Final answer:
Nitrates are the most common chemical contaminant in groundwater, often stemming from the runoff of fertilizers used in agriculture. They lead to issues such as eutrophication which affects water oxygen levels and aquatic life. Solutions include reducing fertilizer use and protecting wetlands.
Step-by-step explanation:
The chemicals used on farms, golf courses, and domestic gardens may contribute to groundwater contamination. The main chemical contaminant found in groundwater is nitrates, which, due to their stability in high oxygen conditions, do not degrade easily. This type of water pollution can be attributed to various sources, including agricultural activities, on-site sanitation, and sewage sludge disposal. Runoff from fertilizer application is a prevalent cause of nitrate pollution, leading to environmental concerns such as eutrophication, where excess nutrients foster excessive growth of algae that deplete the oxygen needed for other aquatic life.
Several measures can mitigate these issues, including reducing fertilizer use and preserving wetlands, which naturally filter runoff. Additionally, understanding that pollution can come from both point and nonpoint sources is crucial for the protection of water quality. Nonpoint sources are particularly challenging as pollutants such as herbicides, pesticides, and fertilizers are picked up by rainfall and carried into various water bodies.