Burns & McDonnell acted as EPC contractor for this project. Included in the EPC scope was right-of-way (ROW) acquisition; procurement of all structures, assemblies, conductor, substation steel, equipment and protection; detailed design; construction management; construction; permitting; and overall management.
Burns & McDonnell subcontracted ROW acquisition, construction, surveying, geotechnical investigation, and testing services. All other services are self-performed, including transmission and substation design, permitting, construction management, procurement, scheduling and cost control.
The 345-kV transmission line includes single circuit and double circuit configurations. The structures are monopole on drilled pier foundations. The double circuit sections include 161-, 115- and 69-kV lines requiring close coordination with other area utilities.
The 115-kV transmission line includes single and double circuit configurations with sections of single and double circuit underbuild. Double circuit sections include 24-, 69- and 115-kV construction. Underbuild is 34.5-kV consisting of local wind farm collection circuits.
The 345-kV line originates east of Sioux Falls, S.D., at Split Rock Substation and is generally routed east paralleling I-90 to Lakefield Junction in Minnesota. The 115-kV line originates near Worthington at a new substation and is routed northeast to an existing substation, Chanarambie, west of Lake Wilson City.
Near our field office in Worthington, Minn., is the larger of the two substations, Nobles Substation, a 345/115-kV substation with a 672MVA autotransformer. The Split Rock and Lakefield Junction lines connect at Nobles. The 115-kV line leaves to the north to a new substation, Fenton.
The Fenton Substation is roughly halfway between Nobles and Chanarambie substations. Like Chanarambie, Fenton Substation is a wind farm collector station. The substation consists of two 170 MVA 115/34.5-kV transformers.
Chanarambie Substation was expanded to accept the new 115-kV transmission line. Split Rock Substation will be expanded to accept the new 345-kV transmission line.
Burns & McDonnell employed a sizable field staff for the project, including a site manager, multiple discipline superintendents, a safety lead, a schedule controller and other administrative staff.