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Water tracers and investigatory techniques
159A
88,1031 Groundwater models Rushton, K R In: Groundwater: occurrence, development and protection, edited by T W Brundon (Water Practice Manuals: 5) P189228. Publ London: Institution of Water Engineers and Scientists, 1986
884O35 Determination of aquifer parameters at a ground-water recharge site Urban, J B; Gburek, W J Ground Water V26. NI. Jan-Feb 1988. P39-53
Groundwater models are used to help understand, interpret and predict flow in aquifers, and aim to represent all the different features of groundwater flow. The various steps in model formulation, including governing equations and external boundaries, are discussed. The use of the finite difference method to represent aquifer problems is explained, and numerical examples given to illustrate the models. Horizontal and vertical components of flow, prediction, radial flow models and modelling quality changes are also discussed.
Porous asphalt pavement is a stormwater management technique to reduce runoff and enhance groundwater recharge. Accurate characterization of aquifer properties at recharge sites is important in design. Various experimental techniques were used to examine hydraulic conductivity (k) and specific yield (Sy) to assess their accuracy of representation of aquifer hydraulic properties. They yielded comparable values, but the fractured aquifer exhibits hydraulic properties significantly different from those of the rock matrix, therefore field-based techniques which match the time and space scale in which the facility is expected to affect the aquifer should be used to obtain k and Sy.
884O32 Water tracers and investigatory techniques White, K E In: Groundwater: occurrence, development and protection, edited by T W Brandon ( Water Practice Manuals: 5) P353383. Publ London: Institution of Water Engineers and Scientists. 1986
884O36 Application of vertical drainage to dewatering seacoasts AI Roomi al Nashie, K Int Assoc Engng G¢oi Bull N36. Oct 1987. P3-9
Information on groundwater movements may be obtained by detecting tracers already in the environment, or by the injection of selected tracer substances. Techniques to detect the naturally occurring tracers, radionuclides from bomb-testing, natural radionuclides and stable isotopes, are presented. The selection, application method, usefulness and safety aspects of various chemical, dye, radioactive and biological tracers are discussed. Case studies are presented to illustrate tracer selection procedures for a variety of situations, eg fluorescent dyes in a lake with nearby sewage works, shortlived radiotracer in a landfill pollution problem. 884033 Design of boreholes and wells Wilkinson, W B In: Groundwater: occurrence, development and protection, edited by T W Brandon ( Water Practice Manuals: 5) P385406, Publ London: Institution of Water Engineers and Scientists. 1986 The design of a borehole or well is dependent upon its proposed use, quantity or quality of water or waste to be withdrawn or recharged, hydrogeology of the aquifer and economic factors. The design of screens and casings, to allow groundwater to flow into the well with minimum hydraulic losses, but prevent the entry of sand and give the walls structural stability, is discussed, along with composition of the associated filter pack. Casing materials and pumping methods are described.
884034 Solute transport during unsteady, unsaturated soil water flow: the pulse input Bond. W J Aust J Soil Res 1/25. N3. 1987. P223-231 A general approximate analytical solution for the movement and dispersion of a solute pulse during unsteady groundwater flow in unsaturated soils is presented. Pulses arising from nonuniform original distribution of solute in the soil or from changes in groundwater chemistry are considered. Experimental studies used tritiated water and chloride ion pulses in constant flux infiltration of a clay soil. Agreement with the equation was good for tritium but much poorer for chloride. The shape of solute pulses was also studied.
The design of a vertical drainage system to lower the water table at Habbaniya, Iraq, is presented. Pumping tests were undertaken to determine aquifer properties and the feasibility of installing tube wells. The quantity of groundwater inflow and outflow is calculated using a flow net,and two alternative tube well designs are presented. 884037 Estimates of specific yield with the geoelectric resistivity method in glacial aquifers Frohlich, R K: Kelly, W E J Hydeol 1/97. NI/2. 15 Jan 1988. P33-44 Low cost geoelectrical depth sounding after Schlumberger is examined as a method of determining specific yield without direct access to an aquifer. The method is based on a determination of the layer resistivity for the saturated and unsaturated zones and the water resistivity. Porosity and degree of saturation are estimated using Archie's law. Specific yield estimated in this way agrees with estimates based on porosity and median grain size (Preuss and Todd, 1963). Errors associated with the analysis are considered. 884038 Statistical possibilities for predicting hydraulic properties from geoelectrical parameters in a strongly heterogeneous aquifer (In French) Razack, M; Sinan, M g Hydvol i,'97. N3/4, 15 Feb 1988, P323-340 Attempts are made to correlate values of hydraulic transmissivity (T) and transverse resistance (TR) for a strongly heterogeneous alluvial aquifer. Linear, exponential and geometrical statistical regression are examined. The best results are obtained using geometrical regression of T on TR of only the permeable beds. When results are corrected to the same watertable elevation, prediction of T is significantly improved, A relation is proposed to predict transmissivity at low cost and with reasonable accuracy.
Chemical and physical changes due to See: 884015
1988 Pergamon Press pie. Reproduction not permitted RMM$
25~-F
water
88,1031 Groundwater models Rushton, K R In: Groundwater: occurrence, development and protection, edited by T W Brundon (Water Practice Manuals: 5) P189228. Publ London: Institution of Water Engineers and Scientists, 1986
884O35 Determination of aquifer parameters at a ground-water recharge site Urban, J B; Gburek, W J Ground Water V26. NI. Jan-Feb 1988. P39-53
Groundwater models are used to help understand, interpret and predict flow in aquifers, and aim to represent all the different features of groundwater flow. The various steps in model formulation, including governing equations and external boundaries, are discussed. The use of the finite difference method to represent aquifer problems is explained, and numerical examples given to illustrate the models. Horizontal and vertical components of flow, prediction, radial flow models and modelling quality changes are also discussed.
Porous asphalt pavement is a stormwater management technique to reduce runoff and enhance groundwater recharge. Accurate characterization of aquifer properties at recharge sites is important in design. Various experimental techniques were used to examine hydraulic conductivity (k) and specific yield (Sy) to assess their accuracy of representation of aquifer hydraulic properties. They yielded comparable values, but the fractured aquifer exhibits hydraulic properties significantly different from those of the rock matrix, therefore field-based techniques which match the time and space scale in which the facility is expected to affect the aquifer should be used to obtain k and Sy.
884O32 Water tracers and investigatory techniques White, K E In: Groundwater: occurrence, development and protection, edited by T W Brandon ( Water Practice Manuals: 5) P353383. Publ London: Institution of Water Engineers and Scientists. 1986
884O36 Application of vertical drainage to dewatering seacoasts AI Roomi al Nashie, K Int Assoc Engng G¢oi Bull N36. Oct 1987. P3-9
Information on groundwater movements may be obtained by detecting tracers already in the environment, or by the injection of selected tracer substances. Techniques to detect the naturally occurring tracers, radionuclides from bomb-testing, natural radionuclides and stable isotopes, are presented. The selection, application method, usefulness and safety aspects of various chemical, dye, radioactive and biological tracers are discussed. Case studies are presented to illustrate tracer selection procedures for a variety of situations, eg fluorescent dyes in a lake with nearby sewage works, shortlived radiotracer in a landfill pollution problem. 884033 Design of boreholes and wells Wilkinson, W B In: Groundwater: occurrence, development and protection, edited by T W Brandon ( Water Practice Manuals: 5) P385406, Publ London: Institution of Water Engineers and Scientists. 1986 The design of a borehole or well is dependent upon its proposed use, quantity or quality of water or waste to be withdrawn or recharged, hydrogeology of the aquifer and economic factors. The design of screens and casings, to allow groundwater to flow into the well with minimum hydraulic losses, but prevent the entry of sand and give the walls structural stability, is discussed, along with composition of the associated filter pack. Casing materials and pumping methods are described.
884034 Solute transport during unsteady, unsaturated soil water flow: the pulse input Bond. W J Aust J Soil Res 1/25. N3. 1987. P223-231 A general approximate analytical solution for the movement and dispersion of a solute pulse during unsteady groundwater flow in unsaturated soils is presented. Pulses arising from nonuniform original distribution of solute in the soil or from changes in groundwater chemistry are considered. Experimental studies used tritiated water and chloride ion pulses in constant flux infiltration of a clay soil. Agreement with the equation was good for tritium but much poorer for chloride. The shape of solute pulses was also studied.
The design of a vertical drainage system to lower the water table at Habbaniya, Iraq, is presented. Pumping tests were undertaken to determine aquifer properties and the feasibility of installing tube wells. The quantity of groundwater inflow and outflow is calculated using a flow net,and two alternative tube well designs are presented. 884037 Estimates of specific yield with the geoelectric resistivity method in glacial aquifers Frohlich, R K: Kelly, W E J Hydeol 1/97. NI/2. 15 Jan 1988. P33-44 Low cost geoelectrical depth sounding after Schlumberger is examined as a method of determining specific yield without direct access to an aquifer. The method is based on a determination of the layer resistivity for the saturated and unsaturated zones and the water resistivity. Porosity and degree of saturation are estimated using Archie's law. Specific yield estimated in this way agrees with estimates based on porosity and median grain size (Preuss and Todd, 1963). Errors associated with the analysis are considered. 884038 Statistical possibilities for predicting hydraulic properties from geoelectrical parameters in a strongly heterogeneous aquifer (In French) Razack, M; Sinan, M g Hydvol i,'97. N3/4, 15 Feb 1988, P323-340 Attempts are made to correlate values of hydraulic transmissivity (T) and transverse resistance (TR) for a strongly heterogeneous alluvial aquifer. Linear, exponential and geometrical statistical regression are examined. The best results are obtained using geometrical regression of T on TR of only the permeable beds. When results are corrected to the same watertable elevation, prediction of T is significantly improved, A relation is proposed to predict transmissivity at low cost and with reasonable accuracy.
Chemical and physical changes due to See: 884015
1988 Pergamon Press pie. Reproduction not permitted RMM$
25~-F
water