Record 42-Inch Bore Helps Connect LNG Terminal, Pipelines

Shared Risk, Cooperation Make Complicated Project Possible
April 2009 Vol. 64 No. 4

Grady Bell, project engineer for Laney Directional Drilling, said his company had completed a previous drill totaling 5,200 feet of 42 inch diameter pipe for an LNG project about 70 miles south of Houston. A 6,100 foot drill had been completed near Orange, TX, and had set the latest in a series of HDD records. “No one had ever attempted a drill of 6,700 feet of 42-inch pipe,” he observed.

From the onset, it was clear that everyone involved in the potentially record setting drill – Sempra Pipelines & Construction, LDD and Henkels & McCoy – would take on some shared risk and that a comprehensive risk analysis would be required. After his analysis, Paul Greenwell, LDD’s project manager, concluded that while the length of the drill was significant and the risks were reasonably high, the drill could be installed if all the risks could be identified and mitigated.

In addition, the need for large amounts of fresh water for the drilling process posed overwhelming challenges in this highly environmentally sensitive area. Although several avenues were explored to solve the water issue, the solution involved piping water approximately two miles from the Sempra LNG terminal to the drill site where it was stored in frac tanks.

Another significant challenge involved pulling the 3.5 million-pound pipe into the underground bore hole.

Environmental challenges included the project location in a protected wetlands area where flocks of Great Blue Heron nest. The area also is used by local duck and goose hunters

Despite the multiple challenges, the development team decided that the most efficient and cost effective way to proceed required a single drill crossing.

Because the earlier design that called for two separate drills had been finalized and approved by the U.S. Army Corps of Engineers, U.S. Fish & Wildlife, U.S. Environmental Protection Agency and the Federal Energy Regulatory Commission, the developer had to seek approval of the revised plan.