Bare Geomembrane Specifications

This is a sample specification for a leak location survey for a bare geomembrane with a conductive material under the geomembrane. It is applicable for qualifying primary or secondary geomembranes. This section should be used as a guide, and not used verbatim. Please review the text carefully and make changes appropriate for each application. This specification is not applicable for testing the primary geomembrane of a double geomembrane liner with only geonet between the geomembranes. It may not be applicable for other configurations. This specification may be used as a part of other specifications for more complex lining systems. Leak Location Services, Inc. ([email protected]) (210) 408-1241 will review your particular application and recommend any changes to the specifications if needed. SECTION 02777 GEOMEMBRANE LEAK LOCATION SURVEY OF BARE GEOMEMBRANE PART 1 – GENERAL 1.1 SECTION INCLUDES A. Requirements for performance of a geomembrane leak location survey using the water puddle electrical method for post-geomembrane installation performance for a bare geomembrane underlain by an electrically conducting material. B. Requirement to perform a geomembrane leak location survey before subsequent materials are placed on the geomembrane. C. The optimum performance of a water puddle geomembrane leak location survey requires an electrically conductive media below the geomembrane. In arid locations it may be necessary to wet the geomembrane prior to the leak location survey to sufficiently wet the subgrade under the leaks. 1.2 RELATED SECTIONS A. Section ______ – Geomembrane B. Section ______ – 1.3 REFERENCES A. ASTM D6747 – Standard Guide for Selection of Techniques for Electrical Detection of Potential Leak Paths in Geomembranes B. ASTM D7002 – Standard Practice for Leak Location on Exposed Geomembranes Using the Water Puddle System 1.4 SUBMITTALS Leak Location Contractor shall submit a Leak Location Survey Work Plan to Engineer for approval prior to commencement of the leak location survey. The Leak Location Survey Work Plan shall include: 1. Qualifications of Leak Location Contractor to include the number of years Leak Location Contractor has performed the survey method; 2. Resumes of on-site supervisors; 3. Description of the survey method, and procedures; 4. Required site preparations; 5. Estimated duration of survey; 6. Quality control and field calibration procedures; 7. A list of projects demonstrating the qualifications and experience where Leak Location Contractor and leak location supervisor have met the requirements of paragraph 2.1 of this specification. 8. Sample of a final report (per ASTM D7002) provided by Leak Location Contractor following the completion of the survey. 1.5 CONSTRUCTION QUALITY ASSURANCE A. The leak location survey shall be observed by CQA Consultant. B. Contractor shall be aware of the leak detection activities outlined herein and shall account for these activities in the construction schedule. PART 2 – PRODUCTS 2.1 LEAK LOCATION CONTRACTOR AND SUPERVISOR QUALIFICATIONS Leak Location Contractor shall have qualifications and experience in conducting the survey method including having tested a minimum of 15,000,000 square feet of geomembrane liner within the previous three years. In addition, the leak location surveys must be supervised by a professional or technician with a minimum of three years and 1,000,000 square feet of testing experience using the leak location survey method. The leak location supervisor must be on site full-time during the performance of the leak location survey. A qualified Leak Location Contractor is Leak Location Services, Inc. tel. (210) 408-1241. PART 3 – EXECUTION 3.1 INFORMATION REQUIRED CQA Consultant firm shall provide Leak Location Contractor with drawings showing: 1. All layers constituting the lining system. 2. Details of all geomembrane penetrations. 3. Peripheral details, including welds to adjacent lining systems 4. Structures and obstructions above the geomembrane. 5. Electrical equipment above the primary geomembrane. 3.2 SITE PREPARATION A. Leak Location Contractor will identify actions required by Contractor to prepare the site for the leak location survey. B. Contractor shall ensure that the materials below the geomembrane contain sufficient moisture to conduct a leak location survey. Typically, a moisture content of more than two percent by weight is sufficient to conduct the survey. If the geomembrane is installed on a desiccated (dusty) subgrade, or on a geotextile, it will be necessary to spray the geomembrane with water prior to the leak location survey to allow time for the subgrade at the leaks to be wetted. 3.3 EXECUTION A. Leak Location Contractor shall inspect the site prior to commencing the survey to ensure all site preparations are completed and the site conditions are appropriate for conducting the leak location survey. B. Any discrepancy in the required site preparations described in the Leak Location Survey Work Plan or site conditions shall be reported to Contractor for corrective or appropriate action. C. It is recognized that the leak location survey cannot be conducted in areas that are immediately adjacent to the edges of a single geomembrane or immediately adjacent to electrical conducting paths through or around the geomembrane such as earth ramps, metal pipes, battens, or concrete structures. D. Conduct a leak location survey on the bare geomembrane using the procedures described in the latest version of ASTM Standard D7002. E. Leak Location Contractor shall inform the CQA Consultant and mark the locations of all identified or indicated leaks with flags, spray paint, or written coordinates. 3.4 REPORTING Provide a written report within 14 calendar days of completion of the leak location survey field work as described in ASTM D7002. END OF SECTION