Air Quality

     Director:  Vicki Fisher
     Air Quality Contact:  Morgan Twombly                     
     Main Office:
         300 Sixth Street
         Rapid City, SD  57701
     Telephone:  605-394-4120

Air Quality

     Email Us

The Air Quality Division goals are to maintain compliance status with the United States Environmental Protection Agency’s National Ambient Air Quality Standards, and to prevent adverse health and environmental effects that result from fugitive dust emissions and smoke from wood burning and open burning. These goals are achieved and maintained through the development and implementation of programs of education, air pollution prevention, abatement and control.

Click here to see the current Air Quality Index
Click here to see the DANR Air Quality Index

Rapid City has a history of poor air quality which do not meet the standards set by the Clean Air Act. The poor conditions are associated with a number of pollutants, namely large particulate matter such as dust (PM10). Particulate matter consists of the solid particles and liquid droplets found in the air. Individually, these particles are droplets that are invisible to the naked eye but collectively they can appear as clouds or a fog-like haze.  Some contributing factors to our poor air quality include industrial mining operations, construction sites, wind-blown dust, tilled fields, unpaved roads, vehicles, crushing and grinding operations and burning of wood. In addition to anthropogenic (man-made) factors, the local topography and weather conditions also affect our air quality.

High winds cause air quality problems if conditions have been dry for several days and sustained winds exceed 20 mph and peak winds exceed 40 mph. These kinds of high winds usually come from the northwest as a cold front moves through the region. Dust from quarrying operations and other activities that expose soil is picked up by the high winds and dispersed throughout west Rapid City. A Natural Events Action Plan for high winds was developed for Rapid City to control fugitive dust emissions within the Air Quality Control Zone.

Temperature Inversions
Temperture Inversions

Temperature inversions are instances in which warm air traps the stable, cool air below, meaning pollutants cannot dissipate into the upper atmosphere. Inversions often occur at night and are characterized by wind speeds less than 8 mph and air which around is 32 °F or colder.

 Inversions are exacerbated by the bowl-like topography of west Rapid City. The surrounding mountain ridges trap pollutants close to the ground, acting like a wall so that pollutants cannot spread out laterally. Poor air quality results if these inversion conditions persist for more than 12 hours. At night when we are burning wood, the smoke gets trapped by the inversion, forcing us to breathe in pollutants such as PM10, PM2.5, CO2, Methane and carcinogens (cancer causing chemicals) such as benzene and formaldehyde. Therefore, it is especially important to abide by good burning practices (A Good Neighbor's Guide to Woodburning in Rapid City and EPA's Burn Wise Program).

Login Form