Easement Details

We are the civil engineers for a development project at 715 North Czech Hall Rd in Yukon, OK. The parcel we are working on contains an easement granted to AT&T which states that "no structure shall be erected or permitted on said strip." 

I am wondering what the definition of 'structure' is in this context. To the south of our parcel, it seems that there is a parking lot constructed over the easement. Our current site plan calls for something similar. Would pavement be considered a structure with regards to the easement? Please let me know who I should contact to obtain this information.