Which type of pollution is typically harder to control due to its diffuse nature?

Non-point source pollution is typically harder to control due to its diffuse nature because it does not originate from a single, identifiable source. Instead, it comes from multiple sources and is often carried into water bodies through rainfall, snowmelt, or runoff. This means that pollutants can accumulate from a variety of land uses, such as agricultural practices, urban areas, and even natural landscapes, making it difficult to pinpoint and directly manage the sources of pollution.

In contrast, point source pollution is much easier to regulate because it comes from a specific, identifiable location, such as a pipe or a discharge point. Surface water pollution and groundwater pollution can also stem from both point and non-point sources, but they can be more readily managed if the pollution is coming from known discharge points rather than from widespread, unregulated runoff. The diffuse nature of non-point source pollution complicates monitoring, regulation, and remediation efforts, making it a significant challenge for environmental management.