RAPID CITY - Putting together an arena to house an expansion hockey team is one thing, but construction of the skating surface is nearly as complex.

Construction crews are working on getting the floor completed this week, laying down cooling pipe before concrete is poured next week. But there have been many layers, materials and manhours involved to reach this point.

The ice floor began with a base coat that is, essentially, gravel, according to Brian Maliske, the general manager of the Rushmore Plaza Civic Center.

"On top of that is the heating pipe to create a layer between the sub-grade, which is that base coat, and the ice floor," Maliske said. "The ice floor freezes and they are deep enough that generally speaking the ground is not freezing. That can create some buckling problems."

Maliske said old ice arenas would have problems with their ice floors, because they were missing the heating pipe. The heating pipe keeps the ground below the ice from freezing, expanding and cracking the rink structure.

On top of the heating pipe is a layer of sand, followed by a four inches of insulation and the cooling pipe.

"To hold the cooling pipe in place, they have wire attachments," Maliske said. "Once all the pipe is down, they put another wire mesh on top of that pipe, that helps holds the cooling pipe in place so that when the cement is poured on top, the cooling pipes don't float or move."

Beginning next Wednesday, construction crews will begin topping off the floor with a layer of concrete. More than 270 cubic yards - or approximately 27 semi-truck loads - of concrete will complete the floor.

"That's a continuous, non-stop pour, the only continuous pour we have," Maliske said. "They can't stop, there can be no joints, no expansion or cracks in (the concrete)."

Steve Montgomery, the sales and marketing director for the Rushmore Plaza Civic Center said protecting the ice, once it has been created, will be equally painstaking.

The ice temperature must remain between 16 to 22 degrees, depending on whether the event is hockey, ice skating, or motorcycle racing. But the floor covering must be thick enough and insulated enough so that foot traffic above the ice enjoys a temperature of 64 degrees. To accomplish that, panels of a non-porous plastic and fiberglass composite material fit together similar to a jigsaw puzzle over the entire surface of the ice.

"The floor coverings we put on top will go between the ice and whatever goes on top of that," Montgomery said. "Sometimes it will be chairs for a concert, sometimes it will be putting down a wood basketball floor on top of the ice cover. Sometimes it could be a rodeo, it could be dirt … anything we want."