Points depict aggregate sources that have been tested by the WSDOT State Materials Laboratory and are created from data in the Aggregate Sources Approval database (ASA). The Aggregate Sources Approval database identifies aggregate sources that have been tested by WSDOT, and have been assigned a county letter code with a sequential number for that county. It should be noted that there are sources that have been tested, but not classified with a county code, and are therefore not included in the database. Also, there are sources in the database that are not currently approved for use as materials on construction projects.