2016 NGWA Groundwater Summit

Pressure Transducers - Common Data Issues and How to Avoid Them

Monday, April 25, 2016: 2:20 p.m.
Confluence Ballroom B (The Westin Denver Downtown)
Sonya Cadle, P.G. , Tetra Tech, Louisville, CO
Guy Roemer, P.E. , Tetra Tech, Louisville, CO

Pressure transducers are used worldwide to collect data during groundwater monitoring and aquifer testing. These instruments have proven to be invaluable tools for hydrogeological analysis. However, the data collected can be of poor quality or may be rendered unusable as a result of common errors made during transducer selection, programming, installation, and download. In addition, improper transducer data manipulation can lead to erroneous conclusions. These problems have resulted in increased project costs and, in some cases, have resulted in distrust of transducer data collection.

Thousands of transducer data sets collected during aquifer testing and long-term groundwater monitoring were reviewed to distill key lessons learned that can be applied to any site.  When selecting a transducer, consideration must be given to factors such as the goal of the data collection effort, site-specific factors such as lithology and well completions, and the software interface of the instrument. Transducer programming, installation, and download must be planned in a fashion that makes successful data collection as easy and convenient as feasible, and the field staff should be trained to recognize and mitigate common problems they might encounter. Careful documentation is critical during the field effort. When problematic data are collected, the field documentation becomes a vital tool to successfully analyze the data despite its problems. A number of potentially catastrophic problems can be fixed during analysis if good field documentation is available.

Sonya Cadle, P.G., Tetra Tech, Louisville, CO
Sonya Cadle has 15 years of professional experience in environmental geology and hydrogeology. Ms. Cadle's typical duties include groundwater flow and contaminant transport modeling, aquifer testing and analysis, and long-term monitoring network design and management. She is often involved in characterizing sites with complex hydrogeological environments and uses various software tools to assess site conditions, remedial options, water resource availability, and dewatering needs.

Guy Roemer, P.E., Tetra Tech, Louisville, CO
Mr. Roemer is a Senior Environmental Engineer with 18 years of professional hydrogeology experience in United States, Canada, and Australia. Mr. Roemer’s primary duties are conducting groundwater flow and transport modeling for proposed and reclaimed mines, water rights issues, assessing long-term impacts on regional aquifers and streams, water supply availability, pit dewatering and pit lake formation, and evaluating the effectiveness of remedial activities at mines and contaminated sites. Mr. Roemer also reviews groundwater flow and transport models for governmental agencies and private industry. Mr. Roemer’s other professional duties include project management, seepage modeling, aquifer testing, dynamic systems modeling, litigation support, aquifer test analysis, and development of Access and GIS databases.