Nevada’s Abandoned Mine Lands: Challenges, Growth, and the Role of Broadbent & Associates, Inc.

By: Randy Miller, Principal Engineer and President

As Nevada’s population continues to surge, especially in cities like Las Vegas and Reno, the state is grappling with a growing housing crisis. To support continued growth, Nevada must develop new housing inventory, some of which may be on or near abandoned mine lands. These sites, relics of historical mining activities, carry a complex history and pose unique challenges. At the center of this effort to balance development, public safety, and environmental and historical preservation is Broadbent & Associates, Inc. (Broadbent), an environmental consulting firm deeply involved in assessing and mitigating hazards posed by abandoned mines.

The Historical Significance of Mine Sites

Mining has been a cornerstone of Nevada’s history since the mid-19th century. During the Gold Rush and the subsequent silver boom, Nevada’s underground riches drew thousands of miners, spurring economic growth and settlement in the region. By the early 20th century, Nevada had established itself as a mining powerhouse, contributing vital minerals to the national economy, particularly during key historical events. For example, Three Kids Mine, located just outside Las Vegas, was a significant source of manganese during World War II. These mines fueled the country's industrial expansion, but as mining practices evolved and commodity prices fluctuated, many sites were left abandoned.

A century ago, mining operations were far more primitive than the highly regulated and technologically advanced processes in use today. The focus was extraction of the target mineral(s); current agencies, laws, and regulations and sophisticated approaches, techniques, and permitting designed to prevent environmental impact did not exist. As a result, abandoned mine sites exist that can present hazards to modern communities that have since grown around them and can pose risks to health and safety for those recreating nearby or exploring these sites.

Environmental and Public Safety Hazards

Risks posed by abandoned mine lands are multifaceted, both physical and environmental hazards exist. Physically, abandoned sites can include dangerous terrain, unmarked shafts, tunnels, and unstable ground that can easily injure hikers, dirt bikers, or curious adventurers and their pets who stumble upon them. Such risks are compounded by the remoteness of many of these sites, making rescue operations difficult and slow in case of an accident.

Environmental hazards are equally concerning. When these mines were operational, the extraction processes left behind substances like arsenic, antimony, and lead. These metals exist in ore deposits together with target minerals such as gold, silver, and copper and can remain in soil and waste rock materials surrounding old mine sites. Ultimately, metals can be released into surface water through erosion or into the atmosphere through wind or human activity. Exposure to these can result in chronic health issues for residents living nearby if not properly mitigated. Other liquid or solid chemicals and materials used as blasting agents in the past can also exist. These can be dangerous and should only be handled by properly trained professionals if discovered. Harmful underground air conditions can also exist and can be damaging or even fatal to curious explorers if they decide to enter past underground mine workings.

Managing these hazards is imperative, not only for public safety but also for preserving Nevada's water resources. Contaminated runoff from mine lands can pollute streams, rivers, and lakes, exacerbating an already delicate water supply situation in a state that relies heavily on limited water sources.

Broadbent’s Role in Mitigating Hazards

To address these threats, Broadbent has taken a leading role in Nevada’s efforts to assess and remediate abandoned mine lands. Through partnerships with private industry and government agencies like the Bureau of Land Management (BLM), the U.S. Forest Service, the Nevada Division of Environmental Protection (NDEP), and the Nevada Division of Minerals (NDOM), Broadbent’s expertise is used to manage and mitigate hazards at sites across Nevada.

As an example, Broadbent collaborated with NDEP, NDOM, and the BLM to design and construct a passive treatment system to mitigate arsenic impacted water draining from an adit at an abandoned mine in northern Nevada. Passive treatment systems that don’t require a power source are effective at remote abandoned mine lands sites. Similarly, Broadbent is tasked with evaluating environmental risks at abandoned mines such as contamination of nearby water sources or the presence of toxic metals in the soil, under contract with NDEP. At the same time, the team must balance the need to preserve cultural and historical significance of these sites, ensuring that Nevada’s rich and diverse heritage is not lost in the process. Under an ongoing contract with NDOM, Broadbent archaeologists record historic mine sites and evaluate their historical significance so NDOM can work to mitigate physical hazards.

Legislative Challenges and Solutions

Environmental liability concerns have become a significant barrier to cleaning up abandoned mine lands. Industrial and mining companies, who would otherwise be interested in assessing and addressing hazards on abandoned sites located near their operations, are often deterred by the possibility of legal repercussions. Under current regulations, any company that voluntarily steps in to address contamination at an abandoned mine site can be held liable for environmental damage, even if it did not contribute to the original contamination. This legal framework deters private industry from participating in mine cleanup efforts.

However, there is a growing movement to change these laws. Industry leaders, government officials, and environmental advocates are pushing for legislative reforms to reduce liability for private companies that step in to help with remediation. In August 2024, the U.S. Senate passed the Good Samaritan Remediation of Abandoned Hardrock Mines Act of 2024 with unanimous consent. This bill is designed to address environmental damage caused by abandoned hardrock mines across the U.S. The Good Samaritan legislation would establish a new program under the Environmental Protection Agency (EPA) providing limited liability protections for up to 15 low-risk abandoned mine cleanup pilot projects conducted by state agencies, tribes, and qualified volunteer parties. This legislation, which now heads to the House of Representatives, could open the door for private industry to partner with government agencies in cleaning up and safely developing these sites.

The Growing Urgency and Call to Action

The widespread use of social media has brought new visibility to abandoned mine lands, with influencers and adventure seekers sharing videos of their explorations online. While this raises awareness, it also increases the risk of injury and the potential exposure to harmful substances. Managing these sites has become more critical as they gain visibility in the public eye.

As communities and industry in Nevada and other states continue to grow, managing the risks associated with abandoned mines will become increasingly important. Broadbent remains committed to advocating for sensible reforms that protect the public, encourage responsible development, and preserve the historical significance of abandoned mine lands. By working together with government agencies, private industry, and community stakeholders, Broadbent aims to ensure that future development is both safe and sustainable.