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5 Role of Third-Party Oversight and Certified Verification Agents Third-party review of design and construction of infrastructure has a long history. This chapter provides the historical context for infrastructure review, then progressively narrows the scope to practices for land-based energy facilities, offshore oil and gas facilities in the United States, offshore wind energy facilities, and finally to the role of a certified verification agent (CVA) for offshore wind energy facilities. BACKGROUND Nearly all incorporated cities and communities along with many states and counties have adopted building codes for facilities and high-consequence public infrastructure, and they have ordinances requiring compliance of design with the applicable building code and construction in accordance with the design. One of the two model building codes, as modified for unique local conditions, is usually adopted. A permit process and building inspections are coupled with the building code. Most jurisdictions issue building permits after review of plans by officials within the jurisdiction; the buildings are subject to inspection during construction. Other types of infrastructure have third-party review or authorization processes as well. Examples of well-known processes are those developed and implemented by the Federal Aviation Administration for aircraft and those administered by the Nuclear Regulatory Commission for nuclear power plants. The offshore oil and gas industry operates with a two-tier oversight process under the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE). For facilities of lower complexity and generally lower potential consequences due to an incident, structural plans must be 96

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Role of Third-Party Oversight and Certified Verification Agents 97 stamped by a registered professional engineer, and BOEMRE staff check submittals against regulatory requirements. For facilities of greater struc- tural complexity, the CVA program has been developed, and compliance with it is required. Well over 200 years ago, the shipping industry began an oversight process driven by insurance brokers. A number of third-party companies that became known as classification societies developed guidelines cov- ering design conditions, inspection scopes, and provisions for periodic inspection of vessels, which provided the insurance brokers a baseline reliability reference. A classification society is a nongovernmental organization or private company that develops technical rules and requirements for the design and construction of ships and other marine structures (referred to as class rules) and then ensures compliance with the rules through surveys con- ducted during construction and throughout the life of the vessel. Classi- fication is generally required by flag states as well as underwriters, and most oceangoing cargo ships are maintained in class. The European practices and regulations for wind energy turbines were presented in Chapter 3. Primary oversight or review is embedded in the type certification and project certification protocols. Additional oversight may be requested by insurance or project financing entities; however, practices are not uniform. OFFSHORE OIL AND GAS: HISTORY OF USE OF CVAs 1977 National Research Council Study In the 1970s, oil exploration and production offshore the United States were increasing rapidly in scope and complexity. The number of wells, the number of facilities, and production volumes grew, and exploration and production extended into deeper and deeper waters. While the greatest focus was in the Gulf of Mexico, activity was under way offshore Alaska and California. Exploration was active as well off the northeast coast. In 1977, the U.S. Geological Survey (USGS), which at the time handled the responsibilities handled today by BOEMRE, requested the National Research Council (NRC) to undertake a study to determine whether inde- pendent third-party review of offshore structures would be of benefit to

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98 Structural Integrity of Offshore Wind Turbines the federal government. At the time, the federal regulations embodied within Outer Continental Shelf (OCS) Order 8, the forerunner of Title 30, Part 250, of the Code of Federal Regulations (CFR), required the struc- tural design of an offshore facility to be stamped by a registered profes- sional engineer. The NRC study (Marine Board 1977; Gerwick 1977) determined that a third-party review would be of value and recommended that a process be developed and implemented by USGS. Subsequently, USGS developed and implemented a process, known as the CVA program, that is still part of the facility oil and gas permitting and approval process overseen by BOEMRE. The charge to the NRC panel covered fixed offshore platforms. Today, the oil and gas CVA program covers not only fixed offshore platforms but also permanent floating facilities and deepwater production riser systems. One of the first topics addressed by the panel was the implications of terminology. “Certification” by a “certified verification agent” had a num- ber of perceived definitions, and specific programs were associated with the term “platform certification” in some European regulatory regimes. There was concern that certification might imply that the structure was certified to withstand all environmental and man-made impacts upon the structure. However, it is not possible to certify uncondition- ally that the platform will at all times be safe for operating personnel, or with- stand the effects of all storms and seismic conditions, collisions or accidents or that the environment will not be endangered. Nevertheless, a procedure is required, whatever its designation, to assure the public, the Congress, the USGS and the owner/operator of the platform that the environmental and operating factors have been given consideration in the platform design, construction and installation. This procedure should also indicate that appropriate reviews and inspections have been conducted to doc- ument that the design, building, and installation of a platform are in confor- mance with the applicable performance criteria, specifications, etc. This procedure has been identified as “verification.” (Marine Board 1977, 8) The study recommended that USGS, in addition to instituting a verifica- tion program, increase staff capability for assessing agent competence and approving facility permits. The scope of a verification program was outlined. Three distinct areas— design, fabrication, and installation—were described and recommended

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Role of Third-Party Oversight and Certified Verification Agents 99 for oversight. Because of the differing skills required in these areas, the rec- ommendation provided that verification in each area could be performed by independent organizations. The recommended process was outlined as follows: 1. The operator submits a plan for third-party verification of the structure to USGS. 2. USGS checks the plan, either in-house or by using a contractor. 3. USGS approves the plan if it is adequate (an appeal procedure is avail- able in case approval is denied). 4. The plan is implemented by the third-party engineering and inspection representatives (CVAs) indicated in the plan. 5. USGS monitors implementation of the plan for compliance. 6. USGS institutes a failure reporting and analysis system. 7. An independent government board conducts or reviews investigations of major accidents (this recommendation was never implemented as envisioned). The verification plan submitted by the operator should set forth the following: • Environmental criteria to be used; • Design criteria and procedures to be used; • Fabrication procedures to be used; • Installation procedures to be used; • Operating procedures to be used, including postinstallation inspec- tion and maintenance procedures; • Techniques and procedures to be used in verification (tests, inspec- tion procedures, etc.); and • A list of the independent third-party verification agents proposed to be employed. During the design phase, 30 CFR 250 specifies standards with which the facility must comply. These standards, for offshore U.S. waters, are the American Petroleum Institute (API) Series 2 standards, such as API RP 2A-WSD, 21st edition, for fixed offshore platforms and API RP 2T for tension leg platforms. They are U.S. national standards carrying the American National Standards Institute designation and comply with the

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100 Structural Integrity of Offshore Wind Turbines institute’s requirements of open development procedures, including public participation in the development, review, and approval stages. All comments to proposed standards must be addressed and resolution of comments documented. While the standards are shepherded by an indus- try organization, they are delivered as U.S. national standards. Early Years of the CVA Program In the early 1980s the Minerals Management Service (MMS) maintained a list of preapproved CVAs. An organization could petition MMS to approve it as a CVA for design, fabrication, or installation on the basis of the organization’s capabilities. Approval was granted for a period of 3 years. An operator could choose from the list of preapproved CVAs or propose another organization for approval to function as a CVA on a given project. After several years, MMS discontinued the practice of preapprov- ing CVAs because of difficulties in maintaining the list and the relatively few facilities requiring use of a CVA. Only a small subset of the approved CVAs were actually selected and used. Initial CFR and Notices to Lessees USGS implemented a CVA program through provisions in OCS Order 8 (later incorporated into 30 CFR 250 Subpart I) and various notices to lessees. The program initially covered structural aspects of fixed platforms and has been expanded to cover structural and station-keeping aspects of permanent floating production facilities and production risers for the float- ing facilities. The drilling and process systems of the offshore facilities have not been covered under the CVA program. The CVA program can be summarized as follows: 1. Design, fabrication, and installation have been designated as distinct phases of a project, and each phase must be verified. 2. A single CVA can be approved for all three phases, or individual CVAs can be approved for each of the three phases. 3. Initially, individuals or companies could petition USGS to be approved as a CVA for a given phase or for multiple phases on the basis of com- petency. On acceptance by USGS, approval was granted for 3 years. USGS maintained the list of preapproved CVAs by phase.

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Role of Third-Party Oversight and Certified Verification Agents 101 4. Alternatively, an owner could nominate a CVA for a phase of a project if the proposed CVA was not already on the approved list. USGS reviewed the credentials of the nominee in the same manner as those of a CVA requesting preapproval. If the nominee was deemed quali- fied, approval as the CVA was granted for the requested project, and the nominee was added to the preapproved list. 5. The approved CVA reviewed the appropriate documentation or field activities and submitted interim reports as outlined in the CVA pro- posed scope of work as well as a final report to USGS. 6. USGS maintained responsibility for assessing the qualifications of a CVA, approving a CVA for a given project, and reviewing both the facility owner’s documentation and the CVA reports. It made the final determination as to the acceptability of the proposed facility. The NRC study recommended that all future facilities be included within the CVA program. When it was implemented, however, the pro- gram excluded routine facilities from the CVA scope and included only • Platforms with natural periods greater than 3 seconds, • Platforms installed in water depths exceeding 400 ft, • Platforms installed in areas of unstable bottom conditions, • Platforms having configurations and designs that have not previously been used or proven for use in the area, and • Platforms installed in seismically active areas. The first platforms to undergo the full CVA program addressing design, fabrication, and installation were installed off the coast of Cal- ifornia in 1981, a seismically active area. In developing the details of the CVA program within USGS, the Shell Cognac platform, installed in 1978, was used as a test case to help develop the CVA protocols and procedures. After implementation of the program, floating facilities were consid- ered for U.S. offshore waters, and a new item was added to the list of those required to use a CVA: all new floating platforms. The CVA program could be viewed as a supplement to the government staff’s ability to review platform installation permits, witness on-site fab- rication and installation, and verify compliance with design requirements and fabrication specifications.

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102 Structural Integrity of Offshore Wind Turbines The CVA program remains essentially the same as when it was con- ceived and implemented in the late 1970s. BOEMRE no longer maintains a preapproved list of CVA organizations, and an owner nominates CVAs for each project. Through 2009, 103 fixed platforms and 41 floating facil- ities have come under the CVA program.1 Details of the CVA program, including general requirements for plat- forms and details of the Platform Approval Program and the Platform Ver- ification Program, can be found in Sections 250.900 through 250.918 of 30 CFR 250 Subpart I.2 CURRENT BOEMRE REGULATORY PROPOSALS FOR OFFSHORE WIND TURBINES AND USE OF CVAs The regulations codified at 30 CFR 285, current as of September 30, 2010, contain requirements for CVA responsibility and scope parallel to those for the offshore oil and gas industry, which have been in effect for 30 years and are described in 30 CFR 250 Subpart I. All the attention for CVA activ- ity is focused on the structural and foundation aspects of the facilities. The key difference is the option that the offshore wind facilities have to waive the CVA elements via petition under specific circumstances. The role of the CVA as described in 30 CFR 285 is parallel to the role of the CVA for oil and gas facilities described in 30 CFR 250—to review, assess, and com- ment to BOEMRE.3 Maintaining this advisory role is a critical element of any third-party review process. SCOPE OF REVIEWS While the current oversight model for offshore wind energy facilities is based on the offshore oil and gas program, the scope of the latter may be considered too narrow. The offshore oil and gas industry can be parti- tioned easily into structural, process, and drilling segments. In view of BOEMRE’s expertise and its programs for drilling and process systems, there is a logic to limiting the CVA scope to the structural segment in meeting BOEMRE objectives for offshore oil and gas governance. 1 Presentation by Thomas Laurendine to the committee, 2010. 2 Appendix B of this report contains the text of 30 CFR 250, Sections 916–918. 3 Appendix B of this report contains the text of 30 CFR 285, Sections 705–713.

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Role of Third-Party Oversight and Certified Verification Agents 103 The same division cannot be made as easily for offshore wind energy systems for several reasons: • The blades and nacelle assembly are critical components in maximizing the return to the U.S. government. • A design, manufacturing, or installation flaw in any of the elements of an offshore wind facility will likely affect a significant percentage of a wind farm, not merely the one facility. • The control elements including gearing, software and hardware systems, sensors, and power supply may be critical in the ability of a blade, nacelle, and support system to maintain integrity in severe weather conditions. • The dynamics and relative stiffness of the supporting structural and foundation components, commonly envisaged as a monotower in shal- low water (but which could be a vertical axis system, a floating system, etc.), have an interrelationship with the stiffness and rotation frequency and loads of the blades that must be carefully addressed in the design for long-term performance. Hence, it may be desirable to make the scope of the wind energy CVA program much more comprehensive. Figure 5-1 identifies the key components of a wind energy system. For comparison purposes, Item G, the electric support platform, can be viewed as analogous to an oil and gas platform. Table 5-1 compares the scope that may be necessary to ensure coverage for a wind energy facility with that of an oil and gas facility. Table 5-1 also has a column headed “type certification.” That column represents the elements that would be satisfied under a comprehensive CVA approach. As can be seen, only two elements, those of a design CVA scope, would be covered for a turbine–nacelle–blade–tower assembly that was type-certified to the International Electrotechnical Commission (IEC) process (see Chapter 3). “Type certification” addresses the design of a blade–nacelle–tower subsystem in meeting a set of criteria. Physical proof testing of one man- ufactured blade demonstrates the product’s capacity and performance (strength, deflection, etc.) in terms of the design definition. Type certi- fication does not provide confidence that products as produced meet the design conditions. In other words, the ability to manufacture one device does not ensure that all devices will be manufactured to the same performance characteristics. Type certification is not sufficient in terms

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104 Structural Integrity of Offshore Wind Turbines FIGURE 5-1 Key components of a wind energy system. of quality assurance/quality control to provide fabrication requirements equivalent to those of CVAs or owners. For consistency of oversight of an offshore wind farm, the scope of the CVA should be expanded beyond what is required by 30 CFR 285. With- out such an expansion, gaps may exist in expected performance similar to those expected with the structural aspects. The scope of a CVA is addressed by 30 CFR 285 in a manner similar to the scope for a CVA in connection with oil and gas facilities addressed by 30 CFR 250, which covers structural and geotechnical aspects for design, fabrication, and installation. Restrict- ing the CVA program to these areas introduces considerable gaps from a systems perspective if balanced risk is an objective. CVAs AND GOAL-BASED STANDARDS The use of goal-based standards is increasing, especially in areas where practice is not mature or there is great variability in design conditions. Offshore wind is a young industry with insufficient prescriptive stan- dards and little operating experience with the environment affecting

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Role of Third-Party Oversight and Certified Verification Agents 105 TABLE 5-1 Comparison of Scopes for Wind Energy and Oil and Gas Facilities Offshore Type Wind Energy, Oil and Gas, Label Item Certification 30 CFR 285 Recommended 30 CFR 250 A Blades Design No Des, fab, inst N/A Des, fab, insta B Control and protec- Design No N/A tion system C1 Generator No No No N/A C2 Gearbox Design No No N/A D Tower and struc- Design Des, fab, inst Des, fab, inst Des, fab, inst tural support E Foundation No Des, fab, inst Des, fab, inst Des, fab, inst F Infield cables No No Yes No (infield flowlines equivalent) Des, fab, instb G1 Electric service No Des, fab, inst Des, fab, inst platform G2 Electric service No No Des, fab, inst No (drilling and platform; trans- processing formers, con- facilities trols, and so equivalent) forth Noc (export H Export cable No No Yes pipeline equivalent) NOTE: des = design, fab = fabrication, inst = installation. a If design basis requires active blade and yaw control to limit loading conditions. b Implied but not explicitly stated. c No for fixed structures; des, fab, and inst for floating structures. the facilities. These conditions are parallel to those in the offshore oil and gas industry during the mid-1970s. The NRC study recom- mended that USGS implement a third-party verification system and an advisory board to assist it in establishing a framework for the CVA program. The use of an advisory board by BOEMRE would be valuable in identi- fying the interrelationship between goal-based standards and more pre- scriptive standards and in establishing the framework for CVA assessment to determine adequacy of design, fabrication, and installation details in meeting the goal-based standards. The use of goal-based standards does not alter the intent or the scope of a CVA; instead, it introduces an additional set of high-level targets that can

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106 Structural Integrity of Offshore Wind Turbines be used by the CVA as a framework providing consistency in evaluating prescriptive standards and elements within a basis of design and the con- struction and installation documents. SUMMARY In the late 1970s, the development of oil and gas facilities in offshore envi- ronments began accelerating in areas posing more severe challenges (e.g., deeper water, earthquake zones, and unstable seafloor sediments) and in areas with little or no historical operating experience. Similarly, in the past 20 years, wind energy facilities in Europe have spread from land to off- shore environments. In both of these situations, regulators have used third-party review protocols to assist in the oversight of design, fabrica- tion, and installation of facilities and to provide a higher level of assur- ance that the interests of the public and the regulations governing these facilities are being met. FINDINGS AND RECOMMENDATIONS FOR TASK II The findings and recommendations for Task II of the statement of task are given below. Findings 1. Wind turbine type certification in accordance with IEC 61400 pro- vides effective oversight and third-party review for a. Design of the nacelle; b. Design of the blades if the type certification criteria match the instal- lation conditions; and c. Design of the tower provided the foundation stiffness matches the design assumptions and specifications of the tower, blades, and nacelle. 2. Type certification does not cover fabrication, transportation, or instal- lation activities. 3. Type certification of blades addresses only design conditions and requires testing of only one blade. There are no fabrication quality assurance/quality control requirements for production.

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Role of Third-Party Oversight and Certified Verification Agents 107 4. The CVA program defined in 30 CFR 250 may be used as a model for offshore wind projects. 5. The regulations of 30 CFR 285 provide a good definition of the role of a CVA. Recommendations 1. The responsibility for proposing a comprehensive set of national and international standards, rules, industry guidelines, and recommended practices (referred to here as a “package of Guidelines”), and the underlying documentation and analysis, should rest with the devel- opers. The CVA’s role should be to review and comment on the ade- quacy of the proposed package of Guidelines in meeting the goals and objectives defined in the BOEMRE goal-based standards. Although BOEMRE should consider the documentation and analysis provided by the developer and the report of the CVA, responsibility for approval of the proposed package of Guidelines and for determination of their conformance with the goal-based standards should rest solely with the agency. 2. The scope of the BOEMRE-mandated third-party review process should include a. Blades, b. Blade controls (if reliance on active controls is required for load reduction), c. Tower and structural support, d. Foundation and station keeping, e. Infield cables and connectors, f. Other structural and electrical systems, and g. Export cables. The third-party review should ensure the following: a. Design: The design adheres to good industry practice, the basis of the design is appropriate for the location and stated objectives of the project, site-specific conditions have been appropriately addressed, and the identified codes and standards are adhered to.

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108 Structural Integrity of Offshore Wind Turbines b. Fabrication and manufacturing: Quality assurance/quality control processes are in place to ensure that fabrication and manufacturing comply with the design and the identified codes and standards. c. Installation: All transportation and field installation activities are performed in a manner ensuring that the facility meets the design intent. The third-party reviewer should provide periodic reports to BOEMRE with regard to the review findings and should note any deviations or concerns. 3. Type certification of a wind turbine may be substituted for portions of third-party design review if the type certificate is appropriate for site conditions (e.g., the IEC wind class). 4. BOEMRE should retain responsibility for final approval. It is essential that BOEMRE have staff competent to select qualified third parties (see Chapter 6) and to approve projects. REFERENCES Gerwick, B. 1977. Verification of Offshore Platform Design and Installation: The Marine Board Panel View. Proc., Offshore Technology Conference, Houston, Tex. Marine Board. 1977. Verification of Fixed Offshore Oil and Gas Platforms: An Analysis of Need, Scope, and Alternative Verification Systems. National Research Council, Washing- ton, D.C.