OPTIMIZING HORIZONTAL DRILLING OPERATIONS WITH ELECTRICAL IMAGING

Horizontal directional drilling (HDD) operations are impacted by at least three subsurface hazards, including: deep mines; fractured or faulted rock; and incompetent rock. The tri-state area of Ohio, West Virginia and Pennsylvania contain all three HDD hazards. Electrical imaging proved to be the most successful and least expensive method to predict subsurface conditions.

Drilling through mine voids in Ohio created an environmental hazard when HDD drilling fluid discharged to a nearby strip-mine lake. Three-dimensional mapping from electrical imaging (EI) profiles provided an alternate route for the HDD to prevent the continued loss of drilling fluid.

Fractured or poorly indurated rock poses a challenge to HDD operations, primarily through the loss of fluid. An 11 mile HDD alignment in eastern West Virginia crossed 3 creeks with questionable subsurface conditions. EI provided directions for the HDD alignment that minimized the potential to encountered fractured and poorly consolidated rock.

Traversing hilly areas with the possibility of encountering a deep-mine is a common issue in western Pennsylvania. EI profiles provided a method to detect and map features related to deep-mining within a known area of historic mining operations.