Geothermal Resource Group Inc. (GRG) PO Box 11898 , Palm Desert , California About Solutions industries services training Home Companies Geothermal Resource Group Inc. (GRG) Locations Geothermal Resource Group Inc. (GRG) Show or hide locations in map Headquarters Office locations Locations served Distributors Manufacturer Geothermal Resource Group Inc. (GRG) Headquarters PO Box 11898 Palm Desert 92255 California Phone/Fax Number Contact supplier Contact supplier Loading... Drop file here or browse Great, file uploaded. Change File Drop file here or browse Yes, please send to similar suppliers. SEND Cancel and close