Nogales-area group and University of Arizona launch AirSmart sensor network to track air quality ahead of mining activity

The Calabasas Alliance and the University of Arizona on Feb. 5 announced AirSmart, a community-led air-monitoring program that will place real-time air-quality sensors in Rio Rico, Nogales and Patagonia to establish baseline data and track changes as nearby mining activity ramps up.

The program, Calabasas Alliance president Robin Lucky told the council, will “place advanced air monitoring sensors around locations in Santa Cruz County” and publish the data on an online dashboard that will be open to the public. Assistant Professor Chris Lim of the UArizona Mel and Edith Zuckerman College of Public Health said the plan is to begin equipment installations within about two weeks.

The work matters because, Lim said, “Santa Cruz County is in nonattainment for both PM 2.5 and PM 10,” and local air quality can vary sharply over short distances and time periods. Lim said mining development and associated truck traffic could increase particulate matter and heavy-metal pollutants such as lead and manganese that have documented health risks.

Lim described a two-tier sensor approach: inexpensive citizen-operated sensors (PurpleAir) that cost about $300 per unit and can deliver dense, hyperlocal PM readings, and more expensive research-grade units (installed on rooftops or schools) that can cost from about $3,000 to $5,000. He said a gas-capable monitor that includes ozone and nitrogen dioxide measurement runs roughly $12,000 per unit. The project team expects to deploy about 20 sensors feeding a public dashboard and to provide background guidance on health impacts and color-coded levels for public interpretation.

Lucky emphasized the volunteer nature of the Calabasas Alliance: “The Calabasas Alliance will receive no compensation for this program. We are an all volunteer 501(c)(3) whose mission is to protect the air, water, and land in Santa Cruz County.” She introduced UArizona graduate students and faculty who will support sensor installation and data management.

Council members and staff questioned placement, security and costs. Councilman Doyle asked whether sensors should be roof-mounted or street-level; Lim replied that street level is ideal for measuring human exposure but theft and vandalism are concerns, so elevated mounting out of reach is preferred. Lim also said some sensor networks charge a recurring fee (he cited a roughly $500-per-year platform fee for one module) and noted that PurpleAir-style units need only electricity and internet.

City Manager Joe Kramer told presenters the city will cooperate where feasible: “We can certainly do that,” he said when asked about placing sensors on city property; staff later said they would coordinate sites and work with county and university partners. Presenters said they had already discussed coordination with the mine and county representatives and hoped to avoid redundant monitoring near similar sites.

The group said the data will be posted in real time and used to identify spatial patterns, short-term peaks and trends that federal monitors miss. Lim pointed to other projects in Arizona where inexpensive sensors revealed localized peaks that the single federal monitor did not show, and said that hyperlocal data can inform public-health warnings and school protections.

Next steps: presenters said installations start within weeks and that the dashboard and explanatory materials (including a color-coded chart for health guidance) will be available for public use. The presenters asked the council for permission to use suitable city property for sensors and for help identifying stable, elevated mounting points with electricity and internet.

The council did not take a formal vote on the presentation but signaled willingness to coordinate with the Calabasas Alliance and UArizona as the project proceeds.