1. Storage, Transportation, and Inspection (Pre-installation Protection)
 Storage Environment Elevated Storage: Keep rolls elevated off the ground to prevent moisture accumulation. Cover completely with UV-resistant tarpaulins; strict protection against direct sunlight is required, as UV exposure rapidly degrades tensile strength and impermeability.  Temperature Control: Maintain storage temperatures between -10°C and 35°C. Keep away from open flames, welding sparks, and hot-mix asphalt. Do not stack rolls too high to prevent permanent creasing.   Handling and Transit Lifting Protection: Use wide synthetic webbing slings for lifting. Never allow steel wire ropes or sharp hooks to come into direct contact with the geomembrane. Handle with care; dragging, dropping, or tossing rolls is strictly prohibited.  Transit Shielding: Keep the truck bed covered with waterproof tarps during transport. Line the truck bed with geotextile padding to protect the rolls from punctures caused by gravel or sharp metal edges.   Incoming Quality Control (IQC) Documentation and Inspection: Verify specifications, thickness, and manufacturer test reports. Inspect each roll for pinholes, tears, severe creases, impurities, and air bubbles. Damaged or non-compliant rolls must be rejected immediately.
 2. Subgrade and Subsurface Preparation (Critical Puncture Prevention)
Debris Clearance: Completely clear the subgrade of all sharp protrusions, including stones/gravel larger than 5mm, tree roots, rebar, and construction debris.  Compaction and Leveling: Compact and level the subgrade to a minimum compaction rating of 95%, with a maximum deviation of  under a 2-meter straightedge. Soft mud or quicksand zones must be excavated and backfilled with a sand-gravel cushion.  Cushion Layer Requirement: For high-risk containment projects (such as municipal solid waste landfills and chemical ponds), a non-woven geotextile cushion must be installed underneath to serve as a puncture barrier.  Corner Geometry: Smooth all inside and outside corners, as well as slope transitions, into a radius (). Avoid sharp 90-degree angles to prevent stress concentration and subsequent cracking of the membrane.
 3. Installation and Deployment Guidelines
1. Environmental and Weather Restrictions (Mandatory Work Stoppage) Temperature Limits: The optimal installation temperature is between 5°C and 40°C. Below 5°C, the geomembrane must be preheated, and welding temperatures adjusted upward. Above 40°C, avoid midday operations to mitigate thermal expansion.  Adverse Weather: Halt all deployment and welding operations if wind speeds exceed Beaufort Scale 5 (-grade wind), or during rain, snow, heavy fog, or when the subgrade is wet/saturated. Resume work after rain only when the subgrade is completely dry.
 2. Slack Management and Deployment Thermal Compensation: Deploy the geomembrane smoothly with a 1% to 3% slack allowance. Tight stretching is strictly prohibited; failure to accommodate thermal expansion and contraction will lead to localized tearing or seam failure over time.  Slope Placement: Deploy panels parallel to the slope line (from bottom to top) to minimize horizontal seams. Use the maximum available panel width to reduce the total number of field seams.
3. Overlaps and Temporary Anchoring Seam Standards: The standard overlap width for thermal fusion welding must be . The seam area (up to 30cm wide) must be completely dry, clean, dust-free, and oil-free prior to welding.  Ballasting: Use sandbags wrapped in soft fabric to temporarily ballast the liner against wind uplift. Hard or sharp heavy objects must never be placed directly on the membrane.