Aggregate Prequalification Program


The Aggregate Prequalification Program (APP) has been developed to provide contractors the ability to submit aggregate for quality assurance testing by Caltrans before the award of construction contracts. It is intended to reduce costs, delays, and additional liquidated damage payments to Caltrans associated with prequalification testing during the construction phase and allows Caltrans to achieve the goal of developing additional project delivery efficiencies as specified in SB 1.

The program is managed by Caltrans, Division of Engineering Service (DES), Materials Engineering and Testing Services (METS), Office of Central Laboratories (OCL), and the Aggregate Materials Testing Branch (AMTB).

Program Requirements

Requests for aggregate to be verified under the APP are addressed in the order in which a complete submittal has been received. The general process is identified below:

  1. Aggregate suppliers should e-mail the Aggregate Prequalification Request Form to the APP Administrator (
  2. A sampling date will be scheduled and a certified inspector from Caltrans will be present for sampling.
  3. Quality Control and Quality Assurance testing will be performed concurrently.
  4. Aggregate supplier must submit Quality Control test results onto the Data Interchange for Materials Engineering (DIME) database and e-mail the test reports to APP Administrator (
  5. After Quality Control and Quality Assurance testing are completed and test results are processed, the APP administrator will e-mail the supplier an acceptance notification valid for up to one year or a rejection notification.
  6. If accepted, the material will be placed on the Aggregate Prequalification Program List.

For full details and procedures on the submittal process, refer to the Authorization Criteria (PDF).

The Department retains the right to inspect, sample, and test aggregate source materials for additional verification at any time.

If you have any questions regarding the APP, please contact the APP Administrator at