Groundwater flow drainage

Fig. 8-7 Three principal ratios control the style of runoff generation prevalent in a landscape (1) ratio of rainfall intensity to the infiltration capacity of the soil (2) ratio of bedrock conductivity to soil conductivity and (3) the topographic index defined by the ratio of the upslope drainage area to the ground slope. HOF = Horton overland flow SOF = saturation overland flow SSS = subsurface stormflow GWR = groundwater flow.

A closer look at the zone of lateral base flow (overflow). Overflowing water flows laterally by the critical angle. This angle is determined by the water viscosity, which in turn is dependent on the temperature and concentration of dissolved ions. Groundwater flows laterally toward the terminal base of drainage at a critical angle that is determined by the hydraulic conductivity, or permeability, of the rocks (k) the water viscosity, which depends on the temperature (7), and the concentration of dissolved ions (i) ... 

Toth, J. (1963) A theoretical analysis of groundwater flow in small drainage basins. J. Geophys. Res. 68, 4795 4812. 

Characterization of the natural setting is usually a major portion of the field investigation. At most sites, permeability of the local soil and rock types, the depth of the water table, and the direction of groundwater flow will strongly influence movement of contaminants from the point of disposal. The anomalies which occur naturally within the geohydrologic section must be taken into consideration. Surface drainage, sewers, and buried utilities can affect surface and groundwater flow around a hazardous waste site. 

T6th describes the gravity-induced groundwater flow pattern in terms of interdependent flow systems as existing in drainage basins. A drainage basin is a depression of the ground surface, partly or entirely surrounded by... 

Figure 2.20 Cross-section showing the theoretical distribution of hydraulic head and gravity-induced groundwater flow pattern in a homogeneous and isotropic drainage basin with complex ground surface geometry (modified after T6th, 1970. Reprinted by permission of the National Research Council of Canada).

Figure 2.21 Lateral groundwater flow patterns for isotropic drainage basins with simple ground surface geometry (ground surface geometry types patterned after basin geometry types given by Pratsch, 1982).

Figure 2.24 Cross-sections showing the theoretical effect of a partial aquifer of relatively good permeability on the distribution of hydraulic head and gravity-induced groundwater flow pattern in two drainage basins (after Freeze and Witherspoon, 1967, Water Resources Research, Vol. 3, no. 2, Fig. 4, p. 629. Copyright by the American Geophysical Union).

Figure 5.13 Cross-section of a horizontally layered drainage basin showing positions of hydraulic traps in connection with the gravity-induced groundwater flow systems (modified after Tdth, 1980. Reprinted by permission of the American Association of Petroleum Geologists).

Freeze, R.A., 1969. Regional groundwater flow — Old Wives Lake drainage basin, Saskatchewan. Can. Dep. Energy, Mines Resour., Inland Waters Branch, Sci. Ser. No. 5, 245 pp. 

The Pinal Creek basin in central Arizona, about 100 km east of Phoenix, is one of the most polluted acid mine drainage sites in the USA (Figure 9.2). Mining activities over a century, mostly in copper from porphyry deposits, have resulted in a plume of acidic groundwater in the alluvium and basin fill aquifer. The plume is laden with heavy metals. Many potential contamination sources, including mine tailings, heap leach, surface impoundments, and surface run-off and groundwater flow in the mineralized... 

Migration Pathways Groundwater flow patterns, buried utilities, drainage improvements, exposed affected surface soils. Identify based on site characterization andfate-and-transport data (see below). 

The permeability or hydraulic conductivity of the fill must be large enough not only to allow for percolation of water through the unsaturated zone, but also to ensure sufficient groundwater flow (internal drainage) to prevent the water from rising to an unacceptable level. 

FIGURE 6 Meteoric waters and creek runoff for White Rock Creek, a small drainage in Dallas County, TX. Note that the creek waters also lie close to meteoric water line and exhibit less variation. Shallow groundwater flow into the creek delivers a smoothed weighted average precipitation composition slightly modified by evaporation. Each local area has its own meteoric water line. 

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