AngloGold Ashanti is committed to prioritizing responsible water management and to the protection of local and regional water resources.
The topic of water is important globally, but even more critical in the arid southwestern United States and similar environments. The proposed North Bullfrog Project intersects the Oasis Valley and Sarcobatus Flat Basins. These sparsely populated basins are located in southern Nye County, Nevada.
The Sarcobatus Flat Basin is characterized by the southern limits of the Tonopah Basin ecosystem, whereas the Oasis Valley Basin begins the northern limits of the Mojave Basin and Range ecosystem. The two basins are composed of alluvial fans, volcanic formations, hills, and low mountains that rise above the basin floors of the Mojave Desert (~3,000 feet) to an average elevation of ~6,000 feet. The sparsely vegetated soils are erodible during storm events. In areas transitional to the Great Basin in the north, blackbrush dominates slopes just above the upper elevational limit for creosote bush. Elsewhere, a mixture of more typical Mojave Desert forbs, shrubs, and succulent species occurs, including Joshua tree, other yucca species, and cacti on rocky sites. In Sarcobatus Flat, stormwater runoff flows to the central playa. Depth to groundwater ranges from 20-feet below the surface in the playa to 100- to 200-feet on the margins of the basin and the adjacent alluvial fans.
Groundwater-dependent ecosystems (GDE) occur near but outside of the proposed project and will be continually monitored to ensure protection for these areas. These ecosystems are supported by groundwater; where this water meets the surface, abundant habitat is created for plant and animal communities. Animals (including humans) rely on groundwater, whether from river baseflow supported by alluvial, volcanic, or carbonate aquifers or at spring discharge locations, as a source of drinking water, particularly in the southwestern United States.
Additionally, the Amargosa River intermittently flows through parts of southern Nevada, including to the east of the proposed project. The Amargosa River is unique in that it flows underground for most of its length. Where the river emerges naturally to the surface or where it is sustained by a nearby perennial spring flow, it creates oases of habitats for aquatic species and supplies drinking water for terrestrial species. Though the Amargosa River does not intersect the Mine Plan of Operations, it is important that AngloGold Ashanti conducts studies to better understand and protect ground and surface water hydrology and biological resources in these important aquatic habitats.
Water resources management
AngloGold Ashanti is committed to environmental stewardship and is developing a mine plan for the proposed North Bullfrog Project that aims to minimize water use for the protection of groundwater-dependent ecosystems. The plan focuses on reducing water consumption and implementing best practices for managing water resources throughout the life of the mine and into closure. Before mining begins, AngloGold Ashanti is conducting rigorous water studies to identify and address potential dewatering and consumption-related impacts. A key focus of the studies is to understand both the local hydrogeological conditions and the local ecosystem to minimize potential impacts in coordination with local, state, and federal agencies.
Through thorough baseline studies, monitoring, and advanced mining procedures, AngloGold Ashanti’s proposed Nevada Projects can successfully protect local and regional water resources while generating value for the community.
Water resources monitoring
AngloGold Ashanti’s commitment to data collection includes multi-disciplinary baseline studies that began in 2021 and will continue through operation and closure. As a part of the Integrated Monitoring Plan, AngloGold Ashanti is required by the U.S. Bureau of Land Management (BLM), the Nevada Division of Water Resources (NDWR), and the Nevada Division of Environmental Protection (NDEP) to conduct ongoing monitoring to evaluate groundwater and surface water conditions, water quality and quantity data, and potential impacts to domestic wells, wildlife and the environment (See Seeps and springs monitoring under Biological resources). Groundwater sampling would be conducted using NDEP and U.S. Environmental Protection Agency-approved sampling methodologies.
The monitoring program will collect data from groundwater, surface water, and spring discharge sources as part of the baseline program. Climate data are also collected to assess the short- and long-term temperature and precipitation conditions (as well as other parameters). This gives AngloGold Ashanti the data to understand crucial issues such as drought patterns and to capture the details of intense desert storm events.
Data collection sources include AngloGold Ashanti-installed monitor and water supply wells, existing USGS and Nye County monitor wells, domestic wells, springs and seeps, weather stations, and other sources. The types of data collected, submitted, and reported will include water quality laboratory parameters including major, minor and trace elements, water level data, water quantity or flows, biological parameters, and weather data measurements. Other site-specific studies of water resources will include isotopic data collection and analysis.
Data reporting will align with the project permits and authorizations and will be submitted regularly to the NDEP, BLM, NDWR, and other governing agencies.