Abstract: A well installation preform for locating and dispensing granular materials nto a bore hole around the screen of a well casing is disclosed. A cylindrical sleeve containing a liner is assembled about the screen end of the well casing. The space between the sleeve and the well casing is filled with an ordered layer of granular material including a filter material adjacent the screen, a sealing material above the filter material and the screen and a quantity of filler material above the sealing material. The lower end of the sleeve is blocked while the preform is lowered into the well. The sleeve is thereafter removed whereby the liner is everted and the granular material is uniformly dispensed about the well casing in the bore hole. The sealing material forms a seal above the filter material for establishing an isolated filtration zone about the screen. A method of constructing the well using the preform and the resulting well structure is also disclosed.

Abstract: A method for digitally constructing variable width cartographic lines, the invention provides an algorithm for generating symbolized lines using multiply-stroked centerline data. The algorithm allows generation of software which utilizes trigonometric functions and which can be implemented in applications using vector data with vector or raster plotters. The algorithm further accounts for basic cartographic principles, existing algorithm characteristics and hardware constraints imposed by specific output devices.

Abstract: A method and apparatus for directly measuring the hydraulic conductivity of porous materials at various degrees of saturation, the invention involves determination of the rate of rotation under dynamic equilibrium of concentric cylinders having a partially saturated porous material disposed in an annular space between the concentric cylinders, the rate of rotation being directly related to the hydraulic conductivity of the material. The hydraulic conductivity of the material can thus be determined without the need for measuring fluid discharge and piezometric head gradient as is necessary in prior art determination of hydraulic conductivity.