Report by hydrogeologist finds Texas in-situ uranium mines have been unable to restore ground water aquifers to premining water quality
State regulators routinely approve leaving higher uranium levels in ground water; author questions mine operators' scientific understanding of aquifers
Posted October 24, 2008, Updated March 30, 2009
Note: Upon the request of Dr. Darling, his report was removed from this website on March 28, 2009. Evidently, another hydrogeologist with close ties to uranium mining attempted to file an anonymous complaint with the Texas Board of Licensure for Professional Geoscientists that an unsigned/unsealed version of Dr. Darling's report had been publicly released. A signed and sealed version was posted below on March 30, 2009. As of this date, no one has published a rebuttal to Dr. Darling's report. JW
A groundbreaking report by hydrogeologist Bruce K. Darling, PhD, P.G. for the first time provides data from the Texas Commission on Environmental Quality (TCEQ) documenting the failure of Texas in-situ uranium mine operators to clean up ground water aquifers following mining. Darling concludes that Texas mining regulators have routinely granted requests for relaxed restoration standards at in-situ uranium mining sites and that no evidence has been found that Texas authorities have ever denied such a request.
He further claims that such relaxed restoration standards are an admission that the mine operators are unable to meet the original restoration standards and that "this calls into question the operators' understanding of the geochemistry of the hydrogeologic systems that they are exploiting."
The report was commissioned by Blackburn & Carter, a Houston law firm.
Dr. Darling is well-qualified to review these data, according to his bio published in the journal of the American Institute of Professional Geologists:
He has served as a hydrogeologist with the University of Texas Bureau of Economic Geology and Law Engineering and Environmental Services, and as a minerals economist with the US Bureau of Mines. Mr. Darling has extensive experience in water-resource development and management projects. He has completed site-characterization studies of low-level radioactive waste disposal facilities in Texas and North Carolina. His background encompasses supervising geological field reconnaissance, development of geochemical and analytic transport models, groundwater exploration and development programs, exploration geology, and mineral resource economics. Mr. Darling holds a Ph.D. degree in hydrology and an MA degree in mineral economics from the University of Texas at Austin. He also earned an MS in geology and a BA in philosophy from the University of Southwestern Louisiana. He is a member of the American Institute of Professional Geologists, the Association of Groundwater Scientists and Engineers, the Austin Geological Society, and the West Texas Geological Society. He is a licensed professional geologist in six states.
Darling used internal paper documents and spreadsheets from the Underground Injection Control office of the TCEQ to prepare the report. The original source documents are on microfiche and microfilm records located in the Central Records office of the TCEQ. Darling's work was hampered because TCEQ staff were reluctant to certify their own paper and digital documents as official records, and Darling found the microfiche and microfilm records to be poorly organized and difficult to search.
Darling found 27 permitted in-situ uranium mines in south Texas, including roughly 80 authorized production areas. Mine operations date from the 1980s through the present day.
Under Texas law, ground water restoration standards for 26 water quality indicators are established when production areas are permitted. Following mining, if the operator is unable to clean up the water to the original restoration standards, the operator may request that the standards be amended. Darling found 51 production areas where such ground water restoration amendments had been approved. With respect to uranium, mine operators were granted permission to leave higher levels of the radioactive metal in 43 different production areas.
In one area (Zamzow PAA-1) the acceptable level of uranium in the ground water was increased by an astounding 29,900%. The original restoration standard was 0.01 mg/l; the amended standard was 3.0 mg/l. For comparison, the federal maximum contaminant level (MCL) for uranium in drinking water is 0.03 mg/l. Zamzow is one of five ISL mines cited by Powertech as evidence that aquifers can be cleaned up after ISL mining. From Powertech's web page titled "Groundwater Protection":
The groundwater restoration, or cleanup of an aquifer impacted by in-situ uranium solution mining has been shown to be technically, physically and economically achievable. (Ref. NRC NUREG/CR 6870) Some recent successful ISR mine closures include the O'Hern, Hobson, Zamzow, Pawlik, and Longoria mines in South Texas, all owned by different companies. There are no historical cases in the United States where ISR has made a long-term negative impact on public health or the environment.
TCEQ data paint a different picture. For all five mines, uranium restoration values were amended in response to requests by the mines' operators. Amended restoration values were increased from 291% (O'Hern PAA-4) to 29,900% (Zamzow PAA-1). Although "last sample values" for uranium are not available for all five mines, three production areas showed significant increases in uranium levels after restoration efforts ceased: 213% for O'Hern PAA-4, 4,765% for Longoria PAA-2, and 10,538% for Longoria PAA-1.
Using Powertech's logic, an aquifer is successfully cleaned up even if the level of uranium in the ground water is 29,900% higher than the premining water quality, as long as a government agency approves the change. And this enormous increase in uranium contamination does not constitute "a long-term negative impact on public health or the environment."
The table below was compiled from data contained in Dr. Darling's report. Mine production areas in red are those cited by Powertech as examples of mines that have been successfully cleaned up.
JW
| Restoration History of Texas In-Situ Uranium Mines | |||||||
| Original | Amended | Last | |||||
| Uranium | Uranium | Uranium | |||||
| Production | Restoration | Restoration | Sample | ||||
| Mine | Area (PAA) | Value (mg/l) | Value (mg/l) | % Change | Value (mg/l) | % Change | |
| Benavides | 1 | 0.083 | 2.000 | 2310% | 1.040 | 1153% | |
| Benavides | 2 | 0.078 | 2.000 | 2464% | 0.279 | 258% | |
| Benavides | 3 | 0.120 | 3.000 | 2400% | 1.500 | 1150% | |
| Benavides | 4 | 2.000 | 0.950 | -53% | |||
| Brelum | 1 | 0.037 | 2.000 | 5305% | 0.025 | -32% | |
| Brelum | 2 | 0.031 | 2.000 | 6394% | 0.013 | -58% | |
| Bruni | 1 | 0.461 | 5.000 | 985% | 1.185 | 157% | |
| Bruni | 5-2 | 0.461 | 4.000 | 768% | 3.020 | 555% | |
| Burns/Moser | 2 | 0.050 | 1.700 | 3300% | no data | no data | |
| Burns/Moser | 3 | 0.082 | 1.250 | 1424% | no data | no data | |
| Burns/Moser | 4 | 0.020 | 0.200 | 900% | no data | no data | |
| Clay West | 1 | 0.400 | 0.800 | 100% | no data | no data | |
| El Mesquite | 2 | 0.085 | 1.350 | 1488% | no data | no data | |
| El Mesquite | 3 | 0.840 | 2.700 | 221% | 2.530 | 201% | |
| El Mesquite | 4 | 0.062 | 1.950 | 3045% | no data | no data | |
| Hobson | 1 | 0.025 | 0.290 | 1060% | no data | no data | |
| Holiday | 2 | 0.200 | 0.500 | 150% | no data | no data | |
| Holiday | 3 | 1.600 | 2.000 | 25% | no data | no data | |
| Holiday | 4 | 0.036 | 2.550 | 6983% | no data | no data | |
| Holiday | 5 | 0.063 | 1.095 | 1638% | no data | no data | |
| Holiday | 6 | 0.368 | 2.300 | 525% | no data | no data | |
| Lamprecht | 1 | 0.160 | 0.757 | 373% | no data | no data | |
| Las Palmas | 1 | 2.913 | 7.000 | 140% | no data | no data | |
| Las Palmas | 2 | 0.566 | 2.000 | 253% | no data | no data | |
| Las Palmas | 3 | 2.400 | 5.000 | 108% | no data | no data | |
| Longoria | 1 | 0.047 | 2.000 | 4155% | 5.000 | 10538% | |
| Longoria | 2 | 0.037 | 3.000 | 8008% | 1.800 | 4765% | |
| McBryde | 1 | 0.831 | 4.000 | 381% | no data | no data | |
| Mt Lucas | 1 | 0.293 | 0.550 | 88% | no data | no data | |
| Mt Lucas | 2 | 0.076 | 0.500 | 558% | no data | no data | |
| Mt Lucas | 3 | 0.770 | 1.750 | 127% | no data | no data | |
| Mt Lucas | 4 | 0.097 | 1.600 | 1549% | no data | no data | |
| Mt Lucas | 5 | 0.258 | 1.500 | 481% | no data | no data | |
| Mt Lucas | 6 | 0.125 | 2.000 | 1500% | no data | no data | |
| Mt Lucas | 7 | 0.047 | 1.000 | 2028% | no data | no data | |
| Mt Lucas | 8 | 0.334 | 1.250 | 274% | no data | no data | |
| Nell | 1 | 0.041 | 2.000 | 4778% | no data | no data | |
| O'Hern | 1 | 0.280 | 1.550 | 454% | no data | no data | |
| O'Hern | 4 | 0.307 | 1.200 | 291% | 0.960 | 213% | |
| Pawlik | 1A | 0.002 | 0.020 | 900% | no data | no data | |
| Rosita | 1 | 2.000 | 4.000 | 100% | 0.672 | -66% | |
| Tex-1 | 1 | 0.050 | 1.000 | 1900% | no data | no data | |
| Trevino | 1 | 0.015 | 2.000 | 13233% | no data | no data | |
| Trevino | 2a | 0.036 | 2.000 | 5456% | no data | no data | |
| West Cole | 1 | 0.169 | 2.750 | 1527% | no data | no data | |
| West Cole | 2 | 0.662 | 2.500 | 278% | no data | no data | |
| West Cole | 3 | 1.660 | 3.150 | 90% | no data | no data | |
| Zamzow | 1 | 0.010 | 3.000 | 29900% | no data | no data | |
| Notes: | |||||||
| 1. Only mine production areas with original uranium restoration values and amended values and/or | |||||||
| last sample values are included. | |||||||
| 2. Data are from the Texas Commission on Environmental Quality. | |||||||
| 3. The federal maximum contaminant level for uranium in drinking water is 0.03 milligrams per liter (mg/l). | |||||||
Report on Findings Related to the Restoration of In-Situ Uranium Mines in South Texas - Bruce K. Darling, Ph.D., P.G. - SOUTHWEST GROUNDWATER CONSULTING, LLC - September 29, 2008 (PDF 982 KB) Note: This is the "official" signed and sealed version.
Resume - Bruce K. Darling (PDF 88KB)
Consideration of Geochemical Issues in Groundwater Restoration at Uranium In-Situ Leach Mining Facilities (NUREG/CR-6870)
U.S. Nuclear Regulatory Commission and U.S. Geological Survey - January 2007 (PDF 2.0MB)