Jurisdictional Change of a Domestic Wastewater Facility
|Water Protection Program fact sheet||
|Division of Environmental Quality Acting Director: Steve Feeler||
With the implementation of more stringent discharge limits on domestic wastewater, the Department of Natural Resources has had a number of facilities proposing subsurface soil dispersal (absorption) systems to eliminate direct discharge and their National Pollutant Discharge Elimination System (NPDES) permit. Subsurface soil dispersal systems should be included among alternatives evaluated when changing the method of disposal from a direct discharging system. Facilities with flows 3,000 gallons per day (gpd) or less proposing to change to a subsurface soil dispersal system will be reviewed on a case-by-case basis, not only to determine if it is a sustainable solution, but if a change in jurisdiction from the Department of Natural Resources to the Department of Health and Senior Services, Onsite Wastewater Treatment Program or the local onsite wastewater administrative authority (commonly the local health department) is appropriate.
This fact sheet and checklist discuss subsurface soil dispersal systems and the basic documentation needed to help determine if using a subsurface soil dispersal system and changing jurisdiction is a viable option. This fact sheet is not intended to address specific design criteria nor is it meant to answer all of the “what if” questions. To better understand jurisdiction for domestic wastewater in the state it is recommended to review the Department of Natural Resources fact sheet titled Who Regulates Domestic Wastewater in Missouri – PUB 1296. As described within that fact sheet, the Department of Health and Senior Services Onsite Wastewater Treatment Program or the local onsite wastewater administrative authority have jurisdiction for facilities that generate 3,000 gallons per day or less of domestic wastewater and disperse effluent into a subsurface soil absorption system.
Domestic wastewater is defined in RSMo 701.025(12) as, “sewage” or “domestic sewage,” “Human excreta and wastewater, including bath and toilet waste, residential laundry waste, residential kitchen waste and other similar waste from household or establishment appurtenances.” For the purpose of jurisdiction anything not defined as domestic wastewater is considered industrial wastewater and is the Department of Natural Resources’ responsibility, regardless of the design flow.
Although, some consider a large-scale subsurface dispersal system nothing more than a “large septic system,” this is a misconception. For the purpose of this fact sheet the term “septic” will only be used as a component of a system, e.g. septic tank or anaerobic treatment.
Construction and operating permits from the Department of Natural Resources shall be required for all 3,000 gallons per day or less no-discharge lagoons when followed by subsurface soil dispersal system. This does not apply to a single-family lagoon serving an individual residence on an individual lot since they are the jurisdictional responsibility of the Missouri Department of Health and Senior Services, Onsite Wastewater Treatment Program or the local onsite wastewater administrative authority.
To better understand the 3,000 gallons per day or less no-discharge exemption, the Department of Natural Resources recommends reviewing the fact sheet 3,000 Gallons per Day or Less No-Discharge Domestic Wastewater Lagoon Exemption - PUB1319.
What is Subsurface Soil Dispersal?|
Subsurface soil dispersal is the method of distributing effluent uniformly into an unsaturated (vadose) zone within the soil allowing for the effective treatment and control of bacteria and nutrients along with the local reuse of the treated water.
Soil Treatment Area Requirements
In Missouri the minimum soil treatment area needed is based upon the soil and site conditions and their ability to treat and control the effluent effectively. This is determined only after a thorough systematic investigation of the soil properties and landscapes of the primary and reserve soil treatment areas.
The minimum square footage for a soil treatment area is calculated by dividing the daily wastewater flow by the soil application (loading) rate assigned by the onsite soil evaluator. Example: 3,000 gpd of domestic wastewater divided by an application rate of 0.20 gpd/sq. ft. equals 15,000 sq. ft. of soil treatment area. This calculation is for general discussion purposes only. Note the calculated area does not include area for the septic tanks, secondary treatment, pump tanks, trench separation, reserve area, set back distances, or other components of the wastewater collection and treatment system.
Operation and Maintenance
The primary challenge associated with any wastewater treatment system is that they are not always managed by individuals trained for a specific technology. Long-term operation and maintenance by qualified individuals is imperative to ensure all of the components, including the subsurface soil dispersal system functions optimally for the expected lifespan. Operation and maintenance must be addressed as part of the initial planning process and not as an afterthought.
Basic Documentation Needed for Review
The Department of Natural Resources and the Department of Health and Senior Services, Onsite Wastewater Treatment Program developed the attached checklist as a guide to compiling the minimum documentation needed for review. More documentation may be required depending upon the facility, soils, available area, geology, nature of use, etc. The majority of the information requested on the checklist should be on file with the owner or continuing authority as part of their records. To help keep this review cost effective, neither department is asking for a preliminary engineering report or a site specific design of the new system at this time.
Once the appropriate documentation is compiled copies should be sent to the Department of Health and Senior Services, Onsite Wastewater Treatment Program or the local onsite wastewater administrative authority for initial review and determination. If it is determined the use of a subsurface soil dispersal system is a feasible option and the change in jurisdictional authority is appropriate then the facility can begin to work with the appropriate permitting authority. If written approval for the change in the method of wastewater treatment is required from the Department of Natural Resources to satisfy the residential housing development rule, 10 CSR 20-6.030, it shall be received prior to the commencement of construction by any individual and before they apply for any approvals or permits as described within 19 CSR 20-3.060.
Once a facility receives the appropriate approvals and permits from the Department of Health and Senior Services, Onsite Wastewater Treatment Program or local onsite wastewater administrative authority construction may proceed. Once construction of the subsurface soil dispersal system and any other improvements to the wastewater treatment systems is completed the following shall be submitted to the Department of Natural Resources in order to complete the transition of jurisdiction.
- A copy of the approved construction final inspection form from the Department of Health and Senior Services, Onsite Wastewater Treatment Program or local administrative authority stating all design and construction activities are in compliance with 19 CSR 20-3.060 “Minimum Construction Standards for On-Site Sewage Disposal Systems” or any local ordinances.
- Form H – Request for Termination of a General Permit, MO 780-1409
- Form J – Request for Termination of a State Operating Permit, MO 780-1576
- A Class V Well Inventory Form for each active or new underground injection well (subsurface soil dispersal area), shall be submitted, to the Missouri Department of Natural Resources, Geological Survey Program, P.O. Box 250, Rolla, Missouri 65402.
The Department of Natural Resources, Department of Health and Senior Services - Onsite Wastewater Treatment Program and local onsite wastewater administrative authorities all recognize subsurface soil dispersal systems are a sustainable solution that is protective of the public health and the environment. Regardless of who has jurisdiction of a wastewater treatment facility all wastewater shall be in handled in such a manner that there is no violation of the Missouri Clean Water Law and its regulations.
Please contact the Department of Natural Resources at 800-361-4827 or the Department of Health and Senior Services, Onsite Wastewater Treatment Program at 866-628-9891 for more information.
To help the Missouri Department of Health and Senior Services determine if converting a point-discharge domestic wastewater treatment system to one with subsurface soil dispersal is a sustainable solution and if a change in jurisdiction (permitting authority) is necessary, please provide the following information to them. The majority of the information requested should be on file with the owner or continuing authority as part of their records. More information may be needed depending upon the complexity of the existing domestic wastewater treatment system, soils, landscape, geology, etc.
- Provide the current NPDES operating permit number and expiration date for the facility. If available a copy of the current operating permit should be included.
- Provide the name of the current owner or continuing authority of the facility and their mailing address.
- Provide the physical address, legal description and county where the facility is located.
- Provide copies of the Department of Natural Resources’ last inspection report.
- Provide copies of all discharge monitoring reports submitted to the Department of Natural Resources for the previous 12 months.
- If the facility is currently in violation of the Missouri Clean Water Law and its regulations, describe the violation and attach any documentation received from the Department of Natural Resources.
- Will changing the method of wastewater treatment to subsurface soil dispersal require written approval from the Department of Natural Resources per the criteria set-forth in 10 CSR 20-6.030 “Disposal of Wastewater in Residential Housing Developments”? Examples of developments required to receive written approval from the Department of Natural Resources for the method of wastewater treatment include but are not limited to:
- An existing subdivision with seven or more lots less than five acres or an expansion of three or more lots less than five acres,
- An existing recreational development with seven or more lots/camping sites or an expansion of three or more lots/camping sites,
- An existing multiple-family development with seven or more units or an expansion of three or more units.
If written approval is required from the Department of Natural Resources as described in the residential housing development rule, 10 CSR 20-6.030, it shall be received prior to the commencement of construction by any individual and before they apply for any onsite wastewater treatment system approvals or permits under 19 CSR 20-3.060 or local ordinances.
Daily Design Flow
- Provide the maximum daily design flow for domestic wastewater in gallons per day as stated in the NPDES permit.
- Calculate the estimated maximum daily domestic wastewater design flow in gallons per day using 19 CSR 20-3.060, Table 2A – Quantities of Domestic Sewage Flows.
- If available provide the actual water use records for review. Monthly metered water use records can be used, but daily verifiable water meter readings are preferred. The following is the minimum documentation that should be used as supporting documentation:
- Minimum of one year for year round use facilities,
- Minimum one full season water use records for seasonal establishments such as; Recreational Vehicle Campgrounds, Schools, Outdoor Theaters, Church Retreats, etc.,
- Description of water use patterns must be included:
- Days and hours open,
- High and low business days,
- Number of weeks per year or season,
- What season(s) is the facility opened,
- If available, provide copies of the original engineering plans for the current wastewater treatment system.
- Briefly describe the existing wastewater treatment systems components and design flow.
- Provide a copy of the operation and maintenance manual.
- List problems and noncompliance issues not previously discussed (attach documentation).
- If another wastewater collection and treatment system is available, provide the following information: approximate distance to the collection line and who is the continuing authority.
- Provide the owners names, if changing. For the purpose of this checklist the owner is defined as the individual or entity responsible for the continued operation and maintenance activities required to ensure the dependable function and financial responsibility of the collection and treatment system.
- Provide any and all documentation related to expected growth or change in the nature of use that will affect the maximum daily flow or the type of wastewater being treated e.g., increase in population for a school, expansion of a restaurant, expansion of residential housing units, change of business that would generate industrial waste, etc. For the purpose of this checklist industrial waste is anything not defined as domestic wastewater.
- List proposed pretreatment upgrades, modifications or replacement of existing components.
- Provide documentation of ownership where the soil treatment area is to be located.
- If available provide a copy of the detailed soil and site evaluation. If a detailed soil and site evaluation has not been conducted has one been scheduled?
- If known provide the amount of estimated soil treatment area needed as determined by the soil and site evaluation.
- Describe the proposed soil treatment/dispersal system.
- List variances that might be needed from the Department of Health and Senior Services, Onsite Wastewater Treatment Program or the local onsite wastewater administrative authority:
- Provide a copy of the soil map and legend from the Natural Resources Conservation Service, County Soil Survey with the boundary of the proposed soil treatment area clearly delineated. Copies of the published county soil surveys can be found at: www.nrcs.usda.gov/wps/portal/nrcs/surveylist/soils/survey/state/?stateId=MO
- Provide a copy of the U.S. Geological Survey Topography Map with the boundary of the soil treatment area clearly delineated. Copies of the USGA topographic maps can be found at: www.usgs.gov/pubprod/
- Provide any other pertinent information.
Submitting the items on this checklist does not obligate the Department of Natural Resources, the Department of Health and Senior Services’ Onsite Wastewater Treatment Program or the local onsite wastewater administrative authority to approve the use of any subsurface soil dispersal system.