© Presby Environmental, Inc., Maine Design & Installation Manual, June 2019 Edition -28-
38.37 Section / Serial Section
A group of interconnected rows receiving effluent from one distribution box outlet. Sections are limited to 500 GPD
daily design flow maximum.
38.38 Serial Distribution
Two or more pipe rows connected by a Raised Connection. Basic Serial distribution is described in detail in para.
16.0, pg. 12, Combination Serial distribution is described in detail in para. 19.0, pg. 13.
38.39 SHWT
An acronym for
S
easonal
H
igh
W
ater
T
able.
38.40 Skimmer Tabs
Projections into the AES, ES and SS pipe that help to capture grease and suspended solids from the existing effluent
(see illustration in para. 2.0, pg. 3).
38.41 Side-to-Side Configuration
Consist of two or more beds arranged so that the rows are parallel to one another (See para. 22.0, pg. 15 and
illustration on pg. 14).
38.42 Slope (4:1)
In this Manual's illustrations, slope is expressed as a ratio of run to rise. Example: A slope with a grade of (4:1) is the
difference in horizontal distance of four (4) horizontal feet (run) over an elevation difference of one (1) ft. (rise).
38.43 Slope (%)
Expressed as a
percent
, is the difference in elevation divided by the difference in horizontal distance between two
points on the surface of a landform. Example: A site slope of one (1) percent is the difference in elevation of one (1)
foot (rise) over a horizontal distance of one hundred (100) feet (run).
38.44 Smearing
The mechanical sealing of soil air spaces along an excavated, tilled or compressed surface. This is also referred to
as “compacting.” In all installations, it is critical to avoid smearing or compacting the soils under and around the field.
38.45 Surface Diversion
A natural or manmade barrier that changes the course of water flow around an onsite system’s soil absorption field.
38.46 System Sand Bed
System Sand area required/used in systems. The System Sand bed extends a minimum of 6 in. below, 3 in. above
and 6 in. horizontally from the outside edges of the AES or ES pipes.
38.47 System Sand
System Sand must be clean, granular sand free of organic matter and must adhere to the System Sand Specification
with no more than 3% passing the #200 sieve (see complete details in para. 31.0, pg. 18).
38.48 System Sand Extension Area
The System Sand extension area is a minimum of 6 in. deep for Single Level systems (see illustration in para. 23.1,
pg. 16) and 12 in. deep for Multi-Level systems (see illustration in para. 16.0, pg. 12). A System Sand extension area
is required on the down slope side of systems sloping more than 10% and extends a minimum of 3 ft. beyond the
edge of the System Sand (see illustration in para. 23.1, pg. 16).
38.49 Topsoil (a.k.a. Loam or Soil Cover Material)
Topsoil, also known as Loam, is soil material cover capable of sustaining plant growth which forms the topmost layer
of cover material above the system.
38.50 Velocity Reducer
Velocity reducer refers to any of the various components whose purpose is to reduce the velocity of effluent flow into
the pipes. A distribution box with a baffle or inlet tee is sufficient for velocity reduction in most systems (see illustration