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Geomorphic-based mine restoration of clay quarries in Tortosa (Catalonia) was co-funded by the European Union’s LIFE programme. The landform design was made with GeoFluv-Natural Regrade. Their buil...

Fluvial geomorphic approaches for reclamation landform design have been applied since 2000, mostly in mined lands, as an alternative to conventional landform design methods. Those approaches aim to reconstruct mature landforms and drainage networks that would develop within a natural catchment, after thousands of years of work performed by geomorphic processes. Some fluvial geomorphic design methods take specific measurements from natural and stable reference areas for initial input values for reclamation design. Valid reference areas can be difficult to find, can be in highly anthropized environments, or may be difficult to access. This paper evaluates the use of remote sensing tools to measure morphometric parameters in upper sections of agricultural land catchments considered for use as reference areas. The ridge to head of channel distance (Xrh) was the parameter of interest. We used land surface profiles developed from LiDAR (Laser Imaging Detection and Ranging) data and planimetric measurements from orthoimages to estimate Xrh. The results obtained by the two methods were encouraging but showed a significant difference. Ground truthing showed that ploughing obliterated between 19.5 and 22.4 m (on average) of the headwater section of first-order channels, reducing the channel length by 15.1 to 32.4%. Using a greater Xrh value than appropriate for near steady-state conditions as a design input for a geomorphic reclamation project would be expected to result in active erosion processes in the constructed reclamation to regain their missing channel length. We recognize the advantages and limitations of remote sensing methods for measuring the morphometric parameters of the landform relief design inputs. We show how these tools may be used to help select and prioritize reference areas, and warn about the use of disturbed landscapes as reference areas to assure the geomorphic stability of the constructed reclamation designs.

The research on tailings deposits regarding geomorphic approaches, aeolian activity and integrated physical–chemical dynamics and instability is almost inexistent. This work performs such analysis at the San Quintín Mine site, located on the Alcudia Valley region of central-south Spain. The first evidence of mining activity on San Quintín goes back to 1559 and the last one to 1988. The mine activity here produced two very different deposits. ‘Old tailings’ correspond to early concentration procedures between 1889 and 1923. The resulting piles look chaotic and the tailings vertically and laterally alternate with rock wastes. These deposits have been eroded, mostly, by fluvial processes. ‘Modern tailings’ deposits correspond to more efficient froth flotation treatments, between 1973 and 1988, when part of the old tailings were reprocessed. The grain size of these latter tailings is more homogenous, mostly sandy, which favour intense aeolian erosion. By means of a detailed inventory, we were able to identify and catalogue both fluvial and aeolian landforms, along with those produced by weathering or mass movement. We also quantified aeolian erosion, obtaining a single net wind transport rate of 12.6 t ha−1 year−1, related to WSW winds. From an understanding of the geomorphic activity of the mined area, we propose guidelines for the restoration and remediation of the site, comprising wind erosion prevention measures for the modern tailings and physical stabilization through geomorphic restoration for the old tailings, combined with chemical remediation measures that have been proved useful on similar cases: open limestone channels connected to constructed wetlands., This study has been funded by: (1) Project CGL2015-67644-R (Spanish Ministry of Economy and Competitiveness) (2) The Ecological Restoration Network REMEDINAL-3 of the Madrid Community (S2013/MAE-2719).