期刊
SCIENCE OF THE TOTAL ENVIRONMENT
卷 755, 期 -, 页码 -出版社
ELSEVIER
DOI: 10.1016/j.scitotenv.2020.142909
关键词
Unconventional oil and gas production; Wastewaters; Brine spills; Tight oil production; Williston Basin; Bakken formation; Transport pathways; Tracers
资金
- U.S. Geological Survey (USGS) Environmental Health Program
- USGS Energy Resources Program
- USGS Fisheries Program
Releases of oil and gas wastewaters can have complex and persistent effects on stream-water quality and downstream organisms, influencing hydrologic conditions and ecological impacts. Contaminants from spills can persist in sediments and pore water, with variable concentrations depending on hydrologic conditions. Geomorphic investigations suggest that sediment mobilization is a significant contaminant transport process.
Releases of oil and gas (OG) wastewaters can have complex effects on stream-water quality and downstream organisms, due to sediment-water interactions and groundwater/surface water exchange. Previously, elevated concentrations of sodium (Na), chloride (Cl), barium (Ba), strontium (Sr), and lithium (Li), and trace hydrocarbons were determined to be key markers of OG wastewater releases when combined with Sr and radium (Ra) isotopic compositions. Here, we assessed the persistence of an OG wastewater spill in a creek in North Dakota using a combination of geochemical measurements and modeling, hydrologic analysis, and geophysical investigations. OG wastewater comprised 0.1 to 0.3% of the stream-water compositions at downstream sites in February and June 2015 but could not be quantified in 2016 and 2017. However, OG-wastewater markers persisted in sediments and pore water for 2.5 years after the spill and up to 7.2-km downstream from the spill site. Concentrations of OG wastewater constituents were highly variable depending on the hydrologic conditions. Electromagnetic measurements indicated substantially higher electrical conductivity under the bank adjacent to a seep 7.2 km downstream from the spill site. Geomorphic investigations revealed mobilization of sediment is an important contaminant transport process. Labile Ba, Ra, Sr, and ammonium(NH4) concentrations extracted from sediments indicated sediments are a long-term reservoir of these constituents, both in the creek and on the floodplain. Using the drivers of ecological effects identified at this intensively studied sitewe identified 41 watersheds across the North Dakota landscape that may be subject to similar episodic inputs from OG wastewater spills. Effects of contaminants released to the environment during OG waste management activities remain poorly understood; however, analyses of Ra and Sr isotopic compositions, as well as trace inorganic and organic compound concentrations at these sites in pore-water provide insights into potentials for animal and human exposures well outside source-remediation zones. (C) 2020 The Authors. Published by Elsevier B.V.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据