Darwin-4th Avenue Air Monitoring Station, Darwin, California | US EPA AQS Network

Darwin-4th Avenue is an air monitoring station located at 4th Avenue in Darwin, California, United States. It is part of the California Air Resources Board's monitoring network, which feeds into the US EPA Air Quality System (AQS). The station is operational and serves the Inyo County area. The station operates under the regulatory framework of the US Clean Air Act and the EPA's ambient air quality standards. As a fixed-site monitor, it typically measures criteria pollutants such as ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. The California Air Resources Board ensures data quality and siting representativeness to meet federal requirements. This station provides critical air quality data for the remote community of Darwin and surrounding areas. Its location in a rural setting helps characterize background pollution levels and long-range transport. The data supports public health advisories and regulatory compliance for the region.

Darwin is a small community in Inyo County, California, located in a desert valley near the Sierra Nevada. The area experiences dry conditions and occasional inversions that can trap pollutants. Air monitoring here helps assess impacts from local sources like mining and transportation, as well as regional haze. The station's siting is representative of rural background conditions, complementing urban monitors in the state.