Mountain West (CO ID MT NV UT WY)

A rare chance for people to walk through the mile-long tunnel that gives entrance to Zion National Park was part of the park's centennial celebration.

"Federal environment officials investigating drinking water contamination near the ranching town of Pavillion, Wyo., have found that at least three water wells contain a chemical used in the natural gas drilling process of hydraulic fracturing."

"Researchers found that two of the Tetons' biggest glaciers have lost more than 20 percent of their surface area since the late 1960s."

Some residents are worried about a rural Nevada dump where decades of toxic refuse lie buried in shallow trenches.

In the Yaak Valley of Montana, environmentalists have been talking to loggers, snowmobilers and other longtime opponents of wilderness protection about the future of public lands. Rick Bass writes of his involvement in a cooperative effort that could lead to the first wilderness-area designation in the state in a quarter-century.

"Glaciers on the iconic Teton Range are shrinking, researchers say, joining a growing list of glaciers in North America and beyond that are losing their surface area and potentially reducing the water supply for nearby regions."

"Eighteen cattle likely died of selenium poisoning near a southeastern Idaho phosphate mine, the latest livestock deaths in a region rich in phosphates where a legacy of pollution has killed horses and hundreds of sheep since the 1990s."

"After four years of negotiations, Utah and Nevada officials have created a draft agreement for management of the controversial Snake Valley aquifer straddling both states."

"As it races to replenish phosphate supplies for its weed-killing cash machine Roundup, Monsanto Co. insists its history of polluting southeastern Idaho’s high country shouldn’t prevent it from digging fresh open pits here."

"Part of the Nevada Test Site that hosted nuclear blasts in the past has been closed to avoid a costly cleanup of contaminated soils."