Abstract:
The invention is a filter device, apparatus and system used to filter contaminants from liquids, such as water, particularly surface water runoff. The invention is configured to capture sediment, debris, and soluble and insoluble contaminants, including gas, oils and metals that enter the device. The invention consists of an adapter ring, an outer casing, a first filter material, an interior mesh, a blabla filter, and an inner casing. The invention is configured for easy installation within existing manhole frames without significantly impacting the height of the manhole cover and may be used within manholes for underground dry wells, storm drains, catch basins and other similar types of water collection structures.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/588,688 filed on Jan. 20, 2012 which is expressly incorporated herein in its entirety by reference thereto. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally screens and filtration devices, specifically screen and filtration devices for use in manholes and water collection basins in and around parking lots, streets and other paved areas. More specifically, the invention relates to a filter device that can be used to capture sediment and debris which otherwise would enter and accumulate within the structures. The invention removes soluble and insoluble contaminants from fluids passing through the device (typically rain water but sometimes including the improper dumping of motor oil or gas) and into the water collection basin, particularly gasoline, motor oil, metals, and polycyclic aromatic hydrocarbons (PAHs) and other gasoline combustion byproducts, which are known to accumulate in surface runoff and otherwise enter into and contaminate drywells, surrounding soils, ground water and surrounding water bodies, and the environment. The present invention also relates to a device that can be used to decease the required maintenance on such water collection structures and increase their life expectancy and performance. 
       BACKGROUND OF THE INVENTION 
       [0003]    Water collection structures, such as, for example, underground dry wells, storm drains, or catch basins are designed for water storage and dispersion, and surge protection. They assist with the handling, removal, and disposal of water, most commonly surface water and storm water runoff. They also act as sediment and debris collection basins. 
         [0004]    The large majority of these water collection structures are passive structures, meaning water flows into them and through them under the influence of gravity. Some underground water collection structures have a solid surface mounted cover with underground inputs, e.g., pipes. The cover helps prevent solids and liquids from entering the structure through the top. When access is desired, the cover is removed, typically using a crowbar or the like. 
         [0005]    More commonly for water collection structures, particularly around, for example, parking lots and streets, the cover is perforated to allow water to flow into the structure through the cover. The perforations in the surface mounted covers are typically sized to help prevent accident and injury, to limit the size of debris entering the drywell, and to provide openings for the flow of surface water runoff into the structure. Although the perforated covers screen out some larger insoluble contaminants and debris that would otherwise enter the water collection structure, they are incapable of screening debris that is smaller than the perforations, including many fine insoluble contaminants and soluble contaminants. Water flow into the structure may also derive from inlet pipes directed into the structure from other sources, which may also include other dry wells, storm drains, catch basins and/or overflows. Debris, dirt, garbage and other contaminants that enter water collection structures typically settle to the bottom and accumulate over time. 
         [0006]    Water entering the structure typically dissipates into the surrounding soils, sometimes first through a surrounding gravel and/or geo-fabric under the influence of gravity and may also combine, eventually, with surrounding groundwater or other water bodies. Water collection structures may discharge collected water through their structural rings which typically include slots hole or other openings in the sidewalls and/or through the bottom of the structure which may also likewise be perforated. Some structures are interconnected by pipes for increased capacity or for overflow protection. 
         [0007]    Modern water collection structures, e.g., dry wells, typically have a large interior storage volume constructed of reinforced concrete cylinders or rings which are stacked upon each other, depending on the depth of the well, with perforated sides and sometimes bottoms. For example, the dry well for a parking lot storm drain is usually buried below the parking lot and is covered with a surface mounted metal grate which allows fluids (e.g. water) to pass enter into dry well while keeping out larger debris. The number and size of drywells that exist on a property is typically determined by the size of the property, the typical rainfall for the region, expected water flows, and the surrounding environmental conditions (e.g., soil conditions and topography). 
         [0008]    Dry wells, storm drains, and other similar types of catch basins, particularly those located on or near gas stations and/or in or around parking lots, are particularly susceptible to receiving contaminated surface runoff. Storm water may become contaminated while running down the road or other impervious surfaces, such as parking lot asphalt, a gas station&#39;s pavement, or from lawn chemical runoff. Surface water runoff tends to pick up gasoline, motor oil, heavy metals, trash, sand, dirt, leaves and other pollutants, debris, and sediments, as well as fertilizers and pesticides. Roads, parking lots, and gas stations are major sources of nickel, copper, zinc, cadmium, lead and polycyclic aromatic hydrocarbons (PAHs), combustion byproducts of gasoline, and other fossil fuels. Roof runoff also contributes high levels of synthetic organic compounds and zinc (from galvanized gutters). These contaminants often make their way into water collection structures accumulate in the sediment within the structure, and most likely enter surrounding soils and groundwater. The resulting contamination poses great health risks to individuals, wildlife and the environment. 
         [0009]    Eventually, over time, without proper cleaning and maintenance (which is common for these structures due in part to the difficulty with seeing what is happening inside of them) the debris and sediment entering these water collection structures accumulates and clogs the drainage openings. One result is undesirable water accumulation in the structure and water flooding at the inlet surface. Another result is accumulation of contamination in the structure. 
         [0010]    Structures containing contaminated solid debris must undergo remediation to remove and properly dispose of the contaminated sediment and debris and perhaps, depending upon the extent of the contamination, treatment/remediate surrounding soils and waters. The cost of remediation is typically high and often interferes with the daily operation and use of the property. 
         [0011]    There is a need for a device, apparatus and system to help with the maintenance of these water collection structures, that also reduces the aforementioned environmental impacts by filtering out contamination at the inlet of the water collection structures, that increases the useful life of the water collection structures by decreasing the rate of sediment and debris accumulation inside them, and that helps avoid costly remediation and maintenance expenses. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention is a filter device, apparatus, and system used to screen debris and to filter contaminants from liquids, such as water, particularly surface water runoff, in and around parking lots, streets and other paved areas, particularly gas stations. While the invention will be described in connection with certain embodiments, it will be understood that the invention is not limited to those embodiments. To the contrary, the invention includes all alternatives, modifications and equivalents as may be included within the spirit and scope of the present invention. 
         [0013]    Water collection structures, including underground dry wells, storm drains, or catch basins typically have a surface manhole as their point of entry located at ground level. The manhole is typically comprised of a circular manhole frame with the top of the frame about flush with the surrounding ground, e.g., the pavement or concrete surface. Manhole frame comes in various shapes and sizes (e.g., round, rectangular, etc.) depending upon the type of installation (e.g., base supported or cast). The manhole cover is correspondingly configured to removably fit within the manhole frame with an upper surface about equal in height to the top of the manhole frame when installed. 
         [0014]    The present invention is a filter device, apparatus and system intended to be installed within existing manhole frames without substantially affecting the height of the manhole cover. The invention is easily installed and maintained. The invention screens debris and filters out most (if not all depending on the filters utilized) soluble and insoluble contaminants from the fluids passing through the invention and into the water collection structure without substantially impeding the flow rate into the water collection structure. 
         [0015]    A preferred embodiment of the invention is a filter device comprising of an adapter ring, an outer casing, an interior mesh, an inner casing, and at least two filters, a first filter used for removing finer solids and contaminants (soluble and insoluble) and a second filter for removing larger, non-soluble, materials. 
         [0016]    The adapter ring is configured about circular in shape comprising an upper lip and a lower lip fixedly connected to each other by a connecting member. The adapter ring has a top end and a bottom end. The upper lip is configured in an outwardly direction such that it will securely rest in and on the manhole frame on which it will be installed. Accordingly, for round manhole frames with round covers, the upper lip of the adapter ring is configured round with an outside diameter slightly less than the inner diameter of the opening in the manhole frame for the cover. The lower lip is configured in an inwardly direction such that is can hold up and support the outer casing and the rest of the device&#39;s components when installed in the adapter ring. The aperture through the adapter ring is equal in size to the inside diameter of the lower lip. The aperture is configured so that it is greater in diameter than the outside diameter of the outer casing so that the outer casing can slide/pass through the aperture up to its collar. 
         [0017]    The outer casing is configured in the shape of a waste basket, comprising a base, an about cylindrically shaped perimeter wall, and a collar at the top of the perimeter wall. The outer casing has an inside and an outside. The collar on the outer casing is configured in an outwardly direction such that it will securely rest on the top side of the lower lip of the adapter ring on which it will be installed. 
         [0018]    The first filter is preferably a fibrous lipophilic geo-textile material capable of filtering fine solids and contaminants, such as, for example, oil, petroleum, and hydrocarbons, while still allowing water to pass through. Preferably, the first filter is a rectangular piece of filter fabric material capable of covering all or most of the interior of the perimeter wall of the outer casing. Most preferably, a the lowest portion of the outer casing&#39;s perimeter wall is left uncovered by the first filter to provide an underflow for the device which helps prevent clogging and water backup. The first filter is positioned between the inside of the outer casing and an interior mesh. 
         [0019]    The interior mesh is mesh wire or plastic, or the like, having perforations. Preferably it it a sheet of material formable into the shape of a cylinder tube such that the height of the interior mesh tube is about equal to the height of the outer casing&#39;s perimeter wall and the diameter of the interior mesh tube is slightly smaller than the diameter of the outer casing perimeter wall with the difference between the two diameters being about equal to the thickness of the first filter fabric. 
         [0020]    The inner casing is an about cylindrically shaped sleeve comprising a perimeter wall and a collar at one end. In the preferred embodiment, the inner casing perimeter wall is solid without perforations and without a base. The inner casing has aperture through its length. The outside diameter of the inner casing is slightly smaller than the diameter of the interior mesh, with the difference between the two diameters being about equal to the thickness of the first filter fabric. The collar on the inner casing is configured in an outwardly direction such that it will securely rest in and on the collar of the outer casing on which it will be installed. The height of the inner casing&#39;s perimeter wall is less than the height of the outer casing&#39;s perimeter wall. 
         [0021]    The second filter is a semi-rigid material coarser than the first filer capable of filtering larger solids and debris, such as, for example, leaves and branches, sand, and garbage including bottles, cans, cigarette butts, paper, plastic and any other larger solids that may bypass through the openings found in the manhole cover. The second filter is positioned between the interior mesh and the outside of an inner casing. Preferably, the height of the second filter is not the entire height of the outer casing perimeter wall. Most preferably, the height of the second filter up from the base of the outer casing is about ⅓ to ½ the height. Another piece of the second filter may also be positioned inside the device on top of the outer casing base covering the entire base. 
         [0022]    When the filter device is assembled, the first filter is positioned along the interior of the outer casing perimeter wall so as to leave a small gap between the first filter fabric and the outer casing base. The interior mesh is placed inside the outer casing and positioned along the internal surface of the first filter so as to firmly secure the first filter in place against the outer casing. A piece of the second filter is positioned on the base of the outer casing and another piece of second filter is positioned around the lower portion of the interior mesh inside the device. The inner casing is then positioned within the device until the collar on the inner casing rests upon the collar on the outer casing. With the adapter ring is positioned within the manhole, the device is placed through the adapter ring with the outer casing&#39;s collar resting upon the lower lip of the adapter ring. The manhole cover may be installed back on the manhole frame and on top of the inner casing collar. 
         [0023]    Debris and water passing through the manhole cover enters the interior of the device, including running along the interior surface of the inner casing&#39;s perimeter wall to the second filter. Large sediment and debris is retained by the second filter, the fine solids and water pass through. That which passes through the second filter travels up behind the inner casing perimeter wall through more of the second filter, through the interior mesh, through the first filter fabric where contaminants are removed, and then through the outer casing and out of the device. As water accumulates inside the filter device greater hydraulic forces are created to force the water through the filter and the device. A gap left between the first filter and the outer casing base functions as an underflow to help the device from overflowing during high flow event. 
         [0024]    With time, and depending on the particular application and environmental conditions, the device fills with sediment, debris and contaminants. Once the filter device is filled, has a restricted flow rate, and/or the first filter is saturated with contaminants, the interior mesh, the casings and filters are removed from the adapter ring, the filters are replaced and/or cleaned and the interior mesh, the casings and the new filters are re-installed within the adapter ring. 
         [0025]    The filter device of the present invention is configured for easy installation and removal in existing structures. The device may be installed within existing frames for underground dry wells, storm drains, catch basins and other similar types of water collection structures without modifying shapes or configurations for existing manhole frames or covers. The device captures sediment and debris which otherwise would enter and accumulate within the structure. The device also drastically reduces contamination in and around the structures by capturing soluble and insoluble contaminants/pollutants in the device&#39;s filter(s). Also, by reducing the amount of sediment and debris that would otherwise enter and accumulate within these structures, the present invention helps increase the overall life expectancy and performance of the water collection structures in which it has been installed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the general description of the invention given above and the detailed description of an embodiment given below, serve to explain the principles of the present invention. Similar components of the devices are similarly numbered for simplicity. 
           [0027]      FIG. 1  is a perspective view of an individual placing the device according to the invention into an existing manhole frame. 
           [0028]      FIG. 2  is a perspective and cutaway view of the device installed in an existing manhole frame with the manhole cover installed on the device. 
           [0029]      FIG. 3  is a perspective view of the device shown in two parts, the adapter ring and the remainder of the device fully assembled as shown during installation into the manhole frame. 
           [0030]      FIG. 4  is an enlarged view of a portion of the device shown in  FIG. 3 . 
           [0031]      FIG. 5  is a cross section view of the adapter ring shown in  FIG. 3 . 
           [0032]      FIG. 6  is cross section elevation taken at  5 - 5  of  FIG. 3  showing the components of the device, except for the adapter ring, in the assembled position. 
           [0033]      FIG. 7  is an exploded view of the device shown in  FIG. 5  also including the adapter ring. 
           [0034]      FIG. 8  is an cross section view of the device shown installed depicting the flow path through the device. 
           [0035]      FIG. 9  is a perspective view of a rectangular adapter ring with two circular apertures for two filter devices. 
           [0036]      FIGS. 10 and 11  are perspective views of another embodiment of the invention with a flat pan base configuration on the outer casing and on a basket shaped inner casing. 
           [0037]      FIG. 12  is another embodiment of the invention which combines/integrates the adapter ring into the outer casing. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0038]    The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the filter device, apparatus and system and, together with the general description of the invention given above and the detailed description of an embodiment given below, serve to explain the principles of the present invention. Similar components of the devices are similarly numbered for simplicity. 
         [0039]    One embodiment of the invention is shown in  FIGS. 1-8 . Filter device  101  consists of an adapter ring  110 , an outer casing  120 , interior mesh  145 , inner casing  130 , and at least two filters, a second filter  150  to remove larger, non-soluble materials before the water reaches a first filter  140  used to remove contaminants (soluble and insoluble). 
         [0040]    Adapter ring  110  consists of an upper lip  111  and a lower lip  112  fixedly connected to each other by a connecting member  113 . Adapter ring  110  is about circular in shape. Upper lip  111  and lower lip  112  are about perpendicularly positioned with respect to connecting member  113  and about parallel with respect to each other. The adapter ring  110  has a top end and a bottom end. The upper lip  111  is configured in an outwardly direction from the middle of the adapter ring  110  such that it can securely rest in and on a manhole frame  105  on which it will be installed. Accordingly, for round manhole frame  105  with a round cover  107 , the upper lip  111  of adapter ring  110  is configured round with an outside diameter slightly less than the inner diameter of the opening in the manhole frame  105  for the manhole cover  107 . The lower lip  112  is configured in an inwardly direction toward the middle of the adapter ring  110  such that is can hold up and support the outer casing  120  when installed in the adapter ring  110 . Aperture  114  through the adapter ring  110  is formed by the inside diameter of the edge of the lower lip  112  which is configured large enough for the outer casing  120  to pass through the aperture  114  up to a collar  121  on the outer casing  120 . 
         [0041]    Preferably, the adapter ring  110  is a sturdy material strong enough to support the rest of the device  101  when installed onto the adapter ring  110 . Adapter ring  110  may be made of steel or any other of a variety of materials, including but not limited to other metals, such as brass, galvanized steel, aluminum and iron, or other materials such as plastic, synthetic polymers or any material which is rigid and preferably resistant to corrosion. The material used can also be painted for corrosion resistance and to reduce the likelihood of foreign substances sticking to surfaces. The thickness/gauge of the particular material used for fabrication can also be varied. 
         [0042]    The height Z, of connecting member  113  is the difference in height between upper lip  110  and lower lip  112 . This height Z can vary. The height Z allows for the other components of the device (e.g., the outer casing  120 , interior mesh  145 , inner casing  130 , and the filters  140  and  150 ) to be installed such that the top of the device is not higher than the top surface on the upper lip  111  of the adapter ring  110 . The height Z of connecting member  113  may also be varied so as to vary the depth of the device below the manhole cover  107 . 
         [0043]    For the embodiment shown in  FIGS. 1-8 , upper lip  111  is about circular in shape but it is understood that other configurations are within the scope of the invention depending on the intended application and depending on the size and shape of the opening in the manhole frame or in the water collection structure. For example, in another embodiment, the upper lip  111  may be rectangular with a circular lower lip  112  and internal aperture  114 . The configuration of the lower lip  112  can be varied so long as the shape of the collar on the outer casing  120  can be supported by the lower lip  112 . 
         [0044]    The overall size of adapter ring  110  can also be varied so as to accommodate different sizes of dry wells, storm drains, manholes or anywhere else the device will be installed. Adapter ring  110  could also include a plurality of apertures  114  to support a plurality of filter devices as shown in  FIG. 9 . Adapter ring  110  can additionally be fitted with gasket(s) or other seal(s) (not shown) between the manhole frame  105  and the underside of the upper lip  111  and/or the top of the lower lip  112  and the underside of the collar  121  on the outer casing  120 . The seal prevents fluids, e.g., surface water runoff, from bypassing device and entering the water collection structure without filtration. 
         [0045]    Other embodiments of the invention could further include alignment and/or locking means to hold the components in a desired alignment or position with respect to each other. For example, it may be desired to maintain the adapter ring  110  in a particular alignment/position on the manhole frame  105  and/or to hold the outer casing  120  in a particular position on the adapter ring  110 . Such means include adhesives, slots and protrusions, fasteners such as screws, bolts and clamps, and locks, or, if adapter ring  110  and manhole frame  105  are made of metal, by welding adapter ring  110  to the manhole frame  105 . 
         [0046]    The outer casing  120  is configured in the shape of a waste basket, comprising a base  125 , an about cylindrically shaped perimeter wall  122 , and a collar  121  at the top of the perimeter wall  122 . The outer casing  120  has an inside and an outside. The collar  121  on the outer casing  120  is configured in an outwardly direction from its middle such that it will rest on the lower lip  112  of the adapter ring  110  on which it will be installed. 
         [0047]    Preferably, outer casing  120  is about cylindrical in form although other shapes and sizes can also be used depending on the particular application and the shape of the manhole opening and the water collection structure in which device  1  is installed. The height X of outer casing perimeter wall  122  can also be varied to make it deeper or shallower according to the intended application and as a means of varying the open and/or closed surface area of filter device and its maximum design flow rates. Outer casing perimeter wall  122  can also be formed in a cone configuration, tapering (either inward or outward), or other geometric shapes. 
         [0048]    The top of the outer casing  120  includes an about circular collar  121 . The collar  121  is configured in an outwardly direction from the middle of the outer casing  120  such that it can securely rest on the lower lip  112  of the adapter ring  110 . Accordingly, the outside diameter of collar  121  is greater than the diameter of the aperture  114  in the adapter ring  110 . Collar  121  is configured such that it fits within adapter ring  110 , below upper lip  111 . Collar  121  may be configured with protrusions (not shown) that interlock into holes or apertures in lower lip  112  and/or connecting member  113  of adapter ring  110 . Alternatively, the protrusions may be located on lower lip  112  of adapter ring  110  with corresponding apertures in collar  121 . Outer casing  120  may otherwise be free to rotate/spin within adapter ring  110  when outer casing  120  is installed within aperture  114  of adapter ring  110 . 
         [0049]    Collar  121  can also be fitted with a gasket or other seal along its lower surface to form a seal with the upper surface of lower lip  112  when outer casing  120  is positioned within adapter ring  110 . 
         [0050]    Outer casing collar  121  can also include notches, grooves, holes for bolts/fasteners or any other means of securely, but removably fastening outer casing  120  to adapter ring  110  when the device is fully assembled (not shown). Outer casing  120  can also include notches, grooves, or a locking mechanism which would allow for the secure, but removable fastening of outer casing  120  to inner casing  130  when device is fully assembled. 
         [0051]    Outer casing perimeter wall  122  is permeable to allow liquids to flow through it. Preferably, outer casing perimeter wall  122  is formed like a steel wire mesh. The number, size and shape of the openings in the perimeter wall  122  can vary according to the particular application, the overall size of the device, the desired filter area, and/or the flow rate needed. Height X and/or the diameter of outer perimeter wall  122  may be increased or decreased to change its open surface area thereby altering flow rate through it. 
         [0052]    Outer casing base  125  is about circular and flat. Outer casing base  125  encloses the bottom of outer casing  120  along the bottom of perimeter wall  122 . Preferably, the diameter of outer casing base  125  is about equal to the diameter of aperture formed by the inner edge of the collar  121  which is about the same as the diameter of the perimeter wall  122 . In the embodiment shown, outer casing base  125  is solid with no perforations. Alternatively, outer casing base  125  may include a drain hole, preferably at the center of outer casing base  125 , but other positions are possible, or it may include a plurality of drain holes or be formed using a wire mesh material similar to that used to construct the outer casing&#39;s perimeter wall  122 . 
         [0053]    Furthermore, outer casing base  125  is not limited to a pie-pan style configuration having about perpendicular side walls along its outer perimeter that extend away from the base surface. In other embodiments, outer casing base  125  may be configured in a flat/solid configuration. In yet other embodiments, outer casing base  125  may include an external cone-shaped bottom extending away from the base or an internal cone-shaped configuration extending inward into the device. Such configurations have the added benefit of increasing the overall surface area through which flow and/or filtration can occur. The cone-shaped portion can be constructed of a mesh or porous material, the same material used for outer casing perimeter wall  122  and could be lined with a filter material. 
         [0054]    Outer casing  120  may be made of steel or a variety of materials, including but not limited to other metals, such as brass, galvanized steel, aluminum and iron, or other materials such as plastic, synthetic polymers or any material which is rigid and preferably resistant to corrosion. The material used can also be painted to help make them more resistant to corrosion, and to reduce the likelihood of having foreign substances, such as debris and contaminants, stick to the surfaces of outer casing  120 . The thickness/gauge of the particular material used for fabrication can also be varied. 
         [0055]    The device further comprises a first filter  140  to remove contaminants found in storm water runoff, including both soluble and insoluble contaminants. The first filter  140  may be a material such as X-TEX®, produced by the Xextex Corporation USA, which is a non-polar, lipophilic, hydrophobic media that filters and removes oil, oil sheen and sediment from water. The specific type of filter used can be varied depending on the application and particular contaminants targeted. 
         [0056]    First filter  140  can be a pliable filter material easily wrapped around the inside of the perimeter wall  122  or it may a more rigid filter material sized to fit inside the perimeter wall  122 . First filter  140  can be an about rectangular shaped piece of filter fabric having a length that is about equal to the perimeter of outer casing perimeter wall  122 . Preferably, the height H of first filter fabric  140  is shorter than the height X of outer casing perimeter wall  122  to leave a portion of outer casing perimeter wall  122  uncovered towards the bottom of outer casing perimeter wall  122 . In another embodiment, first filter fabric  140  can be placed along the entire high X of the outer casing perimeter wall  122  leaving no underflow area. A piece of first filter fabric  140  can also be placed on the outer casing base  125  over any perforations therein for added filtration. It is understood that first filter fabric  140  could also be a one piece bag-type configuration so that it may line the entire interior of the outer casing  120 , including the interior surface of outer casing perimeter wall  122  and the upper surface of the base  125 . 
         [0057]    The device further comprises an interior mesh  145 . Interior mesh  145  is a cylindrically shaped wire mesh with an aperture  146  passing through its length. Preferably, interior mesh  145  is approximately the same height as the height X of outer casing perimeter wall  122  but can be smaller in height. The diameter of the interior mesh  145  is slightly smaller than the diameter of outer casing perimeter wall  122  with the first filter  140  installed thereon so that it securely but removably fits within outer casing  120  when first filter  140  is installed. In other embodiments, interior mesh  145  may include a base, flat, or pie-pan configuration, or the like. If a base is included, the base of interior mesh  145  can be constructed of a solid material or a material that has one or more perforations, such as a steel wire mesh. Interior mesh  145  may be made of steel or a variety of materials, including but not limited to other metals, such as brass, galvanized steel, aluminum and iron, or other materials such as plastic, synthetic polymers or any material which is rigid and preferably resistant to corrosion. The material used can also be painted to help make them more resistant to corrosion, and to reduce the likelihood of having foreign substances, such as debris and contaminants, stick to the surfaces of interior mesh  145 . The thickness/gauge of the particular material used for fabrication can also be varied. 
         [0058]    The device further comprises a second filter  150 , preferably a semi-rigid, self-supporting, and non-brittle filter media. The second filter  150  is a coarser material than the first filter  145 . The second filter  150  screens out larger debris and solids and helps prevent clogging of the finer first filter  145 . Second filter  150  may be made from any material that is semi rigid and that allows for the filtration of coarse and/or fine insoluble contaminants, debris and sediment. The second filter  150  may be a semi-rigid filter media such as those typically used to filter water in ponds, such as, for example the Malata® filter media manufactured by Matala Water Technology Co., LTD. The second filter  150  is positioned vertically along the inner surface of the interior mesh  145  so that its lower edge rests upon base  125  of outer casing  120 . Second filter  150  is bent in a curved configuration so as to conform to the about cylindrical shape of the inner surface of interior mesh  145 . Preferably, the height of second filter  150  is smaller than the height of interior mesh  145  but greater than the difference between the height X of outer casing perimeter wall  122  and the height Y of the inner casing perimeter wall  132 . An additional piece of second filter  150 , may also be positioned along base  125  of outer casing  120  so as to partially or completely cover base  125 . 
         [0059]    The device further comprises an inner casing  130  comprising an about cylindrically shaped sleeve having a perimeter wall  132  and a collar  131  at one end. In the preferred embodiment, the inner casing perimeter wall  132  is solid without perforations and without a base. The inner casing  130  has aperture  134  running through its length. The outside diameter of the perimeter wall  132  of inner casing  130  is smaller than the diameter of the installed interior mesh  145 , with the difference between the two diameters being about equal to the thickness of the second filter  150 . The collar  131  on the inner casing  130  is configured in an outwardly direction away from its middle such that it will securely rest on the collar  121  of the outer casing  120  on which it will be installed. The height Y of the inner casing perimeter wall  132  is less than the height X of the outer casing&#39;s perimeter wall  122 . Collar  131  includes aperture  134  which passes through the length of inner casing  130 . The width of collar  131  is configured such that it fits within adapter ring  110  and rests on the upper surface of outer casing collar  121 . Although the current embodiment features a cylindrically shaped inner casing  130 , inner casings of various shapes and sizes can also be used depending on the particular application and the configuration of outer casing  120 . The perimeter wall  132  may be tapered so that its diameter is larger toward its top (collar side) and smaller at its bottom. 
         [0060]    In the embodiment shown, the inner casing  130  has a solid perimeter wall  132  having no openings or perforations. In other embodiments such as those shown in  FIGS. 10-11 , the inner casing  130  can be configured similar to the outer casing  120  in a basket-type configuration with a mesh type perimeter wall  122 . Alternatively, the inner casing perimeter wall  132  could include one or a plurality of opening(s) allowing for the flow of liquids through inner casing perimeter wall  132 . 
         [0061]    In the embodiment shown, the height Y of inner casing perimeter wall  132  is less than the height X of outer casing perimeter wall  122 . The difference in height between the two perimeter walls provides an open flow area under inner casing  130 , through second filter  150 , through internal mesh  145 , through first filter  140  and through outer casing  120 . The height Y of inner casing perimeter wall  32  can be varied to decrease or increase flow rates of the device. 
         [0062]    In another embodiment of the invention, the internal casing  130  further includes one or more screens within it to collect different sized debris in a sieve like fashion. Internal grills may be flat or conical in shape and may be positioned at the top, middle or bottom. Internal grills may be constructed of a material such as a steel wire mesh allowing for water to flow through the grill(s) while larger debris and sediment is retained on their upper/proximal surface(s). Internal grills can also be used to support additional filter materials, allowing for greater levels of filtration. 
         [0063]      FIG. 7  shows the intended path of fluids through the assembled device. Water (for example, contaminated surface water runoff from a gas station) travels through the perforations of the manhole cover  107  into the device to the second filter  150 . Any sediment, debris and contaminants that are too large to pass through second filter  150  collect on the second filter or become embedded within the second filter. The water travels through the second filter. Depending upon the amount of water and the flow rate and hydraulic conditions, the water may travel up the exterior of the inner casing towards the top of the device. The water then travels through the internal mesh to the first filter. Any sediment, debris and contaminants not captured by second filter  150  are removed by first filer  140 . Clean water exiting the first filter  140  passes through the outer casing  120  and out of the device. A gap left between first filter  140  and the outer casing base  125  functions as an underflow unfiltered by the first filter  140 . With time, and depending on the particular application and environmental conditions, the device will fill with sediment, debris and contaminants. Once the device is filled, has a restricted flow rate, and/or the first filter fabric  140  has become saturated with contaminants, the device is serviced by emptying the built up debris and sediment and washing and/or replacing the second filter  150  and/or first filter  140  as needed. 
         [0064]    Additional components that may be included as part of device are loops, rings, notches, or similar components on outer casing  120  and/or inner casing  130  onto which hooks, chains, ropes or other extraction devices can be secured to allow for the easier installation and removal of the assembled device from adapter ring  110 . The extraction can be performed by hand or with the use of machine. Hooks may be used which pass through the inner and/or outer casing perimeter wall(s) to extract the combined casings  120  and  130 , interior mesh  145  and filters  140  and  150  from adapter ring  110  along with any sediment, containments and debris that has accumulated in the device. 
         [0065]    Although the embodiments described herein include only two casings, the invention includes devices with more than two casings to provide greater levels of filtration. Similarly, more than two filters capable of differing treatments can be used. The type of filter(s) fitted between each casing can also vary so as to allow the filtration of even more contaminants, in terms of both number and varieties. 
         [0066]    The present invention also includes a device with only a first filter and without the second filter. 
         [0067]    Another embodiment of the invention which combines/integrates the adapter ring into the outer casing is shown in  FIG. 12 . The outer casing  220  fits directly into the manhole frame (not shown) without the need for an adapter ring. The upper lip  211  on the outer casing is configured to rest on the manhole frame. The lower lip  212  is configured to receive the collar on the inner casing  230 . As in the prior embodiments, the first filter  240  is installed on the inside of the outer casing followed by the internal mesh  245 , the second filter  250 , and then the inner casing.