| Title | Shale gas development impacts on surface water quality in Pennsylvania |
| Publication Type | Journal Article |
| Authors | Olmstead, Sheila M., Lucija A. Muehlenbachs, Jhih-Shyang Shih, Ziyan Chu, and Alan J. Krupnick |
| Journal | Proceedings of the National Academy of Sciences |
| ISSN | 0027-8424, 1091-6490 |
| Abstract | Concern has been raised in the scientific literature about the environmental implications of extracting natural gas from deep shale formations, and published studies suggest that shale gas development may affect local groundwater quality. The potential for surface water quality degradation has been discussed in prior work, although no empirical analysis of this issue has been published. The potential for large-scale surface water quality degradation has affected regulatory approaches to shale gas development in some US states, despite the dearth of evidence. This paper conducts a large-scale examination of the extent to which shale gas development activities affect surface water quality. Focusing on the Marcellus Shale in Pennsylvania, we estimate the effect of shale gas wells and the release of treated shale gas waste by permitted treatment facilities on observed downstream concentrations of chloride (Cl−) and total suspended solids (TSS), controlling for other factors. Results suggest that (i) the treatment of shale gas waste by treatment plants in a watershed raises downstream Cl− concentrations but not TSS concentrations, and (ii) the presence of shale gas wells in a watershed raises downstream TSS concentrations but not Cl− concentrations. These results can inform future voluntary measures taken by shale gas operators and policy approaches taken by regulators to protect surface water quality as the scale of this economically important activity increases. |
| Notes | 'Summary InformationWhat it is: study on the impacts of shale gas development on water quality.Conclusions of article: treatment plants reduce chloride concentrations but not TSS concentrations.\n - mcdevl2'
'\nStudy on how much \"shale gas development activities\" affect surface water. \nData is from real-life data and models.\n\"Results for Cl− suggest that the presence of shale gas wells upstream in a monitor’s watershed does not raise observed concentrations but that the treatment and release of wastewater from shale gas wells by permitted facilities upstream in a monitor’s watershed does. These results are not consistent with the presence of significant flows of high-Cl− shale gas waste through accidental releases directly into surface water from well sites. However, surface water disposal of treated waste from shale gas wells represents a potentially important water quality burden. Taking into account average watershed size and mean Cl− concentrations, the coefficients in Table 1 suggest that a 1-SD increase in the spatial density of upstream waste treatment facilities (an additional 1.5 facilities treating waste upstream in a watershed) results in a 10–11% increase in Cl− downstream, depending on the specification.\" (5)\n\n - mcdevl2'
|
| URL | http://www.pnas.org/content/early/2013/03/06/1213871110 |
| DOI | 10.1073/pnas.1213871110 |
Zotero attachments as links:
