Aggregate Quality Control/Quality Assurance Program
Standard Operating Procedure No. 1 (SOP 1) "Monitoring the Quality of Coarse and Fine Aggregates" is the document that governs how Georgia's Aggregate Quality Assurance Program is administered. it clearly defines what constitutes certifiable aggregates and defines the Department's policies for accepting delivered materials. Qualified Products Lists (QPL) 1 and 2 lists all potential sources of aggregate and specifies the acceptance criteria for aggregate delivered from them. A Basics of Aggregate Certification Guide is available.
Based upon internal Quality Assurance Programs, most sources listed on the QPL are allowed to certify the quality of their aggregates. Certified aggregates are allowed to be delivered to the project and incorporated directly into the work without any notification to or pre-testing by the Department being required. Acceptance samples of certified aggregates are taken by the Department at a greatly reduced frequency as opposed to acceptance samples of no-certified materials. For example, non-certified graded aggregate is subjected to project acceptance sampling at a rate of one sample per 1500 tons whereas certified graded aggregate is sampled at a rate of one sample per 20,000 tons of delivered materials.
The approved status of a source is to certify aggregates is contingent upon their meeting the specifications, strict adherence to source specific Quality Assurance Programs and compliance with the policies of SOP 1. The Quality Assurance Programs are prepared by the Department and tailored to the specific source depending upon the nature of the deposit and plant capabilities. The sources are visited by Aggregate Control Engineers (9 statewide) on a random but routine basis. During these visits, compliance to the Quality Assurance Programs, the specifications, and SOP I are monitored by inspecting the pit, stockpiles, production, shipping, reviewing test data, and sampling and testing material at the site as needed.
The quality of materials is also monitored by the continual review of test results of samples that are submitted on a monthly basis to the Central DOT Laboratory by the Aggregate Control Engineer. These samples are subjected to a full battery of tests such as Abrasion, Soundness, and Specific Gravity; tests that most producers are not required to perform. The quality of the producer's certification data is also monitored by an Aggregate Rating System that is statistically determines when a producer's data is too marginal to be accepted for certification.
Aggregates from sources that are not approved to certify their materials are approved on a stockpile basis only. Approval to ship a particular stockpile must be granted by a Departmental Representative prior to shipment. Materials supplied from the approved stockpile are also subjected to full project control acceptance testing after delivery and prior to use at the project or plant site.
A primary and back up Quality Control technician is certified at each aggregate source. When an aggregate source requests to be added to QPL 1 or 2, a study guide is given to the Quality Control technician to study and use as reference material. When the technician is ready to take the written test, he or she contacts the Pit and Quarry Branch and requests to take the test. The technician is then scheduled for the test, which is offered on the first and last Thursday of the month. Upon passing the written test, the Area Aggregate Engineer visits the source to observe the technician perform the required tests. If the technician is able to perform the tests properly and if the laboratory meets our requirements, the technician and the lab are certified, and the technician is issued a certification card.The quality control technician retains his or her certification for three years, but the source laboratories are recertified annually. To renew his or her certification, a technician must either retake and pass the written examination or complete 18 hours of approved training in addition to retaking and passing the laboratory proficiency examination. Details of the recertification program may be found in our Standard Operating Procedures – 1 (SOP – 1).
This program is designed to train and certify technicians to properly sample and test common highway construction materials. It is important for employers and industry personnel to understand that these certifications are on a very basic level and do not imply that a technician is qualified to do anything more than sample and/or test materials. That is to say, they are certified to provide data to industry experts who interpret the data and make decisions based on their level of expertise.
Notice: This page and the information linked to it is for informational purposes only at this time. This certification program is still under development and information will be posted as it becomes available.