Principles of Hydrogeology (ESCI 337)

Fall 2016

Drawing Hydrogeologic Cross SectionsSanders

Warning:"The Situation" described in this problem isentirely fictitious. Do not discuss this project with any residents, government entities, or other people with any connection whatsoever to this area.
The Situation:Your clients are the developers of a proposed 100-home housing development in an exurban area. The County and Township government have informed them that they must provide their own water source for the residents of the development, and they cannot tie in to existing water systems. They would like to use a surficial aquifer in the area of the development, and they want to know more about its characteristics and potential for use. They ask you to study the hydrogeology of the area and create a model so they can investigate different pumping scenarios.
Your Task:Collect geologic data and create cross sections that illustrate the geologic and hydrogeologic setting of the study area. Your cross sections should portray the hydrogeologic system--that is, you should be looking for flow system boundaries. Keep that in mind as you decide how far a cross section should extend.
The property boundaries are not firmly established yet, because the developer plans to purchase as much or as little property for the well field as is needed. The general area is near Bolingbrook and Naperville, Illinois, and the site they are considering falls roughly between127th St, 119th Street/Rodeo Dr., the DuPage River (near Naperville Road, also called Plainfield-Naperville Road or Rte. 14), and the border of a housing development that fronts on Route 59.
Cross Section Format Information:
Cross sections should extend from point to point,not necessarily in a straight line. (Some call this a "fence diagram" instead of a cross section.) Use as many points as you need to represent the system.
The following should be shown on cross sections:

  • Elevation scales (one on each side of the drawing)
  • Horizontal scale (a graphical bar scale)
  • Statement of vertical exaggeration (for example, "Vertical Exaggeration = x25", or "Vertical Exaggeration = 50:1")
  • The ground surface topography
  • Letters designating the line along which the cross section is drawn--for example, A-A', or B-B'.
  • Single black lines outlining lithostratigraphic and/or hydrostratigraphic units (do notfill the area with a pattern)
  • A label for each geologic unit portrayed. If you know the formal formation name, give it; otherwise, use a label such as "Clay", "Granite", etc.
  • A label for any significant local features, for example, lakes, streams, county lines, major highways, and so on.
  • A single, solid, black line showing the location and depth of each well that appears on cross section; at the top, give the five-digit unique number code for that well (digits six through ten of the "API number").
  • Total depth of each well that appears on the cross section (print "TD = __" at the bottom of each well).
  • Ideally, the cross section should fit on one sheet of 11" x17" paper (or smaller).
  • On a separate sheet, give a map showing the line of cross section. Be sure to label the lines as A-A' or B-B' .

Draw your cross sectionIN PENCIL!!!!IN PENCIL!!!!IN PENCIL!!!!(You probably will have to change it after it is reviewed.)
You may find it helpful to download a topographic map of the area ( orto use GoogleEarth Pro (earth.google.com).

We will be working on this project in class next week, but you should come in with much of the research already done. By the end of class on Tuesday, you should have delineated the boundaries of the flow system, collected all the boring log data you need, identified the hydrostratigraphic units, and sketched out cross sections. You also may wish to get a start on the final drawing.
Please cooperate with each other to collect data and analyze the problem. However, each person is responsible for his/her own cross section drawing.