The results of a ground-water monitoring project are based on samples collected from monitoring wells. The wells must be properly installed, constructed, and placed in accordance with project objectives and goals. Ground-water sampling must be conducted such that a representative sample is consistently obtained. Ground-water monitoring system design considerations include project goals and objectives, geology, hydrologic characteristics, chemical parameters to be monitored, and analysis and evaluation plans. To achieve a high-quality monitoring project with the capability of meeting project goals and objectives, the integration of a number of disciplines is necessary. Hydrogeologists, geologists, chemists, statisticians, engineers, and trained and experienced technical field personnel all provide valuable input.

A Comprehensive Monitoring and Evaluation project designed to detect changes in nitrogen and pesticide concentrations from agricultural activities is underway in eastern South Dakota. The geology and sampling situations encountered vary considerably throughout the project area. Experience gained through this project and techniques and methodologies applicable to ground-water monitoring are presented.