Atlantic Richfield Company

Paul A Fletcher

Carl T Montgomery

Gangerico G Ramos

Gregory S Walz

Brian E Shannon

A method for reducing the concentration of radioactive material in a contaminated area by removing contaminated soil from the contaminated area; determining a field survey specific activity concentration representative of the remaining soil in the contaminated area; comparing the field survey specific activity concentration with a field validation data set to determine the total concentration of contaminating radioactive material in the contaminated area and removing additional quantities of contaminated soil from the contaminated area as required. The soil area may alternatively be blended with clean soil to reduce the concentration of radioactive material in the soil or a combination of blending and removal may be used. A method for estimating the total concentration of radioactive material in a soil sample is provided.

Method for reducing the concentration of contaminating radioactive

Remotely controllable fluid flow control valves are disposed in the main wellbore and branch wellbores of a multiple well. Each flow control valve has a radio frequency range receiver, a controller and an actuator for moving a closure member to a selected position to control fluid flow in the wellbore in which the valve is disposed. A signal transmitter may be conveyed into the main wellbore by an E-line or coilable tubing and radio frequency range electromagnetic wave energy signals may be transmitted to the selected valve to effect fluid flow control within each wellbore of the multiple well. The remotely controllable valves eliminate expensive and difficult procedures associated with reentering branch wells extending from a central or main wellbore.

Downhole flow control in multiple wells

Pressure and temperature signals are transmitted between a predetermined point in a wellbore and the earth's surface by an electromagnetic wave transmitter disposed in the well and connected to a bow-spring centralizer forming one contactor of a dipole and a mandrel or hanger connected to a landing nipple of a tubing string in the well whereby the other conductive path forming the other end of the dipole may be formed by a packer or similar mechanism in conductive engagement with the tubing string and the well casing. The hanger may be a lock mandrel or a suitable conventional downhole tool hanger. The electromagnetic wave transmitter may be deployed in the well and engaged with the casing by spaced-apart magnets to establish the conductive path and the dipole distance. The transmitter may also be deployed on and connected to coilable tubing which has an insulative coating on the exterior surface for a predetermined length to prevent short-circuiting the conductive path by engagement of the coilable tubing with the casing wall, for example.

Downhole instruments for well operations

A method for determining the minimum length for a fracture in a fluid-producing formation to control the production of sand therefrom wherein a plurality of critical drawdown pressures are calculated from known formation data which correspond to a plurality of different, estimated respective fracture lengths. Once the critical drawdown pressures for the reservoir are correlated with their corresponding fracture lengths, a critical drawdown curve for that particular reservoir is established. Additional sets of curves are generated from known data which when overlaid with the critical drawdown pressure curve allows a minimum length of fracture to be selected which will produce the formation at a given rate at a prescribed drawdown pressure without producing any substantial amounts of sand from the formation.

Method for fracturing a formation to control sand production

Toxic wastes including naturally occurring radioactive materials are disposed of into subterranean earth formation zones which are bounded both above and below by zones which have higher in situ compressive stresses. The materials are prepared in a slurry of finely ground solids and a carrier liquid and are injected into a fracture created in the disposal zone by a process which includes initiating and extending the fracture with a fracturing fluid having a filter cake building solids material entrained therein to build a sealant layer on the fracture faces, The fracture fluid is followed by injection of the waste material which is followed by injection of more fracture fluid and/or a clear liquid such as fresh water or seawater to remove all toxic material from the injection well and the vicinity thereof. The fracture is then allowed to close to confine the waste material therein.

Subterranean disposal of wastes

Injection well fluid flow is measured by a device which has a running head and a body with a turbine type flowmeter interposed therein between the running head and discharge port means in the body. The running head may be interchangeable for positioning the body in selected positions in a tubing string in sealing engagement with a seating surface in the tubing string whereby fluid flow entering selected zones in communication with the injection well may be directly measured. The flow measuring device may include a signal storage or memory circuit disposed thereon for receiving and storing signals from the flowmeter.

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Richardson, TX, United States of America

Paul A Fletcher