The effect of hydration of mineral surfaces on sorption of organic compounds is well known and documented [1-3]. In the dry state, minerals have high sorption capacity for organic compounds. Upon hydration however, water molecules are preferentially adsorbed to mineral surfaces, reducing mineral sorption capacity for organic compounds substantially. In fact, because of this effect, natural organic matter is by far the most important sorbent for organic compounds in hydrated systems [4]. Yet surprisingly, and in contrast to the substantial literature concerning the mineral hydration effect, there is relatively little information related to the hydration effect on sorption of organic compounds by natural organic matter in soils and sediments.