How is odorous water generally classified that exceeds the Secondary MCL?

Water that exceeds the Secondary Maximum Contaminant Level (MCL) is primarily evaluated based on aesthetic criteria, which include taste, odor, and appearance. The Secondary MCLs are established by the Environmental Protection Agency (EPA) to address non-health-related concerns that affect the aesthetic quality of drinking water.

When water has an unpleasant odor, it is typically classified as "not aesthetically pleasing." This classification reflects the focus on sensory standards rather than safety measures. While odorous water might not be harmful from a health perspective, its unattractive smell can deter individuals from consuming it and can lead to dissatisfaction with water quality. Indicators like taste and odor largely influence consumer perception and acceptance of drinking water.

In contrast, classifications like safe for consumption or suitable for irrigation would imply that the water meets health and usability standards, which does not necessarily align with the presence of odor as defined by Secondary MCL evaluations. Similarly, classifying the water as highly toxic would misrepresent the nature of the concern, which is fundamentally about aesthetics rather than immediate health risks. Thus, "not aesthetically pleasing" most accurately captures the essence of what it means to exceed the Secondary MCL in terms of odor.