The liner installer is responsible for the following:

1. Equipment or tools shall not damage the geomembrane by handling, trafficking, or other means.

2. Personnel working on the geomembrane shall not smoke or wear damaging shoes.

3. The method used to unroll the panels shall not score, scratch or crimp the geomembrane, or damage the supporting soil.

4. The method used to place the panels shall minimize wrinkles.

5. Adequate loading (e.g., sand bags or similar items that will not damage the geomembrane) shall be placed to prevent uplift by wind. In cases of high wind, continuous loading is recommended along edges of panels to minimize risk of wind flow under the panels.

6. Direct contact with the geomembrane shall be minimized; i.e., the geomembrane in traffic areas shall be protected by geotextiles, extra geomembrane, or other suitable materials.

Approved seaming processes are hot wedge fusion and extrusion fillet welding. On side slopes, seams shall be oriented in the general direction of maximum slope, i.e., oriented down, not across the slope. In corners and odd-shaped geometric locations, the number of field seams shall be minimized.

No base T-seam shall be closer than 5 feet from the toe of the slope. Seams shall be aligned with the least possible number of wrinkles and "fishmouths." If a fishmouth or wrinkle is found, it shall be relieved and cap-stripped.

7.2   Seam Overlap

Geomembrane panels must have a finished minimum overlap of 4 inches for hot wedge fusion welding and 6 inches for extrusion welding.

Cleaning solvents may not be used unless the product is approved by the liner manufacturer.

7.3   Field Seam Testing

Field test seams shall be conducted on the liner to verify that seaming conditions are satisfactory. Test seams shall be conducted at the beginning of each seaming period and at least once each 4 hours, for each seaming apparatus and personnel used that day.

All test seams shall be made in contact with the subgrade. Welding rod used for extrusion welding shall have the same properties as the resin used to manufacture the geomembrane. The test seam samples shall be 10 feet long for fusion welding and 3 feet long for extrusion welding with the seam centered lengthwise. Five specimens shall be cut from each end of the test seams by the inspector. The inspector shall use a tensiometer to test 5 specimens for shear and 5 specimens for peel. Each specimen shall be one inch wide with a grip separation of 4 inches plus the width of the seam. The seam shall be centered between the clamps. The rate of grip separation shall be 2 inches per minute. Test results for seam strength properties shall be the average of five specimens. Four out of five specimens shall pass seam acceptance criteria. Shear and peel tests shall result in Film Tearing Bond (FTB), which is a failure in ductile mode of one of the bonded sheets by tearing prior to complete separation in the bonded area. If a test seam fails to meet field seam specifications, the seaming apparatus and/or seamer shall not be accepted and shall not be used for seaming until the deficiencies are corrected and a successful test seam is achieved.

8.  WEATHER CONDITIONS

Liner deployment shall proceed between ambient temperatures of 32° F to 104° F. Placement can proceed below 32° F only after the installer demonstrates to the inspector that the material can be seamed to meet the project specifications. Geomembrane shall not be placed during precipitation or moisture of any type (e.g. fog, rain, dew), or in the presence of excessive winds, as determined by the installation supervisor. Observation of temperature, humidity, precipitation, and wind should be noted to ensure that weather conditions are acceptable prior to liner placement.

9.  SEAMING EQUIPMENT AND ACCESSORIES

Approved equipment for field seaming are hot wedge fusion welders and extrusion fillet welders.

1. Hot Wedge Welder, 110 Volt (220 Volt).
2. Extrusion Welder, 220 Volt.
3. 6.5 KW Generator, single-phase with 110/220 Volt Outputs.