Step 1 Required Removal of TOC by Enhanced Coagulation and Enhanced Softening for Subpart H Systems Using Conventional Treatment1 2
Source-water TOC, mg/L | Source-water alkalinity, mg/L as CaCO3 (in precentages) | ||
0-60 | [GREATER THAN]60-120 | [GREATER THAN]1203 | |
[GREATER THAN]2.0-4.0 | 35.0 | 25.0 | 15.0 |
[GREATER THAN]4.0-8.0 | 45.0 | 35.0 | 25.0 |
[GREATER THAN]8.0. | 50.0 | 40.0 | 30.0 |
1 Systems meeting at least one of the conditions in paragraph (a)(2)(i)-(vi) of this section are not required to operate with enhanced coagulation.
2 Softening system meeting one of the alternative compliance criteria in paragraph (a)(3) of this section are not required to operate with enhanced softening.
3 System practicing softening must meet the TOC removal requirements in this column.
Enhanced Coagulation Step 2 target pH
Alkalinity (mg/L as CaCO3) | Target pH |
0-60 | 5.5 |
[GREATER THAN]60-120 | 6.3 |
[GREATER THAN]120-240 | 7.0 |
[GREATER THAN]240 | 7.5 |
(1-(treated water TOC/source water TOC)) * 100
40 C.F.R. §141.135