Section R18-9-E323. 4.23 General Permit: 3000 to less than 24,000 Gallons Per Day Design Flow

A.      A 4.23 General Permit allows for the construction and use of an on-site wastewater treatment facility with a design flow from 3000 gallons per day to less than 24,000 gallons per day

or more than one on-site wastewater treatment facility on a property or on adjacent properties under common ownership with an combined design flow from 3000 to less than 24,000 gallons per day if all of the following apply:

1.        Except as specified in subsection (A)(3), the treatment and disposal works consists of technologies or designs that are covered under other general permits, but are sized larger to accommodate increased flows;

2.        The on-site wastewater treatment facility complies with all applicable requirements of Articles 1, 2, and 3 of this Chapter;

3.        The facility is not a system or a technology covered by one of the following general permits available for a design flow of less than 3000 gallons per day:

a.         An aerobic system with subsurface or surface dis- posal described in R18-9-E315;

b.        A disinfection device described in R18-9-E320; or

c.         A seepage pit or pits described in R18-9-E302; and

4.        The discharge of total nitrogen to groundwater is con- trolled.

a.         An applicant shall:

i.         Demonstrate that the nitrogen loading calcu- lated over the property served by the on-site wastewater treatment facility, including streets, common areas, and other non-contributing areas, is not more than 0.088 pounds (39.9 grams) of total nitrogen per day per acre calcu- lated at a horizontal plane immediately beneath the zone of active treatment of the on-site wastewater treatment facility including its dis- posal field; or

ii.        Justify a nitrogen loading that is equally protec- tive of aquifer water quality as the nitrogen loading specified in subsection (A)(4)(a)(i) based on site-specific hydrogeological or other factors.

b.        For purposes of the demonstration in subsection (A)(4)(a)(i), the applicant may assume that 0.0333 pounds (15.0 grams) of total nitrogen per day per person is contributed to raw sewage and may deter- mine the nitrogen concentration in the treated waste- water at a horizontal plane immediately beneath the zone of active treatment of the on-site wastewater treatment facility including its disposal field.

B.       Notice of Intent to Discharge. In addition to the Notice of Intent to Discharge requirements specified in R18-9-A301(B) and R18-9-A309(B), an applicant shall submit:

1.        A performance assurance plan consisting of tasks, sched- ules, and estimated annual costs for operating, maintain- ing, and monitoring performance over a 20-year operational life;

2.        Design documents and the performance assurance plan, signed, dated, and sealed by an Arizona-registered pro- fessional engineer;

3.        Any documentation submitted under the alternative design procedure in R18-9-A312(G) that pertains to achievement of better performance levels than those specified in the general permit for the corresponding facility with a design flow of less than 3000 gallons per day, or for any other alternative design, construction, or operational change proposed by the applicant; and

4.        A demonstration of total nitrogen discharge control spec- ified in subsection (A)(4).

C.      Design requirements. The applicant shall comply with the applicable requirements in R18-9-A312 and the applicable

general permits for the treatment works and disposal works used in the design of the on-site wastewater treatment facility.

D.      Installation requirements. The applicant shall comply with the applicable requirements in R18-9-A313(A) and the applicable general permits for the treatment works and disposal works used in the design of the on-site wastewater treatment facility.

E.       Operation and maintenance requirements. The applicant shall comply with the applicable requirements in R18-9-A313(B) and the applicable general permits for the treatment works and disposal works used in the design of the on-site wastewater treatment facility.

F.       Additional Discharge Authorization requirements. In addition to any other requirements, the applicant shall submit the fol- lowing information before the Discharge Authorization is issued.

1.        A signed, dated, and sealed Engineer’s Certificate of Completion in a format approved by the Department affirming that:

a.         The project was completed in compliance with the requirements of this Section and as described in the plans and specifications, or

b.        Any changes are reflected in as-built plans submit- ted with the Engineer’s Certificate of Completion.

2.        The name of the service provider or certified operator that is responsible for implementing the performance assur- ance plan.

G.      Reporting requirement. The permittee shall provide the Department with the following information on the anniversary date of the Discharge Authorization:

1.        A form signed by the certified operator or service pro- vider that:

a.         Provides any data or documentation required by the performance assurance plan,

b.        Certifies compliance with the requirements of the performance assurance plan, and

c.         Describes any additions to the facility during the year that increased flows and certifies that the flow did not exceed 24,000 gallons per day during any day; and

2.        Any applicable fee required by 18 A.A.C. 14.

H.      Facility expansion. If an expansion of an on-site wastewater treatment facility operating under this Section involves the installation of a separate on-site wastewater treatment facility on the property with a design flow of less than 3000 gallons per day, the applicant shall submit the applicable Notice of Intent to Discharge and fee required under 18 A.A.C. 14 for the separate on-site wastewater treatment facility.

1.        The applicant shall indicate in the Notice of Intent to Dis- charge the Department’s file number and the issuance date of the Discharge Authorization previously issued by the Director under this Section for the property.

2.        Upon satisfactory review, the Director shall reissue the Discharge Authorization for this Section, with the new issuance date and updated information reflecting the expansion.

3.        If the expansion causes the accumulative design flow from on-site wastewater treatment facilities on the prop- erty to equal or exceed 24,000 gallons per day, the Direc- tor shall not reissue the Discharge Authorization,  but shall require the applicant to submit an application for an individual permit addressing all proposed and operating facilities on the property.

Historical Note

New Section adopted by final rulemaking at 7 A.A.R. 235, effective January 1, 2001 (Supp. 00-4). Amended by final rulemaking at 11 A.A.R. 4544, effective November

12, 2005 (05-3).