From Gabriel Barkay and Zachi Dvira, Temple Mount Sifting Project

The Temple Mount Sifting Project arose out of the illegal staircase construction by the Islamic Waqf, who, in order to make space for new stairs, dumped soil from the Temple Mount into the Kidron Valley. The soil became the basis for the Sifting Project. While dry-sifting was fairly common prior to this, the Sifting Project’s success has led many to adopt the practice of wet-sifting. Every bucket of dirt is first dry-sifted and then a copious amount of water is added to the sample for the wet-sifting process. The benefit of wet-sifting is that organic material will float to the top, and overlooked artifacts are more easily identified, as the water removes dirt that was clinging to the small finds.