TY - JOUR
T1 - Detecting the effects of coal mining, acid rain, and natural gas extraction in Appalachian basin streams in Pennsylvania (USA) through analysis of barium and sulfate concentrations
AU - Niu, Xianzeng
AU - Wendt, Anna
AU - Li, Zhenhui
AU - Agarwal, Amal
AU - Xue, Lingzhou
AU - Gonzales, Matthew
AU - Brantley, Susan L.
N1 - Funding Information:
Acknowledgements This work was funded from a gift to Penn State for the Pennsylvania State University General Electric Fund for the Center for Collaborative Research on Intelligent Natural Gas Supply Systems. The Shale Network database has been funded by the National Science Foundation RCN-SEES funding (OCE-11-40159), by Penn State, and by the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI). This work is also partially funded by National Science Foundation Grants DMS-1505256 and IIS-1639150.
Publisher Copyright:
© 2017, Springer Science+Business Media B.V.
PY - 2018/4/1
Y1 - 2018/4/1
N2 - To understand how extraction of different energy sources impacts water resources requires assessment of how water chemistry has changed in comparison with the background values of pristine streams. With such understanding, we can develop better water quality standards and ecological interpretations. However, determination of pristine background chemistry is difficult in areas with heavy human impact. To learn to do this, we compiled a master dataset of sulfate and barium concentrations ([SO4], [Ba]) in Pennsylvania (PA, USA) streams from publically available sources. These elements were chosen because they can represent contamination related to oil/gas and coal, respectively. We applied changepoint analysis (i.e., likelihood ratio test) to identify pristine streams, which we defined as streams with a low variability in concentrations as measured over years. From these pristine streams, we estimated the baseline concentrations for major bedrock types in PA. Overall, we found that 48,471 data values are available for [SO4] from 1904 to 2014 and 3243 data for [Ba] from 1963 to 2014. Statewide [SO4] baseline was estimated to be 15.8 ± 9.6 mg/L, but values range from 12.4 to 26.7 mg/L for different bedrock types. The statewide [Ba] baseline is 27.7 ± 10.6 µg/L and values range from 25.8 to 38.7 µg/L. Results show that most increases in [SO4] from the baseline occurred in areas with intensive coal mining activities, confirming previous studies. Sulfate inputs from acid rain were also documented. Slight increases in [Ba] since 2007 and higher [Ba] in areas with higher densities of gas wells when compared to other areas could document impacts from shale gas development, the prevalence of basin brines, or decreases in acid rain and its coupled effects on [Ba] related to barite solubility. The largest impacts on PA stream [Ba] and [SO4] are related to releases from coal mining or burning rather than oil and gas development.
AB - To understand how extraction of different energy sources impacts water resources requires assessment of how water chemistry has changed in comparison with the background values of pristine streams. With such understanding, we can develop better water quality standards and ecological interpretations. However, determination of pristine background chemistry is difficult in areas with heavy human impact. To learn to do this, we compiled a master dataset of sulfate and barium concentrations ([SO4], [Ba]) in Pennsylvania (PA, USA) streams from publically available sources. These elements were chosen because they can represent contamination related to oil/gas and coal, respectively. We applied changepoint analysis (i.e., likelihood ratio test) to identify pristine streams, which we defined as streams with a low variability in concentrations as measured over years. From these pristine streams, we estimated the baseline concentrations for major bedrock types in PA. Overall, we found that 48,471 data values are available for [SO4] from 1904 to 2014 and 3243 data for [Ba] from 1963 to 2014. Statewide [SO4] baseline was estimated to be 15.8 ± 9.6 mg/L, but values range from 12.4 to 26.7 mg/L for different bedrock types. The statewide [Ba] baseline is 27.7 ± 10.6 µg/L and values range from 25.8 to 38.7 µg/L. Results show that most increases in [SO4] from the baseline occurred in areas with intensive coal mining activities, confirming previous studies. Sulfate inputs from acid rain were also documented. Slight increases in [Ba] since 2007 and higher [Ba] in areas with higher densities of gas wells when compared to other areas could document impacts from shale gas development, the prevalence of basin brines, or decreases in acid rain and its coupled effects on [Ba] related to barite solubility. The largest impacts on PA stream [Ba] and [SO4] are related to releases from coal mining or burning rather than oil and gas development.
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U2 - 10.1007/s10653-017-0031-6
DO - 10.1007/s10653-017-0031-6
M3 - Article
C2 - 29027593
AN - SCOPUS:85031415820
VL - 40
SP - 865
EP - 885
JO - Environmental Geochemistry and Health
JF - Environmental Geochemistry and Health
SN - 0269-4042
IS - 2
ER -