Virginia Administrative Code
Title 9 - ENVIRONMENT
Agency 25 - STATE WATER CONTROL BOARD
Chapter 790 - SEWAGE COLLECTION AND TREATMENT REGULATIONS
Part III - Manual of Practice for Sewerage Systems and Treatment Works
Article 4 - Preliminary Processes
Section 9VAC25-790-520 - Pre-aeration
Current through Register Vol. 41, No. 3, September 23, 2024
Aeration of pretreated sewage should be provided whenever the low dissolved oxygen, or anaerobic condition, of the sewage can interfere with downstream unit operation reliability. Pre-aeration may be used to prevent solids deposition problems in on-line or off-line equalization or storage basins.
1. Pre-aeration unit operations shall be designed so that removal from service will not interfere with normal downstream operation of the remainder of the treatment process.
2. Inlet and outlet devices shall be designed to ensure proper distribution and help prevent solids deposition, while minimizing any hydraulic short circuiting effects.
3. The aeration equipment shall be capable of obtaining both adequate mixing and self-cleaning velocities within the basin. Any of the types of equipment used for aeration of biological reactors may be utilized.
4. A satisfactory means of grit removal shall be provided for operation of pre-aeration basins.
Statutory Authority
§ 62.1-44.19 of the Code of Virginia.