Tennessee Wastewater Operator Practice Exam

What is the minimum volatile solids (VS) reduction required to comply with the VAR under the 503 regulation?

1. 25%

2. 38%

3. 50%

4. 60%

The correct answer is: 38%

To comply with the Volatile Solids Reduction (VAR) as part of the 503 regulation, a minimum reduction of 38% in volatile solids is mandated. This regulation is significant as it aims to manage the treatment processes for sewage sludge, ensuring that the resulting biosolids are safe for land application. Achieving this 38% reduction indicates effective treatment processes like anaerobic digestion or other stabilization methods that reduce the organic content of the sludge, subsequently lowering the potential for odors and pathogens. A reduction of this magnitude ensures not only compliance with regulatory requirements but also contributes to environmental safety and sustainability practices in waste management. Understanding the context of the other options clarifies the importance of the specified threshold; a reduction of 25% would not meet regulatory expectations for land application, while 50% and 60% would exceed the minimum requirement, representing higher benchmarks of treatment efficacy but not necessary for compliance under the specified regulation. Thus, the focus remains on achieving the specific 38% reduction to ensure that regulatory standards are met.