Current through Register Vol. 30, No. 38, September 20, 2024
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 a 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 would otherwise be covered under other general permits, but are
either sized larger to accommodate increased flows or, will be located at a
site that cumulatively accommodates flows between 3000 gallons per day to less
than 24,000 gallons per day;
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 that would otherwise be covered by one of the following general
permits available for a design flow of less than 3000 gallons per day:
a. An aerobic system as described in
R18-9-E315;
b. A disinfection device described in
R18-9-E320, except that an
ultraviolet radiation disinfection device is allowed; or
c. A seepage pit or pits described in
R18-9-E302;
and
4. The discharge of
total nitrogen to groundwater is controlled.
a. An applicant shall:
i. Demonstrate that the nitrogen loading
calculated 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
calculated at a horizontal plane immediately beneath the zone of active
treatment of the on-site wastewater treatment facility including its disposal
field; or
ii. Justify a nitrogen
loading that is equally protective 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 determine the nitrogen concentration in the treated wastewater 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, schedules, and estimated annual costs for
operating, maintaining, 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
professional 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 specified 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 following 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 submitted with the Engineer's
Certificate of Completion.
2. The name of the service provider or
certified operator that is responsible for implementing the performance
assurance 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 provider 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 or site
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 waste-water treatment facility in order to add the facility to the
existing site operating under this section.
1.
The applicant shall indicate in the Notice of Intent to Discharge 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 property to equal or exceed 24,000 gallons per day, the
Director 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.
