, MNV-1 was removed to below detection limit within 0.3 m of soil passage. In secondary treated wastewater effluent, MNV-1 RNA and MS2 RNA degraded at a first-order rate of 0.59 day and 0.12 day, respectively. In 15.4 days, the time to pass the soil column, the RNA-degradation of MS2 would amount to 0.8 log and in one day that of MNV-1 0.3 log implying that attachment of MNV-1 and MS2 to the sandy soil took place. Among the indigenous viruses, genome copies reductions were observed for Aichi virus (4.9 log) and for pepper mild mottle virus (4.4 log). This study demonstrated that under saturated flow and predominantly anoxic redox conditions MS2 removal was non-linear and could be described well by a power-law relation. Pepper mild mottle virus was removed less than all of the other viruses studied, which substantiates field studies at managed aquifer recharge sites, suggesting it may be a conservative model/tracer for enteric virus transport through soil.
本研究采用长时实验模拟了非消毒二级处理出水与混合污水在土壤-含水层中的处理过程，使用一个 4.4m 深的饱和土壤柱（95%的砂、4%的粉土和 1%的粘土），水力停留时间为 15.4 天，主要处于缺氧氧化还原条件下。在四周的时间内，从土壤柱的进水口和出水口以及七个不同深度的中间采样口采集水样。在 4.4m 深度范围内，MS2 的去除率为 3.5 个对数，而在 0.3m 深度范围内，MNV-1 的去除率为 3 个对数。值得注意的是，MNV-1 在通过 0.3m 土壤后被去除到检测限以下。在二级处理废水中，MNV-1 RNA 和 MS2 RNA 的降解遵循一级动力学，分别为 0.59 天和 0.12 天。在 15.4 天的时间内，通过土壤柱的时间，MS2 的 RNA 降解量将达到 0.8 个对数，而在一天内，MNV-1 的 RNA 降解量为 0.3 个对数，这表明 MNV-1 和 MS2 附着在沙质土壤上。在本地病毒中，观察到 Aichi 病毒（4.9 个对数）和胡椒温和斑点病毒（4.4 个对数）的基因组拷贝减少。本研究表明，在饱和流和主要缺氧氧化还原条件下，MS2 的去除是非线性的，可以用幂律关系很好地描述。胡椒温和斑点病毒的去除率低于研究的所有其他病毒，这证实了管理含水层补给点的现场研究，表明它可能是一种保守的模型/示踪剂，用于肠道病毒通过土壤的传输。
