Mount Rainier is a Class I air quality area. The Clean Air Act requires federal land managers to protect park air quality related values, which include scenic, natural, and cultural resources. Air quality impacts have occurred in the park due to recreational use and are a concern, as are regional effects on the park. Mount Rainier is an active volcano that presents considerable hazards to park visitors, employees, and infrastructure.
The primary geologic hazard is from debris flows. Many of the park's developed sites are located on debris flow deposits in valley bottoms, and 7 of 23 developed sites in the park are in a debris flow hazard zone with an estimated recurrence interval of less than 100 years (Scott et al. 1992; Hoblitt et al. 1995) Other potential hazards are pyroclastic flows, ash fall, and lava flows (if Mount Rainier erupts), as well as snow avalanches, rock falls, and landslides. About 149 exotic (nonnative) plant species are found in the park. Most nonnative species grow in disturbed habitat below 5,500 feet.
Their presence is the result of human intervention, not natural migration. About 10% of the species are aggressive, capable of invading undisturbed natural areas and dominating native plant communities. The water resources in the park are protected and managed under the Federal Water Pollution Control Act Amendments of 1972, and the Clean Water Act of 1977. NPS Management Policies also require the protection and conservation of water quality in the park.