dc.contributor.author |
Osborn, Stephen G |
|
dc.contributor.author |
Vengosh, Avner |
|
dc.contributor.author |
Warner, Nathaniel R |
|
dc.contributor.author |
Jackson, Robert B |
|
dc.date.accessioned |
2011-07-15T18:45:06Z |
|
dc.date.available |
2011-07-15T18:45:06Z |
|
dc.date.issued |
2011-05-09 |
|
dc.identifier.uri |
https://hdl.handle.net/10161/4642 |
|
dc.description.abstract |
Directional drilling and hydraulic-fracturing technologies are dramatically increasing
natural-gas extraction. In aquifers overlying the Marcellus and Utica shale formations
of northeastern Pennsylvania and upstate New York, we document systematic evidence
for methane contamination of drinking water associated with shale gas extraction.
In active gas-extraction areas (one or more gas wells within 1 km), average and maximummethane
concentrations in drinking-water wells increased with proximity to the nearest gas
well and were 19.2 and 64 mg CH4 L−1 (n ¼ 26), a potential explosion hazard; in contrast,
dissolved methane samples in neighboring nonextraction sites (no gas wells within
1 km) within similar geologic formations and hydrogeologic regimes averaged only 1.1
mgL−1 (P < 0.05; n ¼ 34). Average δ13C-CH4 values of dissolved methane in shallow
groundwater were significantly less negative for active than for nonactive sites (−37
7‰ and −54 11‰, respectively; P < 0.0001). These δ13C-CH4 data, coupled with the
ratios of methane-to-higher-chain hydrocarbons, and δ2H-CH4 values, are consistent
with deeper thermogenic methane sources such as the Marcellus and Utica shales at
the active sites and matched gas geochemistry from gas wells nearby. In contrast,
lower-concentration samples from shallow groundwater at nonactive sites had isotopic
signatures reflecting a more biogenic or mixed biogenic/thermogenic methane source.
We found no evidence for contamination of drinking-water samples with deep saline
brines or fracturing fluids. We conclude that greater stewardship, data, and—possibly—regulation
are needed to ensure the sustainable future of shale-gas extraction and to improve
public confidence in its use.
|
|
dc.description.sponsorship |
We gratefully acknowledge financial support from Fred and Alice Stanback to the Nicholas
School of the Environment and from the Duke Center on Global Change.
|
|
dc.language.iso |
en_US |
|
dc.publisher |
Proceedings of the National Academy of Sciences |
|
dc.relation.isversionof |
10.1073/pnas.1100682108 |
|
dc.title |
Methane contamination of drinking water accompanying gas-well drilling and hydraulic
fracturing
|
|
dc.type |
Journal article |
|
duke.contributor.id |
Vengosh, Avner|0334554 |
|
duke.contributor.id |
Jackson, Robert B|0217454 |
|
duke.contributor.orcid |
Vengosh, Avner|0000-0001-8928-0157 |
|