CPWM CPWM Composting and Organic Waste Management Questions and Answers 2

Question 1

In-vessel composting differs from windrow composting primarily because it:

Accepted Answer

Occurs inside an enclosed, controlled container

Answer

In-vessel composting occurs in enclosed drums, tunnels, or reactors that allow precise control of temperature, moisture, and aeration.

Question 2

Which federal regulation governs land application of sewage sludge (biosolids) and sets limits for pathogens and heavy metals?

Accepted Answer

40 CFR Part 503

Answer

40 CFR Part 503 (EPA's 'biosolids rule') establishes standards for the use and disposal of sewage sludge, including pathogen reduction and pollutant limits.

Question 3

What does 'digestate' refer to in anaerobic digestion of organic waste?

Accepted Answer

The solid/liquid residue remaining after digestion

Answer

Digestate is the nutrient-rich solid and liquid material left after anaerobic microorganisms have broken down organic feedstock and captured biogas.

Question 4

Which of the following is a contaminant commonly found in source-separated organics that reduces compost quality?

Accepted Answer

Plastic film bags

Answer

Plastic film bags are a major contaminant in organics collection programs because they do not break down and leave microplastic residues in finished compost.

Question 5

What is the recommended moisture content range for an actively composting pile?

Accepted Answer

50–60%

Answer

Moisture content of 50–60% supports microbial activity without saturating the pile and causing anaerobic conditions.

(CPWM) Certified Professional in Waste Management Practice Test

(CPWM) Certified Professional in Waste Management Practice Test

CPWM CPWM Composting and Organic Waste Management Questions and Answers 2