Air Monitoring Stations
ORCAA and Ecology operate and maintain meteorological sensors (wind speed, wind direction, temperature, and relative humidity) and air quality monitors throughout ORCAA’s six-county region. In addition to the permanent air monitoring stations, ORCAA is deploying self-contained air quality SensWA sensors in each county. These sensors were developed by Ecology and provide near real-time PM2.5 monitoring. You can find all of ORCAA’s monitoring stations and SensWA sensors on the map here.
Cheeka Peak Observatory (CPO)
NCore and IMPROVE monitoring network site
The Cheeka Peak Observatory has been home to air monitoring activities since the 1980s. Researchers from the University of Washington maintained an atmospheric monitoring station here from circa 1983 until 2010, when ORCAA took over operation of the site using funding from EPA. EPA supports the site as part of the nationwide NCore network. The Makah Tribe moved their IMPROVE network air monitoring site to Cheeka Peak in the same year. The IMPROVE and NCore air monitoring networks monitor different pollutants. The two network sites complement each other and provide a long-term record of chemically speciated atmospheric particulate, trace gases, and meteorological data.
Location: remote site above Neah Bay, WA
| Pollutant | Monitor |
| PM2.5 | Nephelometer (M903) |
| Ozone | Teledyne FEM ozone analyzer (T400) |
| Sulfur Dioxide (SO2) | Teledyne FEM SO2 analyzer (T100U) |
| Carbon Monoxide (CO) | Teledyne FEM CO analyzer (T300U) |
| Oxides of nitrogen (NOy) | Teledyne FEM NOy analyzer (T200U) |
| Meteorology (WS/WD, Temp, Pressure, RH) | RM Young ultrasonic anemometer (05103), RM Young Temperature probe (41342VF), RM Young Pressure Port (61002), RM Young RH probe (41382VF) |
James P. Werner Air Monitoring Station in Lacey
ORCAA began monitoring PM10 at Mt. View Elementary School in 1988. Air monitors were originally housed in the school library. Ten years later, ORCAA staff built a separate monitoring shelter on the school’s athletic field. In 2025, a brand-new air monitoring shelter (pictured below) replaced the older one. ORCAA named the new shelter the James P. Werner Air Monitoring Station in honor of ORCAA’s first Senior Air Monitoring Specialist, who was employed by ORCAA from 1981 to 2012. In addition to monitoring ambient PM2.5, ozone, and black carbon, this site also serves as a testing platform for SensWA air sensors and has been home to special, short-term air monitoring projects over the years.
A county-wide saturation study was completed in 2021 to identify the best location for the county’s official air monitoring station. The Mountain View Elementary School site was verfied as the best location.
Location: 1900 College St SE, Lacey, WA
| Pollutant | Monitor |
| PM2.5 | Beta Attenuation Monitor (BAM 1022) / Nephelometer (M903) |
| Black Carbon | Aethalometer (AE33) |
| Ozone | Teledyne FEM ozone analyzer – T400 (seasonal) / 2B Model 202 ozone monitor (year-round) |
| Wind direction & speed | RM Young anemometer |
Blue Heron Middle School in Port Townsend
ORCAA began monitoring at the school in November 1995. The site utilizes a Nephelometer to measure PM2.5 levels in the community.
A county-wide saturation study was completed in 2016 to identify the best location for the county’s official air monitoring station. The Blue Heron Middle School site was verfied as the best location.
Location: 939 San Juan Ave, Port Townsend, WA
Port Angeles Fire Station
ORCAA moved the Clallam County air monitoring site from Stevens Middle School to the Port Angeles Fire Station in 2015 after completing a saturation study that found this site to be more appropriate for the region. The site utilizes a Nephelometer to measure PM2.5 levels in the community.
A county-wide saturation study was completed in 2015 to identify the best location for the county’s official air monitoring station. The Port Angeles Fire Station site was verfied as the best location.
Location: 102 E 5th St, Port Angeles, WA
Shelton Fire Station
Before April 2011, the Mason County air monitor was at Mason General Hospital. It was moved due to construction at the hospital. The site utilizes a Nephelometer to measure PM2.5 levels in the community.
A county-wide saturation study was completed in 2024 to identify the best location for the county’s official air monitoring station. The Shelton Fire Station site was verfied as the best location.
Location: 122 W. Franklin St., Shelton, WA
Harbor High School in Aberdeen
ORCAA began monitoring at the school in August 2002. The site utilizes a Nephelometer to measure PM2.5 levels in the community.
A county-wide saturation study was completed in 2026 to identify the best location for the county’s official air monitoring station. The Harbor High School site was verfied as the best location.
Location: 359 North Division St, Aberdeen, WA
Pacific County PUD in Raymond
ORCAA moved the Pacific County air monitor from South Bend High School in July 2019 due to construction at the school. The site utilizes a Nephelometer to measure PM2.5 levels in the community.
Location: 503 4th St, Raymond, WA