ERO conducts all phases of Section 106 compliance, including: 

• Identification (Class I data syntheses, reconnaissance survey, and Class III intensive surveys)
• Evaluative testing of archaeological sites (Phase II) for significance
• Historic property treatment for adverse effects (Phase III), including excavation and Historic American Building Surveys (HABS) and Historic American Engineering Records (HAER) documentation

Federal undertakings require that agencies consult with Native American tribes to further identify and consider the effects on culturally sensitive resources. ERO has assisted federal and state agencies with this requirement by identifying tribes with historical affiliation to an undertaking's APE, conducting or facilitating consultation on their behalf, and facilitating meetings for the purpose of consultation.

ERO provides Historic American Building Surveys/Historic American Engineering Records Documentation (HABS/HAER) and Historic Resource Documentation under both National Park Service and state standards. HABS/HAER documentation is typically performed as part of a treatment plan to mitigate an adverse effect on a historic property, and includes high-quality photo documentation, a narrative history compiled through primary and secondary archival research, and measured drawings. ERO has completed HABS/HAER documentation for historic bridges, engineered elements of canals and ditches, buildings, and features of designed landscapes.

Using Geographic Information Systems (GIS), ERO conducts predictive modeling using environmental data layers and archaeological site data to estimate the location of both surface and buried sites. Predictive modeling is especially useful during NEPA analysis when identification surveys are premature, but a reasonable estimation of resources is an expected outcome of the analysis. In dynamic landscapes such as alluvial settings, predictive modeling has the capability to estimate the number of buried archaeological sites that might be expected during construction of buried pipelines, for example.

ERO uses remote sensing techniques to identify buried cultural resources, including unmarked graves and archaeological sites. Geophysical applications (ground penetrating radar, resistivity, and magnetometer) can locate buried cultural resources that are previously unknown, or quantify the extent, number, and depth of known resources. Remote sensing serves to focus mitigation efforts over large archaeological sites by maximizing time and limiting expense.

ERO specializes in architectural documentation, condition assessments, and stabilization of prehistoric standing structures. Ruins preservation is generally a four-step process that requires documenting existing conditions, completing a condition assessment that identifies threats and recommends treatments, stabilizing architecture, and developing a monitoring plan to assess conditions over time. Architectural stabilization is intended to stop or slow down the deterioration of the structural remains and retain the original architectural fabric and integrity as closely as possible. For example, ERO performed ruins preservation at the Moon House complex and in Grand Gulch in southeast Utah.

• Permitted with all federal and state agencies in our core service area of Colorado, New Mexico, Utah, and Wyoming
• Tribal permits include the Southern Ute Indian Tribe and the Navajo Nation
• Forest Service Permits with Rocky Mountain, Intermountain, Northern, and Southwest Regions
• Prequalified contractor for the Bureau of Reclamation, National Park Service, and Bureau of Indian Affairs
• ERO routinely works with the U.S. Army Corps of Engineers, the Bureau of Land Management, and engineering companies. We hold indefinite delivery/indefinite quantity contracts with the Federal Highway Administration-Central Federal Lands, Denver Water, Colorado Springs Utilities, La Plata County, and the National Park Service.