Where should sampling occur when pulling a tank?

The correct approach for sampling when pulling a tank is to perform the sampling within 6 inches of each end and 6 to 12 inches from the bottom. This method is effective because it allows for the collection of a representative sample of the contents of the tank, capturing the potential variations in the fuel or oil that may have settled at different levels.

Sampling within this specified range helps to ensure that both the heavier sediments that may accumulate at the bottom and any variations in the quality of the material are accurately assessed. By including samples from both ends of the tank, this method also accounts for any uneven distribution that may exist within the tank due to factors like temperature gradients, tank shape, and how the tank was last filled.

In contrast, sampling at the midpoint of the tank or throughout the entire height might miss variations that occur closer to the ends or at the bottom, where contaminants could settle. Sampling only at the bottom would not provide a complete representation of the tank's contents, as it neglects possible stratification within the tank. Therefore, choosing the specified range ensures a more thorough understanding of the tank's contents and clarity in identifying any issues.