Arizona: PFAS Contamination Fears Mount Over South32 Hermosa Mine

• Environmental advocates in Arizona's border region are concerned about a new South32 Hermosa mine exacerbating existing PFAS contamination in the Nogales Wash.
• The Hermosa mine, approved under fast-track "critical mining" rules, plans to extract zinc and manganese, raising fears of arsenic release and a "disease cluster."
• The Center for Biological Diversity has sued federal regulators under the Endangered Species Act, while Arizona Attorney General Kris Mayes is considering legal action over public nuisance and health threats.
• Mayes has called for an independent examination of the mine's impacts, noting the Arizona Department of Environmental Quality lacks funding for comprehensive PFAS review.
• South32 has funded its own health impact assessment and its president denied downstream metal flow, but community groups like the Calabasas Alliance continue to monitor and oppose the project.

Arizona Attorney General Kris Mayes has indicated her office is actively exploring legal avenues, characterizing the situation as both a public nuisance and a direct threat to public health and safety.

In Arizona's border region, environmental advocates are raising alarms over potential exacerbation of existing pollution challenges. The Nogales Wash, a nine-mile channel traversing the U.S.-Mexico border, currently transports storm runoff and wastewater from American-owned factories situated south of the border. This waterway, which carries its contents towards the Santa Cruz River, is notably contaminated with perfluoroalkyl and polyfluoroalkyl substances, commonly known as PFAS or "forever chemicals," alongside visible refuse and sewage. Robin Lucky, a local activist, has vividly described the Nogales Wash as the "unflushed toilet of Santa Cruz County," citing its pervasive odor and the presence of mosquitoes.

These "forever chemicals" pose a significant public health risk, contributing to conditions such as cancers, autoimmune diseases, and hormonal disruptions, primarily because they do not naturally degrade in the environment. PFAS are alarmingly prevalent, detected in the bloodstream of nearly every individual globally and in 83% of tested waterways across the United States. Their concentrations are particularly high around specific industrial and governmental sites, including airports, military installations, and mining operations—all of which are abundant in Arizona. Despite these known dangers, regulatory efforts to control PFAS have been limited, with past administrations, such as President Donald Trump's, even seeking to relax existing rules. This backdrop of widespread contamination and regulatory leniency fuels local concerns that new industrial developments could further compromise environmental and public health.

A focal point of these environmental anxieties is the proposed South32 Hermosa mine, located near Patagonia, Arizona. This project garnered federal approval under novel fast-track "critical mining" regulations, marking it as the first such endeavor to receive expedited clearance. The mine is slated for the extraction of heavy metals, specifically zinc and manganese, which are known to be hazardous. Critics, including Robin Lucky from the Calabasas Alliance, express serious apprehension that the drilling operations could inadvertently release arsenic, a highly toxic element, into the environment.

The connection between mining activities and PFAS pollution is a significant concern for local groups. Lucky has voiced fears that without stringent monitoring, the mine's operations could precipitate "another disease cluster" in the region. The expedited permitting process, which commenced in 2023, has been a continuous source of alarm for the Calabasas Alliance, an all-volunteer organization dedicated to environmental advocacy. The potential for heavy metals to migrate downstream through Patagonia and eventually into the Santa Cruz River is a primary worry for those opposing the project.

The concerns surrounding the South32 Hermosa mine and its potential environmental impact have attracted significant legal and governmental scrutiny. The Center for Biological Diversity has already initiated legal proceedings against federal regulators, asserting violations of the Endangered Species Act. Concurrently, Arizona Attorney General Kris Mayes has indicated her office is actively exploring legal avenues, characterizing the situation as both a public nuisance and a direct threat to public health and safety. Mayes emphasized her commitment to finding "any way that we can address this" in an October statement.

Attorney General Mayes has specifically called for a thorough and independent examination of the mine's potential effects. While the Arizona Department of Environmental Quality (ADEQ) currently conducts PFAS monitoring statewide, Mayes points out that the agency lacks sufficient funding to undertake a comprehensive review of the issue. She expressed optimism that a future legislature, particularly one controlled by Democrats, would adequately fund ADEQ, enabling it to perform the necessary independent studies. This statement was made just days before Democrats achieved control of both state chambers for the first time in six decades, a development that has paved the way for increased environmental oversight.

Despite the mounting opposition and legal challenges, South32 has remained publicly silent on the specific concerns raised by environmental groups and state officials, declining to comment for the original report. The company, which anticipates commencing operations in late 2027, has funded a health impact assessment through the University of Arizona. However, critics harbor doubts regarding the study's capacity to fully encompass the breadth of environmental and health risks associated with the project.

At a Santa Cruz County Board of Supervisors meeting in July, South32 President Pat Risner addressed some of these concerns. He asserted that arsenic levels were showing a downward trend and attributed a high test result for another toxic metal to a laboratory error, basing these claims on the company's own testing data. Risner also explicitly refuted the possibility that metals from the mine could flow downstream, passing through the town of Patagonia and ultimately reaching the Santa Cruz River. Robin Lucky, leading the Calabasas Alliance, has been a vocal opponent since the expedited permitting process for the Hermosa mine began in 2023, with her organization diligently collecting data on local air and water quality to support their advocacy.

Lawyers advising mining companies or environmental compliance officers in Arizona should note the heightened legal and activist scrutiny surrounding fast-tracked mining permits and potential PFAS contamination, indicating increased litigation risk and the need for robust environmental impact assessments and community engagement strategies.

Source: Original reporting via Courthouse News Service