IDAPA 58.01.03
This rule applies to individual land and home owners who wish to install or operate individual septic systems to treat and dispose of sewage via a subsurface sewage disposal system and every individual subsurface blackwaste and wastewater treatment system in Idaho.
This rule establishes limitations on the construction and use of individual and subsurface sewage disposal systems and establishes the requirements for obtaining an installation permit and an installer's registration permit.
This rule implements the following statutes passed by the Idaho Legislature:
Health and Safety:
James Craft Department of Environmental Quality 1410 N. Hilton Boise, ID 83706 Phone: (208) 373-0488 Email: james.craft@deq.idaho.gov www.deq.idaho.gov
This rule chapter will be reviewed in compliance with Section 67-5292, Idaho Code, and in accordance with the 8-year rule review schedule linked here.
58.01.03 – Individual/Subsurface Sewage Disposal Rules and Rules for Cleaning of Septic Tanks
000. Legal Authority. ... 3
001. Scope, Conflict, And Responsibilities. ... 3
002. Referenced Material. ... 3
003. Definitions. ... 3
004. General Requirements. ... 6
005. Permit And Permit Application. ... 7
006. Registration Permits for Installers and Service Providers. ... 10
007. Septic Tanks Design And Construction Standards. ... 12
008. Standard Subsurface Disposal Facility Design And Construction. ... 16
009. Other Components. ... 19
010. Variances. ... 21
011. Inspections. ... 22
012. Violations And Penalties. ... 23
013. LSAS. ... 23
014. -- 049. (Reserved) ... 26
050. Septic Tank Cleaning. ... 26
051. -- 995. (Reserved) ... 27
996. Administrative Provisions. ... 27
997. -- 999. (Reserved) ... 27
AND RULES FOR CLEANING OF SEPTIC TANKS
Title 39, Chapter 1 and Title 39, Chapter 36, Idaho Code. (7-1-25)
01. Scope. These rules: (7-1-25)
a. Establish limits on the construction and use of individual and subsurface sewage disposal systems; (7-1-25)
b. Establish requirements for obtaining an installation permit and registration permits for installers, service providers, and pumpers; (7-1-25)
c. Apply to every individual and every subsurface blackwaste and wastewater treatment system in Idaho; and (7-1-25)
d. Establish general requirements for handling, transportation, and disposal of septic tank wastes. (7-1-25)
02. Conflict of Rules, Standards, and Ordinances. Where a provision of these rules conflicts with a provision of any state or local zoning, building, fire, safety, or health regulation, standard, or ordinance, the provision that, in the Director’s judgment, establishes the higher standard for promoting and protecting the health and safety of the people prevails. (7-1-25)
03. Responsibilities. (3-31-22)
a. Every owner of real property is jointly and individually responsible for: (3-31-22)
i. Storing, treating, and disposing of blackwaste and wastewater generated on that property. (3-31-22)
ii. Connecting all plumbing fixtures on the property that discharge wastewaters to an approved wastewater system or facility. (7-1-25)
iii. Obtaining necessary permits and approvals for installing individual or subsurface blackwaste and wastewater disposal systems. (7-1-25)
iv. Abandoning an individual or subsurface sewage disposal system. (7-1-25)
b. Each engineer, building contractor, individual or subsurface disposal system installer, excavator, plumber, supplier, and any person, who designs, constructs, abandons, or provides any system or component, is jointly and individually responsible for compliance with all rules relevant to that service or product. (7-1-25)
01. NSF International. The NSF International (NSF) NSF/ANSI 40: Residential Onsite Systems and NSF/ANSI 245: Nitrogen Reduction are referenced and are available at www.nsf.org/services/by-industry/water-wastewater/onsite-wastewater. (7-1-25)
02. Technical Guidance Manual for Individual Subsurface Sewage Disposal Systems (TGM). The TGM is referenced and available at Department of Environmental Quality, 1410 N. Hilton St., Boise, ID 83706. (7-1-25)
The terms “Department,” “Director,” and “Waters” are defined in Section 39-103, Idaho Code. The term “Ground water” (Groundwater) is defined in Section 39-121, Idaho Code. (7-1-25)
01. Abandoned System. A system that no longer receives blackwaste or wastewater due to diversion to another treatment system or due to termination of waste flow for more than two (2) years. (7-1-25)
02. Absorption Bed. A drainfield excavation exceeding six (6) feet in width. (7-1-25)03. Alternative System. Any system other than a standard system for which the Department has issued design guidelines or the Director determines is a modification of a standard system. (7-1-25)a. A basic alternative system is any capping fill system, extra drainrock trench, gravelless trench system, steep-slope system, or other system specified in the TGM. (7-1-25)b. A complex alternative system is any evapotranspiration system, ETPS, lagoon system, LSAS, pressure distribution system, PWTP system, intermittent sand filter, sand mound, or other system specified in the TGM. (7-1-25)04. Bedroom. A habitable room within a dwelling that meets state or local building code requirements applicable to bedrooms and includes methods of ingress and egress. The local building authority may designate any additional room as a bedroom. (7-1-25)05. Blackwaste. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)06. Blackwater. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)07. Building Sewer. The extension of the building drain beginning five (5) feet outside the inner face of the building wall. (3-31-22)08. Central System. Any system that receives blackwaste or wastewater in volumes exceeding twenty-five hundred (2,500) gallons per day; any system that receives blackwaste or wastewater from more than two (2) dwelling units or more than two (2) buildings under separate ownership. (7-1-25)09. Construct. To make, form, excavate, alter, expand, repair, or install a system. (7-1-25)10. Drainfield. A system of aggregate-filled trenches, gravelless chamber systems, drip systems, absorption beds, or other approved subsurface dispersal methods that distribute wastewater effluent into the soil. Also known as a “leachfield” or “soil absorption system.” (7-1-25)11. Dwelling Unit. A single unit with complete independent living facilities for one (1) or more persons, including permanent improvements for living, sleeping, eating, cooking, and sanitation. (7-1-25)12. Existing System. Any system installed before the effective date of these rules. (7-1-25)13. Expand. To enlarge any nonfailing system. (3-31-22)14. Extended Treatment Package System (ETPS). A wastewater treatment product that requires electricity and provides secondary or tertiary wastewater treatment to septic tank effluent for systems receiving less than twenty-five hundred (2,500) gallons per day. (7-1-25)15. Failing System. Any system that exhibits one (1) or more of the following characteristics: (7-1-25)a. Does not meet the intent stated in Subsection 004.01. (7-1-25)b. Fails to accept blackwaste and wastewater; or (7-1-25)c. Discharges blackwaste or wastewater into the waters or onto the ground surface. (7-1-25)16. Gray Water. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)17. High Groundwater Level -- Normal, Seasonal. High groundwater level may be established by the soil characteristics, actual groundwater monitoring, or historic records. (7-1-25)
a. Normal high groundwater level is the highest elevation of groundwater that is maintained or exceeded continuously for six (6) weeks a year. (7-1-25)
b. The seasonal high groundwater level is the highest elevation of groundwater that is maintained or exceeded continuously for one (1) week a year. (7-1-25)
18. Individual System. Any standard, alternative, or subsurface disposal system that is not a central system. (7-1-25)
19. Install. To excavate or put in place a system or component of a system. (7-1-25)
20. Installer. Any person, corporation, or firm engaged in the business of excavation or construction of individual or subsurface sewage disposal systems in the State. (7-1-25)
21. Large Soil Absorption System (LSAS). A subsurface sewage disposal system designed to receive two thousand five hundred (2,500) gallons of wastewater or more per day, including where the total wastewater flow from the entire proposed project exceeds two thousand five hundred (2,500) gallons per day, but is separated into absorption modules that receive less than two thousand five hundred (2,500) gallons per day. (7-1-25)
22. Limiting Layer. A subsurface layer or material that severely limits the capability of the soil to treat or absorb wastewater including, but not limited to, water tables, fractured bedrock, excessively permeable material, and impermeable material. (7-1-25)
23. Manufactured Medium Sand. Sand that meets the following gradation requirements:
| Manufactured medium sand allowable particle size percent composition. | |
|---|---|
| Sieve Size | Passing (%) |
| 4 | 95–100 |
| 8 | 80–100 |
| 16 | 50–85 |
| 30 | 25–60 |
| 50 | 10–30 |
| 100 | 2–10 |
| 200 | <2 |
(3-31-22)
24. Minimum Tank Capacity. The minimum required total liquid capacity of the septic tank facility. (7-1-25)
25. New System. A system that is or might be approved on or after the effective date of these rules. (7-1-25)
26. Nondischarging System. Any system designed and constructed to prevent subsurface discharge of blackwaste or wastewater. (7-1-25)
27. Pollutants. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)
28. Proprietary Wastewater Treatment Product (PWTP). A manufactured product that provides passive treatment to septic tank effluent for systems receiving less than twenty-five hundred (2,500) gallons per day. (7-1-25)
29. Repair. To remake, reform, replace, or enlarge a failing system, or any component as is necessary to restore proper operation. (7-1-25)
30. Scarp. The side of a hill, canyon, ditch, river bank, roadcut, or other geological feature characterized by a slope of forty-five (45) degrees (100% slope) or more from the horizontal. (7-1-25)
31. Septic Tank. A watertight, covered receptacle designed and constructed to receive wastewater discharge, separate solids from liquid, digest organic matter, store digested solids through a period of detention, and allow clarified liquids to discharge for final disposal. (7-1-25)
32. Septic Tank Facility. A septic tank or series of septic tanks preceding a subsurface disposal system. Tanks or compartments used for housing pretreatment products or used as dosing chambers are not considered part of the septic tank facility. (7-1-25)
33. Septage. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)
34. Service Provider. Any person, corporation, or firm engaged in the business of providing operation, maintenance, and monitoring of complex alternative systems in the state of Idaho. (3-31-22)
35. Sewage. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)
36. Standard System. An effluent sewer, one (1) or more aggregate filled trenches, and a gravity flow wastewater distribution system. (7-1-25)
37. Subsurface Disposal System. Any system with a point of discharge beneath the earth’s surface. (7-1-25)
38. Surface Water - Intermittent, Permanent, Temporary. (3-31-22)
a. Any waters including but not limited to, lakes, streams, canals, and ditches. (7-1-25)
b. Intermittent surface water exists continuously for more than two (2) months but not more than six (6) months a year. (7-1-25)
c. Permanent surface water exists continuously for more than six (6) months a year. (7-1-25)
d. Temporary surface water exists continuously for less than two (2) months a year. (7-1-25)
39. System. Beginning at the point of entry, physically connected piping, treatment devices, receptacles, structures, or areas of land designed, used or dedicated to convey, store, stabilize, neutralize, treat, or dispose of blackwaste or wastewater. (7-1-25)
40. Trench. A drainfield excavation six (6) feet or less in width. (7-1-25)
41. Wastewater. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)
01. Intent of Rules. The Idaho Board of Environmental Quality, to protect the health, safety, and environment of the people of the state of Idaho establishes these rules governing the design, construction, siting and abandonment of individual and subsurface sewage disposal systems. These rules are intended to ensure that blackwastes and wastewater generated in the state of Idaho are safely contained and treated and that blackwaste and wastewater contained in or discharged from each system: (7-1-25)
a. Are not accessible to insects, rodents, or other wild or domestic animals; (3-31-22)
b. Are not accessible to individuals; (3-31-22)
c. Do not create a public nuisance due to odor or unsightly appearance; (7-1-25) d. Do not injure or interfere with existing or potential beneficial uses of the waters; and (7-1-25) e. Do not have an adverse impact on public health or the environment. (7-1-25)
02. Compliance with Intent. The Director will not authorize or approve any system if, in the Director's opinion, the system will not (does not) comply with the intent of these rules. (7-1-25)
03. System Limitations. Cooling water, backwash or backflush water, hot tub or spa water, air conditioning water, water softener brine, groundwater, oil, roof drainage, or other substances detrimental to the system's performance or to groundwater quality cannot be discharged into any system unless that discharge is approved by the Director. (7-1-25)
04. Increased Flows. Unless authorized by the Director, it is unlawful for any person to provide for or connect additional blackwaste or wastewater sources to any system if the resulting flow or volume would exceed the approved design flow of the system. (7-1-25)
05. Failing System. The owner of any failing system must obtain a permit and repair the failing system: (7-1-25)
a. As soon as practical after the owner becomes aware of its failure; or (3-31-22) b. As directed with proper notice from the Director. (7-1-25)
06. Subsurface Disposal System Replacement Area. An area of land suitable for the complete replacement of a new subsurface disposal system disposal field must be reserved as a replacement area. This area must be kept vacant, free of vehicular traffic, and free of any soil modification that would negatively affect its use as a replacement disposal field construction site. (7-1-25)
07. Technical Guidance Committee (TGC). The Director appoints a TGC composed of three (3) representatives from the seven (7) health districts, one (1) representative from the Department, one (1) professional engineer licensed in the state of Idaho and one (1) licensed installer. Appointments to vacancies are three (3) year terms. (7-1-25)
08. TGC Duties. The TGC maintains the TGM used in the design, construction, alteration, operation, and maintenance of conventional systems, their components, and alternatives. The TGC reviews variance requests and commercially manufactured wastewater treatment components and systems at the request of the Director and provides recommendations. (7-1-25)
09. TGM. The TGM maintained by the TGC provides technical guidance on alternative sewage disposal components and systems, soil type determination methodology, and other information pertinent to the best management practices of individual and subsurface sewage disposal. (7-1-25)
10. Alternative System. If a standard system cannot be installed on a parcel of land, an alternative system may be permitted if that system is installed in accordance with the TGC's recommendations and is approved by the Director as stated in Section 009. (7-1-25)
005. PERMIT AND PERMIT APPLICATION.
01. Permit Required. Except as specified in Subsection 005.02 no person may modify, repair or expand or install any individual or subsurface sewage disposal system within the state of Idaho unless there is a valid installation permit authorizing that activity. (7-1-25)
02. Permit Exceptions. The activities listed in this subsection may be lawfully performed in the absence of a valid installation permit but are subject to all other relevant rules and regulations. (7-1-25)
a. Portable nondischarging systems may be installed as temporary blackwaste or wastewater systems if properly maintained and of a design approved by the Director. (7-1-25)
b. Individual and subsurface disposal systems may be repaired when needed due to clogged or broken solid piping or malfunctions in an electrical or mechanical system. Repairs may not expand the system unless authorized by the Director. (7-1-25)
03. Permit Application. The owner of the system or their authorized representative must submit the application to the Director in an approved form. (7-1-25)
04. Application Contents. Information required in the application may include, but is not limited to: (7-1-25)
a. Name and address of the owner of the system and of the applicant, if different; (7-1-25)
b. Legal description of the parcel of land; (7-1-25)
c. Type of establishment served; (7-1-25)
d. Maximum number of persons served, number of bedrooms, or other appropriate measure of wastewater flow; (7-1-25)
e. Type of system; (7-1-25)
f. Construction activity (new construction, enlargement, repair); (7-1-25)
g. Scaled or dimensioned plot plan including, if needed, adjacent properties illustrating: (7-1-25)
i. Location and size of all existing and proposed wastewater systems including disposal field replacement areas; (7-1-25)
ii. Location of all existing water supply system features; (7-1-25)
iii. Location of all surface waters; (7-1-25)
iv. Location of scarps, cuts, and rock outcrops; (7-1-25)
v. Land elevations, between features of interest; (7-1-25)
vi. Property lines, easements, and rights-of-way; and (3-31-22)
vii. Location and size of buildings and structures. (3-31-22)
h. Plans and specifications of the proposed system including: (7-1-25)
i. Diagrams of all system facilities made or fabricated at the site; (7-1-25)
ii. Manufacturer’s name and identification of any component approved under Sections 007 and 009; (7-1-25)
iii. List of materials. (3-31-22)
i. Site evaluation report that includes but is not limited to a soil description and profile and groundwater data; (7-1-25)
j. Nature and quantity of blackwaste and wastewater the system will receive, including the basis for
that estimate; (7-1-25)
k. Proposed operation, maintenance, and monitoring procedures to ensure the system’s performance and failure detection; (7-1-25)
l. Copies of legal documents relating to access and to responsibilities for operation, maintenance, and monitoring; (3-31-22)
m. Statement from the local zoning or building authority indicating the proposed system would not be contrary to local ordinances; (7-1-25)
n. Signature of the owner of the system and, if different, of the applicant; and (7-1-25)
o. Any other information, document, or condition required by the Director to substantiate that the system will comply with applicable rules and regulations. (7-1-25)
05. Permit Application Denial. The Director may deny a permit application if in the Director’s judgment: (7-1-25)
a. The application is incomplete, inaccurate, or misleading; (3-31-22)
b. The system as proposed is not in compliance with applicable rules and regulations; (3-31-22)
c. The public or central wastewater treatment facilities are reasonably accessible. (7-1-25)
06. Notice of Denial. Upon denial of an application the Director will notify the applicant of the reason for denial. (7-1-25)
07. Permit Issuance. When, in the Director’s opinion the system as proposed will conform with applicable rules, the Director will issue an “Individual and Subsurface System Installation Permit.” (7-1-25)
08. Valid Application and Permit. Unless otherwise stated on the application or permit, it will become invalid if the authorized construction or activity is not completed and approved within two (2) years of the date of issuance. (7-1-25)
09. Permit Renewal. At the Director’s discretion, a permit may be renewed upon request by the applicant or owner if the request is received by the Director before the permit’s date of expiration. (7-1-25)
10. Permit Effect. A valid permit authorizes the construction of an individual or subsurface disposal system and requires the construction be conducted in compliance with plans, specifications, and conditions contained in the approved permit application. Any deviation from the plans, specifications, or conditions is prohibited unless it is approved in advance by the Director. (7-1-25)
11. Abandonment. The Director may require as a condition for issuing a permit that the system be abandoned by a specified date or specific predetermined circumstances. The date or circumstances will be established before issuing the permit and be contained in the permit application. These conditions may relate to a specific date, dwelling density, municipal system completion or other circumstances regarding availability of central sewerage system services. (7-1-25)
12. Operation, Maintenance, and Monitoring. (7-1-25)
a. The Director may require, as a condition of issuing a permit, specific operation, maintenance, and monitoring procedures be observed. Those procedures will be contained in the installation permit. (7-1-25)
b. All operation, maintenance, and monitoring requirements of installation permits including effluent sampling must be perpetual unless: (7-1-25)
i. The system is not installed; (3-31-22) ii. The system is removed, abandoned, or replaced; or (3-31-22) iii. The permit is amended or revoked by the Director. (3-31-22) c. If a system is approved as described by the TGM, sampling requirements may be removed. (7-1-25)
13. Permit Fee. All applications must be accompanied by payment specified in IDAPA 58.01.14, “Rules Governing Fees for Environmental Operating Permits, Licenses, and Inspection Services”. (7-1-25)
006. REGISTRATION PERMITS FOR INSTALLERS AND SERVICE PROVIDERS.
01. Permit Required. Every installer and service provider must secure from the Director a registration permit. Two (2) types of installer permits and one (1) type of service provider permit are available. (7-1-25)
a. A basic system installer’s permit is required to install all individual systems not listed under Subsection 006.01.b. (7-1-25) b. A complex system installer’s permit is required to install evapotranspiration systems, ETPSs, lagoon systems, LSASs, pressure distribution systems, PWTP systems, intermittent sand filters, sand mounds, or other alternative systems specified in the TGM. (7-1-25) c. A service provider permit is required to perform operation, maintenance, or monitoring of ETPSs and any other Director-identified complex systems. (7-1-25)
02. Examination. The initial issuance of the installer’s or service provider’s permit will be based on completing an examination, with a passing score of seventy percent (70%) or more The installer and service provider examinations are separate. (7-1-25)
03. Permits Required Annually. Installer and service provider permits expire annually on the first (1st) day of January, and all permits issued thereafter will be for the balance of the calendar year. Additionally, installers will attend at least one (1) refresher course approved by the Department every three (3) years. (7-1-25)
04. Application Contents. (7-1-25)
a. Applications for installer and service provider permits must: (7-1-25) i. Be in writing; (7-1-25) ii. Be signed by the applicant or an officer or authorized agent of a corporation; (7-1-25) iii. Contain the name and address of the applicant; and (3-31-22) iv. Indicate whether the permit is for; (7-1-25) (1) Installation of standard and basic alternative systems; (3-31-22) (2) Installation of standard, basic and complex alternative systems; or (3-31-22) (3) A service provider; and (7-1-25) v. Contain the expiration date of the bond required by Subsection 006.05. (3-31-22)
b. Additionally, for applicants seeking a service provider permit, the application must contain documentation of manufacturer specific training, described in Subsection 006.06.a. (7-1-25)
05. Bond Required. At the time of application, all applicants seeking a basic or complex installer's permit, or a service provider permit must deliver to the Director a bond The bond must: (7-1-25)
a. Be in a form approved by the Director; (7-1-25) b. Be in the sum of ten thousand dollars ($10,000) for a basic installer's or service provider's permit, or thirty thousand dollars ($30,000) for a complex installer's permit; (7-1-25) c. Be executed by a surety company duly authorized to do business in the state of Idaho and run concurrent with the permit; and (7-1-25) d. Guarantee the installer or service provider's faithful performance of all work undertaken under the provisions of the installer's or service provider's permit, or both. (7-1-25)
06. Damages. Any person who suffers damage from negligent or wrongful acts of the installer or service provider or by the installer's or service provider's failure to competently perform any of the work agreed to be done under the terms of the registration permit will, in addition to other legal remedies, have a right of action on the bond for all damages not exceeding ten thousand dollars ($10,000) for standard and basic alternative systems or operation, maintenance, and monitoring by certified service providers or thirty thousand dollars ($30,000) for complex alternative systems. The maximum liability of the sureties on the bond, regardless of the number of claims filed against the bond, must not exceed the sum of ten thousand dollars ($10,000) for standard and basic alternative systems or operations, maintenance, and monitoring by certified service providers or thirty thousand dollars ($30,000) for complex alternative systems. (7-1-25)
07. Service Provider Responsibilities. All permitted service providers who operate, maintain, or monitor any system are responsible for compliance with all rules relevant to those services. Additionally, each service provider must: (7-1-25)
a. Obtain documentation of the completed manufacturer-specific training of each manufactured and packaged treatment system the service provider intends to operate, maintain, or monitor. Proper documentation includes a certificate or letter of training completion provided by the manufacturer and an expiration date of the manufacturer's certification. If a system manufacturer is no longer in business, that manufacturer-specific training is not required; (7-1-25) b. Maintain a comprehensive list of real property owners who contracted with the certified service provider, including the current real property owner name, service property address, real property owner contact address, and installation permit number. This list must be provided to the Director as part of the annual operation, maintenance, and monitoring reports for individual real property owners; (7-1-25) c. Notify the system owner in writing of any improper system function that cannot be remedied during operation, maintenance, and monitoring services; and (7-1-25) d. Submit all operation, maintenance, and monitoring records in an annual report for each individual real property owner for whom the service provider agrees to fulfill the real property owner's operation, maintenance, or monitoring responsibilities required in Subsection 009.03. The annual reports must be provided to the Director by the timeframe specified in the TGM for the specific alternative system for which operation, maintenance, or monitoring is required. (7-1-25)
08. Exemption. An installer's permit is not required for: (7-1-25)
a. Any person, corporation, or firm constructing a central or municipal subsurface sewage disposal system if that person, corporation, or firm is a licensed public works contractor, is experienced in the type of system to be installed and is under the direction of a professional engineer licensed in the state of Idaho; or (7-1-25) b. Owners installing their own standard or basic alternative system as described in the TGM. (7-1-25)
09. Application Fee. All applications must be accompanied by payment of the fee specified in IDAPA 58.01.14, “Rules Governing Fees for Environmental Operating Permits, Licenses, and Inspection Services.” (7-1-25)
01. Materials. New septic tanks will be constructed of concrete, or other materials approved by the Director. Steel tanks are unacceptable. (3-31-22)
02. Design. A professional engineer licensed by the state of Idaho must submit all septic tank designs to the Department for approval. If any design submitted for approval does not meet all requirements in Section 007, the engineer must demonstrate that any deviation is determined by sound engineering practice and meets the intent of the rules. (7-1-25)
03. Construction Requirements. All septic tanks will be water tight, constructed of sound, durable materials, and not subject to excessive corrosion, decay, frost damage or cracking. (7-1-25)
04. Concrete Septic Tanks. New concrete septic tanks will at a minimum meet the following requirements: (3-31-22)
a. The walls and floor must be at least two and one-half (2 1/2) inches thick if adequately reinforced and at least six (6) inches thick if not reinforced. (3-31-22)
b. The concrete lids or covers must be at least three (3) inches thick and adequately reinforced. (7-1-25)
c. The floor and at least a six (6) inch vertical portion of the walls of a poured tank must be poured at the same time (monolithic pour). (3-31-22)
d. The wall sections poured separately must have interlocking joints on joining edge. (7-1-25)
e. All concrete outlet baffles must be finished with an asphalt or other protective coating. (3-31-22)
05. Horizontal Dimension Limit. No interior horizontal dimension of a septic tank or compartment may be less than two (2) feet. (3-31-22)
06. Liquid Depth. The liquid depth must be at least two and one-half (2 1/2) feet. (7-1-25)
07. Manufactured Tank Markings. Septic tanks manufactured in accordance with a specified design approved by the Director, will be legibly and indelibly marked with the manufacturer’s name or trademark, total liquid capacity, and must indicate the tank’s inlet and outlet. (7-1-25)
08. Minimum Tank Capacities. (3-31-22)
a. Tanks serving single dwelling units. The minimum tank capacity is one thousand (1,000) gallons. For each bedroom over four (4) in a dwelling unit, add two hundred fifty (250) gallons. (7-1-25)
b. Tanks serving all other flows. The minimum tank capacity per structure is one thousand (1,000) gallons or a volume equal to at least two (2) times the maximum daily flow, whichever is greater. (7-1-25)
09. Wastewater Flows from Various Establishments in Gallons per Day.
| ESTABLISHMENTS |
|---|
| DWELLING UNIT |
| ESTABLISHMENTS | |
|---|---|
| Single Family Dwelling, Apartment, Mobile Home, 3 bedroom. Add/subtract 50 gallons per day/bedroom | 250/Unit |
| MULTIPLE RESIDENTIAL | |
| Hotel/Motel: With Private Baths Without Private Baths | 60/Bedspace 40/Bedspace |
| Overnight Accommodation: Central Toilet Central Toilet & Shower | 25/Person 35/Person |
| Rooming House/Bunk House Staff Resident Nonresident | 40/Resident 40/Staff 15/Staff |
| INSTITUTIONAL | |
| Church/Assembly Hall/Meeting House: With Kitchen | 3/Seat 7/Seat |
| Hospital: Kitchen only Laundry only | 250/Bedspace 25/Bedspace 40/Bedspace |
| Nursing Home/Rest Home | 125/Bedspace |
| Day School: Without Showers With Showers With Cafeteria, add Staff-Resident Nonresident | 20/Student 25/Student 3/Student 40/Staff 20/Staff |
| FOOD SERVICE | |
| Conventional Service: Toilet & Kitchen Wastes Kitchen Wastes | 13/Meal 3.3/Meal |
| Take Out or Single Service | 2/Meal |
| Drinking Establishment | 2/Person |
| COMMERCIAL AND INDUSTRIAL | |
| Laundry - Self Service | 50/Wash |
| Service Station | 10/Vehicle |
| Shopping Center (No food/laundry) | 1/Pkg.Sp. |
| Theaters | 5/Seat |
| ESTABLISHMENTS | |
|---|---|
| Offices | 20/Employee |
| Factories: No Showers With Showers Add for Cafeteria | 25/Employee 35/Employee 5/Employee |
| Stores | 2/Employee |
| SEASONAL AND RECREATIONAL | |
| Swimming Pool: Toilet & Shower Wastes | 10/Person |
| Parks & Camps (Day Use): Toilet & Shower Wastes | 15/Person |
| Roadside Rest Area: Toilet & Shower Wastes Toilet Waste | 10/Person 5/Person |
| Designated Camp Area: Toilet & Shower Wastes Toilet Wastes | 90/Space 65/Space |
| Travel Trailer Park with Sewer & Water Hook-up | 125/Space |
| Seasonal/Construction Camp | 50/Person |
| Country Clubs Resident Member Add for Nonresident Member | 100/Member 25/Person |
| Public Restrooms: Toilet Wastes Toilet & Shower Wastes | 5/Person 15/Person |
(7-1-25)
10. Total Volume. The total volume of a septic tank at a minimum must be one hundred fifteen percent (115%) of its liquid capacity. (7-1-25)
11. Inlets. (3-31-22)
a. The inlet into the tank must be at least four (4) inches in diameter and enter the tank three (3) inches above the liquid level. (7-1-25)
b. The inlet of the septic tank and each compartment must be submerged by means of a vented tee or baffle. (7-1-25)
c. Vented tees or baffles must extend above the liquid level seven (7) inches or more but not closer than one (1) inch to the lid of the tank. (7-1-25)
d. Tees must not extend horizontally into the tank beyond two (2) times the diameter of the inlet. (7-1-25)
12. Outlets. (3-31-22)
a. The outlet of the tank must be at least four (4) inches in diameter. (7-1-25)
| Features of Concern | Minimum Distance to Septic Tank in Feet | |
|---|---|---|
| Well or Spring or Suction Line | Public Water | 100 |
| Other | 50 | |
| Water Distribution Line | Public Water | 25 |
| Other | 10 | |
| Permanent or Intermittent Surface Water | 50 | |
| Temporary Surface Water | 25 | |
| Downslope Cut or Scarp | 10 | |
| Dwelling Foundation or Building | 5 | |
| Property Line | 5 | |
| Seasonal High Water Level (Vertically from Top of Tank) | 2 |
(7-1-25)
19. Manufactured Tank Installation. If written installation instructions are provided by the manufacturer of a septic tank, the installer must follow those instructions relative to the stability and integrity of the tank unless otherwise specified in the installation permit. (7-1-25)
20. Inlet and Outlet Piping. Unless otherwise specified in the installation permit, piping material to
and from a septic tank or dosing chamber and to the drainfield must be approved by the Director and specified as follows. (7-1-25)
a. ABS schedule forty (40) piping or material of equal or greater strength. (7-1-25)
b. ASTM D-3034 or equivalent plastic pipe may be used to span the septic tank and dosing chamber if the excavation is compacted with fill material. (7-1-25)
21. Effluent Pipe Separation Distances. Effluent pipes have the same separation distance requirements as septic tanks unless otherwise approved by the Director. (7-1-25)
22. Septic Tank Abandonment. The property owner is responsible for septic tank abandonment and must use the following procedures. (7-1-25)
a. Disconnect the inlet and outlet piping; (7-1-25)
b. Pump the scum and septage with approved disposal; and (7-1-25)
c. Fill the septic tank with earthen materials, physically destroy the septic tank, or remove the septic tank from the ground. (7-1-25)
01. Site Suitability. The area where a standard drainfield will be constructed must meet the following conditions: (7-1-25)
a. The natural slope of the site will not exceed twenty percent (20%). (7-1-25)
b. Suitable soil types will be present at depths corresponding with the sidewalls of the proposed drainfield and at depths between the bottom of the proposed drainfield and any limiting layer (effective soil depth).
| Design Soil Group | Soil Textural Classification | USDA Field Test Textural Classification | |
|---|---|---|---|
| Unsuitable | Gravel | 10 Mesh | |
| Coarse Sand | 10-35 Mesh | Sand | |
| A | Medium Sand | 35-60 Mesh | Sand |
| Fine Sand | 65-140 Mesh | Sand | |
| Loamy Sand | Sand | ||
| B | Very Fine Sand | 140-270 Mesh | Sand |
| Sandy Loam | Sandy Loam | ||
| Very Fine Loamy Sand | Sandy Loam | ||
| Loam | |||
| Silt Loam | Silt Loam | ||
| C | Silt | Silt Loam | |
| Clay Loam | Clay Loam | ||
| Sandy Clay Loam | Clay Loam | ||
| Silty Clay Loam | Clay Loam | ||
| Unsuitable | Sandy Clay | Clay |
| Design Soil Group | Soil Textural Classification | USDA Field Test Textural Classification |
|---|---|---|
| Silty Clay | Clay | |
| Clay | Clay | |
| Clay soils with high shrink/swell potential | Clay | |
| Organic mucks | ||
| Claypan, Duripan, | ||
| Hardpan |
(7-1-25)
c. Effective soil depths, in feet, below the bottom of the drainfield must be equal to or greater than those values listed in the following table.
| EFFECTIVE SOIL DEPTHS | |||
|---|---|---|---|
| Design | Soil | Group | |
| Limiting Layer | A | B | C |
| Impermeable Layer | 4 | 4 | 4 |
| Fractured Bedrock, or Extremely Permeable Material | 6 | 4 | 3 |
| Normal High Groundwater Level | 6 | 4 | 3 |
| Seasonal High Groundwater Level | 1 | 1 | 1 |
(7-1-25)
d. The drainfield must be located so the separation distances are maintained or exceeded according to the following table:
| Feature of Interest | Soil Types All | A | B | C |
|---|---|---|---|---|
| Public Water Supply | 100 | |||
| All wells and Other Domestic Water Supplies | 100 | |||
| Water Distribution Lines: (not double-encased) (double-encased) | 25 10 | |||
| Permanent or Intermittent Surface Water other than Irrigation Canals & Ditches | 200 | 125 | 100 | |
| Temporary Surface Water and Irrigation Canals and Ditches | 50 |
| Feature of Interest | Soil Types All | A | B | C |
|---|---|---|---|---|
| Downslope Cut or Scarp: Impermeable Layer Above Base Impermeable Layer Below Base | 75 50 | 50 25 | 50 25 | |
| Building Foundations: Crawl Space or Slab Basement | 10 20 | |||
| Property Line | 5 |
(7-1-25)
02. Subsurface Disposal Facility Sizing. The size of a subsurface disposal system is determined by the following procedures: (7-1-25)
a. Daily flow estimates are determined in the same manner as flow estimates for septic tank sizing in Subsection 007.08. (7-1-25)
b. Total required absorption area is obtained by dividing the estimated maximum daily flow by a value below or as specified in the TGM.
| Design Soil Group | A | B | C |
|---|---|---|---|
| Absorption Area - Gallons/Square Foot/Day | 1.0 | 0.5 | 0.2 |
(7-1-25)
c. An acceptable site must be large enough to construct two (2) complete drainfields in which each are sized to receive one hundred percent (100%) of the design wastewater flow. (7-1-25)
03. Standard Subsurface Disposal Facility Specifications. Additional design specifications for new subsurface sewage disposal facilities.
| STANDARD SUBSURFACE DISPOSAL FACILITY SPECIFICATIONS | |
|---|---|
| Item | All Soil Groups |
| Length of Individual Distribution Laterals | 100 Feet Maximum |
| Grade of Distribution Laterals and Trench Bottoms | Level |
| Width of Trenches | 1 Foot Minimum 6 Feet Maximum |
| Depth of Trenches | 2 Feet Minimum 4 Feet Maximum |
| Total Square Feet of Trench | 1,500 Sq.ft. Max. |
| Undisturbed Earth Between Trenches | 6 Feet Minimum |
| Undisturbed Earth Between Septic Tank and Trenches | 6 Feet Minimum |
| STANDARD SUBSURFACE DISPOSAL FACILITY SPECIFICATIONS | |
|---|---|
| Item | All Soil Groups |
| Depth of Aggregate: | |
| Total | 12 In. Minimum |
| Over Distribution Laterals | 2 In. Minimum |
| Under Distribution Laterals | 6 In. Minimum |
| Depth of Soil Over Top of Aggregate | 12 In. Minimum |
(7-1-25)
04. Wastewater Distribution. Systems must be installed to maintain equal or serial effluent distribution. (7-1-25)
05. Excavation. Trenches must not be excavated during the period of high soil moisture content when that moisture promotes smearing and soil compaction. (7-1-25)
06. Soil Barrier. The aggregate must be covered throughout with a synthetic filter fabric (geotextile) or other acceptable permeable material. (7-1-25)
07. Aggregate. The trench aggregate must be crushed rock, gravel, or other acceptable, durable and inert material that is free of fines and has an effective diameter from one-half (1/2) to two and one-half (2 1/2) inches. (7-1-25)
08. Impermeable Surface Barrier. A treatment area trench or replacement area may not be: (7-1-25)
a. Compacted. (7-1-25)
b. Covered by an impermeable surface barrier; or (7-1-25)
c. Used for parking or driving on, and must be adequately protected from such activities. (7-1-25)
09. Absorption Bed. Absorption bed disposal facilities may be considered when a site is suitable for a standard subsurface disposal facility except that it is not large enough. (7-1-25)
a. Except as specified in this section, rules applicable to a standard subsurface disposal system apply to an absorption bed facility. (7-1-25)
b. Sites with slopes in excess of eight percent (8%) are not suitable for absorption bed facilities. (7-1-25)
c. Distribution laterals within a bed may not be spaced on greater than six (6) feet centers, and any sidewall may not be more than three (3) feet from a distribution lateral. (7-1-25)
10. Vehicle and Machinery Traffic. Rubber-tired vehicles and machinery may not be driven on the bottom surface of any excavation or on the top of any drainfield. (7-1-25)
11. Failing Subsurface Sewage Disposal System. If the Director determines a system is failing and replacement of the system cannot meet the current rules the replacement system must meet the intent of the rules by using a system design specified by the Director. (7-1-25)
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.
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
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)
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)
01. Technical Allowance. The Director may make a minor technical allowance to the dimensional or construction requirements for a standard system if the allowance: (7-1-25)
a. Does not affect adjacent property owners or the public at large; (7-1-25)
b. Does not violate the intent of the rules. (7-1-25) c. Does not conflict with any other rule, regulation, standard, or ordinance; and (7-1-25) d. Changes to a dimensional requirement is not more than ten percent (10%) unless otherwise provided for in the TGM. (7-1-25)
02. Variance Petition. A petition for rule variance must be filed with the Director and include the following detailed statements describing: (7-1-25)
a. The facts upon which the variance is requested including a description of the intended use of the property, the estimates of the quantity of blackwaste or wastewater to be discharged, and a description of the existing site conditions; (7-1-25) b. The reason petitioner believes that compliance with the provision from which variance is sought would impose an arbitrary or unreasonable hardship, and a list of the injury the variance would impose on the public; and (7-1-25) c. The precise extent of the relief sought. (7-1-25)
03. Public Notice. When filing a petition, evidence must also be submitted showing all property owners within three hundred (300) feet of the affected site were notified fifteen (15) days before filing the petition. (7-1-25)
04. Petition Objections. Any person may file with the Department, within twenty-one (21) days after the filing the petition, a written objection to the grant of the variance. A copy of the objection must be provided by the Department to the petitioner. (7-1-25)
05. Investigation and Decision. After investigating the variance petition and considering the views of persons who might be adversely affected by the grant of the variance, the Director will, within sixty (60) days after the filing of the petition, make a decision regarding the petition. The Department will provide the decision to the petitioner, including: (7-1-25)
a. A description of the efforts made by the Director to investigate the facts as alleged and to obtain and summarize the views of persons who might be affected; (7-1-25) b. A statement of the degree to which, if at all, the Director disagrees with the facts as alleged in the petition; and (7-1-25) c. Allegations of any other facts believed relevant to the disposition of the petition. (7-1-25)
06. Limitations on Decision. No technical allowance or variance will be granted unless: (7-1-25)
a. Adequate proof is shown by the petitioner that compliance would impose an arbitrary or unreasonable hardship; (3-31-22) b. The technical allowance or variance rendered is consistent with the recommendations of the TGC or TGM in use at the time of the petition; and (7-1-25) c. The Director has determined that the approval of the technical allowance or variance will not violate the intent of the rules. (7-1-25)
011. INSPECTIONS.
01. One or More Inspections. The Director will require inspections necessary to determine compliance with any provision of these rules. (7-1-25)
02. Duty to Uncover. The permittee must, at the request of the Director, uncover or make available for inspection any portion or component of a system under construction or covered or concealed in violation of these rules. (7-1-25)
03. Advance Notice by Permittee. If an inspection requires preparation, such as test hole excavation or partial construction of the system, the applicant or permittee must notify the Director at least forty-eight (48) hours in advance, excluding weekends and holidays. (7-1-25)
04. Substantiating Receipts and Delivery Slips. Upon the Director’s request, the permittee must provide copies of receipts, delivery slips, or other similar documents to substantiate the origin, quality, or quantity of materials used in constructing any system. (7-1-25)
05. Finalizing a Permit. No system may receive wastewater until the Director conducts a final installation inspection and completes as-built drawings and specifications depicting the actual installation. The Director will provide a copy of the final as-built drawing to the owner within thirty (30) days after completing the final inspection. (7-1-25)
01. Failure to Comply. All individual and subsurface sewage disposal systems must be constructed and installed according to these rules. Failure by any person to comply with the permitting, licensing, approval, installation, or variance provisions of these rules is a violation of these rules. (7-1-25)
02. System Operation. No person may discharge pollutants into the waters through an individual or subsurface sewage disposal system unless in accordance with the provisions of these rules. (7-1-25)
03. Amendments or Revocations. At any time, the Director may amend or revoke any installation or registration permit or the approval of any system component approved by the Department if: (7-1-25)
a. Approval was based on false or misleading information; (7-1-25)
b. The material, technology, or system no longer achieves performance standards for which it was approved, does not meet the conditions of approval, or does not meet the intent of the rules; or (7-1-25)
c. The permitted installer, service provider, or pumper is not in compliance with or has violated the provisions of these rules (7-1-25)
04. Notice. Except in emergencies, the Department will issue a written notice of intent to revoke to the permittee before final revocation. Revocation becomes final within thirty-five (35) days of the permittee receiving notice unless, within that time, the permittee requests an administrative hearing in writing. The hearing is conducted according to IDAPA 58.01.23, Contested Case Rules and Rules for Protection and Disclosure of Records. (7-1-25)
01. Site Investigation. A site investigation conducted by a soil scientist or hydrogeologist determining whether the LSAS effluent will adversely impact the waters must be submitted to the Director for review and approval. (7-1-25)
02. Installation Permit Plans. Installation permit application plans for an LSAS submitted for approval must include provisions for inspection by the design engineer, designee, or Director of the work during construction. (7-1-25)
03. Module Size. The maximum size of any subsurface sewage disposal module must be ten thousand (10,000) gallons per day. Developments with greater than ten thousand (10,000) gallons per day flow must divide the system into absorption modules designed for ten thousand (10,000) gallons per day or less. (7-1-25)
a. All design elements and application rates must be developed using sound engineering practice and provided by a professional engineer licensed by the state of Idaho. (7-1-25)
b. All design and installation requirements for standard systems apply to LSASs unless otherwise specified in this section. (7-1-25)
c. Within thirty (30) days of completing system installation, the design engineer must provide either as-built plans or a certificate that the system was installed in substantial compliance with the installation permit application plans. (7-1-25)
d. Effective soil depths, in feet, below the bottom of the absorption module to the site conditions must be equal to or greater than the following table:
| EFFECTIVE SOIL DEPTHS | |||
|---|---|---|---|
| Limiting Layer | Design | Soil | Group |
| A | B | C | |
| Impermeable Layer | 8 | 8 | 8 |
| Fractured Bedrock or Extremely Permeable Material | 12 | 8 | 6 |
| Normal High Groundwater Level | 12 | 8 | 6 |
| Seasonal High Groundwater Level | 2 | 2 | 2 |
(7-1-25)
e. The disposal area absorption module must be located so the separation distances provided in the following table, in feet, are maintained or exceeded:
| TABLE -- SEPARATION DISTANCES | |||
|---|---|---|---|
| Feature of Interest | Design | Soil | Group |
| A | B | C | |
| All Domestic Water Supplies | |||
| Sewage Volume - 2,500-5,000 GPD | 250 | 200 | 150 |
| Sewage Volume - 5,000-10,000 GPD | 300 | 250 | 200 |
| Property Lines | |||
| Sewage Volume - 2,500-5,000 GPD | 50 | 50 | 50 |
| Sewage Volume - 5,000-10,000 GPD | 75 | 75 | 75 |
| Building Foundations - Basements | |||
| Sewage Volume - 2,500-5,000 GPD | 50 | 50 | 50 |
| Sewage Volume - 5,000-10,000 GPD | 75 | 75 | 75 |
| Downslope Cut or Scarp | |||
| Impermeable Layer - Below Base | 100 | 50 | 50 |
| TABLE -- SEPARATION DISTANCES | |||
|---|---|---|---|
| Feature of Interest | Design | Soil | Group |
| A | B | C | |
| Separation Distance - Between Modules | 12 | 12 | 12 |
(7-1-25)
05. Monitoring and Reporting. Before an installation permit is issued, the Director will approve a monitoring and reporting plan that contains the following minimum criteria. (7-1-25)
06. Operation and Maintenance. Before an installation permit is issued, an operation and maintenance plan must be approved by the Director and contain the following minimum criteria: (7-1-25)
c. A maintenance entity must be specified to provide continued operation and maintenance according to the operator requirements in IDAPA 58.01.16, Wastewater Rules, and approved by the Director before issuance of an installation permit. The entity may assume the responsibilities of a service provider if a service provider is required. (7-1-25)
All persons, firms, or corporations operating any tank truck or any other device or equipment used or intended for pumping or cleaning septic tanks and transporting or disposing of human excrement, must conform with the following provisions. (7-1-25)
01. Watertight Equipment. The tank or transporting equipment must be watertight and constructed to prevent spilling or leaking while being loaded, transported, or unloaded. (7-1-25)
02. Cleanable Equipment. The tank or transporting equipment must be constructed so that every portion of the interior and exterior can be easily cleaned and maintained in a clean condition at all times while not in use. (7-1-25)
03. Disposal Methods. Disposal of septage from septic tanks must apply the following methods: (7-1-25)
a. Discharge to a public sewer; (7-1-25)
b. Discharge to a sewage treatment plant; or (7-1-25)
c. In a location and by a method approved by the Department. (7-1-25)
04. Permit Application Contents. (7-1-25)
a. All persons operating septic tank pumping equipment must: (7-1-25)
i. Obtain a permit from the Director to operate such equipment; (7-1-25)
ii. Renew permit annually; and (7-1-25)
iii. Apply for permit renewal before March 1 of each year. (7-1-25)
b. The application must be submitted on forms approved by the Director and include: (7-1-25)
i. Number of tank trucks operated by owner; (3-31-22)
ii. Vehicle license number of each tank truck; (3-31-22)
iii. Name and address of owner or operator of equipment; (7-1-25)
iv. Name and address of business, if different from Subsection 051.01.c.; (3-31-22)
v. Methods of disposal to be used in all areas of operation; (3-31-22)
vi. Location of all disposal sites used by applicant; and (7-1-25)
vii. Complete basis of charges made for payment of the work performed. (7-1-25)
05. Permit Fee. All applications must be accompanied by payment of the fee specified in IDAPA 58.01.14, “Rules Governing Fees for Environmental Operating Permits, Licenses, and Inspection Services.” (7-1-25)
06. Vehicle Number Displayed. For each permit issued, a number is assigned to the owner or operator of the tank truck or trucks that must be displayed at all times on the door of the vehicle or vehicles in a legible manner. (7-1-25)
051. -- 995. (RESERVED)
Persons may be entitled to appeal agency actions authorized under these rules pursuant to IDAPA 58.01.23, “Contested Case Rules and Rules for Protection and Disclosure of Records”. (3-31-22)
997. -- 999. (RESERVED)