Iowa Admin. Code r. 567-81.3

Current through Register Vol. 47, No. 11, December 11, 2024
Rule 567-81.3 - Wastewater treatment plant grades
(1)Classifications. The wastewater treatment plant classifications are listed in the following table:

Wastewater Treatment Plant Classifications

Treatment Type

Grade

Based on Design Pounds of BOD5/day

less than 334

334-835

836-2,505

2,506-8,350

more than 8,350

Based on Design Population Equivalent

less than 2,000

2,000-5,000

5,00115,000

15,00150,000

more than 50,000

1. Onsite Treatment System

W

Not

Applicable

Not

Applicable

Not

Applicable

Not

Applicable

2. Waste Stabilization Lagoon System

IL

IL

IL

IL

IL

3. Aerated Lagoon System

IL

IL

I

I

I

4. Advanced Aerated Lagoon System

II

II

II

II

II

5. Fixed Film Biological Treatment System

II

II

III

III

IV

6. Activated Sludge System

II

III

III

IV

IV

(2)Unknown design BOD5 loading. When the design BOD5loading is unknown, the plant BOD5loading shall be determined by using the average pounds of BOD5of the 24-hour composite influent samples taken in the last 12 months. If 24-hour composite influent samples are not available, then grab samples shall be used.
(3)IL wastewater operator requirements. A Grade I, II, III, or IV wastewater treatment certificate will satisfy the certification requirements for a Grade IL plant.
(4)Grade W onsite wastewater classification. Any wastewater treatment plant that discharges to a water of the state and that utilizes onsite wastewater treatment technologies, such as those specified in 567-Chapter 69, but excluding waste stabilization ponds, shall be classified as an onsite treatment system (Grade W).

Iowa Admin. Code r. 567-81.3

Amended by IAB February 9, 2022/Volume XLIV, Number 16, effective 3/16/2022