2024-06-10_REVISION - M2012032 - Laserfiche WebLink

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on the drawings. The prepared surface shall be free from loose earth, rocks, rubble and other foreign matter. Generally, no rock or other object larger than USCS sand (SP) should remain on the subgrade in order to provide an adequate safety factor against puncture. Geotextiles may be used to compensate for irregular subgrades. The subgrade shall be uniformly compacted to ensure against settlement.The surface on which the lining is to be placed shall be maintained in a firm, clean, dry and smooth condition during lining installation. 1.10 Lining Installation Prior to placement of the liner, the installer will indicate in writing to the owner or his representative that he believes the subgrade to be adequately prepared for the liner placement. The lining shall be placed over the prepared surface in such a manner as to assure minimum handling. The sheets shall be of such lengths and widths and shall be placed in such a manner as to minimize field seaming. In areas where wind is prevalent, lining installation should be started at the upwind side of the project and proceed downwind. The leading edge of the liner shall be secured at all times with sandbags or other means sufficient to hold it down during high winds. Sandbags or rubber tires may be used as required to hold down the lining in position during installation. Materials, equipment or other items shall not be dragged across the surface of the liner, or be allowed to slide down slopes on the lining. All parties walking or working upon the lining material shall wear soft-sole shoes. Lining sheets shall be closely fit and sealed around inlets, outlets and other projections through the lining. Lining to concrete seals shall be made with a mechanical anchor, or as shown on the drawings. All piping, structures and other projections through the lining shall be sealed with approved sealing methods. 1.11 XR-5 Field Seaming All requirements of Section 1.04 and 1.05 apply. A visible bead should be extruded from the hot air welding process. Field fabrication of lining material will not be allowed. 1.12 Inspection All field seams will be tested using the Air Lance Method. A compressed air source will deliver 55 psi minimum to a 3/16 inch nozzle. The nozzle will be directed to the lip of the field seam in a near perpendicular direction to the length of the field seam. The nozzle will be held 4 inches maximum from the seam and travel at a rate not to exceed 40 feet per minute. Any loose flaps of 1/8" or greater will require a repair. Alternatively all field seams should also be inspected utilizing the Vacuum Box Technique as described in Standard Practice for Geomembrane Seam Evaluation by Vacuum Chamber(ASTM D 5641-94(2006)), using a 3 to 5 psi vacuum pressure. All leaks shall be repaired and tested. All joints, on completion of work, shall be tightly bonded. Any lining surface showing injury due to scuffing, penetration by foreign objects, or distress from rough subgrade, shall as directed by the owner or his representative be replaced or covered, and sealed with an additional layer of lining of the proper size, in accordance with the patching procedure. 1.13 Patching Any repairs to the lining shall be patched with the lining material.The patch material shall have rounded corners and shall extend a minimum of four inches (4") in each direction from the damaged area. Seam repairs or seams which are questionable should be cap stripped with a 1" wide (min.) strip of the liner material.The requirements of Section 1.11 apply to this cap stripping. 1.14 Warranty The lining material shall be warranted on a pro-rated basis for 10 years against both weathering and chemical compatibility in accordance with Seaman Corporation warranty for XR-5®Style 8130. A test immersion will be performed by the owner and the samples evaluated by the manufacturer.Workmanship of installation shall be warranted for one year on a 100% basis. 21