Tennessee Wastewater Operator Practice Exam

What is the fecal coliform pathogen limit for class B biosolids before they can be land applied according to 40 lbs part 503?

1. 1,000,000 CFU per gram

2. 2,000,000 CFU per gram

3. 10,000,000 CFU per gram

4. 500,000 CFU per gram

The correct answer is: 2,000,000 CFU per gram

The fecal coliform pathogen limit for Class B biosolids, as set by the standards outlined in the 40 CFR Part 503 regulations, specifies that the content must not exceed 2,000,000 CFU (colony-forming units) per gram on a dry weight basis before they can be safely land applied. This standard is put in place to ensure the treatment and management of biosolids minimizes health risks to humans and the environment. The regulations are designed to manage pathogens in biosolids effectively, and the specified limit is derived from epidemiological studies that assess the potential for disease transmission through the land application of treated wastewater solids. Thus, adhering to this limit is crucial for maintaining public health safety and environmental quality when utilizing biosolids in agricultural practices or soil amendment.