single-user mitigation banks are two forms of permittee-responsible mitigation; commercial mitigation banks, in-lieu fee programs, cash donation programs, and revolving fund programs are third-party mitigation mechanisms (see Table 5–1).

Central to developing a taxonomy is the definition of mitigation “action.” A compensatory mitigation project consists of distinct actions, including a general design concept, identification of a general watershed location for the project, development of site design plans, development of ecological performance standards (target wetland functions), site acquisition, construction in accordance with design standards, monitoring to determine whether the design is trending toward the target wetland functions, achievement of performance standards, and regulatory certification that a site meets required mitigation requirements. Another distinct stage is an action to assure that the site is protected and managed in perpetuity. With each step the actions taken increase the assurance that the compensatory wetlands will contribute to the ecological values of the watershed.

Much of this chapter is devoted to describing compensatory mitigation mechanisms where a third party (some entity other than the permit recipient) is responsible for each of these mitigation actions. It is important to note, however, that the typical permittee will perform the mitigation itself or hire an agent to perform it, and the permittee remains responsible for the mitigation. For example, the U.S. Army Corps of Engineers (Corps) Headquarters, Operations, Construction, and Readiness Division reports that 75% of the compensatory mitigation required in 1998, under NWP 26, which is no longer in effect, was expected to be implemented by the permit recipient. Nine percent of this mitigation was done at a mitigation bank, and the balance was to be provided through other mechanisms (e.g., in-lieu fees and in-kind exchanges). It is not clear from the data description whether the banks were single-user or commercial; however, in either case, permittee-responsible mitigation is the dominant means for offering mitigation.


On-site mitigation is restoring, enhancing, creating, or preserving wetlands adjacent to an impact site. The Corps and the U.S. Environmental Protection Agency (EPA) define on-site mitigation as mitigation in “areas adjacent or contiguous to the discharge site” (USACE/EPA 1990). When on-site mitigation is not warranted, the agencies state that it should be “in close proximity [to] and, to the extent possible, [in] the same watershed” of the project that is adversely affecting wetlands. The agencies' preference for on-site mitigation is not absolute, however, and does not preclude the use of off-site mitigation when it provides greater environ-

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