What type of mining activity can contaminate water supplies?

Mining activities, in general, can lead to the contamination of water supplies due to multiple factors involved in the extraction and processing of minerals. This process often involves the use of harsh chemicals, heavy machinery, and the disturbance of soil and rock layers, which can release pollutants into nearby water sources.

When mining operations expose minerals to air and water, it can initiate chemical reactions that produce toxic leachates, such as heavy metals and acidic runoff. These contaminants can seep into groundwater or flow into surface waters, significantly impacting the quality and safety of water supplies. This is particularly concerning in areas adjacent to mining operations where the potential for contamination is high.

Other activities listed, such as quarrying, sand mining, and recycling, may pose risks to water supplies, but mining—encompassing various types and methods generally has a broader scope and a greater potential for significant water contamination due to the nature of the materials being extracted and the scale at which they operate. Thus, the term "mining" captures the essence of the widespread environmental repercussions linked to this industry, making it the correct choice.