U.S. Nuclear Regulatory Commission
Question 39: Can biological material be defined better in
20.2003? For example, is all organic material biological
material? Can animal fats be released to the sewer?
Answer: Biological material, in its ordinary meaning, is
material pertaining to living organisms (plants or
animals). The statement of considerations indicates that
ground-up animal carcasses are examples of such material.
Animal fats are biological material and, if "dispersible,"
can be released to the sewer. (Reference: 10 CFR 20.2003