LES Rokeby Generating Station - General Excavating has built a reputation of excellence by specializing in unique below grade construction projects. While the Secondary Containment and Fuel Piping Improvement Project included a great deal of below grade work, it was the challenges above ground that required the most attention. Heavy rainfall, manufacturer delays, a unique pipe project, and a compressed schedule all played a part in pushing General Excavating and their subcontractors to find ways to overcome challenges on this Lincoln Electric System improvement project.

Following the design of Olsson Associates, work commenced with the enlargement of the containment cell. However, soon after the start of construction heavy rainfall left four to eight inches of water in the basin. Scrapers were unable to remove the mud and vegetation on their own so the muck was pushed into piles and loaded into the scrapers with an excavator. The LES Rokeby Generating Station located on the outskirts of Lincoln is the primary peaking power station for the Lincoln Electric System. EPA requirements dictated enlargement of the existing containment cell in the event of a rupture or failure of a 5 million gallon fuel oil storage tank. If General Excavating failed to meet the schedule deadlines, the power station would be unable to comply with EPA regulations and begin its operation of storing fuel oil.

Excavation of the secondary containment system at the LES Rokeby Generating Station.

Another main component of this project included abandoning an existing fuel oil line with flowable fill and installing new double-walled steel pipe protected by an outer layer of fiberglass. The new PermaAlert Ultra steel pipe required a great deal of labor for successful installation. The 40' pipe was first air tested, then welded together by Nifco Mechanical for installation of eighty-foot sections into the trench. The new joints were hand wrapped with fiberglass in the ditch. The pipe also possessed a leak detection system that would alert the owner in case of future leaks. The abandoned fuel oil supply pipe that criss-crossed the proposed construction route hampered excavation for the new fuel oil supply pipelines. Communications, other existing utilities, a chain link fence, asphalt parking lot, as well as a retaining wall stood in the way of construction of the new piping.

General Excavating was able to meet the demands of the job allowing the LES Rokeby Generating Station to continue its normal operation without disruptions. The success on this project was due in large part to the well-qualified subcontractors collaborating on this project. An EPA approved containment system as well as new double walled steel pipe with leak detection is now in place to address the needs of the LES Rokeby Generating Station and their capacity to provide power to the residents of Lincoln.