CLASS |  | FACILITY |  | DESIGN CAPACITY |
 |  |  |  |  |
I-C |  | Collection only (voluntary) |  | up to 1,000,000 GPD (1.0 MGD) |
 |  |  |  |  |
II-C |  | Collection only (voluntary) |  | greater than 1,000,000 GPD (1.0 MGD) |
 |  |  |  |  |
I |  | Waste Stabilization Lagoon |  | All |
 |  | Septic Tank-Sand |  |  |
 |  | Filter |  | All |
 |  |  |  |  |
II |  | Aerated Lagoon |  | All |
 |  | Trickling Filter |  | less than 300,000 GPD (0.3 MGD) |
 |  | Activated Sludge |  | less than 100,000 GPD (0.1 MGD) |
 |  |  |  |  |
III |  | Trickling Filter |  | 300,000 to 3,000,000 GPD (0.3 to 3.0 MGD) |
 |  | Activated Sludge |  | 100,000 to 2,000,000 GPD (0.1 to 2.0 MGD) |
 |  |  |  |  |
IV |  | Trickling Filter |  | greater than 3,000,000 GPD (3.0 MGD) |
 |  | Activated Sludge |  | greater than 2,000,000 GPD (2.0 MGD) |