LINER WELDING TECHNICIAN CERTIFICATION: should this be a requirement?

Geosynthetic materials play a vital role in any well-engineered landfill site. Charl Cilliers, president of GIGSA (Geosynthetics Interest Group of South Africa), covers the importance of employing certified welding technicians in the management of risk on liner installation projects.

The role and use of geosynthetic materials in landfill construction is well known and documented. Landfill liner systems are a critical element of the designs of new landfills. This is due to their essential function in protecting soil and groundwater by isolating landfill contents from the environment and draining leachate to collection and treatment facilities.

In a panel discussion hosted by GIGSA during the IWMSA’s Landfill and Waste Treatment 2021 Virtual Seminar, group members unpacked the importance of correct installation and the possibility of introducing a liner certification programme in South Africa.

This certification would play an important role in providing a higher level of construction quality management.

National standards

The National Norms and Standards (GNR 636 (23 August 2013): National Norms and Standards for Disposal of Waste to Landfill) prescribe the barrier systems required for various classes of landfill – in many of the classes, geosynthetics are prescribed. The standards also prescribe the level of detail required in design, which is then submitted to authorities for approval.

The requirements also include submitting a construction quality assurance (CQA) plan, which is widely recognised as a critically important factor in overall quality management for waste containment facilities of all types. This includes geosynthetic materials.

CQA is a system of activities that provides the owner and permitting agency assurances that the facility was constructed as specified in the design. It also includes inspections, verifications, audits and evaluations of the materials and workmanship necessary to

Importance of proper installation

Cilliers asserted that the correct installation of geosynthetics, as per CQA plans and the national standards, is essential to ensure that engineered landfill sites perform effectively.

“Correct installation is vital and, in many instances, millions are spent on the procurement of correct material, only to fail during the installation process.”

Having certified lining contractors and welding technicians would mitigate against the incorrect installation of geomembrane barriers. That is one of the reasons why implementing a liner certification programme would be advantageous for the industry. Cilliers stated that certification would help to determine whether companies or individual liner installers have an industry-determined base level of experience to complete a particular project.

“The certification will provide assurance that the on-site liner installer and their team have the necessary skillset. However, if they don’t have that certification, you’d have to base their competency on the CVs submitted,” said Cilliers.

This is one of the main motivations behind introducing certification into the South African liner industry – providing assurance that liner installers have the experience to deliver a quality end-product.

Certification

Currently, South Africa does not have its own certification body, meaning that the certification of liner installers would take place through the International Association of Geosynthetics Installers (IAGI) body. Founded in 1995, IAGI is the professional association representing geosynthetic material installers and their industry partners.

IAGI’s Certified Welding Technician (CWT) programme aims to recognise the knowledge, experience and skill of those technicians who hold the certification. Project teams benefit from IAGI’s CWT programme because certification verifies that the job’s welding technicians have experience in geomembrane welding and meet the expected industry skill levels for different types of geomembranes.

All the information needed to conduct the CWT exams is contained in the Proctor Manual for every specific material type. The six-step certification programme includes:

1. Determining whether the welder meets the minimum experience level for the type of geomembrane being tested.

2. An experienced proctor is needed to coordinate and oversee the exam process.

3. Setting the date, ordering the exams for the material type, and choosing the language of the exams.

4. Assembly of the geomembranes needed for certification exam.

5. Test preparation.

6. Taking the exam.

The certification by IAGI is renewable on a fiveyear basis.

An established industry contractor asserts that the IAGI welding technician certification is just the first step in the right direction.

As argued during the IWMSA discussion, “More important is the certification or accreditation of companies. Certifying welding technicians is crucial to ensuring the people on the ground know what they are doing but when it comes to critical applications you need more.”

The following was recommended:

• Companies must be responsibly managed and employ qualified individuals throughout their organisation who can deal with matters in a competent way.

• The company needs to have the financial ability to provide bonds and insurance.

• References from engineers, clients and manufacturers are needed to prove that business is conducted in a professional and competent manner.

Drawbacks

Cilliers stated that although GIGSA recognises the many benefits associated with introducing certification, there are some disadvantages that would require consideration to insure fairness.

“Certifying an entire team can be a costly exercise for smaller companies. One option is to implement a tiered approach, where higherspecification facilities require more stringent certification measures compared to lowerspecification ones.

“There is also a perceived need for ongoing monitoring of the technician’s development between renewals to ensure that the individual can still perform at a base level,” said Cilliers.

All-inclusive approach

GIGSA believes an equally important aspect would be to insure that “we do not exclude any companies from operating within the liner industry, through this certification.” Opportunity needs to be maintained to ensure that the smaller companies will be given the chance to develop skills to grow and tender on bigger projects.

Cilliers concluded that the discussion on this topic was only the start and conversations like these are essential for industry development. GIGSA is convening a working group to develop this topic further and all interested parties are invited to contact GIGSA through their website. Organisations like GIGSA aim to educate the industry and promote the appropriate use of geosynthetic technology throughout South Africa.