Installation Procedures

 PPL CONTAINMENT MEMBRANES
LONG TERM STORAGE/CONTAINMENT MEMBRANE
CONTAINMENT MEMBRANE QA/QC & INSTALLATION PROCEDURES

1. SCOPE OF WORK:
   Furnish and install a flexible membrane lining as shown on engineering or contractor supplied drawings. All work shall be done in strict accordance with the drawings and related specifications and the membrane lining manufacturer's recommendations.
   
   It is the intent of these specifications to insure a quality finished product as described on the plans and specifications and shall be the responsibility of the contractor to take whatever measures shall be deemed necessary to insure that this requirement shall have been met.
   
   All interested governmental agencies shall provide inspection services throughout the installation procedure or provide written acceptance of the installation after final inspection.
   
   
   
2. PRODUCT:
   The material supplied under these specifications shall be first quality goods specifically formulated and tested for the containment of the material(s) as set forth in the accompanying specifications.
   
   The material used for the lining shall be a high density polyolefin reinforced low density polyethylene membrane and shall have been satisfactorily demonstrated by prior use and testing to be suitable, appropriate and durable for the purpose of this work.
   
   The membrane shall be manufactured by the application of Low Density coating over High Density scrims and shall be uniform in color, thickness, size and surface texture.   The finished lining shall be a sunlight (UV) and weather resistant (Cold temperature),plant and fish safe membrane that is a flexible, durable, liquid tight product free from pinholes, blisters, contaminates or other off specification defects.
   
   The membrane shall be manufactured from a composition of high quality ingredients, specifically compounded for use in hydraulic structures.   Only domestic resins and additives shall be used.   Reprocessed materials will not be acceptable other than clean rework materials of the same virgin ingredients generated from the manufacturer's own production.
   
   The finished membrane liner shall consist of 2/2.5 mils of LD polyethylene coating over 2 HD scrims followed by 2/2.5mils of LD coating creating a 5 layer impermeable membrane with tremendous strength and resistance to hydrocarbons.   The finished thickness shall be plus or minus 10% based on the material type i.e. PPL20,PPL24, PPL36 etc.
   
   
   
3. ROLL SAMPLING:
   Each roll upon delivery shall be visually inspected. Each roll shall be wrapped individually and each roll shall be clearly labeled with a roll number and lot number. Each load will be accompanied by a box of samples 6" x 12', for each roll delivered, for archiving and sampling.
   
   Prior to placing the roll into production, the roll number and lot number will be recorded on the inside of the core with permanent marker. A 6" wide sample taken from the entire width of the roll will be removed and cut into 2 pieces 6" x 6'. long and welded together for sampling and material integrity testing. Peel testing of the sample shall be done to insure weldability and careful inspection at weld separation shall be checked for delamination. If delamination failure is present, retest as described above, after removing 15 feet from the roll. If failure is still apparent the roll shall be labeled as rejected and removed from the production area. These procedures apply to all new rolls and roll splice joints.
   
   All roll tests are to be recorded in the test log.
   
   
   
4. FABRICATION:
   The individual widths of the PPL fabric shall be assembled into large sheets custom-designed for the specific project so as to minimize field seaming.  All factory seams shall provide a bond between the sheet goods sufficiently strong to meet the test requirements of these specifications.
   
   All machines used in the seaming process shall be tested daily, prior to any fabrication, by welding a 6'long test sample of the material and manually peel testing along the entire length. Each test must show film tear bonding along the length of the seam to be considered a "pass". All results shall be recorded in the test report log and must include Date, time, machine #, operator, temp and speed as well as passfail indication. If the sample fails the testing, make appropriate corrections to the equipment and retest as stated above.
   
   Machines will be further requalified after the following: change of material, unexpected power loss, change of operator, or shutdowns of 45 minutes or longer.
   
   The factory seaming shall be performed on thermal welding equipment with pressure wheels and shall consist of seams of 2" minimum width in the case of wedge welding, 1.5" width in the case of hot air welding, which will provide a film-tearing bond of 80% of the fabric tensile strength.  All seams shall be visually inspected along there entire length, and destructive tested at an interval not to exceed 500 lineal feet of factory seam per machine.
   
   
   
5. PANEL PACKAGING AND HANDLING:
   Factory fabricated panels shall be accordion folded during production to width of approximately 6' wide. Upon completion each bundle shall be folded or rolled by hand or machine based on the total square footage of the panel. Panels 10,000 sq.ft. or larger are rolled by machine and include a core and continuous unroll strap.  Each roll shall be secured to a pallet or export container designed to be moved by a forklift or similar piece of equipment.   Each factory-fabricated panel shall be prominently and permanently marked with the panel size and installation location as per factory drawings. Each panel will then be wrapped with its own protective wrap and marked again as to size and installation location. Packaged factory liner sections, which are delivered to a project site, shall be stored in their original shipping wrappers and stored in a dry area and protected from harsh weather elements when at all possible. The liner sections shall not be stacked.
   
   
6. INSTALLER:
   The installer of the lining fabric shall be experienced in the installation of flexible membrane linings and shall be approved in writing by the fabricator and the manufacturer of the material.
   
   
7. LINING BASE MATERIAL:
   A base shall be prepared on the bottom and slopes of the area to be lined.  This base shall be free of all sharp objects, roots, grass and vegetation.   Unsuitable material found during the pre-installation inspection by the installer shall be removed prior to the installation of the liner.
   
   The base (subgrade) material shall be native materials or materials obtained from a borrow source compacted to a minimum 95% compaction or an approved construction fabric of at least 100 mils thickness, weighing 8 ozs. per square yard with a grab tensile strength of at least 275 lbs. per square inch and a Mullen burst strength of at least 450 pounds per square inch, which will provide a finished sub grade suitable for the flexible membrane lining.
   
   Foreign materials, vegetation, protrusions, voids, cracks and other penetrating or raised sources shall by removed from the sloping areas as well as the base.  Loose rocks, rubble and other foreign matter shall be collected and deposited in the appropriate site out of the area to be lined.  The excavated and filled areas shall be trimmed to elevations and contours shown on the drawings and shall be smooth, uniform and free of all foreign matter, vegetation and sudden changes in grade.
   
   A pre-installation inspection shall be called for and ALL interested parties, including governmental agencies, shall be present for this inspection.   Any parties not participating in this inspection shall be construed as accepting the site preparation and will acknowledge this defacto acceptance in writing at the appropriate time
   
   
   
8. FINAL SUBGRADE PREPARATION:
   The sub grade shall be prepared immediately prior to the placing of the liner.  The surface on which the liner is to be placed is to be firm, clean, dry and smooth.  Anchor trench excavation and any structure seal preparation should be completed before the lining installation begins.
   
   
9. LINING INSTALLATION:
   A continuous sheet of liner shall be installed throughout the installation site as according to the drawings.  The lining shall be placed over the prepared surfaces to be lined in such a manner as to assure a minimum of handling.  The sheets shall be of prescribed lengths and widths and shall be placed in such a manner as to minimize field seams.  Only those pieces of fabric that can be installed and anchored in place during the workday shall be unpacked and placed in position.
   
   Sandbags and or other suitable weights may be used as required to hold the lining in position during the installation.  The weights shall not have any sharp edges, which may snag or otherwise penetrate the liner fabric. Care should be taken to keep the seam areas as clean as possible.  It may be necessary to wipe down the edges prior to heat-sealing the panels together.
   
   No materials or equipment shall be dragged across the face of the liner nor shall the workmen while installing the liner subject the liner to abuse.   All installation party members shall wear soft-soled shoes or boots while working on the surface of the liner.
   
   Lining sheets shall be closely fit around all penetrations through the liner.   Lining to concrete seals shall be affected with mechanical anchors as shown on drawings.   All piping, structures and irregular projections shall be sealed and flashed with the fabricated boots or other approved sealing methods.
   
   A meeting of all interested parties shall proscribe the method of backfilling of the site with the appropriate materials.   The lining installation manager prior to commencement of the backfilling program shall approve all actions undertaken to place the top cover material.
   
   
   
10. FIELD SEAMS:
    All seaming shall be done with thermal heat-sealing equipment or with the adhesives of the lining fabric manufacturer's brand.   Heat-sealing with automatic wedge welding is the preferred method of field seaming whenever possible.
    
    Wedge welders for field seams shall be qualified prior to beginning field seaming. A 6' section of material, at current ambient temperature, shall be welded and manually torn apart to insure proper welding adhesion.
    
    Lap joints require a minimum of 2.5" overlap of the factory fabricated panels.  The contact surfaces of the panels must be cleaned and all moisture and other foreign material must be removed prior to heat sealing.
    
    If the sub-surface area is not capable of 95% compaction it may require the placement of a back board or rub sheet under the liner to give a firm, dry and clean welding surface.
    
    Extreme caution should be taken throughout the installation to avoid wrinkling the edge of the liner.  These "fish mouths" must be slit back sufficiently to remove them and the liner sealed to assure total integrity.
    
    Any portion of the liner damaged or hurt for any reason shall be repaired or replaced by the installation crew before it departs.  Normally the ends of the panels can be used for a patching source.
    
    
    
11. PATCHING:
    Any repairs resulting from damage during installation shall be repaired with like fabric and heat sealing to ensure a secure lining.  It is recommended that at least 2"-4" of overlap be used on any penetrations.  It is suggested that any major scuffing be replaced with undamaged liner.
    
    
12. INSPECTION:
    A thorough inspection of the completed liner installation shall be undertaken by a representative of the installer and a representative of the owner or the engineer in charge of the project. All government agencies involved in the project should also have an inspector or designated representative on site during the installation and after completion of same so as to register any complaints at that time.  Any and all discrepancies to the permit process or license shall be attended to at this time.
    
    
13. FIELD TESTING:
     All field seams shall be visually inspected along their entire length for integrity.  If required by contract seams and repairs may additionally require non destructive testing using the Air Lance method (ASTM D4437) as outlined:  
    A   Installer will supply a compressor and air wand with a fixed nozzle tip with an opening approx. 3/4" wide x 1/8" high.
    B   Compressor shall be equipped with an output gauge and the ability to continuously supply 30 psi of air pressure.
    C   The non destructive test involves running the nozzle of air 1/4" to 1/2" away from the outside edge of the field seam for its entire length. If air penetrates the seam area the audible noise or visual puffing of the seam indicates an area of concern and should be marked and repaired accordingly.
    
    
    
14. SOIL COVER:
    PPL geomembranes may be covered by soil if desired. In areas of high traffic or areas with a high water table covering the entire liner is often recommended.
    
    Care should be taken when covering the liner to prevent any damage to the geomembrane or geosynthetics. At no time will construction equipment be allowed to drive directly on the liner. Access roads for soil cover should be maintained to provide 6" minimum, 12" preferable, between the excavation equipment and liner at all times. Damage to the liner, shall be repaired prior to proceeding with cover. Costs associated with repairs are the contractor's responsibility.
    
    **Cover material shall be 1/2" minus particles, clean rounded soils or gravels, free of sharp edges,sticks, rubbish and debris or foreign materials. The cover material shall be placed as soon as practical, upon completion of the liner installation, or in conjunction with, as the installation progresses to minimize traffic.
    
    Cover soils should be dumped and leveled over the liner and not pushed from one end to the other to minimize rolling of the geomembrane beneath the soils. Cover soil should always be placed from the base up on slopes never pushed from the top of the slope downwards. Equipment should be turned in long sweeping turns and not spun quickly to eliminate the chance of digging down to the liner thru the cover soil.
    
    When covering or initially filling a liner it is important not to lock the liner into the perimeter anchor trench prior to covering. This can cause undue stress and tension on the liner slopes during the covering process. The anchor trench or perimeter shelf area should be the last area covered to complete the cover process.
    
    ** Site specific materials or sizes may be acceptable. It is recommended that the contractor receive prior written approval for acceptance of the cover materials, from BTL representative, before covering the liner.
    
     

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