In the domestic well study, James is focusing on arsenic, which she said has been gradually increasing in valley drinking wells over the past 50 years. Arsenic levels in San Luis Valley groundwater are “markedly higher than [in] many other areas of the U.S.,” according to James. She is also investigating ethnic disparities, as one study there showed Hispanic adults had higher levels of arsenic in their urine than non-Hispanic white adults did. (Hispanic people can be of any race or combination of races.)
James now aims to test 1,000 private wells in the valley to explore the connections between drought, water quality, and health. So far, she said, a small proportion of wells show elevated levels of heavy metals, including arsenic, uranium, tungsten, and manganese, which occur naturally in the soil. Unlike public water supplies, private domestic wells are not regulated, and they may go untested for years. James is offering participants free water testing and consultation on the results.
In Conejos County, John Mestas’ daughter, Angie Mestas, jumped at the chance for a free test, which would cost $195 at a local lab. Angie, a 35-year-old schoolteacher, said she used a lifetime of savings to drill a drinking well on her plot of land, a wide-open field of chamisa with sweeping views of the San Luis Hills. But she won’t drink from it until she tests for arsenic and E. coli, which are common in the area. As she awaits test results, she has been hauling 5-gallon jugs of water from her father’s house each time she spends the weekend at her newly constructed yurt.
A Colorless, Odorless Threat
Meanwhile, Julie Zahringer, whose family settled in the valley from Spain nearly 400 years ago, has been watching water-quality trends firsthand. Zahringer, 47, grew up driving a tractor on her grandfather’s ranch near San Luis, Colorado’s oldest town — and hanging out in the lab with her mother, a scientist.