Bugna G C, Chanton J P, Stauffer T B, MacIntyre W G, Libelo E L
Department of Oceanography, Florida State University, Tallahassee, FL 32306-4320, USA.
Chemosphere. 2005 Jul;60(2):177-87. doi: 10.1016/j.chemosphere.2004.12.066.
The relative importance of jet fuel biodegradation relative to the respiration of natural organic matter in a contaminated organic-rich aquifer underlying a fire training area at Tyndall Air Force Base, Florida, USA was determined with isotopic measurements. Thirteen wells were sampled and analyzed for BTX (benzene, toluene, xylene), dissolved inorganic carbon (DIC) and CH4 concentrations, and delta13C and 14C of DIC. Results range from non-detectable to 3790 ppb, 1.4-24 mM, 0.2-776 microM, +5.8 per thousand to -22 per thousand, and from 52 to 99 pmc, respectively. Residual fuel was confined to two center wells underlying the fire training area. DIC and CH4 concentrations were elevated down-gradient of the contamination, but also at sites that were not in the apparent flow path of the contaminated groundwater. DIC exhibited greatest delta13C enrichment at highest DIC and CH4 concentrations indicating that CH4 production was an important respiration mode. Radiocarbon-depleted DIC was observed at sites with high hydrocarbon concentrations and down-gradient of the site. The results indicate that while natural attenuation was not rapidly reducing the quantity of free product overlying the aquifer at the site of contamination, it was at least constraining its flow away from the spill site. Apparently under the conditions of this study, BTX was degraded as rapidly as it was dissolved.
通过同位素测量确定了在美国佛罗里达州廷德尔空军基地一个火灾训练区域下方受污染的富含有机物含水层中，喷气燃料生物降解相对于天然有机物呼吸作用的相对重要性。采集了13口井的样本，分析了其中的BTX（苯、甲苯、二甲苯）、溶解无机碳（DIC）和CH₄浓度，以及DIC的δ¹³C和¹⁴C。结果分别为未检测到至3790 ppb、1.4 - 24 mM、0.2 - 776 μM、+5.8‰至 - 22‰，以及52至99 pmc。残留燃料局限于火灾训练区域下方的两口中心井。DIC和CH₄浓度在污染的下游升高，但在未处于受污染地下水明显流动路径的地点也升高。在最高DIC和CH₄浓度时，DIC表现出最大的δ¹³C富集，表明CH₄生成是一种重要的呼吸模式。在高碳氢化合物浓度的地点及其下游观察到放射性碳贫化的DIC。结果表明，虽然自然衰减没有迅速减少污染场地含水层上方游离产物的数量，但至少限制了其从泄漏点流出。显然在本研究条件下，BTX溶解后降解速度很快。
