How to Install the GreenLeach Filter

General Information These instructions are a guide for the installation of GreenLeach Filter leaching systems, which are manufactured 63 inches wide and are installed with distribution pipe invert heights ranging from 12" to 36" in 3" increments. Unless the experienced, Licensed Installer has been certified by the product manufacturer for unsupervised product installation, a GreenLeach Filter representative must assist with the installation of the system. Prior to starting any septic system, the installer must contact the local health department/district to obtain the proper permits and confirm that you have the most current septic plan. Twenty-four hours prior to the start of any site work, the installer must notify the health department/district and the design engineer, if applicable, that work will be starting. Please note that the GreenLeach Filter leaching system relies upon the use of biodegradable materials so it should be kept sealed and dry until ready to perform the installation. For that reason, it is best to work in dry weather conditions.  

Site Preparation For any septic system installation, it is important to prepare the site in accordance with the approved plans and the CT Public Health Code. GreenLeach Filter systems can be installed in natural soils, totally up in fill, or in some combination of both. It is important that the black organic topsoil layer be removed in the area of the leaching system and at least 5 feet beyond. The trenches must be laid out parallel to existing contours. For all system installations, it is required that washed concrete sand or select fill meeting all specifications listed in the CT Technical Standards be used for both base fill (underneath the filter) and finger backfill material (between the fingers). For the remainder of this document, the terms "washed concrete sand, sand or select fill" means fill material meeting the specifications of the CT Technical Standards for select fill as defined.  

Base Preparation When installed totally in ground, the GreenLeach Filter must be set on a base of at least 6" of washed concrete sand or select fill material. It will be necessary to excavate a trench 7 feet wide and then place 6" of washed concrete sand or select fill in the trench as the base prior to assembly of the product. If installed partially into natural soils or totally above ground in washed concrete sand or select fill, the 6" sand base must meet the requirements for washed concrete sand or select fill. Upon completion of the trench excavation and placement of washed concrete sand or select fill base, the GreenLeach Filter can then be assembled on top of the sand base. The licensed installer is responsible for use and placement of washed concrete sand or select fill beneath and around the leaching system.  

The Product The GreenLeach Filter is an assembly of filter fabric covered cardboard finger components and accessory cardboard or plastic finger spacers, cardboard center/invert spacers, cardboard end plates and preformed cardboard or plastic stone chutes. These components are connected together to create a strong unit structure. The cardboard center spacers are used to connect individual finger side sections together. They also serve to create a 12" wide central stone corridor and support the 4" diameter PVC pipe. The center spacers also serve as the support for the plastic or cardboard chutes, which simply slip into the slots. After treatment of the cardboard fingers with bacterial enzymes to accelerate cardboard decomposition, the structure is now ready for placement of stone and approved septic backfill material. The filter is assembled using five (5) separate pieces - Filter Sides or "fingers" (GL01) which are unfolded to form the leaching fingers, End Plates (GL02) which are placed at the trench ends to contain the stone, End (finger) Braces (GL03) used to maintain the spacing between the individual fingers (used both on the end of fingers and at the core to maintain product tapered shape), the Center Brace (GL05) which holds the two independent sides apart, holds the distribution pipe, creates the center core area and provides for connection of the Chute Brace (GL04) which creates a convenient temporary form to dump the stone into. Note: As an option to use of End Plates, the fabric covered finger product can be overlapped at the trench ends and secured by staples or by use of finger spacers to complete a finished product end.  

Product Assembly Normally, the product is assembled on site by knowledgeable GreenLeach staff that assists the licensed installer with system installation. They or a certified GreenLeach licensed installer begin by opening two or more of the strapped segments in the prepared trench. The fabric covered Filter Sides (GL01) are pre-scored to fold at predetermined lengths. They will form the fingers and must be connected in series by stapling 10-foot segments together. The filter fabric is always located on the external sides to contact the select sand backfill. After connecting two or three Filter Side (GL01) segments together on opposing sides, the filter will now take form as the End (finger) Braces (GL03) are placed to create the tapered fingers. End (finger) Braces (GL03) are also placed at the inside of the fingers close to the Center Brace to create a strong structure and maintain finger spacing. Center Braces (GL 05) are then slipped over the fabric covered Filter Sides (GL 01) approximately 8" apart on each inside finger thereby connecting the two opposing sides together and forming the center core area. It is while placing the center braces that the installer selects one of the three invert heights by removing the preformed perforated cardboard segments to achieve the desired height. Next, install the Chute Brace (GL04), which is used to funnel the stone into the center core and fingers of the filter. Install the End Plate (GL02) or overlap and secure the product finger material at the two ends of the trench. Note that each product provides three options for pipe height and it is important that the distribution pipe be set at the elevation specified on approved plans. With the product assembled and the pipe inverts pre-selected, the perforated pipe can be installed. An enzyme liquid is then sprayed (using a hand pump garden sprayer) on the cardboard side of each finger to promote rapid decomposition of the cardboard. The filter is now ready for placement of three-quarter inch (3/4") (19mm) stone aggregate. For the remainder of this document, three quarter inch (3/4")/ (19mm) stone aggregate means broken or crushed stones, or screened gravel, 0-15% passing a #4 sieve, 90-100% passing a #6 sieve, 90-100% passing a #67 sieve per DOT Section M.01.01, Gradation of Aggregate, free of silt, dirt and debris with abrasion characteristics equal to that of stone aggregate defined in the CT Public Health Code, Technical Standards. The licensed installer is responsible for use and placement of (3/4") stone aggregate inside the GreenLeach form and on top of the distribution pipe.  

Placement of Stone and Sand Slowly dump clean three-quarter inch (3/4") stone aggregate into the cardboard or plastic chute and, using a 2" wide piece of wood or other narrow tool, shift some stone out toward the finger ends. Continue placing stone until the center core is about one third (1/3) full and the fingers have some stone at the ends. Now you can begin to backfill with washed concrete sand or select fill and compact washed concrete sand or select fill on the outside of the filter fingers. The same tool is used for the stone pulling is also used to push the sand between the fingers. Care should be used when filling and compacting with sand in between the fingers on the filter sides. Avoid use of sharp tools that could tear or puncture the fabric. Compact the sand as you go using a narrow weighted tool or the handle of the shovel. Once the sand is up to the same elevation as the stone or slightly higher, you can continue to place more three-quarter inch (3/4") stone aggregate. With some stone on the inside of the form and sand packed on the outside, the finger spacers at the finger ends can be removed to make sand placement easier. It is important that the stone and sand be placed in small lifts to avoid bowing the cardboard out (too much stone) or caving the cardboard in (too much sand). With a little experience (or direction by our staff) and work, the sand and stone components will rise to the desired height. The inside finger spacers can then be removed. When the stone and sand is within 2-4 inches of the top of the filter, the sand spaces should be completely filled to the very top of the cardboard form using a square end shovel. The stone placement chutes can now be removed. Finish the system installation by placing stone the top of the pipe and raking the stone into the fingers with until all the fingers are topped off and the pipe is covered with two inches (2") of stone aggregate. It is OK that the stone covers over the top of the sand filled areas. Installation is almost complete.  

Preparation for Covering After the stone aggregate and washed concrete sand or select fill have been filled to the specified height, and the distribution pipe has the proper stone protection, cover the entire trench with 7 feet wide filter fabric provided by the GLF supplier. Connect the perforated pipe to approved solid distribution pipe continuing to the distribution box or the septic tank. Call the local health department/district and the design engineer (if applicable) for inspection and coordinate/ prepare an as-built drawing to show system location after covered. Upon approval by the regulators and engineer, the system is ready to be covered with six inches (6") minimum of soil.  

Covering the System Care should be used when covering the system with soil. The material should not have any stones larger than two (2") inches in diameter. The top of the distribution pipe and GreenLeach Filter should have a minimum of six (6") inches of soil over it in non-traffic areas. Where the system will be subject to car and truck traffic loading, follow the engineer’s specifications for the required (12" minimum stone/process cover over the pipe) depth of fill cover and proper compaction procedures. All areas should be graded to drain surface water away from the system. All areas should be seeded, mulched or otherwise protected immediately after covering to prevent any erosion on or adjacent to the system.  

Product Guarantee Waste Engineering Inc. will guarantee all GreenLeach Filter systems installed under our staff supervision that meet all the minimum requirements of the CT Public Health Code (Code Complying) for a period of 5 (five) years from the date of installation in accordance with the provisions of the Limited Product Guarantee posted on our website www.greenleach.com. In order for the guarantee to be in effect, the property owner must have in their possession a limited product guarantee document signed by a corporate member.

Installation Instructions last updated 01/01/2009


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