This award-winning project at The Field Museum in Chicago, IL, involved the complete replacement of central heating and cooling systems within a two-level underground mechanical facility. The scope included installing new boilers, chillers, fire pumps, and air handling units, along with 48 ice storage tanks totaling 200,000 gallons, two 700-ton and two 750-ton chillers, and three 400 HP low-pressure steam boilers. Systems are monitored and controlled through a BACnet building automation system. Challenges included managing deep excavation with a high water table, restricted site access, and maintaining open parking facilities while preserving safe pedestrian flow for special events. The project was recognized with Midwest Construction’s “Best of 2003” Project of the Year in the power facility category.