The name asbestos is used to describe a variety of fibrous minerals, including chrysotile and crocidolite, which occur naturally as bundles of fibers that can be separated into durable filaments. The fibers are non-conductive and naturally resistant to chemicals and heat. During the early twentieth century, asbestos was commonly mined for its numerous industrial applications such as weather insulation and fireproofing for buildings. However, when asbestos-laden dust is inhaled, the microscopic mineral fibers are capable of piercing and damaging the cells in which they come into contact. This can cause lung irritation and lead to serious health problems, including cancer.

While many people worry about the asbestos insulation hazards found in older buildings, few consider the hazards associated with the minerals’ natural occurrence. Natural asbestos sources can be found throughout the Southwest, and it has been mined in both Utah and Arizona (Figure 9.23), though these mines are no longer in operation thanks to recent limitations placed on the minerals’ use. Remediation attempts on abandoned mines include blocking off access to contaminated areas and burying contaminated soil that has been found near surface water sources.

Figure 9.23: Presence of significant asbestos sources and former mines in the Southwestern states.

Natural events such as landslides can release previously trapped asbestos minerals, which can then be transported across great distances by the wind or even carried by surface water running over an asbestos site. Asbestos crystals can then make their way into streams and lakes, spreading contamination over large areas. People within the vicinity of exposed sources are at risk from windblown particles and mud particles collected on their shoes, clothing, and vehicles. The particles can then be carried into homes.