Drought and Arsenic in the San Luis Valley, CO

Over 800 private well owners were engaged and successfully collected 739 groundwater samples. These samples were analyzed for a panel of metal and ion elements (arsenic, antimony, barium, chromium, cadmium, calcium, cobalt, copper, iron, lead, magnesium, molybdenum, manganese, nickel, potassium, sodium, strontium, sulfur, thallium, tungsten, uranium) by Dr. Fendorf and colleagues. Results were provided to participants in an individualized report, including comparison to EPA drinking water standards and interpretation of results by research staff supervised by Dr. James. Results were accompanied by an information sheet on reducing cumulative metals exposure and information for specific metals found to be elevated. These samples have been successfully matched with well permits maintained by the Colorado Division of Water Resources, which provide information on latitude/longitude coordinates and well depth.

The cumulative efforts of groundwater sampling in Phase I has led to increased awareness of environmental exposures in San Luis Valley communities. An introductory report to the project has been created for the community – describing our interest in metals exposure in the San Luis Valley, the prevalence of elevated metals across the cohort, brief descriptions of potential health effects, and ways to reduce overall exposure to metals from drinking water. Additional reports are being developed for specific metals of concern to elaborate on potential health effects, spatial modeling of the metal across the region, and a comparison to previous government estimates on exposure.

Approximately forty participants from Phase I were recruited for quarterly sampling for the metals panel analysis, and additional analysis to analyze for dissolved hydrogen and oxygen isotopes. Results reports are provided for each sampling timepoint along with a temporal comparison for levels of arsenic, manganese, and uranium.

Information coming soon!

Exposure information from the Phase I and II regional sampling, historic water data, and geospatial modeling will be used to quantify exposure to heavy metals from drinking groundwater. Combined with ICPMS results to analyze heavy metals in samples from the San Luis Valley Diabetes Study (10.1093/oxfordjournals.aje.a115134), Dr. Gribble will lead epidemiologic modeling.

Results and achievements will be accomplished in years four and five of our grant funding. More information coming soon!

Al Fatta A, Vajedian S, Smith R. Assessing Aquifer Properties and Groundwater Storage Change in the San Luis Valley, Colorado from In-situ and InSAR Data. Presented at: AGU Hydrology Days; March 2023.

Southern J, Fendorf S. Deciphering the role of redox conditions on arsenic contamination in the San Luis Valley, Colorado. Presented at: Stanford Student Symposium; October 2023.

Stoll N, James K. Drought, Heavy Metals, and Water Quality.; 2023.

Vajedian S, Smith, Ryan. Exploring functional controls on the delayed response of deformation to changes in groundwater levels. Presented at: AGU Fall Annual Meeting; December 2022.

Liebson R, Fendorf S. Geothermal contributions to groundwater arsenic contamination in the San Luis Valley, CO, USA. Presented at: Stanford Student Symposium; October 2023.

Stoll N, Gribble M, Smith R, James K. Investigating cliamte change-induced drought as a driver of heavy metals exposure in a rural community. Presented at: Colorado Environmental Health Association; October 2023.

Smith R, James K, Lopez A, Al Fatta A, Vajedian S, Fendorf S. Summary of remote sensing hydrology lab research in the San Luis Valley. Presented at: Rio Grande Roundtable; October 2023.

Smith R, James K. The impacts of drought on aquifer health. Presented at: Rio Grande Roundtable; October 2023.

Vajedian S, Smith R, Maurer J. Unraveling the Complex Interplay of Groundwater Dynamics and Land Subsidence in the San Luis Valley, Colorado. Presented at: AGU Fall meeting; December 2023.

Stoll, Nicholas, James K. Using community engaged research to investigate heavy metal exposure from groundwater. Presented at: Public Health in the Rockies Conference; September 2023.

Stoll N, James K. Using community engagement to investigate environmentla health while navigating local dynamics on climate change and science. Presented at: Colorado Environmental Health Association; October 2023.

Honeyman A, Fendorf S, Lopez A, Blythe C, James K, Smith R. Using statistical and machine learning to explain the threat of arsenic in groundwater in the San Luis Valley, Colorado, USA. Presented at: July 2023.