Western Alliance for Quality Transportation Construction (WAQTC)


The federal government requires any person performing quality assurance (QA)/quality control (QC) on state- or federally-funded transportation projects to be qualified. As a result, the Colorado Department of Transportation has implemented the WAQTC soils qualification program.

The purpose of this program is to meet the federal requirements and ensure that individuals responsible for the QA/QC aspects of highway transportation projects are qualified to perform soils test procedures in accordance with the applicable test methods and consistent test procedures. CDOT provides technicians with a qualification for inspection of soils and is included in the WAQTC qualification. 

During the COVID-19 pandemic, CDOT developed training videos to replace our in-person training program that was offered in previous years. These videos are provided as a resource to the industry to assist individuals for this certification (refer to Quick Links or visit Manual and Training Videos page here). In addition to the training videos and review of our manual, individuals coming in to certify are expected to have hands-on laboratory testing and field experience to be provided by their respective employer. When individuals come in to certify, they will immediately take the written exams without any overview and proceed directly into the laboratory for practical examinations.

Exam Overview & Schedule

This program is for engineering technicians and engineers responsible for sampling, testing and inspections for quality control of soils and aggregate. CDOT qualifies soils and embankment inspectors through WAQTC’s Embankment and Base and In-Place Density modules. This portion of the certification program involves written and performance exams on the WAQTC materials. In addition to the WAQTC qualification materials, CDOT desires to have our inspectors familiar with construction practices, geological conditions, testing procedures and construction specifications that are unique for Colorado.

The second portion of CDOT’s soils and embankment qualification process includes demonstrating a familiarity of the materials contained in in our Soils, Excavation, and Embankment Inspection manual by passing another written exam with questions related to the manual’s content.

This exam is open-book. Additional performance exams are also required to demonstrate ability and knowledge to complete other soil tests beyond that which are required to qualify for WAQTC Embankment and Base and In-Place Density certification.

Participants will have two attempts to pass both written exams. More detail on passing requirements can be found on the registration form.

Available course dates and cost are available on the WAQTC Exam Registration form.


Certification day will generally adhere to the following schedule:

  • 7:30 to 9:30 a.m. – Soil Inspection Written Exam
  • 9:30 to 10 a.m. – Break
  • 10 to 11 a.m. – WAQTC written exam
  • 11 a.m. to 4 p.m. – WAQTC and Soil Inspection practical exams (in lab)

All times are approximate, and may vary due to class participation.

Participants may elect to take only the Soils Inspector portion of the certification to become inspectors, however CDOT does require that any individual certifying for WAQTC Embankment and Base must also pass the Soils Inspection portion of the exam.

If a participant passes the written portion of the certification, but does not complete or pass the practical portion on the date of the exam, they may return to one future certification session and re-attempt the practical portion of the certification for a $80 charge. The individual will have up to 12 months to complete the practical portion retake. Retakes will be administered at the CDOT Materials Lab at 10:30 a.m. on the date of the exam. Fill out the Practical Exam Retake form to register your employee to retake the practical portion. You will be required to pay the registration fee at the time of enrollment by credit card or PayPal account. CDOT employees will not be required to pay at the time of enrollment.

You can reschedule your exam by filling out the Exam Reschedule Form. Please note that reschedules cannot be made within two business days of the course, and no refunds or credits will be made for no-shows. If your reschedule request is submitted online at least two business days prior to the exam date there will be a $45 charge. You will be required to pay the reschedule fee at the time of enrollment by credit card or PayPal account (CDOT Employees will not be required to pay at the time of enrollment).

Course cancellation is not available, but your company may substitute a current registration with an alternate participant at no additional charge. No notification of the substitution is necessary. You may simply send the alternate participant to the exam.

The exams in Denver are administered at the CDOT Materials Lab training room located at 4670 Holly Street in Denver, CO 80216-6408. Please note, exam participants must park in the lots to the east and west of the building (green areas). Vehicles parked on the north side of the building (red area) will be towed. The example below shows the correct parking location:

parking map

Once a year an exam is hosted in a CDOT facility in Durango or Grand Junction. Please contact us for more information about the location and times of these exams.