Aquifers mapping

A water table piezometric surface contour map is presented in Figure 12.18. The elevation of this surface varies from 10 to 40 ft below sea level across the facility. Groundwater occurring under water table conditions is first encountered between 30 and 60 ft in depth. The regional direction of flow of shallow groundwater is toward a depression in the piezometric surface of the Gage aquifer located about... 

Composition of Water in Adjacent Wells as a Tool for Spatial Mapping of Stagnant Aquifers... 

Fig. 4.20 Monthly maps of equal groundwater temperature for a well field bordering the Mohawk River (after Winslow et al., 1965). The river temperature changed over an annual cycle from 77 to 32 °F. The aquifer followed these temperature changes, indicating recharge from the river.

Fig. 4.22 Location map of wells near the Mohawk River with annual groundwater temperatures (from Winslow et al., 1965). Using these values, contours of equal annual temperature variation were drawn. The decrease of these contour values indicates water moves from the river into the aquifer, especially through the zone marked A.

Fig. 10.11 Isotritium lines (inTU) for wells in a shallow aquifer on the Qatar Peninsula. Recharge was from areas of high tritium (stippled on the map) to areas of low tritium. (From Yurtsever and Payne, 1979.)...

Borole et al. (1979) presented another example of a regional aquifer with 14C ages increasing down-gradient. Figure 11.13 reveals a water table map of the... 

Dermis (1973) studied the impact of a stockpile of 50,000 tons of salt used for highway deicing at Mars Hill, Indianapolis, Indiana. The salt was stored in 1966 and removed in 1968 because the local aquifer turned saline (several thousand mg Cl/1). The aquifer recovered gradually. In 1976 the water of most wells was potable, but traces of the contamination were still reflected in an isochlor contour map (Fig. 16.21). 

Figure 1 Map showing the location of wells and directions of groundwater flow. Snake River Plain aquifer, Idaho...

Figure 4 Map showing the prepumping potentiometric surface of the Floridan aquifer and locations of wells shown...

Figure 1. Map of south and east Asia showing the distributions of recognised aquifers containing high-arsenic groundwaters. The shaded area represents the Himalaya and associated uplands.

Predevelopment water-level map of the Santa Fe Group aquifer system in the Middle Rio Grande Basin between Cochiti Lake and San Acacia, New Mexico, U.S. Geological Survey Water-Resources Investigations Report, p. 1 sheet. 

Schombel, L. F., 1994, Bedrock and alluvial aquifer saturated thickness isopach maps in Wossner, W. W., ed. Missoula, Montana, Montana Department of Justice, Natural Resource Damage Litigation Program, p. 130. 

In the Floridan aquifer, traces of gypsum are present in the carbonate rock. The high calcium concentration from gypsum dissolution exceeds its value at saturation with calcite, leading to precipitation of the carbonate and the production of additional CO2 (reaction 8). Concurrently, anaerobic decay of buried organic matter (reaction 3) and sulfate reduction (reaction 6) take place. The combination of these processes has caused an increase in the CO2 pressure of the groundwater from 10" bar in the recharge zone to 10" bar downdip as the pH decreases from 8.0 to 7.4 over a map distance of 115 km (Fig. 5.3) (cf. Back and Hanshaw 1970 Plummer et al. 1983). 

We selected a few sections containing wells for which analyses can provide some information about the groundwater flow. Fig. 4 is a water-level map of the Madrid aquifer and Fig. 5 shows three sections, along directions which are parallel to the water flow as deduced from the equipotential lines in Fig. 4. 

The radiometric ages (piston model) have been used in the map of Fig. 9. Isochrons of 0.5 "IO, 10 , 1.5 "lO, 2 10 and 3 10 yr. have been drawn. The confined aquifer may be divided into four sections bounded by faults where the rates of circulation are quite different. 

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