New Hampshire Septic Installer Exam 2 |
Exam Questions and Correct Answers with
Rationales | System Installation and
Construction
NEW HAMPSHIRE SEPTIC INSTALLER EXAM 2 | SYSTEM INSTALLATION AND
CONSTRUCTION
OVERVIEW
• This document contains comprehensive multiple-choice questions designed to
prepare septic installers for the New Hampshire licensing examination, covering all
critical aspects of system design, installation, and construction standards.
• Study this material by working through questions systematically, reviewing the
detailed rationales for each answer to understand not just what is correct, but
why—this builds both knowledge and practical decision-making skills for field
applications.
SECTION 1: SITE EVALUATION AND SOIL CHARACTERISTICS
1) What is the primary purpose of a percolation test in septic system design?
A) To determine the color of soil in the leach field area
B) To measure how quickly water drains through the soil and establish the soil's
absorption rate
C) To identify underground water sources that might contaminate the system
D) To calculate the depth of the septic tank needed for the property
E) To assess the structural stability of the ground for tank placement
✓ CORRECT ANSWER: B) To measure how quickly water drains through the soil
and establish the soil's absorption rate
,The percolation test is fundamental in septic system design because it directly
determines the soil's ability to absorb effluent. The rate at which water drains—
measured in minutes per inch—establishes how large the leach field must be to
safely handle the volume of wastewater from the home. This information is
essential for calculating the required square footage of absorption area. A slower
percolation rate indicates less permeable soil and requires a larger leach field.
Without this critical measurement, you cannot design a system that meets New
Hampshire regulations or functions properly.
2) In New Hampshire, what is the minimum separation distance required
between a septic system and a private drinking water well?
A) 25 feet
B) 50 feet
C) 75 feet
D) 100 feet
E) 150 feet
✓ CORRECT ANSWER: D) 100 feet
New Hampshire Department of Environmental Services regulations require a
minimum horizontal separation of 100 feet between septic system components
(tank, soil absorption area) and private drinking water wells. This distance is critical
to protect groundwater quality and prevent contamination of the water supply
from failing or leaking septic systems. Different distances apply to other water
sources—wells require 100 feet, surface water requires different setbacks, and
property lines have their own requirements. Understanding these specific distances
is essential for proper site evaluation and design.
3) Which soil type typically has the best absorption characteristics for a septic
system leach field?
A) Clay with high silt content
,B) Sand mixed with gravel in the 0.3 to 3.0 mm range
C) Fine sand with minimal organic matter
D) Dense clay loam
E) Sandy clay with significant fines
✓ CORRECT ANSWER: B) Sand mixed with gravel in the 0.3 to 3.0 mm range
Well-draining sandy soil with appropriate gravel content provides optimal
conditions for septic system leach fields. Soil in the 0.3 to 3.0 mm particle size range
allows water to percolate at a controlled rate—fast enough to prevent surface
ponding, yet slow enough to allow proper treatment. Clay soils drain too slowly and
often fail, while pure fine sand without gravel may create preferential flow paths.
The ideal soil balances infiltration rate with treatment capability, allowing adequate
contact time between effluent and soil bacteria for biological treatment to occur.
4) What does the term "seasonal high water table" mean in the context of
septic system installation?
A) The highest level water reaches during spring flooding
B) The highest elevation that groundwater naturally reaches during the wettest
time of year, typically winter or spring
C) The water level artificially created during system testing
D) The depth at which surface water begins to infiltrate the soil
E) The water level maintained by underground streams
✓ CORRECT ANSWER: B) The highest elevation that groundwater naturally
reaches during the wettest time of year, typically winter or spring
The seasonal high water table is critical in septic design because it represents the
highest level groundwater rises during wet periods—usually winter or early spring
in New Hampshire. New Hampshire regulations require that all septic system
components maintain a minimum vertical separation (typically 2-4 feet depending
on soil type) from the seasonal high water table. If this distance is not maintained,
, the system cannot function properly, treatment is compromised, and groundwater
contamination is likely. Installers must determine this level through soil boring
observations and professional assessment before system design can proceed.
5) Which of the following soil characteristics would require the largest leach
field for a 3-bedroom home in New Hampshire?
A) A percolation rate of 1 minute per inch
B) A percolation rate of 5 minutes per inch
C) A percolation rate of 15 minutes per inch
D) A percolation rate of 30 minutes per inch
E) A percolation rate of 60 minutes per inch
✓ CORRECT ANSWER: E) A percolation rate of 60 minutes per inch
Slower percolation rates require larger leach fields because water moves through
the soil more slowly, meaning more surface area is needed to absorb the daily
wastewater volume. A 60-minute percolation rate indicates very slowly draining soil
(nearly clay-like characteristics). New Hampshire regulations establish specific leach
field sizing requirements based on percolation rate—slower rates require
proportionally larger areas. A home that might need 1,200 square feet with a 5-
minute rate could need 3,000+ square feet with a 60-minute rate. Installers must
calculate these requirements precisely to ensure system adequacy.
6) What is the primary reason for conducting a soil boring during site
evaluation?
A) To extract soil samples for laboratory testing only
B) To determine soil composition, texture, and to identify the seasonal high water
table depth
C) To break through hardpan layers and prepare the site
D) To locate underground utilities
Exam Questions and Correct Answers with
Rationales | System Installation and
Construction
NEW HAMPSHIRE SEPTIC INSTALLER EXAM 2 | SYSTEM INSTALLATION AND
CONSTRUCTION
OVERVIEW
• This document contains comprehensive multiple-choice questions designed to
prepare septic installers for the New Hampshire licensing examination, covering all
critical aspects of system design, installation, and construction standards.
• Study this material by working through questions systematically, reviewing the
detailed rationales for each answer to understand not just what is correct, but
why—this builds both knowledge and practical decision-making skills for field
applications.
SECTION 1: SITE EVALUATION AND SOIL CHARACTERISTICS
1) What is the primary purpose of a percolation test in septic system design?
A) To determine the color of soil in the leach field area
B) To measure how quickly water drains through the soil and establish the soil's
absorption rate
C) To identify underground water sources that might contaminate the system
D) To calculate the depth of the septic tank needed for the property
E) To assess the structural stability of the ground for tank placement
✓ CORRECT ANSWER: B) To measure how quickly water drains through the soil
and establish the soil's absorption rate
,The percolation test is fundamental in septic system design because it directly
determines the soil's ability to absorb effluent. The rate at which water drains—
measured in minutes per inch—establishes how large the leach field must be to
safely handle the volume of wastewater from the home. This information is
essential for calculating the required square footage of absorption area. A slower
percolation rate indicates less permeable soil and requires a larger leach field.
Without this critical measurement, you cannot design a system that meets New
Hampshire regulations or functions properly.
2) In New Hampshire, what is the minimum separation distance required
between a septic system and a private drinking water well?
A) 25 feet
B) 50 feet
C) 75 feet
D) 100 feet
E) 150 feet
✓ CORRECT ANSWER: D) 100 feet
New Hampshire Department of Environmental Services regulations require a
minimum horizontal separation of 100 feet between septic system components
(tank, soil absorption area) and private drinking water wells. This distance is critical
to protect groundwater quality and prevent contamination of the water supply
from failing or leaking septic systems. Different distances apply to other water
sources—wells require 100 feet, surface water requires different setbacks, and
property lines have their own requirements. Understanding these specific distances
is essential for proper site evaluation and design.
3) Which soil type typically has the best absorption characteristics for a septic
system leach field?
A) Clay with high silt content
,B) Sand mixed with gravel in the 0.3 to 3.0 mm range
C) Fine sand with minimal organic matter
D) Dense clay loam
E) Sandy clay with significant fines
✓ CORRECT ANSWER: B) Sand mixed with gravel in the 0.3 to 3.0 mm range
Well-draining sandy soil with appropriate gravel content provides optimal
conditions for septic system leach fields. Soil in the 0.3 to 3.0 mm particle size range
allows water to percolate at a controlled rate—fast enough to prevent surface
ponding, yet slow enough to allow proper treatment. Clay soils drain too slowly and
often fail, while pure fine sand without gravel may create preferential flow paths.
The ideal soil balances infiltration rate with treatment capability, allowing adequate
contact time between effluent and soil bacteria for biological treatment to occur.
4) What does the term "seasonal high water table" mean in the context of
septic system installation?
A) The highest level water reaches during spring flooding
B) The highest elevation that groundwater naturally reaches during the wettest
time of year, typically winter or spring
C) The water level artificially created during system testing
D) The depth at which surface water begins to infiltrate the soil
E) The water level maintained by underground streams
✓ CORRECT ANSWER: B) The highest elevation that groundwater naturally
reaches during the wettest time of year, typically winter or spring
The seasonal high water table is critical in septic design because it represents the
highest level groundwater rises during wet periods—usually winter or early spring
in New Hampshire. New Hampshire regulations require that all septic system
components maintain a minimum vertical separation (typically 2-4 feet depending
on soil type) from the seasonal high water table. If this distance is not maintained,
, the system cannot function properly, treatment is compromised, and groundwater
contamination is likely. Installers must determine this level through soil boring
observations and professional assessment before system design can proceed.
5) Which of the following soil characteristics would require the largest leach
field for a 3-bedroom home in New Hampshire?
A) A percolation rate of 1 minute per inch
B) A percolation rate of 5 minutes per inch
C) A percolation rate of 15 minutes per inch
D) A percolation rate of 30 minutes per inch
E) A percolation rate of 60 minutes per inch
✓ CORRECT ANSWER: E) A percolation rate of 60 minutes per inch
Slower percolation rates require larger leach fields because water moves through
the soil more slowly, meaning more surface area is needed to absorb the daily
wastewater volume. A 60-minute percolation rate indicates very slowly draining soil
(nearly clay-like characteristics). New Hampshire regulations establish specific leach
field sizing requirements based on percolation rate—slower rates require
proportionally larger areas. A home that might need 1,200 square feet with a 5-
minute rate could need 3,000+ square feet with a 60-minute rate. Installers must
calculate these requirements precisely to ensure system adequacy.
6) What is the primary reason for conducting a soil boring during site
evaluation?
A) To extract soil samples for laboratory testing only
B) To determine soil composition, texture, and to identify the seasonal high water
table depth
C) To break through hardpan layers and prepare the site
D) To locate underground utilities
