2024 INSTALLER I EXAM WITH
CORRECT ANSWERS
Site Characteristics - CORRECT-ANSWERSexisting structures; slopes; wells;
streams influence system design
Soil Characteristics - CORRECT-ANSWERS40 million bacterial cells in a single
gram of soil Healthy soil is living and breathing and packed with microbes
that breakdown pathogens
Any sewage treatment method has two components: - CORRECT-ANSWERSa
pre-treatment option, such as a septic tank or sand filter, and a dispersal
system, such as a leach field or low-pressure distribution setup.
Pipe from the final treatment tank to a gravity disposal system - CORRECT-
ANSWERSshall be a minimum of 5' in length
Pipe that crosses drainage easements - CORRECT-ANSWERSshall be sleeved
with ASTM Schedule 40 pipe; the pipes shall be buried at least one foot
below the surface, or buried less than one foot and encased with concrete;
the outside pipe shall have locater tape attached to the pipe; and markers
shall be placed at the easement boundaries to indicate the location of the
pipe crossing. Crossings shall be designed and constructed in a manner that
protects the pipe and the drainage way from erosion.
Drainline - CORRECT-ANSWERSThe drainline shall be constructed of
perforated distribution pipe and fittings in compliance with any one of the
following specifications
1) three or four inch diameter PVC pipe with an SDR of 35 or stronger
2)four-inch diameter corrugated polyethylene, ASTM F405 in rigid ten foot
joints
3)three or four inch diameter polyethylene smoothwall, ASTM F810
4)three or four inch diameter PVC ASTM D2729 pipe
5)three or four inch diameter polyethylene ASTM F892 corrugated pipe with
a smoothwall interior and fittings
6) any other pipe approved by the executive director
Drainline installation requirements - CORRECT-ANSWERSThe drainline shall
be placed in the media with a least 6" of media between the bottom of the
excavation and the bottom of the drainline. The drainline shall be completely
covered by the media and the drainline perforations shall be below the
, horizontal center line of the pipe. For excavations greater than four feet in
width, the maximum distance between parallel drainlines shall be four feet
(center to center). Multiple drainlines shall be manifolded together with solid
or perforated pipe. Additionally, the ends of the multiple drainlines opposite
the manifolded end shall either be manifolded together with a solid line,
looped together using a perforated pipe and media, or capped.
Permeable soil barrier - CORRECT-ANSWERSGeotextile fabric shall be used as
the permeable soil barrier and shall be placed between the top of the media
and the excavation backfill.
Geotextile fabric shall conform to the following specifications for unwoven,
spun-bounded polypropylene, polyester, or nylon filter wrap
Pumped effluent drainfield - CORRECT-ANSWERSA)Applicability. If the slope
of the site is greater than 2% pumped effluent drainfields shall not be used.
Pumped effluent drainfields may only be used by single family dwellings.
B) Length of distribution pipe. There shall be at least 1,000 linear feet of
perforated pipe for a two bedroom single family dwelling. For each additional
bedroom, there shall be an additional 400 linear feet of perforated pipe. No
individual distribution line shall exceed 70 feet in length from the header.
C)Excavation width and horizontal separation. The excavated area shall be at
least 6" wide. There shall be at least three feet of separation between
trenches.
D)Lateral depth and vertical separation. All drainfield laterals shall be
between 18" and three feet deep. There shall be a minimum vertical
separation distance of one foot from the bottom of the excavation to a
restrictive horizon, and a minimum vertical separation of two feet from the
bottom of the excavation to groundwater
Restaurant/food establishment sewage - CORRECT-ANSWERSWhen designing
for restaurants, food service establishments, or similar activities, the
minimum design strength value shall be 1,200 mg/1 Biochemical Oxygen
Demand (BOD) after a properly sized grease trap/interceptor. It is the
responsibility of the designer to properly design a system which reduces the
wastewater strenth to 140 mg/1 BOD prior to disposal unless secondary
treatment levels are required.
Other high-strength sewage - CORRECT-ANSWERSFor situations where
sewage as defined in this chapter is expected to be a higher strength than
residential sewage, it is the responsibility of the professional designer to
justify sewage design strength estimations and properly design a system
that reduces the wastewater strength to 140 mg/1 BOD prior to disposal
unless secondary treatment levels are required. Residential sewage is
sewage that has a strength of less than 300 mg/1 BOD
CORRECT ANSWERS
Site Characteristics - CORRECT-ANSWERSexisting structures; slopes; wells;
streams influence system design
Soil Characteristics - CORRECT-ANSWERS40 million bacterial cells in a single
gram of soil Healthy soil is living and breathing and packed with microbes
that breakdown pathogens
Any sewage treatment method has two components: - CORRECT-ANSWERSa
pre-treatment option, such as a septic tank or sand filter, and a dispersal
system, such as a leach field or low-pressure distribution setup.
Pipe from the final treatment tank to a gravity disposal system - CORRECT-
ANSWERSshall be a minimum of 5' in length
Pipe that crosses drainage easements - CORRECT-ANSWERSshall be sleeved
with ASTM Schedule 40 pipe; the pipes shall be buried at least one foot
below the surface, or buried less than one foot and encased with concrete;
the outside pipe shall have locater tape attached to the pipe; and markers
shall be placed at the easement boundaries to indicate the location of the
pipe crossing. Crossings shall be designed and constructed in a manner that
protects the pipe and the drainage way from erosion.
Drainline - CORRECT-ANSWERSThe drainline shall be constructed of
perforated distribution pipe and fittings in compliance with any one of the
following specifications
1) three or four inch diameter PVC pipe with an SDR of 35 or stronger
2)four-inch diameter corrugated polyethylene, ASTM F405 in rigid ten foot
joints
3)three or four inch diameter polyethylene smoothwall, ASTM F810
4)three or four inch diameter PVC ASTM D2729 pipe
5)three or four inch diameter polyethylene ASTM F892 corrugated pipe with
a smoothwall interior and fittings
6) any other pipe approved by the executive director
Drainline installation requirements - CORRECT-ANSWERSThe drainline shall
be placed in the media with a least 6" of media between the bottom of the
excavation and the bottom of the drainline. The drainline shall be completely
covered by the media and the drainline perforations shall be below the
, horizontal center line of the pipe. For excavations greater than four feet in
width, the maximum distance between parallel drainlines shall be four feet
(center to center). Multiple drainlines shall be manifolded together with solid
or perforated pipe. Additionally, the ends of the multiple drainlines opposite
the manifolded end shall either be manifolded together with a solid line,
looped together using a perforated pipe and media, or capped.
Permeable soil barrier - CORRECT-ANSWERSGeotextile fabric shall be used as
the permeable soil barrier and shall be placed between the top of the media
and the excavation backfill.
Geotextile fabric shall conform to the following specifications for unwoven,
spun-bounded polypropylene, polyester, or nylon filter wrap
Pumped effluent drainfield - CORRECT-ANSWERSA)Applicability. If the slope
of the site is greater than 2% pumped effluent drainfields shall not be used.
Pumped effluent drainfields may only be used by single family dwellings.
B) Length of distribution pipe. There shall be at least 1,000 linear feet of
perforated pipe for a two bedroom single family dwelling. For each additional
bedroom, there shall be an additional 400 linear feet of perforated pipe. No
individual distribution line shall exceed 70 feet in length from the header.
C)Excavation width and horizontal separation. The excavated area shall be at
least 6" wide. There shall be at least three feet of separation between
trenches.
D)Lateral depth and vertical separation. All drainfield laterals shall be
between 18" and three feet deep. There shall be a minimum vertical
separation distance of one foot from the bottom of the excavation to a
restrictive horizon, and a minimum vertical separation of two feet from the
bottom of the excavation to groundwater
Restaurant/food establishment sewage - CORRECT-ANSWERSWhen designing
for restaurants, food service establishments, or similar activities, the
minimum design strength value shall be 1,200 mg/1 Biochemical Oxygen
Demand (BOD) after a properly sized grease trap/interceptor. It is the
responsibility of the designer to properly design a system which reduces the
wastewater strenth to 140 mg/1 BOD prior to disposal unless secondary
treatment levels are required.
Other high-strength sewage - CORRECT-ANSWERSFor situations where
sewage as defined in this chapter is expected to be a higher strength than
residential sewage, it is the responsibility of the professional designer to
justify sewage design strength estimations and properly design a system
that reduces the wastewater strength to 140 mg/1 BOD prior to disposal
unless secondary treatment levels are required. Residential sewage is
sewage that has a strength of less than 300 mg/1 BOD
