Patent Publication Number: US-2005123352-A1

Title: Maintenance apparatuses for permeability improvement in fluid containment basins

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application is a continuation-in-part of U.S. patent application Ser. No. 10/654,842 filed Sep. 3, 2003, now patented as U.S. Pat. No. ______, which is a continuation-in-part of U.S. patent application Ser. No. 10/083,272, filed Feb. 23, 2002, now patented as U.S. Pat. No. 6,709,199. 
    
    
     BACKGROUND OF THE INVENTION  
      A. Field of the Invention  
      The field of the present invention relates generally to systems for controlling sediment in earthen basins, such as groundwater recharge, treated wastewater disposal and flood control basins. More specifically, the present invention relates to apparatuses for maintaining or improving the permeability in fluid containment basins or systems that utilize multiple sloped ridges in the basin bottom through which fluid is desired to continually percolate. Even more specifically, the present invention relates to such apparatuses that are configured to maintain or improve the permeability of such basins without requiring fluid flow to the basins to be periodically and substantially reduced or stopped.  
      B. Background Art  
      Earthen basins are commonly used to contain water for several purposes including, but not limited to, groundwater recharge of surface water, flood control and containment of municipal, industrial and agricultural waste waters. The function of these basins often rely on, or are enhanced by, the percolation of the contained water through the bottom and sides of the basin. The percolation rate of the basin is primarily controlled by the underlying soil conditions and material and by the amount and type of sediment which has settled on the surface of the basin bottom. The sediment usually becomes the controlling element, often clogging a basin so that pumping the water or fluid from the basin becomes the only economical means of draining the basin for maintenance. The subsequent removal or mixing of this clogging sediment requires the use of light and/or heavy equipment after the basin has adequately dried. Unfortunately, the equipment typically used for basin maintenance can compact the surface material, thereby requiring additional efforts to uncompact the material and return the basin to its maximum infiltration performance levels. The challenge for fluid containment basin designers and operators has been to develop a low maintenance facility without compromising percolation effectiveness.  
      It is well known that basin percolation is at or near the maximum rate for the first several months of operation after initial basin construction or after maintenance of an existing basin because the surface of the basin has not had time to become clogged by sediment materials. The surface clogging sediment results from several sources of fines, including single cell and filamentous algae, silts and clays in the irrigation/recharge water and generated by interbasin erosion (filling and levy erosion). Over time the percolation ability of the basin decreases as the sediment forms a virtually impenetrable clogging layer. The infiltration clogging effect of the sediment is a serious concern for all industries, businesses and agencies using percolation basins. Accumulated sediments limit the percolation of water through a basin and, without routine mechanical maintenance, the clogging effect will eventually render a basin&#39;s percolation ability virtually useless. As set forth in more detail in U.S. Pat. No. 6,709,199 (the full content of which is incorporated into this text as though fully set forth herein), basin owners and operators have historically used discing, ripping, scraping and combinations thereof to control and/or remove the clogging sediment layer with varying degrees of success. If the sediment was composed of inorganic material, discing or shallow mixing is often ineffective because the near surface becomes clogged with the accumulated fine-grained material. If the sediment included sufficient organic material, discing or shallow mixing without routine deep drying cycles is ineffective because the near surface becomes clogged with anaerobic microbes. Scraping and subsequent ripping can be effective, but it is costly and is typically required at least every three years.  
      Sediments are inorganic and/or organic particles which settle on the surface of the basin during the filling and operation of the basin. The sediments are generated and accumulated via several mechanisms including: (1) release of silt and clay from the native basin material into suspension by turbulence from the filling water in a freshly maintained or newly constructed basin; (2) wave action on the basin&#39;s perimeter side slopes; (3) settling of the suspended silt and clay contained in the influent water; and (4) settling of suspended organic materials (i.e., algae and weeds) that grow in the basin. Clays and silt-clays (fines) are deposited as a thin layer on the bottom of the basin. A layer of these fines as thin as one-eighth inch has about as much resistance to infiltration as two feet of silty sands, forty feet of sugar sands and two thousand feet of clean gravel. Over time, organics may also settle to the bottom of the basin. These settled organics also affect the infiltration ability of the basin.  
      The common methods of maintaining a basin and controlling the clogging effect are expensive and time consuming. All these methods first require the basin be drained and then dried. After drying, heavy equipment is normally used to access and work in the basin&#39;s bottom. The draining process sometimes requires pumping the water from the basin when the basin&#39;s bottom is significantly clogged that water will not empty by percolation. Pumping is also used when the basin&#39;s bottom is only somewhat clogged, but time is of the essence. The “Dry and Crack” Method (also referred to as the “Chip” Method) is accomplished by allowing the basin bottom to dry and crack to form “chips” with small spaces between the chips. Although the permeability of the basin is initially substantially improved, the chips soon resettle and the small spaces are soon filled with sediment and the basin becomes clogged, requiring the basin to be re-dried, sometimes as often as twice a month. The “Shallow Mix” Method requires the basin bottom be dried longer and deeper to allow mechanical equipment, such as a tractor, to drive on the bottom and use a tool, such as a disc, spring tooth, plow or other shallow mixing device, to break-up and mix the chips with the upper surface material to disperse the thin layer of clogging sediment into the upper surface material. Although this process is more effective at temporarily improving permeability, over time the mixed layer becomes increasingly impermeable and must eventually be removed with heavy equipment, such as a paddle wheel scraper. The use of heavy wheeled equipment compacts the upper portion of the basin&#39;s bottom, which is so detrimental to percolation that it is often necessary to utilize another piece of heavy equipment, for instance a tracklayer (bulldozer) with ripping shanks, to decompact or loosen the compacted upper layer. A third method, the “Deep Mixing” Method, requires the basin bottom be dried to a moisture content that allows heavy equipment, such as a tracklayer, to drive on the bottom and use a ripping shank, perhaps combined with a slip plow, or other deep mixing device. Although also effective at temporarily improving the permeability of the basin, the deeply mixed layer will likely begin to support an active anaerobic condition that, over time, will become the clogging layer and limit the percolation rate. In addition, as with the Shallow Mixing Method, the use of heavy wheeled scraping equipment compacts the upper portion of the scraped basin bottom. The cost of routine mixing and the eventual removal of large quantities of material makes the Deep Mixing Method a very expensive means of maintaining a water containment basin and creates long term constraints.  
      Growing concerns regarding contaminants (i.e., regulated chemicals and substances) leaching into the groundwater from percolation basins has resulted in new regulations regarding the control of erosion at construction sites where surface drainage waters flow into the basins. As is well known, eroded sediments will often adsorb or bond to common contaminants and then carry those contaminants into the containment basin. In general, the Chip, Shallow Mixing and Deep Mixing methods of basin maintenance are poor methods of contaminant control because the contaminants remain in the bottom of the basin where percolation is taking place. In fact, these three methods are somewhat in conflict with contaminant control goals because the contaminants can be easily leached, with the percolating water into the unsaturated or vadose zone, then possibly into the groundwater. When contaminant control is also required of a basin, basin maintenance becomes increasingly important and more expensive. The frequently required basin draining, drying, removal of sediments and contaminants followed by the efforts to decompact the soil require significant downtime, staff and equipment. In addition, there are concerns with air dispersal of sediments and contaminants during the basin maintenance process by the creation of dust and dust particles. The conflict of percolation effectiveness versus contaminant management usually results in basins having less effective percolation characteristics and utilizing basin maintenance methods that maintain those characteristics. Concerns regarding sediment as a basin contaminant have recently required building contractors to employ expensive on-the-jobsite sediment and other contaminant containment practices and equipment.  
      One such method that is used for management of contaminants is the “Minimum Scraping” Method. This method is employed when the object of the maintenance is to remove the sediment with the minimum amount of excess (i.e., disposal) material, such as when the sediment is considered to contain contaminants that could accumulate over time and become hazardous waste or result in groundwater contamination. To maintain the basin, the basin bottom is dried sufficiently to allow equipment, such as a motor grader, to drive on the bottom and windrow the thin layer of sediment into ridges. The windrowed sediments are wetted (to limit air dispersal) then scraped up by a loader into a dump truck, or similar equipment, for removal. Unfortunately, depending on soil composition and compaction from the equipment, the basin bottom can become compacted quickly, resulting in ever decreasing percolation rates between cleanings, usually resulting in the basin having to be drained by pumping rather than by percolation, which limits the use of this method due to the availability and cost of operating pumping and heavy equipment.  
      As set forth in U.S. Pat. No. 6,709,199, the present inventor developed a sediment control system for fluid containment basins that reduces or substantially eliminates the need to completely drain fluid from the basin and the use of heavy equipment over the permeable zones of the basin. In one embodiment of that invention, the sediment control system comprises a fluid containment basin having a plurality of basin embankments enclosing a basin bottom with a plurality of ridges and furrows on the basin bottom. Each of the ridges has at least two sides, generally formed at sloped angles, and an upper area at the top of the ridge. The furrows are located adjacent and substantially parallel to the ridges such that a furrow is disposed between and bounded by a pair of ridges. The ridges are shaped and configured, such as an inverted “V” shape, to facilitate the settlement of sediment contained in the fluid into the one or more furrows. In use, the flow of fluid into the basin is reduced on a periodic basis so that wave action washes sediment off of the upper area and sides of the ridges as the water level is lowered. Although the use of wind to generate the waves is preferred, the basin can comprise a mechanism for generating the waves. After washing of the ridges, the basin is re-filled with fluid. A substantially impermeable mat of sediment can be allowed to form in the furrows to prevent migration of contaminants contained in the fluid out of the basin. With the contaminants contained in the furrows, they can be treated or, if sufficient time is available, allowed to deteriorate into harmless or less harmful components.  
      Although the use of ridges and furrows in basins combined with the wave washing method of cleaning such basins has been demonstrated to work very well, some fluid containment basins are operated or otherwise constrained so as to prevent routine water level decreases and/or to decrease the effect of natural wave washing. When basins are not routinely dewatered to allow natural wind driven wave action to migrate the sediment from the ridge areas to the furrow areas, sediment clogging of the ridges will eventually occur. The operational and/or constrained conditions may include one, or a combination of, and are not limited to, the following: 
          (1) A basin might be relatively deep and its sides relatively steep and/or the basin relatively small so that the effect of wind driven waves on exposed ridges is diminished by virtue of the decreased velocity of the wind near the basin bottom. The sides of the relatively deep basin create a “wind shadow” that can effectively dampen the wind velocity and/or create what sailors call “dirty air”. In this condition, the bottom of the basin nearest to the incoming wind direction is likely to be in the wind shadow and receive minimal wind washing effects. The bottom of the basin furthest from the incoming wind direction is much less likely to be affected by the wind shadow and therefore will likely receive effective wind washing when the ridges are exposed during declining water levels.     (2) A basin can be configured such as an intentional recreational lake, such as for boating and/or fishing, where maintaining a high water level is desired and decreasing the water level to perform routine wave washing of the ridges is undesirable. In this condition the sediment accumulates on the ridge and furrow surfaces and eventually clogs the normally permeable ridge area.     (3) A basin may be sited in an area where adequate natural wind is unavailable part or all of the year.     (4) A “high loading” basin may receive or generate relatively large quantities of organic or inorganic sediment. A basin may receive relatively high quantities of organic sediment in situations such as a municipal or industrial wastewater treatment facility water disposal/percolation basin. In such a basin, the biological oxygen demand (BOD) may be relatively high due to entrained suspended or dissolved organic particles and/or other nutrients. The suspended particles become sediment and the dissolved organic particles and/or other nutrients become “food” for microbes and/or algae that eventually settle to the basin bottom as sediment. High levels of inorganic sediment can be generated when a basin is located in a relatively dusty area and soil or other inorganic material is blown into the basin forming clogging sediment. Another type of high loading basin is a flood control catchment basin. A flood control basin often receives runoff water containing high concentrations of street debris, including dirt (such as soil, sand, silt and clay) and organic material as is found in storm runoff water. These “high loading” conditions become problematic when the basin is not routinely or adequately dewatered and effectively wind washed.     (5) A basin may be situated where infiltration rates are relatively fast, such as 5 or 10 even  30  (vertical) feet per day. These relatively high infiltration rates normally require that the basin be dewatered and wave washed much more frequently than “normal” to prevent clogging of the ridge surface. The cost efficient operation of the basin may prevent or discourage routine wave washing of the ridges by fluctuating the water levels across the ridge surface.     (6) A basin might be constrained by relatively slow infiltration rates such as half and inch per day. This condition makes dewatering a relatively slow process.     (7) The basin volume may be relatively valuable, making it undesirable to reduce flows into the basin. Such conditions exist where basins are sited in developed areas and as infiltration demand increases, basin capacity becomes increasingly scarce and valuable. In these situations operators will often elect to spend “whatever it takes” to clean basins of clogging sediment in order to maximize basin infiltration. An example of this condition is where giant pool sweep-like machines are used to dredge the bottom of a basin located in highly developed areas. The basin bottom is cleaned while the basin is in operation. The dredging operation pumps the clogging sediment to the basin&#39;s surface and to a waste basin or somehow treats the dredged flow to separate the sediment (waste) from the water.        

      What is needed are new maintenance apparatuses that are adaptable for use in “ridge and furrow” basins that are particularly configured to improve permeability of the ridges for effective percolation rates through the ridges without the need to substantially reduce the fluid inflow into and fluid level of the basin. Preferably, such maintenance apparatuses should reduce the frequency of basin maintenance, the cost of that maintenance and the need to dispose of unwanted basin materials. In addition, the maintenance apparatuses should be cost effective, minimize the amount of labor necessary for basin maintenance, reduce the amount and frequency of basin downtime and substantially prevent the air dispersal of any basin contaminants.  
     SUMMARY OF THE INVENTION  
      The maintenance apparatuses for permeability improvement in fluid containment basins of the present invention provides the benefits and solves the problems identified above. That is to say, the present invention discloses apparatuses for maintaining a fluid containment basin that reduces the clogging effect of sediments found in basin influent and, thereby, reduces the need for basin maintenance. Use of the system of the present invention reduces the frequency and cost of typical basin maintenance, the amount of labor and materials needed for maintenance, the need to dispose of unwanted basin materials and the amount of time a basin must be taken out of operation for maintenance. The system of the present invention also reduces the likelihood that contaminants will be dispersed in the air. The apparatuses provide easy and cost effective mechanisms for improving fluid containment basin permeability. In addition, the apparatuses can be used for fluid containment systems that are configured to contain and percolate fluids other than water and which percolate those fluids through mediums other than soils.  
      In one embodiment of the present invention, the maintenance apparatuses for fluid containment basins comprises a tool support frame having a plurality of structural members configured to substantially match the profile of the ridges, which are generally in the form of an inverted V-shape. The tool support frame is configured to be moved across the fluid containment basin generally above the ridges. The maintenance apparatus of the present invention can be used with a mechanism for raising and lowering the tool support frame on and off of the one or more ridges to allow the apparatus to be moved throughout the basin. One or more ridge treating tools are supported by the tool support frame. Generally the ridge treating tools are positioned below the frame and configured to interact with the surfaces of the sides of the ridges to improve the permeability of the ridges to the fluid stored in the fluid containment basin. The one or more ridge treating tools can be selected from a group including dragging tools, discing tools and grinding tools, which can also be utilized in various combinations. The discing tool can have a disc frame with flexible axle having a plurality of disc blades attached thereto to allow the blades to substantially conform to the non-planar contour of the side of the ridges. One or more support members can be attached to the flexible axle and configured to allow the axle and the disc blades to move in response to the contour of the ridges. The grinding tool can have a grinding body with a plurality of outwardly extending teeth attached thereto.  
      The tool support frame, with the ridge treating tools attached thereto, can be configured to be towed behind a conveyance device, such as a boat, having a mechanism for generating submerged wave energy, such as a motor-driven propellor. A deflector can be used to direct the submerged wave energy onto the one or more ridges and cause some of the sediment to become re-suspended in the fluid. In an alternative configuration, the apparatus for maintaining a fluid containment basin comprises just a conveyance device configured to move through the fluid containment basin and generate submerged wave energy onto the ridges. A deflector attached to the conveyance device helps direct the wave energy onto the ridges where the sediment is re-suspended in the fluid. As described above, the conveyance device can be a boat and the mechanism for generating wave energy can be the boat&#39;s motor-driven propellor. Directional stabilizing poles can be used to help keep the boat and treating tools aligned substantially above the top of the ridges.  
      Accordingly, the primary objective of the present invention is to provide maintenance apparatuses for permeability improvement in fluid containment basins having the features generally described above and more specifically described below in the detailed description.  
      It is also an important objective of the present invention to provide maintenance apparatuses for fluid containment basins that utilize wave energy, gravitational forces and/or mechanical soil disturbance to promote permeable sloped surfaces (ridges) in the basin bottom through which fluid can percolate while keeping the basin in service.  
      It is also an important objective of the present invention to provide maintenance apparatuses for fluid containment basins that allow permeability maintenance to take place without having to drain or dry the basin, thereby allowing infiltration to continue virtually uninterrupted.  
      It is also an important objective of the present invention to provide a maintenance apparatus for fluid containment basins that is used with a motor boat or like device as it moves over the top of basin to direct fluid flow downward to improve the permeability of ridges located on the basin bottom.  
      It is also an important objective of the present invention to provide a maintenance apparatus for fluid containment basins that has a frame component that is configured to be raised and lowered from ridges located on the bottom of the basin and to carry one or more mechanical devices for cleaning the surfaces of the ridges.  
      It is also an important objective of the present invention to provide maintenance apparatuses for fluid containment basins that are cost effective to make and use in fluid containment basins having a plurality of ridges and furrows located on the basin bottom.  
      The above and other objectives of the present invention will be explained in greater detail by reference to the attached figures and the description of the preferred embodiment which follows. As set forth herein, the present invention resides in the novel features of form, construction, mode of operation and combination of parts presently described and understood by the claims.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      In the drawings which illustrate the best modes presently contemplated for carrying out the present invention:  
       FIG. 1  is an end view of a fluid containment basin bottom having ridges and furrows showing use of a boat to generate submerged wave energy and a propeller wash deflector to direct the wave energy down onto the surface of the ridges to improve permeability thereof;  
       FIG. 2  is a side view of the fluid containment basin being maintained with the apparatus of the present invention shown in  FIG. 1 ;  
       FIG. 3  is a top plan view of the fluid containment basin being maintained with the apparatus of the present invention shown in  FIG. 1  with the use of two directional stabilizing poles;  
       FIG. 4  is a top plan view of the tool support and structural frame apparatus of the present invention for use in maintaining a fluid containment basin having one or more ridges therein;  
       FIG. 5  is a side view of the tool support and structural frame apparatus of the present invention shown in  FIG. 4 ;  
       FIG. 6  is an end view of the tool support and structural frame apparatus of the present invention shown in  FIG. 4 ;  
       FIG. 7  is an end view of the tool support and structural frame apparatus of the present invention shown in  FIG. 4  utilizing two types of drag tools to clean ridges located on the bottom of a fluid containment basin;  
       FIG. 8  is a side view of the tool support and structural frame apparatus of the present invention shown being pulled by a boat utilizing a propeller wash deflector to re-suspend sediments accumulated on the surface of a ridge located on the bottom of a fluid containment basin;  
       FIG. 9  is an end view of the tool support and structural frame apparatus of the present invention shown in  FIG. 4  utilizing two types of discing and grinding tools to clean ridges located on the bottom of a fluid containment basin; and  
       FIG. 10  is a side view of the tool support and structural frame apparatus of the present invention shown with a combination of drag and discing tools mounted thereto.  
    
    
     REFERENCE NUMERALS IN DRAWINGS  
     
         
           10  Maintenance Apparatus  
           12  Fluid containment basin  
           14  Basin embankment  
           16  Operational water level  
           18  Ridges  
           20  Furrows  
           22  Basin bottom  
           24  Fluid  
           26  Sides of ridges  
           27  Percolation through ridge  
           28  Compacted material (mat)  
           30  Thin sediment layer  
           32  Wind driven waves  
           34  Top of ridge  
           36  Propellor wash deflector  
           38  Boat  
           40  Boat motor  
           42  Propellor  
           44  Submerged wave energy  
           46  Propellor wash  
           48  Re-suspended sediment  
           50  First end of deflector  
           52  Second end of deflector  
           54  Directional stabilizing poles (whiskers)  
           56  Tensioning system  
           58  Connection to boat  
           60  Hinge point  
           62  Whisker contact point on ridge  
           64  Toe of slope  
           70  Tool support and structural frame  
           71  Structural frame members  
           72  Tether connectors on frame  
           74  Tethers  
           75  Tether connectors of boat  
           76  Wheels  
           78  Skids  
           90  Drag tool connecting links  
           92  Drag tool  
           94  Second drag tool  
           96  Teeth  
           100  Disc tool  
           102  Grinder tool  
           104  Hard crusty layer  
           106  Toot connecting bracket  
           108  Disc frame  
           110  Flexible axle  
           112  Disc blades  
           114  Flexible axle turnbuckle  
           116  Disc frame hinge point  
           118  Flexible axle tension spring  
           120  Flexible axle end bearing  
           122  Lateral restraints and vertical supports  
           124  Grinder frame  
           126  Grinder body  
           128  Grinder teeth  
           130  Grinder motor  
           132  Power conveyance system  
           134  Direction of frame movement  
           136  Loose crusty layer material  
       
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      With reference to the figures where like elements have been given like numerical designations to facilitate the reader&#39;s understanding of the present invention, and particularly with reference to the embodiments of the present invention illustrated in  FIGS. 1 through 10 , the preferred embodiments of the present invention are set forth below. The enclosed figures and drawings are merely illustrative of the preferred embodiments and represent several different ways of configuring the present invention. Although specific components, materials, configurations and uses of the present invention are illustrated and set forth in this disclosure, it should be understood that a number of variations to the components and to the configuration of those components described herein and in the accompanying figures can be made without changing the scope and function of the invention set forth herein.  
      Preferred embodiments of the of the maintenance apparatuses of the present invention, identified generally as  10  in the figures, is configured for use with a fluid containment basin  12  having sloped basin embankments  14 , an operational water level  16  and a plurality of ridges  18  and furrows  20  located on the basin bottom  22 , as described in U.S. Pat. No. 6,709,199 (incorporated herein). As described in that patent, sediment in the fluid  24 , such as water, will generally settle on the ridges  18  and furrows  20 . Gravitational forces will cause some of the material that settles on the sides  26  of ridges  18  to move to the basin bottom  22  in furrows  20 , keeping the permeability of ridges  18  somewhat suitable for percolation  27  of fluid  24  through the basin bottom  22  to the groundwater located below. As the heavier materials settle in furrows  20 , a mat  28  of settled sediment is somewhat uniformly distributed on the bottom  24  of basin  12 . When the normal operational water level  16  is above the ridges  18 , some of sediments in fluid  24  will settle on sides  24  of ridges  18  to form a thin layer of sediment  30  that will, over time, create a clogging layer that substantially impedes the percolation  27  of fluid  24  through ridges  18 . In normal operation of fluid containment basin  12  for wave washing, the water level is lowered from the operational water level  16  to be adjacent the sides  26  of ridges  18  such that the wind driven waves, shown as  32  in  FIG. 1 , will substantially wash the thin layer of sediment  30  off of ridges  18 , beginning with the top  34  of ridges  18 . As the water level is furthered lowered, the waves  32  will wash the lower portions of sides  26  of ridges  18 . Once the ridges  18  are substantially washed clean of sediment, the water level is raised back to or near its operational water level  16  for normal operation of fluid containment basin  12 , with the fluid  24  being able to percolate  27  through ridges  18  once again.  
      Although the wave washing technique described above and in U.S. Pat. No. 6,709,199 works well to maintain, improve and restore the permeability of a fluid containment basin  12  without the need for the use of heavy equipment in the basin  12 , some such configured basins have or are likely to experience limitations with wave washing (as set forth in the summary above). To facilitate the maintenance of fluid containment basins  12  having a plurality of ridges  18  and furrows  20  without the need to reduce fluid inflow into the basin  12 , the apparatuses  10  of the present invention can be utilized to improve and/or restore permeability to the basin  12  for the percolation  27  of fluid  24  through the ridges  18 .  
      The configuration of one such apparatus is shown in  FIGS. 1 through 3 . This particular apparatus is a propeller wash deflector  36  that is configured to be attached to a conveyance device that is driven, towed, pulled or pushed through the fluid containment basin  12 , such as boat  38  having an outboard motor  40  with a propellor  42 , either above, through or below the level of fluid  24  in basin  12 . Boat  38 , or other device, is used to generate submerged wave energy, shown as  44  in  FIG. 1 . In the embodiment where the device is boat  38 , the submerged wave energy is generated from the propeller wash  46  from propellor  42  that is directed by propellor wash deflector  36  attached to motor  40  to re-suspend the sediments, shown as  48  in  FIGS. 1 through 3 , contained in the sediment layer  30  on sides  26  of ridges  18 . The re-suspended sediment  48  will be directed to substantially re-settle in furrows  20  to accumulate in mat  28 , thereby improving the permeability of ridges  18  for the percolation of fluid  24  through the basin bottom  22 .  
      Propellor wash deflector  36  is shaped and configured to substantially envelope propellor  42  such that the force of water churned by propellor  42  during operation is directed substantially downward, as best shown in  FIGS. 1 and 2 . As shown in the figures, propellor wash deflector  36  can have a first end  50  attached to motor  40  just above propellor  42  and a second end  52  shaped to facilitate the direction of the propellor wash  46  toward the ridges  18  in basin  12 . In one configuration, propellor wash deflector has a generally cone shape. If desired, propellor wash deflector  36  can be removably attached to motor  40 . Although various materials are suitable for propellor wash deflector  36 , such as metals, plastics, composites, fiberglass and others, the preferred material is substantially corrosion resistant and strong enough to resist damage from submerged wave energy  44 .  
      Boat  38  can be configured with an operator who controls the movement of boat  38  above ridges  18  by steering the boat  38  in a conventional way. Alternatively, boat  38  can utilize one or more directional stabilizing poles  54 , also know as whiskers, to aid in the directional control of boat  38  above ridges  18 .  FIGS. 1 and 2  show the use of a single whisker  54 , whereas  FIG. 3  shows the use of a pair of whiskers  54 . On one configuration, whiskers  54  are configured to be buoyant so they will float alongside boat  38  when not in use. A tensioning system  56 , comprised of a rope or cable attached to boat  38  at tension connection  58  and hinge point  60 , is configured to lower whiskers  54  to contact side  26  of ridges  18  at contact point  62  just above the toe  64  of the slope of side  26 . In use, the tensioned whiskers  54  contact the sides  26  of the ridges  18  to prevent boat  38  from substantially moving off the centerline of ridges  18  while moving forward across basin  12 . The whiskers are raised by loosening tension system  56  to allow the buoyancy of each whisker  54  to raise it to the surface of fluid  24 .  
      Another maintenance apparatus  10  for use in improving permeability of a fluid containment basin  12 , configured as described above, is shown in  FIGS. 4 through 10 . In this configuration, apparatus  10  comprises a tool support and structural frame  70 , comprising a plurality of structural frame members  71  in an inverted V-shape (i.e., with an interior profile similar to ridges  18 ), that is configured to support and carry a variety of ridge treating tools for disturbing the thin ridge surface sediment  30  on sides  26  of ridges  18  to re-suspend the sediment  48  and facilitate it settling in furrows  20  to accumulate in the settled sediment in mat  28 . In the above-described configuration, frame  70  is configured to match the profile of ridge  18  and support the ridge treating tools in a like profile. In another configuration, frame  70  can be configured in a non-matching shape, but support the ridge treating tools in corresponding relationship with the profile of ridge  18 . As best shown in  FIGS. 4 and 5 , frame  70  has one or more attachment points or tether connectors  72  for attachment to tethers  74  that connect frame  70  to the aft of boat  38  at tether connectors  75  (shown in  FIG. 8 ) on boat  38 . Attachment points  72  can be utilized to connect frame  70  to other mechanisms that can be utilized to raise frame  70  and various ridge treating tools attached thereto, as set forth in more detail below, off of ridge  18  to allow frame  70  and the tools to turn and move from one ridge  18  to another without the hindrance of dragging and disturbing furrows  20 , such as between pairs of ridges  18 . The propeller wash  46 , together with gravity and underwater currents, move the re-suspended sediments  48  toward and into mat  28  in furrows  20 . Boat  38  can be operated at various speeds and power settings to accomplish good re-suspension of the thin ridge surface sediment  30  on ridges  18 .  
      Structural frame  70  can be attached to tensioning cables or to other devices that can be utilized to allow one side or one end of frame  70  to be raised or lowered as needed to adjust for the configuration of ridges  18  and the amount of downward pressure (weight) desired. Such a device can be configured to travel on or above the basin bottom  22  and/or could be configured to provide the motive force for moving structural frame  70  along basin bottom  22  and making the turns or directional changes to allow structural frame  70  to come in contact with more than one ridge  18  in the basin  12 . Structural frame  70  can also be supported by wheels  76  and/or skids  78 , as best shown in  FIGS. 4 through 10 . Wheels  76  and/or skids  78  are normally in contact with the furrows  20  adjacent to ridges  18 , however, wheels  76  and/or skids  78  can also or exclusively be in contact with ridges  18 . Wheels  76  and/or skids  78  can be controlled and/or adjusted to provide variations in height between structural frame  70  and the treating tools attached thereto and the surface of ridge  18 .  
      Structural frame  70  is comprised of a plurality of structural frame members  71  configured as desired to accomplish the objectives set forth herein. Structural frame members  71  can be virtually any size and/or shape, depending on the configuration chosen for structural frame  70 , that are utilized as frame members, including but not limited to square, rectangular, round L-shaped, C-shaped, H-shaped, tubular and other types of frame members. Structural frame members  71  can be of a variety different materials, including steel, aluminum, fiberglass, plastics and composite materials. Materials chosen for structural frame members  71  should be appropriate for use in the fluids stored in basin  12 . If necessary, structural frame members  71  can be treated, coated, covered or otherwise protected from corrosion or other damaging effects of the fluid.  
      As set forth above, various ridge treating tools can be utilized with frame  70 , including dragging, discing and grinding tools. In a preferred embodiment, the ridge treating tools are supported by frame  70  in corresponding relationship with the profile of ridge  18 . The dragging tools can be connected to frame  70  by way of connecting links  90 , shown in  FIGS. 7 and 8 . Various drag tools can be used with frame  70  and they can be mixed together, such as shown in  FIG. 7 , to disturb the thin ridge surface sediment  30  on sides  26  of ridges  18  so as to cause the sediment  30  to become re-suspended and move into furrows  20 . One such drag tool, shown as  92  in  FIG. 7 , can be configured similar to chain link material or expanded metal. A second drag tool, shown as  94  in  FIG. 7 , can also be configured similar to chain link material or expanded metal with a plurality of downward extending protrusions or teeth  96  that are configured to pass through, and more aggressively disturb, the thin ridge surface sediment  30  on sides  26  of ridges  18 . Both drag tools  92  and  94  are configured to re-suspend the sediment material to facilitate it moving into furrows  20  and settling into mat  28 . The use of the drag tool connecting links  90  allow the drag tools  92  and  94  to move across the side  26  of ridges  18  somewhat independent of frame  70 . Drag tools  92  and  94  should be configured to be heavy enough to provide good contact with side  26  of ridge  18  and disturb the thin ridge surface sediment layer  30  on ridge  18 . If desired, additional weight can be added to drag tools  92  and  94  to provide additional contact with ridge  18 . As an example, additional weight can be achieved by attaching lengths of flexible metal chain or other weighted materials to the top side of drag tools  92  and  94 . The propellor wash  46  directed from propellor  42  by propellor wash deflector  36  separates the fine sediment from the course grain material generally utilized for ridge  18 . The fine sediment is re-suspended and the sands fall back onto the side  26  of ridge  18 . The propellor wash  46 , together with gravity and underwater currents, moves the re-suspended sediments  48  toward and into mat  28  at the bottom of furrows  20 . As explained above, frame  70  can be more or less weighted to adjust the drag force of tools  92  and  94  and boat  38  can be operated at various speeds and at various power settings to accomplish good suspension of the thin ridge surface sediment  30  on sides  26  of ridges  18 .  
      As shown in  FIG. 8 , boat  38  having motor  40  with propellor  42  can pull, via tethers  78 , the tool support and structural frame  70  with drag tool  92  and/or drag tool  94 . The drag tools  92  and  94  disturb the thin sediment layer  30  on side  26  of ridge  18  and the propellor wash  46 , as directed downward by propellor wash deflector  36 , create re-suspended sediments  48 .  FIG. 8  is a side or elevation view of drag tool  94  being dragged across the side  26  of ridge  18  on which is located the thin sediment layer  30 . The drag tool  94 , which could be drag tool  92  or similar dragging tools, are displacing the thin ridge surface sediment layer  30  and causing most of the sediment to become re-suspended sediment  48 . The propellor wash  46  creates a significant underwater wave action that aids in re-suspending the thin ridge surface sediment  30  and moving the sediment toward and into furrow  20 , where the re-suspended sediment  48  settles into mat  28  at the bottom of furrow  20 . Tethers  74  attach frame  70  to boat  38  to allow frame  70 , and the dragging tools  92  and  94  attached thereto by connecting links  90 , to be moved along ridge  18 . The whiskers  54  are held against the whisker point of contact  62  on ridge  18  by tensioning system  56 , providing directional stabilization of boat  38 , frame  70  and tools  92  and/or  94 .  
      As stated above, tool support and structural frame  70  of the present invention can also be utilized to support and carry disc and grinding tools to mechanically treat sides  26  of ridges  18  to increase the permeability thereof. As shown in  FIG. 9 , frame  34  can support disc tool  100 , shown on the left side of frame  70  and ridge  18 , and grinder tool  102 , shown on the right side of frame  70  and ridge  18 . As with the dragging tools  92  and  94 , disc tool  100  and grinder tool  102  are attached to frame  70  so as to interact with sides  26  when frame  70  is substantially centered over the top  34  of ridge  18 . Typically, the same type of tool, e.g. disc tool  100  or grinder tool  102 , will be used on both sides  26  of ridge  18  at the same time, depending on the need and the operator&#39;s discretion. Disc tool  100  and grinder tool  102  are used when the thin sediment layer  30  on sides  26  of ridge  18  become significantly compacted or hardened, such that it forms a hard crusty layer, shown as  104  in  FIGS. 9 and 10 , on the side  26  of ridge  18 . Hard crusty layer  104  is likely to form where the basin  12  is deep enough to cause the fluid pressure at the bottom  22  of basin  12  to be sufficiently high to compress the thin ridge surface sediment layer  30  into a hard crusty layer  104 . Disc tool  100  is used to cut through the hard crusty layer  104  and into the surface of side  26  of ridge  18  to more thoroughly expose the thin ridge surface sediment  30  to the action of the propellor wash  46  and to the gravitational and underwater current forces. Grinding tool  102  is used to more thoroughly cut and grind the hard crusty layer  104  on surface of side  26  and into ridge  18  when the crust has become particularly hard. Frame  70  has one or more tool-connecting brackets  106  to support the disc tool  100  and grinder tool  102 .  
      As shown in  FIGS. 9 and 10 , disc tool  100  is constructed to have a disc frame  108  supporting a flexible axle  110  that allows the independently rotatable disc blades  112  to effectively contact the hard crusty layer  104  on the surface of sides  26  of ridges  18  even when the surface of ridge  18  is non-planar. As is known to those skilled in the art, the surface of sides  26  of ridges  18  often become more or less “rounded” over time. Generally, an axle that is rigid would not provide the required flexibility. Flexible axle  110 , which can be a cable or cable-like member, is tensioned to disc frame  108  by at least one tensioning device, such as turnbuckle  114 . In the embodiment shown in  FIG. 9 , one end of disc frame  108  is hinged at the disc frame hinge point  116  and a flexible axle turnbuckle  114  is used to provide preset adjustable tension. This embodiment also utilizes a flexible axle tension spring  118  that provides variable tension to flexible axle  110 . Flexible axle  110  is connected to the disc frame  108  by a flexible axle end bearing  120 . To provide lateral (i.e., to the rear of disc frame  108 ) and vertical support for the disc tool  100 , lateral restraints and vertical support members  122  are utilized. These lateral restraints and vertical support members  122  allow flexible axle  110  and disc blades  112  to move vertically to conform to the non-planar and rounded shape of the side  26  of ridge  18 . Lateral restraints and vertical supports  122  also provide some downward pressure to aid disc blades  112  in cutting through the hard crusty layer  104  on the ridge surface. As shown in  FIG. 10 , disc tool  100  can be attached to frame  70  such that it is in a non-perpendicular relationship with frame  70  to better facilitate operation of disc tool  100 . In one configuration, disc frame  108  and/or disc blades  112  can be arranged such that as the disc blades  113  cut into ridge  18  the ridge material is pushed up the sides  26  to essentially “re-build” ridge  18 .  
      Grinder tool  102  includes grinder frame  124  attached to and supported by tool and structural frame  70  and a grinder body  126  having a plurality of grinder teeth  128  thereon for cutting into the hard crusty layer  104  on sides  26  of ridge  18 . Grinder tool  102  can also be made flexible, without the concerns for the lateral support disc tool  100  requires. The rotating motion of grinder tool  102  may be powered by the friction between the side  26  of ridge  18  or by a grinder motor  130 . If utilized, grinder motor  130  is connected to a power source by a power conveyance system, such as wires or hydraulic hoses  132 . Disc tool  100  and grinder tool  102  will generally be configured to be sufficiently heavy enough to provide a good contact with side  26  of ridge  18  and cut through the hard crusty layer  104  and/or thin sediment layer  30  and into ridge  18  itself. In operation, grinding tool  102  will crush and pulverize the hard crusty layer  104  and thin sediment layer  30 .  
      The tool support and structural frame  70  shown in  FIG. 10  has drag tool  92  and disc tool  100  atop a ridge  18  being pulled in the direction shown as  134 . As shown in  FIG. 10 , disc tool  100  is cutting into the hard crusty layer  104  on side  26  of ridge  18  to move the loose crusty ridge material, shown as  136 , downward, thereby breaking, disturbing and mixing material  136 . Drag tool  92  is further disturbing the mixed material and the deflected propellor wash  46  is helping to create re-suspended sediments  48 , which will migrate into furrows  20  and collect as additional mat  28 . Those skilled in the art will recognize that disc tool  100  can be replaced by grinder tool  102  and/or drag tool  92  can be replaced with the second drag tool  94  having teeth  96 .  
      Those skilled in the art will also recognize that the use of boat  38  is only descriptive of one embodiment of the apparatus  10  of the present invention. Other embodiments, which may be more or less preferred depending on the configuration of basin  12  and other factors, may include the use of tensioning devices, such as ropes or cables, that are controlled at each end of basin  12  and attached to apparatus  10  so as to move apparatus  10  across basin  12  to disturb the thin ridge surface sediment layer  30  and/or the hard crusty layer  104  on side  26  of ridge  18 . Another embodiment may include a self-contained or remote controlled device used to move apparatuses  10  through basin  12  above ridges  18  to disturb the thin ridge surface sediment layer  30  and the hard crusty layer  104  on the surface of side  26  of ridge  18 . The apparatus  10  used with these devices can include a mechanism for creating submerged wave energy  44 , similar to that created by the deflection of propellor wash  46  by propellor wash deflector  36 , or a device for moving tool support and structural frame  70 , with drag tools  92  or  94 , disc tools  100  and/or grinder tools  102  supported thereon, across basin  12  substantially centered over ridge  18 .  
      While there are shown and described herein certain specific alternative forms of the invention, it will be readily apparent to those skilled in the art that the invention is not so limited, but is susceptible to various modifications and rearrangements in design and materials without departing from the spirit and scope of the invention. For instance, it should be noted that the present invention is subject to modification with regard to the dimensional relationships set forth herein and modifications in assembly, materials, size, shape and use. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.