"After Pittsburgh City Council gave final approval Tuesday to a ban on natural-gas production in the city, industry opponents vowed to press for similar prohibitions at the Allegheny County and state levels."

The possibility of producing natural gas from shale formations beneath central Quebec is raising the same debate about its perils and promises as is raging in U.S. states.

Residents of Joliet, Illinois, worry about what coal ash in huge pits will do to their wells -- and their health.

The Great Lakes, America's largest supply of fresh water, and surrounding forests, wetlands, and waterways are threatened by new mining of copper and nickel.

"In a case being followed closely by some Marine veterans and their families, a federal judge has denied the Navy's request to dismiss a civil case regarding an Iowa woman's exposure to contaminated water at Marines Base Camp Lejeune, N.C."

"Arizona Public Service Co. plans to partially close one of the nation's dirtiest coal-fired power generators, the Four Corners Power Plant in New Mexico, company officials said Monday."

"Canada's lakes and rivers are awash in harmful contaminants, but new documents warn the federal government's murky understanding of the problem is putting the country at risk."

New York state is strewn with abandoned wells -- the relics of drilling booms before the current gas bonanza. Their owners are long gone, but they have left a legacy of pollution, sticking taxpayers with the cleanup costs.

Low-income residents of small towns in California's San Joaquin Valley, often Latinos, suffer from unhealthful drinking water caused by the valley's booming agriculture. Now some activists are fighting back.

Many cities in Wisconsin still face toxic contamination from municipal gas plants closed six decades ago. Similar sites are found in other states.

"The Chesapeake Bay does not like your lawn. That green grass is probably coated with pesticides and fertilizers and studded with pet poop. All that washes off in the rain and causes environmental problems downstream in the Chesapeake."

"The Canadian government [Tuesday] turned down a proposal for a gold-copper mine in central British Columbia due to environmental concerns, while authorizing a second gold-copper mine on B.C.'s northwest coast to proceed."

"Two chemical manufacturers are seeking an exemption from new rules in Wyoming that require public disclosure of the chemicals used in hydraulic fracturing, a controversial natural gas drilling process suspected of polluting groundwater."

"The coal industry, facing a host of new health and safety regulations, is spending millions of dollars in lobbying and campaign donations this year to influence the makeup of the next Congress in hopes of derailing what one industry official called an Obama administration 'regulatory jihad.'"

Massachusetts has reduced its mercury emissions, but the mercury polluting its ponds may be coming from halfway around the globe.