Arkansas Horizontal Dual-Phase Extraction Wells
DTD has recently completed a small scale project near Little Rock, AR. Plans for bettering the subsurface conditions included two dual phase extraction (DPE) wells targeting a shallow plume beneath a busy four lane highway. Unable to address this contamination with vertical technology, DTD was contracted to drill these wells horizontally, entering the ground from a local restaurant parking lot.
Access to the property across the road was restricted so the wells were completed blind, extending beneath the highway and terminated below the ground surface. The north and south wells were 3-inch diameter and extended 109′ and 180′, respectively, from the entry points.This project was completed with one of our smaller sized drill rigs (Vermeer 24x40a) and despite being on schedule and under budget, a few challenges were encountered.
Project location (“Red” lines indicate bore paths)
As with most road crossings in suburban environments, multiple utilities existed in the DOT right-of-way. Also, moderate to heavy vehicle traffic in the adjacent businesses and highways were present during the project. Both of these issues were addressed prior to mobilization, which allowed for efficient drilling operations once we were in the field. All utilities along the bore path were marked and exposed prior to mobilization. This was crucial to the project timeline as we were able to adjust the entry point quickly and begin drilling by visually observing our tooling passing the utilities in question along the entry curve of the bore path. Tackling the heavy traffic present in the area was an ongoing task of barricading/securing the jobsite and carefully locating the bore path after proper DOT restrictions (signs, flagging, etc.) were completed. While careful planning before mobilization did not eliminate these issues, they challenges were addressed safely and did not create any unexpected delays in drilling operations.