October 7, 2016 Meeting Landfill Liner Regulations with Conductive Backed Geomembranes by Doyin Adesokan B.Eng Msc. Technical Manager - Solmax

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1 Covering the world. Protecting the earth. October 7, 2016 Meeting Landfill Liner Regulations with Conductive Backed Geomembranes by Doyin Adesokan B.Eng Msc. Technical Manager - Solmax

2 Outline Quote What are conductive backed GMBs Types of damages to GMBs Some stats on leakage sources Some definitions Preventing leaks/leakage Electric leak locations (ELL) surveys Conductive liners for ELL surveys Recap and conclusion 2

3 But we have learned over the years that while non-leaking facilities can apparently be built, damage happens and should be considered unavoidable Ian Peggs P.E. Ph.D Geomembrane Liner Action Leakage Rates: What is Practical and What is Not? 3

tool for finding damages/holes Conductivity is from carbon

4 What are conductive backed GMBs? 3 mil Co-extruded Electrically Conductive Skin An effective tool for finding damages/holes Conductivity is from carbon black The conductivity depends on the structure, particle size and loading level of the carbon black

5 Types of damages to Geomembranes Fully penetrating (GMBs) pinholes, holes, tears, cracks Partially penetrating scratches, cuts, scuffs Latent wrinkles, localized strains, poor quality welds

6 Some statistics on sources of leaks in Installation 24% of holes GMBs Poor quality welds = 61% Melting or overheating = 18% Stone penetration = 17% Cuts = 4% Noski et al. (1996) R&D report by the Environment Agency

8 Holes from weld defects

9 Opening from a latent defect a poor quality weld

10 Some statistics on sources of leaks in GMBs Placement of cover material (backfilling) 73% of holes Stone puncture = 68% Heavy equipment damage = 16% Noski et al. (1996) R&D report by the Environment Agency

13 Some definitions A Leak an opening that permits the ingress or escape of something Leakage an amount that is lost through a leak. Leak size the size of a leak expressed as a surface area or as a diameter (e.g. a 1 cm2 leak, an in2 leak, a 2 mm diameter leak, a 0.25 in diameter leak). Leakage rate (Q) leakage quantity per time, expressed as a volume /unit of time e.g. m3/s, l/d, gallons/day Unitized leakage rate (q) = Q/A (leakage rate per unit area of liner); Giroud and Bonaparte 1989: Leakage through Liners Constructed with Geomembranes-Part I. Geomembrane Liners

14 Preventing leaks/leakage Careful installation/backfilling Rigorous CQA Design Single vs. double liner systems with allowable leakage rates (ALR) 500 gal/acre-day in New York and a number of other states Material compatibility Leak Location Surveys How Much Does my Landfill Leak? Beck, 2014

15 Preventing leaks - Leak location Weld testing part of CQA Air channel Vacuum box Geomembrane panel testing Electric Leak Location (ELL) Acoustic methods Infrared Thermography (IRT) 15

16 Electric Leak Location (ELL) surveys Uncovered geomembrane tests Water puddle/water lance Arc testing Spark testing conductive backed geomembranes Covered geomembrane tests Dipole testing water or earth covered 16

17 Electric Leak Location (ELL) surveys Uncovered (bare) GMB ELL survey Water puddle/water lance Water puddle/ water lance

18 Electric Leak Location (ELL) surveys Uncovered (bare) GMB ELL survey Arc testing 18

19 Electric Leak Location (ELL) surveys Uncovered (bare) GMB ELL survey Spark testing Conductive backed GMBs - ASTM D

20 Spark testing conductive backed GMBs for leaks Grounding Pad Test Wand

1 mm diameter - pinholes Locates holes on wrinkles Effective on slopes Subgrade

21 Benefits of spark testing - conductive geomembranes ASTM D7240 Effective hole detection as small as 0.1 mm diameter - pinholes Locates holes on wrinkles Effective on slopes Subgrade conductivity not required The grounding electrode is close to the operator no need for long wires connected to the ground 10 to times more flow!!! 21

22 Covered GMB ELL survey dipole testing ASTM D7007 Aggregate covered Water covered

23 Soil covered dipole survey -ASTM D7007

24 Benefits of dipole testing with conductive GMBs In a double lined system the leak detection layer will be flooded unless a conductive backing is used *Conductive GMBs preferable* 24 Retrieved from an internet portal

25 Success rate of ELLs with conductive backed GMBs?

26 The best way to deal with a problem is to avoid creating it in the first place

27 Recap and conclusion 1 of 4 Damages and leaks in GMBs should be prepared for This preparation should involve careful material selection especially those that have inherent properties for leak location Good designs Effective leak location methods

28 Recap and conclusion 2 of 4 ELLs on bare GMBs after installation & on covered GMBs following backfilling are essential for finding leaks

29 Recap and conclusion 3 of 4 A conductive backed GMB makes ELL surveys more effective and it overcomes the limitations of the other ELL methods Retrieved from an internet portal

30 Recap and conclusion 4 of 4 Good to have the conductive GMB in white: For CQA & damage location black on white For welding white in the seam Welding conductive GMs core to core Source: Scheirs,

31 Contact information: Doyin Adesokan B.Eng Msc. Tel: Thank you 31

Leak Location Geosynthetic Materials in Base Liner Systems. NY Federation SWANA. May, 2014

Leak Location Geosynthetic Materials in Base Liner Systems NY Federation SWANA May, 2014 Different ELI Surveys A. Covered Electrical Liner Integrity (ELI) Survey Dipole Method Suitable for water or soil