1. Two types of uncertainty analysis Uncertainty in the calibration. This is usually called a sensitivity analysis Uncertainty in the prediction. This is usually called an uncertainty analysis.

2. Sensitivity Analysis Z&B

3. Uncertainty in Prediction Z&B

4. PDF CDF Z&B

5. Monte Carlo Analysis Z&B

6. PDF CDF Z&B

7. Hydraulic conductivity Initial concentrations (plume configuration) Both Z&B

8. Reducing Uncertainty Hard data only Soft and hard data With inverse flow modeling Hypothetical example truth Z&B

9. “Truth lies at the bottom of a bottomless pit.” J. Facher, attorney for Beatrice, Woburn Trial “One more run…” “…knowledge competes with resolution…” L.N. Hughes, Federal Judge