Print the questions and the map. They are in the same pdf document.

Magic Gulch Water and Waste Problem
NAME: ________________
The attached map illustrates the confluence of two streams near a small rural
development called Magic Gulch. Contours on the map are estimated levels of the
water table (WT). The water table level at 1100m near the south edge of Magic
Gulch community represents the ambient WT in a regional, fairly homogeneous,
aquifer which lies beneath the town. The current water supply is WELL #1. In the
early 1900's, a small mine was operated in the southwest part of the map. The
miners also used a nearby pit as a dump for about 30 years before the mine shut
down. All operational refuse went into the dump and a pile of mine tailings
(crushed rock) is located at the mine entrance.
City planners in Magic Gulch obtained water tests from WELL #1 and found it to
contain excessive levels of zinc, cadmium and copper (among other constituents),
so they want to drill a new town well at the WELL #2 site. Hydrologists suggest
that pumping the same amount of water from WELL #2 as they are currently
pumping from WELL #1 will create a cone of depression that is 100 meters in
diameter after equilibrium is reached during continual pumping.
EXERCISE -- Draw on the attached map and answer questions on this page. Use
the backside for additional space.
1. Draw water table flow lines from each of five points (A-E) on the map to
produce a simple flow net of the area.
2. What is the average WT gradient between the mine and the river
3. Using the data available, determine the velocity of contaminants (leachate) from
the mine through the groundwater system once they have reached the saturated
zone.
4. Once any new leachate from the mine infiltrates to the saturated zone, how long
does it take for it to reach the river
5. Well #1 is across the river from the mine. What hydrologic reason(s) are there to
suspect mine waste as the source of potential contaminants in the well water
6. What is the average WT gradient and velocity of groundwater between the dump
and the river How long would it take for dump leachate to reach the river once it
is in the saturated zone

7. Is the new well a good site for their water supply Why or why not Answer in
terms of the distance from estimated flow lines to the cone of depression and the
likelihood of chemical dispersion.
8. What additional information would be useful to evaluate this problem
MAGIC GULCH MAP