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Another potential threat to groundwater is mining activities. Under the Texas Surface Mining and Reclamation
Act and the Texas Uranium Surface Mining and Reclamation Act, the Railroad Commission of Texas is authorized to enforce state laws, including requiring groundwater monitoring for pre-mining,
mining and post-mining activities *. While there is currently no strip mining of uranium in Texas, there is still one site -- the Panna Maria project in Karnes County
-- that is still being restored following uranium strip-mining activity. This activity requires groundwater monitoring under Texas Railroad Commission guidelines. In addition, four tailings
and waste sites—where the uranium was milled and extracted from the ore—in Karnes and Live Oak counties have been closed and covered to prevent further contamination of subsurface
aquifers or radioactive waste emissions. The reclaimed sites have resulted in groundwater contamination, including one confirmed case at the Chevron Resources facility in 1996.* Studies by Texas A & M investigators have documented groundwater contamination by uranium mining as the cause of elevated arsenic and uranium concentrations in the Lake Corpus Christi/Choke Canyon Reservoir system. The remediation efforts by the Department of Energy in Falls City have not successfully cleaned up contamination there, and the groundwater must be continue to be monitored.
Texas is also the country's largest user of coal, and the fifth largest producer of coal, mining more than
53,000 short tons at 14 surface mines in 1999. More than 98 percent of the coal mined in Texas is used in electric power plants (* In 1997, were 11 companies mining 25 different sites, while two other sites had closed and were being cleaned up. By 2002, only seven companies were mining 13 permitted sites, with four other permittees cleaning up their sites, and two new permitted sites yet to commence mining operations *. While the Railroad Commission requires that
companies monitor groundwater quarterly for some basic parameters, such as fluoride, nitrates, and magnesium, companies are required to monitor for trace metals, such as lead, arsenic,
cadmium, mercury, and selenium, only once per year. Currently, about 420 wells are being sampled four times a year at mining or reclamation sites, and results do not indicate any
contamination problems. Instead, the major groundwater impact has been the drawdown of localized aquifers. Once the mined areas and localized aquifers are resaturated through precipitation,
adjacent aquifers and streamflows could be impacted by the mining activities, however.*
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Coal, Lignite and Uranium Surface Mines
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Source: Texas Mine Land Inventory
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