Page 43 - Water and Wastewater Engineering Design Principles and Practice

Power source No Yes No No No No No No No

III Not applicable
EPA Construction Grants Program guidance for minimum equipment and process reliability for the liquid-processing train
Treatment system Two minimum a No backup Single unit permissible Two minimum c Same as class I Two minimum a Same as class II Same as class II Same as class II Same as class II

Power source Not applicable No Optional Optional Optional Optional Optional Optional Optional Yes

Reliability classification II Treatment system Same as class I Same as class I Same as class I Same as class I I Same as class Multiple units a No backup No backup No backup Multiple units a

Power source Optional Yes Yes Yes Yes Yes Optional Optional Optional Yes c Remaining capacity with largest unit out of service must be able to achieve design maximum oxygen transfer; backup unit need not be installed.

I Adequate capacity for all flows
Treatment system Multiple units a Multiple units b Two minimum w/equal volume Multiple units c Multiple sections d Multiple units b Two minimum or backup e Multiple units b Two minimum Multiple units b a Remaining capacity with largest unit out of service must be for at least 50% of the design maximum flow. b Remaining capacity with largest unit out of service must be for at least 75% of the design ma

Component Primary sedimentation Blowers or mechanical Final sedimentation Chemical flash mixer Chemical sedimentation Disinfection basins Source: U.S. EPA, 1974.

TABLE 1-4 Holding basin Degritting Trickling filters Aeration basins aerators Diffusers Flocculation

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