Lecture 32
High Plains Aquifer
Add 7.8-7.12
Influence of stratigraphy on Regional flow
Ground-water discharge flowing freely, naturally, springs.
Figure 8.8 Ground-water flow in an aquifer with concentrated
discharge. A. Flow in an isotropic aquifer. B. Flow in an anisotropic
aquifer with the horizontal hydraulic conductivity ten times the vertical.
Source: R.A. Freeze & P.A. Witherspoon, Water Resources
Figure 8.9 Regional ground-water flow in layered aquifers. the greater
proportion of the flow occurs in the layer with higher hydraulic conductivity.
Source: R.A. Freeze & P.A. Witherspoon, Water Resources Research 3
Figure 8.10 Regional ground-water flow in confined aquifers: A. Aquifer
confined by a sloping confining layer. B. Aquifer confined by a flat-lying
confining layer. Source: R.A. Freeze & P.A. Witherspoon, Water
Resources Research 3 (1967): 623-34.
High Plains Aquifer-
Ogalalla Formation- water table aquifer
Recharge-
rainfall 16 in West in the 28 inches East
ET greatly exceeds rain.
® Recharge 0.024 in/yr (Texas) 6 in/yr (Kansas)
K, Sy Vary spatially, Ogalalla deposited by streams.
K = 25 - 300 ft/d, Sy = 5 - 30%
Water table slopes- due to regional topography
v = 1 ft/d
b ~ 0 feet at W ® 1,000 feet in Nebraska
Pumping may be 2-100 times recharge in some areas
-mostly in TX and Ks
Water quality declines generally with greater depth.
Figure 8.20 Principal geologic units of the High Plains
aquifer. Source: E.D. Gutentag, F.J. Heimes, N.C.
Krothe, R.R. Luckey, & J.B. Weeks, U.S. Geological
Survey Professional Paper 1400-B, 1984.
Figure 8.21 Aerial distribution of hydraulic conductivity in
the High Plains aquifer. Source: E.D. Gutentag, F.J. Heimes,
N.C. Krothe, R.R. Luckey, & J.B. Weeks, U.S. Geological
Survey Professional Paper 1400-B, 1984.
Figure 8.22 Water table in the High Plains aquifer, 1980.
Source: E.D. Gutentag, F.J. Heimes, N.C. Krothe, R.R. Luckey,
& J.B. Weeks, U.S. Geological Survey Professional Paper
Figure 8.23 Water-level changes in the High Plains aquifer,
predevelopment to 1980. Source: E.D. Gutentag, F.J. Heimes,
N.C. Krothe, R.R. Luckey, & J.B. Weeks, U.S. Geological
Survey Professional Paper 1400-B, 1984.
Geohydrologic sections through the High Plains aquifer (from Weeks and
Geology, regional flow, and simulation of flow in the Palo Duro Basin.
Geology (a) and simulation of flow (c) from Senger and others, (1987);
regional flow (b) from Bair (1987).
Potential repository sites considered for high-level nuclear waste repository.
Map of Nevada showing location of Yucca Mountain.
Physiographic features of the Nevada test site.
Generalized ground-water subbasins of the Death Valley Ground-water Basin.
Exploratory studies facility design at Yucca Mountain.
Conceptual unsaturated zone flow model for Yucca Mountain.
Composite potentiometric surface for the Nevada Test Site.
Generalized ground-water flow beneath the Nevada Test Site.
Positive Features of Yucca Mountain
 |
Repository Would be in Unsaturated Zone |
|
Desert Environment |
|
Zeolite Minerals Present |
|
Remote Location |
|
Scientific studies are not likely to impact the environment |
Potentially Adverse Conditions
|
Site Relatively Difficult to Characterize and Model |
|
Evidence of Active Faulting and past Volcanic Activity |
.gif){kind=small}
ENV 302 - Lectures
