LiteEarth Advanced Synthetic Grass Geomembrane Liner INDEPENDENT THIRD PARTY PERFORMANCE TESTING REPORT. U.S. Patent No.

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1 LiteEarth Advanced Synthetic Grass Geomembrane Liner INDEPENDENT THIRD PARTY PERFORMANCE TESTING REPORT U.S. Patent No B2

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3 Contents 1.0 INTRODUCTION INDEX AND QUALITY CONTROL TESTS 2.1 Physical Properties Mechanical Porperties PERFORMANCE AND DESIGN TESTS 3.1 Mechanical Porperties Hydraulic Porperties Flume Testing DURABILITY SEAM STRENGTH ANCHOR PULLOUT AND WIND UPLIFT... 12

4 1.0 INTRODUCTION LiteEarth U.S. Patent No B2 is an advanced synthetic grass and EPDM geomembrane liner designed to be used as an alternative to conventional landfill closure caps. Since no soil cover is needed with LiteEarth, it falls within the category of exposed geomembrane covers. However, an important difference between exposed geomembrane and LiteEarth is that the latter is not completely exposed in the sense that a geomembrane is but is covered with a synthetic grass. As such, the average lifespan of LiteEarth is much longer than geomembrane-only exposed covers, in which the geomembrane is not protected from the elements of nature. EPDM Long-Term Performance Predicted Geomembrane lifetimes based on 50% reduction of strength and/or elongation. Note: Tested as an Exposed Geomembrane Type Specification 1 Strength Ret. (%) & Exposure (lt. hrs.) Elongation Ret (%) & Exposure (lt. hrs.) Comment Half Life 2 HDPE mm (0.060 ) GRI-GM13 51,000 51,000 ongoing 42+years LLDPE mm (0.040 ) GRI-GM17 48,000 43,500 half-life reached 36 years fpp mm (0.045 ) GRI-GM18 40,300 40,300 ongoing 33+ years EPDM mm (0.040 ) GRI-GM21 43,200 43,200 ongoing 36+ years* NOTES: (1) See the GSI Website at for the most recent version. (2) Based on the correlation factor of 1200 lt. hrs.=1.0 years in a hot climate such as West Texas and Southern California Source: * LiteEarth s 45 mil EPDM is covered by compound adhesive, a UV stabilized primary and high-grade monofilament turf that reduces the amount of UV exposure to EPDM. Being a single product, monolithic material, LiteEarth offers several advantages over multi-layered synthetic turf systems that use sand as ballast. These include faster installation, lower cost, better quality of grass and no erosion concerns. LiteEarth composite consists of the following three components: 1) Synthetic Grass with UV stabilized woven geotextile 2) EPDM Geomembrane Liner 3) Advanced Composite Adhesive Figure 1: LiteEarth components GSEworld.com Performance Testing Report 4

5 The synthetic grass is both an aesthetic and functional component of the product and is visible when viewing an installation of LiteEarth. The woven geotextile is a highly UV stabilized product that acts as a carrier or backing for the grass. The synthetic grass is manufactured in an ISO 9001 quality control facility to ensure compliance with both project specifications and environmental standards. The grass is mechanically attached to the geotextile through a tufting process. Figure 2: Tufting Process The carrier geotextile with tufted grass is then laminated to the geomembrane using an industrial adhesive. The finished product is available in roll sizes 15 feet wide (14 feet of turf with 1 feet of blank) by up to 200 feet long. EPDM Compression Rollers Inspection QC Composite Adhesive Heated Roller Figure 3: Advanced Synthetic Elastomer Bonding Technology Advanced Synthetic Grass Geomembrane Liner 5

6 2.0 INDEX AND QUALITY CONTROL TESTS 2.1 PHYSICAL PROPERTIES The physical properties are the most basic of the material properties and are used for quality control, quality assurance and material conformance evaluation purposes. Since the measurement methods and equipment are simple, these tests generally have a higher precision and lower bias than more complex tests within mechanical and hydraulic categories. Physical tests on geosynthetics generally include thickness, mass, density and dimensions. Table 1 presents these property values for the LiteEarth composite product, i.e., the finished material as shipped to job sites. Figure 4: Physical Evaluation Process Table 1 Physical Properties of LiteEarth Property Test Method Units Average Value Thickness ASTM D 5199 mil (mm) 422 (10.7) Mass per Unit Area ASTM D 751 oz/yd2 (g/m2) 80 (2,747) Density ASTM D 792 g/cc to 1.1 Linear Dimensional Change (max)* ASTM D 1204 % ±1 Roll Width ft (m) 14 (4.2672) turf with 1 (.3048) blank Roll Length ft (m) Up to 200 (60.96) NOTES: * Tested on EPDM Geomembrane A review of Table 1 shows that LiteEarth is a robust material with a much greater thickness and mass than geomembranes and even drainage geocomposites alone. An advantage of this robustness is an intrinsic resistance of the material to damage, waves and wind uplift. The high mass of the material, when combined with synthetic grass and a low coefficient of thermal expansion, makes it possible to install LiteEarth in a wrinkle-free state. As a thermoset material, the properties of LiteEarth listed in Table 1 make it a distinctly superior material compared to certain polyethylene geomembranes that are difficult to install and seam due to large waves and wrinkles resulting from their higher coefficient of thermal expansion. 2.2 MECHANICAL PROPERTIES While the physical properties in the previous section measure such characteristics as density and dimensions, the mechanical properties are employed to evaluate the resistance of the product to stress. Since the values depend on the shape of the test specimens as well as the rate of loading, there are several types of test methods. Geomembranes made from different polymers are GSEworld.com Performance Testing Report 6

7 generally tested using different test methods. Moreover, it is often necessary to evaluate mechanical properties for different loading scenarios such as planar load, point stress and multi-axial deformation. Due to the test methods being different and of an index nature, it is not possible to compare different products with these methods or use these methods for the purpose of design. The mechanical properties in Table 2 should be used only for quality control and conformance testing purpose. Table 2 Index Mechanical Properties Property Test Method Units Average Value Tensile Strength (peak) Tensile Strength (peak) Tensile Strength (peak) Tensile Strength (peak) Tensile Strength (peak) ASTM D 412, Die C psi (MPa) 2,424 (16.7) 1,498 (10.3) ASTM D 412, Die C psi (MPa) 1,123 (7.7) 908 (6.3) ASTM D 412, Die C % ASTM D 412, Die C % ASTM D 624, Die C lb/in (g/cm) 194 (34,600) 159 (28,300) Puncture Strength ASTM D 4833 lb (N) 130 (578) Ply Adhesion (GM-GT) Peel Strength ASTM D 7005 lb/in (g/cm) 5.5 (980) The peak values for the strength and strain in the table represent the stress point at which the woven geotextile breaks. The ultimate values represent the breakage of the geomembrane which occurs at a much higher strain than the peak value. As a result of the composite action, tear and puncture values for LiteEarth are much higher than those for the geomembrane and the geotextile alone. Therefore, the primary backing not only supports the grass but also significantly improves the mechanical properties of the product. Since the finished product consists of a woven geotextile backing and an EPDM geomembrane bonded together with a high performance adhesive, lamination strength is given as well. The comparison of LiteEarth to polyethylene geomembranes based on mechanical properties is covered in the next section. 3.0 PERFORMANCE AND DESIGN TESTS 3.1 MECHANICAL PROPERTIES Mechanical design properties are used for various calculations such as wind uplift, differential settlement, protection from puncture, and connection to rigid structures. As such, mechanical performance tests involve a much larger size test specimen as compared to index tests and mimic the field conditions as much as possible. For geomembranes and related materials, there are three types of mechanical performance tests: wide width, multi-axial and puncture. A wide width test models field conditions where a material is loaded in its plane as it may occur, for example, during unwinding a roll or as a result of movement of different materials at their interfaces in a shear mode. A multi-axial test simulates the out-of-plane deformation that may occur due to the equipment loading from the top or subsidence at the bottom or wind uplift. A puncture test represents a relatively small size object, such as a stone or stick piercing through the material. The performance mechanical properties of LiteEarth in Table 3 again indicate the composite nature of the material characterized by a peak, where the geotextile breaks, followed by the final or ultimate value representing the geomembrane properties. For the wide width test, the geomembrane rupture does not occur to the limit of the equipment, therefore, no ultimate properties are reported in Table 3. Advanced Synthetic Grass Geomembrane Liner 7

8 Figure 5: Mechanical Evaluation Process Table 3 Performance Mechanical Properties of LiteEarth Property Test Method Units Average Value Wide Width Tensile Strength (peak) Wide Width Tensile Strain (peak) ASTM D 4595 lbs/ft (kn/m 1,300 (19) 1,632 (24) ASTM D 4595 % Multi-Axial Tensile Properties (peak) Strength Strain ASTM D 5617 psi (kpa) % 1,092 (7,529) 19 Multi-Axial Tensile Properties (ultimate) Strength Strain ASTM D 5617 psi (kpa) % 23.5 (162) 119 CBR Puncture Strength ASTM D 6241 lb (kn) 842 (3.7) Table 3 shows that the flexibility of the geomembrane is not compromised by bonding it to the synthetic turf. For landfill covers which may go through a significant amount of differential and total settlement, it is the flexibility of the geomembrane, characterized by strain or elongation, that is the most important property. The peak wide width and multi-axial strain values in the table show a behavior typical of a woven geotextile. The break strain of EPDM from wide width (not reported in the table) and multi-axial tests are similar to or superior to the published results for linear low density polyethylene (LLDPE) geomembranes. Test Performance Comparison Physical Characteristic Standard Units LiteEarth 1 EPDM 2 HDPE 3 LLDPE 4 Thickness (min. ave./ lowest indiv.) ASTM D 5119 mil 422 / / / / 45 Puncture Resistance ASTM D 4833 lbs Linear Dimensional Change (max) ASTM D 1204 % < +/-1.0 < +/-1.0 +/-2.0 +/-2.0 Multi-Axial Elongation (min) ASTM D 5617 % 19/ NOTES: (1) LiteEarth consists of a 45 mil non-reinforced EPDM liner factory bonded to a 4.4 oz/sy, 1/2 tufting gauge single layer 18 pic woven polypropylene primary (2) 45 mil, non-reinforced EPDM per GRI Test Method GM21 (3) 50 mil textured HDPE, per GRI Test Method GM13 (4) 50 mil textured LLDPE, per GRI Test Method GM17 (5) Testing conducted by TRI-Primary rupture/ EPDM rupture GSEworld.com Performance Testing Report 8

9 For example, Designing with Geosynthetics cites more than 400% strain for LLDPE in a wide width test and 75% strain in an axi-symmetric (multi-axial) test. EPDM the liner component of LiteEarth - shows more than 400% strain in wide width mode and 119% in axi-symmetric mode. Thus, while the backing exhibits the characteristics of a woven geotextile, the ultimate properties are typical of EPDM geomembrane and meet or exceed the strain values when compared to LLDPE geomembranes. 3.2 HYDRAULIC PROPERTIES LiteEarth is a barrier meant to be used primarily for exposed applications. As such, it must isolate the underlying waste from the environment by minimizing the outward migration of harmful gases and any infiltration of water into the waste. The flow of gases and water through geomembranes occurs through the process of diffusion according to Fick s Law. Researchers have evaluated a number of geomembranes and found that the diffusion through most commercially available geomembrane ranges within one order of magnitude. Therefore, the type of polymer of a geomembrane has some influence on diffusion but this is generally not large enough to be the basis of the preference of one geomembrane over the other unless aggressive solvents are involved. Table 4 presents the hydraulic properties of LiteEarth. Table 4 Performance Hydraulic Properties Property Test Method Units Average Value Water Vapor Transmission*, Darcian Permeability ASTM E 96 cm/sec 1x10-12 Methane Gas Permeability Coefficient* ASTM D 1434 cm 2 /sec/pa 7.5x10-13 * = tested on 45 mil EPDM geomembrane alone 3.3 FLUME TESTING Large-scale flume testing on LiteEarth was performed at TRI s Denver Downs Research Farm (DDRF) facility in Greenville, SC. The purpose of the test was threefold: 1) obtain Manning s Roughness Coefficient, n; 2) determine tractive shear stresses; and 3) assess any loss of grass from the material as a result of the tractive shear stresses. The test was performed in a 2 ft by 40 ft concrete flume at a 20% slope. The LiteEarth test sample was secured against the flume using metal strips and the edges of the sample were sealed against the flume walls with an adhesive. The material was tested under the following four water flow depths in the order of increasing severity: 2.3 in, 4.0 in, 6.7 in and 10.7 in. At each depth, the flow was maintained for 30 minutes in order to assess the mechanical integrity of the material. Figure 6: Flume Testing Advanced Synthetic Grass Geomembrane Liner 9

10 Table 5 summarizes the test results obtained from the flume tests. The third and the last columns show velocity and tractive shear stresses, respectively. Both of these parameters indicate that soil erosion would occur if sand was used as an infill material. Since LiteEarth does not utilize any soil infill, the tests did not result in any loss of soil. Moreover, since the synthetic grass fibers are connected mechanically to the carrier geotextile, no loss of the turf was observed during the tests. The Manning s n values in Table 5 confirm the behavior of LiteEarth as being equivalent to a layer of well-established natural grass. Table 5 Large Scale Flume Testing (ASTM 6460) Shear Level Flow Depth (in) Flow Velocity (ft/sec) Flow Rate (ft 3 /sec) Manning s Roughness, n Max. Bed Shear Stress (lbs/ft 2 ) DURABILITY Durability testing on geosynthetics is generally of two types: 1. Chemical and 2. Ultraviolet (UV). The former evaluates the compatibility of a geosynthetic with a specific chemical or landfill leachate while the latter evaluates resistance of a material to aging when exposed to the sunlight. Chemical durability to landfill leachate is typically performed according to the EPA 9090 test method. However, over 20 years of EPA 9090 testing has revealed that most commercially available geosynthetics, including EPDM geomembranes, do not degrade at all when exposed to landfill leachate. Therefore, EPA 9090 testing is rarely performed anymore on geosynthetics. Figure 7: UV Evaluation Process GSEworld.com Performance Testing Report 10

11 A more important concern, especially for exposed materials, is their resistance to aging from UV light exposure. There are two types of UV tests: index and performance. The index or quality control tests are used to ensure that the material formulation and compounding is consistent. These tests also serve as an indicator of the long-term performance. Examples of these tests include Oxidative Induction Time (OIT) on polyethylene geomembranes and UV Resistance (ASTM D 4355) tests on geotextiles. The long-term UV tests are performed in weatherometers under conditions that more closely simulate the actual exposure conditions of projects. Both short-term and long-term UV aging tests on LiteEarth and its components are summarized in Table 6. The top two rows in Table 6 show the performance UV test results for the grass and the EPDM geomembrane. This type of UV performance is generally inferred as showing a design life exceeding 30 years. The primary backing UV results show the geotextile having significantly better UV performance than most commercially available geotextiles. And EPA 9090 testing shows that similar to other geosynthetics, a typical landfill leachate has no effect on the EPDM properties. Table 6 Aging and Compatibility Tests on LiteEarth and its Components Property Test Method Units Average Value Grass Fiber UV Resistance ISO :2006(E) % Breaking strength 50% > 34,000 hours EPDM Geomembrane UV Resistance* ASTM D 7238 at 70 C % Breaking strength % Pigment retention 82% at 43,200 hours 52% at 43,200 hours Primary Backing UV Resistance ASTM D 4355/D 5035 % Breaking strength 95% at 1000 hours EPDM Geomembrane Leachate Compatibility EPA 9090 No Change * The Geosynthetic Institute testing 5.0 SEAM STRENGTH LiteEarth utilizes EPDM a high performance thermoset geomembrane as the liner. As such, all the panel-to-panel seaming must be achieved using an industrial grade butyl adhesive recommended by the manufacturer. The seaming procedure is very simple and has been used for years in many industries. Physical Characteristic Standard Units EPDM 1 HDPE 2 LLDPE 3 Seaming Tape Thermal Weld Thermal weld Seaming inspection method 30 Lance ASTM 5820 Pressure Test Peel Strength ASTM D 7272 ppi 28 Shear Strength ASTM D 7272 ppi 144 Peel Strength ASTM D 6392 ppi Shear Strength ASTM D 6392 ppi NOTES: (1) 45 mil non-reinforced EPDM seamed to polypropylene primary, as tested by TRI (2) 50 mil textured HDPE, GM13 (3) 50 mil textured LLDPE, GM19 - LiteEarth Liner Roll size: 15 x 200 w/12 (for mechanical anchors) and seaming - Industry proven bonding adhesive technology with rapid flash-off and curing cycle One edges along the side of a panel is manufactured with approximately one foot of the material without the grass. A thin coat of primer is applied to the top surface of one panel with the geotextile and the bottom surface of another panel with the geomembrane. A 6 wide butyl adhesive strip is placed between the primed surfaces which are then joined under slight pressure. This procedure achieves a strong and durable seam that is impermeable to both water and air. Table 7 presents seam strength test results for LiteEarth. Advanced Synthetic Grass Geomembrane Liner 11

12 Table 7 Seam Strength Tests on LiteEarth Property Test Method Units Average Value Peel Strength ASTM D 7272 lb/in (kn/m) 29.4 (5.1) Peel Locus of Failure ASTM D 7272 lb/in (kn/m) AD2/SIP Shear Strength ASTM D 7272 lb/in (kn/m) (26.2) Shear Locus of Failure ASTM D 7272 lb/in (kn/m) AD1/AD2 6.0 ANCHOR PULLOUT The LiteEarth artificial turf installation procedure involves pinning the turf material down via the use of earth anchors installed into the soil foundation layer. A relevant analysis of this system is a test of the ability of the LiteEarth artificial turf material to withstand pull-through of the plates. As the anchors are installed through the EPDM geomembrane and are stressed in application, the anchor plates and geomembrane must supply a resistance for the system to be successful. The pull-through test is performed by clamping a sample of LiteEarth artificial turf over an anchor plate equipped with an anchor. The anchor is pulled vertically and the anchor plate and turf are challenged to resist pull-through. The figure on this page shows the test as performed. The anchor pull-through tests resulted in an average pull-through resistance of 1,300 pounds for 3 anchor plates and 2,429 pounds for 6 plates. Table 8 presents anchorage recommendations for LiteEarth based on the laboratory data and wind uplift calculations. Figure 8: Anchor Evaluation Process Table 8 Anchorage Recommendations for LiteEarth Hurricane Category Wind Speed (Miles/Hour) Anchor Spacing (ft) Anchorage Force (lbs) Anchor Plate (in.) I II III IV GSEworld.com Performance Testing Report 12

13 GSE is a leading manufacturer and marketer of geosynthetic lining products and services. We ve built a reputation of reliability through our dedication to providing consistency of product, price and protection to our global customers. Our commitment to innovation, our focus on quality and our industry expertise allow us the flexibility to collaborate with our clients to develop a custom, purpose-fit solution. For more information on this product and others, please visit us at GSEworld.com, call or contact your local sales office. REV 27FEB2017