Stacked dynamic steady-state flow and chemistry profiling for long-screened test wells used in mud rotary pilot holes

Abstract

A method and system for determining dynamic steady-state flow and chemistry of groundwater within a long-screened test well, includes (i) drilling a pilot hole through an aquifer; (ii) installing a test well within the pilot hole, including a well screen that is at least 40 feet in length; (iii) positioning a pump within the test well to move the groundwater within the test well; (iv) positioning a packer assembly within the test well to selectively provide a seal between the test well and the pilot hole; and (v) performing downhole testing at a plurality of different depths within the test well with miniaturized technologies that are equal to or less than 1.5 inches in diameter to determine a dynamic steady-state flow and chemistry profile of the groundwater within the test well. The pump is used at a first depth and then is moved to a second depth within the test well to perform stacked dynamic steady-state flow and chemistry profiles. The miniaturized technologies include a tracer injection system that determines downhole velocity and flow measurements of the groundwater within the test well, and a groundwater sampling system that selectively removes groundwater samples from the test well.

1 . A method for determining dynamic steady-state flow and chemistry of groundwater within a long-screened test well, the method comprising steps of:
 drilling a pilot hole through one or more aquifers;   installing a test well within the pilot hole, the test well including a well screen;   positioning a pump at a first depth within the test well;   moving the pump to a second depth within the test well that is different than the first depth;   positioning a packer assembly within the test well, the packer assembly being configured to selectively provide a seal between the test well and the pilot hole; and   performing downhole testing with the pump at each of the first depth and the second depth within the test well with miniaturized technologies that are equal to or less than 1.5 inches in diameter, the downhole testing being utilized to determine stacked dynamic steady-state flow and chemistry profiles of the groundwater within the test well.   
     
     
         2 . The method of  claim 1  wherein the step of installing includes the well screen being continuous. 
     
     
         3 . The method of  claim 1  wherein the step of installing includes the well screen being formed in a plurality of screened sections. 
     
     
         4 . The method of  claim 3  wherein the step of drilling includes the pilot hole being backfilled with one of bentonite and cement to provide desired separation between the plurality of screen sections. 
     
     
         5 . The method of  claim 1  wherein the pump and the packer assembly are conjoined together, with the packer assembly including an inflatable packer that is attached to the pump near a bottom of the pump. 
     
     
         6 . The method of  claim 1  wherein the step of performing includes the miniaturized technologies including a tracer injection system that is configured to determine downhole velocity and flow measurements of the groundwater within the test well. 
     
     
         7 . The method of  claim 6  wherein the step of performing includes the tracer injection system including a flexible tube that is filled with a tracer material, the flexible tube being configured to inject the tracer material sideways into the groundwater within the test well to determine the downhole velocity and flow measurements; wherein air bubbles are inhibited from entering the flexible tube; and wherein timing of injection of the tracer material from the flexible tube into the groundwater within the test well is controlled at least in part by a timer control unit. 
     
     
         8 . The method of  claim 6  wherein the step of performing includes the miniaturized technologies further including a groundwater sampling system that is configured to selectively remove groundwater samples from the test well. 
     
     
         9 . The method of  claim 8  wherein the step of performing includes the groundwater sampling system including a miniaturized pump, a section of jacketed tubing, and a volume booster; and wherein the section of jacketed tubing includes a first tube that is configured to deliver compressed gas from a surface level to a targeted sampling depth, and a second tube that is configured to transfer groundwater from the targeted sampling depth to the surface level. 
     
     
         10 . The method of  claim 8  wherein the tracer injection system and the groundwater sampling system are joined into a single, conjoined, downhole unit so that the tracer injection system and the groundwater sampling system move together to different depths within the test well. 
     
     
         11 . A flow and chemistry profiling system for determining dynamic steady-state flow and chemistry of groundwater within a long-screened test well, the flow and chemistry profiling system comprising:
 a pilot hole that is drilled through one or more aquifers;   a test well that is installed within the pilot hole, the test well including a well screen;   a pump that is positioned at a first depth within the test well, the pump being selectively moved to a second depth within the test well that is different than the first depth;   a packer assembly that is positioned within the test well, the packer assembly being configured to selectively provide a seal between the test well and the pilot hole; and   miniaturized technologies that are utilized for performing downhole testing at each of the first depth and the second depth within the test well, the miniaturized technologies being equal to or less than 1.5 inches in diameter, the downhole testing being utilized to determine stacked dynamic steady-state flow and chemistry profiles of the groundwater within the test well.   
     
     
         12 . The flow and chemistry profiling system of  claim 11  wherein the well screen is continuous. 
     
     
         13 . The flow and chemistry profiling system of  claim 11  wherein the well screen is formed in a plurality of screened sections. 
     
     
         14 . The flow and chemistry profiling system of  claim 13  wherein the pilot hole is backfilled with one of bentonite and cement to provide desired separation between the plurality of screen sections. 
     
     
         15 . The flow and chemistry profiling system of  claim 11  wherein the pump and the packer assembly are conjoined together, with the packer assembly including an inflatable packer that is attached to the pump near a bottom of the pump. 
     
     
         16 . The flow and chemistry profiling system of  claim 11  wherein the miniaturized technologies include a tracer injection system that is configured to determine downhole velocity and flow measurements of the groundwater within the test well. 
     
     
         17 . The flow and chemistry profiling system of  claim 16  wherein the tracer injection system includes a flexible tube that is filled with a tracer material, the flexible tube being configured to inject the tracer material sideways into the groundwater within the test well to determine the downhole velocity and flow measurements; wherein air bubbles are inhibited from entering the flexible tube; and wherein timing of injection of the tracer material from the flexible tube into the groundwater within the test well is controlled at least in part by a timer control unit. 
     
     
         18 . The flow and chemistry profiling system of  claim 16  wherein the miniaturized technologies further include a groundwater sampling system that is configured to selectively remove groundwater samples from the test well. 
     
     
         19 . The flow and chemistry profiling system of  claim 18  wherein the groundwater sampling system includes a miniaturized pump, a section of jacketed tubing, and a volume booster; and wherein the section of jacketed tubing includes a first tube that is configured to deliver compressed gas from a surface level to a targeted sampling depth, and a second tube that is configured to transfer groundwater from the targeted sampling depth to the surface level. 
     
     
         20 . The flow and chemistry profiling system of  claim 18  wherein the tracer injection system and the groundwater sampling system are joined into a single, conjoined, downhole unit so that the tracer injection system and the groundwater sampling system move together to different depths within the test well.