The very process of exploring to characterize or define small-scale properties of substrata at contaminated, disposal, or construction sites is unique to geotechnics in general and environmental geotechnology specifically. Unlike other engineering endeavors, where material properties are specified during design, manipulation of the subsurface must contend with preexisting - but undefined - conditions, and exploration is necessary to estimate those unknown properties. Quantitative methods are being developed for evaluating the effectiveness of site characterization activities by investigating variation in predicted performance with reduced variation in measured site properties. Sources of uncertainty in site properties include spatial variation, measurement noise, estimation error, and measurement bias. Hypothetical changes in the measurement scheme are evaluated for their effect on the variation and mean of predicted project performance. This structured approach involves use of three-dimensional geostatistics, separation of sources of property variation, as well as analyses of project performance.

Related Publications by C.H. Dowding

"Geostatistical Guidance of Exploration in Roof Control - How Many Drill Holes are Enough ?" (with C.T. Leduina) Proceedings of Fifth Conference on Ground Control for Midwestern Coal Mines , Southern Illinois University, 1994.

"Fractures and Fracture Patterns," Encylopedia of Field and General Geology, Van Nostrand Reinhold Co., New York, 1986.

"Comparison of Predicted and Encountered Geology for Seven Colorado Tunnels," Proceedings of the Rapid Excavation and Tunneling Conference, AIME, 1976.

Feasibility of Horizontal Boring for Site Investigation in Soil, Final Report DOT Contract DOT-FH-118526, 1976.

Environmental Geotechnics Home Page
Environmental Geotechnics Research Projects Page
Civil and Environmental Engineering Home Page

For more information contact:
Dr. Charles H. Dowding