What qualifies as a Category 4 Sanitary Sewer Overflow (SSO)?

A Category 4 Sanitary Sewer Overflow (SSO) is defined by a spill that is considered minor in nature and is quantified as being less than 50 gallons. This classification helps to prioritize responses and reporting requirements based on the potential impact and severity of the overflow.

When an SSO is less than 50 gallons, it typically does not have a significant impact on the environment or public health compared to larger spills, making it categorized differently. Additionally, understanding these classifications is critical for proper reporting and environmental management practices.

Other categories of SSOs, such as those that impact surface water or involve larger volumes, would be classified differently due to their potential for greater environmental or health risks. Thus, determining the significance of the volume and context of the spill is essential in the classifications of sewer overflows.