Soil vapor extraction (SVE) is effective for removing volatile organic compound (VOC) mass from the vadose zone and reducing the potential for vapor intrusion (VI) into overlying and surrounding buildings. However, the relationship between residual mass in the subsurface and VI is complex. Through a series of alternating extraction (SVE on) and rebound (SVE off) periods, this field study explored the relationship and aspects of SVE applicable to VI mitigation in a commercial/light‐industrial setting. The primary objective was to determine if SVE could provide VI mitigation over a wide area encompassing multiple buildings, city streets, and subsurface utilities and eliminate the need for individual subslab depressurization systems. We determined that SVE effectively mitigates offsite VI by intercepting or diluting contaminant vapors that would otherwise enter buildings through foundation slabs. Data indicate a measurable (5 Pa) influence of SVE on subslab/indoor pressure differential may occur but is not essential for effective VI mitigation. Indoor air quality improvements were evident in buildings 100 to 200 feet away from SVE including those without a measurable reversal of differential pressure across the slab or substantial reductions in subslab VOC concentration. These cases also demonstrated mitigation effects across a four‐lane avenue with subsurface utilities. These findings suggest that SVE affects distant VI entry points with little observable impact on differential pressures and without relying on subslab VOC concentration reductions.

中文翻译：

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土壤蒸气提取减少场外蒸气入侵的现场研究

土壤蒸气提取（SVE）可有效去除渗流带中的挥发性有机化合物（VOC）物质，并减少蒸气入侵（VI）进入上覆和周围建筑物的可能性。但是，地下残余质量与VI之间的关系很复杂。通过一系列交替的提取（SVE开启）和反弹（SVE断开）阶段，该现场研究探索了适用于商业/轻工业环境下VI缓解的SVE的关系和方面。主要目标是确定SVE是否可以在涵盖多个建筑物，城市街道和地下公用设施的广阔区域内提供VI缓解，并消除对单个地下减压系统的需求。我们确定SVE通过拦截或稀释本来会通过地基板进入建筑物的污染物蒸汽来有效缓解异地VI。数据表明，SVE对底板/室内压差可能产生可测量的（5 Pa）影响，但对于有效缓解VI而言并非必需。在距离SVE 100到200英尺的建筑物中，室内空气质量得到了明显改善，包括那些没有可测量的整个板间压差反转或下板VOC浓度大幅降低的建筑物。这些案例还证明了利用地下公用设施跨越四车道的缓解效果。这些发现表明，SVE影响远处的VI入口点，而对压差几乎没有可观察到的影响，并且不依赖于底板VOC浓度的降低。