A container or pod is specially constructed for hauling proppant in support of oilfield hydraulic fracturing operations. Dimensions are provided that comport with common dimensions in use for transportation of intermodal containers, with the containers being sized so as not to require special permitting from a regulatory standpoint when two such containers are loaded on a single trailer. A method of filling the containers is also provided, which include inverting the container to fill from a bottom gate that also serves as the discharge opening when the filled container is rotated back into an upright position.