Wednesday, December 5, 2007 : 10:20 a.m.

Innovative Cost-Effective Ground Water Monitoring Well Design

Thomas D. Dalzell, CWD, AMS, Mark Kram, Ph.D., ESM, CGWP, U.S. Navy and Jeffrey A. Farrar, M.S., PE, U.S. Bureau of Reclamation

For proper groundwater monitoring well design, ASTM D5092 recommends that drillers collect soil samples from candidate screen zones, conduct sieve analyses, and use selected grain size diameter values to determine appropriate filter pack gradation and screen slot size requirements. The recommended well design approach described in D5092 requires additional time in the field, and typically implies an additional costly field mobilization effort.  As a consequence, most drillers omit this critical step.  Therefore, the majority of monitoring wells are not designed appropriately to match the formation screened, resulting in ground water samples that are improperly filtered.  The consequences with respect to well longevity, hydraulic performance, and sample integrity could be profound.  Researchers from the Navy and Bureau of Reclamation have developed a rapid method for designing monitoring wells using high-resolution piezocone derived soil type classifications. This innovative probe and software system allows the user to select appropriate filter pack and slot size specifications tailored to candidate screen depth ranges without the need for collecting soil samples or additional deployments.  This innovative approach will be described, and examples and cost comparisons presented.

Thomas D. Dalzell, CWD, AMS Mr. Dalzell has more than twenty years of experience in the environmental field. He works in the PowerProbe Direct Push Research and Development Department for AMS. His experience at AMS includes initial design and testing of new products and improvement of existing products. He also conducts training and demonstrations for customers, universities, and regulatory agencies. His specialties and past work experience has been, but is not limited to: geology; subsurface site characterization and remedial investigations; and groundwater investigations and monitoring programs. Mr. Dalzell also has been involved with the direction of field activities for various environmental projects.

Mark Kram, Ph.D., ESM, CGWP, U.S. Navy Dr. Mark Kram is a hydrogeologist for the US Navy specializing in environmental site characterization and remedial design. Dr. Kram has over 20 years of experience using environmental assessment techniques and has authored papers, national standards, articles and book chapters on the subject. He has been instrumental in the areas of dense non-aqueous phase liquid (DNAPL) site characterization, chemical field screening, and monitoring well design, and holds several patents for hydrogeologic and chemical characterization tools and methods. Most recently, Dr. Kram served as the Technical Lead on the ESTCP Direct Push Well Comparison project.

Jeffrey A. Farrar, M.S., PE, U.S. Bureau of Reclamation Mr. Farrar has more than twenty-nine years of involvement in the geotechnical and environmental fields. He works as Geotechnical Engineer for the Earth Sciences and Research Laboratory – U.S. Bureau of Reclamation (USBR), in Denver, Colorado. His experience at the USBR includes technical specialist oversight for geotechnical, environmental, earthwork control, and earthquake engineering site investigation activities. He is currently the chairman of the ASTM subcommittee D18.21 on Groundwater and Vadose Zone investigations. He has written numerous test standards and texts on geotechnical and environmental site characterization. Mr. Farrar also provides assistance to numerous government agencies in his areas of expertise.


2007 NGWA Ground Water Expo and Annual Meeting