The relationships among water potential, hydraulic conductivity, and water content (t-K-8) are some of the most important and commonly sought soil physical properties in agricultural, environmental, and engineering applications. These applications generally center around water and contaminant transport. Predication of water and solute movement in these applications is ultimately predicated upon adequate experimental data. Current methods of obtaining this information are time- consuming, expensive, and often yield inaccurate parameter estimates. Therefore, in Phase I, we designed, built, and performed preliminary testing on a one-step cell to achieve the following objectives: 1) rapid experimental results, 2) improved experimental precision, 3) reduced labor for experimentation and analysis, and 4) improved accuracy in parameter estimates. The one-step device consists of an innovative cell design coupled with a datalogger. Data acquisition is event controlled. The system automatically starts and stops the experiment. Time, outflow, and surface potential are recorded at user-specified weight-change increments. I Based upon the encouraging Phase I results, we propose to develop, construct, distribute, and test a one-step outflow system in conjunction with collaborating specialists. The final product will be a practical flexible tool for commercial and research applications.
Anticipated Results:Groundwater pollution is a critical national environmental issue. Increasing pressures and demands on soil and water resources have resulted in interest from researches, consultants, and regulators in methods to accurately predict water and chemical movement. A consensus exists that the quantity and quality of information used to make projections and decisions needs improvement. Current methods of obtaining soil hydraulic properties are slow, labor intensive, and subject to criticism. Development of improved methods for determination of soil hydraulic properties will improve decision-making in the environmental industry and provide a cost-effective research tool.