The fracking debate reached its zenith a few years ago, with the industry largely winning the war over environmentalists. Since then, tens of thousands of wells have been drilled across the country. But the debate is not entirely dead—and even some oil companies are a little uneasy with the pace of drilling underway in certain parts of the country. In Oklahoma—hardly a haven for hippy environmentalists—there’s some anxiety that the oil industry is drilling too much and too aggressively, and not just because of the spike in seismic activity that the state has seen in recent years. The concern is over groundwater, the same issue that has characterized the fracking debate for much of the last decade. However, what makes Oklahoma interesting is that it isn’t just environmentalists raising questions about fracking. Some oil producers also warn that the shale industry’s slapdash approach to drilling is endangering groundwater resources. […]