SWISS - Innovative Discrete Interval Sampling Technology for Detection and Assessment of Pathogens and Contaminants in Soils and Ground Water

Waterborne diseases are likely to be contracted when ground water contaminated with pathogenic microorganisms is consumed, and with over half of the U.S. population relying on water sources derived from ground water, sampling and detection is of critical importance. Similar difficulties in sampling, detection, and assessment of pathogens occur as with other contaminants in soil and groundwater. The Shedd-Weikel Interval Sampling System (SWISS) aids in sample collection, detection, and assessment by creating interval isolation and mitigating the possibility of cross-contamination without the costs and difficulties associated with installation and use of currently available interval sampling systems.

The SWISS technology is simple, taking little more effort than typical well installation. Casing is placed into the boring along with screen at the intervals to be discretely monitored and sampled, and is constructed of gravel pack within the discrete zones and intermediate seals between the discrete zones within the annular space. A custom designed core system constructed of rigid stem with rubber packer cups are then placed into the casing. The stem is ported at each discrete zone in order to allow for sample collection and packer cups are placed above and below the discrete zones. The technology allows for a testable seal within the well, provides the predictable characteristics of a standard well structure, and allows the option for removal and abandonment if cross-contamination is detected. Flexible tubing is installed from each interval to the surface to allow for quick and efficient sampling from each zone. Optional in-line components can be installed for various applications.

The SWISS relies on proven oil-field and water industry materials and an innovative custom design to yield a simple, cost effective solution for discrete zone sampling and isolation. Prototyping of the technology is planned with applications for a wide range of hydrogeologic environments.