The hot mix is waiting in the silo and the trucks are starting to roll. Each load is controlled by the hot plant operator to guarantee proper mix design and weight for each truck. At this point, the temperature of the mix is 240° - 320° to allow for cooling enroute to the job.

The heart of this operation is the paving machine and crew. A paving crew consists of the paver operator, two screed operators, the broom/tack truck and roller operators. A great deal of skill is required by the crew and the truck drivers to complete this operation successfully. When a truck arrives from the plant with the hot mix, it is backed up to the front of the paver. As the load is dumped into the paver hopper, both the truck and the paver move forward in unison. The paver operator directs the trucker with hand signals. When one load is emptied into the paver, the empty truck pulls away to head for the plant and pick up another load, while the next full truck backs into position. So there is a constant rotation of trucks at the paving site. Depending upon the distance from the hot plant, it can require up to 20 trucks to keep the paver operating. A smooth flow of trucks is critical, because the mix must be laid down before its temperature drops below 240°, or it cannot be properly spread and compacted.

Once in the machine, the mix is conveyed into augers. The augers, in turn, feed it into the screed, which spreads it out and lays it onto the roadway in a smooth even layer. The screed operators ride the back of the machine and keep the mix to the proper depth while it is being laid down. The depth varies minutely because of irregularities in the roadbase material. Asphalt is put down in several layers, called "lifts." A lift is normally 1-3 inches thick. The width of each pass, or "mat," can vary from 8" to 18", depending on the paver used and the job being done.

When part of the mat is laid, the roller operator compacts the asphalt while it is still hot, to provide a smooth hard surface as it cools.

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