Incorporating Cultural Resources in Design for Habitat Mitigation (submitted in coordination with TRB's AME-60 committee)
Environmental Considerations in Planning
Research Idea Scope
Transportation projects frequently require mitigation for impacts to natural resources, such as wetland, stormwater, pollinator and reforestation sites per regulatory requirements. Transportation corridors are often located in highly developed areas of states, where site selection can be limited and costly. Another factor in limiting site selection is the presence of historically significant archaeological sites, or areas of archaeological potential (often in the same locations for high-value habitat). For such sites, archaeological evaluation is necessary, and impacts to sites must be avoided per other requirements such as Section 106 of the National Historic Preservation Act. This proposal seeks to identify means and methods for mitigation activities such as wetland buffer and reforestation, that can be accomplished with limited ground disturbance, in ways that do not cause impacts to archaeological resources. It is a truism that plants and trees grow naturally on archaeological sites and do not destroy them, yet agencies are often in the position where deliberate plantings are considered a potential impact to protected archaeological sites. Identifying best practices, with the ultimate goal of a guidance document that jurisdictional authorities could agree to, would increase available mitigation opportunities while maintaining integrity of historic and archaeological resources.
Areas of research would include plant palettes for various broad ecological regions; planting and invasive species removal methods that limit impacts to archaeological integrity; and evaluating a variety of common geologic/natural site types to ensure broad applicability. The common activities involved in habitat mitigation design and implementation will be evaluated against concrete data from archaeologists, geomorphologists, soils scientists, and foresters about how soils move or change under different types of planting and maintenance regimes. Ultimately, the research will provide a document recommending practices to facilitate selection, design, and construction of habitat mitigation where impacts and adverse effects to any archaeological resources would be avoided through implementation of recommended principles.
Urgency and Payoff
The urgency of this effort is significant with increasingly limited site selection options; cost savings would derive by limiting the need for archaeological survey and “mitigation for mitigation” situations where Section 106 mitigation is required to implement mitigation for other resource types. A robust toolkit for design and construction of archaeologically-sensitive habitat mitigation would reduce schedule and risk for projects requiring development of natural resources mitigation sites. By demonstrating successful practices that can be replicated by other state DOTs and transportation agencies, cultural resources and historic properties are better integrated into habitat mitigation planning.