Conclusions

After decades of seeking water rights from the Colorado River, Navajo Nation sought the help of the United States in the Supreme Court case, Arizona v. Navajo Nation (Smith et al., 2023). In June 2023, the US Supreme Court denied their request for the “United States to assess what water rights it holds in trust on the Tribe’s behalf pursuant to the Treaty of 1868” (Kavanaugh, & Gorsuch, 2023, p.11). The Supreme Court asserted that the Diné people could rely on streams and groundwater on the reservation to fulfill their needs.

Furthermore, Uranium mining occurred all over the nation from 1948-2005. In 2015, the Gold King Mine Spill surged into the San Juan watershed, much of which is located on the Diné tribal lands. These events led us to wonder, is there water of sufficient quantity, quality, and accessibility to provide for the Diné?

In our surface water analysis of data from the EPA, we found many samples containing 1 or more contaminants exceeding the EPA’s safety limits. During the high flow of 2019, that level increased significantly during a 75 year flood event. As of 2022, the level for most heavy metals we observed had returned to acceptable limits. The exception was arsenic, which has continued to spike. In 2021, it spiked for unknown reasons.

In our groundwater analysis, we found water quality data from the EPA from 1998-2000, 15 years before the Gold King Mine Spill. We found many of the wells with heavy metals exceeding EPA limits of safety. Many of the wells were considered “some risk” and “more risk” by the EPA due to the presence of heavy metals.

In our analysis of water accessibility, we discovered that a high proportion, 57%-72% of the Diné, are considered vulnerable. Everywhere on the reservation, a majority of the population is at high risk to health impacts by heavy metals in the water.

What’s next?

Future studies can take our research further. First, there is a need to locate well data that is more recent, with data collected since the 2015 Gold King Mine Spill. Our study could not confirm or deny that the Gold King Mine spill impacted groundwater quality because our data ended in 2000. Additional on-the-ground testing of well and spring water is necessary for the data to be relevant to the Diné people.

Perhaps wells have been tested privately. Future projects could attempt to gather and consolidate private well data on a website so it is accessible to others on the reservation.

Second, more heavy metals can be analyzed. We started with 5 heavy metals for surface water and groundwater, but many more were included in our data sets. Arsenic and lead should be analyzed in groundwater because of the high health concerns and, after the Gold King Mine Spill, arsenic and lead were present in surface water, far exceeding EPA safety limits. Similarly, thorium and uranium should be analyzed in surface water.

Another question is whether there were increases in health problems after the Gold King Mine Spill. If so, an analysis could be done to find a possible correlation between the Gold King Mine Spill and a rise in health issues on the reservation.

Access to clean water is a basic human right. It is important for the health and safety of the residents that further studies are done and action is taken to help the Diné.