3,000 GALLON PER DAY OR LESS NO-DISCHARGE PERMIT EXEMPTION FOR DOMESTIC WASTEWATER DESIGN GUIDANCE

Water Protection Program fact sheet
03/2019
Division of Environmental Quality Director: Ed Galbraith
PUB1319

Some small, no-discharge, domestic wastewater treatment facilities can be eligible for a permit exemption and therefore not require Missouri Department of Natural Resources (department) approval. The exemption is applicable for facilities that:

At no time may the wastewater be discharged from the operating location (property) or to surface or groundwater.

The purpose of this publication is to help you understand what is needed to satisfy the 3,000 gallons per day or less no-discharge lagoon exemption. As described in Chapter 644.051, in order to meet or exceed the requirements of the exemption all no-discharge lagoons and any soil based treatment systems are required to be designed in accordance with 10 CSR 20-8.200 Wastewater Treatment Lagoons and Wastewater Irrigation Alternatives by a professional engineer registered in Missouri.

As described in 10 CSR 20-6.015 (2)(B), nothing shall prevent the department from taking action to ensure facilities do not discharge into surface or groundwater, including requiring construction or operating permits for facilities that were previously exempt. The department may require permits to correct noncompliance, or when construction or operation and maintenance practices are not adequate.

The no-discharge permit exemption does not excuse any facility or person from complying with the Missouri Clean Water Law or any other state or local laws. The burden of proof for the exemption is on the owner of the wastewater treatment system and it is their responsibility to demonstrate to the department that the system is and should be exempt from permitting requirements.

What is a “no-discharge” wastewater system?
For the purpose of this publication, a no-discharge wastewater system is one that is designed, constructed, operated and maintained to hold or irrigate/disperse domestic wastewater without discharging to surface or groundwater.

As defined in 10 CSR 20-2.010(50) Definitions, “No-discharge,” is a facility designed, constructed, and operated to hold or irrigate, or otherwise dispose without discharge to surface or subsurface waters of the state, all process wastes and associated stormwater flows except for discharges that are caused by catastrophic and chronic storm events; any basin is sealed in accordance with 10 CSR 20-8, Minimum Design Standards; and no subsurface releases exist in violation of 10 CSR 20-7.015, Effluent Regulations, or section 577.155, RSMo.

What is the definition of domestic wastewater?
As defined in 10 CSR 20-2.010(26) Definitions, “Domestic wastewater” is, wastewater (i.e., human sewage) originating primarily from the sanitary conveniences of residences, commercial buildings, factories, and institutions, including any water which may have infiltrated the sewers. Domestic wastewater excludes stormwater, animal waste, process waste, and other similar waste.

For the purpose of this publication “wastewater” or “domestic wastewater” shall be defined the same as “sewage” or “domestic sewage.”

When is an exemption possible?
An exemption from a construction or operating permit may be possible when a facility generates 3,000 gallons per day or less of domestic wastewater that is held within a no-discharge lagoon (earthen basin), followed by on-site surface land application, subsurface soil dispersal or is pumped and hauled to a permitted facility so that no discharges occur.

Who has regulatory jurisdiction over no-discharge lagoons?
No-discharge lagoons that serve anything other than a single family residence are the jurisdictional responsibility of the department throughout its life span.

When does a no-discharge lagoon not require construction or operating permits and when do they?
All 3,000 gallon per day or less no-discharge lagoons followed by surface land application, subsurface soil dispersal or is pumped and hauled to a permitted facility may be considered exempt by rule and would not be required to receive construction or operating permits.

As described in 644.051 RSMo, regardless if a construction permit is required the no-discharge lagoon, surface land application system or the subsurface soil dispersal system is required to be design by a registered professional engineer in accordance with 10 CSR 20-8, Minimum Design Standards. While not required it is highly recommended that you retain the wastewater treatment system design and have it available for review if needed.

As described in 10 CSR 20-6.015 (2)(B), if the department determines that construction or operation or maintenance practices of the wastewater system is not adequate, permits can be required to ensure the facility is protective of the public health and the environment.

Construction permits from the department are required for any no-discharge lagoon when the accumulated maximum daily flows of domestic wastewater operated under the same common promotional plan or operating location is greater than 3,000 gallons per day. An operating permit is required when those lagoons are followed by either surface land application or a subsurface soil dispersal system. However, an operating permit is not required when the wastewater from them is pumped and hauled to a permitted treatment or disposal facility, if the owner has a written contract with the hauler and approval from the receiving facility. For more information reagarding this exemption, please refer to the department publication Pump and Haul Operating Permit Exemption, PUB2658.

As described in 19 CSR 20-3.060(6)(D) , a single family lagoon serving no more than a single family residence is the jurisdictional responsibility of the Missouri Department of Health and Senior Services Onsite Wastewater Treatment Program or the local on-site wastewater authority (commonly the local health department) and does not qualify for the no-discharge lagoon exemption. The department recommends contacting the Missouri Department of Health and Senior Services Onsite Wastewater Treatment Program or the local on-site wastewater authority for specific design and permitting requirements.

No-discharge Lagoon
When designing a no-discharge lagoon the registered professional engineer will need to calculate the maximum amount of domestic wastewater expected to be produced per day to ensure there is sufficient storage volume in it to store the wastewater when the soil is frozen or snow covered during winter or during extended periods of saturated soil conditions. They will calculate the maximum daily design flows of domestic wastewater expected in accordance with 10 CSR 20-8, Minimum Design Standards or they can use accurate and verifiable waster use records if available. Accurate water use records will need to show the maximum daily flows while the time the facility is in use. Averages should not be used unless weighted against design flows as described in 10 CSR 20-8.200 Wastewater Treatment Lagoons and Wastewater Irrigation Alternatives.

Land Application
Regardless, if the registered professional engineer designs a surface land application system or a subsurface soil dispersal system it must be designed to handle lagoon effluent in such a manner that there is no discharge to surface or groundwater.

Typical types of surface irrigation systems used for domestic wastewater include portable pump(s) with movable sprinklers, pump(s) with solid-set sprinklers, or pump and gated pipe (fixed or movable) for overland flow. Domestic wastewater should only be surface land applied when the soils allow and not when the ground is frozen, snow covered or saturated.

Typical subsurface soil dispersal systems include conventional gravity-pipe and gravel systems, conventional gravity-gravelless pipe systems, low pressure pipe (LPP) systems, or drip irrigation systems.

The department recommends if the facility accumulated maximum daily flows of domestic wastewater for the entire facility under the same common promotional plan or operating location is less than or equal to 3,000 gallons per day and they propose to use a subsurface soil dispersal system following the no-discharge lagoon they should consider closing the lagoon and contacting the Missouri Department of Health and Senior Services Onsite Wastewater Treatment Program or the local on-site wastewater authority for specific design and permitting requirements for an on-site wastewater treatment system under their jurisdiction.

Summary
If a no-discharge lagoon has flows of domestic wastewater of 3,000 gallons per day or less and followed by either a surface land application system, a subsurface soil dispersal system or is pumped and hauled to a permitted facility, it may be considered exempt by rule and would not be required to receive a construction or operating permit. It is the facility owner’s responsibility to demonstrate to the department that the system is and should be exempt.

As described in 644.051 RSMo, regardless if a construction permit is needed all no-discharge lagoons, surface land application systems or subsurface soil dispersal systems are required to be design by a registered professional engineer and in accordance with 10 CSR 20-8.200 Wastewater Treatment Lagoons and Wastewater Irrigation Alternatives.

As described in 10 CSR 20-6.015 (2)(B), nothing shall prevent the department from taking action to ensure that facilities do not discharge into surface or groundwater, including requiring permits for facilities that were previously exempt and may require permits to correct noncompliance, or when it is determined that construction or operation and maintenance practices are not adequate, or for the protection of public health and the environment.

The no-discharge permit exemption does not excuse any facility or any person from complying with or from liability for violations of the Missouri Clean Water Law and regulations or any other state or local laws. Failure to operate and maintain the facility as a no-discharge wastewater treatment system may be considered a violation of the Missouri Clean Water Law and its regulations resulting in enforcement action.

While not required it is highly recommended that you retain the wastewater treatment system design and have it available for review if needed.

Accurate water use records will need to show the maximum daily flows while the time the facility is in use. Averages should not be used unless weighted against design flows as described in 10 CSR 20-8.200 Wastewater Treatment Lagoons and Wastewater Irrigation Alternatives.