Other Components

01. Design Approval Required. Commercially manufactured wastewater treatment components and systems must not be used in constructing a subsurface sewage system unless the design is approved by the Director. Depth of Aggregate: Total Over Distribution Laterals Under Distribution Laterals 12 In. Minimum 2 In. Minimum 6 In. Minimum Depth of Soil Over Top of Aggregate 12 In. Minimum STANDARD SUBSURFACE DISPOSAL FACILITY SPECIFICATIONS Item All Soil Groups IDAHO ADMINISTRATIVE CODE IDAPA 58.01.03 – Individual/Subsurface Sewage Department of Environmental Quality Disposal & Cleaning of Septic Tanks Rules Section 009 Page 20 The Department developed recommended standards and guidance for these systems in the TGM. Approval may be limited to those locations or conditions where achievement of standards has been demonstrated. Commercially manufactured wastewater treatment components and systems may include but are not limited to: (7-1-25) a. ETPSs (e.g., aerobic treatment systems); (3-31-22) b. PWTPs; and (7-1-25) c. Proprietary non-discharging systems (e.g., individual wastewater incinerators, composting toilets, or vault toilets). (3-31-22) 02. Plan and Specification Submittal. Plans and specifications for all commercially manufactured wastewater treatment components and systems must be submitted to the Director for approval. Plans and specifications must include detailed construction drawings; capacities; structural calculations; lists of materials; performance standards; manufacturers’ installation, operation, and maintenance instructions; installation inspection checklist; and other relevant information requested by the Director. (7-1-25) a. Manufacturers seeking approval for ETPSs or PWTPs that reduce total suspended solids (TSS) and carbonaceous biological oxygen demand 5-day (CBOD5) when used with residential strength wastewater must submit NSF/ANSI 40 approvals, reports, and associated data or equivalent third-party standards. (7-1-25) b. Manufacturers seeking approval for ETPSs or PWTPs that reduce total nitrogen (TN) must submit NSF/ANSI 245 approvals, reports, and associated data or equivalent third-party standards. (7-1-25) 03. ETPS. (7-1-25) a. In addition to the items in Subsection 009.02, ETPS plan and specification submittals must include: (7-1-25) i. A plan for training and certifying system installers and service providers under Section 006; (3-31-22) ii. A manual containing all operation and maintenance specified by the design engineer or manufacturer and the Department; and (7-1-25) iii. A quality assurance project plan documenting how sampling will occur if required by the Director for product approval and continued monitoring. (7-1-25) b. Design and installation of these systems must meet the following: (3-31-22) i. The effluent is discharged to a drainfield meeting the requirements of a standard drainfield as directed in Section 008 or a Director-approved alternative. (3-31-22) ii. If vertical separation distances are reduced from the distances defined in the table in Subsection 008.01.c., the reduced separation must protect groundwater quality and a sampling port must be installed to provide access to representative samples of the effluent from the system. (7-1-25) c. Within thirty (30) days of completing installation of an ETPS, the property owner must provide certification to the health district from a representative approved by the manufacturer that the system has been installed and will operate in accordance with the manufacturer’s recommendations. The health district must not finalize the installation permit until the certification of proper installation and operation is received and includes information on the manufacturer, product, model number, and serial number of the ETPS installed. (7-1-25) d. Property owners with an ETPS installed on their property must have all operation, maintenance, and monitoring requirements specified in the permit completed by June 30 of each year by a certified service provider in accordance with Section 006, including effluent monitoring if required by the permit. The certified service IDAHO ADMINISTRATIVE CODE IDAPA 58.01.03 – Individual/Subsurface Sewage Department of Environmental Quality Disposal & Cleaning of Septic Tanks Rules Section 010 Page 21 provider who completed operation, maintenance, and monitoring for the system as specified in the TGM must submit an annual report to the Director by July 31 of each calendar year demonstrating the system is working as designed. (7-1-25) e. Permit requirements for ETPSs transfer with ownership changes. Before transferring ownership of a property with an ETPS, the system owner must notify all transferees of the ETPS operation, maintenance, and monitoring requirements. (7-1-25) 04. PWTPs. (7-1-25) a. System media used with a PWTP must: (7-1-25) i. Be constructed or manufactured from materials that are non-decaying and non-deteriorating and do not leach unacceptable chemicals when exposed to sewage and the subsurface soil environment; (3-31-22) ii. Support the distribution pipe and provide suitable effluent distribution and infiltration rate to the absorption area at the soil interface; and (3-31-22) iii. Maintain the integrity of the trench or bed. The material used, by its nature and manufacturer- prescribed installation procedure, must withstand the physical forces of the soil sidewalls, soil backfill, and weight of equipment used in the backfilling. (7-1-25) b. Drainfield size is based on the requirements of a standard drainfield or the manufacturer’s recommended minimum sizing requirement; and (7-1-25) c. A system using a PWTP may be required to follow the same operation, maintenance, monitoring, and reporting requirements described in Subsection 009.03.d. due to product complexity and site-specific constituent reduction requirements. (7-1-25) d. Permit requirements for these systems transfer with ownership changes. Before transferring ownership of a property with this system, the system owner must notify all transferees of the system operation, maintenance, and monitoring requirements. (7-1-25) 05. Design Approval Effect. The Director may condition a design approval by specifying circumstances under which the component must be installed, used, operated, maintained, or monitored. (7-1-25) a. The Director will specify the complex alternative systems that must undergo professionally managed operation, maintenance, service, or effluent testing. (7-1-25) b. Manufacturers will provide training to a reasonable number of service providers to perform required operation, maintenance, or monitoring as specified by the Director. (7-1-25) c. Manufacturers may enter into agreements with certified service providers trained in their technology but must not limit service providers from training in the technology of other manufacturers. (7-1-25) 06. Design Disapproval Notice. If the Director determines the component described in the submittal does not comply with or may not consistently function in compliance with these rules, or the manufacturer of the proposed system failed to comply with Subsection 009.03, the Director will disapprove the design as submitted and notify the manufacturer or distributor submitting the design, in writing, of the disapproval and the reason for that action. (7-1-25)