---
kind: "section"
citation: "40 C.F.R. § 98.350"
title: "40"
number: "98.350"
heading: "Definition of source category."
url: "https://uscodex.org/cfr/40/98.350"
---

# §98.350. Definition of source category.

- (a) This source category consists of anaerobic processes used to treat industrial wastewater and industrial wastewater treatment sludge at facilities that perform the operations listed in this paragraph.
  - (1) **Pulp and paper manufacturing.**
  - (2) **Food processing.**
  - (3) **Ethanol production.**
  - (4) **Petroleum refining.**
- (b) An anaerobic process is a procedure in which organic matter in wastewater, wastewater treatment sludge, or other material is degraded by micro-organisms in the absence of oxygen, resulting in the generation of CO2 and CH4. This source category consists of the following: anaerobic reactors, anaerobic lagoons, anaerobic sludge digesters, and biogas destruction devices (for example, burners, boilers, turbines, flares, or other devices).
  - (1) An anaerobic reactor is an enclosed vessel used for anaerobic wastewater treatment (e.g., upflow anaerobic sludge blanket, fixed film).
  - (2) Ananaerobic sludge digester is an enclosed vessel in which wastewater treatment sludge is degraded anaerobically.
  - (3) Ananaerobic lagoon is a lined or unlined earthen basin used for wastewater treatment, in which oxygen is absent throughout the depth of the basin, except for a shallow surface zone. Anaerobic lagoons are not equipped with surface aerators. Anaerobic lagoons are classified as deep (depth more than 2 meters) or shallow (depth less than 2 meters).
- (c) This source category does not include municipal wastewater treatment plants or separate treatment of sanitary wastewater at industrial sites.

## Notes

### Amendments

[75 FR 39767, July 12, 2010, as amended at 76 FR 73903, Nov. 29, 2011]

### Source

Source: 75 FR 39767, July 12, 2010, unless otherwise noted.

### Authority

Authority: 42 U.S.C. 7401-7671q.

### Source

Source: 74 FR 56374, Oct. 30, 2009, unless otherwise noted.

### Amendments

[75 FR 39767, July 12, 2010, as amended at 76 FR 73903, Nov. 29, 2011]