Liner Construction Testing Guidance Overview Ruben Meza Jr

Liner Construction & Testing Guidance Overview Ruben Meza, Jr. , P. E. Waste Permits Division Municipal Solid Waste Permits Section 2017: TCEQ Environmental Trade Fair

Agenda • Summary of Revised Guidance Document • Liner Design – Basic Requirements • Compacted Clay Liner • Geomembrane • Geosynthetic Clay Liner (GCL) • Geocomposite Material 2

Description of Revised Guidance • New Title: Guidance for Liner Construction & Testing for a MSW Landfill • Procedures for installation & testing of liner system • Complies with regulations in 30 TAC Chapter 330, Subchapter H: Liner System Design & Operation • Status: finalize by late summer 2017 3

Document History • September 1, 1993: QA-QC for Waste Containment Facilities • July 1, 1994: Liner & Construction Handbook • July 7, 2000: Final Cover Systems Cons & Testing (Draft) • November 1, 2001: Liner Construction & Testing (Draft) 4

Noted Revisions • Flexibility for soil compaction • New section for protective cover • Low-ground-pressure equipment may travel on geomembrane • Revised geomembrane procedures: • manufacturing testing: GRI GM-13 • seaming procedures: GRI GM-9 • seam testing: GRI GM-19 5

Noted Revisions • Revised testing methods: clay liner, geomembrane, and GCL • Test Methods: geocomposite drainage layer • Flexibility for testing methods • Updated Glossary 6

Liner Quality Control Plan Regulations • 30 TAC § 330. 331: Design Criteria • 30 TAC § 330. 333: Leachate Collection System • 30 TAC § 330. 335: Alternative Liner Design • 30 TAC § 330. 337: Special Liner Design Constraints • 30 TAC § 330. 339: Liner Quality Control Plan • 30 TAC § 330. 341: SLER & GLER 7

Landfill Liner Design Basic Requirements 8

Liner System Design 9

Type I Liner • 2 -ft Protective Cover • Single / Double Sided Geocomposite • 60 -mil Smooth/Textured HDPE Geomembrane • 2 -ft Clay Liner 10

Type I Liner with GCL • 2 -ft Protective Cover • Single / Double Sided Geocomposite • 60 -mil Smooth / Textured HDPE Geomembrane • Unreinforced / Reinforced GCL 11

Class 1 Cell • 2 -ft Protective Cover • Single / Double Sided Geocomposite • 60 -mil Smooth / Textured HDPE Geomembrane • 3 -ft Clay Liner 12

Type IV Liner • Compacted Clay Liner • 1 -ft Protective Cover • 3 -ft Clay Liner • In-Situ Liner • 4 -ft In-Situ Liner • Top one foot for protective cover 13

Compacted Clay Liner Installation & Testing 14

Compacted Clay Liner Requirements • Design Values • Plasticity Index ≥ 15 • Liquid Limit ≥ 30 • Percent Passing No. 200 Sieve ≥ 30% • Percent Passing one-inch sieve = 100% • Permeability ≤ 1 x 10 -7 cm/sec 15

Soil Testing – Source Borrow Materials • Soil Classification • Moisture/Density Relationship • Sieve Analysis • Atterberg Limits • Coefficient of Permeability 16

Moisture / Density Relationship • Test: standard / modified proctor test • Results: max dry unit weight & optimum moisture content • Use parameters to compact liner Source: EPA/600/R-93/182, September 1993 17

Soil Compaction Sheepsfoot Roller Tamping Foot Roller 18

Constructed Liner – Conformance Testing • Field Density • Atterberg Limits • Permeability • Thickness Verification 19

Geomembrane Installation & Testing 20

HDPE Geomembrane • HDPE: High Density Polyethylene • Composition: • 97% polyethylene resin • 2 – 3% carbon black and additives • Typically 60 -mil Source: http: //www. geosolutionsinc. com/products/linerspvc-hdpe. html 21

Hot Wedge Seaming Hot Wedge Welding Machine Hot Wedge Seaming 22

Extrusion Welding Machine Cross Section 23

Geomembrane - Seams Source: EPA/600/R-93/182, September 1993 24

Geomembrane Manufacturer Testing • Manufacturer Testing: GRI GM-13 • Thickness • Density • Tensile Properties • Tear Resistance • Puncture Resistance • Stress Crack Resistance • Carbon Black Content • Carbon Black Dispersion • Oxidation Induction Time • Oven Aging • UV Resistance 25

Geomembrane Conformance Testing • Conformance Testing: • Thickness • Density • Carbon Black Content & Dispersion • Tensile Properties • Destructive Testing • Shear • Peal • Non-destructive Testing • Air Pressure • Vacuum Box 26

Hot Wedge Seaming – Seam Strength • Seam Strength from GRI GM 19 for 60 mil HDPE Geomembrane: • Shear Strength: 120 lb/in • Shear Elongation: 50% • Peel Strength: 91 lb/in • Peel Elongation: 25% Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 27

Extrusion Welding – Seam Strength • Seam Strength from GRI GM 19 for 60 mil HDPE Geomembrane: • Shear Strength: 120 lb/in • Shear Elongation: 50% • Peel Strength: 78 lb/in • Peel Elongation: 25% Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 28

Shear Test GRI Testing Photos 29

Shear Test – Photo 1 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 30

Shear Test – Photo 2 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 31

Shear Test – Photo 3 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 32

Shear Test – Photo 4 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 33

Shear Test – Photo 5 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 34

Peel Test GRI Testing Photos 35

Peel Test – Photo 1 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 36

Peel Test – Photo 2 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 37

Peel Test – Photo 3 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 38

Peel Test – Photo 4 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 39

Peel Test – Photo 5 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 40

Peel Test – GRI Testing Photos Photo 1 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 41

Peel Test – GRI Testing Photos Photo 2 Source: www. geosynthetic-institute. org/grispecs/gm 19. pdf 42

Geosynthetic Clay Liner (GCL) Installation & Testing 43

GCL – Summary • Bentonite layer supported by geotextiles and/or geomembranes • Held together by needling, stitching, or chemical adhesives https: //en. wikipedia. org/wiki/Geosynthetic_clay_liner 44

GCL: Non-reinforced Source: Designing with Geosynthetics 6 th ed. 45

GCL: Internally Reinforced Source: Designing with Geosynthetics 6 th ed. 46

GCL - Sodium Bentonite • sodium montmorillonite variety • naturally occurring mineral found in Wyoming and North Dakota • Properties: • k ≈ 1 x 10 -11 cm/sec • w ≥ 100% • self healing Source: http: //www. mariopilato. com/sodium-bentonite. htm 47

Geotextiles - Overview • Made from polymeric fibers • Fibers are made from polypropylene, carbon black, and additives • Once fibers are manufactured they are joined together to make a fabric or geotextile • Geotextiles are classified as woven and nonwoven 48

Woven Geotextile at 24 X Magnification Source: EPA/600/R-93/182, September 1993 49

Nonwoven Needle Punched Geotextile at 24 X Magnification Source: EPA/600/R-93/182, September 1993 50

Nonwoven Heat Bonded Geotextile at 24 X Magnification Source: EPA/600/R-93/182, September 1993 51

GCL – Installation • Subgrade preparation similar to procedures in geomembrane section • Joining GCLs is done by overlapping without sewing or other mechanical connections • Overlap distances should be marked on GCL by manufacturer (typically 6 – 12 in. ) 52

GCL - Installation • GCL with needle punched nonwoven geotextiles require bentonite in the overlap regions • Minimum Bentonite Required: 0. 25 -lb dry bentonite per linear foot of lap joint • Bentonite in lap-joint must be the same type used in the manufacture of the GCL 53

GCL – Manufacturer Testing • Bentonite • Free Swell • Fluid Loss • Geotextile • Mass / unit area • Grab Tensile Strength • Geomembrane • Mass / Unit Area • Thickness • Tensile Properties • GCL Product • Bentonite – mass / unit area • Bentonite – moisture content • Tensile strength • Grab tensile strength • Permeability • Lap Joint Permeability 54

GCL – Conformance Testing • GCL Product • Bentonite mass / unit area • Permeability • Direct shear 55

Direct Shear Device - GCL Source: Shear Strength of GCL’s, 2002 56

Direct Shear - GCL Source: Shear Strength of GCL’s, 2002 57

Interface Shear Testing GCL / Geomembrane Source: Shear Strength of GCL’s, 2002 58

Failure Envelope Source: Shear Strength of GCL’s, 2002 59

Geocomposite Material Installation & Testing 60

Geocomposite Material • Composition: geonet with a geotextile or geomembrane heat bonded on 1 or both sides • Geocomposite drainage layer has replaced granular drainage layer • Fluid flows within the geonet Source: www. gseworld. com 61

Geonets - Summary • Manufactured similar to geomembrane • Composition: • 97% polyethylene; • 2 – 3% carbon black and additives • Typically covered with a geomembrane or geotextile Source: www. gseworld. com 62

Geocomposite - Installation • Material is positioned and unrolled over substrate material (typically geomembrane) • The material is either overlapped or sewn together • In any case, follow manufacturers directions for installation and connections 63

Geocomposite – Manufacturer Testing • (Resin) Geonet • Density • Melt Flow Index • Geonet • Density • Mass / Area • Thickness • Compression • Transmissivity • Geotextile • Mass / Area • Grab Tensile Strength • Trapezoidal Tear Strength • Burst Strength • Puncture Strength • Thickness • Apparent Opening Size • Permitivity 64

Geocomposite – Conformance Testing • GCL Product • Transmissivity • Interface Shear or Ply Adhesion 65

Conclusion • Draft guidance has been posted online: http: //www. tceq. texas. gov/permitting/waste_permi ts/msw_permits/msw_liners_covers. html • We are accepting stakeholder comments until May 31, 2017. • We plan to have this document finalized by late summer 2017. 66

Questions? How to contact us: Texas Commission on Environmental Quality Municipal Solid Waste Permits Section P. O. Box 13087 MC-124 Austin, TX 78711 -3087 Phone: Fax: E-Mail: 512 -239 -2335 512 -239 -2007 mswper@tceq. texas. gov 67