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TENNESSEE SEPTIC SYSTEMS
INSTALLATION STUDY GUIDE UPDATED
EXAM WITH VERIFIED SOLUTIONS.
Commissioner - correct answer -No system shall be covered
without the inspection and authorization of the
Conventional Substitute Products - correct answer -A Large
Diameter Gravelless Pipe (LDGP) System is a subsurface
sewage disposal system that has one (1) basic design principle
different from conventional subsurface
sewage disposal systems, which is that an eight (8) or ten (10)
inch inside diameter corrugated polyethylene perforated pipe is
used for the storage and distribution of effluent ni a trenchin lieu
of a four (4) inch diameter pipe and gravel. A filter, fabric wrap
around the pipe prevents soil infiltration into the pipe; and
prevents small,
suspended solids from moving out of the pipe.
LDGP systems exceeding seven hundred fifty (750) gallons of
estimated daily flow volume shall meet the minimum requirements
established in subparagraph (3)(c) of this rule.
Site and Soil Requirements
The site and soil requirements are the same as for a conventional
subsurface sewage disposal system. Where the soil absorption
rate exceeds sixty (60) minutes per inch, gravel backfill, leveled
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with the top of the LDGP, shall be required in accordance with
subparagraphs (4)() and (m) of this rule and a trench width of
twenty-four (24) inches.
.1
(1)
An area of suitable soil must be available equivalent in size to that
necessary to install and duplicate a conventional subsurface
sewage disposal system.
(iii)
The size of the LDGP system shall be determined by the
following:
The suitability of the site shall be determined by a high or extra-
high intensity soil map completed by an approved soil consultant
and other criteria established by these regulations. The soil
absorption rates that range from ten (10) through seventy-five
(75) minutes per inch are acceptable. Soil absorption rates for soil
series and phases of soil series that are established in Appendix I
shall apply. The absorption rates for soil series and phases that
have been recognized by the Natural Resource Conservation
A Chamber System - correct answer -is a media replacement
system consisting of a plastic arch-shaped open bottomed
chamber. Chamber systems that exceed seven hundred fifty
(750) gallons of estimated daily flow volume shall meet the
minimum requirements established in subparagraph (3)(c) of this
rule.
2.
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Site and Soil Requirements
The site and soil requirements are the same as for a conventional
subsurface sewage disposal system.
(11) An area of suitable soil must be available equivalent in size
to that necessary to install and duplicate a conventional
subsurface sewage disposal system.
Layout of the Chamber System
The size of a chamber system shall be equivalent to the total
linear footage required for a three (3) feet wide conventional
subsurface sewage disposal
system. However, where the soil absorption rate is from ten (10)
to sixty (60) minutes per inch, the total linear footage may be
reduced by thirty (30) percent. If a portion of a unit is left over
after determining the total linear
footage required, round up to the nearest whole unit.
The location of the septic tank and the disposal field shall be in
accordance with Rule 0400-48-01-11.
The lateral lines shall be placed on contour. The maximum length
of a single line should not exceed one hundred (100) feet unless
conditions require a longer line.
The trench bottom of each lateral shall have a grade from level to
no greater than two (2) inches per lateral line.
A minimum of six (6) feet of undisturbed earth between adjacent
trench walls shall be required.
Trench width shall be no more than six (6) inches wider than the
product width, with the maximum trench width being thirty-six (36)
inches.
TENNESSEE SEPTIC SYSTEMS
INSTALLATION STUDY GUIDE UPDATED
EXAM WITH VERIFIED SOLUTIONS.
Commissioner - correct answer -No system shall be covered
without the inspection and authorization of the
Conventional Substitute Products - correct answer -A Large
Diameter Gravelless Pipe (LDGP) System is a subsurface
sewage disposal system that has one (1) basic design principle
different from conventional subsurface
sewage disposal systems, which is that an eight (8) or ten (10)
inch inside diameter corrugated polyethylene perforated pipe is
used for the storage and distribution of effluent ni a trenchin lieu
of a four (4) inch diameter pipe and gravel. A filter, fabric wrap
around the pipe prevents soil infiltration into the pipe; and
prevents small,
suspended solids from moving out of the pipe.
LDGP systems exceeding seven hundred fifty (750) gallons of
estimated daily flow volume shall meet the minimum requirements
established in subparagraph (3)(c) of this rule.
Site and Soil Requirements
The site and soil requirements are the same as for a conventional
subsurface sewage disposal system. Where the soil absorption
rate exceeds sixty (60) minutes per inch, gravel backfill, leveled
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with the top of the LDGP, shall be required in accordance with
subparagraphs (4)() and (m) of this rule and a trench width of
twenty-four (24) inches.
.1
(1)
An area of suitable soil must be available equivalent in size to that
necessary to install and duplicate a conventional subsurface
sewage disposal system.
(iii)
The size of the LDGP system shall be determined by the
following:
The suitability of the site shall be determined by a high or extra-
high intensity soil map completed by an approved soil consultant
and other criteria established by these regulations. The soil
absorption rates that range from ten (10) through seventy-five
(75) minutes per inch are acceptable. Soil absorption rates for soil
series and phases of soil series that are established in Appendix I
shall apply. The absorption rates for soil series and phases that
have been recognized by the Natural Resource Conservation
A Chamber System - correct answer -is a media replacement
system consisting of a plastic arch-shaped open bottomed
chamber. Chamber systems that exceed seven hundred fifty
(750) gallons of estimated daily flow volume shall meet the
minimum requirements established in subparagraph (3)(c) of this
rule.
2.
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Site and Soil Requirements
The site and soil requirements are the same as for a conventional
subsurface sewage disposal system.
(11) An area of suitable soil must be available equivalent in size
to that necessary to install and duplicate a conventional
subsurface sewage disposal system.
Layout of the Chamber System
The size of a chamber system shall be equivalent to the total
linear footage required for a three (3) feet wide conventional
subsurface sewage disposal
system. However, where the soil absorption rate is from ten (10)
to sixty (60) minutes per inch, the total linear footage may be
reduced by thirty (30) percent. If a portion of a unit is left over
after determining the total linear
footage required, round up to the nearest whole unit.
The location of the septic tank and the disposal field shall be in
accordance with Rule 0400-48-01-11.
The lateral lines shall be placed on contour. The maximum length
of a single line should not exceed one hundred (100) feet unless
conditions require a longer line.
The trench bottom of each lateral shall have a grade from level to
no greater than two (2) inches per lateral line.
A minimum of six (6) feet of undisturbed earth between adjacent
trench walls shall be required.
Trench width shall be no more than six (6) inches wider than the
product width, with the maximum trench width being thirty-six (36)
inches.
