Reclamation Information Sharing Environment (RISE)

Reclamation has used natural pozzolans for large dams in the past. Trends in the market made fly ash a more preferable choice as a supplementary cementitious materials for decades. As the future supply of fly ash becomes less predictable, concrete producers are more interested in other pozzolans including natural pozzolans. This report summarized Reclamation’s history with using natural pozzolans and proposes sites to extract cores to assess the long-term durability of concrete made with calcined shales.