NGQ Consulting

Passionate about quality

Providing mining, construction and engineering customers with the confidence that their geosynthetic projects will stand up to regulations, industry standards and the pressures of the environment.

WHO WE ARE AND WHAT WE DO NGQ Consulting (Pty) Ltd (NGQ) provides independent atsource and on-site construction quality assurance and control service for geomembranes. Our CQA/CQC services are an essential element in ensuring compliant geomembrane installations and cover receiving, installation and remedial work.

The NGQ team is well versed in verifying geomembrane installation procedures and in certifying the safety, purity and integrity of installed materials. We make sure that all project-specific requirements, CQA plan requirements, industry best practices and internal specifications are met. We also ensure compliance with current national and international standards as well as with legal and regulatory requirements. Our involvement includes lining-material compliance, lining-surface preparation, and installation methods. It also entails using an electronic cloud based quality assurance program with a project specific dashboard for daily quality control testing and live monitoring of the installation process.

NGQ uses a state of the art cloud based quality assurance program designed in compliance with SANS 10409. Besides the program’s live monitoring capability and numerous verification options each tab carries the necessary critical data required to control and trace every step of the installation, from the receiving of material to final hand-over. It also facilitates task-exact checklists and daily sign-offs by the engineer, client representative or independent CQA. The system ensures that work is completed on a daily basis, and keeps the key role players up to date with a project’s progress at all times, from anywhere in the world.

NGQ maintains its technical expertise by placing strong emphasis on continuing education and training in order to ensure that our professional expertise remains current. Our internal QA/QC training programs meet and exceed multiple industries’ standards for qualification and certifications. Our inspector has been accredited by the Geosynthetic Research Institute (GRI) as a certified welder and was trained by the Texas Research Institute (TRI) as a liner integrity survey and assessment (LISA) operator. She is also an active member of the Geosynthetic Interest Group South Africa and the International Association for Geosynthetic Installers. (IAGI).

LINER INTEGRITY SURVEYS AND ASSESSMENTS (LISA) NGQ Consulting (Pty) Ltd (NGQ) provides independent liner

art leak-detection methodology Increasingly specified by

integrity surveys and assessments for HDPE/LLDPE geomem-

environmental regulations, they are also applied voluntarily by

brane installation at source. This service is an essential ele-

many site owners as responsible environmental stewards and

ment that helps ensure leak-free geomembranes in different

to forestall any future liability.

geomembrane containment structures which are typically used for the large-scale containment of liquid and/or liquid or

Liner Integrity Survey and Assessments are used to locate leaks

solid waste.

in installed geomembrane containment structures such as: • Landfills

Electrical liner integrity surveys and assessments Electrical liner integrity surveys and assessments, also known as leak-location surveys or electrical-leak detection are a post-installation quality-control method for detecting leaks in geomembranes. Locating leaks in installed geomembranes

• Reservoirs • Liquid Impoundments • Heap Leach Pads • Leachate Ponds

is imperative for the long-term protection of groundwater

• Wastewater Lagoons

and the maintenance of water resources and these electrical

• Lined Tanks

survey techniques are widely embraced as the state-of-the-

• Secondary Containment for Fuel Storage

Survey methods in use: Liner Integrity Surveys and Assessments can be performed on bare geomembranes as well as those covered with earth, water or wastewater.

Electrical leak detection (ELD) feeds electricity from the top of the geomembrane into the subgrade below. Since geomembranes are electrically isolative, this method is able to detect any holes in those places where the current penetrates the geomembrane. The current is tracked differently depending on whether the geomembrane is covered or exposed.

When testing bare geomembranes, water is sprayed onto the geomembrane to carry the applied current. Alternatively, a high voltage is introduced above the geomembrane to create an electrical arc where leaks exist.

The following ASTM methods have been developed for Liner Integrity Survey and Assessments: 1. Guidance for Method Selection:

ASTM D6747 Standard guide for selection of techniques

for electrical leak location of leaks in geomembranes

2. Bare Geomembrane:

ASTM D7002 Standard practice for leak location on

exposed geomembranes using the water puddle system.

Also applicable to water lance.

ASTM D7703 Standard practice for electrical leak location

on exposed geomembranes using the water lance system.

ASTM D7240 Standard practice for leak location using

geomembranes with an insulating layer in intimate contact

with a conductive layer via electrical capacitance technique

(conductive geomembrane spark test).

ASTM D7953 Standard practice for electrical leak location

on exposed geomembranes using the arc testing method.

3. Covered Geomembrane:

ASTM D7007 Standard practice for electrical methods

for locating leaks in geomembranes covered with water

or earthen materials.

CONTACT DETAILS: NADIA MINNAAR CELL: 079 875 5691 | EMAIL: nadia@ngqconsult.com POSTAL ADDRESS: Postnet 182, Private bag X504, Sinoville, 0129 PHYSICAL ADDRESS: Minnaarsplaas #4, Cullinan, 0035