Rules & Regulations of the State of Tennessee
Title 0400 - Environment and Conservation
Subtitle 0400-40 - Water Resources (WPC)
Chapter 0400-40-05 - Individual National Pollutant Discharge Elimination System (NPDES) Permits
Section 0400-40-05-.09 - TECHNOLOGY-BASED EFFLUENT LIMITATIONS

Universal Citation: TN Comp Rules and Regs 0400-40-05-.09

Current through September 24, 2024

Permits shall impose the following technology-based effluent limitations, unless more stringent water quality-based effluent limitations are required for these pollutants:

(1) Municipal and domestic wastewater treatment plants shall be limited by application of monthly average concentrations, weekly average concentrations, daily maximum amounts, and daily maximum concentrations of the five day, 20°C biochemical or carbonaceous biochemical oxygen demand (BOD5 or CBOD5) and suspended solids. In some cases, the daily maximum amount may be replaced by a minimum daily percent removal requirement. Limitations on chlorine residual may be required to prevent harmful amounts of chlorine discharge to the receiving waters. In addition, where harmful materials are acquired in a collection system, effluent limitations applicable to the treatment system will be required for such parameters. The Commissioner may adjust these effluent limitations in accordance with 40 C.F.R. § 133.103(b) (2021).

(a) Conventional secondary treatment plants.

Parameter

Monthly Average (mg/l)

Weekly Average (mg/l)

Daily Maximum (mg/l)

Monthly Average % Removal

BOD5 or CBOD5

30/25

40/35

45/40

85

TSS

30

40

45

85

The concentration of settleable solids shall not exceed 1.0 ml/l as measured by the standard one-hour Imhoff cone test.

(b) Domestic waste stabilization lagoons.

Parameter

Monthly Average (mg/l)

Weekly Average (mg/l)

Daily Maximum (mg/l)

Monthly Average % Removal

BOD5/CBOD5

45/40

50/45

65/60

65

TSS

100

110

120

n/a

(2) Industrial discharges.

(a) For industrial discharges with applicable federal effluent limitations guidelines, technology-based effluent limitations and standards in accordance with those guidelines shall be applied.

(b) For industrial discharges without applicable federal effluent limitations guidelines, best professional judgment should be employed to establish appropriate effluent limitations and standards.

(c) A combination of the limitations derived from subparagraphs (2)(a) and (b) of this rule may be established in a permit, as applicable.

Authority: T.C.A. §§ 4-5-201, et seq. and 69-3-101, et seq.

Disclaimer: These regulations may not be the most recent version. Tennessee may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.