The Board of Health prohibits the installation of new on-site sewage disposal systems, except as indicated in §
155-86, Exemptions.
All buildings where municipal sewer is available
will be connected to the sewer system upon determination of subsurface
disposal system failure by a licensed system inspector or by order
of the Lexington Board of Health or its agent.
Exemptions to §
155-84 may be allowed under the following conditions:
A. Municipal sewer system is not available to the residence.
Availability of the sewer system will be based on consideration of
the following criteria, including but not limited to: access to the
municipal sewer system, proximity to wetlands, geological characteristics
of the area and easement requirements. If the pipe serving the building
will have to extend more than 30 feet beyond the property line, or
if costs for the sewer line exceed 10% of the assessed value of the
property, the Board of Health will consider alternative proposals
for on-site wastewater disposal for the site.
B. There is no increase in design flow to the system
involved, or the owner can demonstrate that the public health is protected
equally by a new or alternative system with increased design flows,
compared with an older system at previous design flows.
C. The owner can demonstrate manifest injustice caused
by connection to the municipal sewer system compared to the use of
a standard subsurface disposal system or alternative system.
D. Placement of a sewer line conflicts with the state
and Town wetland protection laws or other regulation.
For all inspections of subsurface disposal systems,
a state-licensed inspector shall use the methods noted in 310 CMR
15.00 for seasonal high groundwater determinations. The Board of Health
may, at its discretion, require additional tests to determine seasonal
high groundwater levels.
All disposal systems must be pumped every three
years. All cesspools must be pumped yearly. The septage hauler must
submit to the Board of Health a report of the maintenance service,
including the address at which the service was given, name of system
owner, date and a description of the maintenance services provided.
The Board of Health may allow a variance to
any provisions of these regulations when, in its opinion, the enforcement
thereof would do manifest injustice and the applicant has proved that
the same degree of environmental protection required by these regulations
can be achieved without strict application of the particular provision.
As used in this article, the following terms
shall have the meanings indicated:
ALTERNATIVE SYSTEMS
Systems designed to provide or enhance on-site sewage disposal
systems which either do not contain all of the components of an on-site
disposal system constructed in accordance with 310 CMR 15.000 or which
contain components in addition to those specified in 310 CMR 15.000
and which are proposed to the local approving authority and/or the
Department of Environmental Protection for remedial, pilot, provisional
or general use approval pursuant to 310 CMR 15.280 through 15.289.
BUILDING SEWER
A pipe that begins outside the inner face of a building wall
and extends to an on-site system or municipal or private sewer.
CESSPOOL
A pit with open-jointed linings or holes in the bottom and/or
side walls into which raw sewage is discharged, the liquid portion
of the sewage being disposed of by seeping or leaching into the surrounding
soils, and the solids or sludge being retained in the pit. Cesspools
are nonconforming systems.
DEEP OBSERVATION HOLE
An open pit dug to permit examination of the soils and to
obtain data relative to the mean annual high groundwater elevation.
DISPOSAL SYSTEM INSTALLER
A person, licensed in accordance with 310 CMR 15.019, who
constructs, repairs or replaces an on-site subsurface sewage disposal
system.
DISTRIBUTION BOX
A level, watertight structure that receives septic tank effluent
and distributes it in substantially equal portions to distribution
lines in a soil absorption system.
GROUNDWATER
Water found in cracks, fissures and pore spaces in the saturated
zone below the ground surface, including but not limited to perched
groundwater.
HIGH GROUNDWATER ELEVATION
As determined in accordance with 310 CMR 15.103, 15.104 and
15.107. For inland areas, the elevation above which, in eight out
of 10 consecutive years, the groundwater table does not rise. This
elevation is commonly, but not invariably, reached during the months
of December through April.
MAINTENANCE
All activities required to assure the effective and continuous
operation and performance of an on-site system, including but not
limited to solids and scum removal from the septic tank, re-leveling
the distribution box and the upgrade of one or more of the system
components, all as more fully described in 310 CMR 15.201 through
15.422.
NEW CONSTRUCTION
The construction of a new building for which an occupancy
permit is required or an increase in the actual or design flow to
any nonconforming system or to any other system above the existing
approved capacity. New construction shall not include replacement
or repair of an existing building totally or partially destroyed or
demolished if there is no increase in flow or no increase in flow
above the existing approved capacity for any system.
ON-SITE SEWAGE DISPOSAL SYSTEM or SUBSURFACE DISPOSAL SYSTEM
A system or series of systems for the treatment and disposal
of sanitary sewage below the ground surface on a facility. The standard
components of a system are: a building sewer; a septic tank to retain
solids and scum; a distribution box; a soil absorption system containing
effluent distribution lines to distribute and treat septic tank effluent
prior to discharge to appropriate subsurface soils; and a reserve
area. These terms also include tight tanks, shared systems and alternative
systems. Unless the text of 310 CMR 15.000 indicates otherwise, these
terms also include nonconforming systems.
RESERVE AREA
An area of land with demonstrated capacity for subsurface
sewage disposal on which no permanent structure shall be constructed
and which is intended for siting of a replacement of the principal
system should it fail.
SEPTAGE HAULER
A person licensed by the Lexington Board of Health to remove
septage from on-site sewage disposal systems and transport it to an
approved disposal location in accordance with 310 CMR 15.500.
SEPTIC TANK
A watertight receptacle to receive sewage from a building
sewer which is designed and constructed to permit sufficient retention
of wastewater to allow for the separation of scum and sludge and the
partial digestion of organic matter before discharge of the liquid
portion to a soil absorption system.
SOIL ABSORPTION SYSTEM
A system of trenches, galleries, chambers, pits, fields or
beds together with effluent distribution lines and aggregate which
is installed in appropriate soils to receive effluent from a septic
tank and transmit it to the soil interface for treatment in a biological
mat and disposal to the underlying soils.
WETLAND
Any land area or surface area so defined by the Massachusetts
Wetlands Protection Act, MGL c. 131, § 40, and regulations
promulgated pursuant thereto at 310 CMR 10.00 or pursuant to § 404
of the Federal Water Pollution Control Act, 33 U.S.C. § 1341,
or as defined in the local bylaw.
ZONE II
That area of an aquifer which contributes water to a well
under the most severe pumping and recharge conditions that can realistically
be anticipated, as defined in Massachusetts drinking water regulations,
310 CMR 22.02.