Groundwater of the Rosita uranium deposit (baseline and monitoring wells)
South Texas, Coastal Plain (Duval County), United States
Groundwater
- Type
- Groundwater
Roll-front deposit in Miocene fluvial sandstones of the Goliad Formation (Texas Coastal Plain), uranium leached from Catahoula Formation tuffs; mined by in situ recovery (ISR) with oxygen by Uranium Resources Inc. Areas RPA1 to RPA3 mined from 1990 to 1999 (then 2008 and 2012 for RPA3) and restored by reverse osmosis from 2001 to 2007, RPA4 not mined; sampled in 2011. Across the eight transects, (234U/238U) decreases towards the ore from both oxidising and reducing sides, a sign of an active front and recent U mobility; δ238U decreases towards the reducing zone (down to -3.96), explained by Rayleigh deposition from an increasingly light dissolved U reservoir, with several deposition and dissolution cycles (Placzek et al., 2016). Coordinates not published (map only).
δ238U in ‰ (per mil) Values of the same system
Standard : 238U/235U = 137,794 (Goldmann et al., 2015)
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 0.01 ± 0.24 ‰ | 1 | water of well BL7 (area RPA1, ore zone, ore extracted, restoration completed) Single analysis; ± 0.24 ‰ (2σ); 1009 µg/L U; about -0.3 ‰ relative to CRM 112-A. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.09 ± 0.18 ‰ | 1 | water of well BL10 (area RPA2b, ore zone, ore extracted, restoration completed) Single analysis; ± 0.18 ‰ (2σ); 333 µg/L U; about -0.22 ‰ relative to CRM 112-A. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.34 ± 0.24 ‰ | 1 | water of well BL22 (area RPA2a, ore zone, ore extracted, restoration completed) Single analysis; ± 0.24 ‰ (2σ); 2602 µg/L U; about 0.03 ‰ relative to CRM 112-A. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −0.03 ± 0.22 ‰ | 1 | water of well BL28 (area RPA3, ore zone, ore extracted, restoration not yet undertaken) Single analysis; ± 0.22 ‰ (2σ); 6462 µg/L U; about -0.34 ‰ relative to CRM 112-A; fraction of U deposited estimated at 25 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.36 ± 0.23 ‰ | 1 | water of well BL29 (area RPA3, ore zone, ore extracted, restoration completed) Single analysis; ± 0.23 ‰ (2σ); 10,194 µg/L U; about 0.05 ‰ relative to CRM 112-A. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −0.54 ± 0.22 ‰ | 1 | water of well BL36 (area RPA4, ore zone, no extraction undertaken) Single analysis; ± 0.22 ‰ (2σ); 22 µg/L U; about -0.85 ‰ relative to CRM 112-A; fraction of U deposited estimated at over 99.9 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.53 ± 0.23 ‰ | 1 | water of well MW25 (area RPA1, oxidising zone, monitoring well) Single analysis; ± 0.23 ‰ (2σ); 671 µg/L U; about 0.22 ‰ relative to CRM 112-A. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −1.73 ± 0.2 ‰ | 1 | water of well MW34 (area RPA1, reducing zone, monitoring well) Single analysis; ± 0.2 ‰ (2σ); 32 µg/L U; about -2.04 ‰ relative to CRM 112-A; fraction of U deposited estimated at over 99.9 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −0.05 ± 0.21 ‰ | 1 | water of well MW45 (area RPA2a, oxidising zone, monitoring well) Single analysis; ± 0.21 ‰ (2σ); 97 µg/L U; about -0.36 ‰ relative to CRM 112-A; fraction of U deposited estimated at 39 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.07 ± 0.32 ‰ | 1 | water of well MW66 (area RPA2b, oxidising zone, monitoring well) Single analysis; ± 0.32 ‰ (2σ); 103 µg/L U; about -0.24 ‰ relative to CRM 112-A. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −1.47 ± 0.2 ‰ | 1 | water of well MW75 (area RPA3, reducing zone, monitoring well) Single analysis; ± 0.2 ‰ (2σ); 22 µg/L U; about -1.78 ‰ relative to CRM 112-A; fraction of U deposited estimated at over 99.9 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −1.26 ± 0.25 ‰ | 1 | water of well MW85 (area RPA2a, reducing zone, monitoring well) Single analysis; ± 0.25 ‰ (2σ); 27 µg/L U; about -1.57 ‰ relative to CRM 112-A; fraction of U deposited estimated at over 99.9 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −1.21 ± 0.26 ‰ | 1 | water of well MW102 (reducing zone, monitoring well) Single analysis; ± 0.26 ‰ (2σ); 27 µg/L U; about -1.52 ‰ relative to CRM 112-A; fraction of U deposited estimated at over 99.9 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −0.34 ± 0.15 ‰ | 1 | water of well MW129 (area RPA3, oxidising zone, monitoring well) Single analysis; ± 0.15 ‰ (2σ); 39 µg/L U; about -0.65 ‰ relative to CRM 112-A; fraction of U deposited estimated at 97 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| −0.01 ± 0.26 ‰ | 1 | water of well MW160 (area RPA4, oxidising zone, monitoring well) Single analysis; ± 0.26 ‰ (2σ); 24 µg/L U; about -0.32 ‰ relative to CRM 112-A; fraction of U deposited estimated at 10 % (Rayleigh model, α = 0.99954 of Bopp et al., 2010). | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… |
(234U/238U) isotope ratio, no unit Values of the same system
Standard : équilibre séculaire
| Value | Range | n | Mineral or matrix | Source |
|---|---|---|---|---|
| 0.83 ± 0.01 | 1 | water of well BL7 (area RPA1, ore zone, ore extracted, restoration completed) Single analysis; ± 0.01 (2σ); 1009 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.85 ± 0.01 | 1 | water of well BL10 (area RPA2b, ore zone, ore extracted, restoration completed) Single analysis; ± 0.01 (2σ); 333 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.83 ± 0.01 | 1 | water of well BL22 (area RPA2a, ore zone, ore extracted, restoration completed) Single analysis; ± 0.01 (2σ); 2602 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.84 ± 0.02 | 1 | water of well BL28 (area RPA3, ore zone, ore extracted, restoration not yet undertaken) Single analysis; ± 0.02 (2σ); 6462 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.81 ± 0.02 | 1 | water of well BL29 (area RPA3, ore zone, ore extracted, restoration completed) Single analysis; ± 0.02 (2σ); 10,194 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.91 ± 0.02 | 1 | water of well BL36 (area RPA4, ore zone, no extraction undertaken) Single analysis; ± 0.02 (2σ); 22 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.8 ± 0.02 | 1 | water of well MW25 (area RPA1, oxidising zone, monitoring well) Single analysis; ± 0.02 (2σ); 671 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.99 ± 0.02 | 1 | water of well MW34 (area RPA1, reducing zone, monitoring well) Single analysis; ± 0.02 (2σ); 32 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 1.05 ± 0.02 | 1 | water of well MW45 (area RPA2a, oxidising zone, monitoring well) Single analysis; ± 0.02 (2σ); 97 µg/L U; 234U excess, typical of waters weathering the host rocks. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 1.01 ± 0.02 | 1 | water of well MW66 (area RPA2b, oxidising zone, monitoring well) Single analysis; ± 0.02 (2σ); 103 µg/L U; close to secular equilibrium. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 1.12 ± 0.02 | 1 | water of well MW75 (area RPA3, reducing zone, monitoring well) Single analysis; ± 0.02 (2σ); 22 µg/L U; 234U excess, typical of waters weathering the host rocks. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 0.98 ± 0.02 | 1 | water of well MW85 (area RPA2a, reducing zone, monitoring well) Single analysis; ± 0.02 (2σ); 27 µg/L U; a ratio below 1 reflects recent leaching of U from the ore itself. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 1.22 ± 0.02 | 1 | water of well MW102 (reducing zone, monitoring well) Single analysis; ± 0.02 (2σ); 27 µg/L U; 234U excess, typical of waters weathering the host rocks. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 1.28 ± 0.01 | 1 | water of well MW129 (area RPA3, oxidising zone, monitoring well) Single analysis; ± 0.01 (2σ); 39 µg/L U; 234U excess, typical of waters weathering the host rocks. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… | |
| 1.54 ± 0.02 | 1 | water of well MW160 (area RPA4, oxidising zone, monitoring well) Single analysis; ± 0.02 (2σ); 24 µg/L U; 234U excess, typical of waters weathering the host rocks. | Placzek et al. (2016), Uranium isotope composition of waters from South Texas uranium ore… |
Deposits of the same type
- Vinto drinking water (DW1 to DW3) Bolivia
- Coal-mine tip, site 1 (unconfined chalk aquifer) France
- Coal-mine tip, site 2 (confined chalk aquifer) France
- Pebble deposit seeps United States
- Yarlung Tsangpo basin geothermal springs China
- Archibarca alluvial fan groundwater Argentina
- Rosario River fan hot springs Argentina
- Jiangling Basin thermal waters (JS-W1, YC-W1) China
Cite this page
IsoFind Atlas (2026). Groundwater of the Rosita uranium deposit (baseline and monitoring wells), isotope signatures. https://www.isofind.tech/isotopes/en/sites/nappe-du-gisement-d-uranium-de-rosita-puits-de-controle-et-de-suivi/ (accessed 2026-10-16).
@misc{isofind2026groundwateroftherositauranium,
title = {Groundwater of the Rosita uranium deposit (baseline and monitoring wells), isotope signatures},
author = {{IsoFind Atlas}},
year = {2026},
url = {https://www.isofind.tech/isotopes/en/sites/nappe-du-gisement-d-uranium-de-rosita-puits-de-controle-et-de-suivi/},
note = {Accessed 2026-10-16}
}Updated : 2026-10-16