| Modifications
to Massachusetts Title 5 Code
Approved by the Southborough Board of Health
March 28, 2000
15.223
Septic Tanks
Septic tanks shall have the following capacities:
For a single family dwelling unit, a minimum effective
liquid capacity of 200% of the design flow or a minimum
hydraulic detention flow of 48 hours, whichever is
greater, shall be required. In no case shall the effective
liquid capacity of the tank as measured below the
outlet invert elevation be less than 1,500 gallons.
When designed to serve facilities other than a single
family dwelling unit, and whenever the calculated
design capacity is greater than 330 gallons per day,
a two compartment tank or two tanks in series which
meet(s) the design criteria specified in 310 CMR 15.203
is required. The minimum effective liquid capacity
of each tank in series shall be 200 % of the design
flow. In no case shall the effective liquid capacity
of each tank be less than 1,500 gallons.
Domestic garbage grinders are prohibited.
15.226 Construction of Septic Tanks
(5) All concrete tanks over 2,000 gallons must be
manufactured by a member of either: the NCPA (National
Concrete Products Association), or PCI (Prestressed
Concrete Institute). All manufacturers of tanks (both
concrete and synthetic, fiberglass or plastic) must
supervise the off-loading and installation of all
tanks over 1,500 gallons. The manufacturer must be
responsible for the installation, fabrication and
assembly on-site, and must be responsible for conducting
a vacuum test or water tightness test of each tank;
must schedule with the licensed installer, 48 hours
in advance, for witnessing by the Board of Health
Agent and design engineer and must furnish a certificate
of water tightness.
15.227 Placement and Construction of Tees
(7) All outlet tees shall be fitted with an “outlet
filter” such as Zabel, Orenco, Polylock or Infiltrator,
or equal having an orifice or sieve size such that
no solid larger than .125 inch (1/8”) can pass
through.
REASONS FOR ADOPTING CHANGES TO THE MASSACHUSETTS
TITLE 5 CODE
Septic
Tanks – Two Compartment, and Outlet Filters
(15.223 & 15.227)
The
Board of Health examined documents and literature
provided to it by the Director of Public Health. Several
of theses documents were from manufacturers of two
compartment concrete tanks which have been used extensively
in other states. Much of this literature was gathered
at D.E.P., New England Interstate Water Pollution
Control Commission, and Massachusetts Health Officers
Association conferences and meetings. The literature
convinced the Board Members that a more refined effluent
emanated from tanks, which had two or more compartments,
and outlet filters. Obviously greater amounts of solids
and scum settling took place in two compartment chambers.
Because
of Southborough’s extensive glacial till soils
and the vast surface water supply system (Sudbury
Reservoir) and its numerous tributaries, the Board
is concerned about protecting this valuable asset.
Also, the Board feels that sanitary tee outlet filters
do provide an early warning system to homeowners and
owner operators who neglect to regularly pump their
septic tanks.
Construction
of Septic Tanks (15.226)
The
Director of Public Health attended a session at the
1999 Annual Massachusetts Health Officers Association
Conference and was convinced, after listening to a
presentation made by Mr. Chase, of Chase Pre-Cast
Concrete Co. that better methods for the construction,
placement, and water-tightness of tanks can be assured
by the adoption of the above mentioned regulation.
He provided this literature to the Board of Health
Members who saw fit to vote for its adoption immediately.
In the past, the Board of Health has had problems
with licensed installers attempting to seal large
concrete tanks. They now feel that through the adoption
of this regulation a better system for guaranteeing
water-tightness of tanks can now be more properly
assured.
Modifications
to Massachusetts Title 5 Code
Approved by the Southborough Board of Health - March
11, 2004
Percolation
Testing
Effective January 1, 2004, the Southborough
Board of Health will require at least three (3) percolation
tests in areas with percolation test results greater
than 30 minutes per inch. Additional tests in both
the primary and reserve area shall be required where
soil conditions vary such that the Board or its Agent
are completely satisfied that the entire area within
the soil absorption system percolates between 31 and
60 minutes per inch.
In areas having exposed bedrock outcrops or shallow
to bedrock soils, the Approving Authority may require
as many Deep Observation Test Holes as necessary to
ascertain that the entire proposed S.A.S., including
ten (10) feet outside the S.A.S. in all directions,
have a minimum of four (4) feet of naturally occurring
pervious soils.
Trenches
Soil Absorption Systems (S.A.S.) designed using percolation
rates between 31 minutes and 60 minutes per inch and
for new construction will require the following:
The area between trenches may be designated as system
reserve area only where the separation distance between
the excavation sidewalls of the primary trenches is
at least nine feet.
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