The potential for in situ biodegradation of tert-butyl alcohol (TBA) by creation of aerobic conditions in the subsurface with recirculating well pairs was investigated in two field studies conducted at Vandenberg Air Force Base (VAFB). In the first experiment, a single recirculating well pair with bromide tracer and oxygen amendment successfully delivered oxygen to the subsurface for 42 days. TBA concentrations were reduced from approximately 500 μg/L to below the detection limit within the treatment zone and the treated water was detected in a monitoring transect several meters downgradient. In the second experiment, a site-calibrated model was used to design a double recirculating well pair with oxygen amendment, which successfully delivered oxygen to the subsurface for 291 days and also decreased TBA concentrations to below the detection limit. Methylibium petroleiphilum strain PM1, a known TBA-degrading bacterium, was detectable at the study site but addition of oxygen had little impact on the already low baseline population densities, suggesting that there was not enough carbon within the groundwater plume to support significant new growth in the PM1 population. Given favorable hydrogeologic and geochemical conditions, the use of recirculating well pairs to introduce dissolved oxygen into the subsurface is a viable method to stimulate in situ biodegradation of TBA or other aerobically-degradable aquifer contaminants.

中文翻译：

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使用再循环/氧化对 TBA 进行原位生物处理。

在范登堡空军基地 (VAFB) 进行的两项实地研究中，研究了通过使用循环井对在地下创造有氧条件来原位生物降解叔丁醇 (TBA) 的潜力。在第一个实验中，一对带有溴化物示踪剂和氧气修正剂的循环井成功地将氧气输送到地下 42 天。TBA 浓度从大约 500 μg/L 降低到处理区内的检测限以下，并且在几米下坡的监测断面中检测到处理过的水。在第二个实验中，使用现场校准模型设计了一个带有氧气修正的双循环井对，它成功地将氧气输送到地下 291 天，并将 TBA 浓度降低到检测限以下。在研究地点可检测到 Methylibium petroleiphilum 菌株 PM1，一种已知的 TBA 降解细菌，但添加氧气对已经很低的基线人口密度几乎没有影响，这表明地下水羽中没有足够的碳来支持显着的新生长PM1 人口。鉴于有利的水文地质和地球化学条件，使用循环井对将溶解氧引入地下是刺激 TBA 或其他需氧可降解含水层污染物原位生物降解的可行方法。表明地下水羽流中没有足够的碳来支持 PM1 种群的显着新增长。鉴于有利的水文地质和地球化学条件，使用循环井对将溶解氧引入地下是刺激 TBA 或其他需氧可降解含水层污染物原位生物降解的可行方法。表明地下水羽流中没有足够的碳来支持 PM1 种群的显着新增长。鉴于有利的水文地质和地球化学条件，使用循环井对将溶解氧引入地下是刺激 TBA 或其他需氧可降解含水层污染物原位生物降解的可行方法。