"A new concessions contract for businesses on the South Rim of Grand Canyon National Park will cost the park $100 million, an amount that could impact just about all operations in the park, Superintendent Dave Uberuaga said Wednesday. In the long run, however, the move stands to benefit both the park and its visitors, observers believe."

"A civil defense official says that about 10 million gallons of mining acid leaked into a river that supplies water to tens of thousands of people."

"Imperial Metals describes substance spilled from dam as 'very close to drinking water.'"

"BAGHDAD — The crisis gripping Iraq escalated rapidly on Thursday with a re-energized Islamic State in Iraq and Syria storming new towns in the north and seizing a strategic dam as Iraq’s most formidable military force, the Kurdish pesh merga, was routed in the face of the onslaught."

"With the removal of many dams, conservationists are seeing the return of the natural bounty that fed Native Americans and astonished European settlers."

"Pennsylvania has 86,000 miles of rivers, streams and creeks — a total length eclipsed only by the vast wilderness in Alaska."

"New herds of genetically pure wild bison may once again roam vast expanses of the American West where the iconic animal has been absent since the end of the 19th century, under a tentative plan federal officials advanced on Wednesday."

"Two years ago, Bill Orem and his team of researchers were setting up air monitors in the yards and on the porches of residents in Artie, a small Raleigh County community surrounded by mountaintop removal mines."

"For years, the U.S. Environmental Protection Agency has been frustrated in its efforts to pursue hundreds of cases of water pollution — repeatedly tied up in legal fights about exactly what bodies of water it has the authority to monitor and protect. Efforts in Congress to clarify the EPA's powers have been defeated. And two Supreme Court decisions have done little to decide the question."