We are pleased to announce the publication of a new article in Groundwater Monitoring and Remediation from the G360 Institute Team.
Novel Well Completions in Small Diameter Coreholes Created Using Portable Rock Drills:
Pierce*, A.A., Parker, B.L., Ingleton, R., Cherry, J.A.
DOI: 10.1111/gwmr.12257
Acknowledgments
We thank Neil Shaw, CEO of Shaw Drills, for his devotion to quickly advancing his drill to make 2-inch diameter holes, which allows use of down-hole pressure transducers, and his continued work on modifying the drill technology to enhance its capabilities for use in hydrogeological studies. Dale Emerson of Cascade Drilling and Ryan Kroeker of the University of Guelph provided able assistance during field work at the Los Angeles site that was critical to fine tuning the small drills methodology for monitoring well clusters. Funding for development of this methodology and its application was provided by The Boeing Company, National Aeronautics Space Administration, United States Department of Energy, and Natural Science and Engineering Research Council of Canada Industrial Research Chair grant to Dr. B.L. Parker (IRC 363783-11).
Funding
The Boeing Company
National Aeronautics Space Administration
United States Department of Energy
Natural Science and Engineering Research Council of Canada. Grant Number: IRC 363783-11
Abstract:
Difficult access conditions have limited techniques for groundwater system characterization and monitoring in bedrock exposed landscapes. This condition is common in the mining industry and resulted in the development of lightweight portable drills. This paper describes how these drills were used at a contaminated site to understand the groundwater flow system by adapting piezometer designs, ensuring effective seals to obtain reliable hydraulic head, hydrochemistry, and contaminant concentrations. Two drilling machines were evaluated: the Shaw Portable Core Drill™ fits in a backpack and can advance continuously cored rock holes, nominal 51 millimeters (mm) diameter, to depths up to approximately 15 meters (m); and the larger Winkie Drill™ requires a two or more people to mobilize and can advance continuously cored holes, nominal 48 mm diameter, to depths of approximately 45 m. The resulting small diameter coreholes were accommodated in the design of each well using a seal created by injecting grout into a semipermeable fabric sleeve. This “fabric sleeve” serves as a means to contain the grout and ensures that the entire annulus above the screen is sealed without loss of grout into the formation, allowing the well to perform as a piezometer. To develop and demonstrate this methodology for groundwater monitoring in bedrock, the two drills were used in drainages located along the slopes of an elevated sandstone outcrop near Los Angeles, California. Unique insights into the groundwater flow system of this bedrock environment, which would otherwise be unattainable, were achieved. This methodology overcomes the accessibility limitations of conventional drilling methods that prevent installation of wells in remote and rugged mountainous terrains.