Figure: 30 TAC §290.111(d)(1)
| Pretreatment Provided | Filter Technology Used | |||
|---|---|---|---|---|
| Conventional Filters1 |
Membrane Filters and Cartridge Filters2 |
|||
| Giardia | Virus | Giardia3 | Virus | |
| No coagulation | NA4 | NA4 | 0.0-log | 4.0-log |
| Coagulation and flocculation | 1.0-log | 3.0-log | 0.0-log | 3.0-log |
| Coagulation, flocculation, and clarification |
0.5-log | 2.0-log | 0.0-log | 2.0-log |
1Filters in which water passes through a porous granular media and which utilize depth filtration processes.
2Filters in which particulate matter larger than 1 micrometer is rejected by an engineered barrier, primarily through a size-exclusion mechanism.
3The executive director will determine the required Giardia inactivation on a case-by-case basis.
4NA = Not Allowed. Conventional filtration with no coagulation is not allowed to receive Giardia or viral treatment credit.