The Swinomish Tribe has been monitoring ambient air quality in partnership with EPA for more than 16 years.

“We’ve got two major oil refineries and a sulfur reduction plant right next to the reservation,” said Tony Basabe, Swinomish air quality analyst. “When I arrived in 1998, I thought we ought to monitor and find out what the refineries are doing to us.”

Swinomish has the only federally recognized nitrogen oxide (NOx) monitoring station north of Seattle, and until a few years ago was the only ozone monitoring station.

EPA grant funds support monitoring to characterize or manage specific known short- or long-term risks to environmental values such as human health risks, ecological risks, and cultural resources and values.

Swinomish has two monitoring stations: one near the tribal village, and one at the other end of the reservation, near the Swinomish Casino and Lodge overlooking March Point, the site of the two oil refineries.

While the air near March Point contains petrochemicals from the refineries, the pollution near the tribal village tends to contain the product of combustion: hydrochemicals from wood smoke, car and boat exhaust, and production from a logging yard.

The March Point monitoring station also is next to railroad tracks where trains carrying petroleum coke are expected to increase from two per day to four. The baseline data collected before the increase will help the tribe track the rise in pollution.

The tribe records real-time continuous pollution data for particulates, ozone and nitrogen dioxide, as well as meteorological data for wind speed and direction, temperature and relative humidity, barometric pressure, solar radiation and precipitation. The data goes into EPA’s Air Quality System (AQS) repository, which stores results from more than 10,000 monitors.