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18 A Guidebook for the Evaluation of Project Delivery Methods Table 2.1. The timing of project delivery method selection. Project At the end of At the end of At the end of delivery conceptual preliminary Construction final design method design engineering DBB NF CMR NF DB NF NF DBOM NF NF = Desirable = Feasible NF = Not feasible use alternative project delivery methods, the level of competition in the market, and the permits needed for the project. Lifecycle issues cover the costs of maintaining and decommissioning the facility and the ability to minimize the energy and environmental effects of the project. In the parameters mentioned above, the ability to transfer the risks of a project to entities other than the owner is a characteristic that is related to both the project and the owner agency. This parameter includes the level of risk and uncertainty of the project and the ability of the owner to assume the risks or transfer them (risk-averse or risk-prone agency). Project delivery methods have different mechanisms for risk distribution among the entities involved. In summary, the existing body of knowledge in the area of project delivery, along with specific information col- lected on transit projects during interviews, provides a solid foundation for developing a new selection system for project delivery methods that is tailored to the needs of transit owners. Timing of Project Delivery Method Selection Transit projects, especially those that receive federal funds, follow several steps during their development. These steps can be summarized as follows: Alternative Analysis--Draft Environmental Impact Statement (AA/DEIS), Final Environmental Impact Statement (FEIS), and Full Funding Grant Agreement (FFGA). The first two steps roughly coincide with conceptual design (5 to 15% of the design effort) and preliminary engineering (25 to 30% of the design effort). The timing of the FFGA, which repre- sents the federal government's commitment to fund the project, depends on the project deliv- ery method; the FFGA can come at the end of preliminary engineering or at final design. In selecting a project delivery method, the owner should realize that the window of opportunity to select some methods will close as the project moves through various stages of development. Table 2.1 maps project delivery method selection with project development phase. It can be seen that selecting a project delivery method other than DBB should be done relatively early. Most of the benefits can be realized by engaging the constructor as soon as possible. The decision point for project method delivery selection should not be confused with the time that the constructor is engaged. As an example, an owner may decide to engage a DB contractor at the end of preliminary engineering or even later in order to clarify the project scope and reduce the uncertainty. However, the owner should have decided on the type of delivery (e.g., DB) much earlier, so that the design documents can be developed to properly accommodate the type of delivery method.