Crux was contracted to provide drilling and geophysical services to locate potential pipeline alignments, provide information for the tunnel system construction, and develop a foundation design for the diffuser. Both land-based and offshore exploration drilling were required for the 14-mile alignment.
The offshore exploration program consisted of drilling shallow borings along the proposed diffuser alignment in water depths exceeding 250 feet. Crux utilized a custom barge system for accessing and working in these water depths. The land-based exploration program consisted of drilling HQ3 borings to depths of 1,000 feet in the River Mountains, and several borings along the remaining alignment to depths of between 100 and 500 feet. Access to land-based borings required truck-mounted, track-mounted and helicopter-portable equipment.
Logistics and access to boring locations, in combination with poor geologic conditions, created a challenging drilling environment. Crux was required to provide a drilling program that minimized environmental impact, which necessitated drill fluids and spoils containment, as well as specialty fueling systems. Minimal environmental impact also required collaboration with the Bureau of Land Management and the U.S. National Park Service to develop Best Management Practices for land-based and offshore drilling operations.