Federal air monitors routinely miss pollution, even refinery explosions; some firms get to pick 'cleaner' monitor sites

Communities rely on a federal air-monitoring network to raise the alarm when there are dangerous levels of pollution, but budget cuts and monitoring practices that favor polluters mean that Environmental Protection Agency air monitors sometimes miss even large disasters such as oil refinery explosions, and practices such as allowing companies to decide the placement of their own monitors make it less likely that pollution is detected.

"Over the past five years, the number of government monitors nationally has declined by 4 percent as state and local environmental agencies cut spending, according to EPA figures. Federal grants to state and local air-quality agencies have not increased in 15 years," Tim McLaughlin, Laila Kearney, and Laura Sanicola report for Reuters. "The EPA said it has improved the system despite what it acknowledged was flat funding for the past decade. The agency said it has replaced some labor-intensive, manual monitors with automatic monitors that provide round-the-clock, real-time data. The continuous monitors cost less to operate, but can also be less reliable than manual monitors in measuring particulate matter, according to EPA quality control audits."

The network has a lot of problems, according to academics and current and former regulators. "Monitors are sparsely and poorly placed; the program is underfunded; and the network is not equipped to meet current pollution threats," Reuters reports. "The monitoring program emerged piecemeal after the 1970 Clean Air Act, mainly to track acid rain, smog and ozone pollution. Those hazards have largely subsided, replaced by more localized threats including toxic compounds and particulate matter from a wide range of industry and natural hazards, such as wildfires.

Also, individual monitors are often inaccurate with wildly varying results, partly because state regulators have wide discretion over monitor placement, and often put them in "cleaner" areas, Reuters reports. Monitors are often programmed to work only once every 12 days (for example) to save on operating costs, and some monitors max out at too low a pollution level, so actual levels are much higher than those recorded. And when monitors do record excessive amounts of pollution, the EPA sometimes simply tosses the results for the purposes if its air-quality assessments, Reuters reports.