Hydrogeologic Framework and Simulation of Ground-Water Flow and Travel Time in the Shallow Aquifer System in the Area of Naval Support Activity Memphis, Millington, Tennessee 

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List of Figures

1. Map showing location of Naval Support Activity Memphis, Millington, Tennessee
 

2. Map showing locations of 13 Solid Waste Management Units, 9 stratigraphic test holes, and 4 water-level observation wells at Naval Support Activity Memphis, Millington, Tennessee
 

3. Map showing location of model area, principal surface-water drainages, and wells in which water-level measurements were made in April and October 1996 near Naval Support Activity Memphis, Millington, Tennessee
 

4a. Map showing locations of geologic sections A-A´, B-B´, and C-C´, and faults that displace the Cockfield and Cook Mountain Formations and Memphis Sand at Naval Support Activity Memphis, Millington, Tennessee
 

4b. Geologic sections A-A´, B-B´, and C-C´, and geophysical logs of test holes or wells in the area of Naval Support Activity Memphis, Millington, Tennessee
 

5. Map showing locations of test holes or wells for which analyses of core samples, aquifer or specific-capacity tests, or water-quality samples are available for stratigraphic units beneath Naval Support Activity Memphis, Millington, Tennessee
 

6. Hydrographs showing water levels recorded in wells Sh:U-100, Sh:U-101, and Sh:U-102, and daily precipitation at Naval Support Activity Memphis, May 1995 through September 1996
 

7. Map showing altitude of base of sand and gravel in lower alluvium or fluvial deposits at Naval Support Activity Memphis, Millington, Tennessee
 

8. Map showing thickness of sand and gravel in lower alluvium or fluvial deposits at Naval Support Activity Memphis, Millington, Tennessee
 

9. Map showing altitude of the potentiometric surface of the alluvial-fluvial deposits aquifer at Naval Support Activity Memphis, Millington, Tennessee, April 1996
 

10. Map showing altitude of the potentiometric surface of the alluvial-fluvial deposits aquifer at Naval Support Activity Memphis, Millington, Tennessee, October 1996
 

11. Map showing thickness of the Cockfield Formation and locations of faults that displace the Cockfield and Cook Mountain Formations at Naval Support Activity Memphis, Millington, Tennessee
 

12. Map showing altitude of base of Cockfield Formation (top of Cook Mountain Formation) and locations of faults that displace these formations at Naval Support Activity Memphis, Millington, Tennessee
 

13. Map showing altitude of the potentiometric surface of the Memphis aquifer in northern Shelby County near Naval Support Activity Memphis, Millington, Tennessee
 

14. Map showing altitude of the potentiometric surface of the alluvial-fluvial deposits aquifer, April 1996, and faults that affect water movement at Naval Support Activity Memphis, Millington, Tennessee
 

15a. Diagram showing borehole geophysical logs of test hole 1 (Sh:V-74) and hydrogeologic units of the shallow aquifer system southwest of the erosional scarp at Naval Support Activity Memphis, Millington, Tennessee
 

15b. Diagram showing borehole geophysical logs of test hole 6 (Sh:V-78) and hydrogeologic units of the shallow aquifer system northeast of the erosional scarp at Naval Support Activity Memphis, Millington, Tennessee
 

16. Hydrogeologic section B-B´ showing the aquifers and confining units in the shallow aquifer system at Naval Support Activity Memphis, Millington, Tennessee
 

17. Map showing model grid, wells used to calibrate model, cells simulating fault, location of a simulated window in Cook Mountain confining unit, and boundary conditions for the flow model of the shallow aquifer system in the area of Naval Support Activity Memphis, Millington, Tennessee
 

18. Diagram showing hydrogeologic framework of the flow model of the shallow aquifer system in the area of Naval Support Activity Memphis, Millington, Tennessee
 

19. Map showing transmissivity array for layer 1 of the calibrated flow model and locations of cells simulating buried river valleys in the area of Naval Support Activity Memphis, Millington, Tennessee
 

20. Map showing transmissivity array for layer 2 of the calibrated flow model of the shallow aquifer system in the area of Naval Support Activity Memphis, Millington, Tennessee
 

21.Graph showing simulated water levels generated by the calibrated flow model and mean water levels in the alluvial-fluvial deposits aquifer in the area of Naval Support Activity Memphis, Millington, Tennessee
 

22. Map showing altitude of the simulated potentiometric surface of layer 1 of the calibrated flow model of the shallow aquifer system in the area of Naval Support Activity Memphis, Millington, Tennessee
 

23. Map showing results of particle-tracking analysis of ground-water-flow directions in layer 1 of the calibrated flow model of the shallow aquifer system in the area of Naval Support Activity Memphis, Millington, Tennessee
 

24. Map showing locations where particle-tracking analyses were performed for layer 1 of the calibrated flow model of the shallow aquifer system in the area of Naval Support Activity Memphis, Millington, Tennessee
 

25. Map showing locations of selected hypothesized plumes of contamination in the alluvial-fluvial deposits aquifer at two sites within the Northside Area of Concern at Naval Support Activity Memphis, Millington, Tennessee
 

26. Map showing results of particle-tracking analysis at the former N-6 hangar area and the grassy area near Solid Waste Management Unit 7, showing location of 40-year time-of-travel and pathlines of particles in layer 1 of the calibrated flow model of the shallow aquifer system at Naval Support Activity Memphis, Millington, Tennessee
 

27. Map showing results of particle-tracking analysis at Solid Waste Management Unit 2, showing 40-year time-of-travel and pathlines of particles in layer 1 of the calibrated flow model of the shallow aquifer system at Naval Support Activity Memphis, Millington, Tennessee