Yet droughts plagued the region, making agriculture difficult. Tapping into Wyoming's resource wealth, the Christensens staked claims on the property, selling mining and drilling rights to companies that helped transform the Powder River Basin into the energy basket of America.
Uranium was discovered underneath Christensen Ranch in 1973. In 1978, after the property had been divided between cousins, Westinghouse Electric launched the first large-scale uranium mine on John Christensen's portion.
Modern mining for the radioactive ore inevitably pollutes water.
To avoid digging big holes in the ground, operators inject a mixture of sodium bicarbonate, hydrogen peroxide and oxygen into the rock to separate out the minerals and bond to the uranium. Then, they vacuum out the uranium-laden fluids to make a fine powder called yellowcake. The process leaves a toxic mix of heavy metals and radioactive ions floating in the groundwater and generates millions of gallons of waste that need to be dumped deeper underground.
The federal Safe Drinking Water Act, implemented in the early 1980s as mining began in earnest on Christensen Ranch, posed a potential hurdle to such ventures because it prohibited disposal of waste in aquifers. But the law allowed regulators to exempt aquifers if they determined that water was too dirty to use, or buried too deep to be worth pumping to the surface, or unlikely to be needed.
In 1982, when Wyoming officials anticipated the need for an aquifer exemption at Christensen Ranch, the state's then-governor, Ed Herschler, wrote to urge EPA officials to streamline their review of such requests and not to delay energy projects or interfere with Wyoming regulators. Steven Durham, the EPA's regional administrator at the time, wrote back to assure the governor the EPA would not second guess state officials, and that he had adjusted the rules so that they "should assure a speedy finalization of any exemptions."