Geotechnical Conditions of Mining Waste Dumps – A Necessary Investigation for their Reintegration into the Surrounding Landscape: A Case Study from Jiu Valley (Romania)

The waste rocks deposited in the dump that served the Jiet shaft is unsuitable for the installation of vegetation, so that, at present, the deposit makes a discordant note with the surrounding landscape, producing chromatic and aesthetic disturbances. Coal mining activity in Jiu Valley is approaching, faster than expected a few years ago, to its end and one of the main directions for transforming the area (while ensuring its sustainability) is the development of tourism. Under these conditions, a problem that has remained partially unresolved is related to the integration of the former mining perimeters, especially the waste dumps, into the surrounding landscape. Such an approach must always start from a thorough check of the technical condition of these artificial earth constructions. For this reason the stability of the dumps in the Jiu Valley is considered to be an important issue, considering that possible failures endanger both the natural and the anthropic environment. In the case of the Jiet waste dump considered as a case study, because several years have passed since the last sterile rocks were deposited and since stability studies were performed, a new such study was considered necessary (given that the deposited rocks underwent certain changes: compaction, mechanical disintegration, chemical alteration, etc.). This paper presents the results of the stability analyses carried out during 2022 and a series of conclusions regarding the limits within which the geometric elements must be framed so as to ensure a good stability reserve and thus allow the ecological restoration works to begin.