noted that other positions suitable for mounting the hydraulic pump and motor may be utilized without departing from the scope of the invention transmissions such as the second transmission described above are available from suppliers such as omsi transmission of volciano italy and are disclosed in u s pat nos 5 826 460 and 6 393 944 the contents of which are incorporated herein by reference a first drive shaft 70 is connected to the output 54 of the first transmission 46 and the first input 58 of the second transmission 48 a second drive shaft 72 is coupled between the output shaft 60 of the second transmission 48 and the drive axle 50 of the truck referring to fig1 4 mounted on a rear portion 74 of the chassis is a holding tank 18 including a water tank portion 20 and a vacuum recovery tank portion or sump 22 in one embodiment the rear portion 24 of the holding tank is pivotally mounted on the truck chassis 14 and hydraulicly powered to tilt in the vertical plane to permit dumping of the contents of the vacuum recovery tank or sump the recovery tank 22 is operably connected to a vacuum pump 26 by a suitably sized conduit 28 the vacuum pump is preferably capable of drawing approximately 1100 cfm cubic feet per minute of air through the vacuum tank operably connected between the vacuum tank and the vacuum pump is a dust separator 30 the dust separator is constructed and arranged to prevent airborne particles drawn through the vacuum tank from being drawn through the vacuum pump and discharged into the atmosphere also mounted on the.