SEPTIC
SYSTEM QUESTIONS AND ANSWERS – STATE OF MAINE
Septic
System Definitions
List of Questions:
How does a septic system function?
When is a septic system needed?
What regulations cover the design and
installation of septic systems?
Which state or local agencies regulate septic
system?
Do I need to perform a perc test?
What permits are needed
for a septic system?
How do I get a septic system designed
and constructed?
How is a site evaluation performed?
Can I design my own septic system?
Can I build my own septic system?
How do I find an excavating contractor?
Who inspects the installation of the septic
system?
What factors affect the design of the
septic system?
Can I install a drywell for my graywater?
What are the different types of
septic systems?
Why do I need a raised mound?
Can I drive on the septic system?
How do I maintain my septic system?
Are there alternatives to a conventional
septic system?
Is financial assistance available to help
with the cost of my septic system?
SEPTIC SYSTEM QUESTIONS AND ANSWERS
How does a septic system function?
All human structures containing plumbing facilities generate sanitary wastewater
from toilets, sinks, dishwashers, washing machines, and other plumbing fixtures.
A properly operating septic system will treat the wastewater in a septic tank
to remove solid materials and convey the partially treated water into a subsurface
leachfield where it will receive further treatment within the soil before it
is eventually dispersed into the ground. Virtually all the wastewater that enters
a septic system is discharged into the groundwater where it eventually drains
to surface water bodies or groundwater wells, so it is vital that the wastewater
receive adequate treatment in the septic system before it enters the groundwater.
Modern septic systems are designed to provide the necessary treatment; old systems,
while they may make the wastewater go away, do not necessarily provide a high
level of treatment before reaching groundwater.
This site provides additional information on the functioning of septic systems.
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When is a septic system needed?
Any human occupied structure that will have internal plumbing is required to
have a means of disposing of wastewater. Three means of wastewater disposal
are a public sewer, private septic system, or an overboard discharge licensed
by the Maine Department of Environmental Protection. Overboard discharges are
in a special category and are no longer allowed for new developments, meaning
that for any site that is not served by a public sewer, a privately owned septic
tank-leachfield system is necessary.
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What regulations cover the design and installation
of septic systems?
Septic system design in Maine must be done by a licensed site evaluator. The
state regulations covering the state septic system program are 144A CMR 241,
MAINE SUBSURFACE WASTEWATER DISPOSAL RULES. The rules cover details of site
evaluations and design and construction of wastewater disposal systems.
Contractors are not required to be certified in the installation of septic
systems and, in fact, a property owner is entitled to construct their own system.
Maine does have a voluntary certification program for contractors who attend
training sessions covering construction techniques, erosion control, and state
environmental regulations. A list of certified septic system installers can be found here.
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Which state or local agencies regulate septic
system?
The Department of Health and Human Services, Maine Center for Disease Control and Prevention, Division of Environmental Health is the state agency that oversees the administration of the septic system program,
including licensing of site evaluators who design septic systems. The Department
of Environmental Protection does not have jurisdiction over the septic system
program, but the two departments work closely together to resolve pollution
problems caused by malfunctioning septic systems.
The DHE delegates enforcement of the septic system program to individual towns
through the Local Plumbing Inspector, who is licensed by the state to inspect
internal plumbing and septic system construction. Since the LPI is an agent
of the state for septic system issues, property owners need to interact directly
with the LPI to obtain permits and all other septic system issues. The town
may also have a Code Enforcement Officer, who often also serves as the Local
Plumbing Inspector, to enforce other town codes such as shoreland zoning and
building codes.
In unincorporated or unorganized areas of the state the local is done through
the Department of Conservation, Land Use Regulation Commission, who provide
similar services as the municipality. A Local Plumbing Inspector should be available
to issue permits and conduct inspections in unorganized areas.
The Licensed Site Evaluator who designs the septic systems is a private consultant
and is not a representative of a government agency.
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Do I need to perform a “perc” test?
No. Although you may hear the term “perc” or percolation test referred
to in septic system design, the actual test, which consists of filling a hole
with water to determine the soil drainage, is considered obsolete in Maine.
Septic systems are designed by a licensed site evaluator who conducts and site
evaluation which examines all the features of the site including the soil drainage
conditions to determine the best type septic system for the particular site.
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What permits are needed for a septic system?
An external plumbing permit from the Local Plumbing Inspector(LPI) is the generally
the only construction permit needed to construct a septic system. The plumbing
permit consists of the system design on an HHE-200 form with a permit sticker
issued by the LPI. The plumbing permit also covers any state environmental NRPA
permits needed for construction of the project.
Other permits which may be necessary as part of a project done in conjunction
with the septic system are a New or Replacement System Variance(prepared as
part of the plumbing permit application), Minimum Lot Size Variance, Seasonal
Conversion Permit, NRPA Permit, Army Corp of Engineers permit, and internal
plumbing permit. In addition, individual towns may have their own permit requirements
which should be verified locally. The town Code Enforcement Officer should be
contacted for further information.
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How do I get a septic system designed
and constructed?
There are four steps to designing and building a septic system:
1. The system must be designed by a professional known as a Licensed Site Evaluator.
Site Evaluators are private consultants licensed by the State of Maine who charge
a fee for their service. A list of site evaluators who practice locally is available
from the Local Plumbing Inspector of the town where the property is located.
A statewide list of evaluators is also found here. The site evaluator will provide
a system design in a standard format called an HHE-200 form.
2. A permit must be obtained from the Local Plumbing Inspector of the town
where the system will be constructed. Three copies of the system design(HHE-200)
are brought to the Local Plumbing Inspector(LPI) and a permit sticker will be
attached after the permit fee is paid. The LPI will keep two copies of the design
for local and state records, and give one copy back to the applicant. You will
also need to notify the LPI of the schedule for installing the system so that
inspection can be arranged.
3. Construction is normally done by an excavating contractor. It is permissible
to construct the system yourself provided that the installation is done in accordance
with the approved plans. It is recommended that two or more estimates be obtained
from reputable contractors to ensure that the best price is obtained. The cost
of the septic system is influenced by a number of factors including the contractor’s
schedule and source of materials.
4. The system needs to be inspected by the Local Plumbing Inspector to ensure
that it is installed in accordance with the subsurface rules. Inspection of
the system by the designer is not normally provided as a basic service, but
may be available in addition to the design. Because inspections must be coordinated
with the construction schedule, the contractor should be responsible for scheduling
inspections and should be aware of who to contact to do so. The LPI will initial
the HHE-200 when inspections are conducted as evidence that the proper inspections
were performed.
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How is a site evaluation performed?
The site evaluation is performed by a state licensed site evaluator to determine
the appropriate septic system design to handle wastewater on the property. The
site evaluator is a licensed design professional who will charge a fee for this
service. The evaluator will visit the site and examine site characteristics
which affect the design and performance of a septic system. Some of these features
are:
• The size of the property and location of the property lines.
• The location of waterbodies including the ocean, lakes, rivers, streams,
drainage areas, and wetlands.
• Zoning and local ordinances affecting the use of the property.
• Surface drainage patterns.
• Soil conditions on the site.
• The location of existing wells and structures on or adjacent to the
site.
• Steepness of the site.
• The presence of bedrock.
It is the responsibility of the property owner to accurately identify the location
of property lines and easements, and manmade structures such as buildings, wells,
and underground utilities on the site. In addition, the site evaluator will
need to know the nature of the wastewater to be treated in the septic system.
This is often based on the number of bedrooms in the home, and should be carefully
considered since it will affect the size, and cost, of the leachfield, as well
as possibly limiting expansion in the future.
After consideration of all the site conditions, the site evaluator will recommend
the appropriate type of system, or may present alternatives for the property
owner to choose from. In general the system should be located on the downhill
side of the building to allow wastewater to flow by gravity into the system
without the use of a pump.
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Can I design my own septic system?
No. Systems can only be designed by a Maine Licensed Site Evaluator, even for
your own system. In order to obtain a license the evaluators must demonstrate
that they have the ability to properly evaluate site conditions and design a
septic system in compliance with Maine rules and standards.
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Can I build my own septic system?
Individuals may construct their own septic system if they have the capability
to do so. Construction may require the use of heavy equipment and must be built
in accordance with the plans and pass inspections by the Local Plumbing Inspector.
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How do I find an excavating contractor?
Most contractors advertise in the yellow pages, but it is a good idea to obtain
references from other jobs that they may have done. The site evaluator who designs
the system or the Local Plumbing Inspector who issues the permit may have the
names of excavating contractors that they are familiar with.
Maine does not require that contractors be certified or licensed to install
septic systems, but the State does have a voluntary certification program for
contractors. Certification indicates that the contractors have received training
in septic system installation and erosion control techniques. Lists of contractors
certified in septic system installation may be found here. Contractors certified
in erosion control are list here.
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Who inspects the installation of the septic
system?
Septic system inspections are done by the Local Plumbing Inspector of the town
where the system is constructed. The inspector will conduct a minimum of two
inspections, one after the site has been opened and is ready for the installation
of the system, and the second after the system is installed but still uncovered.
The LPI may be willing to conduct additional inspections for a fee.
Inspection is not typically included as part of the design done by the Licensed
Site Evaluator who designed the septic system, but may be negotiated for an
additional fee.
Inspection of the system by the Licensed Site Evaluator who designed it is
not normally provided as a basic service, but may be available as an additional
service.
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What factors affect the design of the septic
system?
The main factors that affect the design of a septic system are the estimated
volume of wastewater flow, the type of soil on the site, and the depth to factors
that affect drainage such as groundwater or bedrock.
The size of the subsurface disposal bed or leachfield is determined by the
estimated volume of wastewater flow and by the soil type where the leachfield
will be constructed. For residences, the flowrate is generally estimated based
on the number of bedrooms and the size of the system is proportional to the
number of bedrooms. The number of bathrooms does not affect the size of the
leachfield. The second factor that affects the size of the leachfield is the
soil type. Depending on the texture and drainage of the soil the leachfield
size of small, medium, large, or extra-large will be determined. These two factors
determine the actual size of the leachfield in square feet. Leachfields are
usually rectangular with long, narrow beds being the best configuration because
they spread the water out more efficiently.
The elevation of the leachfield is determined by the depth to limiting factors
such as groundwater table or bedrock. Limiting factors prevent or impede wastewater
from draining away from the leachfield and the subsurface rules require that
the bottom of the leachfield be raised 12 to 24 inches above the limiting factor.
In addition, this separation between the bottom of the leachfield and the limiting
factor ensures that the waste receives maximum treatment before it enters the
groundwater table. Since the seasonal high groundwater table or depth to ledge
in Maine is frequently found at depths of less than 36 inches, most subsurface
disposal beds are raised up to some extent, and may be mounded up three or four
feet above the original ground on sites that or wet or contain shallow bedrock.
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Can I install a drywell for my graywater?
A drywell is a shallow pit filled with stone or perforated well tile that holds
a volume of water within the well and allows it to trickle out through the sides
of the pit. When used to dispose of wastewater a drywell is also known as a
cesspool or seepage pit. This type of system cannot be legally installed in
Maine because the wastewater does not receive adequate treatment and may pollute
the groundwater.
Separated laundry disposal systems may be used if designed by a licensed site
evaluator. The requirements for a separated laundry system are the same as for
any other wastewater disposal system except that a septic tank is not required
before the leachfield. Because there is no preliminary treatment in a tank,
this type of system is susceptible to plugging due to lint. A separated laundry
system may be an economical alternative to replacing the entire leachfield when
the performance of the septic system is sluggish, but site conditions may prevent
this from being a satisfactory alternative.
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What are the different types of septic
systems?
Septic systems contain two parts:
The septic tank
The subsurface disposal area, or leachfield
The purpose of the septic tank is to remove solids and grease before discharging
partially treated wastewater into the leachfield for further treatment and disposal.
The tank acts as a settling basin and allows heavy solids to settle to the bottom,
and floating material such as grease to rise to the top. The outlet pipe is
placed behind a baffle wall which causes liquid in the tank to be drawn from
the middle rather than the top, preventing the floating scum layer from overflowing
out the effluent pipe. Tanks must be pumped out periodically to remove the solids
and scum which collect to prevent them from washing out of the tank and causing
the leachfield to fail.
Tanks are usually made of concrete, although plastic tanks are available. Plastic
tanks are lightweight and may be carried by two people, but are more easily
damaged than concrete and need to be secured so that they won’t float
when empty. Concrete tanks may be more likely to leak because they contain a
seam between the two halves of the tank. Special one piece tanks are available
when leakage into the tank is critical.
Following treatment in the tank, effluent is discharged into a large subsurface
bed or leachfield. Depending on the elevation of the leachfield it may be necessary
to lift the septic tank effluent into the leachfield with a pump.
The purpose of the leachfield is to distribute the wastewater over a large
area so that it will receive further treatment by soil bacteria before trickling
out into the natural soil and mixing with groundwater. Purification of the wastewater
occurs partially through natural processes from microorganisms living in the
leachfield, and finally be dilution of the final effluent as it seeps into the
groundwater table. In order to protect health the state code requires that the
leachfield be separated from wells and waterbodies to allow natural processes
to fully treat the waste.
The leachfield may consist of a large bed of crushed stone and pipe, or it
may contain manufactured devices that replace the stone and pipe bed. The bed
of stone or other devices create room for the wastewater to be stored until
it trickles away into the soil. Stone beds and proprietary devices serve essentially
the same purpose, and each have benefits.
Benefits of stone beds are:
• There are a “tried and true” technology and have been in
use the longest
• Materials or usually easy to obtain
• May be easier to install
• May be less costly
Benefits of proprietary devices are(Note that there are a wide array of different
proprietary devices and benefits are generalized):
• May use less land area or fill materials
• May be easier to install on certain sites
• Uniform quality of materials
• May be easier to transport
• May be designed for vehicular traffic
• May provide additional treatment of wastewater prior to discharge to
the soil
The specific site conditions are the major consideration for choosing the type
of leachfield materials.
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Why do I need a raised mound?
Septic systems are raised up to improve performance and ensure that complete
treatment of the wastewater occurs before it enters the ground. The State of
Maine Subsurface Wastewater Disposal Rules require that the bottom of a disposal
area be separated from a limiting factor such as the seasonally high groundwater
table or bedrock by 12 to 24 inches. This means that the top of the final grade
over the leachfield will be 36 to 48 inches above the depth to the limiting
factor. The state code allows septic systems to be constructed on soil with
a depth to limiting factor of as little as twelve inches, so raised beds are
not uncommon.
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Can I drive on the septic system?
In general it is not recommended that a system be driven on by cars or heavy
vehicles. Lawns tractors can be used to mow the leachfield without danger. In
cases where there is no alternative it is possible to design a system that will
support traffic. A special heavy duty septic tank, and reinforced concrete leaching
chambers will support traffic without structural damage. Compaction of the soil
under the chambers due to weight and vibration may cause the system to fail
prematurely, however.
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How do I maintain my septic system?
Operation and maintenance of a septic system consists of avoiding or minimizing
the disposal of materials that can shorten the life of the system, and pumping
the septic tank before solids build up too high in the tank.
The following can shorten the system life or impair its performance:
• The use of a garbage disposal is never recommended with a septic system.
Although they are permitted by the state code and special design features can
be added to help minimize their impact, they will most likely shorten the life
of the septic system to some extent.
• Water conservation, including low water use plumbing fixtures, should
be used. Septic systems are designed to handle the water needs of an average
user and may not function properly if excessive volumes of water are used. In
addition, the system will begin to handle less water as it ages. It is prudent
to avoid unnecessary water use with a septic system.
• It is recommended that laundry loads be spread out over more than a
single day if many loads are done to avoid overloading the system. It is also
recommended that liquid rather than powdered laundry detergent be used because
powders contain solid material that can settle out in the septic system.
• Avoid dumping any oil, grease, or fat into the septic system. Although
the septic tank is effective in trapping these wastes if they solidify in the
tank and float to the top, they can quickly clog the soil of the leachfield
if they pass through. Restaurants have historically had septic system problems
due to grease in their waste.
• Do not dump any toxic materials down the drain. This includes chorine
bleach or other cleaners, chemicals, or petroleum products. The septic system
depends on living microorganisms to treat the wastewater before it enters the
groundwater. Materials that are dumped in toxic quantities can result in contaminated
wastewater seeping into the groundwater or even failure of the septic system.
• The use of septic tank additives is not recommended.
Aside from using the system sensibly, the septic tank will need to be pumped
out periodically to avoid accumulated material from washing out into the leachfield.
The actual need for pumping varies depending upon use, but is generally recommended
about every three years. If a garbage grinder is used the tank should be pumped
out every year. Septic tank pumping companies may be able recommend a pumping
interval after pumping the tank, and may send reminders that pumping is due.
Although there is a cost to pump the tank, it is small in comparison to the
cost of a replacement leachfield which could result if pumping is neglected.
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Are there alternatives to a conventional
septic system?
The state plumbing code allows only a few alternatives to conventional septic
systems:
• Separated Laundry system – Laundry waste may be discharged into
a separate leachfield from the rest of the household waste. A treatment tank
is not need for a separated laundry system but the disposal area must still
be designed by a site evaluator. The size of the conventional septic system
may be reduced slightly if a separate laundry system is used, but the use of
separated systems is rare for new construction. A separated system may be an
alternative to help improve the performance of existing septic systems that
are draining sluggishly.
• Alternative toilet – A number of alternative toilets are available,
including composting toilets and pit privies(outhouses). Privies which discharge
to the soil need to be designed by a licensed site evaluator. Alternative toilets
are only intended to handle the black waste, and other household wastewater,
generally called graywater, must still have a conventional system. The state
code does not encourage the use of alternative toilets because there is no provision
to reduce the size of the conventional septic system that handles graywater
only.
• Primitive system – A primitive system consisting of an alternative
toilet and small graywater system may be designed for structures with hand carried
water only, but some town codes do not allow such systems. In general they are
intended for sites which do not have a source of electricity.
• Overboard Discharges – These are small treatment plants that treat
and disinfect wastewater before discharging it to a surface water. They require
a license for the Maine Department of Environmental Protection. They are no
longer allowed for new development but may be permitted for existing properties
that have historically had a discharge and have no viable alternative.
• Drip Irrigation System – This type of system treats the waste
to a high level and then discharges the clean effluent into the soil through
irrigation piping that is buried just below the ground surface. These types
of systems can be costly and their performance during the winter is uncertain.
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Is financial assistance available to help with
the cost of my septic system?
For new construction there is not much financial help other than a conventional
construction loan. For a replacement system the potential alternatives are:
• Home equity loan - If the property owner has sufficient equity in the
property it may be possible to borrow against the value of the house. Home equity
loans will require a mortgage be recorded against the property, and the interest
paid may be tax deductible. Most home equity loans have a variable interest
rate that changes according to the market rates.
• Refinancing – Refinancing the existing mortgage can allow money
to be borrowed over a longer term and at a fixed rate.
• USDA Rural Development 504 Program – This is a federal program
with grants and loans available for home improvements. For information click
here.
• Community Action Program – CAP agencies provide services to low
income families on a county wide basis. They are a potential source of low income
loans. For a list of CAP agencies click here.
• Well and Septic Grants – Some towns in the state, in Aroostook
and Washington Counties, have received federal community development grants
to assist with the construction of replacement wells and septic systems. More
information may be available from the town government.
• DEP Small Community Grant Program – The Maine Department of Environmental
Protection has potential grant funding available to replace septic systems that
are creating a pollution or public health problem. Information is available
here. This funding must be applied for by the municipality.
• Town Loans – A few towns have set up low or moderate interest
loan programs to assist with the construction of septic systems. Information
is available from the town government.
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