USDA Forest Service

Pacific Southwest Research Station

Pacific Southwest
Research Station

800 Buchanan Street
Albany, CA 94710-0011
(510) 883-8830
United States Department of Agriculture Forest Service. USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.

Secondary pollutant formation in the Lake Tahoe Basin

Principal Investigator:
Barbara Zielinska, Desert Research Institute
Alan Gertler, Desert Research Institute
Andrzej Bytnerowicz, USDA Forest Service-Pacific Southwest Research Station
Wendy Goliff, Center for Environmental Research & Technology, University of California, Riverside
Chad Praul, Environmental Incentives, LLC

Proposal [pdf]

Final Report [pdf]

Database [xlsx]

Project Summary

This study characterizes the precursors and pathways of secondary pollutant formation, including ozone (O3), secondary organic aerosol (SOA) and ammonium nitrate (NH4NO3) in the Lake Tahoe Basin. We selected a network of four strategic sampling sites inside the basin to collect samples for detailed speciation of volatile organic compounds (VOC) and carbonyl compounds and measured concentrations of ammonia (NH3), nitrous acid (HONO), nitric acid (HNO3), sulfur dioxide (SO2) and fine particulate NH4NO3 and ammonium sulfate ((NH4)2SO4) with a resolution of several hours. We also collected particulate matter (PM) 2.5 filter samples and measured PM, O3 and nitrogen oxide (NO/NO2) concentrations.

These data will be used for development of an air quality model to predict O3 and other secondary pollutants formation in the basin. The expected results from this proposed study will provide tools for evaluation of the present and future potential of O3, SOA and NH4NO3 formation as well as for interfacing with basin managers to support the development of science-based management strategies aimed at improving air quality and ecological sustainability of the Lake Tahoe Basin. In particular, the results of this study will be used to inform stakeholders which emissions should be more strictly regulated in order to attain air quality standards and reduce Total Maximum Daily Load (TMDL) pollutants delivered via the atmospheric deposition source category.