@article {26382,
	title = {Lepidolite extraction solid by-product: Mitigation of thallium leaching and utilization of radiogenic strontium isotopes as a tracer},
	journal = {Environmental Advances},
	volume = {3},
	year = {2021},
	pages = {100035},
	abstract = {The emerging growth of lithium-ion battery usage necessitates the development of unconventional resources for battery grade lithium carbonate. Extraction of lithium from micas such as lepidolite produces several marketable by-products as well as a silt-sized gypsum rich blended residue containing elevated level of thallium (Tl). The goal of this study was to assess the alternative use of the blended residue as fill material for mine reclamation. Bulk elemental analysis and shake flask extraction of the blended residue showed that radionuclide and heavy metal levels of the solid blended residue and its leachate were within the guidelines for soil and its leachates. However, Tl concentration (24.7 {\textpm} 0.9 mg/kg), possibly in the forms of water-soluble salts in the blended residue, was much higher than the general level of Tl in naturally uncontaminated soil (\&lt;1 mg/kg). Thus, the efficiency of four easily accessible amendments (peat, clay, biochar, and topsoil) in mitigating the release of Tl was evaluated using a modified SPLP procedure. In addition, the usefulness of radiogenic Sr isotopes (87Sr/86Sr) as a tracer of the leachate plumes derived from the blended residue was assessed. Results from SPLP experiments showed that Tl was released from the blended residue under a wide range of pH values, especially under acidic conditions. Mixing proportions of the blended residue and amendment (1:9 or 1:1) did not appreciably affect the high Tl removal efficiencies (68 {\textendash} 89\%) of clay, biochar, and topsoil. While mixing time did not affect the Tl removal efficiencies of clay and topsoil, Tl removal efficiency of biochar proportionally increased with mixing time and was at the highest value (~95\%) among four amendments, if the mixing time was at least 7 days. Peat was not an effective amendment because its acidity possibly enhanced the release of Tl. The\&nbsp;87Sr/86Sr ratios in leachates of the blended residue (0.792 {\textendash} 0.810) and its amendment mixtures were significantly higher than those in surface and groundwaters, soil leachates, and coal mine drainage. Thus, when the blended residue is used as fill material for mine reclamation,\&nbsp;87Sr/86Sr can be a powerful naturally occurring tracer in distinguishing Tl from the blended residue from other major sources of Tl in the environment. Overall, this study recommends clay and soils as the most promising amendments in mitigating the release of Tl in well-drained systems, and biochar for poor drainage conditions.},
	url = {https://doi.org/10.1016/j.envadv.2021.100035},
	author = {Thai T Phan and Leah Fulton and John Ulkem and Steve Aiken and Amber Blackwell and Joe Walsh and Peter Walker and Fereidoun Rezanezhad}
}
@article {26381,
	title = {Tracking natural CO2 migration through a sandstone aquifer using Sr, U and C isotopes: Chimay{\'o}, New Mexico, USA},
	journal = {International Journal of Greenhouse Gas Control},
	volume = {104},
	year = {2021},
	pages = {103209},
	abstract = {
	The geochemical and isotopic characteristics of groundwaters in Chimay{\'o}, New Mexico, reflect processes that affect water quality in the Tesuque Aquifer, which overlies a leaking natural CO2\&nbsp;source in a structurally complex region. In this study, select isotopes (δ13C,\&nbsp;87Sr/86Sr,\&nbsp;234U/238U) are applied to groundwaters to better understand CO2\&nbsp;transport mechanisms and related water-rock interactions that impact Chimay{\'o} groundwater. Carbon stable isotope ratios of dissolved inorganic carbon (DIC; δ13CDIC\&nbsp;= -15.10{\textperthousand} to 4.50{\textperthousand}) identify a distinct source of upward-migrating CO2\&nbsp;that interacts with the groundwater. Groundwater\&nbsp;87Sr/86Sr compositions (0.7098 to 0.7154) reflect intrusion of varying amounts of saline water associated with the high CO2\&nbsp;source, while\&nbsp;234U/238U ratios corroborate presence of deep groundwater and suggest impacts from distinctive natural uranium sources are affecting groundwater. Previous work proposed two CO2\&nbsp;transport mechanisms at the site: (1) dissolved in deep brine that underlies the aquifer and (2) in the gas phase; this study uses isotope mixing models to identify wells that are affected by these CO2\&nbsp;transport mechanisms and demonstrates that both transport mechanisms are associated with impaired groundwaters. Overall, this study demonstrates that applying multiple isotope systems (δ13CDIC,\&nbsp;87Sr/86Sr,\&nbsp;234U/238U) is a dynamic tool for identifying and measuring the impact of CO2\&nbsp;leakage from a sequestration site.




},
	url = {https://doi.org/10.1016/j.ijggc.2020.103209},
	author = {JB Gardiner and RC Capo and DL Newell and BW Stewart and TT Phan and EH Keating and GD Guthrie and JA Hakala}
}
@article {24270,
	title = {Application of isotopic and geochemical signals in unconventional oil and gas reservoir produced waters toward characterizing in situ geochemical fluid-shale reactions},
	journal = {Science of the Total Environment},
	volume = {714},
	year = {2020},
	url = {https://www.sciencedirect.com/science/article/pii/S0048969720303776},
	author = {Thai T Phan and J Alexandra Hakala and Shikha Sharma}
}
@article {16109,
	title = {Barium Isotopes Track the Source of Dissolved Solids inUnconventional Shale Gas Produced Water},
	journal = {Environmental Science and Technology},
	volume = {54},
	number = {7},
	year = {2020},
	pages = {4275{\textendash}4285},
	url = {https://pubs.acs.org/doi/abs/10.1021/acs.est.0c00102},
	author = {Zachary G. Tieman and Brian W. Stewart and Rosemary C. Capo and Thai T. Phan and Christina L. Lopano and J. Alexandra Hakala}
}
@article {16110,
	title = {Neodymium isotopes track sources of rare earth elements in acidic mine waters},
	journal = {Geochimica et Cosmochimica Acta},
	volume = {269},
	year = {2020},
	pages = {465-483},
	url = {https://www.sciencedirect.com/science/article/abs/pii/S0016703719306982},
	author = {Irene L. R. Wallrich and Brian W. Stewart and Rosemary C. Capo and Benjamin C. Hedin and Thai T. Phan}
}
@article {26380,
	title = {Utilization of produced water baseline as a groundwater monitoring tool at a CO2-EOR site in the Permian Basin, Texas, USA},
	journal = {Applied Geochemistry},
	volume = {121},
	year = {2020},
	pages = {104688},
	abstract = {Carbon dioxide (CO2) enhanced oil recovery (EOR) provides a pathway for economic reuse and storage of CO2, a greenhouse gas. One challenge with this practice is ensuring CO2\&nbsp;injection does not result in target reservoir fluids migrating into overlying shallow (\&lt;1000\&nbsp;m) groundwater formations. Effective monitoring for leakage from storage formations could involve measuring sensitive chemical indicators in overlying groundwater units and within the producing formation itself for evidence of deviation from an initial state. In this study, produced waters and overlying groundwaters were monitored over a five-year period to evaluate which geochemical signals may be useful to ensure that oilfield produced waters did not impact overlying groundwaters. During this five-year period, a mature carbonate oil reservoir in the Permian Basin transitioned from a waterflooding operation to a water-alternating-gas injection (WAG), in which the formation was flooded with CO2\&nbsp;and various mixtures of produced water. Significant increases in dissolved inorganic constituents [alkalinity, TDS, Na+, Cl-, SO42-] were observed in produced waters following CO2\&nbsp;injection; however, carbonate reservoir dissolution-precipitation reactions appear to be minimal and injected CO2\&nbsp;appears to be stored via solubility trapping. Although there are statistically significant geochemical variations following CO2\&nbsp;injection, applying isometric log-ratios to certain parameters establishes a narrow range for post-CO2\&nbsp;injection produced waters. This narrow range can be considered a baseline for post-CO2\&nbsp;injection produced waters; this baseline can be utilized to monitor overlying local groundwaters for produced water intrusion. Additionally, certain parameters [Na+, Ca2+, K+, Cl-, alkalinity, and TDS] display large concentration disparities between produced water and overlying groundwaters; these parameters would be sensitive indicators of produced water intrusion into overlying groundwaters.},
	url = {https://doi.org/10.1016/j.apgeochem.2020.104688},
	author = {James Gardiner and R Burt Thomas and Thai T Phan and Mengling Stuckman and Jiaan Wang and Mitchell Small and Christina Lopano and J Alexandra Hakala}
}
@article {14889,
	title = {Rare earth elements and radiogenic strontium isotopes in carbonate minerals reveal diagenetic influence in shales and limestones in the Appalachian Basin},
	journal = {Chemical Geology},
	year = {2019},
	url = {https://doi.org/10.1016/j.chemgeo.2019.01.018},
	author = {Phan, T.T. and Hakala, A.J. and Lopano, C.L. and Sharma, S.}
}
@article {14890,
	title = {Variations in uranium concentrations and uranium isotope signatures in the sediments of two lakes near Bancroft, Ontario, Canada},
	journal = {Chemical Geology},
	year = {2019},
	author = {Wang, W. and Dang, D.H. and Novotnik, B. and Phan, T.T. and Evans, R.D.}
}
@article {14880,
	title = {Geochemical and multi-isotopic (87Sr/86Sr, 143Nd/144Nd, 238U/235U) perspectives of sediment sources, depositional conditions, and diagenesis of the Marcellus Shale, Appalachian Basin, USA},
	journal = {Geochimica et Cosmochimica Acta},
	volume = {222},
	year = {2018},
	pages = {187-211},
	url = {http://www.sciencedirect.com/science/article/pii/S0016703717306841},
	author = {Phan, Thai T. and Gardiner, J.B. and Capo, R.C. and Stewart, B.W.}
}
@article {14881,
	title = {Influence of colloids on metal concentrations and radiogenic strontium isotopes in groundwater and oil and gas-produced waters},
	journal = {Applied Geochemistry},
	volume = {95},
	year = {2018},
	pages = {85-96},
	url = {http://www.sciencedirect.com/science/article/pii/S0883292718301343},
	author = {Thai T. Phan and J. Alexandra Hakala and Daniel J. Bain}
}
@article {14879,
	title = {Role of water\&minus;rock interaction in the geochemical evolution of Marcellus Shale produced waters},
	journal = {International Journal of Coal Geology},
	number = {191},
	year = {2018},
	pages = {95-111},
	url = {https://www.sciencedirect.com/science/article/pii/S0166516217306638},
	author = {Thai T. Phan and Amelia N. Paukert Vankeuren and J. Alexandra Hakala}
}
@article {14882,
	title = {Geochemical and lithium isotope tracking of dissolved solid sources in Permian Basin carbonate reservoir and overlying aquifer waters at an enhanced oil recovery site, northwest Texas, USA},
	journal = {Applied Geochemistry},
	volume = {87},
	year = {2017},
	pages = {122-135},
	url = {http://www.sciencedirect.com/science/article/pii/S0883292717303177},
	author = {Pfister, S. and Capo, R.C. and Stewart, B.W. and Macpherson, G.L. and Phan, T.T. and Gardiner, J.B. and Diehl, J.R. and Lopano, C. and Hakala, J.A.}
}
@article {14883,
	title = {Factors controlling Li concentration and isotopic composition in formation waters and host rocks of Marcellus Shale, Appalachian Basin},
	journal = {Chemical Geology},
	volume = {420},
	year = {2016},
	pages = {162-179},
	url = {http://www.sciencedirect.com/science/article/pii/S0009254115300954},
	author = {Phan, T.T. and Capo, R.C. and Stewart, B.W. and Macpherson, G.L. and Rowan, E.L and Hammack, R. W.}
}
@article {14884,
	title = {Direct determination (without chromatographic separation) of lithium isotopes in saline fluids using MC-ICP-MS: establishing limits on water chemistry},
	journal = {J. Anal. At. Spectrom.},
	volume = {30},
	year = {2015},
	pages = {1673-1678},
	url = {http://dx.doi.org/10.1039/C5JA00060B},
	author = {Macpherson, G.L. and Phan, T.T. and Stewart, B.W.}
}
@article {14885,
	title = {Trace metal distribution and mobility in drill cuttings and produced waters from Marcellus Shale gas extraction: Uranium, arsenic, barium},
	journal = {Applied Geochemistry},
	volume = {60},
	year = {2015},
	pages = {89{\textendash}103},
	url = {https://www.sciencedirect.com/science/article/pii/S0883292715000207?via\%3Dihub},
	author = {Phan, T.T. and Capo, R.C. and Stewart, B.W. and Graney, J.R. and Johnson, J.D. and Sharma, S. and Toro, J.}
}
@article {14886,
	title = {Temperature-dependent Li isotope ratios in Appalachian Plateau and Gulf Coast Sedimentary Basin saline water},
	journal = {Geofluids},
	volume = {14},
	year = {2014},
	pages = {419{\textendash}429},
	url = {https://onlinelibrary.wiley.com/doi/full/10.1111/gfl.12084},
	author = {Macpherson, G.L. and Capo, R.C. and Stewart, B.W. and Phan, T.T. and Schroeder, K. and Hammack, R.W.}
}
@article {14887,
	title = {High throughput method for Sr extraction from variable matrix waters and 87Sr/86Sr isotope analysis by MC-ICP-MS},
	journal = {Journal of Analytical Atomic Spectrometry},
	volume = {28},
	year = {2013},
	pages = {1338{\textendash}1344},
	url = {https://pubs.rsc.org/en/content/articlelanding/2013/ja/c3ja30350k$\#$!divAbstract},
	author = {Wall, A.J. and Capo, R.C. and Stewart, B.W. and Phan, T.T. and Jain, J.C. and Hakala, J.A. and Guthrie, G.D.}
}
@article {14888,
	title = {Pilot scale investigation of zinc and sulphate removal from industrial discharges by biological sulphate reduction with molasses as electron donor},
	journal = {Environmental Technology},
	volume = {30},
	year = {2009},
	pages = {1229-1239},
	url = {https://www.tandfonline.com/doi/abs/10.1080/09593330903233901},
	author = {Liamleam, W. and Oo, Z.K. and Thai, P.T. and Annachhatre, A.P.}
}
