SURFACE WATER MITIGATION STRUCTURE

Abstract

A surface water mitigation structure suitable for use in the storage and treatment of contaminated surface water runoff. The runoff is processed through a multi-layered filtration and treatment system wherein the first layer is one or more permeable layers that is pervious enough to allow liquid runoff to pass through it and into a porous storage medium second layer that includes one or more remediating agents, and wherein the effluent from the surface water mitigation structure can be discharged to the ground, the surface, and/or a drainage system reduced or free of contaminants.

Claims

1-20. (canceled)

21. A surface water mitigation structure comprising: a) a cavity; said cavity is at least 3 inches deep; b) a permeable layer; said permeable layer is pervious and porous; said permeable layer is configured to allow water to pass through said permeable layer at a rate of at least 0.25 inches of water per square foot per hour; said permeable layer is formed of I) a permeable rigid composite; said permeable rigid composite including base material and binder; said base material includes one or more materials selected from the group consisting of limestone, shale, slate, sandstone, quartz, feldspar, dolomite, obsidian, mica, diorite, flint, granite, stone, metal, glass, rubber, ceramic, plastic, recycled concrete, recycled asphalt, expanded shale, expanded slate, recycled plastic, and recycled metal; said binder is used to at least partially bond together said base material; said permeable rigid composite having a composition and thickness to support a load on a top surface of said rigid permeable composite of at least 50 lbs./ft..sup.2 without breaking or cracking under such load; said base material constituting at least 55 wt. % of said permeable rigid composite; said binder constituting at least 5 wt. % of said permeable rigid composite; a total weight percent of said base material and said binder constitutes 90-100 wt. % of said permeable rigid composite; or II) a porous flexible layer and a support layer; said porous flexible layer positioned on or above a top surface of said support layer; said porous flexible layer configured to allow water to pass through said porous flexible layer at a rate of at least 0.25 inches of water per square foot per hour; said porous flexible layer having a thickness of at least 0.1 inches; a thickness of said porous flexible layer less than a thickness of said support layer; said porous flexible layer formed of a different material than said support layer; said porous flexible layer having a flexibility at least 30% greater than a flexibility of said support layer; said porous flexible layer partially or fully formed of A) a porous fiber mesh material, B) a porous flexible polymer sheet, or C) a porous flexible rubber sheet; and c) a porous storage medium layer positioned beneath said permeable layer; said porous storage medium layer comprising a first storage medium component that is a water-absorbent material; said first storage medium component includes one or more materials selected from the group consisting of limestone, shale, slate, expanded shale, and expanded slate; and wherein at least a portion of a top surface of said permeable layer is in fluid communication with said porous storage medium layer to allow water on a top surface of said permeable layer to flow into said porous storage medium layer.

22. The surface water mitigation structure as defined in claim 21, wherein said porous storage medium layer includes one or more remediating agents; said one or more remediating agents are 0.1-40 vol. % of said porous storage medium layer.

23. The surface water mitigation structure as defined in claim 21, wherein said porous storage medium layer is configured such that one cubic yard of porous storage medium layer can retain more than 10 gallons of water; said first storage medium component having an average particle size of 0.01-200 mm; a thickness ratio of said permeable layer to said porous storage medium layer is 1:1-20.

24. The surface water mitigation structure as defined in claim 22, wherein said porous storage medium layer is configured such that one cubic yard of porous storage medium layer can retain more than 10 gallons of water; said first storage medium component having an average particle size of 0.01-200 mm; a thickness ratio of said permeable layer to said porous storage medium layer is 1:1-20.

25. The surface water mitigation structure as defined in claim 21, further including a watertight barrier at least partially surrounding sides of said porous storage medium; said watertight barrier designed to prevent fluid flow into an exterior environment due to flow flowing through a side of said porous storage medium alongside which said watertight barrier is positioned.

26. The surface water mitigation structure as defined in claim 24, further including a watertight barrier at least partially surrounding sides of said porous storage medium; said watertight barrier designed to prevent fluid flow into an exterior environment due to flow flowing through a side of said porous storage medium alongside which said watertight barrier is positioned.

27. The surface water mitigation structure as defined in claim 21, wherein said permeable layer is said permeable rigid composite; said binder includes one or more materials selected from the group consisting of epoxy, urethane, polyurethane, acrylic, styrene, butadiene, and silicone.

28. The surface water mitigation structure as defined in claim 26, wherein said permeable layer is said permeable rigid composite; said binder includes one or more materials selected from the group consisting of epoxy, urethane, polyurethane, acrylic, styrene, butadiene, and silicone.

29. The surface water mitigation structure as defined in claim 27, wherein said permeable rigid composite has a composition and thickness to support a load on a top surface of said rigid and permeable composite capstone layer of least 300 lbs./ft..sup.2 without breaking under such load and has a deflection under such load of less than 5%; a thickness ratio of said permeable rigid composite to said porous storage medium is at least 1:1.2; said permeable rigid composite having a thickness of 0.1-5 inches.

30. The surface water mitigation structure as defined in claim 28, wherein said permeable rigid composite has a composition and thickness to support a load on a top surface of said rigid and permeable composite capstone layer of least 300 lbs./ft..sup.2 without breaking under such load and has a deflection under such load of less than 5%; a thickness ratio of said permeable rigid composite to said porous storage medium is at least 1:1.2; said permeable rigid composite having a thickness of 0.1-5 inches.

31. The surface water mitigation structure as defined in claim 27, wherein said permeable rigid composite includes 10-20 wt. % of a binder, and less than about 2 wt. % of an additive; said first particles include concrete and said second particle includes rubber; said water-absorbent material includes one or more materials selected from the group consisting of expanded shale and expanded slate.

32. The surface water mitigation structure as defined in claim 30, wherein said permeable rigid composite includes 10-20 wt. % of a binder, and less than about 2 wt. % of an additive; said first particles include concrete and said second particle includes rubber; said water-absorbent material includes one or more materials selected from the group consisting of expanded shale and expanded slate.

33. The surface water mitigation structure as defined in claim 31, wherein said permeable rigid composite includes said additive; said additive includes silane.

34. The surface water mitigation structure as defined in claim 32, wherein said permeable rigid composite includes said additive; said additive includes silane.

35. The surface water mitigation structure as defined in claim 21, wherein said permeable layer includes said porous flexible layer and said support layer; said porous flexible layer is configured to allow water to pass through said porous flexible layer at a rate of at least 0.25 inches of water per square foot per hour; said porous flexible layer has a thickness of at least 0.1 inches; said porous flexible layer is formed of a different material than said support layer; said porous flexible layer has a flexibility that is at least 30% greater than a flexibility of said support layer.

36. The surface water mitigation structure as defined in claim 26, wherein said permeable layer includes said porous flexible layer and said support layer; said porous flexible layer is configured to allow water to pass through said porous flexible layer at a rate of at least 0.25 inches of water per square foot per hour; said porous flexible layer has a thickness of at least 0.1 inches; said porous flexible layer is formed of a different material than said support layer; said porous flexible layer has a flexibility that is at least 30% greater than a flexibility of said support layer.

37. The surface water mitigation structure as defined in claim 35, wherein said support layer includes a plurality of pieces of support material connected together by an interlocking arrangement.

38. The surface water mitigation structure as defined in claim 36, wherein said support layer includes a plurality of pieces of support material connected together by an interlocking arrangement.

39. The surface water mitigation structure as defined in claim 37, wherein said support material includes a plurality of openings there through; an average size of said plurality of openings in said support layer is less than said average particle size of said porous storage medium layer.

40. The surface water mitigation structure as defined in claim 38, wherein said support material includes a plurality of openings there through; an average size of said plurality of openings in said support layer is less than said average particle size of said porous storage medium layer.

41. The surface water mitigation structure as defined in claim 21, wherein said surface water mitigation structure is configured to form a surface of one of a roadway, a parking lot, a sidewalk, a cart path, a bicycle path, a horse stall, a drainage basin, an animal shelter, an animal stall, a barn, a stable, or a kennel.

42. The surface water mitigation structure as defined in claim 34, wherein said surface water mitigation structure is configured to form a surface of one of a roadway, a parking lot, a sidewalk, a cart path, a bicycle path, a horse stall, a drainage basin, an animal shelter, an animal stall, a barn, a stable, or a kennel.

43. The surface water mitigation structure as defined in claim 40, wherein said surface water mitigation structure is configured to form a surface of one of a roadway, a parking lot, a sidewalk, a cart path, a bicycle path, a horse stall, a drainage basin, an animal shelter, an animal stall, a barn, a stable, or a kennel.

44. A method for using a surface water mitigation structure to at least partially remove contaminants; said method comprises: a) providing a surface water mitigation structure; said surface water mitigation structure comprising: i) a cavity; said cavity is at least 3 inches deep; ii) a permeable layer; said permeable layer is pervious and porous; said permeable layer is configured to allow water to pass through said permeable layer at a rate of at least 0.25 inches of water per square foot per hour; said permeable layer is formed of I) a permeable rigid composite; said permeable rigid composite including base material and binder; said base material includes one or more materials selected from the group consisting of limestone, shale, slate, sandstone, quartz, feldspar, dolomite, obsidian, mica, diorite, flint, granite, stone, metal, glass, rubber, ceramic, plastic, recycled concrete, recycled asphalt, expanded shale, expanded slate, recycled plastic, and recycled metal; said binder is used to at least partially bond together said base material; said permeable rigid composite having a composition and thickness to support a load on a top surface of said rigid permeable composite of at least 50 lbs./ft..sup.2 without breaking or cracking under such load; said base material constituting at least 55 wt. % of said permeable rigid composite; said binder constituting at least 5 wt. % of said permeable rigid composite; a total weight percent of said base material and said binder constitutes 90-100 wt. % of said permeable rigid composite; or II) a porous flexible layer and a support layer; said porous flexible layer positioned on or above a top surface of said support layer; said porous flexible layer configured to allow water to pass through said porous flexible layer at a rate of at least 0.25 inches of water per square foot per hour; said porous flexible layer having a thickness of at least 0.1 inches; a thickness of said porous flexible layer less than a thickness of said support layer; said porous flexible layer formed of a different material than said support layer; said porous flexible layer having a flexibility at least 30% greater than a flexibility of said support layer; said porous flexible layer partially or fully formed of A) a porous fiber mesh material, B) a porous flexible polymer sheet, or C) a porous flexible rubber sheet; and iii) a porous storage medium layer positioned beneath said permeable layer; said porous storage medium layer comprising a first storage medium component that is a water-absorbent material; said first storage medium component includes one or more materials selected from the group consisting of limestone, shale, slate, expanded shale, and expanded slate; and wherein at least a portion of a top surface of said permeable layer is in fluid communication with said porous storage medium layer to allow water on a top surface of said permeable layer to flow into said porous storage medium layer. and wherein at least a portion of said surface mitigation structure is positioned in said cavity; and b) at least partially removing contaminates ion a fluid as said fluid at least partially flows through said surface mitigation structure.

45. The method as defined in claim 45, wherein said surface water mitigation structure is configured to form a surface of one of a roadway, a parking lot, a sidewalk, a cart path, a bicycle path, a horse stall, a drainage basin, an animal shelter, an animal stall, a barn, a stable, or a kennel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Reference may now be made to the drawings, which illustrate various non-limiting embodiments that the invention may take in physical form and in certain parts and arrangement of parts wherein:

[0071] FIG. 1 is a cross-sectional perspective illustration of one surface water mitigation structure according to one non-limiting aspect of the present invention;

[0072] FIG. 2 is a perspective illustration of a section of the permeable composite capstone layer of FIG. 1;

[0073] FIG. 3 is a perspective illustration of one non-limiting base material that can be used to at least partially form the permeable composite capstone layer of FIG. 1;

[0074] FIG. 4 is a perspective illustration of a comparison of rain fall on a prior art paved surface and the surface water mitigation structure of FIG. 1;

[0075] FIG. 5 is an illustration of a sidewalk or path formed by the surface water mitigation structure of the present invention and also illustrates an optional curb structure along the outer perimeter of the top surface of the surface water mitigation structure.

[0076] FIG. 6 is a cross-sectional perspective illustration of another surface water mitigation structure according to one non-limiting aspect of the present invention;

[0077] FIG. 7A is a cross-section view of a flexible layer that can be used in the surface water mitigation structure of FIG. 6;

[0078] FIG. 7B is a cross-section view of another flexible layer that can be used in the surface water mitigation structure of FIG. 6;

[0079] FIG. 7C is a top plan view of the flexible layer of FIG. 7B;

[0080] FIG. 8 is a top plan view of a non-limiting permeable support layer that can be used in the surface water mitigation structure of FIG. 6;

[0081] FIG. 9 is a method for forming a surface water mitigation structure; and,

[0082] FIG. 10 is another method for forming a surface water mitigation structure.

DETAILED DESCRIPTION OF THE NON-LIMITING EMBODIMENTS

[0083] A more complete understanding of the articles/devices, processes and components disclosed herein can be obtained by reference to the accompanying drawings. These figures are merely schematic representations based on convenience and the ease of demonstrating the present disclosure, and are, therefore, not intended to indicate relative size and dimensions of the devices or components thereof and/or to define or limit the scope of the exemplary embodiments.

[0084] Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the particular structure of the embodiments selected for illustration in the drawings and are not intended to define or limit the scope of the disclosure. In the drawings and the following description below, it is to be understood that like numeric designations refer to components of like function.

[0085] The singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0086] As used in the specification and in the claims, the term “comprising” may include the embodiments “consisting of” and “consisting essentially of.” The terms “comprise(s),” “include(s),” “having,” “has,” “can,” “contain(s),” and variants thereof, as used herein, are intended to be open-ended transitional phrases, terms, or words that require the presence of the named ingredients/steps and permit the presence of other ingredients/steps. However, such description should be construed as also describing compositions or processes as “consisting of” and “consisting essentially of” the enumerated ingredients/steps, which allows the presence of only the named ingredients/steps, along with any unavoidable impurities that might result therefrom, and excludes other ingredients/steps.

[0087] Numerical values in the specification and claims of this application should be understood to include numerical values which are the same when reduced to the same number of significant figures and numerical values which differ from the stated value by less than the experimental error of conventional measurement technique of the type described in the present application to determine the value.

[0088] All ranges disclosed herein are inclusive of the recited endpoint and independently combinable (for example, the range of “from 2 grams to 10 grams” is inclusive of the endpoints, 2 grams and 10 grams, and all the intermediate values).

[0089] The terms “about” and “approximately” can be used to include any numerical value that can vary without changing the basic function of that value. When used with a range, “about” and “approximately” also disclose the range defined by the absolute values of the two endpoints, e.g. “about 2 to about 4” also discloses the range “from 2 to 4.” Generally, the terms “about” and “approximately” may refer to plus or minus 10% of the indicated number.

[0090] Percentages of elements should be assumed to be percent by weight of the stated element, unless expressly stated otherwise.

[0091] Referring now to the drawings, wherein the showings are for the purpose of illustrating at least one non-limiting embodiment of the invention only and not for the purpose of limiting the invention, FIGS. 1-10 illustrate non-limiting surface water mitigation structures in accordance with the present invention.

[0092] In the drawings, like reference numerals refer to like elements throughout, and the various features are not necessarily drawn to scale. The singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. As used in the specification and in the claims, the term “comprising” may include the embodiments “consisting of” and “consisting essentially of.” The terms “comprise(s),” “include(s),” “having,” “has,” “can,” “contain(s),” and variants thereof, as used herein, are intended to be open-ended transitional phrases, terms, or words that require the presence of the named ingredients/steps and permit the presence of other ingredients/steps. However, such description should be construed as also describing compositions or processes as “consisting of” and “consisting essentially of” the enumerated ingredients/steps, which allows the presence of only the named ingredients/steps, along with any unavoidable impurities that might result therefrom, and excludes other ingredients/steps.

[0093] The present invention is directed to a surface water mitigation structure that can be used as a water treatment and/or filtration system which is durable enough to be used in outdoor applications (e.g., roadways, parking lots, sidewalks, cart paths, bicycle paths, urban tree surrounds, horse stalls, drainage basins, animal shelters, animal stalls, barns, stables, kennels, etc.), and which surface water mitigation structure and/or topping has a multi-layered structure that includes remediating agents used to at least partially treat contaminants that flow through the surface water mitigation structure.

[0094] As illustrated in FIG. 1, the surface water mitigation structure 10 includes at least two layers, namely a) a permeable composite capstone layer 20 and b) a porous storage medium layer 30. The permeable composite capstone layer 20 is positioned above the porous storage medium layer 30, and the porous storage medium layer 30 is positioned in, on, or above a ground surface G. As illustrated in FIG. 1, a cavity has been formed in a portion of the ground surface and the porous storage medium layer 30 has been placed in the cavity and on top of the undisturbed ground to partially or fully fill the cavity. The permeable composite capstone layer 20 is configured to support substantial loads while also being pervious enough to allow top water runoff to pass through the permeable composite capstone layer. The porous storage medium that forms the porous storage medium layer 30 is configured to absorb and/or hold water that has passed through the permeable composite capstone layer 20. The porous storage medium layer is designed to at least contain and/or be inoculated with one or more remediating agents that are designed to break down contaminants in the runoff that has passed through the permeable composite capstone layer. The porous storage medium layer is also typically designed to retain and/or absorb the runoff for a period of time (e.g., 2 minutes to 10 days and all values and ranges therebetween) to allow the remediating agents to break down the contaminants before the runoff enters the surrounding environment. In one non-limiting embodiment, the average residence time of the runoff in the porous storage medium layer is at least about 5 minutes, and typically at least about 10 minutes.

[0095] Referring now to FIGS. 1-4, the permeable composite capstone layer 20 can be formed from a base material 22 formed of particles of natural materials (e.g., limestone, shale, slate, sandstone, quartz, feldspar, dolomite, obsidian, mica, diorite, flint, granite, stone, metal, etc.) and/or one or more man-made materials (e.g., glass, rubber, ceramic, plastic, recycled concrete, recycled asphalt, expanded shale, expanded slate, recycled plastic, recycled metal, etc.) which are bonded together with one or more binders (e.g., epoxy resin, urethane or polyurethane resin, acrylic resin, styrene butadiene resin, silicone resin, vinylester resin, phenolic resin, polyester resin or fiberglass resin, etc.). FIG. 3 illustrates granules of base material 22 that can be used to form the permeable composite capstone layer 20. FIG. 2 illustrates a sample of a permeable composite capstone layer 20 wherein the base materials are bonded together by a binder to form a porous, durable and rigid structure. In one specific, non-limiting example, the permeable composite capstone layer includes recycled concrete, granite and/or stone and recycled rubber bonded together with urethane binder (e.g., urethane or polyurethane resin). The average particle size of the base material is 0.5-100 mm (and all values and ranges therebetween) based on ISO 14688-1:2002, and typically about 1-60 mm based on ISO 14688-1:2002, and more typically 3-30 mm based on ISO 14688-1:2002 based on ISO 14688-1:2002. The base material generally constitutes 55-99.5 wt. % (and all values and ranges therebetween) of the permeable composite capstone layer, and the binder generally constitutes 0.5-45 wt. % (and all values and ranges therebetween) of the permeable composite capstone layer. The permeable composite capstone layer can also include one or more additives.

[0096] The permeable composite capstone layer is generally poured and then spread on the top surface of the porous storage medium layer 30 prior to the binder fully curing or setting. Once the binder has set and/or cured, a rigid permeable composite capstone layer is formed. Generally, the top surface of the permeable composite capstone layer is formed to be generally flat prior to the binder fully setting and/or curing. In such an operation, the bottom surface of the permeable composite capstone layer is generally non-flat and rough; however, this is not required. It can be appreciated that for smaller areas (e.g., less than 10 ft..sup.2), preformed sections of permeable composite capstone layer can be formed and fully cured and then later inserted on top of the porous storage medium layer. However, for surface areas larger than 10 ft..sup.2, the permeable composite capstone layer is typically poured and spread on the top surface of the porous storage medium layer prior to the binder fully setting and/or curing.

[0097] FIG. 9 illustrates a non-limiting method for forming a surface water mitigation structure 10. A mixture of non-fully cured or set binder and base material is provided. The mixture can be formed prior to, during, or after the formation of the porous storage medium layer. The ground surface is prepared for the porous storage medium layer. The type of ground preparation is non-limiting. One type of ground preparation is digging a hole, trench, cavity, etc. in the ground. Another type of ground preparation is grading and/or clearing the ground surface. As can be appreciated, other types of ground preparation can be used. After the ground preparation, the porous surface medium components are poured onto or otherwise inserted in or laid on the prepared ground surface. Prior to, during, and/or after the porous surface medium components being placed on the prepared ground surface, microbes can be applied to the porous surface medium components. The porous surface medium components can be pretreated with microbes, and/or microbes can be added to the porous surface medium components by pouring a liquid microbe solution onto the porous surface medium components. As can be appreciated, other or additional methods can be used to apply microbes to the porous surface medium components. After the porous surface medium components are applied to the prepared ground surface and optionally spread out on the ground surface, the mixture of binder and base material is applied on top of the porous surface medium components. For small areas (e.g., no more than 10′×10′), a capstone layer can optionally be pre-formed and then be placed over the porous surface medium components. However, generally, a pre-set or pre-cured mixture of binder and base material is poured over the porous surface medium components and then spread over the porous surface medium components to obtain a desired thickness and top surface profile. Typically, the pre-set or pre-cured mixture of binder and base material is applied directly to the top surface of the porous surface medium components; however, this is not required. After the pre-set or pre-cured mixture of binder and base material is applied over the porous surface medium components, the mixture of binder and base material is allowed to substantially or fully set or cure, thereby forming the rigid, permeable composite capstone layer. After the binder and base material are substantially or fully set or cured, the porous surface medium components can be treated with microbes. Such treatment is generally accomplished by pouring a liquid microbe solution onto the top surface of the rigid, permeable composite capstone layer and allowing the solution to flow through the rigid, permeable composite capstone layer and then charge the porous surface medium components with the microbes. As can be appreciated, other or additional methods can be used to apply microbes to the porous surface medium components the porous surface medium components.

[0098] Generally, the permeable composite capstone layer is relatively thin compared to its surface area. In one non-limiting embodiment, the ratio of depth of the permeable composite capstone layer to the surface area of the permeable composite capstone layer is at least 1:50, and has an average thickness of at least 0.5 inch, typically about 0.5-8 inches (and all values and ranges therebetween), and more typically about 1-6 inches, and still more typically 1-4 inches. As illustrated in FIGS. 1 and 4, the thickness of the permeable composite capstone layer 20 is less than the thickness of the porous storage medium layer 30. The thickness ratio of the permeable composite capstone layer to the porous storage medium layer is generally 1:1.2 to 1:500 (and all values and ranges therebetween), and typically 1:3 to 1:15.

[0099] The permeable composite capstone layer is typically configured to be abrasion resistant, freeze/thaw resistant, and/or strong enough to support major loads (e.g., the weight of a person, car, truck, train, bus, etc.). In one non-limiting embodiment, the permeable composite capstone layer has a composition and thickness wherein a one-inch thick slab of cured permeable composite capstone layer having a length of two feet and a width of one foot can support a load on a top surface of the permeable composite capstone layer of at least 50 lbs./ft..sup.2 without breaking under such load, typically the permeable composite capstone layer has a composition and thickness wherein a one-inch thick slab of cured permeable composite capstone layer having a length of two feet and a width of one foot can support a load on a top surface of the permeable composite capstone layer of at least 100 lbs./ft..sup.2 without breaking under such load, more typically the permeable composite capstone layer has a composition and thickness wherein a one-inch thick slab of cured permeable composite capstone layer having a length of two feet and a width of one foot can support a load on a top surface of the permeable composite capstone layer of at least 200 lbs./ft..sup.2 without breaking under such load, and still more typically the permeable composite capstone layer has a composition and thickness wherein a one-inch thick slab of cured permeable composite capstone layer having a length of two feet and a width of one foot can support a load on a top surface of the permeable composite capstone layer of at least 500 lbs./ft..sup.2 without breaking under such load. In another non-limiting embodiment, the cured permeable composite capstone layer is a rigid layer that does not break or deflect more than 10% under a load on the top surface of the permeable composite capstone layer of at least 50 lbs./ft..sup.2 wherein the capstone layer is a slab having a thickness of one inch and having a length of two feet and a width of one foot, typically the permeable composite capstone layer is a rigid layer that does not break or deflect more than 5% under a load on the top surface of the permeable composite capstone layer of at least 50 lbs./ft..sup.2 wherein the capstone layer is a slab having a thickness of one inch and having a length of two feet and a width of one foot, and more typically the permeable composite capstone layer is a rigid layer that does not break or deflect more than 2% under a load on the top surface of the permeable composite capstone layer of at least 50 lbs./ft..sup.2 wherein the capstone layer is a slab having a thickness of one inch and having a length of two feet and a width of one foot.

[0100] The weight ratio of binder to base material in the permeable composite capstone layer is typically about 1:2 to about 1:16. In one specific embodiment, the weight ratio of binder to base material is 1:4 to 1:10. The permeable composite capstone layer is configured to allow water to pass through the permeable composite capstone layer at a rate of at least 1 inch of water per square foot per hour, and typically at least 2 inches of water per square foot per hour.

[0101] The porous storage medium layer 30 is configured to retain sufficient amounts of fluid to support remediating agent activity, yet durable enough to support loads of the permeable composite capstone layer. The porous storage medium layer can be made from one or more materials and associated void spaces. In non-limiting embodiments, the porous storage medium layer can include one or more storage medium components selected from the group consisting of shale, slate, expanded shale, and/or expanded slate. The average size of one or more storage medium components used to at least partially form the porous storage medium layer is about 0.10 mm to about 100 mm (and all values and ranges therebetween). The amount of storage medium components included in the porous storage medium layer is generally selected based on the amount of water to be stored or retained for a period of time in the porous storage medium layer.

[0102] Water and other liquids that enter the porous storage medium layer after passing through the permeable composite capstone layer are temporarily retained within the porous storage medium layer. The porous storage medium layer generally is designed to retain water and other liquids for at least about 0.1 day.

[0103] In one non-limiting arrangement, the thickness of the permeable composite capstone layer 20 is about 0.1-10 inches, typically 0.5-6 inches, and can with loads without cracking of 50-200,000 lbs./ft..sup.2 (and all values and ranges therebetween), typically 1000-100,000 lbs./ft..sup.2, more typically 5000-50,000 lbs./ft..sup.2, and still more typically 7500-20,000 lbs./ft..sup.2. In another or alternative non-limiting arrangement, the thickness of the porous storage medium layer 30 is about 0.2-100 ft., typically 0.3-50 ft., and more typically about 0.3-20 ft. The composition of the porous storage medium layer 30 is generally selected such that each ton (i.e., 2000 lbs.) of the porous storage medium layer can store about 10-200 gal. of water, typically 25-100 gal. of water, and more typically about 40-75 gal. of water.

[0104] The permeable composite capstone layer and/or the porous storage medium layer can optionally include a watertight and/or impermeable material 40 (e.g., plastic sheet or board, waterproof fabric, vinyl sheet, etc.) on one or more sides of the permeable composite capstone layer and/or the porous storage medium layer. The watertight and/or impermeable material can reduce or prevent water and other liquids from flowing out one or more of the sides of the permeable composite capstone layer and/or porous storage medium layer and only allow the water and other liquids to flow through the permeable composite capstone layer and into the top of the porous storage medium layer and out the bottom of the porous storage medium layer and out any controlled side openings in the porous storage medium layer; however, this is not required. The porous storage medium layer can serve the purpose of a support layer and/or a collection basin. The porous storage medium layer can optionally support the growth of remediating agents in the form of microbes. The porous storage medium layer can optionally include water and/or nutrients for the purpose of supporting and/or encouraging the growth and activity of the one or more microbes in the porous storage medium layer.

[0105] The porous storage medium layer can include one or more expanded lightweight storage medium components. One or more remediating agents are generally added to the porous storage medium layer. In one non-limiting configuration, the porous storage medium layer includes about 10 to about 99.9 wt. % of a first storage medium component, about 0 to about 89.9 wt. % of a second storage medium component, about 0.1 to about 30 wt. % of a first remediating agent, about 0 to about 30 wt. % of a second remediating agent, and less than about 10 wt. % of an additive. The dry porous storage medium layer is composed of approximately 65-98 vol. % storage medium components. The average particle size of the storage medium component is at least 0.2 mm in diameter; however, this is not required. The microbes in the porous storage medium layer constitute about 2-18 vol. % of the dry porous storage medium layer. The porous storage medium layer provides a flow rate of the runoff in the porous storage medium layer of about 0.001-1 feet per second per square foot of surface area (and all values and ranges therebetween). In one non-limiting embodiment, the expanded lightweight storage medium layer is formed from at least 50% wt. % expanded shale and/or expanded slate, and typically at least 75 wt. expanded shale and/or expanded slate.

[0106] Referring now to FIG. 4, there is a side-by-side comparison of how surface water is treated when contacting the top surface of a prior art paved surface (as shown on the right side of FIG. 4) and when contacting the top surface of the surface water mitigation structure 10 of the present invention (as illustrated on the left side of FIG. 4). When a liquid contacts the top surface of the prior art paved surface, the liquid stays on the top surface of the prior art paved surface until it is washed away, such as by rain. The runoff from the prior art paved surface either drains into a drain or runs off into the surrounding environment. If the drain is not connected to a sewer system, the runoff enters into the surrounding environment. Runoff that includes contaminants that flow into the surrounding environment can potentially damage the surrounding environment. In contrast, when such a liquid contacts the top surface of the permeable composite capstone layer 20 of the surface water mitigation structure 10, the liquid may partially or fully pass through the permeable composite capstone layer. If the liquid only partially passes through the permeable composite capstone layer (as when a significant amount of surface water such as from a rain storm falls on the permeable composite capstone layer), such surface water will eventually cause some or all of the liquid to pass through the permeable composite capstone layer. Once the liquid passes through the permeable composite capstone layer, the liquid contacts and is temporarily retained and/or absorbed in the one or more materials and/or voids in the porous storage medium layer. One or more contaminants in the liquid can be partially or fully broken down or eliminated by one or more remediating agents that are located in the porous storage medium layer. As such, when water exits the porous storage medium layer and into ground G, the amount of contaminates in the water are typically reduced. As such, the surface water mitigation structure of the present invention is capable of removing contaminants and/or pollutants from water (e.g., storm water runoff, waste water runoff, etc.) by subjecting the water to a multi-layered filtration and treatment system. After the water has been treated by the surface water mitigation structure, the treated water can be discharged to the ground, the surface, and/or a drainage system.

[0107] Referring now to FIG. 5, there is illustrated a path P that is formed of a surface water mitigation structure 10 in accordance with the present invention and an optional curb or border parameter C that is positioned between the top surface of the surface water mitigation structure 10 and the surface of ground G. The curb or border parameter can be used to partially or fully retain surface water on the top surface of the surface water mitigation structure until the surface water passes through permeable composite capstone layer 20 of the surface water mitigation structure 10.

[0108] During construction of the surface water mitigation structure, the porous storage medium layer is inserted onto the top of the ground surface. It is not uncommon that a portion of a ground surface is removed prior to the porous storage medium layer being inserted onto the top of the ground surface; however, this is not required. The one or more remediating agents in the porous storage medium layer can be included in the porous storage medium layer at the time that the porous storage medium layer is inserted on the ground surface and/or at some later time. After the porous storage medium layer has been applied to the ground surface, the permeable composite capstone layer is applied to the top of the porous storage medium layer. Generally, the permeable composite capstone layer is formed on the porous storage medium layer by applying a mixture of base material and uncured/unset or partially-cured/set binder to the top surface of the porous storage medium layer. After the binder in the permeable composite capstone layer has sufficiently cured and/or set, the surface water mitigation structure can be used. The one or more remediating agents for use in the porous storage medium layer can be initially inserted into the porous storage medium layer and/or the porous storage medium layer can be recharged with one or more remediating agents by pouring a solution of the one or more remediating agents onto the top surface of the permeable composite capstone layer; however, this is not required.

[0109] FIGS. 6-8 and 10 illustrate another non-limiting embodiment of the surface water mitigation structure 100 of the present invention. The surface water mitigation structure 100 includes a flexible porous layer 110, a support layer 120, and a porous storage medium layer 30. The porous storage medium layer 30 can be the same as the porous storage medium layer described above with respect to FIGS. 1-4. As illustrated in FIG. 6, the porous storage medium layer 30 is positioned on top of undisturbed ground G. The surface water mitigation structure 100 can also optionally include a watertight and/or impermeable material 40 (e.g., plastic sheet or board, waterproof fabric, vinyl sheet, etc.) on one or more sides of the flexible porous layer 110, the support layer 120 and/or the porous storage medium layer 30. Hence, watertight and/or impermeable material 40 (when used) has the same or similar function as the watertight and/or impermeable material described above with respect to FIGS. 1-4. The surface water mitigation structure 100 can also optionally include an elevated watertight and/or impermeable material or barrier on the top edge regions of the flexible porous layer 110 and/or the support layer 120 to inhibit or prevent runoff of water from the top edges of the flexible porous layer 110 and/or the support layer 120.

[0110] The first or top layer of the surface water mitigation structure 100 is a flexible porous layer 110 that is positioned on top of the support layer 120, which support layer 120 is positioned between the top flexible porous layer 110 and the porous storage medium layer 30. Generally, the top flexible porous layer is a preformed layer that is available in pre-cut sheets of material, or is available in rolls of material that can be cut to length and/or width.

[0111] In one non-limiting embodiment, the top flexible layer is partially or fully formed of a fiber mesh 112 that can a woven or non-woven mesh. The fiber can be a natural or man-made fiber. The thickness of the fiber mesh is generally at least 0.1 inches and is typically 0.1-5 inches. One non-limiting type of top flexible layer is a non-woven polypropylene fiber sheet such as Geotex® 401 by Popex. Such top flexible layers are generally available in precut sheets or in rolls of 50 ft. or more and a width of 5-15 feet at a thickness of 0.1-2 inches; however, the material can be available in other dimensions. The top flexible layer 110 generally has a liquid permeability of at least 0.25 inch of water per square foot per hour.

[0112] As illustrated in FIG. 7A, the fibers in the top portion of the fiber mesh 112 or all of the fibers of the fiber mesh 112 can optionally include and/or be coated with a polymer coating 114. The thickness of the coating is non-limiting. If the polymer coating is applied such that a polymer layer is formed on the top surface of the fiber mesh as illustrated in FIG. 7A, then the polymer coating is formulated to be a porous coating. However, if the individual fibers of the fiber mesh are coated with the polymer, then the polymer may or may not be a porous polymer. Generally, the thickness of the polymer coating (when used) is at least 0.01 micron.

[0113] In another non-limiting embodiment, the top flexible porous layer 110 is a flexible polymer or rubber sheet 116 that may or may not have a reinforcement scrim or mat 118 as illustrated in FIG. 7B. One non-limiting type of polymer sheet is a vinyl polymer sheet. One non-limiting type of rubber sheet is a pervious rubber sheet that is formed of particles of rubber that are adhesively connected together (e.g., polyurethane binder, etc.). The thickness of the polymer or rubber sheet is generally at least 1 mm and typically 1 mm to 2 inch. If the polymer or rubber sheet is non-porous or has limited porosity, one or more openings 119 can be formed through the polymer or rubber sheet to obtain the desired amount of liquid flow through the sheet as illustrated in FIG. 7C. When one or more openings are included in the polymer or rubber sheet, the diameter of the one or more openings is generally less than 5 mm, and typically less than 3 mm. The polymer or rubber sheet is generally a preformed sheet. Such top flexible layers are generally available in precut sheets or in rolls of 50 ft. or more and a width of 5-15 feet at a thickness of 0.1-2 inches; however, the material can be available in other dimensions. The top flexible layer generally has a liquid permeability of at least 0.25 inch of water per square foot per hour.

[0114] The support layer 120 is configured to provide support to the top flexible porous layer 110. The support layer is generally formed of a different material from the top flexible support layer. The support layer generally is less flexible than the top flexible layer. Generally, the support layer is at least 30% less flexible than the top flexible layer. Generally, the thickness of the support layer is greater than the thickness of the top flexible layer; however, this is not required. The support layer can be formed of a variety of materials such as plastic or rubber material. In one non-limiting embodiment, the support layer is formed of a non-porous material (e.g., plastic material, some other polymer material or rubber material) and includes a plurality of openings or holes 122 that are formed fully through the non-porous material to enable liquid to flow through the support layer. When one or more openings are included in the support layer, the diameter of the one or more opening is generally at least 0.1 mm. The number and size of the openings in the support layer are selected that the flowrate of water through 1 ft..sup.2 of the support layer is at least 0.1 inch of water per square foot per hour. The support layer is generally a preformed layer. The thickness of the support layer is generally at least 0.25 inches.

[0115] The pieces of support layer can optionally be configured to be interlocking as illustrated in FIG. 9 so that a plurality of pieces of support layer can be connected together. In such a configuration, the pieces of support layer can includes structures such as a tongue or connection leg 124 and groove or connection cavity 126 that enable the pieces of support layer to be connected together. As can be appreciated, other means can be used to connect together the pieces of the support layer (e.g., hook and loop fastener, tape, adhesive, staples, melted seam connection, etc.).

EXAMPLE 1

[0116] A walking or bike path is formed of the surface water mitigation structure of the present invention that includes a porous storage medium layer and a capstone layer. The ground surface is prepared by digging the ground surface to form a trench or cavity in the ground surface that is about 3-24 inches deep, and typically about 4-12 inches deep. Thereafter, a porous storage medium layer that includes limestone, expanded shale and/or expanded slate is inserted into the trench or cavity in the ground surface. Typically, the porous storage medium layer is inserted into the trench or cavity in the ground surface by pouring the particles of the porous storage medium layer into the trench or cavity in the ground surface. The average size of the particles of the storage medium components is about 0.2 mm to about 500 mm, and typically about 5-150 mm, and more typically about 10-80 mm. Generally, the average thickness of the porous storage medium layer is 3-24 inches, and typically 4-12 inches. The limestone, expanded shale and/or expanded slate constitutes about 50-100 wt. % of the porous storage medium layer, and typically about 80-100% of the porous storage medium layer. After the porous storage medium layer is inserted into the trench or cavity in the ground surface, a pre-set or pre-cured mixture of urethane resin and/or polyurethane resin and a base material (e.g., rubber, granite, concrete, stone, quartz, etc.) is added to the top surface of the porous storage medium layer. The urethane or polyurethane resin constitutes about 12-25 wt. % of the mixture and the base material constitutes about 75-88 wt. % of the mixture. One specific, non-limiting example, the permeable composite capstone layer includes a base material having an average particle size of 3-18 mm that is formed of first and second types of particles, wherein the first type of particle includes one or more of limestone, shale, slate, sandstone, quartz, feldspar, dolomite, obsidian, mica, diorite, flint, granite, stone, metal, glass, ceramic, recycled concrete, expanded shale, expanded slate, recycled metal, and/or recycled glass (e.g., granite, stone, quartz, concrete, etc.), and the second type of particle includes one or more of rubber, plastic, recycled asphalt, recycled plastic, and/or recycled rubber (e.g., recycled rubber, etc.), and wherein weight ratio of the first type of particle to the second type of particle is 1:10 to 0.1:1 (and all values and ranges therebetween), and wherein the first and second types of particles constitute 85-100 wt. % of the base material, and wherein the base material is bonded together with a binder that is formed of 80-100% one or more of epoxy resin, urethane and/or polyurethane resin, acrylic resin, styrene butadiene resin, silicone resin, vinylester resin, phenolic resin, polyester resin and/or fiberglass resin (e.g., polyurethane resin, etc.), and wherein the total weight of the base material and the binder constitutes about 90-100 wt. % of the permeable composite capstone layer. The pre-set or pre-cured mixture of urethane or polyurethane resin and base material is spread over the top surface of the porous storage medium layer such that the pre-set or pre-cured mixture of urethane or polyurethane resin and base material has a generally flat top surface and an average thickness of about 0.5-8 inches, and typically about 1-4 inches. The pre-set or pre-cured mixture of urethane or polyurethane resin and base material is then allowed to substantially or fully set or cure to form the rigid, permeable capstone layer. The bottom surface of the capstone layer bonds to a portion of the top surface of the porous storage medium layer during the setting or curing of the binder. The capstone layer is able to support a load on a top surface of the permeable composite capstone layer of at least 300 lbs./ft..sup.2 without breaking under such load, and has a deflection under such loads of less than 5%. After the mixture of urethane or polyurethane resin and base material is substantially or fully set or cured, a solution of microbes can be optionally poured onto the top surface of the capstone layer to charge the porous storage medium layer with the microbes. As can be appreciated, a solution of microbes can be optionally poured onto the top surface of the porous storage medium layer prior to forming the capstone layer on the porous storage medium layer to charge the porous storage medium layer with the microbes. The porous storage medium layer can optionally be periodically recharged with microbes as required by pouring a solution of microbes onto the top surface of the capstone layer. The capstone layer is formulated and configured to enable surface water on the top surface of the capstone layer to pass through the capstone layer at a rate of at least 5 inches of water per square foot per hour. The capstone layer forms a rigid top surface for the surface water mitigation structure to enable humans, pets and animals to safely walk on the top surface of the capstone layer, and to also allow bikes, children's wagons, and strollers to safely move on the top surface of the capstone layer without the cracking and breaking of the capstone layer.

EXAMPLE 2

[0117] A vehicle road or vehicle parking lot is formed of the surface water mitigation structure of the present invention that includes a porous storage medium layer and a capstone layer. The ground surface is prepared by digging the ground surface to form a trench or cavity in the ground surface that is about 12-48 inches deep. Thereafter, a porous storage medium layer that includes limestone, expanded shale and/or expanded slate is inserted into the trench or cavity in the ground surface. Typically, the porous storage medium layer is inserted into the trench or cavity in the ground surface by pouring the particles of the porous storage medium layer into the trench or cavity in the ground surface. The average size of the particles of the storage medium components is about 0.2 mm to about 500 mm, and typically about 5 mm to 150 mm, and more typically about 10 mm to 80 mm. Generally, the average thickness of the porous storage medium layer is 12-48 inches, and typically 12-36 inches. The limestone, expanded shale and/or expanded slate constitutes about 50-100 wt. % of the porous storage medium layer, and typically about 80-100% of the porous storage medium layer. After the porous storage medium layer is inserted into the trench or cavity in the ground surface, a pre-set or pre-cured mixture of urethane or polyurethane resin and base material (e.g., rubber, granite, concrete, quartz, etc.) is added to the top surface of the porous storage medium layer. The urethane resin and/or polyurethane resin constitutes about 12-25 wt. % of the mixture and the base material constitutes about 75-88 wt. % of the mixture. One specific, non-limiting example, the permeable composite capstone layer includes a base material having an average particle size of 3-18 mm that is formed of first and second types of particles, wherein the first type of particle includes one or more of limestone, shale, slate, sandstone, quartz, feldspar, dolomite, obsidian, mica, diorite, flint, granite, stone, metal, glass, ceramic, recycled concrete, expanded shale, expanded slate, recycled metal, and/or recycled glass (e.g., granite, stone, quartz, concrete, etc.), and the second type of particle includes one or more of rubber, plastic, recycled asphalt, recycled plastic, and/or recycled rubber (e.g., recycled rubber, etc.), and wherein weight ratio of the first type of particle to the second type of particle is 1:10 to 0.1:1 (and all values and ranges therebetween), and wherein the first and second types of particles constitute 85-100 wt. % of the base material, and wherein the base material is bonded together with a binder that is formed of 80-100% one or more of epoxy resin, urethane resin and/or polyurethane resin, acrylic resin, styrene butadiene resin, silicone resin, vinylester resin, phenolic resin, polyester resin and/or fiberglass resin (e.g., polyurethane resin, etc.), and wherein the total weight of the base material and the binder constitutes about 90-100 wt. % of the permeable composite capstone layer. The pre-set or pre-cured mixture of urethane or polyurethane resin and base material is spread over the top surface of the porous storage medium layer such that the pre-set or pre-cured mixture of urethane or polyurethane resin and base material has a generally flat top surface and an average thickness of about 1-12 inches, and typically about 2-6 inches. The pre-set or pre-cured mixture of urethane or polyurethane resin and base material is then allowed to substantially or fully set or cure to form the rigid, permeable capstone layer. The bottom surface of the capstone layer bonds to a portion of the top surface of the porous storage medium layer during the setting or curing of the binder. The capstone layer is able to support a load on a top surface of the permeable composite capstone layer of at least 1000 lbs./ft..sup.2 without breaking under such load, and has a deflection under such loads of less than 5%. After the mixture of urethane or polyurethane resin and base material is substantially or fully set or cured, a solution of microbes can be optionally poured onto the top surface of the capstone layer to charge the porous storage medium layer with the microbes. As can be appreciated, a solution of microbes can be optionally poured onto the top surface of the porous storage medium layer prior to forming the capstone layer on the porous storage medium layer to charge the porous storage medium layer with the microbes. The porous storage medium layer can optionally be periodically recharged with microbes as required by pouring a solution of microbes onto the top surface of the capstone layer. The capstone layer is formulated and configured to enable surface water on the top surface of the capstone layer to pass through the capstone layer at a rate of at least 5 inches of water per square foot per hour. The capstone layer forms a rigid top surface for the surface water mitigation structure to enable humans, pets and animals to safely walk on the top surface of the capstone layer, also allow bikes, children's wagons, and strollers to safely move on the top surface of the capstone layer, and also allow cars, trucks and other vehicles to safely move on the top surface of the capstone layer without the cracking and breaking of the capstone layer.

EXAMPLE 3

[0118] A horse stall or animal shelter with flexible layer is formed of the surface water mitigation structure of the present invention that includes a porous storage medium layer, a support layer and a flexible porous layer. The ground surface is prepared by digging the ground surface to form a trench or cavity in the ground surface that is about 3-24 inches deep, and typically about 4-10 inches. Thereafter, a porous storage medium layer that includes limestone, expanded shale and/or expanded slate is inserted into the trench or cavity in the ground surface. Typically, the porous storage medium layer is inserted into the trench or cavity in the ground surface by pouring the particles of the porous storage medium layer into the trench or cavity in the ground surface. The average size of the particles of the storage medium components is about 0.2 mm to about 500 mm, and typically about 5-150 mm, and more typically about 10-80 mm. Generally, the average thickness of the porous storage medium layer is 3-24 inches, and typically 4-10 inches. The limestone, expanded shale and/or expanded slate constitutes about 50-100 wt. % of the porous storage medium layer, and typically about 80-100% of the porous storage medium layer. After the porous storage medium layer is inserted into the trench or cavity in the ground surface, a support layer is place over the top surface of the porous storage medium layer. The support layer is formed of a rubber material having an average thickness of about 0.3-2 inches, and typically about 0.5-1.5 inches. The rubber support layer generally has a durometer hardness of 40-80 Shore A, and typically about 55-65 Shore A. A plurality of perforations or holes are formed in the rubber material of the support layer so that liquid can pass through the support layer. The average size of the openings is generally 0.05-4 inches in diameter, and typically 0.1-3 inches in diameter, and more typically about 0.5-2.5 inches in diameter. The support layer is generally applied as pieces of material on the top surface of the porous storage medium layer. The pieces of support layer can optionally be connected together; however, this is not required. Generally, the support layer is formed of preformed pieces of material. After the support layer has been inserted over the porous storage medium layer, a flexible porous layer is inserted over the top surface of the support layer. The flexible porous layer is formed of a non-woven polymer material (e.g., polypropylene, etc.) having an average thickness of 0.2-1.5 inches, and typically 0.3-0.5 inches. Generally, the flexible porous layer is provided in a roll of material that is cut to length. If the width of the roll of material of flexible porous layer is too small, sheets of flexible porous layer can be placed side by side. The side-by-side sheets of flexible porous layer can optionally be connected together by various means (e.g., hook and loop fastener, tape, adhesive, staples, sewn connection, melted seam connection, etc.). Prior to and/or after the flexible porous layer is applied over the top surface of the support layer, a solution of microbes can be optionally poured onto the top surface of the flexible porous layer or top surface of the support layer to charge the porous storage medium layer with the microbes. As can be appreciated, a solution of microbes can be optionally poured onto the top surface of the porous storage medium layer to charge the porous storage medium layer with the microbes prior to placing the support later on top of the porous storage medium layer. As can be appreciated, the porous storage medium layer can optionally be periodically recharged with microbes as required by pouring a solution of microbes on the flexible porous layer, support layer and/or the porous storage medium layer. The flexible porous layer and support layer form a top surface for the surface water mitigation structure to enable humans, pets and animals to safely walk on the top surface of the flexible porous layer. The top surface provides a strong, yet soft, surface for animals to walk on can be easily cleaned by simply spraying water on the top surface of the flexible porous layer. The flexible porous layer can be easily replaced when worn after excessive use. In some non-limiting applications, a drain system can be placed under the surface water mitigation structure to remove water after it has passed through the surface water mitigation structure.

[0119] To aid the USPTO and any readers of this application and any resulting patent in interpreting the claims appended hereto, Applicant does not intend any of the appended claims or claim elements to invoke 35 U.S.C. 112(f) unless the words “means for” or “step for” are explicitly used in the particular claim.

[0120] It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in the constructions set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. The invention has been described with reference to preferred and alternate embodiments. Modifications and alterations will become apparent to those skilled in the art upon reading and understanding the detailed discussion of the invention provided herein. This invention is intended to include all such modifications and alterations insofar as they come within the scope of the present invention. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention, which, as a matter of language, might be said to fall therebetween.