Part IV. Site Limitations
Article 1
Site Limitations
12VAC5-610-591. Overview.
General Criteria for the Selection of a Wastewater Treatment and Disposal System Based on Site Conditions
Article 1
Site Limitations
The intent of this part is to provide guidance on how to match various treatment and dispersal systems to site-specific conditions in order to construct a safe, proper, and adequate sewage system for the site under consideration. Article 1 (12VAC5-610-591 et seq.) identifies site conditions which limit or prohibit the use of onsite systems. Article 2 (12VAC5-610-594 et seq.) establishes criteria for the use of systems that rely on naturally occurring undisturbed soils to treat and disperse effluent, with or without pretreatment. Article 3 (12VAC5-610-597 et seq.) establishes criteria for the use of systems which rely on fill soils to accomplish treatment prior to dispersal.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-592. Setback distances.
A. Septic tanks, other tanks, and header line setback distances. The minimum separation distances between septic tanks, pump chambers, aerobic pretreatment devices (including sand filters, biofilters, and aerobic treatment units), header lines, and similar devices as determined by the department, and various structures and topographic features are contained in Table 4.1 entitled Minimum Separation Distances for Pretreatment Units, Conveyance Lines, and Header Lines.
B. Manifolds. Manifolds shall not pass closer than 50 feet to any drinking water source unless pressure tested in place at pump shut-off head. Under no circumstances shall a manifold come within 10 feet of a drinking water source.
C. Absorption area. The absorption area is the soil medium beginning at the interface between the soil and the gravel, sand, or other point of effluent application, which is utilized for dispersal of the effluent. The absorption area includes the infiltrative surface in the absorption trench, or the point of effluent application, and the soil between and around the effluent distribution system. Setback distance to various structures and topographic features and an absorption area are contained in Table 4.2.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-593. Physical features.
Physical features, landscape position and soil characteristics affect the ability of soil-based systems to treat and disperse effluent. In order to correctly select and place a sewage system in the environment such that public health and the environment are protected, it is necessary to understand and consider the local hydrologic conditions, the regional geology, and the nature of the soils occurring on the site being evaluated. At a minimum, the following features shall be considered:
1. Marshes and swamps. Placement of subsurface soil absorption systems on or in swamps and marshes is prohibited.
2. Seasonal water table. A vertical separation distance between the point of effluent application and a seasonal water table shall be maintained which reflects the quality of the effluent and the receiving environment. Minimum vertical separation distances may be found in Articles 2 (12VAC5-610-594 et seq.) and 3 (12VAC5-610-597 et seq.) of this part and Tables 4.3 and 4.4.
3. Slope. Subsurface soil absorption trench systems shall not be placed on slopes greater than 50% unless terraced. Criteria for other types of onsite systems are contained in Tables 4.3 and 4.4.
4. Drainage ways. Subsurface soil absorption systems shall not be placed at a position in a drainage way subject to intermittent flooding.
5. Fill material. Placement of subsurface soil absorption systems in fill materials is generally prohibited except in three specific situations. The Wisconsin Mound system is considered a fill system as is the sand-on-sand system. These systems are governed by criteria found in 12VAC5-610-960, 12VAC5-610-965, and Table 4.4. Fill material consisting of colluvial soil derived from sandstone (noncarbonaceous) in the mountainous area may be considered on a case-by-case basis for placement of subsurface soil absorption systems.
6. Sink holes. Placement of a subsurface soil absorption system at the low point of a sink hole is prohibited. For set back distance see Table 4.2.
7. Flood plains. Subsurface soil absorption systems shall not be placed in flood plains subject to annual or more frequent sustained (24 hours) flooding.
8. Alluvial and colluvial deposits. Placement of subsurface soil absorption areas in alluvial and colluvial deposits with shallow depths, extended periods of saturation, or possible flooding is prohibited.
9. Shrink-swell soils. When soils containing horizons with shrink-swell characteristics (see definitions in 12VAC5-610-120) have been identified, they shall be rejected for use for subsurface soil absorption systems.
10. Soil restrictions. Soil restrictions in themselves may form the basis for outright rejection of the site.
11. Free standing water. The presence of free standing water in a profile hole may be grounds for rejection of the site.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
Article Art
Icle 2
12VAC5-610-594. In-ground systems.
Article 2
Systems Using Naturally Occurring Undisturbed Soil
A. An in-ground system is a system which utilizes a natural, undisturbed soil horizon to treat and disperse effluent where the infiltrative surface is placed 18 inches or more beneath the original surface of the ground. In-ground systems include, but are not limited to, conventional septic tank drainfield systems, chamber systems, alternative aggregate systems, enhanced flow systems, and pressure dosed systems.
B. Septic tank effluent. Septic tank effluent may be utilized in an in-ground system when all of the site and soil criteria of this subsection are met. Also see Table 4.3.
1. Horizon. The soil horizon(s) for the 18 inches immediately below the installation depth shall not show the presence of any limiting factor. Limiting factors include bedrock, seasonal or permanent water table, pans, or other impervious strata.
2. Separation distances. Table 4.2 contains the minimum setback distances between an absorption field and various structures or topographic features.
3. Estimated or measured infiltration rates. The estimated or measured infiltration rate shall not exceed 120 minutes per inch within any part of the sidewall area of the trench or within 18 inches of the infiltrative interface where effluent encounters undisturbed soil.
C. Soil criteria when utilizing secondary effluent. Secondary effluent may be utilized in an in-ground system when all of the criteria of this subsection are met. Also see Table 4.3.
1. Horizon. The soil horizon(s) for the 12 inches immediately below the installation depth shall not show the presence of any limiting factor. Limiting factors include bedrock, seasonal or permanent water table, pans or other impervious strata.
2. Separation distances. Table 4.2 contains the minimum setback distances between an absorption field and various structures or topographic features.
3. Estimated or measured infiltration rates. The estimated or measured infiltration rate shall not exceed 120 minutes per inch within the sidewall area of the trench, if any, or within 12 inches of the infiltrative interface where effluent encounters undisturbed soil.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-596. Shallow-placed systems.
A. Shallow-placed systems are systems which utilize a natural, undisturbed soil horizon to treat and disperse effluent where the infiltrative surface is placed at a depth of less than 18 inches from the original soil surface. Also see Table 4.3. Shallow-placed systems may use the system designs similar to in-ground systems; however, when shallow-placed systems are installed at less than 12 inches from the ground surface, timed dosing shall be used to disperse the effluent.
B. Septic effluent prohibited. Septic tank effluent is prohibited for use in shallow-placed systems because of the increased likelihood for human and vector contact with effluent.
C. Soil criteria when utilizing secondary effluent. Secondary or better effluent may be utilized in an shallow-placed system when all of the criteria in this subsection are met. Also see Table 4.3.
1. Soil texture. In order to assure effluent dispersal under adverse conditions while maintaining adequate treatment capacity, shallow-placed systems installed shallower than 12 inches, which utilize absorption trenches, are limited to Texture Group I and II soils. Any soil texture group may be utilized for absorption trench systems installed between 12 and 18 inches.
2. Limiting features. A minimum of 12 inches of soil is required beneath the trench bottom or infiltrative surface before encountering soils with a seasonal or permanent water table. Additionally, to assure adequate hydraulic dispersal capacity, bedrock and impervious strata may not occur within 18 inches of the trench bottom.
3. Separation distances. Table 4.2 contains the minimum setback distances between an absorption field and various structures or topographic features.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
Article 3
Systems Using Fill Material
12VAC5-610-597. Fill systems.
Article 3
Systems Using Fill Material
A. Fill systems are systems where the infiltrative surface and some portion of the treatment medium is comprised of fill material and not a naturally occurring undisturbed soil. Fill systems may be located in-ground, shallow-placed, or above ground. Fill systems addressed in these regulations are the Wisconsin Mound system, the noncarbonaceous mountain colluvium system, and the sand-on-sand system.
B. Elevated Sand Mounds. Septic tank effluent may be utilized with elevated sand mounds. Pretreatment shall be required when effluent strength exceeds residential strength wastewater and may be required where hydrologic conditions meet the minimum criteria contained in this chapter. For the purpose of siting an elevated sand mound, the criteria in Table 4.4 shall apply. For the purposes of establishing minimum setback distances between an elevated sand mound and various structures or topographic features, the mound shall be considered an absorption field and distances shown in Table 4.2 utilized.
C. Sand-on-sand systems. Sand-on-sand is a process of modifying a soil absorption system site using fill material which is similar in texture to the original, naturally occurring material. Filling is accomplished in accordance with 12VAC5-610-965.
1. Criteria for utilizing septic effluent. Septic tank effluent may be utilized with sand-on-sand systems. For the purpose of siting a sand-on-sand system, the criteria in Table 4.4 shall apply. Sand-on-sand systems may be utilized with septic tank effluent when the following criteria are met:
a. Soil texture. In order to assure effluent dispersal under adverse conditions, while maintaining adequate treatment capacity, shallow-placed systems are limited to Texture Group I and IIa soils. The use of Texture Group IIb, III and IV soils for sand-on-sand systems is prohibited.
b. Soil structure. Sand-on-sand is restricted to soils classified as entisols (i.e., a young soil with no horizon development) and which have a texture of sand, loamy sand, coarse sandy loam, or sandy loam texture.
c. Depth of soil. A minimum of 18 inches of naturally occurring undisturbed soil, measured from the ground surface, is required before encountering soils with bedrock, or a seasonal or permanent water table. Additionally, to assure adequate hydraulic dispersal capacity, no restrictive horizons may occur within 30 inches of the ground surface.
d. Separation distances. Table 4.2 contains the minimum setback distances between an absorption field and various structures or topographic features.
e. Estimated or measured infiltration rates. When siting a sand-on-sand system, the estimated or measured infiltration rate shall not exceed 30 minutes per inch within the sidewall area of the trench or within 18 inches of the infiltrative interface where effluent encounters undisturbed soil.
f. Slope. Sand-on-sand is prohibited where the slope of the original site exceeds 5%.
2. Criteria for utilizing secondary effluent.
a. Depth of soil. A minimum of 12 inches of soil, measured from the ground surface, is required before encountering bedrock, or a seasonal or permanent water table. Additionally, to assure adequate hydraulic dispersal capacity, no restrictive horizons may occur within 24 inches of the ground surface.
b. Separation distances. Table 4.2 contains the minimum setback distances between an absorption field and various structures or topographic features.
c. Estimated or measured infiltration rates. The estimated or measured infiltration rate shall not exceed 30 minutes per inch within the sidewall area of the trench, if any, or within 18 inches of the infiltrative interface where effluent encounters undisturbed soil.
D. Fill systems in mountain colluvium. The criteria for conventional, in-ground trench systems contained in Table 4.3 shall be complied with to the greatest extent possible. However, fill material consisting of colluvial soil derived from sandstone (noncarbonaceous) in the mountainous area may be considered on a case-by-case basis for placement of subsurface soil absorption systems.
| Table 4.1. | |
| Structure or Topographic Features | Minimum Horizontal Distance |
| Property Lines | 5 |
| Building Foundations | 10 |
| Basements | 20 |
| Drinking Water Wells (all classes) | 50 |
| Cisterns Bottom Elevation Lower than Ground Surface in Area of Pretreatment Unit) | 100 |
| Shellfish Waters | 70 |
| Natural Lakes & Impounded Waters and Streams | 50 |
| Developed Springs (when the spring is down slope) | 100 |
| Drainage Ditches: |
|
| Ditch Bottoms above Seasonal Water Table | 10 |
| Ditch Bottom below Seasonal Water Table and Ditch Normally Contains Water | 50 |
| Lateral Ground Water Movement Interceptor | 50 |
| Low Point of Sink Holes When Placed within the Bowl of the Sink Hole | 100 |
| Utility Lines | 10 |
| Table 4.2. | |||
|
|
| Minimum Distance (Ft) from Bottom or Sidewall of Subsurface Soil Absorption System Trench | |
|
|
| Vertical | Horizontal |
| Property Lines | I, II, III, IV | -- | 5 |
| Building Foundations | I, II, III, IV | -- | 10 |
| Basements | I, II, III, IV | -- | 20 |
| Drinking Water Wells |
|
|
|
| Class IIIA or IIIB | I, II, III, IV | -- | 50 |
| Class IIIC or IV | I, II, III, IV | -- | 100 |
| Cisterns (Bottom Elevation Lower than Ground Surface in Area of Subsurface Soil Absorption System) | I, II, III, IV | -- | 100 |
| Shellfish Waters | I, II, III, IV | -- | 70 |
| Natural Lakes & Impounded Waters | I, II, III, IV | -- | 50 |
| Streams | I, II, III, IV | -- | 50a |
| Developed Springs (when the spring is down slope) | I, II, III, IV | -- | 200e |
| Rock and Rock Outcropping | I | 2 | 2 |
| Rock and Rock Outcropping | II, III, IV | 1.5 | 1.5 |
| Pans and Impervious Strata | I, II, III, IV | 1.5 | 1.5 |
| Drainage Ditches: |
|
|
|
| Ditch Bottoms above Seasonal Water Table | I, II, III, IV | -- | 10 |
| Ditch Bottom below Seasonal Water Table and Ditch Normally Contains Water | I | -- | 70a |
| II | -- | 70a | |
| III | -- | 50a | |
| IV | -- | 50a | |
| Water Table Depressor System | I | 6b | 70 |
| II | 3b | 70 | |
| III | 2b | 50 | |
| IV | 2 | 50 | |
| Lateral Ground Water | I | -- | 70c 10d |
| Movement Interceptor | II | -- | 70c 10d |
| III | -- | 50c 10d | |
| IV | -- | 50c 10d | |
| Low Point of Sink Holes When Placed within the Bowl of the Sink Hole | I, II, III, IV | -- | 100 |
| Utility Lines | I, II, III, IV | -- | 10 |
| aThe set back distance may be reduced to 10 feet in Group III and IV soils and 20 feet in Group I and II soils if the subsurface soil absorption system is designed to produce unsaturated flow condition in the soil. bVertical Distance to the invert of the drain tile in the water table depressor system. cAbsorption trench up slope from interceptor. dAbsorption trench down slope from interceptor. eArc of 180 degree up slope of spring and 100 ft. down slope. | |||
| Table 4.3. | ||||
| Site Factor | In-Ground System1 | Shallow-Placed System1 | ||
| Septic Tank Effluent | Secondary Effluent | Septic Tank Effluent | Secondary Effluent | |
| Bed Rock | 18" | 12" | n/a | 18" |
| Restriction | 18" | 12" | n/a | 18" |
| Shrink-Swell Soil | 18" | 12" | n/a | 18" |
| Slope | 50% | 50% | n/a | 50% |
| Perc Rate | 5-120 mpi | 5-120 mpi | n/a | 5-45 mpi |
| Water Table | 18" | 12" | n/a | 12" |
| 1The separation distances for in-ground and shallow-placed systems are measured from the trench bottom or other infiltrative interface vertically down to listed site factor. | ||||
| Table 4.4. | ||||||
|
| Elevated Sand Mound | Sand-on-Sand System2 | Noncarbonaceous Mountain Colluvium | |||
|
| Septic Tank Effluent | Secondary Effluent | Septic Tank Effluent | Secondary Effluent | Septic Tank Effluent | Secondary Effluent |
| Bed Rock | 24"1 | 24"1 | 60" | 60" | 18" | 12" |
| Restriction | 24" | 12" | 30" | 24" | 18" | 12" |
| Shrink-Swell Soil | 24" | 12" | 40" | 30" | 18" | 12" |
| Slope 25% | 25% | 25% | 5% | 5% | 50% | 50% |
| Perc Rate | 5‑120 mpi | 5‑120 mpi | 5‑30 mpi | 5‑30 mpi | 5‑120 mpi | 5‑120 mpi |
| Water Table | 24" | 10" | 18" | 12" | 18" | 12" |
| 124 inches refers to creviced bedrock. This distance may be reduced to 12 inches when noncreviced bedrock is encountered. See the Wisconsin Mound Soil Absorption System Siting, Design, and Construction Manual, January 1990. | ||||||
| 2The separation distance for sand-on-sand systems is measured from the ground surface vertically down to the listed site factor. | ||||||
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
Article Art
Icle 4
12VAC5-610-598. General.
Article 4
Pump and Haul of Sewage
Pump and haul pertains to an unusual circumstance wherein sewage is permitted to be transported by vehicle to a point of disposal. Pump and haul includes all facilities and appurtenances necessary to collect and store the sewage for handling by a contractor having a valid sewage handling permit.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-599. Permanent pumping and hauling.
Pumping and hauling on a permanent basis is prohibited unless done under the auspices and supervision of a government entity as provided for in 12VAC5-610-599.3 (see subdivision 2 of 12VAC5-610-410 for exception). Pumping and hauling for over one year shall be considered as a permanent pumping and hauling operation.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-599.1. Emergency pumping and hauling.
When serious malfunctioning of an existing sewage disposal system, sewerage system or treatment works occurs, pumping and hauling may be authorized for a definite time period until the malfunctioning system can be reconstructed or repaired.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-599.2. Temporary pumping and hauling.
Temporary pumping and hauling may be permitted under the following conditions:
1. It must be demonstrated that the temporary pumping and hauling of sewage is not the usual practice in order to permit premature and unplanned real estate or commercial development in an area where sewerage facilities do not exist;
2. Construction of an approved sewerage system or treatment works is actively in progress with personnel and machinery at work in the particular area. Bonding, cash escrow or other assurances shall be required to guarantee completion of the sewerage system and/or treatment works;
3. The completion of the sewerage system or treatment works is assured and a completion date within the definition of temporary pumping and hauling has been set; and
4. Any and all delays from the anticipated completion date shall be reported immediately by the holder of the pump and haul permit to the district or local health department. Delays not resulting from circumstances beyond the control of the holder of the pump and haul permit shall be grounds for revocation of the pump and haul permit.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-599.3. Permanent pump and haul.
Permanent pumping and hauling of sewage may be permitted under the following conditions:
1. That the government entity enter into a contract with the department setting forth that the government entity will provide pump and haul services, either directly or through a private contractor holding a sewage handling permit, to the home(s), commercial establishment(s) or occupied structure(s) for the period the occupied structure is utilized or until connection can be made to an approved sewerage facility;
2. Upon completion of the contract between the department and the government entity, the commissioner shall issue a single pump and haul permit to the government entity. A separate construction permit shall be issued to the government entity for each sewage storage facility. The sewage storage facility(s) shall be designed and constructed in accordance with Article 7 (12VAC5-610-990 et seq.) of Part V of this chapter; and
3. When the government entity provides the sewage pump and haul services, it shall conform to the conditions contained in 12VAC5-610-380 and Article 8 (12VAC5-610-1020 et seq.) of Part V of this chapter.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
Article 5
Installation of Residential Sewage Disposal Systems in Political Subdivisions Having Soil Drainage Management Contracts with the State Health Department
12VAC5-610-600. General.
Article 5
Installation of Residential Sewage Disposal Systems in Political Subdivisions Having Soil Drainage Management Contracts with the State Health Department
It is the policy of the department to grant sewage disposal system permits for private residential systems utilizing subsurface soil absorption whenever such permits can be granted without endangering public health. Many soils are limited in their ability to accept sewage by high seasonal water tables. Some soils can accept sewage when an adequate local plan for soil drainage exists. When a political subdivision enters into a Soil Drainage Management Contract with the department and subsequently develops Soil Drainage Management Plan(s) in an area in which soils respond to artificial drainage and the plan is acceptable to the department, the department will consider the approval of subsurface soil absorption systems in soils that were previously unacceptable because of high seasonal water tables.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from VR355-34-02 § 3.16, eff. February 5, 1986; amended, eff. May 11, 1988.
12VAC5-610-610. Definitions.
The following words and terms, when used in this article, shall have the following meanings, unless the context clearly indicates otherwise.
"Soil Drainage Management Contract (SDMC)" means a contract between the department and the political subdivision for the development, operation, maintenance, and enforcement of all soil drainage management plans within the political subdivision.
"Soil Drainage Management Plan (SDMP)" means a plan approved by the commissioner, pursuant to 12VAC5-610-630 below, meeting the criteria set forth in 12VAC5-610-640 below.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from VR355-34-02 § 3.17, eff. February 5, 1986; amended, eff. May 11, 1988.
12VAC5-610-620. Applicability.
This article shall be applicable only in those political subdivisions which enter into Soil Drainage Management Contracts with the department.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from VR355-34-02 § 3.18, eff. February 5, 1986; amended, eff. May 11, 1988; Virginia Register Volume 16, Issue 16, eff. July 1, 2000.
12VAC5-610-630. Procedures for entry into or withdrawal from a Soil Drainage Management Contract (SDMC).
A. Entry.
1. Any political subdivision in the Commonwealth may at any time apply to the department through the district or local health department for entry into an SDMC with the department. The application shall contain the following minimum elements:
a. A proposed contract between the department and the political subdivision; and
b. Drafts of all ordinances, required easements, or other legal documents which the political subdivision proposes to adopt as a portion of the SDMC including a local ordinance requiring the holder of a sewage disposal construction permit issued in conjunction with the SDMC to have the permit recorded in the land records of the circuit court having jurisdiction.
2. The department shall, within 60 days of the submission of an application for entry into an SDMC, evaluate the application and propose to the political subdivision any suggestions for modification to the SDMC.
3. The political subdivision may review the department's suggested modifications and resubmit a revised application within such time as the political subdivision elects.
4. The department shall accept or reject entry into an SDMC within 90 days of receipt of the final application from a political subdivision.
5. Upon rejection by the department of a final application for entry into an SDMC, the political subdivision may appeal the department's decision to the appropriate circuit court. The Virginia Administrative Process Act, § 9-6.14:1, et seq., shall apply to such an appeal.
B. Withdrawal.
1. If the department determines that a political subdivision is failing to abide by the terms set forth in its SDMC with the department, the department may withdraw from the contract.
2. The department shall, within 60 calendar days of its proposed withdrawal from an SDMC notify the political subdivision of the department's intent.
3. The political subdivision may apply to the department for a hearing upon the proposed withdrawal. Such hearing shall be held in accordance with the provisions governing case decisions contained within the Virginia Administrative Process Act.
4. Within 30 calendar days after such hearing, the department shall notify the political subdivision whether the department will withdraw from the SDMC.
5. A decision by the department to withdraw from an SDMC may be appealed to the appropriate circuit court pursuant to the provisions of the Virginia Administrative Process Act.
6. If withdrawal occurs, continued maintenance of all SDMP's shall be the responsibility of the political subdivision in areas where permits were issued in accordance with this chapter.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from VR355-34-02 § 3.19, eff. February 5, 1986; amended, eff. May 11, 1988.
12VAC5-610-640. Minimum standards for Soil Drainage Management Plans.
A. Every SDMP offered in conjunction with a SDMC shall meet the following minimum standards for surface and groundwater management.
B. The SDMP shall provide for:
1. Positive surface grading in the area of a dwelling and subsurface soil absorption area at a minimum of 0.5%;
2. Drainage ditches for diverting surface water and for lowering the seasonal groundwater table which shall:
a. Completely surround the subsurface soil absorption system;
b. Have a minimum grade of 0.2%;
c. Be located 70 feet, ±10 feet from the drainfield; and
d. Have the invert of the ditch placed in a Group I, II or III soil at an elevation so that the normal water surface in the ditch is at least six inches below the invert of the trench of the subsurface soil absorption system;
3. A French drain on one side in lieu of an open drainage ditch on one of the four sides;
4. Diversion ditches or swales shall be:
a. Required where adjacent property is equal to or higher in elevation than the proposed site and the adjacent property may be expected to discharge water onto the proposed site;
b. Designed to meet such site specific individual requirements as the department determines to be necessary;
5. A receiving stormwater and groundwater drainage system which is adequate in capacity so that waters from a proposed site shall be conveyed to it in accordance with the political subdivision's criteria;
6. Diversion ditches, where required, or other ditches to transport stormwater and/or groundwater from a site to a receiving body in accordance with the political subdivision's criteria;
7. Ditches to remain open and not be piped and covered unless approved by appropriate local government official, such approval to be granted only with the concurrence of the department;
8. Only appurtenances to the subsurface soil absorption system shall be constructed within the confines of the perimeter ditches required in paragraph B 2 a, above, except where a French drain is provided on one side; and
9. Lots which shall be a minimum of three acres in size not including swamps or marshland.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from VR355-34-02 § 3.20, eff. February 5, 1986; amended, eff. May 11, 1988.
12VAC5-610-650. Department procedures relating to subsurface soil absorption system applications in SDMC counties and cities.
A. All applications for subsurface soil absorption systems will be evaluated based on the criteria contained in this part. When the site is limited only by a high seasonal water table and/or surface runoff, the department shall require that a satisfactory SDMP be in place and functioning satisfactorily before issuance of a construction permit. Typed on the construction permit will be the following statement which shall be signed by the applicant:
I understand that this soil has severe limitations for the disposal of septic effluent. With the aforementioned drainage measures the health department expects reasonable serviceability, however, it may malfunction during extreme conditions.
I understand and acknowledge the above and agree to install and maintain the drainage measures.
Signed
Date
B. Soils to be considered shall demonstrate their ability to be artificially drained and shall fall generally into Texture Group I, II, or III.
C. The SDMP and site specific drainage system or systems shall be certified, supervised, maintained, and prepared by or under the direct supervision of a professional engineer licensed in Virginia who is a full-time employee of the political subdivision. In addition, the political subdivision shall have the manpower or other capability to maintain the applicable conditions of the SDMP. This certification shall become a part of the subsurface soil absorption system permit.
D. Proper easements shall be provided for drainage to assure access for proper maintenance.
E. Political subdivisions shall assure proper installation and maintenance of the stormwater and ground water drainage system or systems.
F. The department retains the right to reject any SDMP if in the opinion of the department the SDMP proposed will result in a nuisance or health hazard condition.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from VR355-34-02 § 3.21, eff. February 5, 1986; amended, eff. May 11, 1988; Virginia Register Volume 16, Issue 16, eff. July 1, 2000.