Guadalupe Mountains National Park Air Quality Information
A variety of air pollution sources affect air quality in Guadalupe Mountains NP, including power generating plants, natural gas compressor stations, local gas well flaring, and mobile and area sources in El Paso, Hudspeth, Culberson, Loving, and Reeves counties in Texas, and Otero, Lee, and Eddy counties in New Mexico, in addition to other areas of the Southwest. Imminent oil and gas field development on the Otero Mesa, west-northwest of the park, has the potential to significantly increase emissions in the area and contribute to visibility degradation in the park.
The air quality related values (AQRVs) of Guadalupe Mountains NP are those resources that are potentially sensitive to air pollution, and include vegetation, wildlife, water quality, soils, and visibility. At present, visibility has been identified as the most sensitive AQRV in the park; other AQRVs may also be very sensitive, but have not been sufficiently studied. Although visibility in the park is still superior to that in many parts of the country, visibility in the park is often impaired by light-scattering pollutants (haze).
The U.S. Environmental Protection Agency’s Regional Haze regulations require States to establish goals for each Class I air quality area to improve visibility on the haziest days and ensure no degradation occurs on the clearest days. As part of the Interagency Monitoring of Protected Visual Environments (IMPROVE) network, visual air quality in Guadalupe Mountains NP has been monitored using an aerosol sampler (1988-present), a transmissometer (1988-present), and an automatic 35mm camera (1983-1995). An analysis of 1990-1999 data indicates that visibility in the area is improving slightly on the clearest days, but degrading significantly on the haziest days. Clearest days are associated with high pressure winds from the northwest; planned oil and gas development on the Otero Mesa (west-northwest of the park) could contribute to visibility degradation in the park on those clearest days.
Surface waters in Guadalupe Mountains NP are likely to be well-buffered because of an abundance of base cations in the soils and rocks; therefore, waters are not likely to be acidified by atmospheric deposition of sulfur and nitrogen compounds. However, there may be areas in the park where rock is resistant to weathering and soils and water (e.g., in potholes) may be sensitive to inputs of acidic deposition.
Soils and vegetation in the park may be sensitive to nutrient enrichment from nitrogen deposition. In some parts of the country, nitrogen deposition has altered soil nutrient cycling and vegetation species composition; native plants that have evolved under nitrogen-poor conditions have been replaced by invasive species that are able to take advantage of increased nitrogen levels.
Estimates of total nitrogen and sulfur deposition can be made by adding wet and dry deposition. Wet deposition has been monitored in Guadalupe Mountains NP since 1984 as part of the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). The site ID is TX22. Rates of atmospheric deposition of nitrogen and sulfur in rain are relatively low in Guadalupe Mountains NP. However, a trend analysis of 1990-1999 data indicates that both wet sulfate and wet nitrate deposition rates are increasing. Dry deposition estimates are not available for the area.
Several plant species that occur in Guadalupe Mountains NP, including Pinus ponderosa (ponderosa pine) and Rhus trilobata (skunkbush), are known to be sensitive to atmospheric ozone. Tropospheric (ground-level) ozone concentrations were monitored in Guadalupe Mountains NP from 1987-1992. Recent ozone estimates are available from the National Park Service Air Atlas website, and indicate that ozone concentrations and doses are not currently at levels known to cause injury to vegetation. However, at ozone monitoring sites to the west, including Chamizal National Memorial and Chiricahua National Monument, ozone concentrations and doses are increasing, and may also be increasing at Guadalupe Mountains NP. No surveys to assess vegetation injury have been performed in the park.
Additional information on in-park emissions at Guadalupe Mountains NP is available in 2001 Air Emissions Inventory- Guadalupe Mountains National Park (June 2003)