WHAT WE KNOW AND DON’T KNOW ABOUT GREAT SALT LAKE DUST

The Great Salt Lake (GSL) has been shrinking for over 30 years due to a combination of drought, climate change, and unsustainable water use for agriculture, municipal, and industrial purposes. As the lake recedes, more than 800 square miles of lakebed have been exposed, resulting in dust emissions that are transported into surrounding communities. This presentation will provide an overview of current knowledge regarding GSL dust, including the meteorological drivers, locations and characteristics of dust hotspots, the geochemistry of the dust, the bioavailability of metals, and methodologies for identifying contaminants of potential concern.

A key focus will be on identifying significant data gaps, particularly due to the insufficient PM₁₀ monitoring network in northern Utah. Although the Utah Division of Air Quality operates a limited network of real-time and filter-based PM₁₀ monitors, most monitoring sites are located more than 15 miles from the lakebed. Additionally, elemental composition analysis of the PM₁₀ filters is rarely conducted. As a result, there are substantial uncertainties about the frequency of dust exposure, PM₁₀ concentrations in the most vulnerable communities, and the associated risks from potential contaminants. To address these gaps, we recommend a significant expansion of the PM₁₀ monitoring network, including additional sites along the lake’s periphery and in the most at-risk communities.