Craig, Colorado

NOx Reduction Subsurface Project

Client / Owner

Tri-State Generation and Transmission Association, Inc.

Architect / Engineer

Black & Veatch




Graycor Industrial

Project Scope

For this civil site work and underground project, Graycor Industrial’s team provided the foundations and necessary utility modifications/relocations to enable the SCR and ammonia unloading facility to be installed. This work encompassed the installation of more than 400 auger cast piles, all of the necessary excavation and backfill, installation of approximately 800 feet of duct bank and ammonia piping, while placing more than 2,800 cubic yards of reinforced concrete foundations with more than 300 embedments. In addition, this work included installing 2,400 linear feet of stainless steel underground piping,

Graycor’s team completed the project ahead of the original schedule despite the scope doubling due to revisions of the original quantities.

The project was also successful in terms of safety due to the team achieving no recordables throughout the project’s duration.

Scope of Project:

404 APG piles, 39’ long x 18” diameter
2,800 CY reinforced concrete foundations
2400 LF stainless steel piping, 1-1/2” diameter
800 feet of duct banks
300 anchor bolts