President Trump has granted two-year reprieves to dozens of coal-fired power plants for meeting tougher emission standards, including one in Arizona.

Grass fires burn far more American homes each year than forest fires. In southern Arizona, communities fight fires that never ...

The extra time and effort spent on proper tree planting is a small investment for the long dividends paid by a tree in the ...

Arizona’s air is getting cleaner—but not clean enough. A new report from the American Lung Association shows some wins for ...

The project is taking advantage of demand expected to arise at the opening of TSMC's Arizona fabrication plant.