2.0 SYSTEM DESIGN
© Presby Environmental, Inc., Design & Installation Manual, July 2020 Edition
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The Remediator may also be placed in a separate tank downstream of the septic tank with a minimum volume of
500 gallons. Illustrated below is the Remediator placed in a 500-gallon Infiltrator IM-540 plastic tank downstream
of the septic tank.
Calculating EnviroFin Units with Aquaworx Remediator
When using a Remediator upstream of an EF field, the number of EF units required is calculated at 150 gpd per
unit. For example: a three-bedroom home = 450 gpd ÷ 150 gpd/unit = 3 units. If the answer is fractional, always
round up to the nearest whole number of units (this assumes residential strength wastewater). Note: Minimum
system sand basal area requirements are not impacted by this change in specifications.
2.8 Site Selection
Determining Site Suitability
Refer to state or local rules regarding site suitability requirements.
Topographic Position Requirement
EF systems shall not be located where surface or ground waters will converge, causing surface water flow to
become concentrated or restricted within the soil absorption field. The system shall be located in an area that does
not concentrate water, both surface and subsurface. If allowed by state and local authorities, altering the terrain
upslope of a system may alleviate this requirement if the waters are sufficiently altered to redirect flows away
from the field.
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Locate systems on convex, hill, slope or level locations. Avoid swales, low areas, or toe-of-slope areas that
may not provide sufficient drainage away from the system.
•
No onsite system may be located on concave slopes that concentrate surface or ground water flows
unless up-slope terrain is sufficiently altered or interceptor drains are used to redirect water away from
the system.
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Systems should not be located where lawn irrigation, roof drains, or natural flows increase water loading
to the soils around the system.
•
Divert surface water away from the system. Interceptor drains, if used, must be upslope and a minimum
of 10 ft away from the EF system and designed to avoid ponding.
•
Systems should not be located where structures such as curbs, walls or foundations might adversely
restrict the soil’s ability to transport water away from the system.
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Systems should be located to allow access for septic tank maintenance and to all FDU’s for effluent removal.
•
Avoid locating systems in rocky or wooded areas that require additional site work, since this may alter the
soil’s ability to accept water.
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No trees or shrubs should be located within 10 ft of the system to prevent root infiltration.
