Alaska Section, American Water Resources Association

Richard Kemnitz, Alaska Section AWRA Northern-Region Director

I would like to invite you to the January 2000 Brown-Bag presentation by David L. Barnes, Department of Civil and Environmental Engineering, University of Alaska Fairbanks. Please note this meeting is the second Wednesday in January. David's talk will be a presentation design uncertainty issues associated with waste management systems. We look forward to seeing you. Please feel free to bring a colleague to the meeting.

January 10, 2000
Alaska Section AWRA, Northern-Region Brown-Bag Presentation
Alaska Department of Natural Resources, Large Conference Room
Noon to 1300

"Design of Waste Management Systems Under Conditions of Uncertainty"
David L. Barnes, Department of Civil and Environmental Engineering, University of Alaska Fairbanks

In the last ten to fifteen years a large amount of attention has been given to the problem of cleaning up soils and groundwater that have been impacted by poor waste management practices. Systems that are designed to reduce the impact of past poor waste management practices are known to be costly. Thus, engineers have been tasked with designing economical systems that have a high probability of accomplishing the intended goal. Also, because of the amount of money that has been appropriated to restoring (partially or fully) contaminated environments, engineers are now searching for better methods of designing waste management facilities such that these problems do not recur. One of the challenges facing engineers designing these types of systems is the incomplete knowledge of the hydrogeological properties pertaining to the porous media in which these systems will be installed. Without a good understanding of these properties the engineer may have difficulty designing capable economical systems.

The use of a systems analysis procedure called decision theory is a relatively new approach that has been applied to the design of waste management facilities and restoration systems when the properties of the hydrogeological environment are uncertain. This cost-risk-benefit methodology enables the engineer to select an optimum design out of a finite set of designs when incomplete knoweldge of the hydrogeological properties prevail. To date this approach has been applied only to the saturated zone. A methodology has been developed by the author for the application of this design concept to systems that impact the unsaturated zone - specifically soil vapor extraction. The purpose of this presentation is to introduce the concept of design using decision theory and show the applicability of the design approach with an example.