Title: Specification, CQA Plan, and Installation Guide for fPP Pond Liners with Geocomposite Drainage Layer
Written by: I-CORP INTERNATIONAL
Date written: 1/10/02 Revised: 7/14/03

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1.0 INTRODUCTION

This document has been prepared for a 1 mm flexible polypropylene (fPP) liner with a geocomposite drainage and gas venting layer underneath.

The fPP geomembrane must be made with Basell CA743GA or CA 721GW natural resin with pre-compounded antioxidant additives. Carbon (N110) content should be nominally 2.75% but must be between 2.5 and 3.25%. Additional additives added by the geomembrane manufacturer to improve UV and thermal resistance of the geomembrane are allowed but they must be generically identified and it should be demonstrated to the Project Engineer using test data that improvements are achieved.

The geomembrane will be underlain by a double-sided geotextile/geonet composite (geocomposite) for both leakage collection/drainage, and for trapped air and biogas venting. At operating head the maximum allowable leakage flow rate shall be 100 gpad (1000 lphd). Leakage shall be recirculated into the pond.

The following specifications, installation guidelines, and CQA Plan should clarify to all parties the requirements of the Owner, so that all parties are on a level playing field. If there are any concerns they should be addressed to the Owner or Project Engineer for resolution before the installation starts.

2.0 PARTIES INVOLVED

2.1 Geomembrane Manufacturer

The Manufacturer shall be able to provide sufficient production capacity and qualified personnel to meet the demands of the project.

The Manufacturer shall be pre-qualified and approved by the Engineer and the Owner. The qualifications presented by the Manufacturer will, as a minimum, include:

• Corporate background and information

• Manufacturing capabilities:

• A list of at least 5 completed projects (and contacts) totaling a minimum area of 1,000,000 m², for which the Manufacturer has manufactured PP geomembrane materials from the same type of PP resin as that proposed to be used for this project.

2.2 Geomembrane Fabricator

The Fabricator shall meet the same requirements as the manufacturer.

2.3 Geomembrane Installer

The Installer will be trained and qualified to install PP geomembranes.

The Installer will be approved and/or licensed by the Manufacturer. A copy of the approval letter or license will be submitted by the Installer to the Project Manager.

Prior to confirmation of any contractual agreements, the Geomembrane Installer will provide the Project Manager with the following written information:

• Corporate background and information

• Installation capabilities:

. information on equipment and personnel,
. anticipated daily production,
. quality control manual for installation,
. samples of field seams and certified test results,
. written confirmation that all design features, Project Specifications, and requirements of the CQA Plan can be complied with.

• A list of at least 5 completed facilities (and contacts) totaling a minimum area of 500,000 m², for which the Installer has installed PP geomembrane

All personnel performing seaming operations will be qualified by experience. At least one seamer per crew will have experience seaming a minimum of 50,000 m of seams using the same method of seaming proposed for use on this project. The most experienced seamer, the "Master Seamer", will provide direct supervision, as required, over less experienced seamers. The Master Seamer, or his designate with equivalent experience, will be on site whenever seaming is being performed.

The Installer will provide the Project Manager with a list of proposed seaming personnel and their professional records. This document will be reviewed by the Project Manager and the CQA Consultant. Any proposed seaming personnel deemed insufficiently experienced will not be accepted by the Project Manager or will be requested to pass a seaming test.

The Installer will designate one representative as his Site Supervisor who will represent the Installer at all site meetings and be responsible for acting as the Installer's spokesman on site. The Supervisor will be qualified by experience. The Supervisor must have supervised the installation of a minimum of 300,000 m² of PP geomembrane. He will also exhibit good management and communications skills. His appointment will be approved by the Project Manager.

The Installer will also designate one representative with responsibility for Quality Control and signing all QC documents.

2.4 Transporter

All personnel responsible for the loading, transporting, and unloading of the PP geosynthetics must be fully aware of the consequences of damage to the materials, and must be familiar with handling and transportation constraints required by the Manufacturer. The Transporter will ensure that all rolls are shipped on trailers that can be accessed from the side for safe unloading. The decks of the trailers shall be visually inspected for exposed nails by the Manufacturer before loading. Any such nails shall be removed.

2.5 Construction Quality Assurance Consultant

The CQA Consultant will be experienced with PP geomembranes and be knowledgeable of PP geomembrane and seam performance characteristics. The CQA Consultant will be experienced in the preparation of CQA documentation including CQA manuals, forms, reports, and certifications.

The CQA Consultant will provide the following, in writing, to the Owner:

• Corporate background and information.

• A summary of the firm's experience in CQA of PP geomembranes, including a list of at least 3 completed facilities (and contacts) totalling a minimum of 100,000 m² in area, for which the CQA Consultant has provided CQA services.

• CQA forms used by the firm,

• Quality control manual or a summary of quality control practices.

2.6 Construction Quality Assurance Laboratory

The CQA Laboratory will have experience in testing PP geomembranes and seams and be familiar with ASTM, GRI, and other applicable test standards. The CQA Laboratory will be capable of providing test results within 6 hours of receipt of seam samples and will maintain that standard throughout the project. The laboratory shall be accredited by GAI-LAP (or other national accreditation organization) for those tests included in the Project Specifications and this CQA Plan. The CQA Laboratory shall be approved by the CQA Consultant and the Owner/Project Manager.

2.7 Duties of Construction Quality Assurance Personnel

The personnel of the CQA Consultant include:

• The CQA Manager, who operates from the office of the CQA Consultant and visits the site as required;

• The CQA Site Superintendent, who is located at the site; and

• The CQA Monitor(s), if any, who is (are) located at the site.

The duties of the CQA Personnel are discussed in the following subsections.

2.8 CQA Manager

The CQA Manager:

• reviews all designs, plans, specifications, QC programs, and the CQA Plan;

• reviews all other site-specific documentation, including bid documents, proposed panel layouts, and the geomembrane manufacturer and installer literature, for correctness, constructibility, level of quality and potential conflicts.

• attends the preconstruction meeting;

• ensures that the Manufacturer and Installer have reviewed, and can comply with, the Project Specifications and the CQA Plan;

• administers the CQA program, i.e., assigns and manages all CQA personnel, reviews all field reports, and provides engineering review of all CQA-related issues;

• provides quality control of the CQA personnel, including making site visits;

• reviews all changes to the design, plans, specifications, and installation procedures;

• proactively recommends quality improvements to the Project Manager within project budget constraints; and

• with the CQA Site Superintendent, reviews the record drawings and prepares the final report.

2.9 CQA Site Superintendent

The CQA Site Superintendent:

• acts as the on-site (resident) representative of the CQA Consultant;

• familiarizes all CQA Monitors with the site, the CQA requirements, and health and safety requirements for the project;

• manages the daily activities of the CQA Monitor(s);

• attends all CQA-related meetings (e.g., Resolution, Preconstruction, daily, weekly);

• verifies the calibration and condition of on-site testing equipment;

• reviews all CQA Monitors' daily reports and logs;

• reports to the Project Manager, and logs in his daily report, any relevant observations reported to him by the CQA Monitors;

• prepares his/her own daily report;

• assigns locations for testing and sampling;

• oversees the collection and shipping of all laboratory test samples;

• reviews results of laboratory testing and makes appropriate recommendations;

• reports any unresolved deviations from the CQA Plan to the Project Manager;

• prepares or oversees the ongoing preparation of the Record Drawings; and

• assists with the preparation of the final report.

The CQA Site Superintendent also:

• reviews all Supplier, Manufacturer, and Installer certifications and documentation, and makes appropriate recommendations;

• reviews the Installer's personnel qualifications for conformance with those pre-approved for work on-site;

• ensures that the Manufacturer and Installer have reviewed and can comply with the Project Specifications and the CQA Plan.

• notes, and reports to the Project Manager, any on-site activities that could result in damage to the geomembranes and other geosynthetics.

• makes recommendations for improvements in the liner quality; and
• contributes to the solution of all geosynthetic problems.

3. COMMUNICATIONS

All formal communications between the CQA Consultant and Owner will be in writing between the CQA Manager and the Project Manager. The CQA Site Superintendent may initiate such communications but they will eventually require the CQA Manager's signature.

The CQA Site Superintendent is expected to maintain informal communications with other on-site staff of project parties but will not issue direct instructions to them. The CQA Site Superintendent, with the CQA Manager's approval, will present CQA team proposals and supporting arguments to the Project Manager who will make the final decisions.

All formal communications between parties to the project will pass through the Project Manager unless otherwise approved by the Project Manager.
If, in the interests of time and technical understanding, informal communications occur between two parties along separate administrative paths (e.g. between CQA Consultant and Resin Supplier) such communications shall also be copied to the Project Manager.

Under no circumstance will CQA staff or any other project party disclose project related information to strangers on the site. It is recommended that the Owner issue distinctive badges to all project personnel in order that strangers can be identified.

Speed and permanent records will be the essence of all communications.

4. UNITS

In this CQA Plan, all properties and dimensions are expressed in SI units. If the manufacturer, fabricator, or installer presents information or data in US units, the SI units in this plan shall be deemed to govern. It should be noted that the conversion is typically only accurate to within ten percent (10%).

5. PROJECT CONTROL: ACTIVITIES, SCHEDULE, AND PROBLEM SOLUTION

5.1 Project Coordination Meetings

To guarantee high quality and smooth workflow during installation, clear, open channels of communication are essential. To that end, meetings are critical.

5.1.1 Resolution Meeting

Following the completion of the design, plans, specifications, and this CQA Plan for the project, a Resolution meeting will be held. This meeting will include all parties then involved, including the CQA Manager, the Project Manager, the Engineer, the General Contractor, and the Installer.

The purpose of this meeting is to begin planning for coordination of tasks, to anticipate any problems which might cause difficulties and delays in construction, and, above all, to present the CQA Plan to all of the parties involved. It is very important that the procedures regarding testing, repair, etc., be known and accepted by all. This site specific CQA Plan may be amended at the Resolution Meeting, after review by the CQA Consultant.

The first part of the Resolution Meeting may be devoted to a review of the design drawings and specifications. This is different from the peer review of the design, including design calculations, which would have been carried out previously.

This meeting should include all of the following activities:

• review critical design details of the project;

• review the Project Specifications;

• review the CQA Plan;

• review the Manufacturer's and Installer's QC Programs for compatibility with other project documents.

• review the panel layout drawing;

• make appropriate modifications to the CQA Plan to ensure that it identifies all necessary CQA;

• make appropriate modifications to documents to ensure their integration and compatibility;

• reach a consensus on the CQA and quality control procedures, especially on methods of determining acceptability of the PP geomembrane;

• assign the responsibilities of each party;

• decide the number of geomembrane seaming units to be maintained on-site by the Installer (this number depends on the number of seaming crews and on the type of seaming equipment);

• establish work area security and health and safety protocols;

• confirm location of nearest medical centre, hospital, and police station;

• confirm the methods for documenting and reporting data, and for distributing documents and reports; and

• confirm the lines of authority and communication.

The meeting will be chaired by the Project Manager and will be documented by a person designated at the beginning of the meeting, or by the CQA Consultant. Minutes will be transmitted to all parties by fax or email within 48 hours, and will be edited and returned to the Project Manager within a further 24 hours.

5.1.2 Pre-Construction Meeting

A Pre-Construction Meeting will be held at the site. At a minimum, the meeting will be attended by the Project Manager, the CQA Site Superintendent, the General Contractor, and the Installer. The meeting will be chaired by the Project Manager or designate.

Specific requirements for this meeting are to:

• make any final modifications to the CQA Plan;

• review the project specifications;

• review the responsibilities of each party;

• review and confirm lines of authority and communication;

• review methods, forms and routing for documents and reports;

• establish protocols for sampling and testing;

• establish protocols for handling deficiencies, repairs, and retesting;

• review the schedule for all operations;

• establish rules for writing on the geomembrane, i.e., who is authorized to write, what can be written, and in which color;

• outline procedures for packaging and storing archive samples;

• review panel layout and numbering systems for panels and seams;

• establish procedures for use of the seaming equipment;

• finalize field cut-out sample sizes;

• review qualifications of CQA Independent Laboratory;

• review repair procedures;

• review procedures for compensation allowance, treatment of wrinkles, and obtaining intimate contact between geomembrane and subgrade;

• review activities and responsibilities associated with maintaining, dewatering, and filling the anchor trench;

• consider environmental problems that could occur (excessive wind, rain etc.) and associated remedial activities;

• conduct a site walk-around to verify that earthwork construction is proceeding on schedule, and to review material storage locations, and

The meeting will be chaired by the Project Manager and will be documented by a person designated at the beginning of the meeting. Minutes will be transmitted to all parties within 24 hours, for approval and signature within a further 24 hours.

5.1.3 Progress Meetings

A weekly progress meeting will be held between the Project Manager and the CQA Site Superintendent, the Installer, the General Contractor, and any other concerned parties. The meeting will be chaired by the Project Manager or designate. Minutes will be recorded by the Project Manager or designate. This meeting will discuss current progress, planned activities, revisions to the work, and any new business. The CQA Site Superintendent will log any problems, decisions, or questions arising at this meeting in his/her daily reports. Any matter requiring action which is raised in this meeting will be reported to the appropriate parties. Minutes of the meeting will be circulated to all parties within 24 hours. Corrections must be made and submitted to the Project Manager within a further 24 hours.

5.1.4 Action Decision Meeting

This special meeting will be held when, and if, a problem or deficiency has occurred, or is likely to occur, that requires special action decisions by several parties. The meeting will be attended by the Project Manager, the CQA Site Superintendent, the Installer and other involved parties. If the problem requires a design modification, the Design Engineer should also be present. The purpose of the meeting is to define and resolve the problem or work deficiency as follows:

• Define the problem or deficiency;

• Establish the cause;

• Define possible solutions;

• Select a suitable technical solution agreeable to all parties

• Define an action plan to implement the solution; and

• Identify the party responsible for implementing the solution.

The meeting will be chaired by the Project Manager and documented by a person designated at the meeting. Minutes will be transmitted to affected parties within 24 hours. Corrections must be made and submitted to the Project Manager within a further 24 hours.

5.2 Project Control Visits

Periodically, the construction site may be visited by the CQA Manager. This visit should, if necessary, be coordinated with a similar visit by the Project Manager.

6. GEOMEMBRANE MANUFACTURING, TRANSPORTATION, AND STORAGE

6.1 Polypropylene Geomembrane Manufacturing

The fPP geomembrane must be made with Basell CA743GA or CA721GW PP natural resin with antioxidant additives. Carbon (N110) content should be nominally 2.75% but must be between 2.5 and 3.0%. Additional additives added by the geomembrane manufacturer to improve UV and thermal resistance of the geomembrane are allowed but they must be identified and it should be demonstrated to the Project engineer using test results that improvements are achieved. Geomembrane rolls may be prefabricated into larger panels to minimize field seaming.

6.1.1 Raw Material

The raw material will be first quality PP resin containing no more than 5% clean post-industrial (edge trim) recycled polymer by weight.

Quality Control Certificates will be provided for all resin used to manufacture the geomembrane.

6.2 Quality Control

The Manufacturer and Fabricator shall make available to the Owner and CQA Consultant Manufacturing Quality Control manuals which outline all quality procedures which will be implemented for the manufacture of the PP geomembranes.

6.3 Manufacturing

6.3.1 Submittals

Prior to the installation of any geomembrane, the Manufacturer will provide the Project Manager and the CQA Consultant with the following:

• A certified properties sheet including, at a minimum, all specified properties, and test methods indicated in the specifications;

• A list of quantities and descriptions of materials other than the base polymer which comprise the geomembrane; and

• The internal MQC sampling procedures, frequencies of testing, and results of testing of material supplied to the project.

The CQA Consultant will verify that:

• the property values certified by the Manufacturer meet all of the Manufacturer's specifications; and

• the measurements of properties by the Manufacturer are properly documented, the test methods used are acceptable, and the geomembrane meets the Project Specifications.

6.3.2 Rolls

Prior to shipment, the Manufacturer will provide the Project Manager and the CQA Consultant with Quality Control certificates covering each roll of geomembrane and welding rod provided. The Quality Control certificate will be signed by a responsible party employed by the Manufacturer, preferably the QC Laboratory Manager. The Quality Control certificates will include:

• resin Manufacturer, resin type, resin lot number, and geomembrane roll numbers; and

• results of Quality Control tests. At a minimum, results will be given for thickness, specific gravity/density, uniaxial tensile strength and elongation at break and carbon black content and dispersion, evaluated in accordance with the methods indicated in the specifications or equivalent methods previously approved by the Project Manager and CQA Consultant. No material will be installed until complete QC test data have been provided.

The CQA Consultant will:

• verify that the Quality Control certificates have been provided at the specified frequency for all rolls, and that each certificate identifies the rolls and resin related to it; and

• review the Quality Control certificates and verify that the certified roll properties meet the Manufacturer's and Project Specifications.

6.3.3 Fabrication

The geomembrane may be prefabricated under controlled conditions into larger panels to minimize the number of field seams. These panels will be up to approximately 2,500 m² (25,000 ft²) in area.

Each panel will be given an identifying number and a log will be kept of all roll numbers used to fabricate that panel.

The seams may be made by dielectric welding equipment or thermal fusion equipment. They may be dual track seams with a center air channel for air pressure testing (see Section 8.3.8.4) or they may be single track seams a minimum of 25 mm wide bonded to the edge of the top sheet.

All factory seams will be nondestructively tested along their full length using the air pressure test on the double track seams or the air lance test on single track seams.

The air lance shall have a nozzle approximately 4.5 mm in diameter and deliver air to the edge of the seam at a pressure of about 380 kPa (55 psi) from a distance of about 10 mm.

On each panel at least one seam will be made a little longer than normal so that a sample can be removed for destructive testing (see Section 8.6). The destructive test sample shall not be made by running separate pieces of material through the welder.

Throughout the fabrication process the surfaces of the panels shall be visually examined for flaws and defects. Any such flaws and defects shall be repaired (Section 8.7) before the panel is shipped. The location of each flaw/repair shall be recorded on a repair log and shipped to site with the QC documents for that panel. Any observed flaws/defects that could not be repaired prior to shipping shall clearly be identified on the log.

QC certificates for the resin used to make the geomembrane rolls, for the manufacturing of the rolls, and the fabrication of the panels, shall be sent to the Project Engineer before material arrives on site.

Panels shall be accordion folded and rolled on a rigid core for shipping. Accordion folding in two directions is not permitted.

6.3.4 General Note on Testing

Throughout this project, it is necessary that all non-passing test results be recorded on record logs and data sheets. It must be evident that failures have occurred and the actions required to correct the failures must be identified.

6.3.5 Conformance Testing

Conformance testing is not an opportunity to reproduce the QC testing program, but is simply a spot-check to provide confidence that satisfactory material is delivered to the site.

6.3.5.1 In-Plant testing

The purpose of in-plant material conformance test sampling is to verify that geomembrane material which is designated for the Owner's project is confirmed as meeting the project specifications prior to shipment to the site. Thus, barring a transportation accident, the geomembrane can be installed immediately it arrives on site.

The Manufacturer will make available all necessary personnel and equipment to assist the CQA Consultant in retrieving conformance samples of the geomembrane material.

The CQA Consultant shall send to the CQA Laboratory conformance samples for testing as outlined in Section 6.3.6. The frequency of sampling shall be at the discretion of the CQA consultant but shall typically be between each 10,000 and 25,000 m² of geomembrane. No material shall be shipped to the site until conformance test results are obtained.

The CQA Consultant shall report any nonconformance of sampling procedures as outlined in Section 6.3.10 to the Project Manager.

6.3.5.2 On-site material testing

If In-Plant conformance testing is not performed, upon delivery of the rolls of geomembrane to the site, the CQA Consultant will ensure that samples are removed at a frequency of at least 1 sample per 10,000 m² and forwarded to the CQA Laboratory for testing to ensure conformance to both the Project Specifications and the Manufacturer's list of guaranteed properties.

6.3.5.3 Properties of the PP Geomembrane

The PP geomembrane shall meet the specifications shown in Table 1.

TABLE 1. PP GEOMEMBRANE SPECIFICATIONS

6.3.6 Conformance Tests

At a minimum, tests to determine the following parameters will be performed on PP geomembranes:

• thickness;

• carbon black content and dispersion; and,

• uniaxial tensile break strength and elongation.

6.3.7 In-plant conformance sampling

In the interests of time, rolls may be sampled in the plant for conformance testing but without the CQA consultant being present.

A full roll width sample will be cut out by the manufacturer in a free-hand wavy pattern from the end of a roll and sent to the CQA laboratory for testing. At the conclusion of testing, the remaining sample material will be sent to the site so that the cut edge can be matched to the cut edge on the roll. Assuming passing test results the material can be used as soon as it arrives on site.

6.3.8 Sampling Procedures

Samples will be taken across the entire width of the roll and will not include the outer wrap of the roll. Unless otherwise specified, samples will be 500 mm long by the roll width. Specimens for testing will be taken across the full width of the sample.

If roll numbers are very different and non-sequential, consideration should be given to testing each block of roll numbers at the same frequency.

6.3.9 Test Results

The CQA Consultant will examine all results from laboratory conformance testing and will report any nonconformance to the Project Manager.

6.3.10 Procedures in the Case of a Conformance Test Failure

The following procedure will apply whenever a sample fails a conformance test that is conducted by the CQA Laboratory:

• The Manufacturer will replace the roll of geomembrane that is in nonconformance with the specifications with a roll that meets specifications.

• The CQA Site Superintendent will remove conformance samples for testing by the CQA Laboratory from the next higher and lower numbered rolls. These two samples must both conform to specifications. If either of these samples fail, testing shall continue until the defective rolls are isolated. These rolls will be replaced by the Manufacturer, at no expense to the Owner. This additional conformance testing will be at the expense of the Manufacturer.

The CQA Consultant will document actions taken in conjunction with conformance test failures.

6.4 Delivery

6.4.1 Transportation and Handling

Transportation of the geomembrane is the responsibility of the Manufacturer, Installer, or other party as agreed upon. All handling on-site is the responsibility of the Installer.

The CQA Consultant will verify that:

• handling equipment used on the site is adequate and does not pose any risk of damage to the geomembrane particularly to the edges of the geomembrane; and

• the Installer's personnel handle the geomembrane with care.

Upon delivery at the site, the Installer and the CQA Consultant will conduct a visual examination of all rolls for defects and signs of damage. This examination will be conducted without unrolling rolls unless defects or damage are found or suspected. The CQA Consultant will indicate to the Project Manager:

• any rolls, or portions thereof, which should be rejected and removed from the site because they have unacceptable flaws; and

• any rolls which contain minor repairable flaws.

6.4.2 Storage

The Installer will be responsible for the storage of the geomembrane on-site. The Project Manager will provide storage space in a location (or several locations) such that on-site transportation and handling are minimized. Geomembrane rolls will be stored on a smooth, dry, level surface in an area where the geomembrane, particularly the roll edge, is protected from damage. Rolls, particularly textured rolls, will not be allowed to get dirty.

The CQA Consultant will verify that storage of the geomembrane ensures adequate protection against dirt, impact, and other sources of damage.

Rolls will not be stored more than 3 high. Access will be provided to each end of stored rolls for the examination of identification labels and examination of roll edges.

Chocks to prevent rolling will be bevelled to avoid concentrated stresses on the geomembrane.

7.0 GEOCOMPOSITE

The double purpose leakage collection/drainage and gas venting layer shall be a biplanar or triplanar HDPE geonet with a nonwoven geotextile on each side, the upper one for increased friction with the underside of the geomembrane and the lower one to act as filter between the subgrade soil and the drainage layer.

Note: In double geomembrane lining systems, if an electrical integrity survey of the primary liner is required the upper geotextile of the geocomposite shall be electrically conductive.

7.1 Specifications and QC certificates

The geocomposite and its component parts shall meet the specifications shown in Table 2. The geonet strands shall not contain any fillers or voids.

TABLE 2. GEOCOMPOSITE SPECIFICATIONS

Parameter	Test Method	Minimum Average Values
Geocomposite
Transmissivity (m2/sec)	ASTM D4716-00(a)	1 x 10-4
Ply Adhesion (lb/in. minimum)	GRI GC-7	0.5
Ply Adhesion (lb/in. average)	GRI GC-7	1.0
Geonet core (prior to lamination)
Thickness (mm)	ASTM D5199	5
Transmissivity (m2/sec)	ASTM D4716-00(a)	2 x 10-3
Density (g/cm3 )	ASTM D1505	0.94
Tensile Strength (MD) (lb/in. (N/mm)	ASTM D5035	45 (7.9)
Carbon Black Content (%)	ASTM D1603	2.0 – 3.0
Geotextile (prior to lamination)
Mass (oz/yd2 g/m2)		8.0 (270)
Thickness (mil mm)	ASTM D5199	90 (2.2)
Grab Tensile (lb) (N)	ASTM D4632	220 (975)
Puncture Strength (lb) (N)	ASTM D4833	135 (600)
AOS, US sieve (mm)	ASTM D4751	80 (0.180)
Flow Rate (gpm/ft2)(lpm/m2)	ASTM D4491	110 (4480)

(a) Hydraulic Gradient 0.1, normal load 10 kPa

Prior to arrival of the geocomposite on-site the Installer shall provide the Project Engineer with signed quality control certificates from the manufacturers of the geotextiles, the geonet, and the fabricated geocomposite. A QC certificate for the HDPE resin used in the geonet shall also be provided.

7.2 Shipping and storage

The geocomposite shall be wrapped with untorn impermeable and opaque protective covers on arrival at the site and shall be stored on smooth, dry surfaces, and in such a way that if it rains the geonet will not be contaminated. Rolls will be stored no more than three high.

Each roll will be identified, on the cover, with the manufacturer’s name, the product type, the roll number, its width, its length, and its weight. Labels must be readable while the roll is in its stored location.

7.3 Conformance testing

One roll every 10,000 m² will be sampled across the full roll width for conformance testing at an independent GAI-LAP accredited geosynthetics testing laboratory (or other nationally recognized accreditation organization). More rolls may be sampled if roll numbers are not significantly sequential.

The following conformance tests will be performed:

• Geonet density (ASTM D1505)
• Geotextile/geonet ply adhesion (GRI.GC7)
• Geocomposite transmissivity (ASTM D4716)

Failing samples will result in that roll being set aside. The next higher and lower roll numbers will then be tested, and so on until the extent of the non conformance is defined. Any additional testing after the first roll, and costs to replace nonconforming rolls, will be to the account of the Installer.

7.4 Installation

Rolls will be handled with equipment that does not damage the geotextile or the geonet.

Rolls will be unrolled under controlled conditions (i.e. not allowed to unroll freely down slopes) and deployed material shall not be under stress.

Geocomposite will extend completely over all concrete pads at pipe penetrations. A geotextile strip will be placed over all cut edges of geonet to prevent the sharp edges from damaging the overlying geomembrane.

Seams will be oriented up and down slopes, not across slopes, and there shall be no seam closer than 3 m (10 ft) to the toe of any slope.

Care shall be taken not to contaminate and block the passageways in the geonet with soil. Any such soil shall be removed by the installer to the satisfaction of the CQA Superintendent.

Roll edges shall be overlapped about 150 mm (6 in). Butt joints at the ends of rolls shall be overlapped 300 mm (12 in). All roll end joints shall be shingled down slope.

The underside geotextiles at the edges of rolls shall be carefully fully overlapped without folding. The sides of the geonet rolls on the floor shall be fastened with plastic ties (not metal ties or staples) every 2 m (6 ft) and every 1 m (3 ft) on side slopes. In the anchor trench the geonet shall be fastened every 500 mm (20 in.). The top geotextiles shall also be fully overlapped and thermally bonded to prevent separation, extending to the edge of the geocomposite in the anchor trench.

At roll end overlaps the top geotextile of the bottom roll and the bottom geotextile of the top roll shall be removed to allow continuous drainage across the joint. A strip of geotextile at least 300 mm (12 in.) wide will be placed on the subgrade at the end of the lower roll to prevent soil accessing the end of the geonet. The geonet will be tied with plastic ties at least every 500 mm (20 in.).

Where there are two layers of geocomposite it shall be ensured that the strands of one layer do not penetrate the strands of the other layer and cause restrictions to flow.

All damaged geonet and geotextile will be repaired with patches of geotextile or geocomposite as appropriate. If damage exceeds half the width of a roll the damaged section of the roll shall be cut out and a full roll width joint made. Such joints will not be allowed on side slopes.

Only that amount of geocomposite shall be deployed each day that can be covered with geomembrane. As necessary, geocomposite rolls shall be ballasted with sand bags or other non-damaging weights to prevent displacement during reasonably foreseeable winds. Any exposed edges of geocomposite shall be covered and protected from mechanical damage and infiltration by soil.

7.5 Repairs

Repair patches shall overlap the damaged area by at least 500 mm (20 in.) in all directions. Geotextiles between geonet layers shall be removed to allow continuity of flow within the geonet layer. Edges of geonet exposed to soil shall be suitably covered by a layer of geotextile to preclude access of soil.

A strip of geotextile will be placed over the edge of cut geonet to protect the underside of the geomembrane from puncturing damage by sharp edges of the geonet.

Patches shall be fastened to the base geocomposite with plastic ties every 300 mm (12 in.) around the circumference on the floor of the lake and every 150 mm (6 in.) on the side slopes. Alternatively the two geotextiles shall be heat bonded together to prevent displacement of the patch. When the patch is first attached the top geotextile of the base geocomposite around the patch will be marked to indicate whether the patch has subsequently moved prior to placement of the geomembrane.

8. GEOMEMBRANE INSTALLATION

8.1 Earthwork

8.1.1 Surface Preparation

The Owner will be responsible for preparing the supporting soil according to the project specifications and the satisfaction of the Installer.

The CQA Consultant will verify that:

• a qualified Land Surveyor has established all lines and grades, and
they are approved by the Project Manager;

• the supporting soil meets the density specification;

• the surface to be lined has been finished so as to be free of
irregularities, protrusions, loose soil, desiccation cracks, and abrupt
changes in grade;

• the 50 mm surface layer of the supporting soil does not contain
stones or other objects which may be damaging to the geomembrane; and

• there are no areas excessively softened by high water content.

The Installer will certify in writing that the surface on which the geocomposite will be installed within the next 24 hr is acceptable. The certificate of acceptance will be given by the Installer to the Project Manager prior to commencement of geocomposite installation in the area under consideration. The CQA Consultant will be given a copy of this certificate by the Project Manager. The CQA Consultant will also acknowledge approval of the subgrade.

After the supporting soil has been accepted by the Installer, it will be the Installer's responsibility to indicate to the Project Manager any change in the supporting soil condition that may require repair work. If the CQA Consultant concurs with the Installer, then the Project Manager will ensure that the supporting soil is repaired.

8.1.2 Anchor Trenches

Anchor trenches will be excavated by the Owner (unless otherwise specified) to the lines and dimensions shown on the design drawings, prior to geomembrane placement. The CQA Consultant will verify that anchor trenches have been constructed according to the design
drawings.

The edge of the trench, over which the geocomposite geomembrane enter the trench, will be rounded to avoid sharp bends in the geomembrane. There shall be no sharp protrusions on the inside wall of the trench. No loose soil will be allowed to underlie the geomembrane in the trenches.

Water shall not be allowed to stand, or soften the soil, in the anchor trench. Responsibility for dewatering of the anchor trench shall be the Owner's. Backfilling of anchor trenches will be conducted in accordance with Section 8.8.

8.2 Geomembrane Placement

Before any geomembrane is deployed the documents listed in Appendix A must be received from the Installer and be reviewed and approved by the CQA Consultant and Project Manager.

8.2.1 Field Panel Identification

A field panel is a single piece of geomembrane (other than a patch or cap strip) which is seamed in the field: i.e. a roll or a portion of roll cut in the field.

It will be the responsibility of the CQA Site Superintendent to ensure that each field panel is given an "identification code" (number or letter-number) consistent with the layout plan. This identification code will be agreed upon by the Project Manager, Installer, and CQA Consultant.
This field panel identification code should be as simple and logical as possible. It will be the responsibility of the Installer to ensure that each field panel placed is also marked with the original roll number. The identification code and roll number will be marked at a location agreed upon by the Project Manager, Installer, and CQA Consultant.

Typically, panels will be numbered in the order in which they are placed. The CQA Site Superintendent will establish a table or chart showing correspondence between roll numbers and field panel identification codes. The field panel identification code will be used for all CQA records.

8.2.2 Field Panel Placement

No geosynthetics shall be deployed, joined, or tested unless a representative of the CQA Consultant is present to monitor such activities.

8.2.2.1 Compensation for Material Expansion and Contraction

The Installer will be responsible for ensuring that the geomembrane is installed in such a way as to minimize problems with wrinkles, particularly at the toes of slopes. The geomembrane must not be tensioned and must be installed in such a way as to be fully supported by the subgrade as it is covered by water.

At all times the exposed edges of geosynthetics will be kept clean and protected from damage.

8.2.2.2 Installation Schedule

Field panels will be placed one at a time, and each field panel will be seamed immediately after its placement (in order to minimize the number of unseamed field panels exposed to wind).

It is beneficial to "shingle" overlaps in the downslope direction to facilitate drainage in the event of precipitation, shingling should also be done in the downstream direction to minimize resistance to flow. It is also beneficial to proceed downslope and in the direction of (with) prevailing winds. Scheduling decisions must be made during installation, in accordance with varying environmental conditions. In any event, the Installer will be fully responsible for the decisions made regarding placement procedures.

The CQA Consultant will evaluate every change in the schedule proposed by the Installer and advise the Project Manager on the acceptability of that change. The CQA Consultant will verify that the condition of the supporting soil is still satisfactory for installation of geocomposite.

The CQA Consultant will record the identification code, roll number, location, weather conditions, and date of installation of each field panel.

8.2.2.3 Weather Conditions

Geomembrane seaming will not proceed at geomembrane temperatures above 80°C unless approved by the Project Manager. Approval will not be unreasonably withheld provided the Installer can demonstrate the ability to produce satisfactory seams. The frequency of trial seams (Section 8.3.6), or seam destructive test sampling, (Section 8.6.3) may be increased at extreme geomembrane temperatures (>80°C). Geomembrane placement will not be done during any precipitation, in an area of ponded water, or during excessive winds except as approved by the CQA by the CQA Superintendent.

NOTE: The only temperature of significance is the actual geomembrane temperature, not the ambient temperature.

The CQA Consultant will verify that the above conditions are observed. Additionally, the CQA Consultant will verify that the supporting soil has not been damaged by weather conditions.

The CQA Site Superintendent will inform the Project Manager if the above requirements are not observed.

8.2.2.4 Geomembrane Placement

The CQA Consultant will verify that:

• equipment used does not damage the geomembrane as a result of handling, trafficking, excessive heat, leakage of hydrocarbons, or by other means;

• any All-Terrain Vehicles (ATVs) used to deploy geosynthetics exert ground pressures less than 55 kPa (8 psi).

• ATVs are not operated: 1) at excessive speeds, 2) in tight turning circles, 3) under extreme breaking and accelerating conditions, 4) with dirty tires, and 5) over wrinkles, that might damage the geomembrane.

• the prepared surface underlying the geocomposite has not deteriorated since previous acceptance, and is still acceptable immediately prior to geocomposite placement;

• any geosynthetic elements immediately underlying the geomembrane are clean and free of debris;

• personnel working on the geomembrane do not smoke, do not wear hard-soled shoes, and do not engage in activities which could damage the geomembrane;

• frequently used pathways up and down geomembrane on slopes are protected;

• the methods used to unroll geocomposite and geomembrane panels do not cause excessive scratches or crimps in the geomembrane and do not damage the supporting soil;

• the method used to place the panels minimizes wrinkles (especially differential wrinkles between adjacent panels);

• geomembrane is not allowed to unroll freely down a slope;

• geomembrane is not placed under tension, unless approved by the Project Manager;

• direct contact of equipment with the geomembrane shall not be allowed, except as previously described for ATVs used to deploy geosynthetics. The geomembrane shall be protected by geotextiles, extra geomembrane, soil layers, or suitable materials, in areas where equipment may be used or traffic may be expected;

• only hook-blade utility knives are used to cut through the geomembrane.

• appropriate care is to be taken to prevent shock and explosions caused by static electricity discharges.

• all handholds cut for moving panels and damage caused by clamps are repaired;

• panels are not moved such that subgrade geosynthetics can peel the underside seam flap or that the seam flap will separate geotextile overlaps/joints.

The CQA Site Superintendent will inform the Project Manager if the above requirements are not observed.

8.2.2.5 Temporary Ballasting

Temporary ballasting around the edges of the installed liner shall be done with sandbags or equivalent non-damaging ballast material (e.g. tires without reinforcing wires exposed). Sandbags shall be handleable by one person. Ballast shall be placed to provide adequate uplift protection against typical winds that might reasonably be expected to occur prior to the addition of adjacent panels or prior to permanent ballasting.

8.2.2.6 Damage

The CQA Consultant will visually examine each panel, after placement and prior to seaming, for damage. The CQA Site Superintendent will advise the Project Manager which panels, or portions of panels, should be rejected or repaired. Damaged panels or portions of damaged panels, which have been rejected will be marked, and their removal from the work area recorded by the CQA Consultant. Repairs will be made according to procedures described in Section 8.7.3.

At a minimum, the CQA Consultant will ensure that:

• each panel is placed in such a manner that it has not been, or is unlikely to be, damaged; and

• any tears, punctures, holes, thin spots, and damaging inclusions, gouges, and protuberances etc., are marked for repair, or the panel is rejected.

8.3 Field Seaming

8.3.1 Seam Layout

Prior to the commencement of installation activities the Installer will provide the Project Manager and the CQA Consultant with a proposed panel layout drawing. The CQA Consultant will review the panel layout drawing and verify that it is consistent with the accepted state-of-practice and this CQA Plan. No panels may be seamed in the field without the CQA Superintendent's approval. In addition, panels that significantly change the layout drawing, (e.g. that change the orientation of seams) shall not be installed without the CQA Superintendent's prior approval. It is, however, recognized that such a drawing is only a guide and will, in practice, require modification.

In general, seams should be oriented parallel to the line of maximum slope, i.e., oriented up and down, not across, the slope. In corners and other geometrically complex locations, the number of seams should be minimized. No base seam or tee seam will be less than 2 m from the toe of slopes, or areas of potential stress concentrations, unless otherwise authorized by the Project Manager.

Horizontal roll end seams are not allowed on slopes.

Seams will be identified by the panel numbers on each side, e.g. Seam 1 / 2, for the seam between panels 1 and 2.

8.3.2 Seaming Equipment and Products

Approved methods for field seaming are thermal fusion (hot wedge, hot air, or combination) seaming and extrusion seaming. Proposed alternate methods will be documented and submitted to the Project Manager and CQA Consultant for approval. Only apparatus that has been specifically approved by make and model will be used. The Installer will use appropriate measuring equipment to ensure that required temperatures are being achieved.

Fusion seams shall be double track seams suitable for center channel air-pressure testing, or single track seams a minimum of 25 mm wide that will be tested with an airlance.

8.3.2.1 Fusion Seaming

Fusion seaming must be done with automated self-propelled machines. The fusion seaming machines will be equipped with gauges giving hot wedge temperatures. Temperature, speed, and nip roll pressure settings will be verified by the Installer prior to each seaming period. Nip roll and wedge geometries shall be such as to minimize residual stresses at the edge of the seam.

The CQA Consultant will log ambient conditions, geomembrane temperatures, seaming apparatus temperatures and speeds, equipment serial number, and operator initials.

The CQA Consultant will also verify that:

• the Installer maintains on-site an adequate number of operable seaming machines;

• equipment used for seaming does not damage the geomembrane;

• for tee seam intersections, all edge flaps are cut back to the edge of the outer-most peel-tested track of the seam prior to seaming;

• electric generators and fuel containers are placed on a smooth protective layer such that no damage occurs to the geomembrane;

• a smooth insulating plate or fabric is placed beneath the hot seaming apparatus after usage;

• the geomembrane is protected from damage in heavily-trafficked areas; and

• build-up of moisture between the sheets is prevented. To accomplish this a movable protective layer may be used directly below each overlap of geomembrane that is to be seamed.

8.3.2.2 Extrusion Seaming

Extrusion-seaming apparatus will be equipped with gauges giving the relevant temperatures of the apparatus such as the temperatures of the extrudate, nozzle, and preheat air.

The Installer will provide documentation (including QC certificates) regarding the welding rod or resin pellets to the Project Manager and the CQA Consultant, that show that the resin is the same PP resin as the geomembrane itself. Other seaming resins must be approved by the Project Manager and the CQA Consultant.

The CQA Consultant will log apparatus temperatures, extrudate temperatures, ambient conditions, and geomembrane temperatures at appropriate intervals.

The CQA Consultant will verify that:

• the Installer maintains on-site an adequate number of operable seaming machines;

• equipment used for seaming will not damage the geomembrane;

• the extruder is purged prior to seaming until all heat-degraded extrudate has been removed from the barrel;

• feed resin is maintained clean and dry;

• the electric generator and fuel containers are placed on a smooth intermediate layer such that no damage occurs to the geomembrane;

• a smooth insulating plate or fabric is placed beneath the hot seaming apparatus after usage; and

• the geomembrane is protected from damage in heavily trafficked areas.

8.3.3 Seam Preparation

The CQA Consultant will verify that:

• prior to seaming, the seam area is clean and free of moisture, dust, dirt, debris of any kind, foreign material, and any mechanical damage;

• if seam overlap grinding is required, the process is completed according to the Manufacturer's instructions but within 30 minutes of the seaming operation, and in a way that does not damage the geomembrane;

• the abrading does not remove more than 10 percent of the thickness of the geomembrane, and the resulting abrasion marks are covered by the finished extrusion bead;

• any visible abrasion marks, after seaming, are essentially perpendicular to the direction of the seam;

• the abrading does not introduce damaging gouges in the geomembrane; and

• seams/panels are aligned with a minimum of wrinkles and "fishmouths".

8.3.4 Weather Conditions for Seaming

The following protocols will be observed during seaming:

• Unless authorized in writing by the Project Manager, no seaming will be attempted at geomembrane temperatures above 80°C.

• In all cases, the geomembrane in the seaming area will be dry and protected from wind and airborne particulates.

• Geomembrane temperatures will be measured with a surface temperature thermocouple or a calibrated infrared pyrometer.

If the Installer wishes to use methods which may allow seaming at geomembrane temperatures above 80°C, the Installer will demonstrate (by testing trial seams) that such methods produce seams which are entirely equivalent to seams produced at geomembrane temperatures below 80°C, and that the overall quality of the seam and durability of the geomembrane are not adversely affected. In addition, the Installer will prepare written certification that states that the seaming procedure does not cause any physical or mechanical modification to the geomembrane that will generate any short or long-term damage to the geomembrane liner.
The CQA Consultant will verify that these requirements are observed and will advise the Project Manager if potential problems are perceived. The Project Manager will then decide if the seaming will be stopped or postponed. Such decisions may be the subject of an Action Decision Meeting.

8.3.5 Overlapping and Temporary Bonding

The CQA Consultant will verify that:

• the panels of geomembrane have an overlap of approximately 100 mm, sufficient to allow peel tests to be performed on the inner track of the seam;

• there is a free flap at the edge of the top geomembrane a minimum of approximately 10 mm wide, to allow a peel test to be performed on the outer track of the seam. Typically there will be no free flap or single track welds;

• any procedure used to temporarily bond adjacent panels together does not damage the geomembrane. In particular, the temperature of hot air at the nozzle of any spot seaming apparatus will be controlled such that the geomembrane is not damaged. "Damage" includes a loss in durability; and

• temporary bonds do not interfere with the ability to perform shear and peel tests on the actual production seam.

The CQA Consultant will log all relevant temperatures and conditions, and will log and report any non-compliance to the Project Manager.

If protective layers of geomembrane are placed on the barrier layer geomembrane for any purpose (e.g. puncture protection in drainage trenches), they shall not be tack or spot welded to the barrier layer. They shall be fully welded, except for a small pressure relief segment, along the complete periphery of the protective layer or they shall not be welded at all.

8.3.6 Trial Seams

Trial seams will be made by each machine/operator combination on strips of PP geomembrane to verify that seaming can be successfully performed. Such trial seams will be made at the beginning of each seaming period (at least once every four hours), for each seaming apparatus/operator combination used in the seaming period. In addition, a new trial seam will be conducted when a welding apparatus has been restarted after being switched off.

A trial seam will also be made in the event that the geomembrane temperature changes more than 25°C since the last passing trial seam. Trial seams will be made under the same conditions as production seams will be made (e.g. on slopes if production seams are to be made on slopes). When geomembrane temperatures are higher than 80°C more frequent trial seams may be required.

The trial seam sample will be at least 1.5 m long by 0.3 m wide with the seam centered lengthwise.

Four specimens, each 25 mm wide and a minimum of 150 mm long, will be cut from the center section of the trial seam sample by the Installer. Two specimens will be tested in shear and two in peel using a calibrated field tensiometer. They should meet project specifications. If any specimen fails, the entire operation will be repeated. If the second trial seam fails, the seaming apparatus and seamer will not be approved for production seaming until the deficiencies are corrected and two consecutive successful trial seams are achieved.

The remainder of the successful trial seam sample will be assigned a number and marked accordingly by the CQA Consultant, who will also log the date, time, geomembrane temperature, number of seaming unit, settings, name of seamer, and pass or fail description. The remainder of the sample will be cut into two pieces, one each to be retained by the Owner, and Installer.

A trial seam shall also be prepared by each seaming machine/operator at the completion of seaming each day to determine whether changes in seam quality might have occurred during the last part of the seaming period.

Alternatively, a seam destructive sample could be required at the end of the last seam of the day.

The CQA Consultant will observe all trial seam procedures.

8.3.7 General Seaming Procedure

Unless otherwise specified, the general seaming procedure used by the Installer will be as follows:

• For fusion seaming, a movable protective layer of plastic may be placed directly below each overlap of geomembrane that is to be seamed. This is to help prevent any moisture build-up between the sheets to be seamed.

•If required, a firm substrate may be provided by using a flat board, or other similar hard surface placed directly under the seam overlap.

• Care shall be taken during extrusion and hot air seaming that the underlying geotextile is not melted.

• Fishmouths or wrinkles at the seam overlaps will be cut along the peak of the wrinkle in order to achieve a flat overlap. The cut fishmouths or wrinkles will be seamed and any portion where the overlap is inadequate will then be patched with an oval or round patch of the same geomembrane material extending a minimum of 150 mm beyond the cut in all directions. The end of the cut should be rounded.

• If seaming operations are carried out at night, adequate illumination will be provided.

• Seaming will extend to the outside edge of panels placed in the anchor trench.

• Each seam will be labeled with the seaming machine number, the operator's initials, machine temperature and speed settings, date, time, and direction seamed.

The CQA Consultant will monitor the above seaming procedures, and will inform the Project Manager of any unsatisfactory deviations from standard practice.

8.3.8 Nondestructive Seam Continuity Testing

8.3.8.1 Concept

The Installer will nondestructively test all field seams over their full length using a vacuum test unit, air pressure test (for double fusion seams only), spark test, or other approved method. Vacuum testing, air pressure testing, and spark testing are described in Sections 8.3.8.3, 8.3.8.4, and 8.3.8.5 respectively). The purpose of nondestructive testing is to check the continuity of seams. It does not provide any information on seam strength. Continuity testing will be carried out as the seaming work progresses, not at the completion of all field seaming. Nondestructive testing will not be permitted unless there is, in the opinion of the CQA Consultant, adequate illumination.

The CQA Consultant will:

• observe all nondestructive testing;

• record location, date, test unit number, operator, and outcome of all testing; and

• log and inform the Installer and Project Manager of any required repairs.

The Installer will complete any required repairs in accordance with Section 8.4.

The CQA Consultant will:

• observe the repair and re-testing of the repair;

• mark on the geomembrane that the repair has been successfully made and tested; and

• document the results.

The following procedures will apply to segments of seams that cannot be nondestructively tested:

• All such seam segments will be very carefully prepared and welded by the master seamer
under the observation of the consultant, or

• If the seam is accessible to testing equipment prior to final installation (e.g. after prefabrication), the seam will be nondestructively tested prior to final installation. For instance, prefabricated pipe boot seams can be tested hydrostatically.

• The seaming and testing opera