Ariz. Admin. Code § R18-5-408 - On-Site Wastewater Treatment Facilities

A. "On-site wastewater treatment facility" has the meaning defined in A.R.S. § 49-201(29) On-site wastewater treatment facilities shall be governed by A.A.C. Title 18, Chapter 9, Articles 1 and 3.
B. Where soil conditions and terrain features or other conditions are such that on-site wastewater treatment facilities cannot be expected to function satisfactorily or where groundwater or soil conditions are such that on-site wastewater treatment facilities may cause pollution of groundwater, they are prohibited.
C. Where such installations may create an unsanitary condition or public health nuisance, on-site wastewater treatment facilities are prohibited.
D. The use of cesspools is prohibited.
E. Where an on-site wastewater treatment facility is proposed, the following conditions shall be satisfied:
1. A geological report shall be made by an engineer, geologist or other person who meets the qualifications in R18-9-A310(H). The geological report shall include the total nitrogen discharge requirements of R18-9-A309(8)(c). The geological report shall include results from percolation tests and boring logs obtained at locations designated by the county health departments. There shall be a minimum of one percolation test and boring log per acre, or one percolation test and boring log per lot where lots are larger than one acre, except when it can be shown by submission of other reliable data that soil conditions are such that on-site wastewater treatment facilities could reasonably be expected to function properly on each lot in the proposed subdivision. The Department may require additional tests when it deems necessary. Percolation tests shall be performed in accordance with all of the requirements in R18-9-A310(F), except for the requirements in R18-9-A310(F)(1)(a). The approval of a subdivision, based upon such reports, shall not extend to the plat if it is further subdivided or lot lines are substantially relocated.
2. Results of all tests shall be submitted to the Department and the local health department for review and approval of the subdivision for the use of on-site wastewater treatment facilities.
3. Such approval must be obtained in writing from the local health department and a copy of the approval shall be submitted to the Department with the subdivision application for approval.

Notes

Ariz. Admin. Code § R18-5-408
Former Section R9-8-1027 renumbered without change as Section R18-5-408 (Supp. 89-2). Amended by final expedited rulemaking at 31 A.A.R. 985, effective 3/7/2025.

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