When taking a truck dump sample, what technique is used to ensure thorough mixing?

Using the technique of mixing from two directions perpendicular to each other when taking a truck dump sample is crucial for ensuring thorough mixing. This approach is effective because it helps to break up any potential segregation within the materials. Materials can often settle or layer based on weight or size, leading to a non-representative sample if not mixed properly.

By mixing from two perpendicular directions, you effectively combine the components from all areas of the dump, ensuring that different materials are evenly distributed throughout the sample. This method reduces the risk of bias that could occur if the mix were to be sampled from a single direction or from the same spot repeatedly, which may not capture the overall characteristics of the dumped material.

Employing mixed patterns also enhances the chances of collecting a sample that truly reflects the entirety of the load. Thus, this mixing technique is essential for obtaining reliable and representative results in aggregate sampling.