A remote mine seal spray nozzle assembly is provided that includes a rotatable nozzle body attached to a down shaft, multiple string casing. The nozzle body receives interchangeable nozzles coactively seated in a multiport manifold of the nozzle body casing. The nozzle defines a downstream spray outlet that projects a first mix formed of a cementitious grout including a water reducer and a plasticizer. The projected first mix is atomized with a second mix formed of pressurized air and a temperature optimized accelerant. An atomized mine seal mix is thereby created and projected from the downstream spray outlet to form a rapidly hardened mine seal from the accumulated mix projected from the nozzle. The multiport manifold seat establishes an upward directed spray throw axis whereby the projected mine seal mix is projected about a substantially upward arc to optimize the sealing capability of the remote mine seal.