Onsite wastewater treatment and dewatering systems

Abstract

A drainage product has at least one conveyance component having at least one outlet, and at least one aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned in relation to the drainfield conveyance component in at least one orientation selected from: attached to, placed adjacent to or beneath or on top of or inside or commingled in some iteration of the conveyance component, or adjacent the outlet of the conveyance component, or between two conveyance components, to provide an improved drainfield for a sewage disposal and dewatering systems.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to onsite wastewater treatment and dewatering systems. While the discussion below primarily addresses wastewater treatment systems, the principles of the invention also apply to dewatering systems generally. What has been shown and described is a drainage product which provides improved protection and strength for the distribution or conveyance medium,

2. Description of the Related Art

Onsite wastewater treatment systems (OWTS) are usually deployed in suburban or rural areas that are not connected to municipal or city sewer systems. The OWTS is comprised of two primary components called the septic tank and the drain field. This waste stream is typically provided by a single family residence, but could easily be provided by commercial constructs such as a restaurant or office complex.

The septic tank can be constructed from a variety of materials. The current state of the art tanks are produced from concrete, plastic, or fiberglass. They are manufactured to be structurally sound and to withstand the harsh conditions and exposure to waste water. The tanks capacity or size is usually determined by the size of the house in accordance with local ordinances. The minimum size of a septic tank is typically 1000 gallons. Often these tanks have internal baffles that provided individual compartments. These compartments facilitate the management of the liquid, solid and scum movement in the tank.

The functionality of the septic tank is described as the primary treatment of raw sewage. The liquid effluent enters the tank transporting both solids and debris. The primary purpose of the septic tank is to clarify the wastewater and to provide primary treatment for the sewage. Clarification means that constituents that float and sink are separated from the wastewater stream by settling in the bottom of the tank. The liquid or effluent is then transported to the next treatment component. In addition the septic tank begins the decomposition of the organic material or treatment phase. It reduces raw waste to sludge, scum, gases, and clarified liquid effluent, and it does this by raising beneficial microbes that reduce the organic material without outside energy sources. Simply, it works just like a fermentation vessel works to make wine or beer. A septic tank is the preferred method of the primary treatment and clarification of raw sewage without regard to the down stream treatment components.

As the liquid effluent exits the septic tank, it can be transported by gravity or mechanically to the next level of treatment. In this discussion, we will focus on a gravity fed system that employs the soil as the secondary remediation device. This does not preclude drain fields from use after a secondary treatment device, but the parameters for in ground dispersal following a treatment device are different by state codes.

The second component of a septic system after the tank is the conveyance component or drainfield. Often, the term drainfield is interchangeable with nitrification field or lines, in ground dispersal field, subsurface dispersal systems, and field lines. The most common and most frequently installed method of building a drainfield uses gravel, rock, or crushed stone as a porous media and a 4 inch diameter perforated pipe in a below grade trench typically one to three feet wide and twelve inches deep. The length and overall depth is determined by local ordinance. Gravel is placed in the bottom of the trench to a depth of 6 inches and the corrugated pipe is placed on top of the gravel in the center of the trench. The remainder of the trench and the pipe are covered with six more inches of gravel for a total height of 12 inches. Effluent enters the distribution pipe from the septic tank. The effluent then migrates through the gravel to arrive at the trench bottom. Once the trench bottom is covered with effluent, then the side walls of the trench further facilitate exfiltration into the soil. The soil then performs the remediation of the effluent and returns the clean water to the ground water supply.

This method of drainfield design has been around for at least 100 years. The evolution and design were primarily developed through trial and error. Currently, this method, in an evolved design, is utilized in every state. Failure rates for using this type of system range from 10 to 40%. Generally, this design is considered viable and the standard. The inherent disadvantages of gravel were then examined and newer methods were developed to eliminate them.

Gravel disadvantages include:

• It is a non-renewable resource, so supplies are limited and its cost is rising,
• Gravel is dense (heavy) and it requires energy to make, transport, and place it,
• Labor costs are high.
• Site impact is negative from the heavy equipment and stray pieces of stone.
• Gravel for septic system use must be washed and cleaned. Even after cleaning the stones, the fines or dust levels in gravel are significant. The level of fines adversely impacts the flow characteristics of gravel.

A number of alternative systems evolved as a result of these gravel disadvantages. The first alternative product to arrive in the on site industry was a ten inch diameter plastic corrugated and perforated pipe with a geotextile fabric “sock” surrounding it. Often referred to as Large Diameter Pipe, it is available now in 6, 8 and 10 inch diameters. The second product to be used in the onsite industry was the plastic chamber. The chamber is a hollow dome that has an open bottom and louvered sidewalls. This product is advertised as the most popular alternative product.

Other types of products include alternative or cleaner aggregates. Shredded or recycled Tire chips are typically given to contractors for use in place of traditional aggregates. The loose chips are scattered in the trench to replace the function of stone. Another aggregate product that is the number two alternative product used is contained polystyrene aggregate with an integral pipe. This product is a true replacement for stone. It is a clean, light-weight contained aggregate with the distribution pipe enclosed.

The last alternative product that is relevant here, is the product called multi-pipe. Multi-pipe is a special arrangement of perforated pipes that when bound together provide void space for storage of effluent and a tortuous path for presentment to the infiltrative surface.

These products are described in further detail later. The drainfield receives clarified effluent from the septic tank via a piping network referred to as a header, which provides the pathway for the effluent to the drainfield. The header then attempts to equally divide the liquid to a number of trenches. There are devices that split the flow more precisely, but they do not impact the drainfield function or design. Often, the number of trenches equals three or more. For all drainfields and products used in the trenches, the trenches are prepared the same and the plumbing of the header is similar. The purpose of the drainfield is to deliver effluent to the soil for remediation and to store effluent during a surge event. The soil performs the remediation and its ability to perform this function is independent of the delivery device. So, the idea is to maximize the surface area of the trench to receive effluent and to provide a product that will utilize that available area by designing the product to maximize the interface architecture.

As the remediation process occurs in the soil, a layer of biologic slime or biomat develops on the bottom and sides of the trench or anywhere that effluent is allowed to accumulate. The stored effluent inhibits the transfer of oxygen to the biologics that facilitates the degradation. As the biomat develops, it forms a resistance layer to the flow of effluent out of the trench. Some of the biomat grows into the soil forming a large resistor and diminishes flow. Aqueous biomat stays suspended above the soil surface providing minimal resistance to flow. Combining the varying resistances from products, biomat, and soil, the effluent flow can be slowed to a trickle out of the trench. Therefore, it is desirable to reduce or eliminate the resistance contribution due to subsurface disposal systems.

Drainfield products are sold by the linear foot or trench foot. Often, products are rated as providing a specific number of infiltrative square feet per linear feet of product. A three foot wide by twelve inch deep gravel trench has 3 SF/LF of bottom infiltrative surface area. Gravel is the standard that other products are then compared against. This provides the variable necessary to calculate the overall required trench length. The quantity of dirt excavated and the drainfield product selected to fill the excavation depends upon the trench length and width. Thus, the amount of excavation and the amount of drainfield product contribute to the total cost of the onsite system. Consequently, drainfield products compete for product ratings that are higher than gravel and other alternative products. Historically, alternative products receive ratings that are higher than gravel which allows the provider to excavate less soil and install less drainage product. One might think that more linear feet of product sold returns more profits to the manufacturers and installers, however, the contrary is true. Longer alternative product trenches are cost prohibitive when compared with gravel. That is, alternative products are competitive with gravel trenches when the total length of alternative trench is significantly less than with gravel. Economics dictate that success for alternative products is driven by the volume of systems installed rather than comparison on an individual basis.

Understanding the function, sizing and economics of drainfields, we can proceed with a more detailed description of drainfield products.

Large diameter pipe (LDP) is typically sized with a one to one relationship to gravel trenches. That is, for every foot of gravel trench required, one foot of LDP is installed. The excavation width can be less than three feet and the length is equal to that of a gravel filled trench. LDP utilizes the perforated pipe to wet the geotextile fabric sock and the sock acts like a wick. The wick is then completely saturated (wetted) and once saturated it then presents the effluent along the entire perimeter of the pipe to the soil. This has been beneficial for the LDP manufacturers. They are permitted to place a single pipe in the ground that occupies ⅓ of the width occupied by a gravel filled trench. Currently, regulations are moving toward making LDP fill a trench completely with three pipes or tripling the length of the trenches required. LDP manufacturers are fighting this change, but their efforts are falling on deaf ears. The product may be rendered obsolete by regulation if LDP does not modify their product. However, adding two more pipes to the trench or adding ⅔'s more trench length to an onsite system that is currently priced equivalent to gravel may be economically unfeasible.

Other problems associated with LDP are the surrounding filter fabric and the ability of the pipe to deliver effluent to the soil. The filter fabric works just like any other filter. It removes debris from the effluent (inside the pipe). The fabric also prevents debris from any potential influent source (outside the pipe) from entering the pipe. Eventually, the filter fabric clogs and once it clogs, the system may fail.

Chamber systems have risen to the top of the list as an alternative product to gravel. Chambers are manufactured in a variety of sizes. They vary in width and height from 12 to 34 inches. Chambers are also sold by the linear foot and come in 6 to 10 foot lengths. Their cost is dependant upon the width of the product and the weight of the plastic used to make the chamber. Chamber manufacturers claim superior performance or better delivery of effluent to the soil. They have promoted a reduced trench length because of their “superior performance” and have been successful in convincing the regulatory community of the same. If chambers were required to provide a one to one relationship with gravel, the cost might prohibit them from participating in the market.

Chambers are basically a barrel vault with louvered sides. The six to ten foot length panels attach end to end to one another to fill the trench. End panels are placed at the beginning and end of the trench. The effluent from the septic tank flows through the header pipe and connects to a pipe inlet in the endplate. The open bottom of the chamber allows the effluent to strike the soil for the entire length of the chamber. When the biomat forms on the trench bottom and retards the flow, the effluent escapes through the side louvers.

Chambers are manufactured in a variety of sizes. The sides are corrugated, perforated, or zig-zagged. All of these iterations are attempts to get more effluent out of the “box” and into the soil. Another reason for the variety of designs in the sidewalls is the infiltration of soils into the chamber. The chamber acts as a mold for infiltrating soil. With the chamber removed, the completely filled imprint remains. Some chambers have attempted to thwart the infiltration of soil into the chamber by adding a barrier fabric to cover the chamber louvers. Regulations are pushing toward the wider and heavier chamber for use in the industry. More product material, even at reduced lengths means more cost. If regulations for a three foot wide trench become the accepted standard, then smaller width chamber (15 inch) models may be eliminated unless there is an adaptation.

A replacement for stone aggregate (gravel) has been exemplified in the product called EZflow by RING Companies (Houck Drainage System): placing clean polystyrene aggregate around a 4 inch corrugated and perforated pipe and packaging it all in a net. Further, they make aggregate bundles to fill the void space adjacent to their pipe and to alter the architecture in the trench. This product can be configured horizontally, vertically, and triangularly. In any case, all configurations are covered with an untreated craft building paper. EZflow comes in 10 foot lengths and is very flexible. The clean aggregate provides more void space than gravel and the product is free of fines that further reduce or retard flow into the soil. EZflow uses polystyrene for the aggregate or bead composition. The bead or aggregate shape is given some consideration by the patent office for what is essentially the letter E. One regulatory authority refers to the bead as the “Double E”.

The EZflow product depends upon the inclusion of the aggregate bundles to support the encased pipe. When the product compresses under a static soil load, the void volume of the product diminishes and the flow characteristics are altered. The Houck Drainage System, EZflow teaches toward concentric pipes and aggregate bundles in a variety of configurations.

Another product to be considered is called multi-pipe. It is essentially the combination of the frequently used plastic four inch corrugated and perforated pipe. The perforations alternate with circular holes and linear slits in the successive lengths of pipe. The pipes are prepackaged into bundles of 6, 9, 11, and 13. Each of the combinations or iterations changes the architecture or presentation in the trench. The entire bundle is often wrapped with a geotextile fabric to prevent the intrusion of soil into the system.

The effluent enters the pipes and leaks effluent into the trench. As it migrates to the bottom of the trench, the effluent then percolates into the soil. Once the clogging mat or biomat forms on the inside of the geotextile fabric, the filter may “plug” and the system fails.

Two other combination patented products that are currently not sold, are termed “aggregate chambers” U.S. Pat. No. 6,443,652 and “liquid leaching field” U.S. Pat. No. 6,705,800. They are essentially the same product. They have two aggregate bundles and a plastic cover to form a chamber-like product with aggregate sides. The cost of this unit renders it unfeasible to manufacturer and sell.

BRIEF SUMMARY OF THE INVENTION

A novel drainage product that comprises at least one conveyance component having at least one outlet, and at least one aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned in relation to at least one infiltration or exfiltration conveyance component in at least one orientation selected from: attached to, placed adjacent to or beneath or on top of or inside or fastened to at least one conveyance component, or adjacent to said at least one outlet of said at least one infiltration or exfiltration component, or between two light weight aggregate components, to provide an improved wastewater drainfield for a sewage disposal system or to improve dewatering and storm water runoff systems by providing alternative trench architecture and interface design.

These and other features and advantages are evident from the following description of the present invention, with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a section through a typical prior art drainfield structure;

FIG. 2 is a perspective view of a large diameter pipe drainfield component;

FIG. 3 is a section through another prior art drainfield structure;

FIG. 4 is a section through a drainfield structure in accordance with one form of the invention;

FIG. 5 is a partial perspective view of a two forms of a drain board type of foundation drain component;

FIG. 6 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 7 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 8 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 9 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 10 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 11 is a set of sections through several forms of aggregate bundle in accordance with the invention;

FIG. 12 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 13 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 14 is a section through drainfield structure in accordance with another form of the invention;

FIG. 15 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 16 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 17 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 18 is a section through a drainfield structure in accordance with another form of the invention;

FIG. 19 is a section through a drainfield structure in accordance with another form of the invention; and

FIG. 20 is a section through a drainfield structure in accordance with another form of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention utilizes light weight aggregate bundles that are combined with existing drainage products and this combination presents a completely new functioning system. The trench architecture or presentation in the trench is altered to conform to EPA or governing authority regulations. The use of the invention renders otherwise obsolete products viable.

In accordance with one form of the invention, a contained light weight aggregate bundle comprised of an aggregate is contained within a geotechnical material (netting) that when added to an existing product becomes a system in and of itself. In effect, the invention permits a combination of existing products like large diameter pipe, chambers, multi-pipe, and the single 4 inch pipe with a contained synthetic aggregate bundle. The light weight contained aggregate bundle is affixed or positioned adjacent to or inside an existing product either in the field or as a complete unit provided by the manufacturer.

Below is a description of how these existing products could be combined with the invention components. The invention is the variable that alters or adapts an existing product for use or continued use in the drainage industry.

Large Diameter Pipe

Removal of the geotextile fabric from LDP and adding one or two synthetic aggregate bundles in accordance with the invention to either side of the pipe yields a new system. This new system has additional infiltration area since the product is wider. The removal of the geo fabric eliminates the plugging described earlier. Additional storage volume for the system is achieved and the protection of the exit holes of the LDP pipe by the clean synthetic aggregate bundles. Further, placing a synthetic aggregate bundle of smaller diameter in the interior of the LDP, will act as a floatation device that artificially increases the pressure head and thus the driving force of liquid out of the LDP. The economics of such a system are viable. The LDP pipe product could continue use with the invention.

Small width Chamber

Small width chambers are existing products that will fall by the wayside if the current regulatory efforts are successful. The small width chamber is horizontally challenged and the vented louvers on the sides present a fill hazard for the chamber. Adding two synthetic aggregate bundles to the sides of the chamber will protect the louvers from dirt infiltration and change the trench architecture. The invention allows for use of the lower cost smaller chamber and provides for greater infiltrative surface area. Also, adding a small diameter synthetic aggregate bundle inside the chamber will help to increase the head pressure by occupying void volume and thus driving effluent into the soil. This new system is cost effective and could be commercially viable.

Below is a description of how these existing products could be combined with the invention components. The invention is the variable that alters or adapts an existing product for use or continued use in the drainage industry.

The technical concepts are the same with larger chambers. In fact, smaller diameter synthetic aggregate bundles of circular or irregular shapes could be placed along the sides of the louvers to protect them from infiltration and one or more synthetic aggregate bundles could be placed inside the chamber to increase head effects. Simply stated, the invention added to chamber products improves the functionality and benefits of the existing product.

Multi-Pipe

Utilizing the multi-pipe product with synthetic aggregate bundles allows for the elimination of the geotextile fabric and the reduction of the number of pipes required too provide a complete system. Again the synthetic aggregate bundles provide protection of the holes and slots of the multi-pipe system and the removal of the geotextile fabric prevents the clogging filter phenomenon. The arrangement could take on the appearance of one pipe or a fractional pipe attached to a synthetic aggregate bundle or multiple pipes attached to or surrounded by multiple synthetic aggregate bundles. Since multi-pipe is a combination of the four inch diameter corrugated pipe, we would not preclude the use of a single pipe or fractional pipe (½ Pipe) or the use of smaller or larger diameter pipes. Further, the use of solid (PVC type) pipe would be a possibility in this design. The drawings depict some of the possible iterations, but not all. The general concept of protecting the distribution device and eliminating potential hazards is the same.

Panel Drains

There are existing products in use today for drainage applications that still require the use of crushed stone or rock. One such product is referred to as a panel drain. The panel drain varies in width and height and is generally rectangular in presentation. Panel drains are placed along the edge of a foundation or retaining wall to prevent infiltration of ground water. Gravel is then packed around and behind the product for support and protection. The panel drain is an excellent candidate for use with the invention. The panel could be placed on top of, adjacent to, inside of, or under a synthetic aggregate bundle for use in drainage or septic applications. Panel drains are manufactured in large rolls. They could be transported to the site and fastened to the synthetic aggregate bundles, or the panels could be made inside the synthetic aggregate bundle as a pre-assembled unit. This invention incorporates non-conventional “pipe” usage and teaches away from the Houck Drainage System.

Comparison to Existing Products

The following compares the improvements achieved by the use of the invention with existing products.

1. GENERAL CONSIDERATIONS

In the on-site waste water field, there are a number of variables that are critical to the function, operation, and design of a subsurface dispersal system. Some of the variables are the storage volume, soil interface area, the flow characteristics, effluent liquid levels, maximum effluent height underneath the dispersal pipe, surface area, void volume for aggregate laden systems and hydraulic conductivity as it relates to Darcy's Law of flow through permeable media. As these variables are examined, measurable quantities are identified and compared. For the purpose of comparison, the properties are quantified per linear foot of trench, that is, for each linear foot of trench excavated or trench foot. There are other identifiable mensurations that describe the dispersal system characteristics. (e.g., gallons/foot, square feet/foot)

The age old standard and most commonly used dispersal system is the gravel trench. The gravel standard has been the impetus for alternative products such as chambers, the Houck drainage system, multi-pipe, and a number of others. In all such cases, the products are rated in comparison to the three foot wide by one foot deep gravel trench and an equivalent trench length is established.

In order to establish the variables for comparison, one must first identify and quantify the properties of the gravel standard trench 10 of FIG. 1. The first variable to establish is the soil interface area (SIA). The SIA is defined as the contact area between the dispersal system and the soil. In FIG. 1, the SIA is the width of the trench bottom 12, 36 inches added to the length of both 12 inch sides 14, 16 (36 in.+24 in.=5 Ft.). Considering a one foot length of trench, that yields a SIA of 5 square feet per linear foot of trench.

The void volume of the gravel standard trench is determined at two levels. The first is the maximum level or the fully ponded level. That is when the trench is filled to capacity. The second is the volume under the invert or bottom of the pipe. The maximum storage capacity of a gravel trench with a 4 inch pipe is 9.5 gallons per linear foot of trench. The volume of the gravel trench below the pipe invert or beneath the pipe is 4.5 gallons per linear foot of trench. This dramatic decrease in the storage volume reflects the current regulatory method for calculating the standard. This is the regulatory community's way of building in a factor of safety of almost 50%.

The conductivity of the gravel and its constituents (fines) determines the flow of the effluent through the gravel. The addition of fines in the gravel trench reduces the flow rate or presentment of the effluent to the soil as much as 75%. In practice, subsurface systems that do not use gravel and fines will receive a trench length reduction as compared to the gravel trench. If gravel requires a 100 foot long trench, it is common for alternative products to replace the gravel trench with 50% of the length required for a gravel system. As the use of a storage volume standard becomes more prevalent, the trench lengths for alternative systems will be adjusted to meet these criteria. The ability of the non-gravel trench to present the effluent to the trench more readily is reflected in the product's conductivity. The greater hydraulic conductivity values yield increased flow rates.

The final consideration is the effluent liquid height. Higher effluent levels in the trench generate higher hydraulic heads. Higher Hydraulic heads or increased pressure drives the effluent into the soil, thus generating higher flow rates or a more efficient and effective dispersal system. If the liquid level is artificially raised by filling an otherwise empty cavity with porous material, the same affect is achieved.

It should be noted that the addition of a synthetic aggregate bundle or bundles may on the surface appear to be obvious. Yet, in the 100-plus year history of on-site waste water systems the synthetic aggregate bundles described herein have not been tested or tried. In fact, just the opposite is true. Manufacturers of specific dispersal systems have discouraged the mixing or alteration of different products. Discouragement was due in part because of perceived warranty issues, but primarily because of monetary ones. The manufacturers did not want to share their respective customers with one another. In the end, the loser was and is the consumer. The invention provides a product that not only performs more efficiently and effectively, it provides a longer life system at potentially more competitive pricing.

Regulations govern the onsite market in the form of Department of Environmental Quality or Department of Health regulations that are generated from State and Federal statutes. The current climate in the regulatory community has a bent toward void volumes and trench width. With this in mind, a number of existing approved products may disappear. These products by themselves cannot meet the regulatory requirements as established. Their storage volumes and soil interface areas are wanting in the wake of the new regulations and without an innovation in their design the marketplace may be narrowed.

The best illustration of the demise of a subsurface system is the large diameter pipe system, shown in FIG. 2. This large diameter pipe 18 is often 6, 8, or 10 inches in diameter and is wrapped with a geotextile fabric or “sock” 20. “Sock Pipe” or LDP has enjoyed use under regulatory approvals that set a single 10 inch diameter pipe wrapped with a sock equivalent to a three foot wide gravel trench. LDP was the first of the alternative systems to get approval and has been around the longest. LDP has been proven to function at its intended sizing in the intended environment. With newer measurements methods in use, the regulatory community will not likely consider a three foot wide gravel trench that is one foot deep equal to a pipe that has outside dimensions of one foot, e.g., that on a volumetric scale, three cubic feet is equal to one cubic foot. Therefore, LDP may disappear as an approved product unless an innovation to the design is found.

Other alternative products may suffer the same fate or in some cases a slightly less severe penalty without innovation. Small plastic chambers and the Houck drainage system are two such products. Next to gravel, chambers and the HD systems are the prevalent dispersal systems in the marketplace. Plastic chambers of widths less than three feet are subject to demise under the current regulatory frenzy. Their void volumes are close to the standard gravel trench, however the widths and heights are lacking thereby reducing their soil interface area. HD systems are in a similar situation. Their soil interface areas are close, but the volume underneath the pipe is lacking. Translated, in order for alternative products to provide equivalent trenches as compared to gravel, the alternative product may have to provide substantially longer trench lengths. The consequent cost increase may lead to the demise of these products.

Longer trenches means higher installed cost in multiple areas. Longer drainfields require larger lot sizes, more material cost to fill the trenches, and increased labor cost to perform the excavation. Current drainfield economics provide a competitive equivalence for alternative products at reduced trench lengths. That is, as long as alternative drainfields are allowed to be installed at trench length reductions based on soil interface area or hydraulic conductivity, then they are competitive with gravel systems. Huge amounts of financial, political and physical resources have been expended to establish sizing criteria for subsurface drainfields. The efforts have not been with out bias. Each of the manufacturers has lobbied to promote their individual product benefits even if the regulations would eliminate others. Even if the demise of certain products is inevitable, the innovation provided by the invention revitalizes the opportunity for some subsurface dispersal systems.

2. EXISTING PRODUCTS

Houck Drainage Systems (EZflow™ Made by RING Industrial Group)

Referring to FIG. 3, the HDS employs a perforated and corrugated plastic pipe 26 with holes in it. The pipe 26 is concentrically surrounded with polystyrene aggregate 28 and encapsulated in netting to form a circular unit 30. Further, additional polystyrene 32 is encapsulated in netting without a pipe (e.g., 34, 34) and positioned adjacent, beside or underneath the pipe unit. The combination of these units comprises the HD system. The HD system uses tubular units with concentric placement of the drainage pipe. In some cases the pipe is offset to meet regulatory requirements that specify the distance from the invert of the pipe to the bottom of the trench. With only 6 inches of aggregate under the pipe the storage volume of the unit may be significantly reduced under new regulations.

The HDS product identified as EZ1203H is 36 inches wide and 12 inches deep. Currently, this product is installed at 50 liner feet per 100 linear feet of gravel. With these dimensions, it meets the Soil Interface Area (SIA) requirements. The total volume of the system is 13 gallons, but the volume under the invert of the pipe is 7.5 gallons. However, gravel has a system volume of 9.5 gallons per foot and 4.5 gallons per foot under the invert. Comparing the volumes under the pipe, EZ1203H may have to construct an additional 20% more trench than it is customarily used to providing. The cost of this alternative system has just increased by 20%.

By relocating or changing the geometry of the pipe, the invention provides the solution to the problem. In FIG. 4, moving the pipe(s) 26, 26 to the crevice between the adjacent bundles raises the invert to almost 10 inches. The storage volume is increased to 11 gallons per foot under the invert of the pipe. This 46% increase in void volume would insure that the product might continue to be installed at the maximum allowable trench length reduction of 50%. It might further allow the manufacture to decrease the diameter of the aggregate bundles 40 to further reduce the system cost. By reducing the diameter of the aggregate bundle, the volume and SIA number could be optimized for maximum economic benefit. Considering a similar comparison, it is generally perceived that a distribution pipe is round. Changing the geometry of the dispersal pipe might accomplish the same end result, e.g., changing the pipe geometry from round to rectangular would change the calculation point for volume underneath the pipe.

Referring to FIG. 5, a product for the foundation drainage market is identified as a drain board, panel drain or a J drain 42, 44. It is available in various internal geometries and dimensions, and is commonly used as an infiltration pipe to collect storm water. However, like any pipe its orientation can be varied to provide an exfiltration function or in the on-site industry a dispersal system. In accordance with the invention, and as shown in FIG. 6, placing the panel drain 42 horizontally on top of or inside of a single synthetic aggregate bundle 40 or multiple synthetic aggregate bundles 40, the drain board 42 becomes a distribution board. Similarly, the void volumes under the “pipe” invert would be 100% of the system capacity at whatever size the synthetic aggregate bundles needed to be to meet the regulatory requirements. In the previous example, where the EZ1203H system maximum volume was 13 gallons, this new system achieves the maximum volume without sacrificing SIA or volume below the invert.

The above, and the following illustrations and examples clearly define the uniqueness and the novel nature of the invention, i.e., it is more than an obvious combination of a variety of products. Rather, it is the result of applied engineering principles and the specific application of the same to solve a problem. Altering the conventional perception of a “round” pipe to be any conveyance device of any geometry that provides for implementation in infiltration or exfiltration applications broadens the scope and application of the invention.

Chamber Systems

Referring to FIG. 7, the plastic chamber 50 is manufactured in a number of sizes and configurations. The three basic sizes are 15 inches, 22 inches and 34 inches wide. Obviously, the larger width products weigh more and therefore contain more plastic material. The heavier weighted plastic parts cost more money than the lighter weight plastic chambers. The features of each of the products are specific to their dimension. The void volumes and soil interface areas increase with increased product dimensions. Again, following the previous logic and examples, the smaller width products may be eliminated from the approved products list because of their physical characteristics without some innovative system design changes.

The 15 inch chamber stores about 5 gallons of effluent and provides 2.5 square feet of SIA. Giving the current regulations, this product might meet the volume requirements for one to one length installations, but the SIA requirements indicate that twice the trench length would be required. Doubling the cost of this particular system by providing twice as much product and twice as much land for the installation may render this system obsolete. The invention provides the design innovation that will boost the SIA and storage volume physical properties to revitalize this product. Adding two of the synthetic aggregate bundles 40 (see FIG. 7) adjacent to the louvered sides of the small width chamber would increase the storage volume by 220% and the SIA by 225%. The product might be eligible for reduced trench lengths with the addition of synthetic aggregate bundles. Moreover, another synthetic aggregate bundle 40 could be placed inside of the chamber (see FIG. 8) to increase the hydraulic head of the system. Increasing the hydraulic head again increases the flow rate of the effluent into the soil.

In all such applications of the invention, the resulting location and geometry of the pipe improves the critical performance factors of a subsurface dispersal system. It is further noted that without the innovation provided by the invention, the products that it improves are destined for elimination. The invention offers design flexibility and improvements for all such subsurface dispersal systems.

3. Examples

Chambers

In the configuration shown in FIG. 7, synthetic aggregate bundles 40 are placed adjacent to the louvered sides of the chamber 50. The SIA is increased by 225%, void volume is increased by 220%, and hydraulic head is increased by 33% over the chamber without the synthetic aggregate bundles 40. In the configuration shown in FIG. 7, one or more synthetic aggregate bundles 40 provide improved louver or distribution device outlet protection.

In the configuration shown in FIG. 8, SIA is increased by 225%, void volume is increased by 220%, and hydraulic head is increased by 53% over the chamber without the synthetic aggregate bundles 40.

J Drain Board vs. EZflow 120P1P or 1203H

Drain board is currently not used as a drainfield product or exfiltration component. Utilizing panel drain boards would provide 100% of the SIA required as compared to either EZflow products of equivalent widths. Void Volume under distribution pipe is 100% of the available system capacity. The Hydraulic head would increase 100% compared to the EZflow products by virtue of pipe geometry and location EZflow 1203H

In the configuration shown in FIG. 4, the invention gives SIA of 5 SF/Ft, Void volume under pipe is increased 250% and hydraulic head is increased by 150%.

Large Diameter Pipe

FIG. 9 shows synthetic aggregate bundles 40 used to either side of large diameter pipe 60. Here, the addition of the synthetic aggregate bundles 40 increased SIA by 150%, while void volume increased by 200%. FIG. 10 shows synthetic aggregate bundles 40 used inside of the large diameter pipe 60, as well as to either side, which will also increase the hydraulic head.

Referring to FIG. 11, the light weight aggregate bundle 40 may be a cylindrical or elliptical 40c or triangular 40a, 40b, or rectangular 40d bundle of synthetic aggregate in the form of rubber crumb, shredded rubber, expanded polystyrene, styrenic blends or other such “light” weight aggregate that is contained in a netting or mesh. In accordance with the invention, one or more such light weight aggregate bundles may be placed adjacent to, around, or inside the existing drainage device to provide more surface area and strength, or to occupy void volume, to extend or modify trench dimensions in the x, y and z directions, and to optimize the variables of the Darcy equation for flow. FIGS. 12-19 provides further detail on other possible configurations, using the same drawing conventions and reference numerals as above. FIGS. 13-14 and 17 show the invention used with “half pipe” 66, which is not currently used in drainfield products.

Conclusion

Alternative media and devices for use as septic system drain fields or subsurface drainage are not new concepts. While “gravel” based systems are the norm, their utilization and presentation in the trench has evolved over a 100 year period. The understanding of the science and technology that describes the functionality of these systems has lagged behind current state of the art practices. As the understanding catches up to practice, regulations on the federal and state level are changing to meet this understanding. While variations of the rules exist from state to state, products employed for service in these industries must adapt and be modified to comply with these changing regulations in order to remain viable.

Products that do not comply with regulations are not purchased. If they are not purchased, then they cannot be placed in service. The invention enables compliance with regulations and can therefore be implemented as a drainage device.

The invention allows quick and immediate modification/adaptability of existing devices that are in service as a drainage medium to remain in use. The invention provides a contained light weight aggregate bundle comprised of the aggregate and contained within a geotechnical material (netting) that when added to an existing product becomes a new and improved system. The invention is useful with existing products like large diameter pipe, chambers, multi-pipes, and the single 4 inch pipe is combined with a synthetic aggregate bundle. In accordance with the invention, the light weight contained aggregate bundle is affixed or positioned adjacent to or inside or otherwise commingled with an existing product either in the field or as a complete unit provided by the manufacturer.

The invention is unique in that it allows existing drainage media or its components to form a new product that will meet the federal and state environmental regulations governing onsite waste water and subsurface drainage. The invention renders existing products commercially viable; without the invention, many of the existing products can no longer meet the regulatory requirements without the costs becoming prohibitive.

What has been shown and described is a drainage product which provides improved protection and strength for the distribution or conveyance medium. When used as a drainfield product, it improves distribution device outlet protection, and more uniform delivery of effluent throughout the trench, and promotes oxygenation of the effluent deposited in the distribution or conveyance medium. As a drainage product, it may be implemented for dewatering and storm water remediation. Such an infiltration medium acts similarly to the exfiltration devices described above, for the collection and transportation of storm water or for the purpose of dewatering.

While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific exemplary embodiment and method herein. The invention should therefore not be limited by the above described embodiment and method, but by all embodiments and methods within the scope and spirit of the invention as claimed.

Claims

1. A drainage product comprising:

at least one elongated conveyance component having at least one outlet, and at least one elongated aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned in relation to said at least one elongated conveyance component in at least one orientation selected from: placed adjacent to and abutting or beneath and abutting or on top of and abutting or inside of said at least one elongated conveyance component, or adjacent to said at least one outlet of said at least one elongated conveyance component, or between said at least one elongated conveyance component and a second elongated conveyance component, to provide a drainage product for sewage disposal, dewatering and storm water remediation systems; and

wherein said elongated conveyance component has a non-circular cross section.

2. (canceled)

3. A drainage product as in claim 1, wherein said elongated conveyance component comprises a chamber.

4. A drainage product as in claim 1, wherein said elongated conveyance component comprises a multi-pipe system.

5. (canceled)

6. (canceled)

7. (canceled)

8. A drainage product as in claim 1, wherein said elongated conveyance component comprises a solid type pipe.

9. A drainage product as in claim 1, wherein said elongated conveyance component comprises a drain board product.

10. A drainage product as in claim 1, wherein said elongated conveyance component comprise a half pipe product.

11. A drainage product as in claim 1, wherein a plurality of said elongated aggregate bundles are positioned in relation to said at least one elongated conveyance component in a plurality of orientations selected from: placed adjacent to and abutting or beneath and abutting or on top of and abutting or inside of said at least one outlet of said at least one elongated conveyance component, or between said at least one elongated conveyance component and said second elongated conveyance component, to provide a wastewater drainfield for a sewage disposal system with additional absorption area for a distribution medium.

12. A drainage product as in claim 1, wherein said light weight aggregate material is selected from a group comprising rubber crumb, shredded rubber, expanded polystyrene, and styrenic blends.

13. A drainage product as in claim 1, wherein said light weight aggregate material is contained in a netting or mesh.

14. A drainage product as in claim 1, wherein said at least one elongated aggregate bundle is positioned below and abutting said at least one elongated conveyance component.

15. A drainage product as in claim 1, wherein at least one elongated aggregate bundle is positioned to either side of and abutting said at least one elongated conveyance component.

16. A drainage product as in claim 15, wherein at least one elongated aggregate bundle is positioned inside of said at least one elongated conveyance component.

17. A drainage product as in claim 1, wherein said at least one elongated aggregate bundle is positioned above and abutting said at least one elongated conveyance component

18. (canceled)

19. A drainage product as in claim 1, wherein said at least one elongated aggregate bundle has a cross-sectional shape selected from circular, oval, rectangular and triangular.

20. A drainage product as in claim 1, wherein said elongated conveyance component is located at the lowest point and wherein said at least one elongated aggregate bundle is positioned in relation to said at least one elongated conveyance component in at least one orientation selected from: above, beside, or around said at least one elongated conveyance component.

21. (canceled)

22. A drainage product as in claim 9, wherein a plurality of said elongated aggregate bundles are positioned to take up the entire width of a trench below said drain board product, with said drain board product resting on two of said elongated aggregate bundles.

23. A drainage product as in claim 10, wherein said at least one elongated aggregate bundle is positioned below and supporting said half pipe product.

24. A drainage product as in claim 3, wherein at least one of said elongated aggregate bundles is positioned to either side of said chamber.

25. A drainage product as in claim 24, wherein at least one of said elongated aggregate bundles is positioned inside of said chamber.

26. A drainage product comprising:

at least three elongated aggregate bundles comprising a quantity of light weight aggregate material encapsulated in a geotechnical material;

said at least three elongated aggregate bundles positioned approximately parallel and abutting one another and in contact with a bottom surface of a trench;

at least two elongated conveyance components;

said at least two elongated conveyance components abutting at least two of said at least three elongated aggregate bundles approximately opposite said bottom surface; and

said at least two elongated conveyance components approximately parallel to said at least three elongated aggregate bundles.

27. A drainage product comprising:

at least one elongated drain board product;

at least one elongated aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned on a bottom surface of a trench;

said at least one elongated drain board product resting on top of said at least one elongated aggregate bundle.

28. A drainage product comprising:

at least one elongated conveyance component abutting and substantially parallel to a bottom surface of a trench;

at least one elongated aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned abutting and substantially parallel to one side of said at least one elongated conveyance component and said bottom surface; and

a second elongated aggregate bundle positioned abutting and substantially parallel to the other side of said at least one conveyance component and said bottom surface.

29. A drainage product as in claim 28, further including at least one elongated aggregate bundle positioned inside of said elongated conveyance component.

30. A drainage product as in claim 28, wherein said elongated conveyance component is a chamber.

31. A drainage product as in claim 28, wherein said elongated conveyance component is a pipe positioned within a third aggregate bundle approximately between the center of said third aggregate bundle and a side of said third aggregate bundle approximately diametrically opposite said bottom surface.

32. A drainage product comprising:

at least one elongated half pipe positioned on a bottom surface of a trench with the open half of said elongated half pipe positioned away from said bottom surface;

at least one elongated aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned on the open half of and approximately parallel to said elongated half pipe; and

at least one additional elongated aggregate bundle abutting and approximately parallel said at least one elongated aggregate bundle and positioned about opposite said elongated half pipe.

33. A drainage product comprising:

at least two elongated aggregate bundles comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned on a bottom surface of a trench;

said at least two elongated aggregate bundles substantially parallel to and abutting one another;

at least one elongated conveyance component positioned on top of, abutting, and substantially parallel to said at least two elongated aggregate bundles; and

at least two additional elongated aggregate bundles positioned on top of, abutting and substantially parallel to said at least one elongated conveyance component.

34. A drainage product comprising:

at least one elongated aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned on a bottom surface of a trench; and

at least one elongated conveyance component abutting said at least one elongated aggregate bundle approximately opposite said bottom surface and approximately parallel to said at least one elongated aggregate bundle.

35. A drainage product as in claim 34, wherein said at least one elongated conveyance component is a half pipe with open half abutting said at least one elongated aggregate bundle.

36. A drainage product as in claim 34, wherein said at least one elongated aggregate bundle consists of two elongated aggregate bundles substantially parallel to and abutting one another and one of said two elongated aggregate bundles is on top of the other of said two elongated aggregate bundles.

37. A drainage product comprising:

a plurality of elongated parallel and abutting conveyance components;

at least one of said plurality of elongated parallel and abutting conveyance components contacting a bottom surface of a trench;

at least one elongated aggregate bundle comprising a quantity of light weight aggregate material encapsulated in a geotechnical material positioned on said bottom surface; and

said at least one elongated aggregate bundle contacting and parallel to at least one of said plurality of elongated parallel and abutting conveyance components.

38. A drainage product as in claim 37, wherein at least one additional elongated aggregate bundle is positioned contacting and parallel to at least one of said plurality of elongated parallel and abutting conveyance components, contacting said bottom surface and opposite said at least one elongated aggregate bundle.