Application of use
The Living Filter product can be used to replace conventional infiltration devices such as, galleries, stone trenches, wrapped pipe, plastic chambers, pipe and stone trenches etc. and can also be used in recirculating sand filters, sand mounds and special construction and FORM CELL BIOREN Systems etc.
The Living Filters when used for simple infiltration into soils, comprises aggregate (inert or synthetic) filled expandable cellular arrays, fully enclosed by a membrane, surrounded by select sand/aggregate and covered by insulation where specified, all meeting the manufacturers specifications.
 

Licensing and Certification
The Living Filter products (in Connecticut) are installed by persons and/or companies licensed and certified by FORM CELL Research, Inc.(FCR)  to perform the installations to FCR specifications (or under the supervision of a FORMCELL representative) in addition to compliance with local, state and applicable regulatory standards as they may pertain.

All installers must be properly licensed by the State of Connecticut, Department of Public Health.    In some jurisdictions, homeowner permits may invalidate the requirement for state licensing,  but would require FCR certification for a one time installation for their residence provided the company is assured their training is adequate to perform the installation.
A register of certified installers is maintained by FCR, Inc., to be shared with the State of Connecticut Department of Public Health, the Department of Environmental Protection and all Connecticut Health Agencies.
 

Living Filter Storage and Handling
The Standard Living Filter is manufactured using biodegradable materials for some components and require dry storage and transport.  The Filters must be kept in a dry location until use.  The installation is preferably done on days without precipitation but can be installed during rainy conditions using some precautions.  If rain develops prior to complete backfilling, it is recommended that the filters be covered by tarps to reduce soaking of the biodegradable forms.
If forms are saturated, not walking on the filters is important or to otherwise disturb the aggregate inside the forms until the exterior is backfilled with sand/aggregate to within a couple of inches of the top.
 

Design Considerations
It is imperative that the site is thoroughly investigated before proceeding to the design phase.  There should be at least two deep test holes in the area of the proposed filter location.  If ledge (rock) is present on the site be sure to confirm adequate separation between ledge and the bottom of filters  at time of installation.  The system must be installed the specified distance above seasonal high groundwater or at least 18 inches above a modified/lowered watertable.  Divert rainwater from filter system location.  If rainwater must traverse the system, the grade should slope at least 5% with no depressions to cause water to enter the system.  Normal installation in soils with a percolation rate faster than 20 minutes per inch requires a minimum of 3 inches of medium/fine sand or aggregate under the filter bottom (*min k=24 ft/day, 100% passing a 1 inch sieve and max 5% passing #200 sieve and/or per manufacturers specifications).  In applications where the percolation rate of underlying soils is slower than 20 minutes per inch a minimum of 6 inches of *sand under the filters is required and if the percolation rate is slower than 30 min/inch a minimum of 12 inches of *sand will be required if the filter effective leaching area per lf exceeds 7.5 sf/lf.  The sand/aggregate` would not be required if naturally occurring materials meet specifications.
 

INSTALLATION

Preparation of Site
Remove all trees at and in the immediate vicinity of the installation.  Tree to system separation should be maintained by cutting trees where the crown of the tree encroach on the installed system unless special barrier materials are placed between the root system of the trees and the filters.  Strip and store all topsoil for reuse.
Remove all roots, stumps and other deleterious materials and remove all organic material under the filters to at least 8 inches outside the footprint of the filters.
 
 
 
 

Erosion Control
Install erosion control where required by local and State Regulations.  Attempt to preserve naturally occurring vegetative filters (low growth, brush and other vegetation).  Install silt fence and/or hay bales.  Grade the area to reduce accumulation and concentrated run off.
 

Excavation for Living Filters
Excavate to desired depth and width as shown on the cross-section part of the installation drawings.
Be sure not to excavate deeper or wider than shown in the drawings.  If the bottom of the trench, in parts,  appear to have soils of lesser permeability than design basis, undercut and fill, mechanically compact with select sand/aggregate to a satisfactory density.  If the depths of low permeability soils exceed 12 inches, contact system designer for guidance.
Be sure to place excavated materials, at least, a minimum of 4 feet from the edge of the trench to prevent overloading of soils and thus reducing the likelihood of cave-ins.
The machine operator while excavating the trench should take special care to remove any projecting large rocks or boulders that could fall and cause injury and damage.
 

Select Sand Placement
Place specified sand/aggregate at bottom of trench up to bottom of filter elevation.  If less than 6 inches hand compact or use mechanical means to achieve a uniform density.  Grade the sand to within .02' +/-.  Working the sand with grading tools will usually achieve adequate compaction.  If sand depths exceed 6 inches use a mechanical vibratory compactor or the equivalent.  Compact in lifts not to exceed 6 inches.  Cover all areas at least twice.  Use your good judgement to assess compaction.  If in doubt, lightly sprinkle with water, run a third pass with the compactor. The grade of the sand bottom for all filters must be level in all directions.  Select sand/aggregate must meet manufacturers' specifications.
 

Install Filters
 1.
Start filter installation by placing the bottom membrane, which will be approximately six inches wider than the filters being placed.  Place roll at one end and unroll for total length.  Leave sufficient membrane at ends of filter row.

2.
Properly align and proceed to install filters.  (If a regeneration pipe [optional] is called for, install according to instructions before the placement of filters).
Expand filters from collapsed storage condition.  Place centered on bottom membrane at 6 inches on center for models LF1210 through LF3610.  Place centered on bottom membrane at 8 inches on center for models LF1226 through LF 3626.
All membrane materials, covering all sides of the Living Filters must meet manufacturer's specifications.
 

3.
Insert special 4 inch perforated corrugated pipe into keyhole slots in the divider walls between cells at spacing specified making sure that the pipe is pressed and seated firmly in the keyhole.  After pipe is in place, align filters to desired position and as shown on the plans.
The pipe, an integral part of the Living Filter, placed inside the units, must meet manufacturer's specifications.
 

4.
Place aggregate chute (approximately 30" wide by 96" +long and at least the width of the bucket) on the filters and proceed to fill with specified aggregate.  Fill to a point where aggregate mounds up about four inches above the top of the Living Filter form.  Move the chute and proceed with the aggregate filling until row is complete.  The aggregate must be clean and free of deleterious materials and meet manufacturer's specifications.
 

5.
Remove chute and cover stone with membrane, proceed to fill with specified sand/aggregate on the exterior of the filters.  Use a tamping tool to compact sand between cells.  Once up to grade, move membrane to one side,  level stone to top of LF form and cover top of filters with membrane overlapping at least 3 inches on both sides of filters.  Make sure that sand/aggregate is adequately compacted between filter cells.  Water may be used to settle the sand further and enhance compaction.  Ensure that there are no sharp protrusions on the compaction tool that could damage the membrane.

6.
Record vertical and horizontal location of all major components of the system before backfilling as follows;  all Living Filter inlet and outlet ends, Distribution Boxes, Septic Tanks, Pump Chambers and all installed pipe including elevation and location at foundation.  If regeneration pipes and monitoring tubes are installed, these should be noted on the record drawings.
Call for inspections by the Health Agency as required, and Engineer if specified.

7.
Where called for, on the plans, cover filters with insulation according to manufacturer's specifications.  Backfill with suitable materials (no stones larger than 2 inches for longest dimension) in non-traffic areas to achieve at least 8 inches of cover over the top of pipe (or as specified on the drawings and per manufacturers specifications).  In traffic areas the minimum cover must be 16 inches of evenly graded structural sand/gravel with appropriate road surfacing for intended loading or as specified by the manufacturer.  If installed under roads and parking in heavily traveled commercial areas, the cross-section must also include one layer of reinforcing fabric placed 8 inches above the top of pipe to at least 36 inches beyond the extremities of the filters or as specified by the manufacturer.  All backfill materials shall contain no stones or particles larger than 2 inches for longest dimension.
It is imperative that no heavy equipment or vehicles are driven over the filter areas in non-traffic areas and that no loading occurs for traffic areas until the full depth of cover (with reinforcing fabric) is installed and the backfill material compacted and stabilized.

Grade so that surface water does not collect over or near the installed system, check to make sure Distribution Boxes are tightly covered to prevent surface water from damaging the system.  Seed and mulch for erosion control.
 
 
 

8.
All filters are set level and are interconnected at the ends by pipe and fittings as specified on the drawings.   Connect the Living Filters to septic tank or other chamber using pipe compliant with State and Local Regulations.  Ensure that slope of pipe entering the first filter has a slope of at least 3/8 inch/lf within four feet of inlet.  If inlet pipe is laid at shallow depth (<12") insulate with at least 2' wide foam insulation (minimum R-5) centered over the pipe.  Although not required by code, it is recommended that insulation be placed over all Pipe, Septic Tanks and Pump Chambers to conserve heat that will aid in the treatment of the effluent.

NOTE:
If the filters are installed under paved or otherwise impervious areas a NITRAP™ filter vent pipe, placed alongside the bottom of the filter, will be required along the portion of Living Filter covered by impervious surfacing.  The filter vent is brought to the surface using Sch.40 PVC of appropriate diameter with a 180 elbow at top sufficiently placed above the ground surface and max. snow height.  The NITRAP filter vent pipe comprise a perforated pipe covered by proprietary fibers.  The effluent delivery conduit present inside the Living Filters is vented through the Septic Tank and Roof Vent as per code, only.
Manufacturers specifications are subject to change without notice, to reflect  changes in design, materials and other improvements made to increase the performance of our products.

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NOTE to Engineers, Designers and Installers:  If Living Filter products rated at over 10.2 sf/lf (effective leaching area) are to be used to meet reserve area requirements, the plans, specifications and site must be reviewed and approved by FORM CELL Research, Inc.

© Copyright, All Rights Reserved, No Duplication, Dissemination or distribution without permission, FORMCELL Research, Inc.,
Kjell E Berg, 1989-2005.  All FORM CELL products are proprietary, patented or patents pending, incorporate trade secrets, trade marks and copyrights. FCR,LF installation manual, 1999-LF1210-LF3626, WP.CTmanual
FORM CELL and LIVING FILTER are registered Trademarks in USA and Sweden. Copyright 1989-2006, All Rights Reserved, FORM CELL Research, Inc., Kjell E. Berg. Patents in the US and the European Union. Pat. Pend. in key countries.Licensing available.