Mount Rainier National Park
Tahoma Woods IMPROVE Site
The National Park Service (NPS) Air Quality Research Program involves an extensive network of monitoring for pollution, visibility conditions, and biological effects in NPS units. At Mount Rainier the monitoring program has included: -use of cameras for measuring visibility -fine particulate monitors for identifying the causes and sources of visibility impairment -ozone monitors for establishing baseline conditions, assisting the ozone effects research, measuring precipitation chemistry, and evaluating new pollution sources. Visibility impairment at Mount Rainier National Park is among the highest of all sites monitored in the west. The NPS Visibility Monitoring Program provides access to the most current data on visibility monitoring in the park http://www2.nature.nps.gov/ard/vis/vishp.html.
The park is part of the Interagency Monitoring of Protected Visual Environments (IMPROVE) network with a station located at Tahoma Woods. Fine particulates are measured at Tahoma Woods and at Paradise. Photographic documentation of visibility has been conducted at Paradise, Camp Muir, and at the Mt. Fremont and Tolmie Peak Fire Lookouts. For additional information on visibility impairment go to http://www.epa.gov/oar/visibility/what.html
Most park lakes and ponds are sensitive to atmospheric deposition inputs as they have little or no buffering capacity. Most lakes have have been measured well under 100 ueq/L for ANC, and several lakes on the west and south sides of the park have ANC below 50 ueq/L. Approximately 48% of park lakes have been inventoried at least once.
Water quality for approximately 20 of the major streams in the park has been inventoried. Of these, 10 sites have been documented as extremely sensitive. Spring snowmelt or late summer storms can cause highly acidic deposition events which can affect the aquatic ecology of these surface waters.
Studies conducted at Eunice Lake in the northwest corner of the park, documented increased levels of sulfate during the spring, early summer snowmelt period. The chemistry of bulk precipitation collected at Paradise has been measured since 1986. Precipitation samples taken at Paradise have shown higher than background levels of sulfates. The chemistry of cloudwater samples taken at Paradise have shown some of the lowest levels of pH and highest levels of acidity of any taken in the state.
Mount Rainier National Park established a National Atmospheric Deposition Site within the park in 1999. Precipitation samples are collected and chemistry analyzed. Data is available on the National Atmospheric Deposition Program web site at http://nadp.sws.uiuc.edu./nadpdata/siteinfo.asp?id=WA99&net=NTN. Visible injury to plants from ozone has been documented from concentrations as low as 60 parts per billion (ppb). Ponderosa pine in southern California has a threshold for visible damage at approximately 80 ppb. Scientists believe that any increase in ozone levels above background (clean air) will have some adverse effect on individual leaves of at least some species.
Clean air is defined as ozone concentrations ranging from 15 to 30 ppb. Elevated ozone levels (above 80 ppb) were measured at Longmire in the southwest section of Mount Rainier National Park during the summers of 1987 and 1988. Values above 80 ppb were not uncommon at an ozone monitor at Carbon River in the northwest corner of the park during 1989 to 1992 and there were a few readings above 100 ppb. Similar values have been measured at Tahoma Woods while ozone levels at Paradise have, on some days, have been the highest recorded in the state.
High levels of ozone have also been measured in rural areas surrounding the park in Enumclaw (10 miles north of the park), Cedar River (30 miles north of the park), and Pack Forest (15 miles west of the park). Chlorotic foliar spotting on the foliage of ponderosa pine at Pack Forest has been reported and scientists hypothesized that ozone-sulfur dioxide synergism was responsible for the damage.
Ozone impacts on sensitive vegetation in the Pacific Northwest have received little attention until recent years because of the relatively low levels of ozone in the area. Ozone sensitive species in Mount Rainier have recently been identified and are being monitored in selected areas. Passive ozone monitors are also used to document ozone levels at sites where vegetation plots have been established. In addition, continuous ozone monitors are in operation at Tahoma Woods and Paradise. A guide to ozone injury in vascular plants of the Pacific Northwest is now available online at http://www.fs.fed.us/pnw/pubs/gtr_446.pdf. This document is the result of recent NPS and US. Forest Service studies of ozone sensitive plant species.
An emerging issue of great concern is the degree of risk that park resources may be experiencing from the long- range transport of airborne contaminants. The contaminants of interest are a broad range of compounds and elements that are sometimes called Persistent Bioaccumulative Toxics or PBTs. This group contains a variety of persistent organic pollutants (POPs) such as PCB, DDT, HCH as well as elements such as mercury (Hg). These materials are direct or indirect products of human industrial activity and can be transported thousands of miles in the atmosphere either in the gas phase or as fine particles. In some cases they can be deposited to aquatic or terrestrial ecosystems and then be re-emitted due to biophysical processes – only to continue their long journey through the atmosphere. Some of these materials have specific properties that permit them to move pole-ward or up in elevation following temperature gradients and they may come to accumulate, preferentially, in colder areas of the global environment. This phenomenon has been termed “cold condensation” and has been observed for lighter congeners of PCB, HCHs and even mercury. Hence, it is expected that high elevation and latitude ecosystems may be at greater risk due to the accumulations of toxicants that behave in this way.
There is very little information on the accumulation of any of these toxic materials in the natural environments of the U.S. or elsewhere in the world. The National Park Service is initiating an air-toxic focused assessment program based in the National Parks of the western United States to provide spatially extensive, site specific, and temporally resolved information regarding the exposure, accumulation and impacts of airborne contaminants in these ecosystems for the purpose of instituting long-term monitoring.
