Final answer:
All listed options.
Agricultural products, septic tanks, and radioactive disposal sites, are sources of groundwater contamination, affecting the quality and safety of water extracted from aquifers.
Step-by-step explanation:
Groundwater contamination is a significant environmental issue that affects the quality of water drawn from aquifers for various uses.
Sources of groundwater contamination can be numerous, including both human activities and natural processes. Some of the human-induced sources are agricultural runoff, leaching from septic tanks, and contamination from radioactive disposal sites.
Agricultural products, such as fertilizers and pesticides, often contain chemicals that can percolate through the soil and contaminate the groundwater.
Septic tank systems, if not properly maintained, can leak, allowing untreated sewage to seep into the groundwater. Similarly, radioactive disposal sites can be sources of hazardous waste penetration into the groundwater system.
It is important to understand the pathways through which contaminants travel, as groundwater generally flows from areas of higher elevation to lower elevation, spreading pollutants over wide areas and making containment challenging.
With about 20% of water used in the United States coming from groundwater, it's crucial to safeguard it from contamination to protect public health and the environment.