Provided is a chemical injection system for connection to a chemical tank and a process line. The system includes a pump box configured to attach to the tank, the pump box including a body defining an interior, a pump assembly disposed within the interior of the body of the pump box, and an injection assembly configured to be fluidly coupled to the pump box. The injection assembly includes an injection lance having a flange and a stem, a first seal abutting a first side of the flange of the injection lance, and a second seal abutting a second side of the flange of the injection lance.