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4.5. Repair guidelines

4.5.1. Introduction

Even with periodic inspection and maintenance, lining systems will require repair from time to time. Although geomembrane

repair is typically conducted as a response to some type of damage to the pond, a pro-active approach to geomembrane

repair and renovation can improve the performance and extend the service life of the liner. The procedures and specifications

contained in this section provide valuable general information about the efficient and effective repair of Firestone EPDM lining

systems.

These guidelines apply to repairs to the Firestone EPDM Geomembrane (cuts and punctures in the EPDM geomembrane,

contamination of the EPDM geomembrane with hazardous products) and the field seams (wrinkles in a splice, QuickSeam

Splice Tape is not showing, QuickSeam Splice Tape is showing more than 25 mm, seam is showing possible water entry points).

These repair procedures are offered as a complementary service only, and Firestone disclaims any liability, under any theory

of law, arising from the use of these procedures. Repairs and renovations of Firestone EPDM lining systems should only be

performed by a professional lining contractor who is licensed and trained by Firestone.

4.5.2. Repair of cuts and punctures on the EPDM geomembrane

As soon as any damage to Firestone EPDM Geomembrane is identified (during installation or inspection), mark the damaged

area with a white crayon for use on rubber. The repair must extend a minimum of 75 mm beyond the perimeters of the

damaged area in all directions in case of repairs using Firestone QuickSeam products and 100 mm in case of repair using

Firestone EPDM Geomembrane. Round all corners of the repair piece.

• Pinholes and small punctures in the EPDM geomembrane may be repaired with a cover piece of Firestone QuickSeam

FormFlash or Firestone QuickSeam SA Flashing (the latter is preferred: better physical properties and more economical).

• Cuts and punctures in the EPDM geomembrane should be repaired with cured EPDM geomembrane. Round all edges

of the cut so that it cannot propagate underneath the target piece. If this has been done properly, the target EPDM repair

piece can be applied using Firestone QuickSeam Splice Tape and Firestone QuickPrime Plus. A valid alternative is to fully

adhere a piece of QuickSeam SA Flashing using QuickPrime Plus.

• Firestone Lap Sealant is used to seal and mechanically protect the exposed edge of Firestone QuickSeam products.

Lap Sealant is also recommended where edges of QuickSeam FormFlash make a T-crossing with QuickSeam Splice Tape,

QuickSeam Batten Cover or QuickSeam SA Flashing, in order to avoid any risk of possible capillarity.

NOTE: The application of new Firestone QuickSeam products to existing in service EPDM geomembrane requires special

cleaning and priming procedures. Refer to section 4.5.5.

Figure 45: Typical repair of EPDM geomembrane: using QuickSeam SA Flashing

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Figure 46: Typical repair of EPDM geomembrane: using QuickSeam FormFlash

Figure 47: Typical Repair of EPDM geomembrane: using EPDM geomembrane (190 x 150 mm QuickSeam FormFlash patches)

Figure 48: Typical Repair of EPDM geomembrane: using EPDM geomembrane (225 x 225 mm QuickSeam FormFlash patches)

The way of connecting two QuickSeam Splice Tapes in the corners is going to determine the size of the QuickSeam FormFlash

Patch.

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4.5.3. Repair of contaminated EPDM geomembrane

Any Firestone EPDM Geomembrane that has been in contact with hazardous chemical discharges such as fresh bitumen,

petroleum products, greases, oils, animal fats or oil based solvents needs to be inspected for damage.

Remove immediately any excess of the contamination materials and replace the damaged area with a new piece of membrane.

Repairs should be completed as described in Figure 47 and Figure 48.

4.5.4. EPDM field seam repair

As soon as any non-conformity is identified during installation or inspection, mark the damaged area with a white crayon for

use on rubber.

• Punctual defaults or damages on field seams (e.g. wrinkles) in a field splice must be cut out and repaired with

a covering piece of uncured EPDM (QuickSeam FormFlash). Provide a patch that extends a minimum of 75 mm beyond

the perimeter of the damaged area. Wrinkles in a field splice must be cut out using scissors, laying them flat on the

geomembrane, before applying the patch. Clean the area around the damage and adhere the QuickSeam FormFlash with

QuickPrime Plus. Use small silicone rubber roller to roll the edges flat (see Figure 46) and seal with Lap Sealant.

• Non-punctual non-conformities on seams (QuickSeam Splice Tape is not showing, QuickSeam Splice Tape is

showing more than 25 mm, possible water entry points) can be repaired using QuickSeam SA Flashing or QuickSeam Batten

Cover set in QuickPrime Plus.

NOTE: The application of new QuickSeam products to existing in service EPDM geomembrane requires special cleaning

procedures. Refer to section 4.5.5.

Figure 49: Typical seam repair cross section

Figure 50: Typical joint details for non-punctual damages in a splice

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4.5.5. Cleaning of in service EPDM geomembrane

When repairing a Firestone EPDM Geomembrane that has been in service for some time, it is necessary to prepare the surface

to be spliced thoroughly prior to starting the splicing operation.

This is a performance specification. It is required that the EPDM geomembrane be dark gray in color without streaks before

proceeding with any bonding or splicing activity. The cleaned area must be larger than the repair area.

• Cleaning may be achieved by one of the following methods:

- Brush wash by hand with a solution of mild dish soap and water and a stiff bristle brush. Rinse the receiving surface with water until clean. Take care not to flood the receiving surface.

- Use a power water washer and a wet vacuum. Take care not to flood the receiving surface.

• Allow the receiving surface to dry thoroughly. If necessary, dry the washed surface with clean towel or rags. Make sure that

no moisture can be trapped.

• It is also acceptable to sweep the EPDM geomembrane with a broom in the repair area and apply Firestone Membrane

Pre-Wash using a garden sprayer at the rate of 7 to 12 m²/l (300 to 500 sqft/gallon) - contact the Firestone Technical

Department for exact procedure. After the Pre-Wash has dried for approximately ten minutes, use a power water washer

providing 15 l (4 gallon) per minute at 20 MPa (3000 PSI) to remove the Pre-Wash and any accumulated dirt and debris. A

40° fan spray nozzle for pressure washer is suggested.

• Wash the existing EPDM geomembrane twice with Firestone Clear Splice Wash and clean, white, cotton rags, allowing the

surface moisture to evaporate and dry between washing. Change cleaning rags often.

NOTE: After cleaning the in service EPDM geomembrane, proceed with the application of the new

Firestone EPDM Geomembrane, QuickSeam FormFlash, Lap Sealant and QuickSeam Splice Tape in accordance with current

Firestone application specifications.

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