While most people assume that well water is clean and safe, a recent study by the U.S. Geological Survey shows that one out of every five wells providing public drinking water contains at least one contaminant at levels of potential health concern. The USGS sampled 932 public wells across the country for the study.

Animal manure, a byproduct as old as agriculture, has become an unlikely modern pollution problem, scientists and environmentalists say. The country simply has more dung than it can handle: Crowded together at a new breed of megafarms, livestock produce three times as much waste as people, more than can be recycled as fertilizer for nearby fields.

We toss more than 20 million tons of sodium chloride on our roadways every winter. That's about 13 times more salt than is used by the entire food processing industry. Salt lowers the freezing temperature of water and thus melts street-clogging snow and ice.

Wyoming is close to having its first new standards for water wells in more than 35 years. The rules are expected to take effect this spring or summer and would apply to all new residential, industrial and municipal water wells in the state. The rules would impose tougher standards to keep pollution and bacteria from contaminating groundwater.

More than 100 people gathered Monday night in Nunn to plead with representatives from the Environmental Protection Agency to put a stop to a permitting process that marks the initial stages of a proposed uranium mine near the town.

Across vast regions of the country, gas companies are using a technology called hydraulic fracturing to produce natural gas from previously untapped beds of shale. The push has been so successful that the country’s potential gas reserves jumped by 35 percent in two years.

A new wave of testing by the U.S. Environmental Protection Agency has found that 79 percent of the wells tested north of a World War II-era copper mine in Nevada have dangerous levels of uranium or arsenic or both that make the water unsafe to drink. The source of the pollution is a groundwater plume that has slowly migrated from the 6-square-mile mine site.

Bernice and Jerry Angely like to show visitors the singed T-shirt a friend was wearing when their water well exploded and shot flames 30 feet high. The friend wasn't hurt.

A Colorado official says the state supports oil shale development but wants more information about the potential impacts on water, the environment and public health before commercial development begins. Bob Randall of the Colorado Department of Natural Resources says the state also wants the federal government to proceed slowly with further leases on public land for research and development.