You are the ONLY person on the road. You drive up on a diesel truck on its side with smoke bellowing from underneath it laying against a large hill of sand. You see a DOT placard with the number of 1403 on the rear and side of the truck. The fire is not too bad and you have a class A fire extinguisher in your car with you that you can easily put the fire out with. The driver is smoking and not saying anything but to PLEASE save his truck. There is a ditch with water about 4 feet deep and he has 5 gallon buckets on the truck which is perfect for putting out a fire. There is a grey gravel like substance on the ground and catches fire as well. The fires are not too large for a one person extinguishing. What do you do?