water table contour map
Water Quality Exercise Background
This exercise involves drawing a groundwater contour map of the depth to the water table. 1. To find the elevation of the water table at each site, you need to subtract the depth to groundwater from the elevation of land surface at each site in the table above. Example: top of well A elevation = 160.6 feet depth to groundwater = 8.6 feet -‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐ elev. of water table = 152 feet 2. Determine the water table elevation for each well in the table above. 3. Print one copy of the site map (accesss under Groundwater Quality), and write in the groundwater elevations at each well (write in pen). 4. Using PENCIL, contour the groundwater elevations using a contour interval of 2 feet. Label each contour line. 5. Determine the direction of groundwater flow (perpendicular to the contour lines and down the slope of the groundwater table), and draw an arrow that indicates flow direction. 6. Contaminants (in this case Trichloroethylene or TCE) are transported in the direction of groundwater flow. To learn more about the properties and uses of TCE visit Wikipedia. 7. Submit your completed water table elevation map as a PDF or scan in dropbox.
Well Elevation of Top
of Well (ft) Water Level (ft) Elevation of Water
Table (ft) Trichloroethylene
(ppb) A 160.6 8.6 152 0 B 163.2 10.6 0 C 159 9.3 0 D 158.1 7.8 0 E 153.2 5.6 145.5 F 157 9 167.9 G 155.4 7.7 0 H 155.6 8.4 192.1 I 155.4 9.7 12.2 J 153.7 7.6 0 K 152.2 6.9 0 L 152.6 8.8 0 M 153 8 2.1 N 149.5 7.4 0 O 150.8 8.5 0