How can septic system installation affect local groundwater?

The correct choice highlights an important aspect of septic system installation. Septic systems are designed to treat wastewater and release treated effluent into the soil. However, if not installed correctly or maintained properly, they can fail to function as intended. This failure can lead to the leaching of contaminants such as pathogens, nutrients, and chemicals into the surrounding soil and groundwater.

Contamination of local groundwater is a significant concern because this water source is often used for drinking and irrigation purposes. If harmful substances penetrate the groundwater, they can pose serious health risks to humans and animals, as well as negatively impact local ecosystems. As such, understanding the potential for septic systems to contribute to groundwater contamination is vital for both environmental sustainability and public health.

On the other hand, the other choices do not accurately represent the primary impact of septic system installation on groundwater. While improved irrigation options, enhanced water quality, and increased property values may occur due to proper septic maintenance or the availability of waste treatment systems, they do not directly relate to the negative effects septic systems can have on groundwater if not properly managed.