CALARUSSO REPORT ENVIRONMENTAL RESTORATION IN CALARUSSO MINE

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1 CALARUSSO REPORT ENVIRONMENTAL RESTORATION IN CALARUSSO MINE

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3 1. 1 ENVIRONMENTAL RESTORATION IN CALARUSSO MINE 1.1 Introduction The company Dolomite Franchi S.p.A., carries out mining activities for the extraction of dolomite in the Calarusso mine in the municipality of Zone. Photo 1 panoramic view of Calarusso mine The Calarusso quarry belongs to the category of hillside mines, subtype amphitheater. In case of such a mine, the visual impact is high because the surface is also visible from afar. For this reason, the surface is being restored through reforestation measures of the northeast abandoned terraces, also supported by bioengineering actions, already implemented in the mine, as part of a project providing for the creation of appropriate conditions for reforestation through the supply of soil and water in the critical summer period. The restoration and reforestation measures have been carried out according to the Restoration Project of Calarusso Quarry approved by the Region with Decision n of CALARUSSO REPORT 3

4 1.2 Restoration measures The final environmental restoration of Calarusso is carried out as follows: Gradual restoration of the abandoned terraces after cleaning them of precarious rocks; Artificial ageing (oxidation) of the terraces through oxidizing solutions; Restoration of the abandoned terraces through supply of soil; 1.3 Reforestation measures For the reforestation, both native trees and tree-shrubs are used. In order to make the terraces look less geometric and unnatural, reforestation units have been located only in some parts of the rocky surface, thus allowing an optimization of the water supply that must be concentrated in specific and confined areas. The features of the trees to be used must be carefully evaluated as they are of crucial importance for the success of the reforestation, e. g. trees of 1-3 years must be used. The planting density varies from 1,000 to 1,200 trees per hectare. The best planting period is from autumn to the end of winter; freezing periods must be avoided. 1.4 Maintenance measures Restraint of the invasive vegetation Weed control must be carried out on a timely and constant basis, above all during the first year after planting. Irrigation A serious problem that reforestation is faced with in this area is the summer drought: in July, in particular, few rainfalls together with high temperatures result in water shortages for the trees. A useful solution is thus to leave a slight wedge around the trees, allowing a greater accumulation of water near the roots. Fertilization Trees and forest tree-shrubs do not have high nutritional requirements. Only a few tens of grams of a ternary fertilizer at the bottom of the hole are necessary in the first growing phases of the tree. Over the years, forest soil improves its own fertility thanks to the rich supply of organic substances coming from the yearly fall of leaves. Protection from parasites All the above-mentioned techniques help protect the trees and tree-shrubs against parasites. However, specific measures also have to be taken to protect them from game and hare.

5 2. ENVIRONMENTAL RESTORATION MEASURES IN 2013 In June 2013, Dolomite Franchi S.p.A. started important environmental restoration measures on the abandoned terraces in two phases: 1. Artificial ageing (oxidation) of the abandoned drop 2. Creation of green units or green islands. 2.1 Artificial ageing (oxidation) of the abandoned sides A rock chromatic mitigation technique was used, with fast artificial oxidation of the vertical sides with the aid of natural pigments that naturally accelerate the natural ageing process of the fronts of previous excavations. The operation took place between June and October The first part of the work, carried out in late June, was to test the oxidizing solution in order to find the right shade of color to the rock. The oxidation process was carried out by specialized enterprises with specific pumping equipment and spray lances. It began in the upper part of the front, progressing gradually towards the square below (photo n. 3) and was performed in a total area of 30,000 square meters. Photo 2 Men at work (artificial ageing) CALARUSSO REPORT 5

6 Photo 3 Abandoned quarry faces during oxidation (September 2013) Photo 4 Artificial ageing completed (December 2013)

7 2.2 Revegetation The operation of revegetation required two different actions: 1. Creation of the first 2 green islands, of 9 planned, by planting of tree and shrub species: first 640 trees with a maximum height of 2.5 m were planted; in the second phase 15 plants having a height of 5 m were planted. Photo 5 creation of green island 2. Planting of 600 climbing ivy trees (Hedera Helix quality). The shrubs of 1.2 m height were placed on all the steps, trying to affect more areas with less vegetation, thus the complete coverage of the mining walls. CALARUSSO REPORT 7

8 Photo 6 Ivy plants placed on site

9 3. ENVIRONMENTAL RESTORATION MEASURES IN 2014 AND 2015 Photo 7 East side of mine one year after the artificial ageing After the main interventions in the year 2013, the environmental restoration measures in the Calarusso mine have been continued mainly by carrying out the activities required by the mining authorization, especially in the lower part of the mine, which was excavated. The main activity included the gradual restoration of the abandoned terraces after cleaning them of precarious rocks, through the supply of new soil on the abandoned terraces for the planting of trees, shrubs and manual sowing of herbaceous species in mixture. Moreover, extraordinary works were necessary for the maintenance of the green islands created in These works included the replacement of all trees and bushes damaged in the first two years after planting, especially in the last warm summer months. CALARUSSO REPORT 9

10 Photo 8 West side of mine Photo 9 Aerial picture of Calarusso mine

11 Alessandro Romano Plant manager Massimo Pavarani Head of mining Paolo Cadorin Environmental management Photo 10 Green island today CALARUSSO REPORT 11

12 05/ 2016 EN RHI AG, Wienerbergstraße 9, 1100 Vienna, Austria, phone: , fax: , DOLOMITE FRANCHI SPA, Via Corsica 14, Brescia, phone: , fax: ,