CEMEX Paiute Pit Reclamation

Q&D Construction successfully delivered an innovative and highly technical reclamation effort that required precision work in challenging underwater conditions. The project centered on constructing a new 70-foot-wide embankment extending 1,200 feet through water depths reaching 80 feet—an undertaking that demanded careful planning, specialized equipment, and constant verification to ensure accuracy below the surface.

To support the embankment, Q&D constructed an engineered 3:1 underwater fill slope designed to provide long-term stability. The slope extended as far as 240 feet from the embankment edge, with fill placement occurring in depths up to 80 feet. Despite the complexity of working in deep water with limited visibility, Q&D maintained the underwater slope within inches of the required plan grade—demonstrating exceptional quality control and field execution.

The project required placement of approximately 250,000 cubic yards of 6-inch minus crushed aggregate, carefully delivered and distributed to achieve the specified embankment footprint and engineered slope geometry.

Precision was achieved through a combination of advanced technology and practical ingenuity. Bathymetric survey equipment was used routinely to track underwater progress and confirm elevations. Between surveys, crews improvised real-time checks using a fish tape tied to a rock to verify interim grades. The future toe of slope was clearly established using empty one-gallon jugs painted orange, secured to rope lines and weighted with rocks—creating a simple but effective underwater layout system. In addition, an advanced fish finder was deployed to help crews “see” the evolving bottom conditions as material was placed.

To complete the work efficiently and accurately, Q&D utilized floating conveyors to place rock fill, guided by two GPS-equipped pontoon boats equipped with GPS systems to control alignment and material distribution. This combination of engineered planning, specialized marine construction methods, and creative field solutions allowed Q&D to deliver a stable embankment and precisely graded underwater slope that met design intent and exceeded expectations.