Abstract:
Apparatus and process for sealing of abandoned water well bores includes a hopper for dispensing comminuted well bore packing material such as a bentonite clay onto an inclined screening surface which removes undesired fine materials. A chute for collecting material flowing off of the screening surface and directing the same into the well bore is generally funnel shaped. The apparatus includes an eccentric vibrating mechanism for vibrating the inclined screening surface to remove the undesired fine materials.

Description:
This invention relates to apparatus and processes for permanently sealing abandoned well bores. More particularly, the invention relates to such apparatus and procedures used to seal abandoned water wells. 
     BACKGROUND OF THE INVENTION 
     Refilling or sealing up of abandoned water well bores is generally mandated by governmental statutes and regulations. Usually the various state Departments of Natural Resources also regulate and specify the types of material which must be introduced into the abandoned well in order to properly seal the same as well as procedures which are acceptable for such purposes. Such sealing of well bores is necessary in order to prevent surface water from entering underground aquifers from which drinking water is drawn and also due to safety concerns. 
     The typical regulations involved require that a material, usually a clay such as bentonite, be used to reseal the well bores. However, such materials generally must be first screened in order to avoid introduction into the aquifer of very fine materials which could interrupt or contaminate underground waterflow channels. 
     No suitable apparatus has been available, commercially, to fill the need for such apparatus. The procedures utilized heretofore have been painstaking, involving tedious manual operations using various hand tools. Thus, a substantial need has existed for improved procedures and apparatus which would facilitate sealing of abandoned well bores. 
     SUMMARY OF THE INVENTION 
     An important object of the invention is to provide improved apparatus for efficiently sealing abandoned well bores, especially those resulting from abandonment of water wells. A related object is to provide improved procedures, utilizing the apparatus, for sealing of such unused or abandoned well bores. As used herein, “well bore”, is intended to include the open shaft of a well whether or not a casing is contained therein. 
     In accordance with one aspect of the invention, the process involves the introduction of comminuted bentonite into a hopper out of which the flow of material is regulated by means of a suitable flow control mechanism. In accordance with another related aspect, the material flows from the hopper down an inclined screening surface which removes undesired fine materials prior to feeding the mixture, such as bentonite, into the well bore. 
     In accordance with a further aspect of the invention, a vibrating mechanism, usually employing an eccentric vibration causing means, is used to vibrate the inclined screen in order to efficiently cause separation of the fine materials from the blend which is used. Another advantage of the invention is that the vibrating mechanism also helps to efficiently cause flow of the materials out of the hopper onto the screening surface. 
     In accordance with still a further aspect of the invention, a collecting and distributing chute is provided at the bottom of the inclined screening surface to collect, and divert into the well bore, the screened clay materials which are used to reseal the well bore, and to efficiently direct the same into the well bore. 
     In accordance with further aspects of the invention, the apparatus is compact and transportable. The apparatus includes adjustable and collapsible supporting legs which can be folded against the main body of the apparatus for easy transportation thereof. 
     Further objects and advantages of the invention will be apparent from the following claims and detailed description of the preferred embodiment, and by the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevational view of the preferred apparatus of the invention; and, 
     FIG. 2 is a perspective view of the apparatus shown in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The apparatus of this invention is generally indicated by numeral  10 . As seen, the apparatus includes flow directing apparatus in the form of a generally funnel shaped collecting/flow directing receptacle  11 . The collecting portion of the funnel-shaped flow director  11 , as best seen in FIG. 2, is preferably of a rectangular configuration, and narrows to a lower portion  12  adapted to direct the flow of particles of a well bore resealing material, such as bentonite  14 . As seen, the bentonite is directed, as indicated by arrows, into the well bore  16 . 
     Also, referring to the drawings, it is seen that the main body of the apparatus  10  is supported by a pair of side frame beams  18  connected by a plurality of supporting cross-members  19 . As shown, the side beams or rails  18  are formed of a C-shaped configuration, but it should be understood that other configurations may be substituted. Also, while the funnel-shaped flow director  11 ,  12  is shown to be rectangular in configuration, it will be apparent to those skilled in the art that these components can be of other configurations, for example, circular. 
     The side frame members  18  are supported by adjustable front legs  20  and rear legs  22 , which are pivotally connected to side frame members  18  and which are preferably formed of a telescoping configuration so that the length thereof can be adjusted to adapt to various slopes and irregularities of the terrain surrounding the well. 
     As best seen in FIG. 1, each of the legs  22  has a telescoping end  23  and the legs  20  have telescoping end sections  21  suitable for the purpose adjusting the apparatus  10  to the slope of the terrain on which it is used. 
     Each of the legs  20  and  22  is connected by a bolt  25 , or similar fastener, to the side frame member  18 , so that it is pivotable thereagainst. Thus, the legs  20  and  22  can each be folded toward each other for transportation and extended downwardly, as illustrated, for use. Preferably, each of the legs is provided with a cord or cable  24  which limits the pivoting of the legs  20  and  22 , thereby stabilizing the structure of apparatus  10  during use. 
     Also as seen in the drawings, the apparatus  10  is provided with a material-feeding hopper  30  supported on the side rails  18  by suitable brackets  31 . Hopper  30  into which the bentonite  14  or similar material is fed is of a size convenient to receive batches of the bentonite as required for filling the well bore  16 . 
     At the bottom of the hopper  30 , there is provided a slidable plate  36 , which can be extended or retracted in order to control the size of the opening between the hoppers  30  and a screen  40  supported by side rails  18  and cross members  19  so that the rate of flow of the bentonite material  14  can be controlled, or discontinued entirely, when required. 
     Placed along the length of the space between side rails  18  is a screen  40 . Screen  40  has openings of a size such as required to remove the fines  48  from the bentonite material  14 . Generally these openings may be about ¼ inch, which has been found to comply with the most stringent code requirements which generally require a 3 minute screening period for a 50 lb. batch of bentonite. Usually, the fines are simply allowed to fall on and become blended into the surface soil adjacent to the well bore  16 . However, if desired, the fines could be removed by collection thereof on a canvass or other collecting surface. 
     In order to ensure efficient separation through screen  40  of fines  48  and directing of the remainder of the bentonite  14  into the collecting funnel structure  11 , there is provided a vibrating device  42 . Vibrator  42  is preferably based on the use of a rotatable mechanism which is eccentric which thus causes vibration during rotation thereof together with the entire structure of device  10 . Vibrator  42  is supported on a crossbar  44 , which is, in turn, supported on two cross rails  18  by means of suitable mounting brackets  46 . 
     In practice, the legs  20  and  22  are folded against the frame  18 , and held in place either by Velcro® straps  27  or rubber cords, commonly referred to as “bungee cords”, or other fastening means. Then, the apparatus  10  is erected over the abandoned well bore  16  as indicated. The side frame rails  18  are placed at a downwardly extending angle toward the chute  11  due to the differing lengths of the shorter forward legs  20  and the longer rear legs  22 . These legs are adjusted to account for irregularities in the terrain surrounding the well bore  16 . After the apparatus has thus been set-up in place, a suitable amount of bentonite  14  is placed in the upper hopper  32  and the vibrator motor  42  started. Generally, such a motor may be either gasoline powered or electrically powered, using a portable generator or power source available at the site. Then, the sliding flow control plate  36  is opened to commence the flow of the bentonite onto the inclined screening surface  40 . The bentonite  14 , with the fines  48  removed, continues its flow into the collecting chute  11 , and are dropped into the well shaft  16 . The procedure is continued until the well shaft is suitably packed with the bentonite. It will be apparent that, reversing the set-up steps after completion of the well sealing procedure, the apparatus  10  is readily retracted into a transport position for removal, either to storage, or another job site. 
     While preferred embodiments of the invention have been shown and described for purposes of illustration, it will be apparent to those skilled in the art that various other modifications may be made without departing from the spirit of the invention.