| 1. Photo of ALPART's bauxite processing plant at Nain |
| 2. Location Map showing Mandeville, Nain,
waste ponds, and groups of NWC and ALPART wells |
| 3. Schematic map showing ground water use and
circulation between bauxite plant, ponds and domestic water supply wells
|
| 4. Cros section through limestone aquifer from
south to north, showing elevation differences between industrial waste ponds,
and abstraction (pumping) sites. |
| 5. Map showing distribution of sodium near
waste ponds in December 1999. |
| 6. Concentration of Na and Cl and pH value versus
time at one of ALPART's wells in the period 1988-1999. |
| 7. Na, Cl, and pH values at New Forrest well.
|
| 8. Increase of Na at one of ALPART's industrial
wells, located about 5 km north of waste ponds. |
| 9. Mathematical Model: Heads in limestone aquifer under pristine
conditions (no pumping, no contamination). Velocity vectors and pathlines.
|
| 10. Model: Heads and velocity vectors in zoomed-in area around
waste ponds and bauxite plant. No pumping. No contamination.
|
| 11. Model: Steady-state distribution of heads
under current pumping conditions (ALPArt at Nain and at Pepper, NWC at Pepper-Goshen).
|
| 12. Model Phase Three: Extension of
contaminant plumes after 5, 10, 15, and 20 years of simulation. Shown are the
leading edges of the plume with Na between 50 and 100 ppm.
|
| 13. Phase Three: Pathlines from waste ponds toward wells.
|
| 14. Phase Three: Na concentration with time
at Nain-3. |
| 15. Field observed Na concentrations at Nain 3
for comparison with map 13.
|
| 16. Phase Three: Na concentration with time at
ALPART's wells 8 and 9. |
| 17. Field observed Na concentrations at ALPART's
well 9 for comparison with map 15. |
| 18. Field observed Na concentrations at ALPART's
well 8 for comparison with map 15. |
| 19. Model Phase Four: Plume extension after
20 years of pumping. Only NWC wells are pumping. ALPART's wells stopped pumping
but contamination with Na continues. |
| 20. Model Phase Four: Na concentration with
time at one of NWC wells at Pepper. |
| 21. Model Phase Five: Distribution of heads
and velocity vectors after 30 years of pumping. ALPART's wells stopped pumping
after 20 years. Na release into ponds also stopped after 20 years.
|
| 22. Model Phase Five: Na plume extension
after 30 years. Parameters and boundary conditions at one of Pepper wells.
|
| 23. Model Phase Five: Na concentration with
time at NWC wells. |
| 24. Distribution of bauxites in Jamaica and Essex Valley Model Area. |
