A Ninth Circuit panel revived a Trump-era Clean Water Act regulation that states could not consider a project’s effects on air emissions and road traffic congestion, finding the lower court lacked authority to vacate the rule without finding it unlawful. Read more»

Pima County issued a public health advisory for residents living within a one-mile radius of Tuesday's chemical spill on Interstate 10, advising them to seek medical attention if any breathing problems arise. Read more»

El Condado Pima emitió un aviso de salud pública para los residentes que viven dentro de un radio de una milla del derrame químico del martes en la Interestatal 10, aconsejándoles que busquen atención médica si surge algún problema respiratorio. Read more»

Salt River Project has partnered with Clēnera, a private renewable energy company, to bring Arizona its largest solar plant on 2,400 acres of private land northwest of Flagstaff by 2024. Read more»

The Biden administration is not planning to ban gas stoves, but comments from a commissioner on the CPSC about gas stoves being a “hidden hazard” and that “products that can’t be made safe can be banned” provided just enough fuel to stoke fear and outrage. Read more»

As communities prepare for a massive influx of federal funding to support urban forestry, their leaders say the tree canopy that grows to maturity 50 years from now will need to be painted with a different palette than the one that exists today. Read more»

A few cargo containers and a modest tower bristling with equipment on the campus of the University of Arizona's Tech Park might be the key to solving a major problem in modern life: the overwhelming production of carbon dioxide for transportation, plastics, and thousands of consumer products. Read more»

Once in a decade, as stated by the Clean Air Act, each state is required to assess airshed pollution in national parks and wilderness areas. This regional haze planning process is a rare and vital chance to clean up the air for Arizonans while lowering our state’s emissions that worsen climate change. — Catalina Ross, Sierra Club Read more»

Pima County will track air pollution in its most affected areas with the help of a $488,000 three-year federal grant. About 30 air pollution sensors will be set up at schools in the Tucson, Flowing Wells, Vail and Sahuarita Unified Districts, among others. Read more»

As wildfires continue to burn in parts of the United States - with more than 56,000 fires burning nearly 7 million acres nationwide this year - state public health officials and experts are increasingly concerned about residents’ chronic exposure to toxin-filled smoke. Read more»

High heat and air pollution are each problematic for human health, particularly for vulnerable populations such as older adults - and the risk of death on extra-hot and polluted days is about three times greater than the effect of either high heat or high air pollution alone. Read more»

La contaminación del aire en el área metro de Tucson está en niveles dañinos el miércoles. Los residentes deben limitar las actividades al aire libre, según el Condado Pima. Read more»

Air pollution in the Tucson metro area reached harmful levels on Wednesday, with high concentrations of ozone over the city. Residents should limit outdoor activities, Pima County officials said. Read more»

Las partículas que flotan en el aire alrededor del Condado Pima alcanzaron niveles tan altos el lunes que el Departamento de Calidad Ambiental emitió un "aviso de alta contaminación," recomendando a las personas en riesgo que reduzcan sus actividades al aire libre. Read more»

Particulates floating in the air around Pima County reached such high levels Monday that the Department of Environmental Quality issued an "high pollution advisory," recommending at-risk individuals reduce their outdoor activities. Read more»