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HYDROGEOLOGY OF AQUITARDS AND
LOW-PERMEABILITY MATERIALS:
Part 1, Analysis of Aquitard Integrity

We face a common problem: how many times have you learned of a shallow groundwater contamination problem and heard someone say "We don't have to worry about the deep aquifer, it is protected by an overlying aquitard"

How many times have you seen cross sections showing that downward migration of contaminants stops at a clay or shale layer? Have you ever really investigated these aquitards? How do you know they are effective barriers to contaminant movement?

Aquitards are critically important for understanding groundwater protection, drinking water supplies, and contaminant movement. Although aquitards may seem to make up only minor parts of hydrostratigraphic sequences they commonly control the overall groundwater flow system by influencing recharge, discharge, vertical head distributions, groundwater flow paths, and contaminant migration. During this 2-part webinar series, you will:

• Discover the unique hydraulic properties of low-permeability units.
  
  
• Learn about recent advances for testing aquitard integrity and apply it to your monitoring or ground water supply protection program.
  
  
• Avoid common mistakes related to characterizing ground water movement and contaminant pathways in low-permeability units.

Both unconsolidated and bedrock aquitards share inherent low hydraulic conductivities, but approaches and field methods for characterizing each type can be completely different. This 2-part webinar series will unravel the complexity of aquitards and their hydrogeologic and hydraulic relationships.

Applications:

• Hydrogeologic Characterization
• Contaminant Investigation
• Remediation
• Water Supply
• Engineering Design

Highlights from Part One include:

• Aquifers and Aquitards: the importance of aquitards in all groundwater projects
• Definitions and basic categories of aquitards
• Hydrostratigraphic relationships and hydrogeologic context
• Definitions of aquitard integrity
• Keys to aquitard evaluation
• Defining the water table in low-permeability settings
• Do's and Don't's of monitoring aquitards
• How aquitards control groundwater flow system

Highlights from Part Two include:

• Do's and Don'ts of monitoring aquitards
• Relationships between hydraulic gradients, hydraulic conductivity, and groundwater flow rates
• Effects of transient conditions
• Evidence for (and against) perched conditions
• Contaminant transport across aquitards
• Do's and Don'ts of calculating solute transport in aquitards
• Example problem

Protect yourself, your company and your clients by learning how to assess which parts of the formation control aquitard integrity. The simple key to these concepts is correctly evaluating aquitard integrity.

Discover these hydrogeologic tools that are found no where else on the web.

A Record of Attendance Form is included free with each webinar for your record keeping and individual PDH verification. We ask your on-site coordinator to return the completed and signed copy of the Form to us following the webinar for (1) maintaining a separate copy as a service to attendees and (2) forwarding to NIU confirming attendance for those who order certificates.

Attendees may also order an official a Course Completion Certificate from Northern Illinois University for a small administrative fee. The Certificate is optional and may be ordered separately following the webinar to confirm your attendance and showcase the certificate on your office wall. Instructions for ordering certificates are given during the webinar.


* This webinar is eligible for the 'BUY THREE, GET THREE' discount; however ANY webinar series discount shown above cannot be combined with it.

Attendees will be invited to actively participate during this live and interactive on-line web seminar. Discussion is planned following the webinar for those who want to continue the session. Bring your questions to the webinar and present them to the instructor and other participants for exploring the best solution.

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Instructors Bio

David Hart, PhD, PG

Dave Hart is a hydrogeologist/geophysicist with the Wisconsin Geological and Natural History Survey and an associate professor at the University of Wisconsin-Extension.

Dave's applied research includes regional groundwater flow and recharge in southeastern Wisconsin, near-surface geophysics, and measurement of porosities and permeabilities in aquifers and aquitards. Prior to joining the university, he served as a hydrogeologist with Eder Associates. He is an associate editor for Ground Water and past president of the AWRA - Wisconsin Section.

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Madeline Gotkowitz, PhD
Hydrogeologist, Wisconsin Geological and Natural History Survey
Associate Professor, University of Wisconsin - Extension

Madeline Gotkowitz is a research scientist at the Wisconsin Geological and Natural History Survey, where her work focuses on regional groundwater flow and transport modeling, subsurface fate and transport of human enteric viruses, and flow and transport across aquitards. Gotkowitz's field-based investigations of arsenic in groundwater address conditions in surficial and bedrock aquifers, and the affect of well disinfection on arsenic release. Gotkowitz holds a B.A. in Environmental Sciences from Smith College and an M.S. in Hydrology from New Mexico Institute of Mining and Technology.