Construction World July 2017

The paradigm shift “Owners of facilities should be more involved in the quality control and quality assurance of geosynthetic installations,” says geosynthetics expert, Nadia Minnaar of NGQ Consulting. “Who proposes that the best possible solution usually lies in employing a reliable independent 3 rd party company who can be their eyes and ears on the floor during the installation process.

She explains: “The differences between quality control and quality assurance is vast. Quality Assurance (QA) is a process orientated exercise that ensures the installation of geosynthetic material is in line with the SANS 10409 national standard, manufacturers installation instructions, industry best practice and project specifications. Quality Control (QC) by comparison is a product orientated exercise and therefore this includes all the testing that must be carried out by the installer to ensure the quality of the seaming installation is correct. Testing, is a product orientated process and thus falls in the QC domain. Testing for quality therefore is not assuring quality, it is controlling quality. In short: • Quality Assurance makes sure you are doing the right things, the right way. • Quality Control makes sure the results of what you've done are what you expected. Taking control “The independent 3 rd party company will therefore be responsible for the quality assurance of the geosynthetic installation and can also play a vital role in different stages of a project. For example, they can be involved when the project specification is compiled prior to tender stage, can be involved during tender stage to assess the quality assurance and quality control processes of the installer and to be a communication channel between all the parties during construction namely the owner, engineer, earthworks contractor and installer.

“It is common practice in other industries to make use of an independent 3rd party company but it is a new concept in the geosynthetic installation industry in South Africa and should become the norm for new installations to provide peace of mind to owners of facilities. “The independent 3 rd party company can serve different purposes during installation and act on behalf of the owner, the design engineer or the earthworks contractor since the installer is usually a subcontractor to the earthworks contractor,” says Nadia. Correct credentials NGQ Consulting is an independent 3rd party company who specialises in quality assurance. They have vast experience in the geosynthetic installation process with a state of the art software programme to co- capture QC information and provide the owner with a detailed project pack after completion. Nadia also recently completed a Liner Integrity Survey Assessment (LISA), Construction QA/QC for Geosynthetic Installation, Construction QA/QC for Compaction Clay Liners and Geosynthetic Certification Institute Inspector Certification Programme course presented by the Texas Research Institute and is now certified by the Geosynthetic Institute as a Quality Assurance Inspector for Geosynthetic Material and compacted clay liners. It is a known fact that when a leak occurs in the geosynthetic liner system it is usually due to other external factors and rarely as a result of poor workmanship of the

Capturing real-time data on site during the installation process. Nadia Minnaar of NGQ Consulting witnessing non-destructive testing of T-joints.

installer. This is why it is so critical to have an independant person on site to prevent material damage or report if damage has occurred. Also, to resolve the problem and take preventive actions to ensure damage is limited. “Yes, it is possible to build a facility with a zero leak rate – the secret to success is Quality Assurance,”concludes Nadia. 

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CONSTRUCTION WORLD JULY 2017