Alabama Wastewater Treatment Operator Certification
Alabama grades wastewater treatment plants (ADEM 335-10-1-.03) by a combination of process type and flow (MGD) — not a single skill ladder. This makes the classification table essential reading for any Alabama wastewater operator.
The Classification Table
| Grade | Process | Flow |
|---|---|---|
| I | Wastewater treatment lagoon | ALL sizes |
| II | Trickling filter/biological contactor | 0 – 0.999 MGD |
| II | Activated sludge | 0 – 0.999 MGD |
| III | Trickling filter/biological contactor | 1.000 – 15.000 MGD |
| III | Activated sludge | 1.000 – 5.000 MGD |
| IV | Trickling filter/biological contactor | > 15.000 MGD |
| IV | Activated sludge | > 5.000 MGD |
Note the asymmetry: at Grade III, a trickling filter plant can be up to 15 MGD, while an activated sludge plant tops out at 5 MGD for t