- a) Local land use.
- b) System energy requirements.
- c) Cost effectiveness of sludge thickening and dewatering.
- d) Equipment complexity and staffing requirements.
- e) Adverse effects of heavy metals and other sludge components upon the unit processes.
- f) Sludge digestion or stabilization requirements.
- g) Side stream or return flow treatment requirements (e.g., digester or sludge storage facilities supernatant, dewatering unit filtrate, wet oxidation return flows).
- h) Sludge storage requirements.
- i) Methods of ultimate disposal.
- j) Back-up techniques of sludge handling and disposal.
The selection of sludge handling unit processes should be based upon at least the following considerations:
(Source: Amended at 21 Ill. Reg. 12444, effective August 28, 1997)