Requirements of Soil Classification

1. Classification of soil and rock deposits: A competent person must classify each soil and rock deposit as Stable Rock, Type A, Type B, or Type C in accordance with the previously defined definitions.
2. Basis of classification: The results of at least one visual and at least one manual analysis must be the basis of the classification of the deposits. A competent person must conduct such analyses using tests described in the following slides; or in other recognized methods of soil classification and testing, such as those adopted by the America Society for Testing Materials;, or the U.S. Department of Agriculture textural classification system.
3. Visual and manual analyses: The visual and manual analyses, such as those previously mentioned, must be designed and conducted to provide sufficient quantitative and qualitative information as is necessary to identify properly the properties, factors, and conditions affecting the classification of the deposits.
4. Layered systems: In a layered system, the system must be classified in accordance with its weakest layer. However, each layer may be classified individually, where a more stable layer lies under a less stable layer.
5. Reclassification: If, after classifying a deposit, the properties, factors, or conditions affecting its classification change in any way, a competent person must reevaluate the changes. The deposit must be reclassified as necessary to reflect the changed circumstances.

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