TN Code § 68-221-403 (2021)
2021 Tennessee Code|Title 68 - Health, Safety and Environmental Protection|Chapter 221 - Water and Sewerage|Part 4 - Subsurface Sewage Disposal Systems|§ 68-221-403. Duties of Commissioner and Department — Permit Approval — Subsurface Sewage Disposal Requirements

  It is the duty of the commissioner to:  Exercise general supervision over the planning, location, construction, operation and maintenance of subsurface sewage disposal systems;   Adopt and promulgate rules and regulations as the commissioner deems necessary to accomplish the purposes of this part, including the adoption of a system of fees for services and permits;   Establish standards for subsurface sewage disposal systems and proposed subdivisions where subsurface sewage disposal systems are to be used;   Enforce this part and rules and regulations promulgated pursuant to this part and make such inspections and investigations as are necessary to determine compliance with the same;   Review and approve the plans and plats of proposed subdivisions;   Issue permits for the installation of subsurface sewage disposal systems. Such permits must be granted or denied within forty-five (45) calendar days of receiving all information necessary to make a determination or the department shall refund the permit processing fee to the permit applicant. The information necessary to make a determination must be communicated to the permit applicant in writing. If the commissioner denies an application, the denial must include a clear, written explanation for the denial with citations to any rules or statutes that were relied on in making the determination;   Issue permits to persons engaging in the business of the construction, alteration, extension or repair of subsurface sewage disposal systems and to persons engaging in the business of removing accumulated waste from such systems;   Suspend or revoke permits issued to persons engaging in the business of construction, alteration, extension or repair of subsurface sewage disposal systems and to persons engaging in the business of removing accumulated waste from such systems, when it is determined that the person has violated this part or applicable rules and regulations;   Require the submission of information in addition to that otherwise required by rules or regulations deemed necessary by the commissioner to determine the suitability of individual lots for subsurface sewage disposal systems; and   Enter into an agreement or contract with county health departments whereby the departments would implement this part or its equivalent in their respective area(s) or jurisdiction. The duty to enter into an agreement or contract shall be mandatory on the commissioner in counties of the first class and the second class which are administering a subsurface sewage disposal program on April 15, 1986, and in other counties the duty to enter into an agreement or contract shall be mandatory for the commissioner when a request is made to the commissioner by the county mayor of such county; provided, that the following conditions shall apply:  State reporting requirements must be met by the county health departments;   The county health department program standards must be at least as stringent as those of the state law and regulations;   The commissioner shall retain the right to exercise oversight and evaluation of performance of the county health departments and to terminate the agreement or contract for cause immediately or otherwise, upon reasonable notice;   The commissioner may set such other fiscal, administrative or program requirements as the commissioner deems necessary to maintain consistency and integrity of the statewide program; and   Staffing and resources must be adequate to implement and enforce the program in the local jurisdictions.       The commissioner may stipulate those parts of the rules, regulations and standards which may be waived for subdivisions containing fewer than five (5) lots.   An applicant for a subsurface sewage disposal permit for a parcel of property may submit to the department the results of a high intensity soils evaluation by a soil scientist certified by the department or the results of percolation tests performed on the property. A permit must be issued to such an applicant for all lots within the parcel which comply with the regulations authorized under subdivision (a)(2) and meet the following requirements:  The results of the percolation test or high intensity soils evaluation must clearly establish that the lot has a percolation rate of:  Not more than one hundred five (105) minutes per inch. The percolation holes used to determine this rate must be located at the intersection of lines in a grid pattern with maximum perpendicular distances of fifty feet (50') between the lines of the grid. Each hole shall be considered reasonably representative of a square area of two thousand five hundred square feet (2,500 sq. ft.) which includes that hole in the approximate center of the square; or   Not less than one hundred six (106) minutes per inch and not more than one hundred twenty (120) minutes per inch; provided, that an alternative method of subsurface sewage disposal is used. The percolation holes used to determine this rate must be located at the intersection of lines in a grid pattern with maximum perpendicular distances of twenty-five feet (25') between the lines of the grid. Each hole shall be considered reasonably representative of a square area of six hundred twenty-five square feet (625 sq. ft.) which includes that hole in the appropriate center of the square;     All percolation tests shall be performed by a soil scientist, engineer, registered professional environmentalist, professional geologist, registered environmental health specialist/registered sanitarian with more than five (5) years experience in a subsurface sewage regulatory program and who has received credentials from the National Environmental Health Association, or surveyor licensed in this state and must be carried out in accordance with the regulations of the department;   The grid pattern referred to in subdivision (c)(1) shall be located within the area to be utilized for the disposal field and reserve area in such a manner as to provide reliable information regarding the percolation rate of the entire area to be utilized for the disposal field and reserve area;   If a percolation test hole within the test grid is unacceptable because the depth to rock is too little, that fact shall not necessarily mean that the remainder of the area within the test grid is unacceptable, only that the area represented by that particular hole is unacceptable;   The department shall report the actual average percolation rate, as determined by the percolation test, on the subsurface sewage disposal system permit. The actual average percolation rate shall be determined by averaging only the test results from the area actually to be covered by the permit;   The disposal field shall contain a minimum of three hundred seventy square feet (370 sq. ft.) of trench bottom area per bedroom; and   When a permit applicant intends to rely upon the results of percolation tests, the applicant shall not be required to perform a high intensity soils evaluation of the area proposed for the subsurface sewage disposal system. However, for proposed subdivisions, the applicant shall submit a plat showing the results of a soils evaluation performed by a soil scientist certified by the department, the sole purpose of which is to determine which portions, if any, of the area proposed for the disposal field and reserve area are unsuitable for percolation tests because of depth to rock, slope or water problems. For individual lots which are not part of a subdivision, the general soils evaluation described in the preceding sentence is not required, but an evaluation of the lot may be performed by an employee of the department without preparing a plat. The percolation tests used to determine the actual average percolation rate of the area to be used for the disposal field and reserve area shall be run after the submission of the general soils evaluation, and the department shall be notified at least three (3) days prior to the day that these tests will be run. If the general soils evaluation concludes that a particular area is unsuitable for percolation tests, the applicant may then perform a high-intensity soils evaluation of that area to gather additional information which may show that the area is suitable for percolation tests. When a proposed area is determined to be unsuitable for percolation tests, that area may be further evaluated to determine its suitability for an alternative subsurface sewage disposal system, and where found appropriate, shall be approved by the department for an alternative system.     Permits for the construction of subsurface sewage disposal systems shall be issued for single family residence lots in subdivisions which were approved by the local health authority prior to April 15, 1986, in accordance with the following requirements:  Permits for lots within subdivisions approved prior to July 10, 1974, shall be based upon soils or percolation data, where such data are available for the recorded plat of the subdivision, and systems shall be constructed in accordance with the requirements authorized by subdivisions (a)(2) and (3), except for those provisions dealing with duplicate area and slope;   Permits for lots with subdivisions approved July 10, 1974, or after, shall be based upon soils or percolation data, where such data are available for the recorded plat of the subdivision, and systems shall be constructed in accordance with the requirements authorized by subdivisions (a)(2) and (3);   In the absence of any data on file or on the recorded plat, permits shall be issued and systems constructed in accordance with the requirements authorized by subdivisions (a)(2) and (3), except those provisions dealing with duplicate area and slope. The disposal field for these systems shall contain at least three hundred seventy square feet (370 sq. ft.) of trench bottom area per bedroom; or, if the lot does not have sufficient area to install this amount, the maximum square footage that can be installed; provided, that an absolute minimum of two hundred square feet (200 sq. ft.) per bedroom must be installed. The permit shall note that the system is for an approved subdivision without adequate available soils or percolation data; and   The eighteen inch (18") requirement of subsection (f) does not apply to systems approved under this subsection (d), or to subdivisions approved by the commissioner prior to July 1, 1990.      In the adoption and promulgation of rules and regulations under this section, the standards for subsurface sewerage disposal systems shall, in counties with a population of not less than twelve thousand three hundred fifty (12,350) nor more than twelve thousand four hundred (12,400), according to the 1970 federal census or any subsequent federal census, provide that the media for the disposal fields shall consist of crushed rock or gravel varying in size from three-fourths inch (¾") to two and one-half inches (2½"); or of creek gravel; or of other material authorized for substitution by the county sanitation officer.   In the adoption and promulgation of rules and regulations under this section, the standards for subsurface sewage disposal systems shall, in counties with a population of not less than six thousand (6,000) nor more than six thousand one hundred twenty-five (6,125), and in counties with a population of not less than nine thousand six hundred fifty (9,650) nor more than nine thousand seven hundred fifty (9,750), if approved by a two-thirds (2/3) vote of the legislative body of such county before September 6, 1983, all according to the 1980 federal census or any subsequent federal census, provide that the media for the disposal fields shall consist of crushed rock or gravel varying in size from three-fourths inch (¾") to two and one-half inches (2½"); or of creek gravel; or of other material authorized for substitution by the county sanitation officer.     It is permissible to use blasting to remove unwanted rock in order to install a septic tank or a solid line leading to the tank or from the tank to the disposal field. Where blasting is used in the construction of the disposal field, no section of pipe designed to let, or capable of letting, water escape through perforations, joints, or any other opening shall be located within ten feet (10') horizontally of rock which has been blasted, and an anti-seep collar shall be installed at the junction of the perforated pipe and a solid pipe passing through the zone of blasted rock in such a manner as to prevent sewage discharged from perforations in the perforated pipe from moving laterally from the perforated pipe toward the blasted rock. In addition to the other requirements contained in the regulations, in no case shall any section of pipe designed to let, or capable of letting, water escape through perforations, joints, or any other opening be located within eighteen inches (18") (at least twelve inches (12") shall be undisturbed soil) vertically of rock in the area of karst geology (however the department may specify a lesser distance in a non-karst area) or within three feet (3') horizontally of rock which has not been blasted. This subsection (f) is applicable to all subsurface sewage disposal system permits issued by the commissioner.    Where the undisturbed soil layer above rock is between eighteen inches (18") and twenty-four inches (24") deep, a low pressure pipe system may be installed; provided, that no portion of any seepage trench (i.e., aggregate-encased-perforated pipe) is within three feet (3') horizontally of rock which has not been blasted and ten feet (10') horizontally of rock which has been blasted. The elevation of each perforated distribution pipe in the low pressure pipe system shall be the same as the elevation of the natural soil in the vicinity of each pipe. Each perforated pipe shall be installed on a bed of aggregate located in a trench excavated six inches (6") wide and six inches (6") deep into undisturbed natural soil. Each perforated pipe shall be covered by two inches (2") of aggregate. Each seepage trench shall be separated five feet (5') horizontally and covered with at least twelve inches (12") of compatible soil; provided, that all vegetation is removed from the original soil surface and it is plowed to a depth of three inches (3") with a chisel plow prior to the placement of the added soil. The covering soil shall extend, at a minimum depth of twelve inches (12"), for a distance of five feet (5') beyond the perimeter of the area containing the seepage trenches and then taper to natural soil level with a maximum side slope for the covering soil of three (3) to one (1) (i.e., three feet (3') horizontal to one foot (1') vertical). At least five (5) observation tubes shall be provided by installing fourteen inch (14") long sections of one and one half inch (1.5") diameter pipe that will extend from the natural soil surface to above the surface of the covering soil. The location of the observation tubes will be specified for each system by a soil scientist certified by the department.   Before any system may be approved under this subsection (g), a soils evaluation must be made by a soil scientist certified by the department, and the department must find that the soil is sufficiently permeable to allow proper absorption of the sewage into the soil. To the extent they are not inconsistent with this subsection (g), the general regulations governing low pressure pipe systems are applicable to systems installed pursuant to this subsection (g).   Any system approved under this subsection (g) shall be identified on a restrictive covenant filed with the local register of deeds for the property served by the system.     Recognizing the acute need for environmentally safe and economically feasible on-site wastewater disposal systems for sites with marginal soil resources, and further recognizing the potential for development of numerous satisfactory designs, the department is charged to continually strive to identify and/or develop design and operating criteria for systems that have potential for functioning properly on sites with limited soil depth above a limiting horizon (e.g., fragipan, perched water table, rock).   When the undisturbed soil layer above rock is between twenty-four inches (24") and thirty-six inches (36") deep, a conventional disposal system may be installed, if the following requirements are met:  The depth of gravel in the trench shall be either eight inches (8"), ten inches (10") or twelve inches (12") with a minimum depth underneath the pipe of three inches (3") and with a minimum depth above the pipe of one inch (1"). As the depth of gravel is reduced to ten inches (10") or eight inches (8"), the length of the trenches will increase proportionately such that the total cubic footage and the infiltrative surface on the side wall of the trenches will remain constant;   The original soil surface shall be at least seven inches (7") above the top of the gravel in the trench;   There shall be at least nine inches (9") of undisturbed soil between the trench bottom and rock;   The disposal field area shall have at least ten inches (10") of backfill above the elevation of the gravel in the trench. A maximum of three inches (3") of the backfill may be compatible soil fill; provided, that all vegetation is removed from the original soil surface and it is plowed to a depth of three inches (3") with a plow prior to the placement of the added soil. The covering soil shall extend, at the required depth, for a distance of five feet (5') beyond the perimeter of the area containing the seepage trenches and then taper to natural soil level with a slope for the covering soil of three feet (3') horizontal to one foot (1') vertical or flatter; and   The eighteen inch (18") requirement of subsection (f) does not apply to systems approved under this subsection (i). To the extent they are not inconsistent with this subsection (i), the general regulations governing conventional disposal systems are applicable to systems installed pursuant to this subsection (i).     In addition to the department's authorization for systems which have gained the approval of the National Sanitation Foundation, the department shall also authorize the use of not more than fifty (50) units of any system which meets the National Sanitation Foundation Standard 40 conducted by a research I institution that has an accredited civil and environmental engineering program; provided, that the applicant for any such unit shall, in addition to all other fees prescribed, pay to the department a special inspection fee of one hundred dollars ($100).   Permits shall be issued for the repair of any system in existence prior to July 1, 1990, pursuant to statutes, rules and regulations in effect on June 30, 1990.   The commissioner shall use a portion of the fees imposed and collected pursuant to state law to fund a position in the division of ground water protection. The person filling this position shall perform the following tasks:  Determine the number of lots approved by the local health authority and/or the commissioner prior to July 1, 1990, in at least ten (10) counties in this state, which counties shall be selected by the department as representative of counties which have the greatest need for alternative subsurface sewage disposal systems;   Gather and compile all readily available information, from other states and from throughout this state, concerning all alternative subsurface sewage disposal systems which might feasibly be used in this state, and make this information available to members of the public; and   Communicate on a regular basis with members of the public concerning the availability, cost, environmental advantages, and other factors relevant to alternative subsurface sewage disposal systems.