Sources of Radium Accumulation in Stream Sediments near Disposal Sites in Pennsylvania: Implications for Disposal of Conventional Oil and Gas Wastewater.
Sources of Radium Accumulation in Stream Sediments near Disposal Sites in Pennsylvania: Implications for Disposal of Conventional Oil and Gas Wastewater.
复制标题
宾夕法尼亚州处置场附近溪流沉积物中镭积累的来源：对传统石油和天然气废水处置的影响。
DOI：
10.1021/acs.est.7b04952
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发表时间：
2018
影响因子：
11.4
通讯作者：
A. Vengosh
中科院分区：
文献类型：
--
作者：
Nancy E. Lauer;N. Warner;A. Vengosh
在宾夕法尼亚州，阿巴拉契亚的石油和天然气废水沃茨（OGW）在经过集中废物处理（CWT）设施的一些处理后，允许释放到地表沃茨。虽然2011年在允许释放高盐度流出物的设施中对非常规Marcellus OGW基本停止了这种做法，但对常规OGW仍在继续。本研究旨在评估允许处置常规OGW的政策对环境的影响。我们收集了2014年至2017年接受处理过的OGW的三个处置场的河流沉积物，并分别测量了228 Ra，226 Ra及其衰变产物228 Th和210 Pb。我们一直发现，与上游沉积物（20-80 Bq/kg）相比，排放口附近的河流沉积物中228 Ra和226 Ra的放射性较高（总Ra = 90- 25，000 Bq/kg）。2015年和2017年，两个处置场沉积物中的228 Th/228 Ra活度比值相对较低（0.2-0.7），表明近（<3）年来沉积物中积累了一部分Ra，当时没有报告非常规Marcellus OGW排放。228 Ra/226 Ra放射性比率也高于仅处置低228 Ra/226 Ra Marcellus OGW所预期的比率。基于这些变化，我们得出的结论是，最近处置处理过的传统OGW的来源，高Ra的河流沉积物在CWT设施处置地点。因此，仅处置非常规流体的政策不足以防止处置场沉积物中的放射性污染，应重新考虑允许通过CWT设施释放处理过的富Ra常规OGW。
In Pennsylvania, Appalachian oil and gas wastewaters (OGW) are permitted for release to surface waters after some treatment by centralized waste treatment (CWT) facilities. While this practice was largely discontinued in 2011 for unconventional Marcellus OGW at facilities permitted to release high salinity effluents, it continues for conventional OGW. This study aimed to evaluate the environmental implications of the policy allowing the disposal of conventional OGW. We collected stream sediments from three disposal sites receiving treated OGW between 2014 and 2017 and measured 228Ra, 226Ra, and their decay products, 228Th and 210Pb, respectively. We consistently found elevated activities of 228Ra and 226Ra in stream sediments in the vicinity of the outfall (total Ra = 90-25,000 Bq/kg) compared to upstream sediments (20-80 Bq/kg). In 2015 and 2017, 228Th/228Ra activity ratios in sediments from two disposal sites were relatively low (0.2-0.7), indicating that a portion of the Ra has accumulated in the sediments in recent (<3) years, when no unconventional Marcellus OGW was reportedly discharged. 228Ra/226Ra activity ratios were also higher than what would be expected solely from disposal of low 228Ra/226Ra Marcellus OGW. Based on these variations, we concluded that recent disposal of treated conventional OGW is the source of high Ra in stream sediments at CWT facility disposal sites. Consequently, policies pertaining to the disposal of only unconventional fluids are not adequate in preventing radioactive contamination in sediments at disposal sites, and the permission to release treated Ra-rich conventional OGW through CWT facilities should be reconsidered.