Coal Terminal Underground Leak Sealing

Problem

At a coal terminal facility in Newport News, Virginia, a several hundred foot vehicle access tunnel beneath an active railroad was facing severe water intrusion. This single-lane tunnel connected opposite sides of an equipment yard and had long suffered from persistent water infiltration at its joints. Over time, the issue worsened, resulting in standing water on the drive lane floor and visible leaks up to three feet along the tunnel walls.

During winter months, the problem escalated. Water would freeze on the tunnel floor, creating dangerous conditions that rendered the passage unusable for vehicles. Beneath the tunnel, a large void was also discovered, though the primary concern remained the extensive and chronic water intrusion and freeze thaw cycles.

Solution

A six-man JACKCRETE of Virginia crew was called in to deliver a targeted, efficient repair using polyurethane injection. The repair strategy involved a combination of single and dual-component polyurethane systems provided by NCFI Geotechnical:

• Terrathane 24-003 Dual-Component Polyurethane was used to fill the subsurface voids and reestablish soil connectivity.
• Terra-Lok 24-120 Single-Component Polyurethane was used to seal leaking joints and water pathways, especially overhead areas. The crew utilized a scissor lift for high point access during overhead injections.

Technicians worked methodically, injecting polyurethane along the full approach to the tunnel, down each wall, and into every visible leak path—including weep holes and known wet spots. In some areas, injection patterns followed a crisscross technique to thoroughly encapsulate the joints and maximize seal effectiveness.

As the polyurethane was injected, water was actively displaced from beneath the structure—what the crew referred to as “chasing the water.” Laser levels were used to monitor slab elevation throughout the process to ensure no unintended lift occurred. The structure itself had not settled; the objective was to seal the tunnel and reconnect it to surrounding soil without disruption to the slab.

Results

The entire tunnel was successfully sealed within just three days—a fraction of the time required by other repair methods under consideration. Despite the scope of the work, the JACKCRETE of Virginia crew was able to reopen the tunnel nightly to accommodate the facility’s around-the-clock operations.

Even more critically, the railroad above remained fully operational throughout the project, ensuring there was no disruption to the company’s essential logistics and coal terminal activity. The completed repair delivered a watertight tunnel that eliminated wintertime hazards, restored safe access, and showcased the speed, precision, and non-invasive benefits of polyurethane injection.

This project was recognized with an SPFA Industry Excellence Award, honoring the outstanding performance, efficiency, and innovation demonstrated by JACKCRETE of Virginia in addressing complex infrastructure challenges.