A system and a method for removing a coating from a substrate. The system provides a compressed air source, a heated water source, a particulate cleaning medium source, and a mixing valve including an air input, a water input, and a particulate cleaning medium input. The inputs are positioned on the valve so that the water input is positioned downstream of the compressed air input, and the particulate cleaning medium input is positioned downstream of both the compressed air and water inputs. The method of mixing the air, water, and particulate cleaning medium provides a coating removal mixture having a volumetric ratio of air to water of at least 100:1 and a volumetric ratio of air to particulate cleaning medium of at least 70:1.