In the initial stages of planning for the construction of a natural gas pipeline, Stanley Consultants identified a 13 x 2 mi corridor within which alternative routings would be selected. They contracted with EarthView Environmental, Inc. (EVE), to gather information on the known and likely location of archaeological sites within this corridor, to allow planners to identify routes least likely to encounter significant archaeological sites.
In Iowa, this initial data-gathering effort is called a Phase IA survey, and its purpose is to assess the need for, and planning of, a Phase I field survey. EVE was well-positioned to offer this service. Our expertise in GIS allowed us to overlay many kinds of maps and map data, giving Stanley Consultants a clear overview of high- and low-risk areas.
This project is typical of the range of information sources that EVE considers in Phase IA surveys:
Sites and survey areas from I-Sites, a statewide archaeological GIS.
- The on-line National Register of Historic Places.
- LANDMASS, a model of archaeological site potential.
- Historic maps, from the earliest 1830s-1850s land surveys to township plats from 19th-20th century county atlases.
- Historic aerial photographs from the 1930s forward.
- SSURGO soils and STATEMAP geological maps showing terrains where archaeological sites are likely to