Geosynthetics 2015

February 15-18, Portland, Oregon

Covering Your Assets—Construction Quality Assurance Glen W. Toepfer, CQA Solutions, Ltd., USA, gwtoepfer@cqasolutions.co Shabbir Pittalwala, Arizona Public Services, Shabbir.Pittalwala@aps.com ABSTRACT Containment projects are important corporate assets that ensure the company’s ability to generate cash flow. As such, asset procurement and management are vital to ensuring and improving the asset’s Return-on- Investment (ROI). Solid Construction Quality Assurance (CQA) is an important insurance policy that ensures an improved ROI and maintains the ability to use the asset for the future benefit of the organization. Insurance investments are based on a Risk vs. Reward formula. Because geomembrane is the main containment layer, this paper will focus on evaluating the Risk vs. Reward of a typical geomembrane installation. We will review a typical geosynthetics installation process, expose common risks associated with each stage and identify the role of CQA within each stage. The reader will then be provided an evaluation tool that can be completed for a project specific risk assessment that will allow you to maximize your ROI with a customized CQA plan. 1. INTRODUCTION 1.1 Containment Facilities are an Asset According to Investopedia an asset is defined as “A resource with economic value that a corporation owns or controls with the expectation that it will provide future benefit.” The purpose being: “ Assets are bought to increase the value of a firm or benefit the firm's operations, something that can generate cash flow.” Containment installations are assets. They provide economic value and future benefits. They are a part of the process that enables companies to generate cash flow. Like all assets, ROI is very important to the company’s profitability. As such, making smart investment decisions that ensure future benefits are critical. Waste containment assets can directly increase a corporation’s profitability by generating revenue, expanding plant capacity, improving efficiency, or even just the ability to extend the life of the business. However containment assets can also have a negative impact on a corporation through operational delays and/or shut downs, environmental contamination, negative publicity and even lives lost. 2. CONSTRUCTION QUALITY ASSURANCE (CQA) 2.1 CQA Defined As the owner of a valuable asset, one of the first things you want to do is protect its value and protect it from damage. If the asset is a car or a house, you buy an adequate amount of insurance. During a construction project, CQA is your insurance. The following is the industry’s standard definition of CQA taken from the Geosynthetic Institute’s (GSI) website: “Construction Quality Assurance (CQA): A planned system of activities that provides the owner and permitting agency assurance that the facility was constructed as specified in the design. Construction quality assurance includes inspectors, verifications, audits, and evaluations of materials and workmanship necessary to determine and document the quality of the constructed facility. Construction quality assurance (CQA) refers to measures taken by the CQA organization to assess if the installer or contractor is in compliance with the plans and specifications for the project.” While the Resource Conservation and Recovery Act of 1976 (RCRA) brought about the requirement for CQA in the waste containment industry, other markets such as shale gas and mining are relatively new and emerging markets. Regardless of the sector, the role of CQA remains the same: ensure that the containment unit is built to maximize the client’s ROI. In summary, the role of CQA is to assure the construction is being performed in accordance with the design specifications and plans. This execution should provide you with the maximum ROI through out the life of the containment cell.

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2.2 The Importance of CQA Numerous studies show that the integrity of a liner system is increased with the presence of a competent CQA team. For instance in a 2005 study on exposed geomembranes, an average geomembrane leakage rate of 9.0 leaks/acre was observed in 14 projects constructed without CQA, while the average dropped significantly to an average of 1.6 leaks/acre (4047m

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where CQA was performed in a sample of 43 projects. (Forget, et al., 2005). In her 2012 paper, How Much Does my Landfill Leak, Abigail Beck summed up the value of CQA effort with two statements. “Average hole size and frequency contributing to

leakage depends heavily on the skill of the liner installer and the skill of the CQA agency” and “This concept can be expanded to an improvement in construction quality with rigorous CQA as opposed to poor or inattentive CQA.” (Beck, 2012). The consistent message from these resources and other industry professionals are that competent CQA can be very effective at reducing holes remaining in a liner system after completion of the installation. This message should be broadened to state that competent CQA can reduce the risk of other failures as well, some of which can be catastrophic. 2.3 Choosing Your Coverage CQA Services, like many insurance policies, are often thought of as a “necessary evil” until they are needed. Having the right insurance for the right moment is priceless. So the question always becomes: what insurance should I purchase and how much should I spend? Like insurance policies, the choices on what CQA coverage you need on a project can be confusing. You have to weigh the risks associated with installation activity in order to evaluate the coverage you feel comfortable with in order to maximize your specific project needs. Every owner, every project, every installer, and every CQA firm are different in their approach to managing their geosynthetic assets. In order to perform an accurate evaluation, we need to look at the typical process of a geosynthetics installation and the role of CQA during each process. If we then factor in the potential for short term and long term damages that may occur during each of these processes, we can assign a relative risk level to each item that can be tailored to any specific project. Because of project variance, we can only assign relative risk and not actual cost. For the purposes of this paper, it will be assumed that the design has taken into consideration proper materials for the specified application, and that a competent installation firm has also been selected to perform the construction. Using subpar materials or installation teams will add a significant chance for both short-term and long-term problems, as well as result in an increase in CQA cost. 2.3.1 Experience, Education and Expectations As the owner, your expectations for quality should remain firm and unyielding. CQA technicians are the eyes and ears of the site owner working to ensure that projects are meeting and/or exceeding expectations. One of the biggest challenges in the industry is comparing apples to apples as far as experience goes. All technicians are not equal and years of experience often does not indicate true field success. Twenty-five years of industry experience has shown that a good 2-year technician can out perform a mediocre 18-year veteran on many occasions. At the same time there is no substitute for true field experience and the knowledge that comes from it. So how do site owner hire the right team? To date there is no testing and/or certification process that accurately quantifies the field capabilities of CQA Technicians. Each site owner needs to have an evaluation process that measures the experience level of his or her technicians and how that experience level translate into the actual field CQA performance. Evaluation processes can include items such as: site owner testing for knowledge and correct field processes, years of experience, project background, interviews, references and completed training programs. Training programs can be internal training and field mentoring processes provided by the CQA Firm, external training classes or programs such as the Geosynthetic Certification Institute’s Inspector Certification Program (GCI-ICP) established through the Geosynthetic Institute (GSI). While this might appear to be a rather vigorous approach, the reality is that these technicians often determine the fate of your multimillion-dollar projects.

3. RISK ASSESSMENT 3.1 Purpose Although CQA is often thought of as strictly field inspection and documentation services, the scope of service first involves significant upfront management, coordination, and review services. With the onset of construction, the field services and daily management provide the bulk of the CQA service, which is typically wrapped up when the certification report is not only completed, but also approved by the governing regulatory agency.

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There are plenty of CQA steps in between, which can be broken down into relatively specific tasks based on pre-installation, installation, and post-installation activities discussed below. The Risk Assessment tool in Table 1 allows us to assign the risk levels for each of the following tasks. The risk assessment evaluates the risk in 5 separate categories then sums up the total risk value for each area allowing you to customize your CQA plan based on the areas of greatest vulnerability. The risk assessment is best completed and evaluated before finalizing the project plans and specifications when possible. This allows the site owner and project engineer to firmly establish proper protocols before completion of the bid package, thus assuring the asset protection plan and mindset will be carried through the entire project, ensuring quality every step of the way.

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Table 1. Risk Assessment Tool

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3.2 Geosynthetics Installation and CQA Tasks Below are some of the common tasks relating to a geomembrane installation using the more common thermal and extrusion welding techniques. In order to effectively evaluate the risk vs. reward, we must look at other construction activities that have a direct impact on the integrity of the geomembrane and where CQA is typically performed. This paper will evaluate the standard components of each task listed and discuss the possible risk/failure opportunities associated with the task. 3.2.1 Pre-Installation The CQA process starts with familiarization and review of the project design plans and specifications. Proposed the CQA firm reviews material submittals and third-party conformance testing of the materials is planned, implemented, and results are reviewed. Right away, the CQA firm must have a sampling strategy for which they are comfortable, and each comes with it’s own set of risks. The choice of whether to follow the industry norm and have third party plant sampling performed, or performs field conformance sampling.

3.2.1.1 Plant Conformance Sampling In plant sampling is typically contracted out to another third party with a presence in or near the manufacturing facility, rather than pay to send one of his or her own personnel to the manufacturing facility. One of the biggest advantages of in-plant conformance sampling is that the material is sampled prior to shipment; so failed material does not leave the plant.

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3.2.1.2 Field Conformance Sampling Personnel from the CQA firm usually perform field conformance sampling once the material arrives on site. One of the big advantages of field conformance sampling is that the CQA firm can actually pick rolls to be sampled based on what they are visually observing on the outer wraps of the material. The drawbacks are a delay in obtaining results, as well as having material shipped that may not pass testing. 3.2.2 Material Inventory, Inspection, Segregation Upon arrival, the materials will be inventoried by the CQA firm, and inspected for proper storage and damage. Damaged, unidentifiable, or wrong materials, or those failing to meet specifications will be marked and set aside. Inventory control is essential for all products in assuring they are used in accordance with the design. 3.2.3 Subgrade Acceptance Regardless of the material and/or layer being placed, subgrade acceptance is critical to the long-term functioning of the system. Subgrade serves as the foundation for the liner system and therefore must meet the intent of the design for the geosynthetics to properly function without incurring unnecessary damage. CQA personnel must inspect the subgrade to assure it conforms to the design plans and specifications. 3.3 Installation 3.3.1 Geomembrane Deployment

CQA personnel must first make sure that the proper material is being deployed. Because many materials look similar once they are deployed, the best time to catch an error is before or during the deployment. During and immediately after a panel is deployed, the entire panel must be walked to assure inspect for material blemishes, irregularities, or anything else that would warrant removal of all or a portion of the panel, such as excess damages. CQA personnel also need to make sure the material is deployed to the limits, and deployment follows the design (overlap shingling, anchor trench configurations, etc.) and should keep an eye on material waste. 3.3.2 Trial Seams Trial seams are a vital step in assuring the operator/machine combination can successfully perform the required welding under the current conditions. CQA personnel should be making sure the trial seams are being prepared physically in accordance with the specifications as well as at the frequency required by specifications. Test coupons being cut from the trial seam must be spaced out in accordance with the specifications as well as cut to the proper dimensions. Likewise, the coupons must be tested in accordance with the specifications, both in terms of testing speed, and testing conditions (temperature, humidity, etc.). Lastly, the CQA technician needs to make sure the values and peel separation meet the specifications, and that any failures are reworked and retested in accordance with the specifications. 3.3.3 Fusion Seaming CQA personnel need to make sure that all seaming is being performed in accordance with the specifications—this includes the overlap, trimming, cleaning of seams, sheet and ambient temperatures, and in some instances apparatus temperatures. Often overlooked are the Manufacturer’s power supply requirements, which dictate the electrical output required, extension cord length and gauge limits, etc. 3.3.4 Extrusion Seaming/Repairs Due to the knowledge that extrusion seaming is an inferior weld when compared to fusion seams, many specifications have initiated the concept of minimizing extrusion weld seams and repairs (example: if a repair will exceed 10’ (3.048 m) in any dimension, a fusion repair will be used to fix the damage). That being said, extrusion welding is a critical component of any geomembrane system (where materials are compatible with extrusion welding). CQA personnel need to make sure all damages are located, proper repairs for the damage type are being performed, proper preparation of the damage is being performed prior to the repair (i.e. circle cuts, rounding cut corners, etc.), and proper repair materials and procedures are being used in accordance with the specifications. CQA personnel also need to make sure all damages have been properly repaired. Like fusion seaming, the manufacturer’s power supply requirements should be followed to have consistent weld quality throughout the project.

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3.3.5 Non-Destructive Seam Testing Regardless of the method of non-destructive seam testing, CQA personnel need to make sure every inch of every seam is accounted for in testing as well as assuring the testing equipment both meets the specifications and is functioning properly. Proper pressures, as well as, dwell times need to be observed. Clear communication needs to occur when there are failures, to make sure the failures are properly repaired and retested. 3.3.6 Destructive Seam Sampling Destructive seam sampling can be broken up into three main components: location selection, field-testing, and laboratory sampling.

3.3.6.1 Location Location of samples needs to be in accordance with specifications and there is a balance that needs to be worked out between cutting additional holes in the liner in critical areas verse taking too many samples that are not representative of the actual installation. Each project is different, and therefore each may have different sampling criteria. However, technicians and project managers alike need to be aware of the 500 foot (152.4 m) spacing trap, where samples are strictly marked on a set lineal foot distance instead of taking into account both questionable areas and reducing holes in critical areas when possible.

3.3.6.2 Field Testing Once destruct locations are selected, field-testing of the samples should be performed. Sometimes, field-testing is a mandate in the specifications; other times, it is dependant solely on the installer. Likewise, the number of coupons tested will vary from site to site and crew to crew. CQA monitoring of the field-testing is always recommended, regardless of if it is in the specifications or not. Consider it sort of a double jeopardy in that you have two pieces of verification for that particular sample instead of one—so in theory you should be more likely to catch something. Likewise, a lot of time and money can be saved if field failures are reported rather than shipped to a laboratory, which adds both time and money.

3.3.6.3 Laboratory Testing The third component to be considered is laboratory testing. Timely results are critical for both the installer and the overall quality of the project—the sooner a failure or trend can be identified, the sooner it can be resolved. One way of expediting the turn-around, as well as providing feedback a laboratory cannot always give you is third party testing of destructs on-site. However, this requires competent people familiar with the materials, welding procedures, and testing methods available to perform the testing. 3.3.7 Bare Geomembrane Geoelectrical Testing Given the availability of various geomembrane sheets with conductive composition and designs that allow for continuity testing, bare geomembrane testing can find pinhole sized flaws that are easily missed by even the most diligent CQA personnel. For this testing to be effective, CQA personnel must be diligent in not only assuring 100% coverage of the panels, but also monitor things such as the wand remaining in contact with the material as the operator pushes it over wrinkles, repairs, and seams, and that the area is free of water (when a spark test used) and dirt/dust that can negate the effort all together. 3.3.8 Final Walk-Through A final walk-through between QA and QC (these parties at a minimum) should be performed prior to releasing any panels to be covered by another material. This walk allows involved parties a final chance to again inspect 100% of the geomembrane for continuity and testing, as well as any damages that may have occurred after the installation progression was completed in the area. It is also a good idea to make sure any as-built surveys have been performed before releasing the area (ideally they are performed prior to the bare geomembrane testing). 3.3.9 Subsequent Material Placement Whatever the material that is placed on top of the geomembrane, CQA needs to maintain the inspection level of effort comparable to geomembrane CQA. This does not mean as many inspectors may be needed, but it means that there should be eyes on any processes occurring on top of the geomembrane, which could cause damage. Damage happens during these

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subsequent installations, whether the material is a geosynthetic, or a soil or aggregate, and once the damage is covered, it may not be found again for a long time. 3.3.10 Dipole Geoelectric Surveys One way of finding damage that has occurred during subsequent material placement over a geomembrane is using the electrical leak detection survey. Specific criteria are required for the survey to function properly (such as intimate contact of the geomembrane with the conductive surface meaning voids caused by wrinkles may be problematic), so it is imperative that CQA not only observe the installation of these materials, but also make sure the installation is performed from beginning to end with the leak integrity survey in mind. Likewise, there needs to be a way of verifying that 100% of the area has been covered. 3.3.11 Daily Project Management Throughout the course of the project, it is imperative that data review be performed on a timely basis. It never hurts to have more than one set of eyes review any particular data set. Project management also consists of trouble-shooting when problems arise, responding to regulatory and owner questions, and keeping a day-to-day pulse on the project. 3.4 Post-Installation 3.4.1 The Certification Report The certification report is the one deliverable that is tangible. It is a tangible record that should show everything was constructed to the intent of the approved design. It is tangible in that it gives the regulatory agency something to review in order to approve the project construction. It is tangible in that it gives an owner something to place a cost on. It is also tangible in that, once approved by the regulatory agency, it signals the end of the construction phase and the beginning of the long-awaited usage phase. 3.5 Analysis When evaluating the risk analysis, it is important to understand the difference in impacts between the columns. A construction delay can have significant consequences in terms of not only obtaining timely certification, but also in terms of facility operations that ultimately effect revenue streaming; similarly, the certification delays can the same effect. However, when comparing either of the two aforementioned items with post operational delays, the cost of such delays usually increases; likewise, an environmental impact may be a long-term consideration but the cost will be significantly more to address and such events can trigger a public perception that can be a huge obstacle to overcome. Therefore, depending on the specific company and their goals, as well as market sector, it may be advisable to weight some of the categories. Each company, each industry, and each project will have their own unique set of goals, which may lend to individual tweaking of the risk assessment to suit their fundamental needs as well as tolerance to risk. However, the bottom line to keep in mind is the cost of system failure.

4. THE PRICE OF FAILURE While every project varies, the reality is that cost of failures will always impact your operations and your bottom line. In looking at the tangible cost of failures, the 2005 White Paper titled Geosynthetics Risk Management and Loss Control Program (Peggs and Peggs, 2005) shows the cost to repair failures ranged from 30 times the cost of prevention up to a staggering 2300 times the cost of prevention. It is hard to even fathom that $10,000 of prevention could have saved $23,000,000 in repairs. While some damages may fall under the installation or manufacturers warranties, most damages will not—in the case of those in the aforementioned White Paper, none of the repair costs were covered by insurance. 4.1.1 Warranties Certain damages recognized shortly after completion of the installation may fall under the installation warranty, which is typically good for a period of a year after completion, although parties in certain cases may modify it. Other specific damages may be found and fall under the manufacturers warranty, which is typically good for a period of 5 years. As anyone who has ever dealt with a warranty is aware, they need to be read carefully and understood. For instance, while the installer will cover the cost of performing a repair under the installation warranty, they will not be the ones bearing the cost of preparing area to allow the repair to be performed. This means the owner is going to bear the cost of removing any solid or

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liquid that is in the way of getting the repair done and potentially any cost associated with the environmental impact of the failure. The bottom line is even if the failure is covered by insurance and a warranty the failure will cost you. 4.1.2 The Cost to Owner for a Single Warranty Repair As an example, at the Palo Verde Nuclear Generation Station facility, evaporation pond 2A (117 acre footprint or.4735km

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full capacity would need to remove 780 million gallons of water and sludge just to make one repair—a process that would take 120 days. Not only is the direct cost of dewatering the pond potentially bore solely by the owner, the cost of impacting operations such as lost plant efficiency, lost storage capacity, and lost ability to generate revenue may be as well. In addition, on any facility, there will be time to not only find the leak, but also get it properly repaired, and the facility put back into service. This can be greatly compounded if there are multiple leaks in multiple locations. In the Palo Verde example, the dewatering process for a pond this size would cost approximately 4 % of the total construction cost for the pond. 4.1.3 Case Study Summation

Table 2 was obtained from the Geosynthetics Risk Management and Loss Control Program White Paper and serves as an example of the need to weigh current costs versus long-term costs and ultimately the cost of failures.

Table 2. Cost of Failure vs. Cost of Prevention

Cause of Failure Cost of Failure

Cost of Prevention

Prevention vs. Repair Cost Multiplier

Improper Design > $600,000 $20,000 30

Poor Installation and No CQA

$1,300,000 $15,000 87

Poor Design and Installation and No CQA

$21,000,000 $40,000 525

Material Selection $23,000,000 $10,000 2300

As you can see from the table, there are considerable long-term costs associated with failures, whether they are caused by improper design, improper or incorrect use of materials, poor installation, and lack of or poor CQA efforts. 5. CONCLUSION

CQA personnel are ultimately the eyes and ears of the owner and must have a constant hand on the pulse of the project—as such, they can provide significant ROI over the lifetime of the project. There are tools available to assist CQA personnel in accomplishing their role effectively, and when these tools are effectively used, studies have shown a significant reduction in the amount of damages occurring and/or remaining after construction is complete. Each owner needs to evaluate their particular site, and make quality decisions based on their expected ROI. In order to make the most educated decision, the owner must incorporate corporate goals and evaluate the immediate, short-term, and long-term risks associated with each stage of geosynthetics installation and weigh those costs against the cost of quality CQA efforts that can mitigate those risks. By being pro-active, the owner, installer, and CQA firm will be able to work together and achieve a successful project while maximizing investment ROI. REFERENCES Beck, A. (2012). How much does my landfill liner leak, WasteAdvantage Magazine, December Issue. Forget, B., Rollin, A.L., Jacquelin, T. (2005). Lessons learned from 10 years of leak detection surveys on geomembranes, In

Proceedings of Sardinia ’05: The Tenth International Waste Management and Landfilling Symposium, October 3-7, Cagliari, Italy, Environmental Sanitary Engineering Centre, University of Cagliari, Italy.

Geosynthetic Institute (n.d.). Introduction to geosynthetic certification institute-inspectors certification program, GSI. Retrieved April 4, 2014, from http://www.geosynthetic-institute.org/icpintro.htm.

Peggs, I. and Peggs, E. (2005). Geosynthetics risk management and loss control program, White Paper.

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