Roghani Mahammadyousef, Li Ying, Rezaei Nader, Robinson Ariel, Shirazi Elham, Pennell Kelly G
University of Kentucky, College of Engineering, Department of Civil Engineering.
Ground Water Monit Remediat. 2021 Spring;41(2):112-121. doi: 10.1111/gwmr.12449. Epub 2021 Apr 12.
Hazardous waste site investigations have shown that volatile organic compounds (VOCs) can be transported via sewer pipes and migrate into indoor spaces. Despite field data confirming the presence of this exposure pathway, there is lack of context-based numerical models that provide guidance to characterize and predict VOCs concentration in sewer gas at vapor intrusion sites. Particularly, this poses a challenge when assessing and mitigating risks associated with these exposure pathways. Therefore, a numerical model has been developed to simulate the concentration of VOCs in sewer gas in different stages throughout the sewer lines. The developed model considers various input parameters, including temperature, sewer liquid depth, groundwater depth, and sewer construction characteristics to incorporate local and operational conditions. The model's output is verified using field data from a sewer system constructed near a Superfund site. Moreover, a sensitivity analysis was conducted to evaluate the model's response to variation of the external input parameters. To the best of our knowledge, this study is the first attempt to model VOCs concentration in sewer gas, particularly to address vapor intrusion. The developed model can be used as a numerical tool to support the development of sewer assessment guidelines, risk assessment studies, and mitigation strategies.
危险废物场地调查表明，挥发性有机化合物（VOCs）可通过下水道管道传输并迁移到室内空间。尽管现场数据证实了这种暴露途径的存在，但缺乏基于实际情况的数值模型来指导对蒸汽入侵场地下水道气体中VOCs浓度进行表征和预测。特别是，在评估和减轻与这些暴露途径相关的风险时，这构成了一项挑战。因此，已开发出一个数值模型，用于模拟整个下水道系统不同阶段下水道气体中VOCs的浓度。所开发的模型考虑了各种输入参数，包括温度、下水道液位深度、地下水位深度以及下水道建设特征，以纳入当地和运行条件。该模型的输出结果通过一个在超级基金场地附近建造的下水道系统的现场数据进行了验证。此外，还进行了敏感性分析，以评估该模型对外部输入参数变化的响应。据我们所知，本研究是首次尝试对下水道气体中的VOCs浓度进行建模，特别是针对蒸汽入侵问题。所开发的模型可作为一种数值工具，以支持下水道评估指南、风险评估研究和缓解策略的制定。
