Test#6: Organic Impurities in Sand ( AASHTO T21/ASTM C40)

Organic impurities in sand (AASHTO T21/ASTM C40)
The method provides a good estimate of this type of organic matter , and when the soil contains only this type, it can also provide a good estimate of the total organic content.However the reagents used to react only very slightly with fresh plant materials such as wood , roots , and weed tops etc.., or with hydrocarbons , charcoal, lignite, coal and the organic remains in ancient sediments. If such materials are present, and the total organic matter is to be determined , then the "LOSS ON IGNITION" T 267 method must be used