Along the Tier A street frontage of a ground floor level, for any blank walls, at least 70 percent of the surface area of such blank wall shall be mitigated with wall treatment, in the form of permitted signs, subject to the provisions of Section 32-60, murals or other visual artwork, or living plant material. Any portion of a mural or other artwork that incorporates addresses, text or logos related to the building or tenants therein, shall be considered a sign.