Abstract:
Embodiments of a multipurpose groundwater sampler device are shown and described, each having a sample tube part of which forms a sample chamber, a top portion having a handle, a novel inlet portion, a sediment trap, novel valve means and a means to join the assembly together. The novel inlet portion is of a size and shape that facilitates rapid filling of the sample chamber and facilitates the collection of layers of fluid which can be measured in the sample chamber to directly represent the in situ thickness of a stratified layer. The novel valve means also facilitates fast filling and incorporates a sediment trap, which keeps sediments from interfering with the valve workings. The multipurpose groundwater sampler device of the present invention is adapted to be provided with an extension tube of the same inside opening as the sample chamber to extend the wide inlet a greater distance from the valve means for collecting thick layers of stratified liquids at their in situ thickness. A novel valve means is disclosed for adaptation to the top portion to prevent the sample chamber from overfilling. The multipurpose groundwater sampler device, may be provided with discharge means to accommodate emptying the sampler.

Description:
RELATED APPLICATIONS 
     The inventor hereof claims priority based upon and pursuant to provisional patent application serial No. 60/092,296 filed on Jul. 10, 1998. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to groundwater contamination sampling systems; and, more particularly, to an apparatus for quickly, accurately, sampling groundwater and accurately and efficiently sampling groundwater where soil sediments or floating contaminants may be present. 
     BACKGROUND OF THE INVENTION &amp; DESCRIPTION OF THE PRIOR ART 
     The process of testing groundwater for contamination may be time consuming, expensive, and environmentally unfriendly. Because the results are used to determine future monitoring and/or remediation efforts for which cost can run into millions of dollars, the sampling requires precision. Often it is desirable to retrieve an adequate quantity of chemically and stratigraphically representative samples for analysis. The analysis may include determination of the thickness of a layer of contamination floating on the groundwater surface. 
     The multipurpose groundwater sampler allows samples to be acquired faster and more efficiently, with less sample loss or interference from sediments and solids and it is quickly field adaptable to retrieve accurate, representative samples of floating contaminant thickness. In accordance with the technique of groundwater sampling, devices of the prior art called bailers are used to retrieve groundwater samples from wells penetrating the water table beneath the ground surface. A bailer consists of a hollow tube with an inlet nozzle and a check valve means at the lower end, and a handle at the top. The bailer is lowered by tether into the well so as to intersect the water table, and fill with water through the bottom nozzle and valve means. The bailer is retrieved to provide a representative water sample for visual and laboratory analysis. 
     Groundwater sampling bailers of the prior art are commonly produced and sold by a number of manufacturers. These bailers all have certain design features in common which render them inefficient for their intended purpose of sampling groundwater and unreliable for certain other purposes for which there is a concurrent need, such as obtaining a representative thickness of a contaminant, gasoline being an example, floating on the groundwater surfaces. Technicians who use the bailers complain that they fill too slowly and that sediments normally found in the water being sampled cause the devices to leak excessively. Because monitoring sites are remote from a technician&#39;s facility, they often complain about the number and amount of equipment they have to carry to complete their sampling. 
     Voss Technologies produces and sells a makeshift, add-on device for their standard water sampling bailers for those attempting to obtain a sample of floating petroleum contaminants. The device sold by Voss however, has several apparent drawbacks. That device is a separate part which must be purchased, inventoried, brought to the job site, and adapted to a standard bailer. The adapter does not have a means for keeping sediments away from the valve, the adapter has been known to fall off in the well during use, resulting in great expense of time and money attempting retrieval. Further, the device is physically constrained with a fixed distance between the restrictive valve and the fluid inlet with no provision for extending the length in the field to accommodate thicker contaminant layers. 
     All the groundwater sampling bailers heretofore known suffer from a number of disadvantages and drawbacks: 
     a) They are made specifically for the one purpose of retrieving a sample of water from below the static water surface. In addition to retrieving a water sample, field technicians often are required to retrieve and measure a representative thickness of floating contaminants such as gasoline. Because it is inconvenient and expensive to carry a multitude of different sampling equipment to each site, technicians attempt to use water-sampling bailers to retrieve a sample of representative thickness of liquids that float on the groundwater surface. Bailers of the prior art are not effective for this purpose because the fluid inlet nozzle is much smaller in diameter than the sample chamber into which the sample is collected. Known bailers of the prior art have nozzle inlet openings of about one half inch in diameter or less to fill a one and one half inch diameter sample chamber. When a bailer with a one half inch diameter nozzle is used to sample a liquid with one inch of stratified contaminant thickness in situ, the bailer will allow less than less than one quarter inch thickness of this layer to accumulate in a one and one half inch diameter sample chamber. The small opening also creates an aerodynamic shape which causes liquids to flow preferentially around the nozzle instead of into the nozzle as the device is lowered into the liquid to be sampled. The thickness of the sample in the sample chamber therefore, is not representative of the fluid thickness in the well. 
     b) A low cost and reliable device isn&#39;t available for retrieving a representative thickness of floating contaminant as well as a representative water sample. 
     c) Where attempts have been made to provide an adapter to a standard bailer to provide a wider inlet, the attempts have produced devices with inconvenient and expensive add on accessories that can be forgotten or lost and which require the user to know in advance of sampling whether or not the device will be needed., additionally, the add on parts can and do fall off in the well. 
     d) They fill slower than desired. The small fluid inlet nozzle and its configuration restricts water flow into the sampler such that only a small volume of fluid enters the nozzle relative to the rate of penetration of the sampler through the contaminant and the device fills slower than desired. Frequently, the small diameter, fluid inlet nozzle facilitates the formation of a meniscus across the nozzle that further restricts the flow of water into the sampler. 
     e) The exteriors are aerodynamically designed having a tapered or dome shaped bottom that is small at the inlet nozzle, becoming larger at the exterior of the sample chamber, as a result, fluids tend to flow preferentially around the outside of the sampler as it is lowered rather than enter the small fluid inlet nozzle. Layers can be missed and sample time is increased. 
     f) All existing bailers rely on a one way check valve to let fluid in but not back out. Most bailers of the prior art utilize a ball check, valve, others a flapper or pop-it for this valve, which is located at the extreme bottom of the interior of the sampler. All bailers of the prior art have the valves located at the extreme bottom of the sample chamber. Sediments and solids normally present in the water sample settle out of suspension to the lowest point in the sample chamber where they interfere with the workings of the valve. This condition is made worse in bailers where balls serve as valves, by plugging an inlet hole because the ball rests in the small end of a cone shaped holder which funnels and concentrates sediments directly to the area where the ball is expected to produce a seal. The solids and sediments become trapped under and around the ball, propping it away from its mating sealing surface and causing it to leak excessively, resulting in loss of sample and the need for subsequent re-sampling. Further, the excessive leaking causes potentially contaminated fluid to be released into the surrounding environment or splash the user, which may cause harm. 
     g) Floating contaminants can be lost out the open tops of the bailers if the technician lowers the bailer below the top surface of the water in the well. Bailers of the prior art that utilize a standard check valve at the top of the sample chamber do not address this problem because the valves are in-line and open in the same direction. Fluid flowing in from the bottom can flow right out the top, therefore continued lowering over fills the bailer. Since the device is usually out of sight at some depth, the technician cannot always know when the chamber is full, but not too full. 
     h) By their nature, valves used to scal the sample chamber of bailers are restrictive to flow. That is, the passageway through which water flows from the well to the sample chamber is smaller than sampler itself, the inlet, and the sample chamber. Those skilled in the art of valves and fluid flow recognize that valves of this type further create physical impediments to water flow. Bailers of the present art are limited in capability because they are constructed with a fixed distance between the fluid inlet and the restrictive valve. The thickness of floating contaminants can vary greatly from well to well. when the contaminant is a thicker layer it will reach the valve restriction before the full thickness is entrapped. The restriction causes the fluid to enter more slowly while the sampler continues descending at the same rate, thereupon pushing aside some of the sample rather than collecting it. Prior art, including add on devices, do not provide a means for the user to make changes in the field to increase the distance between the fluid inlet and the valve restriction to allow a representative thickness of the floating contaminant to enter and be trapped in the sampler prior to its reaching the valve restriction. 
     It is readily apparent that an improved and multipurpose groundwater sampler is needed to overcome the drawbacks apparent in the prior art and to render more a reliable, convenient, and cost effective method of sampling groundwater and floating liquid thickness. It is, therefore, to the provision of such an improved multipurpose groundwater sampler that the present invention is directed. 
     OBJECTS AND ADVANTAGES 
     Accordingly, the several objects of the present invention are: 
     a )to provide a multipurpose groundwater sampler that causes solids and sediments to be channeled and collected away from the valve means; 
     b) to provide an improved multipurpose groundwater sampler that provides flexibility of use for the multiple purposes of groundwater sampling and for obtaining representative sample thickness of floating contaminants 
     c) to provide an improved multipurpose groundwater sampler with fewer parts than makeshift attempts at adaptation for multiple purposes; 
     d) to provide an improved multipurpose groundwater sampler that fills rapidly; 
     1) to provide an improved multipurpose groundwater sampler that is designed for efficient flow into the sampler instead of around the outside of the sampler. 
     e) to provide an improved multipurpose groundwater sampler that can be used to accurately recover a representative thickness of floating liquid; 
     1) to provide an improved multipurpose groundwater sampler with an inlet opening nearly the same diameter as the sample chamber 
     2) to provide an improved multipurpose groundwater sampler that provides field adaptability for extending the distance from the fluid inlet to the valve means to trap the floating product at its original thickness before the sample reaches the valve means; 
     3) to provide an improved multipurpose groundwater sampler that readily allows the addition of extension tubes of any length below the valve means 
     4) to provide an improved multipurpose groundwater sampler for retrieving representative thickness of thin layers of floating contaminants without add on pieces. 
     f). to provide an improved multipurpose groundwater sampler that can be configured with a floating ball check means at the top to prevent samples from escaping out the top, yet readily fills. 
     I) to provide an improved multipurpose groundwater sampler that is economical to manufacture; 
     j) to provide an improved multipurpose groundwater sampler that is reusable for multiple sampling, yet may also be disposable at the end of its service life. 
     Other objects, features and advantages of the present invention will become apparent to those skilled in the art by reference to the drawings and to the detailed description of the preferred embodiment presented herein. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with the several objects of the present invention, disclosed is a multipurpose groundwater sampling device having a novel fluid inlet, a novel valve means incorporating an inverted funnel, an elevated valve means on a pedestal structure, a sediment trapping means, an extended wall shank to accommodate an extension inlet tube as an optional feature, a mid portion to contain the sample, a top portion having a handle and a large opening which serves as a pour spout, an optional top portion incorporating a floating valve means, and means to join the assembly together. 
     The multipurpose groundwater sampler of the present invention is designed to be provided with an optional extension inlet tube of variable length, which can readily be attached to the device in the field, and in which to secure the entire thickness of a floating liquid prior to the liquid reaching the restrictive valve means. The multipurpose groundwater sampler may be provided with weights to overcome any tendency toward buoyancy. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is better understood by reading the Detailed Description of the Preferred Embodiments with reference to the accompanying drawing figures, in which like reference numerals denote similar structure and refer like elements throughout, and in which: 
     FIG. 1 is a perspective view of the Multipurpose Groundwater Sampler. 
     FIG. 2 is an exploded view of the Multipurpose Groundwater Sampler of the present invention with detail. 
     FIG. 3 is a perspective view of the optional top portion with a floating valve means. 
     FIG. 4 is a perspective view of the optional extension tube. 
    
    
     It is to be noted that the drawings presented are intended solely for the purpose of illustration and that they are neither desired nor intended to limit the invention to any or all of the exact details of construction shown, except insofar as they may be deemed essential to claim the invention. 
     REFERENCE NUMERALS IN DRAWINGS 
       10  Multipurpose Groundwater 
       11  sample tube 
       20  valve means structure 
       21  flange 
       22  lower tapered edge 
       23  tower extended wall, shank 
       24  shoulder 
       25  upper extended wall, shank 
       26  upper tapered edge 
       27  shoulder 
       28  fluid inlet 
       29  inverted funnel 
       30  valve means fluid outlet 
       31  inverted funnel base 
       32  valve means seat 
       40  extension tube 
       50  ball 
       55  sample chamber 
       60  weight means 
       70  top portion 
       71  handle 
       72  pour spout 
       73  extended wall, shank 
       74  tapered edge 
       75  shoulder 
       76  fluid inlet 
       80  optional top portion 
       81  handle 
       82  extended wall, shank 
       83  tapered edge 
       84  pour spout 
       86  upper ball seat 
       90  floating ball 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In describing preferred embodiments of the present invention illustrated in the figures, specific terminology is employed for the sake of clarity. The invention however, is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. 
     Shown in FIG. 1 is the preferred embodiment of the multipurpose groundwater sampler  10  of the present invention. In that figure the multipurpose groundwater sampler  10  is shown oriented vertically, that being the principal axis of the sampler while in operation according to its intended use. 
     In the exploded view of the preferred embodiment shown FIG. 2, the central portion of the multipurpose groundwater sampler  10  is a thin wall, hollow tube or sample chamber  11  of circular cross section. In the preferred embodiment shown in FIG. 2, tube  11  is approximately 1.60 inches in outside diameter and approximately 1.50 inches inside diameter and approximately 36 inches long and is manufactured from extruded High Density Polyethylene (HDPE). At the base of tube  11  as it is shown in FIG. 2, is an appropriately dimensioned novel valve means structure  20 . It will be recognized by those skilled in the art of groundwater sampling that the diameter, wall thickness and length are selected with consideration to the structure in which they are placed and the volume of sample required and that the material of manufacture is selected on the basis of chemical compatibility with and nature of the contaminant being sampled, and the structural requirements. Therefore the physical dimensions and the materials of construction may be varied to provide a sampler which fits the intended use. 
     Valve means structure  20  shown in FIG. 2 is approximately 1.5 inches long, which may vary in proportion to the size of tube  11  with which it is used. Valve means structure  20  shown in the preferred embodiment can be produced as a distinct unit by injection molding, stamping, or machining or as an assembly of separate parts. Alternately, the novel valve means structure  20  may formed into the structure of the main tube body itself by molding or other means. 
     The exterior of novel valve means structure  20  consists of a generally cylindrical upper extended wall or shank portion  25 . The top tapered edge  26  is beveled on the exterior to facilitate insertion of shank  25  into tube  11 . The outside diameter of shank  25  is approximately the same dimension as the inside diameter of tube  11  to produce a strong interference fit between tube  11  and shank  25  of the valve means structure  20 . A shoulder portion  24  is provided to offset the shank  25  from the flange  21  and against which sample chamber  11  abuts when assembled. The connection between the tube  11  and shank  25  produces a watertight fit. O rings, plumbing tape, or other sealant may be utilized to produce a seal as well. The embodiment of the present invention illustrated in FIG. 2 is assembled by inserting extended wall portion  25  into sample chamber  11  for an interference fit and then heat welding for strength. It will be recognized by those skilled in the art of mechanical connections, however that other mechanical means, such as clamping, screwing, riveting, sonic welding or other means may be utilized in lieu of a friction fit and heat welding. 
     Shown in FIG. 4 is a generally cylindrical, lower or shank  23  suitable for adaptation to a novel extension tube  40  of the same inside diameter as sample chamber  11  is provided. The bottom leading edge  22  is beveled on the exterior to facilitate insertion of shank  23  into extension tube  40 . The outside diameter of lower shank  23  is approximately the same dimension as the inside diameter of extension tube  40  to produce a strong interference fit between extension tube  40  and lower extended wall shank  23  of valve means structure  20 . A shoulder portion  24  is provided to offset the lower extended wall shank portion  23  from flange  21  and against which extension tube  40  abuts when assembled. The connection between extension tube  40  and lower shank  23  produces a watertight fit. O rings, plumbing tape, or other sealant may be utilized to produce a seal as well. Extension tube  40  is secured in place by the friction fit or, alternatively, heat welding, clamping, screwing, riveting, sonic welding, or other means of mechanical attachment can be performed at spots along the circumference where tube  11  overlaps shank  25 . 
     Novel valve means  20  contains fluid inlet  28  located at the bottom of valve means assembly  20 . Fluid inlet  28  of the preferred embodiment in FIG. 2 is circular in cross section, concentric to tube  11 , and has an inside diameter of nearly the same dimension as the inside diameter of tube  11 . The diameter of the fluid inlet opening is a minimum of fifty percent the diameter of the inside diameter of the sample chamber Fluid inlet  28  of the preferred embodiment in FIG. 2 has an inside diameter of approximately 1.375 inches. Optional extension tube  40  has an inlet diameter and interior diameter exactly the same as inside diameter of tube  11  sample chamber. The inlet diameter will change according to the diameter of tube  11  used, the material of manufacture, and the structural requirements of the use. 
     Valve means structure  20  has an internal fluid passageway oriented along the long axis of and concentric to the diameter of valve means structure  20  such that fluid entering at fluid inlet  28  is conducted through the internal passageway to valve means outlet  30 . The interior passageway is circular and concentric to tube  11  at all points along its length. The interior diameter remains consistent at approximately 1.375 inches for a distance of approximately 0.625 inches from fluid inlet  28  toward fluid outlet  30 . Beginning at a distance of 0.625 inches from fluid inlet  28 , the diameter of the passage varies in inverse proportion to the distance from fluid inlet  28  such that the passageway narrows to produce the shape of an inverted funnel  29 . Inverted funnel  29  has its largest diameter near fluid inlet  28  and its smaller diameter pointing upward to form valve means outlet  30 . The base of inverted funnel  29  is joined to the interior wall of valve means structure  20  circumferentially at approximately the mid point of the long axis of valve means structure  20 . The surface of the inverted funnel  29  creates a barrier between the upper interior of valve means structure  29  and the lower interior. 
     The upper portion of inverted funnel  29  is truncated by a circular opening approximately 0.6875 inches in diameter, concentric with tube  11  and which is valve means outlet  30  from the valve means passageway. Valve means outlet  30  at the top of funnel  29  is located vertically above the base of inverted funnel  29 . Inverted funnel  29  thus positioned, functions as a pedestal which serves to elevate check ball  50  or other valve means closure mechanism above the bottom of the interior of tube  11  sample chamber. The top of inverted funnel  29  which forms fluid outlet  30  is beveled inward toward the opening around the entire valve means opening circumference, according to a formulae known in the art of valve seals and seats, to produce a valve means seat  32  against which a spherical ball  50  or other stopper, plug, or other valve means can fit to create a one way seal. Spherical ball  50  shown in the preferred embodiment of FIG. 2 is made of a suitably inert material having a specific gravity greater than the fluid to be sampled, and has a diameter of 0.75 inch, sized in accordance with known principles for utilizing a ball to plug the opening at the top of a circular opening such as in valve means outlet  30 . The preferred embodiment shown in FIG. 2 utilizes ball  50  to plug the opening, however it will be readily apparent to those skilled in the art of valves that other manner of sealing devices including flappers and pop-its serve the same purpose. 
     In the preferred embodiment shown in FIG. 2, the distance from valve means seat  32  to the inside wall of shank  25  of valve means structure  20  is determined by the novel formula to be equal to or is less than the radius of ball  50 . If seat  32  is closer to the inside surface of the nearest side wall of tube  11  than it is to the interior surface of shank  25  then this distance is determined by a novel formulae to be equal to, or less than the radius of ball  50  so that the ball will always fall into the seat, by force of gravity, when the sampler is oriented in or near its vertical position as shown in FIG.  1  and the fluid pressure has equilibrated. 
     
       
         (d≧r) 
       
     
     Where: 
     d is the distance from the outer edge of valve means seat  32  to valve means structure interior wall  27   
     r is the radius of ball  50   
     It will be recognized by those ordinarily skilled in the art that the length and diameter of novel valve means  20  and its functional components typically are selected with consideration to the diameter of the tubing into which they are affixed which is selected with consideration to the size of the well being sampled and the volume of sample specimen required. In that regard, the length and diameter of the novel valve means  20  may be varied in geometric proportion, according to a formula well known in the art, in order to secure the required testing volume and to conform to the physical structure into which it is placed. The various other components of the invention, each of which are to be discussed and described more fully herein below, would then be sized to function effectively with the dimensions of the valve means  20  so selected. Similarly, the composition of the multipurpose groundwater sampler itself and the various components from which it is constructed may be altered to provide or enhance properties suitable and appropriate for use in groundwater sampling. 
     Top portion  70  is provided consisting of handle  71  and an opening through the center of top portion  70  to tube  11  serving as pour spout  72 . Circular opening  76  truncates the bottom of top portion  70 . At the bottom of top portion  70  is a generally cylindrical, lower extended wall portion or shank  73  suitable for adaptation to tube  11 . Bottom leading edge  74  is tapered on the exterior to facilitate insertion of lower shank  73  into tube  11 . The outside diameter of lower extended wall shank  73  is approximately the same dimension as the inside diameter of tube  11  to produce a strong interference fit between tube  11  and lower extended wall shank  73  of top portion  70 . A shoulder portion  75  is provided to offset lower shank  73  from the major diameter of top portion  70  and against which tube  11  abuts when assembled. The connection between tube  11  and lower shank  73  produces a watertight fit. O-rings, plumbing tape, or other sealant may be utilized to produce a seal as well. Top portion  70  is secured in place by heat welding at spots along the circumference where tube  11  overlaps shank  73 . Alternately clamping, screwing, riveting, sonic welding or other means of mechanical attachment can be performed. 
     FIG. 3 illustrates optional top portion  80  which can replace top portion  70  for special purposes of preventing fluids in sample chamber  11  from escaping out top portion  80  if the sampler continues to descend in the well after tube  11  is full. Optional top portion  80  consists of a handle  81  and an opening through the center of top portion  80  to tube  11  serving as a pour spout pour spout  85 . Opening  85  is circular and concentric to tube  11  and to top portion  80 . Opening  85  is approximately 0.625 inches in diameter and is beveled inward on its interior bottom surface according to a formulae known in the art of valve seals and seats, to produce a valve means seat  86  against which a spherical ball  90  or other stopper, plug, or other valve means can fit to create a one way seal which will remain in the open position until fluid rises to the top of inside of tube  11  sample chamber. Spherical ball  90  shown in the preferred embodiment of FIG. 3 is made of a suitably inert material having a specific gravity less than the fluid to be sampled such that it floats, and has a diameter sized in accordance with known principles for utilizing a ball as a valve means to plug the circular opening at top portion  80 . In the embodiment, ball  90  is 0.75-inch diameter. 
     At the bottom of top portion  80  is a generally cylindrical, lower extended wall portion or shank  83  suitable for adaptation to tube  11 . Bottom leading edge  84  is tapered on the exterior to facilitate insertion of lower shank  83  into tube  11 . The outside diameter of lower shank  83  is approximately the same dimension as the inside diameter of tube  11  to produce a strong interference fit between tube  11  and lower shank  83  of top portion  80 . A shoulder  82  offsets lower shank  83  from the major diameter of top portion  80  and against which tube  11  abuts when assembled. The connection between tube  11  and lower shank  83  produces a watertight fit. O-rings, plumbing tape, or other sealant may be utilized to produce a seal as well. Top portion  80  is secured in place by heat welding at spots along the circumference where tube  11  overlaps shank  83 . Alternately clamping, screwing, riveting, sonic welding, or other means of mechanical attachment can be performed. 
     Accordingly, in the embodiment of the of the tube  11   1 illustrated in FIG. 2, cross piece  55  is positioned above valve means  20  in tube  11  a sufficient distance so as not to interfere with the operation of valve means  20 . Cross piece  55  is generally circular in the shape of a disk with openings through the flat face that allow easy transmittal of water through tube  11  but sized to prevent ball  50  from rolling through the openings along the length of tube  11 . Cross piece  55  has a diameter consistent with the inside diameter of tube  11 , in this embodiment, 1.50 inches, and is therefore held in place by a tight friction fit between its circumference and the inside circumference of tube  11 . An optional weight means  60  may be installed inside sample chamber  11  and held in place by one or more cross pieces  55  or by a friction fit between the outside edges of the weight means  60  and the inside circumference of tube  11 . 
     Having thus described exemplary embodiments of the present invention, it should be noted by those ordinarily skilled in the art that the within disclosures are exemplary only, and that various other alternatives, adaptations, and modifications may be made within the scope of the present invention. Accordingly, the present invention is not limited to the specific embodiments as illustrated herein, but is limited only by the following claims.