SCOPE

The work specified in this section covers all labor, material, transportation and service necessary for the Installation of Pre Fabricated Lining (Geomembrane) on the Ash Pond as shown on the drawing or as directed by the Owner.

WORK INCLUDED

Furnishing and installing of material

Preparing of Subgrade

Furnishing Vegetation Control as necessary

Performing all test required

WORK NOT INCLUDED

Excavating and filling for construction of Pond

CODES AND STANDARDS

Comply with the requirements of the applicable codes and standards published by the following organizations:

ASTM American Society for Testing and Materials

FTMS Federal Test Method Standard

Conform especially to the applicable provisions of the following Codes and Standards

ASTM D 1505 Density of plastic by the density - gradient

ASTM D 1238 Flow rate of thermo plastic - technique by extrusion plastometer

ASTM D 638 Tensile properties of plastic

ASTM D 1004 Initial tear resistance of plastic sheeting

FTMS 101 C2065 Federal Text Method standard for puncture resistance etc.

Subject to the Owner's approval the Contractor may perform the work according to the provisions of other national and international codes and standards.

QUALITY ASSURANCE/QUALITY CONTROL (QA/QC)

Contractor shall fully comply with the Project Quality Assurance/Quality Control Requirements. For submitting quality assurance/quality control procedures and documentation the provision of clause “Submittals” of this Specification apply.

SUBMITTALS

After the Contract Signed, The Contractor shall furnish complete and comprehensive data of material specification from Manufacturer for the Owner's approval.

Test procedure, installation procedure, test report shall be documented by the Contractor and submitted to the Owner for approval.

DELIVERY AND STORAGE

DELIVERY

Geomembrane rolls or panels shall be packaged and shipped in good manner that shall protect them for damage

Geomembrane shall be delivered to the site in a good condition

The Contractor shall be responsible for replacing any damaged or unacceptable material at no cost to the owner.

All damaged rolls must be separated from the undamaged rolls until the proper disposition of the material has been determined.

ON-SITE STORAGE

Stored geomembrane shall be safely protected against puncture, dirt, grease, mud, excessive heat and other undesirable conditions.

Geomembrane rolls shall be stored on a prepared smooth surface (not wooden pallets), and shall not be stacked more than two high on soil subgrades. This requirement does not necessarily apply where a concrete pad or warehouse is available for storage purposes.

MATERIAL SPECIFICATION

Geomembrane Materials

The Geomembrane shall be high-density polyethylene (HDPE) with minimum thickness of 1.5 mm

The Properties of material shall be as follows:

Property

Test Method

Value

- Density gr/cc minimum

- Melt index gr/10Min, maximum

- Tensile Properties

Tensile strength at yield (pound/inch width)

Tensile strength at break (pound/inch width)

Elongation at yield (%)

Elongation at break (%)

- Tear resistance (Lbs)

- Puncture resistance (Lbs)

- Tensile Impact strength (Ft-lb/in²)

- Environtmental Stress Crack resistance (hours)

- Thermal stability oxidative induction time (OIT) Minutes

- Water absorption percent wt. Change (max)

ASTM D1505

ASTM D1238

ASTM D638

Type IV

ASTM D 1002

ASTM D 1822

ASTM D 746

Condition B

ASTM D 3895

200 ºC Pure O₂, 1 atm

ASTM D 570

0.944

1,0

144

300

800

381

2000

100

0.01

CONSTRUCTION

PREPARATION OF SUBGRADE

Prior to liner installation the subgrade shall be compacted in accordance with Maufacturer's Instruction or Requirements.

Weak or compressible areas which cannot be satisfactorily compacted should be removed and replaced with properly compacted fill. All surfaces to be lined shall be smooth, free of all foreign and organic material, sharp objects or debris of any kind.

The Subgrade shall provide a firm, unyielding foundation with no sharp changes or abrupt brakes in grade. Standing water or excessive moisture shall not be allowed.

VEGETATION CONTROL

The Contractor, if necessary or as described by the Owner, shall sterilize the area using an effective soil sterilant specially formulated for vegetation present in the area. The sterilant shall not be harmful to the liner and shall be applied according to the recommendation of its Geomembrane manufacture.

ANCHOR TRENCH

The anchor trench shall be excavated to the line, grade and width shown on the construction drawing, prior to the liner system placement. Slightly rounded corners shall be provided in the trench to avoid sharp bends in the Geomembrane.

METHOD OF PLACEMENT

The rolls shall be deployed using a spreader bar assembly attached to a loader bucket or by other methods approved by the Owner.

Equipment or Tools shall not damage the Geomembrane during handling, transportation and deployment.

Personal working on the Geomembrane shall not smoke or wear damaging shoes.

The method used to unroll the panels shall not cause scratches or crinips in the Geomembrane and shall not damage the supporting soil.

Adequate Loading e.g., shall be placed to prevent up lift by wind and continuous loading is recommended along edges of panels to minimize risk of wind flow under the panels

FIELD SEAMING

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

No base T-seam shall be closer than 1.5 m from the toe of the slope. Seams shall be aligned with the least possible number or wrinkles and "Fishmouth". If a fishmouth or wrinkle is found, it shall be relieved and cap-stripped.

SEAM OVERLAP

Geomembrane panels must have a finished minimum overlap of 10 cm or not shoe fusion welding and 7.5 cm inches for extrusion welding.

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

INSPECTION AND TEST

The Contractor shall be responsible for all inspection and testing works as required. The Owner may, during the course of the work, inspect the various phase of the work at the site, for full compliance with all requirement of this specification and drawing.

Any work failing to meet the specified requirements shall be rectified or replaced by the Contractor at this expense with no cost to the Owner.

FIELD SEAM TESTING

Field test seam 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.

PRE FABRICATED LINING POND WORKS

Value

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