Map visualisation service (WMS) of the dataset: Plan to prevent the natural risks of differential settlement (swelling, clay removal) — Perimeter — Department of Tarn-et-Garonne

This dataset contains the boundaries at the different stages of the development of the PPRN. The characteristic of such perimeters is to be the consequence of an official act and to produce their effects from a defined date. This is the following:
— prescribed perimeter contained in the prescription order of a PPR (natural or technological);
— scope of exposure to risks that corresponds to the perimeter regulated by the approved RPP. This approved perimeter is a utility easement (PM1 for PPRNs and PM3 for PPRTs);
— scope of study which corresponds to the envelope in which the hazards were studied.

本数据集涵盖了PPRN在各开发阶段的边界范围。此类边界的核心属性为：由官方行为所确立，并自指定日期起产生法律效力。具体如下：
— 自然或技术型PPR的审批令中载明的法定边界；
— 经批准的RPP所规制的边界对应的风险暴露范围；该获批边界属于地役权范畴，其中PPRN对应PM1，PPRT对应PM3；
— 研究范围，即开展危险源研究所覆盖的空间范围。