The approach used to calculate the SSS for direct contact was to use the Adult Lead Model recommended by the EPA. The PADEP used the same model to develop an updated non-residential lead direct contact MSC that reflects the current state of the science for lead. If the PADEP changes PADEP’s assumptions related to lead, such as permissible blood lead levels, Evergreen will update the SSS accordingly. The SSS for lead utilized the updated Adult Lead Model and exposure assumptions recommended by the USEPA and the PADEP. If the PADEP changes their assumptions related to lead, such as permissible blood lead levels, Evergreen will update the SSS accordingly.