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

Uses no oxygen

Answer

Requires a C:N ratio above 60:1

Answer

Produces no finished compost

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

RCRA Subtitle D

Answer

TSCA Section 8

Answer

CERCLA Section 107

Question 3

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

Accepted Answer

The solid/liquid residue remaining after digestion

Answer

The biogas produced

Answer

The pre-sorted feedstock

Answer

The enzyme used in the process

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

Coffee grounds

Answer

Fruit peels

Answer

Grass clippings

Question 5

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

Accepted Answer

50–60%

Answer

5–10%

Answer

20–30%

Answer

80–90%

Question 6

Anaerobic digestion of food waste primarily produces which two useful outputs?

Accepted Answer

Biogas and digestate

Answer

Compost and steam

Answer

Biochar and leachate

Answer

Syngas and ash