* | The values represent effluent maximum annual averages. |
** | Site specific; see WAC 246-272B-06250(7). |
Conditions | Minimum Required Treatment Level |
Project Specific1 | HQE2 |
Vertical Separation of 2 to < 3 feet, design flow higher than 14,500 gpd | HQE |
Soil Type 1 | B |
Vertical Separation of 2 to < 3 feet, design flow 14,500 gpd or less | C |
Sewage that is not residential strength | E |
All sites not requiring B, C, E or HQE | STE |
Sites where nitrogen or phosphorus is identified as a contaminant of concern | N10, N20, or P3 |
Table 6 notes: | |
1. | As identified during the site review process. |
2. | HQE: High quality effluent; project specific standards are set case-by-case. Treatment Level HQE is required where Treatment Level B is inadequate, or may be chosen by the LOSS owner. |
3. | As required by the department, based on the environmental review. Nitrogen treatment higher than N10 may be required for some sites. Phosphorus or other treatment value will be project specific, determined in the environmental review or by local or state regulation. |