Soil and foundation work is integral to most projects, whether facility projects led by architects or other projects coordinated by engineers. Often a specialist will be involved, especially early in the planning and design phase, as a subconsultant to the design professional. Note the position of subconsultants in our various relationship charts in Chapter 2. If a building is being planned, the geotechnical specialist might be engaged to advise on dealing with earthquake susceptibility, soft sediments, alternative foundation solutions, unstable slopes and flooding potential. If the design professional is planning and designing a roadway, geotechnical expertise might contribute studies of environmental impacts, frost-heave potential, erosion control, embankment and base course material source evaluation and slope stability.