Due to the need of current studies on the Permanent Preservation Areas (APPs) for the county of Alegre - ES, it is proposed in this study to demonstrate how the use of Geotechnologies can help in an effective way to map those areas, helping to understand the areas to be preserved in the county. The study was accomplished in the whole county of Alegre - ES which objectives were: a) to elaborate analogical and digital maps of the county, with the aid of Geotechnologies; b) to delimit the Areas of Permanent Preservation in the optics of the Environmental Legislation and c) to emphasize the importance of identifying the areas in an automatic way so that it can implant environmental projects that seek to promote actions in search of a maintainable relationship between man and environment in a more efficient way. The county of Alegre has an area of 336,39 km² of APPs (43,50% of the total area of the county). The methodology for automatic delimitation of APPs was efficient, indicating that the same, around of spring (buffer of 50 m), in the hillsides with steepness superior to 45 degrees, hill top (superior third of hills) and margins of the courses of water (buffer of 30 m) they acted respectively 9,86 km² (1,27%), 8,99 km² (1,16%), 237,35 km² (30,69%) and 95,11 km² (12,30%) of the total area of the county.
APPs; system of geographical information; environmental legislation