Arizona Administrative Code
Title 18 - ENVIRONMENTAL QUALITY
Chapter 9 - DEPARTMENT OF ENVIRONMENTAL QUALITY - WATER POLLUTION CONTROL
Article 3 - AQUIFER PROTECTION PERMITS - GENERAL PERMITS
Part A - GENERAL PROVISIONS
Section R18-9-A309 - General Provisions for On-site Wastewater Treatment Facilities

Universal Citation: AZ Admin Code R 18-9-A309

Current through Register Vol. 30, No. 38, September 20, 2024

A. General requirements and prohibitions.

1. No person shall discharge sewage or wastewater that contains sewage from an on-site wastewater treatment facility except under an Aquifer Protection Permit issued by the Director.

2. A person shall not install, allow to be installed, or maintain a connection between any part of an on-site wastewater treatment facility and a drinking water system or supply so that sewage or wastewater contaminates the drinking water.

3. A person shall not bypass or release sewage or partially treated sewage that has not completed the treatment process from an on-site wastewater treatment facility.

4. A person shall not use a cesspool for sewage disposal.

5. A person constructing a new on-site wastewater treatment facility or replacing the treatment works or disposal works of an existing on-site wastewater treatment facility shall connect to a sewage collection system if either (a) or (b) below apply:
a. One of the following applies:
i. A provision of a Nitrogen Management Area designation under R18-9-A317(C) requires connection;

ii. A county, municipal, or sanitary district ordinance requires connection; or

iii. The on-site wastewater treatment facility is located within an area identified for connection to a sewage collection system by a Certified Area-wide Water Quality Management Plan adopted under 18 A.A.C. 5 or a master plan adopted by a majority of the elected officials of a board or council for a county, municipality, or sanitary district; or

b. A sewer service line extension is available at the property boundary and both of the following apply:
i. The service connection fee is not more than $6000 for a dwelling or $10 times the daily design flow in gallons for a source other than a dwelling, and

ii. The cost of constructing the building sewer from the wastewater source to the service connection is not more than $3000 for a dwelling or $5 times the daily design flow in gallons for a source other than a dwelling.

6. The Department shall prohibit installation of an on-site wastewater treatment facility if the installation will create an unsanitary condition or environmental nuisance or cause or contribute to a violation of an Aquifer Water Quality Standard.

7. A person shall design and operate the permitted on-site wastewater treatment facility so that:
a. Flows to the facility consist of typical sewage and do not include any motor oil, gasoline, paint, varnish, solvent, pesticide, fertilizer, or other material not generally associated with toilet flushing, food preparation, laundry, or personal hygiene;

b. Flows to the facility from commercial operations do not contain hazardous wastes as defined under A.R.S. § 49921(5) or hazardous substances;

c. If the sewage contains a component of nonresidential flow such as food preparation, laundry service, or other source, the sewage is adequately pretreated by an interceptor that complies with R18-9-A315 or another device authorized by a general permit or approved by the Department under R18-9-A312(G);

d. Except as provided in subsection (A)(7)(c), a sewage flow that does not meet the numerical levels for typical sewage is adequately pretreated to meet the numerical levels before entry into an on-site wastewater treatment facility authorized by this Article;

e. Flow to the facility does not exceed the design flow specified in the Discharge Authorization;

f. The facility does not create an unsanitary condition or environmental nuisance, or cause or contribute to a violation of either a Aquifer Water Quality Standard or a Surface Water Quality Standard; and

g. Activities at the site do not adversely affect the operation of the facility.

8. A person shall control the discharge of total nitrogen from an on-site wastewater treatment facility as follows:
a. For an on-site wastewater treatment facility operating under the 1.09 General Permit or proposed for construction in a Notice of Intent to Discharge under a Type 4 General Permit and the facility is located within a Nitrogen Management Area, the provisions of R18-9-A317(D) apply;

b. For an on-site wastewater treatment facility proposed for construction in a Notice of Intent to Discharge under R18-9-E323, the provisions of R18-9-E323(A)(4) apply;

c. For a subdivision proposed under 18 A.A.C. 5, Article 4, for which on-site wastewater treatment facilities are used for sewage disposal, the permittee shall demonstrate in the geological report required in R18-5-408(E)(1) that total nitrogen loading from the on-site wastewater treatment facilities to groundwater is controlled by providing one of the following:
i. For a subdivision platted for a single family dwelling on each lot, calculations that demonstrate that the number of lots within the subdivision does not exceed the number of acres contained within the boundaries of the subdivision;

ii. For a subdivision platted for dwellings that do not meet the criteria specified in subsection (A)(8)(c)(i), calculations that demonstrate that the nitrogen loading over the total area of the subdivision is not more than 0.088 pounds (39.9 grams) of total nitrogen per day per acre calculated at a horizontal plane immediately beneath the active treatment of the disposal fields, based on a total nitrogen contribution to raw sewage of 0.0333 pounds (15.0 grams) of total nitrogen per day per person; or

iii. An analysis by another means of demonstration showing that the nitrogen loading to the aquifer due to on-site waste-water treatment facilities within the subdivision does not cause or contribute to a violation of the Aquifer Water Quality Standard for nitrate at the applicable point of compliance.

9. Repairs and Routine Work.
a. A Notice of Intent to Discharge is not required for repair or routine work that maintains a facility.

b. A Notice of Intent to Discharge is required for the following non-routine work or repairs:
i. Converting a facility from operation under gravity to one requiring a pump or other mechanical device for treatment or disposal;

ii. Modifying or replacing a treatment works or disposal works, as defined in R18-9-101; or

iii. Modifying a facility in any manner that is inconsistent with the originally approved design and installation of the facility.

c. A permittee shall comply with any local ordinance that provides independent permitting requirements for repair or routine work.

d. A person, as defined in R18-9-101, shall not modify the facility so as to create an unsanitary condition or environmental nuisance or cause or contribute to an exceedance of a water quality standard.

10. Cumulative flows. When there is more than one on-site wastewater treatment facility on a property or on a site under common ownership or subject to a larger plan of sale or development, the Director shall determine whether an individual permit is required or whether the applicant qualifies for coverage to discharge under a general permit based on the sum of the design flows from the proposed installation and existing on-site wastewater treatment facilities on the property or site.
a. If the sum of the design flows is less than 3000 gallons per day, the Department will process the application under R18-9-E302 through R18-9-E322, as applicable.

b. If the sum of the design flows is equal to or more than 3000 gallons per day but less than 24,000 gallons per day, the Department will process the application under R18-9-E323.

c. If the sum of the design flows is equal to or more than 24,000 gallons per day, the project does not qualify for coverage under a Type 4 General Permit and the applicant shall submit an application for an individual permit under Article 2 of this Chapter.

11. The use of a gray water system does not change the design, capacity, or reserve area requirements for an on-site wastewater treatment facility regulated under R18-9-E302 through R18-9-E323. The design of an on-site facility shall ensure the on-site facility can treat and dispose of the combined black water and gray water flows generated at the site. Black water includes waste-water flows from a kitchen sink. Kitchen sink wastewater flows are not gray water. Kitchen sink wastewater flows are not gray water even if a holding tank receiving kitchen sink wastewater, such as a recreational vehicle holding tank, is labeled as holding gray water. Gray water, as defined in R18-9-101, may be utilized in accordance with Article 7 of this Chapter.

12. To obtain coverage under a Type 4 General Permit, an applicant must, in the following order:
a. Submit a Notice of Intent to Discharge according to requirements in R18-9-A301(B), R18-9-A309(B), and according to permit-specific requirements in Part E of Article 3,

b. Receive a Construction Authorization from the Director pursuant to R18-9-A301(D)(1)),

c. Submit a Request for Discharge Authorization according to requirements in R18-9-A301(D)(1)(f), R18-9-A309(C), and according to permit-specific requirements in Part E of Article 3, and

d. Receive a Discharge Authorization from the Director pursuant to R18-9-A301(D)(2) and R18-9-A309(C).

B. Notice of Intent to Discharge under a Type 4 General Permit. In addition to the Notice of Intent to Discharge requirements specified in R18-9-A301(B), an applicant shall submit the following information in a format approved by the Department:

1. A site investigation report that summarizes the results of the site investigation conducted under R18-9-A310(B), including:
a. Results from any soil evaluation, percolation test, or seepage pit performance test;

b. Any surface limiting condition identified in R18-9-A310(C)(2); and

c. Any subsurface limiting condition identified in R18-9-A310(D)(2);

2. A site plan that includes:
a. The parcel and lot number, if applicable, the property address or other appropriate legal description, the property size in acres, and the boundaries of the property;

b. A plan of the site drawn to scale, dimensioned, and with a north arrow that shows:
i. Proposed and existing on-site wastewater treatment facilities; dwellings and other buildings; driveways, swimming pools, tennis courts, wells, ponds, and any other paved, concrete, or water feature; down slopes and cut banks with a slope greater than 15 percent; retaining walls; and any other constructed feature that affects proper location, design, construction, or operation of the facility;

ii. Any feature less than 200 feet from the on-site wastewater treatment facility excavation and reserve area that constrains the location of the on-site wastewater treatment facility because of setback limitations specified in R18-9-A312(C);

iii. Topography, delineated with an appropriate contour interval, showing original and post-installation grades;

iv. Drainage patterns, and as applicable, drainage controls and erosion protection for the facility;

v. Location and identification of the treatment and disposal works and wastewater pipelines, the reserve disposal area, and location and identification of all sites of percolation testing and soil evaluation performed under R18-9-A310; and

vi. Location of any public sewer if 400 feet or less from the property line;

3. The design flow of the on-site wastewater treatment facility, consisting of gray water and black water flows, expressed in gallons per day based on Table 1, Unit Design Flows, the expected strength of the wastewater if the strength exceeds the levels for typical sewage, and:
a. For a single family dwelling, a list of the number of bedrooms and plumbing fixtures and corresponding unit flows used to calculate the design flow of the facility; and

b. For a dwelling other than for a single family, a list of each wastewater source and corresponding unit flows used to calculate the design flow of the facility;

4. A list of materials, components, and equipment for constructing the on-site wastewater treatment facility;

5. Drawings, reports, and other information that are clear, reproducible, and in a size and format specified by the Department;

6. If pretreatment is necessary for a facility to comply with the requirements of this Chapter, including R18-9-A309(A)(7), then a design report approved by the on-site wastewater treatment facility manufacturer or manufacturers that specifies component capacities, control settings, and supplemental installation and operation practices necessary to produce typical sewage numerical levels before entry into an on-site wastewater treatment facility; and

7. For a facility that includes treatment or disposal works permitted under R18-9-E303 through R18-9-E323:
a. Construction quality drawings that show the following:
i. Systems, subsystems, and key components, including manufacturer's name, model number, and associated construction notes and inspection milestones, as applicable;

ii. A title block, including facility owner, revision date, space for addition of the Department's application number, and page numbers;

iii. A plan and profile with the elevations of wastewater pipelines, and treatment and disposal components, including calculations justifying the absorption area, to allow Department verification of hydraulic and performance characteristics;

iv. Cross sections showing wastewater pipelines, construction details and elevations of treatment and disposal components, original and finished grades of the land surface, seasonal high water table if less than 10 feet below the bottom of a disposal works or 60 feet below the bottom of a seepage pit, and a soil elevation evaluation to allow Department verification of installation design and performance; and

b. A draft operation and maintenance manual for the on-site wastewater treatment facility consisting of the tasks and schedules for operating and maintaining performance over a 20-year operational life;

C. Additional requirements for a Request for Discharge Authorization and for the issuance of a Discharge Authorization under a Type 4 General Permit.

1. If the entire on-site wastewater treatment facility, including treatment works and disposal works, will be permitted under R18-9-E302, the Director shall issue the Discharge Authorization if, as a part of the Request for Discharge Authorization:
a. The site plan accurately reflects the final location and configuration of the components of the treatment and disposal works, and

b. The applicant or the applicant's agent certifies on the Request for Discharge Authorization form that the septic tank passed the watertightness test required by R18-9-A314(5)(d).

2. If the on-site wastewater treatment facility is proposed under R18-9-E303 through R18-9-E323, either separately or in any combination with each other or with R18-9-E302, the Director shall issue the Discharge Authorization if the following documents are submitted to the Department as part of the Request for Discharge Authorization:
a. As-built plans showing changes from construction quality drawings submitted under subsection (B)(6)(a);

b. A final list of equipment and materials showing changes from the list submitted under subsection (B)(4);

c. A final operation and maintenance manual for the on-site wastewater treatment facility consisting of the tasks and schedules for operating and maintaining performance over a 20-year operational life;

d. A certification that a service contract for ensuring that the facility is operated and maintained to meet the performance and other requirements of the applicable general permits exists for at least one year following the beginning of the operation of the on-site wastewater treatment facility, including the name of the service provider, if the on-site wastewater treatment facility is permitted under:
i. R18-9-E304;

ii. R18-9-E308 through R18-9-E315;

iii. R18-9-E316, if the facility includes a pump; or

iv. R18-9-E318 through R18-9-E322;

e. Other documents, if required by the separate general permits in 18 A.A.C. 9, Article 3, Part E;

f. A Certificate of Completion signed by the current engineer or designer of record assuring that installation of the facility conforms to the design approved under the Construction Authorization under R18-9-A301(D)(1)(c); and a regulatory representative, such as an inspector, may not act as an applicant's agent, nor authorize backfill before the current engineer or designer of record has verified proper installation of the system;

g. The name of the installation contractor and the Registrar of Contractor's license number issued to the installation contractor; and

h. A certification that any septic tank installed as a component of the on-site wastewater treatment facility passed the water-tightness test required by R18-9-A314(5)(d).

3. The Director shall specify in the Discharge Authorization:
a. The permitted design flow of the facility,

b. The characteristics of the wastewater sources contributing to the facility, and

c. A list of the documents submitted to and reviewed by the Department satisfying subsection (C)(2).

D. Closure requirements. A person who permanently discontinues use of an on-site wastewater treatment facility or a cesspool, or is ordered by the Director to close an abandoned facility shall:

1. Remove all sewage from the facility and dispose of the sewage in a lawful manner;

2. Disconnect and remove electrical and mechanical components;

3. Remove or collapse the top of any tank or containment structure.
a. Punch a hole in the bottom of the tank or containment structure if the bottom is below the seasonal high groundwater table;

b. Fill the tank or containment structure or any cavity resulting from its removal with earth, sand, gravel, concrete, or other approved material; and

c. Regrade the surface to provide drainage away from the closed area;

4. Cut and plug both ends of the abandoned sewer drain pipe between the building and the on-site wastewater treatment facility not more than 5 feet outside the building foundation if practical, or cut and plug as close to each end as possible; and

5. Notify the Department within 30 days of closure.

E. Proprietary and other reviewed products.

1. The Department shall maintain a list of proprietary and other reviewed products that may be used for on-site wastewater treatment facilities to comply with the requirements of this Article. The list shall include appropriate information on the applicability and limitations of each product.

2. The list of proprietary and other reviewed products may include manufactured systems, subsystems, or components within the treatment works and disposal works if the products significantly contribute to the treatment performance of the system or provide the means to overcome site limitations. The Department will not list septic tanks, effluent filters or components that do not significantly affect treatment performance or provide the means to overcome site limitations.

3. A person may request that the Department add a product to the list of proprietary and other reviewed products. The request may include a proposed reference design for review. The Department shall ensure that performance values in the list reflect the treatment performance for defined wastewater characteristics. The Department shall assess fees under 18 A.A.C. 14 for product review.

F. Recordkeeping. A permittee authorized to discharge under one or more Type 4 General Permits shall maintain the Discharge Authorization and associated documents for the life of the facility.

Disclaimer: These regulations may not be the most recent version. Arizona 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.
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