- Email: [email protected]
Effect of leachate mounding and sand lenses on contaminant migration from a landfill cell
PROPERTIES:DEFORMATION & STRENGTH
Chemical and physical changes due to water
951045 Classification and determination of the set of properties of cohesive soils (with software) S. S. Sawateev, Soil Mechanics & Foundation Engineering, 31(1), 1994, p 7; translated from: Osnovaniya, Fundamenty i Mekhanika Gruntov no. 1, 1994, p 6.
7A
Measurement of water pressure and its effects 951048 Numerical modelling of abnormal fluid pressures in the Navarin Basin, Bering Sea O. Bour & I. Lerche, Marine & Petroleum Geology, 11(4), 1994, pp 491-500.
A new method is proposed for the classification and determination of indicators of the basic properties of cohesive soils as a function of the speed at which they are softened by water. Experimental determination of the speed at which a soil is softened by water is one of the simplest the least time-consuming methods in hydraulic engineering. Its well-defined quantitative expression is proposed, and the order of its determination is established. Qualitative relationships for determination of basic soil propertiees from the speed of softening by water and porosity are investigated and established. The method is implemented by a program stored on a magnetic medium for a personal computer. Inputting the speed of softening and porosity, it is possible to obtain the name of the soil and the complete set of its characteristics. The development engineers have found methodological and technological uses. (Journal summary)
The Navarin Basin, located in the Bering Sea, Alaska, is composed of three major units: 1) a thick Late Eocene and Oligocene overpressured shaly section; 2) a Miocene sandy section; and 3) a Late Miocene to Pliocene section, characterized by high porosity and a possible zone of abnormal pressure due to the presence of diatomaceous shales. To model the fluid flow and compaetional history of the basin, a cross-section was used, controlled by four wells for which porosity and pressure data were available. A twodimensional model was constructed which reproduced correctly the variation of porosity and pressure data with depth for the four wells. The main overpressure in the deeper part of the basin arose during the earliest stages of basin filling by shale because of strong undercompaetion. In the shallower part of the basin, high porosity values were obtained in agreement with the data, whereas some overpressure was developed in association with the undercompaetion and low permeability of the diatomaceous shales. (from Authors)
951046 Effect of leachnte mounding and sand lenses on contaminant migration from n landfill cell R. K. Rowe & K. W. E. San, Computers & Geotechnics, 16(3), 1994, pp 173-204.
951049 An efficient algorithm for computation of well responses in commingled reservoirs J. B. Spath, E. Ozkan & R. Raghaven, SPE Formation Evaluation, 9(2), 1994, pp 115-121.
The effect of leachate mounding between drains at the edge of a landfill cell upon the flow field and contaminant migration to an underlying aquifer is examined. It is demonstrated that the impact is controlled by the downward component of the velocity and that once contaminant reaches an aquifer very little will return to the collection drains even if there is upward flow from the aquifer to these drains. It is shown that the simplified procedure of using the average velocity beneath a landfill in simple contaminant transport analyses is not valid when there is a significant component of the flow which is upward to the drains. The effect of the presence of up to 15°/, sand lenses in the aquitard is also examined. It is found that the sand lenses have relatively little effect on the impact in an underlying aquifer for the range of cases considered. (from Authors)
An algorithm to compute pressure distributions in commingled reservoirs that are produced by complex, completion systems is described. Single-layer solutions for systems of interest can be readily combined to obtain pressure distributions in commingled reservoirs for combinations of rock types. Completion schemes and outer-boundary conditions for each layer may be different. Theoretical claims are substantiated by considering example applications. (Authors)
951047 Fundamentals of shale stabilization: water transport through shales T. J. Ballard, S. P. Beare & T. A. Lawless, SPE Formation Evaluation, 9(2), 1994, pp 129-134. An experimental technique has been developed that uses radioactive tracers to monitor the progress of water and selected dissolved ions through a shale core plug. By varying experimental parameters the dominant mechanisms by which water is transported through shales have been identified. Under conditions of zero applied pressure, diffusion processes control water and ion movement through shales. Concentration gradients are the driving force for mass transfer of ionic species through shales. There is no evidence to indicate that osmosis caused mass transfer of water. Applied pressure caused an increase in water and ion transport rates. Above a threshold pressure, water and dissolved ions travel at the same rate irrespective of the ion concentration. (from Authors)
951050 Pressure-transient model for a vertically fractured well in a fractal reservoir R. A. Beier, SPE Formation Evaluation, 9(2), 1994, pp 122128. In many cases, field pressure-transient data are matched with a homogeneous reservoir model to obtain effective reservoir properties for a heterogeneous reservoir. This paper presents field data and a model that demonstrate that this approach does not always work. As an alternative, a model is developed for a well with a vertical fracture in a reservoir with a fractal structure. (Author)
PROPERTIES OF ROCK & SOILS Deformation and strength characteristics 951051 Strength of cemented grains Hezhu Yin & J. Dvorkin, Geophysical Research Letters, 21(10), 1994, pp 903-906.
Chemical and physical changes due to water
951045 Classification and determination of the set of properties of cohesive soils (with software) S. S. Sawateev, Soil Mechanics & Foundation Engineering, 31(1), 1994, p 7; translated from: Osnovaniya, Fundamenty i Mekhanika Gruntov no. 1, 1994, p 6.
7A
Measurement of water pressure and its effects 951048 Numerical modelling of abnormal fluid pressures in the Navarin Basin, Bering Sea O. Bour & I. Lerche, Marine & Petroleum Geology, 11(4), 1994, pp 491-500.
A new method is proposed for the classification and determination of indicators of the basic properties of cohesive soils as a function of the speed at which they are softened by water. Experimental determination of the speed at which a soil is softened by water is one of the simplest the least time-consuming methods in hydraulic engineering. Its well-defined quantitative expression is proposed, and the order of its determination is established. Qualitative relationships for determination of basic soil propertiees from the speed of softening by water and porosity are investigated and established. The method is implemented by a program stored on a magnetic medium for a personal computer. Inputting the speed of softening and porosity, it is possible to obtain the name of the soil and the complete set of its characteristics. The development engineers have found methodological and technological uses. (Journal summary)
The Navarin Basin, located in the Bering Sea, Alaska, is composed of three major units: 1) a thick Late Eocene and Oligocene overpressured shaly section; 2) a Miocene sandy section; and 3) a Late Miocene to Pliocene section, characterized by high porosity and a possible zone of abnormal pressure due to the presence of diatomaceous shales. To model the fluid flow and compaetional history of the basin, a cross-section was used, controlled by four wells for which porosity and pressure data were available. A twodimensional model was constructed which reproduced correctly the variation of porosity and pressure data with depth for the four wells. The main overpressure in the deeper part of the basin arose during the earliest stages of basin filling by shale because of strong undercompaetion. In the shallower part of the basin, high porosity values were obtained in agreement with the data, whereas some overpressure was developed in association with the undercompaetion and low permeability of the diatomaceous shales. (from Authors)
951046 Effect of leachnte mounding and sand lenses on contaminant migration from n landfill cell R. K. Rowe & K. W. E. San, Computers & Geotechnics, 16(3), 1994, pp 173-204.
951049 An efficient algorithm for computation of well responses in commingled reservoirs J. B. Spath, E. Ozkan & R. Raghaven, SPE Formation Evaluation, 9(2), 1994, pp 115-121.
The effect of leachate mounding between drains at the edge of a landfill cell upon the flow field and contaminant migration to an underlying aquifer is examined. It is demonstrated that the impact is controlled by the downward component of the velocity and that once contaminant reaches an aquifer very little will return to the collection drains even if there is upward flow from the aquifer to these drains. It is shown that the simplified procedure of using the average velocity beneath a landfill in simple contaminant transport analyses is not valid when there is a significant component of the flow which is upward to the drains. The effect of the presence of up to 15°/, sand lenses in the aquitard is also examined. It is found that the sand lenses have relatively little effect on the impact in an underlying aquifer for the range of cases considered. (from Authors)
An algorithm to compute pressure distributions in commingled reservoirs that are produced by complex, completion systems is described. Single-layer solutions for systems of interest can be readily combined to obtain pressure distributions in commingled reservoirs for combinations of rock types. Completion schemes and outer-boundary conditions for each layer may be different. Theoretical claims are substantiated by considering example applications. (Authors)
951047 Fundamentals of shale stabilization: water transport through shales T. J. Ballard, S. P. Beare & T. A. Lawless, SPE Formation Evaluation, 9(2), 1994, pp 129-134. An experimental technique has been developed that uses radioactive tracers to monitor the progress of water and selected dissolved ions through a shale core plug. By varying experimental parameters the dominant mechanisms by which water is transported through shales have been identified. Under conditions of zero applied pressure, diffusion processes control water and ion movement through shales. Concentration gradients are the driving force for mass transfer of ionic species through shales. There is no evidence to indicate that osmosis caused mass transfer of water. Applied pressure caused an increase in water and ion transport rates. Above a threshold pressure, water and dissolved ions travel at the same rate irrespective of the ion concentration. (from Authors)
951050 Pressure-transient model for a vertically fractured well in a fractal reservoir R. A. Beier, SPE Formation Evaluation, 9(2), 1994, pp 122128. In many cases, field pressure-transient data are matched with a homogeneous reservoir model to obtain effective reservoir properties for a heterogeneous reservoir. This paper presents field data and a model that demonstrate that this approach does not always work. As an alternative, a model is developed for a well with a vertical fracture in a reservoir with a fractal structure. (Author)
PROPERTIES OF ROCK & SOILS Deformation and strength characteristics 951051 Strength of cemented grains Hezhu Yin & J. Dvorkin, Geophysical Research Letters, 21(10), 1994, pp 903-906.