Information on the state of Arizona is available for the following topics. To review this information, click on the links below.
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Edwin K. Swanson,
P.E., Senior Environmental Engineer, or
Charles G. Graf, Deputy Director, Water Quality Department
Arizona Department of Environmental Quality
3033 North Central Avenue
Phoenix, Arizona 85012
(602) 207-4440 or (602) 207-4661 (respectively)
(602) 207-4528 (fax)
Statutes & State Codes:
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Arizona State Regulations
Constitutions, Statutes and Codes
for the Design and Installation of
Septic Tank Systems and Alternative On-Site Disposal Systems
Engineering Bulletin No. 12
January 1, 2001
New state regulations for Arizona became effective January 1, 2001, and technical corrections are being prepared. Final action o the technical corrections is expected in mid 2002.
The following technologies are approved for the state: septic tank with disposal by trench, bed, chamber, or seepage pit; composting toilet; pressure distribution system; gravelless trench; natural seal evapotranspiration or lined evapotranspiration bed; Wisconsin mound; engineered pad system; intermittent sand filter with underdrain system or bottomless filter design; peat and textile filters; RUCK® system; sewage vault; aerobic system with subsurface or surface disposal; cap system; constructed wetland; sand-lined trench; disinfection device; sequencing batch reactor; and subsurface drip irrigation.
For any technology not listed above, the protocols for use are specified in Arizona Administrative Code R18-9-A210, R18-9-A309(E) and R18-9-A312(G). The applicable rule is dependent on the type of approval sought. Any technology is allowed for surface discharge, provided that (a) the treatment satisfies Arizona Administrative Code R18-9-E316(B), (b) all treated wastewater discharged to the land surface is totally contained on the property and the discharge is not hydraulically connected to the Waters of the United States, and (c) all other requirements of Arizona Administrative Code Title 18, Chapter 9, Article 3 are satisfied for notification, design, installation, and operation.
Discharge from an onsite wastewater treatment facility pursuant to Arizona Administrative Code Title 18, Chapter 9, Article 3 prohibits any discharge that is hydraulically connected to the Waters of the United States.
State Code allows drainfield area/size reduction. Applying the design criteria in Arizona Administrative Code Title 18, Chapter 9, Article 3 results in a calculated design absorption surface area that is determined by the daily design flow and the adjusted soil absorption rate [see the equation given in Arizona Administrative Code R18-9-A312(D)(3), which considers site/soil characteristics and the BOD and TSS in the treated wastewater]. A description of the equation used to calculate the adjusted soil absorption rate (when the treated wastewater quality is better than septic tank effluent) is available with a user-friendly table by electronic request with a return US Postal Service address at firstname.lastname@example.org
The design absorption surface area is determined by a calculation that considers the daily design flow and the adjusted soil absorption rate [see the equation given in Arizona Administrative Code R18-9-A312(D)(3), which considers site/soil characteristics and the BOD and TSS in the treated wastewater.
State level funding programs exist to assist homeowners with replacement of failing systems or installation of new systems; however, funding for individual residential systems is not significant at this time (CY 2001). For information, please contact Greg Swartz, Executive Director, Water Infrastructure Finance Authority, 202 E. Earll Drive, Suite 480, Phoenix, AZ 85012, (602) 230-9770, (602) 230-1480 (fax), or Greg.Swartz@wifa.state.az.us
Onsite wastewater demonstration, research, and testing projects are ongoing in Arizona, currently the Northern Arizona University Project and two (2) CWA Sec 319 Grant Projects. Information may be obtained from:
Dr. Paul Trotta,
Onsite Wastewater Demonstration Program
Northern Arizona University
College of Engineering
PO Box 15600
Flagstaff, AZ 86004
(520) 526-3114 (fax)
Arizona Code does not now recognize or require management programs/contracts or management districts to monitor and maintain onsite systems or individual liquid waste systems. There is no plan to adopt rules for maintenance/management contracts for onsite wastewater treatment facilities regulated under Arizona Administrative Code Title 18, Chapter 9, Article 3. However, local agencies have the authority to adopt or require maintenance/management programs.
The number of permits issued per year in Arizona is tracked for new construction but not for system repair or replacement. Records are maintained at the Arizona Department of Environmental Quality, based on data submitted by the 15 counties. The Department has delegated the review and approval of onsite wastewater treatment facilities covered by Arizona Administrative Code Title 18, Chapter 9, Article 3.
System failure is not specifically defined in the rule. Property owners responsible for the operation of an onsite wastewater treatment facility under Arizona Administrative Code Title 18, Chapter 9, Article 3 may operate the facility only under the terms and conditions of the general permit rule. If they do not operate according to the terms and conditions, then they are operating without a permit, which has significant sanctions. The provisions of Arizona Administrative Code R18-9-A307, R18-9-A308, and R18-9-A309(A) are critical terms and conditions related to failure. The provisions of statute, namely ARS 49-141(A)(1), (2), (3), (5), and (6), address failure based on environmental nuisances. Although there is no statewide scientific study of failure causes, poor siting, inadequate capacity, improper construction, and use beyond the useful service life are often noted.
There is no required licensing/certification program for designers, installers, inspectors, or site evaluators pursuant to Arizona Administrative Code Title 18, Chapter 9, Article 3. However, the Arizona Registrar of Contractors administers a program for licensing installers of onsite systems as license types C-41, L-41, and K-41.
There is no State licensing or certification program for performing site evaluations/inspections for onsite wastewater treatment facilities pursuant to Arizona Administrative Code Title 18, Chapter 9, Article 3.
Municipal wastewater regulations may be obtained by contacting Michele Robertson, Manager, Water Permits Section, Arizona Department of Environmental Quality at (602) 207-4428 or by emailing Robertson.Michele@ev.state.az.us
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of onsite systems: About 325,000 (1990 U.S. census reports approx 283,000).
Number of new systems installed each year: About 11,000-16,000.
Failure definition: Surfacing on ground, long-term backup, direct discharge to surface water or
groundwater which leads to a standards violation or direct public health problem.
Number or proportion of systems presently failing: About 0.5% (of which authorities are
aware), but the figure could be as high as 1%; by another report, approximately 2000.
Number or proportion repaired annually: About 0.5%; by another report, approximately 5000.
Number or proportion replaced annually: About 0.25%; by another report, approximately
Number or proportion of repairs or replacements that require alternative technology (e.g.,
sand filters, pressure dosing): Virtually none by one report; about half (500) by another; and
about 10% by still another; clearly the word alternative has been interpreted in different ways.
Number or proportion of repairs or replacements that require advanced technology (e.g.,
disinfection, nutrient removal): Virtually none by one report; about one-third by another; and
about 5% by still another; clearly the word advanced has been interpreted in different ways.
Cost of a conventional septic system installation: $1200-$4000, perhaps $3000 on average, but
up to $12,000.
Cost of a centralized sewer tie-in (including fees and cost of the sewer lateral): $750-$5000;
but up to $15,000 in difficult situations.
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No information available on Onsite Demonstration Programs in Arizona.
No information available on Onsite Management Communities in Arizona.