"Among air experts, it's an open secret: federal and state officials grossly undercount a crucial type of air pollution, often by an order of magnitude and particularly in areas like Houston with its major concentrations of petrochemical plants."

"Houston's biggest sources of smog-forming pollution may avoid tens of millions of dollars in penalties for the region's failure to achieve federal clean-air goals."

"ALBUQUERUQE, N.M. -- With much of New Mexico still stuck in severe drought, water managers are improving miles of channel along the Rio Grande so more winter and spring runoff can find its way to Elephant Butte Reservoir."

"TEXAS CITY — A fire at BP's Texas City refinery sent a large plume of black smoke over the industrial sector of the city. The fire broke out at about 1:30 p.m. and was out by 3:05 p.m., BP officials said."

"SANTA TERESA, N.M. -- An unknown hazardous material sickened about 200 people Tuesday just northwest of El Paso, Texas, as some workers in the industrial area where the substance released described feeling a burning sensation on their skin, according to New Mexico authorities."

"SUMNER, Texas -- Oil has long lived in harmony with farmland and cattle across the Texas landscape, a symbiosis nurtured by generations and built on an unspoken honor code that allowed agriculture to thrive while oil was extracted."

"Fifteen residents of Corpus Christi, Texas -- so sickened by pollution they have been deemed crime victims -- are asking a federal judge to force Citgo Petroleum Corp. to set up multimillion-dollar trust funds to cover medical and relocation costs, in a case with national ramifications."

"FLAGSTAFF, Ariz. — Klee Benally, a member of the Navajo tribe, has gone to the mountains just north of here to pray, and he has gone to get arrested. He has chained himself to excavators; he has faced down bulldozers. For 10 years, the soft-spoken activist has fought a ski resort’s expansion plans in the San Francisco Peaks that include clear-cutting 74 acres of forest and piping treated sewage effluent onto a mountain to make snow."

"Port Arthur, Tex. -- The Valero oil refinery looms over the small streets of this blighted port city. A vast maze of pipes and vats and boilers, the refinery traces its rootsback 111 years, to just months after the historic Spindletop gusher that triggered the Texas oil rush."

"BLOOMING GROVE -- On one side of a gravel road in Navarro County, an overgrazed pasture has been cropped to the dirt. Across the road, a surviving patch of Blackland Prairie that has been reseeded with native grasses is covered with a cornucopia of 170 plant species that together comprise prime habitat for bobwhite quail -- if only they could get there."

"AUSTIN -- Exxon Mobil Corp. has reported inadvertent emissions of large amounts of pollutants at its flagship refinery near Houston."

"For decades, cowboys known as 'tick riders' have patrolled the U.S.-Mexico border to prevent cattle carrying 'fever ticks' from entering."

"OKLAHOMA CITY (AP) — High temperatures and an ongoing drought are having an impact on more than just crops and livestock. State health officials say they are also creating ideal conditions for the growth of a tiny, single-cell organism that lives in Oklahoma's rivers, lakes and ponds and can cause a disease that is almost always fatal."

"The Canadian pipeline company TransCanada has quietly begun construction of the southern leg of the controversial Keystone XL pipeline, installing segments near Livingston, Texas, company officials confirmed Thursday."

"The Arizona city already logs more days over 100 degrees than any U.S. city, and climate researchers predict Phoenix will grow hotter still in the coming decades. Planners are taking the projections seriously, and are looking for ways to adapt the city and its residents to a hotter, drier reality."