LANDWORKS Sardinia presents
ARGENTIERA
LANDWORKS Sardinia 2015, operative workshop, 21st - 31st May, ARGENTIERA (UNESCO heritage), Sardinia, Italy. The fifth edition of the workshop will be held at the abandoned site of the Argentiera, an old mining complex along the coast north-west coast of Sardinia. The site is part of the Historical and Environmental Geo-mining Park of Sardinia, a part of the Global Network of Geoparks of UNESCO, a network of territories recognized as to be preserved because of their particularly significant geological heritage, a heritage that is thanks to the “scientific rarity, aesthetic and educational value� of their sites and artifacts. Thanks to the conservation of the historical ancient silver extraction structures found on site, the area has been well preserved through time. Along with its exceptional geographic character, the mining settlement of Argentiera is like a museum of natural history. The site is unique and summarize the entire anthropological history of Sardinia, an island that since ancient times has been a basin of extraction of metals and coal for the whole Mediterranean area.
LW 2015
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA SARDINIA
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3 LW 1 2 3 4 5 6 7 8
SASSARI ALGHERO PORTO TORRES STINTINO CASTELSARDO TEMPIO OZIERI PORTO CONTE
LW ARGENTIERA
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7 8
2 03
Administrative office 15
Director's Villa 27
Bar_after-work miners
Santa Barbara Church
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16
Cantina
PIAZZA M. CAMILLO
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26
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Kindergarten
4 19
17
25
PIAZZA CANTINA
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3
8 25
13
1
MAIN BEACH Cinema
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2
Washery
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2
6
SMALLER BEACH
9 7
Podestà Shaft
Strada di Mezza Costa
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11 10 6
Edifici produttivi | Industrial buildings 1_Laveria | Washery 2_Magazzino | Storehause 3_Officine | Laboratory 4_Falegnameria | Woodwork 5_Cabina elettrica | Eletrical workshop 6_Bacino | Pond 7_Pozzo Podestà | Podestà Shaft 8_Forge 9_Compressori | Compressor 10_Stalla | Stable 11_Segheria |Sawmill Edifici pubblici | Public buildings 12_Scuola elementare | Elementary school 13_Scuola | School 14_Albergo operai scapoli | Hotel workers 15_Uffici Amministrazione | Administrative office 16_Chiesa Santa Barbara | Santa Barbara Church 17_Asilo | Kindergarten 18_Cinema 19_Infermeria | Infirmary 20_Dopolavoro minatori | Bar_after-work miners 21_Ufficio Postale | Post Office 22_Guardia di finanza | Finance police 23_Rimessa | Garage 24_Circolo impiegati | Employees circle 25_Uffici | Office 26_Cantina | Shop Abitazioni | Homes 27_Villa del Direttore | Director's Villa
CALA DELL’ARGENTIERA
BELVEDERE
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
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picture by Archivio Storico Minerario - IGEA SpA
... «Per andare in miniera bisogna scendere. Sottoterra. All’imbocco del pozzo si lasciano il sole e le nuvole, i boschi e le pernici. Si lasciano le mogli e i figli. Solo Dio, forse, ci si porta appresso nella parte più intima di noi se anch’Egli non ci abbandona laggiù fuggendo la materia più profonda. Nel terribile mondo della roccia e del buio sopravvivono solo uomini di roccia e di buio che hanno necessità di dimenticare la coscienza di essere uomini che, se li coglie nel buio del lavoro, li spinge nel pericolo della fuga o della ribellione. Da questo la necessità di riconoscersi, nelle otto ore di lavoro, materia pura ri-mandando l’umanità alle ore del riposo, all’incontro, ogni giorno meraviglioso e inaspettato, con la moglie e i figli» ... BETH-GER: IL LUNGO DOLORE, Manlio Massole
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
The argentiferous galena deposits of Argentiera, exploited since Roman times, are situated on the coast of the Nurra district in north-western Sardinia, in the Municipality of Sassari. In the early years of the 19th century the site achieved a certain notoriety when it attracted the interest of the great Honoré de Balzac in the hope soon shattered - of making a fortune. Modern industrial mining at the site was started in September 1867 by its first concession holder, Marquise Angela Tola di San Saturnino. Harried by operational problems and poor returns, in 1870 she sold the mining license to the “Société Anonyme Minière et Métallurgique Sardo-Belge”, followed in 1872 by the “Compagnia Generale delle Miniere”. Under the new concession holders, the mine’s output increased considerably, especially thanks to skilled engineers such as Eugenio Marchese. The galleries were extended and internal logistics was improved; moreover, near the ore processing plants, a small
village was built, including housing and basic services for the several hundred families of miners and technicians. A pier was also constructed in the bay of San Nicolò for loading the ore onto the ships. In 1886 the mine was acquired by the Società di Correboi whose owner, Genoese financier Andrea Podestà boosted its production and above all improved both its industrial and housing facilities. In 1924 the Correboi company came under the control of the italo-French Company Pertusola which managed until 1963, when it was closed down due to depletion of the deposits. Seen from above, in this fine panoramic view, the Argentiera is a clear example of a place where home and workplace were located close to each other. This indeed was the choice in most mine sites, as very often, as in this case in the Nurra - they were set in isolated and inhospitable areas. The idea was that the miners - who had 07
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picture by Archivio Storico Minerario - IGEA SpA
Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
no means of transports, should be able to reach their workplace rapidly and without effort. The glittering blue of the sea and the dark green od the Mediterranean scrubland surround and frame this mining complex. Against them, the dull colours of the rubble and slag strike a discordant note, and are a significant testimonial to how mining activity was wont to transform and mark - not always happily but certainly deeply - natural landscapes. The Argentiera is one of the historic mines of the island, not only because its origins go back thousands of years, but because in modern times its history was shaped by bussinessmen and engineers of various nationalities and alternating fortunes. Seen from above, the mining complex and the miners’ village overlooking the splendid bay of San Nicolò form an interesting unitary insdustrial 09
picture by Archivio Storico Minerario - IGEA SpA
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
development showing the international influences which mark the island’s mining sites. The sequence of Belgian, Ligurian, French and Sardinian businessmen, engineers and miners made this site - set at quite distance apart from the nearest towns and villages (in view of the means of transport of the time) - a unique melting pot of different cultures and lifestyles. It is said that one French engineer, assigned to Argentiera by his Company, wrote to his Director in Paris saying that living and working here meant experiencing together the paradise of a fascinating nature and pleasant environment and the hell of an underground world which was treacherous and full of constant dangers. (source: Gianni Alvito_Landscape and mines of Sardinia from above)
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picture by Archivio Storico Minerario - IGEA SpA
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
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picture by Archivio Storico Minerario - IGEA SpA
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
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picture by Gianni Alvito_Landscape and mines of Sardinia from above
Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
THE MINING SITE: everything yuo need to know Cala dell’Argentiera” (Argentiera Cove) is the natural setting of the late 19th-century mining village of the same name that was built on a small bay and equipped with a dock. The Argentiera mine was exploited for its rocky foundation which was rich in lead, silver and zinc until 1962, the year in which it was closed. It is currently an exceptional example of industrial archeology. The argentite mountains skim the coastline that opens up onto two spacious beaches. The sand, which is a mix of gravel and mineral dust, causes silvery reflections on the extraordinarily clear sea, creating a spectacular play of lights. The recovery of the historical and environmental value is an excellent opportunity to encourage the development of tourism in the area. This is precisely the purpose behind some redevelopment projects for moving the mining waste to a new facility and amphitheater, which will also improve beach access. A former mining site such as Argentiera shows evidence of its past
extraction and processing phases. The accumulation of waste materials from extraction and processing in areas prone to erosion (rain and storms) over the years has led to concentrations of metals in soil and water that are higher than in surrounding areas. These concentrations are not to be found in adjacent areas such as, for example, Porto Palmas. Activities currently underway – analysis, monitoring and annual sampling for traces of iron, copper, cadmium, arsenic, mercury – and those that are still in the planning phase will allow for unlimited use of the territory and the safeguarding of citizens’ health and safety.
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(source: www.comune.sassari.it)
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CALA DELL’ARGENTIERA MAIN BEACH
2 1 Cinema Albergo operai scapoli Asilo
SMALLER BEACH
Chiesa S.Barbara BELVEDERE Scuola elementare Laveria
Uffici amministrazione
PIAZZA M. CAMILLO
Dopolavoro minatori Villa Direttore
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
RECOVERY AREA AND SAFETY MEASURES: Comune di Sassari 1_BACK BEACH PLAZA
INVESTIGATION CARRIED OUT: Anlyses of random samples have revealed concentrations of lead. INTERVENTIONS: The area will be delimited so as to guarantee static support to the build-ups. With an eye to visual and environmental impact, the intervention will include creation of a mixed containment system made of concrete and stone paneling below a new amphitheatre-like facility.
DESCRIPTION: To the back of the beach, along the side of the driveway leading to the strand, can be found an area originally meant for the movement of material along a railway. Nowadays there are still debris from the old facilities, slag heaps and retaining walls with the upper sides in some points excessively inclined. INVESTIGATION CARRIED OUT: Analyses of random samples have brought to light traces of antimony, lead and cadmium only on the surface. INTERVENTIONS: In light of the location, as well as inherent characteristics and usages allowed for by urban zoning plans, the area may be delimited by waterproof barriers and through the rendering secure or redevelopment of embankments.
3_ BEACHES AND BACKLYING NATURAL SLOPES
DESCRIPTION: Sandy and dark-colored beach area, divided into two portions by a mining-era building. Access to the larger beach is via a natural, and in some parts, steeply inclining slope covered by low vegetation. INVESTIGATION CARRIED OUT: Presence of iron in the natural composition of the shore, as well as traces of lead and antimony. INTERVENTIONS: In light of the limited presence of mineral concentrations lower than the at-risk threshold, the site has not been deemed worthy of reclamation.
2_ BUILD-UPS OF RESIDUAL MATERIALS
DESCRIPTION: Build-ups of mineral refuse materials are unstable and located to the back of the beach. There are ruins of a concrete amphitheater that is at risk of collapsing.
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picture by Gianni Alvito_Landscape and mines of Sardinia from above
Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
PODESTÀ SHAFT: center of production activity In 1868 in the Statistical Report for the Kingdom of Italy, Argentiera is indicated as a producer of galena and sphalerite (more limestone and lead carbonate). The docking port for the merchandise was in Porto Conte and it was from there that the mineral was shipped to Antwerp. In 1870 there were three main shafts: Rietto (30 meters in length), Calabronis (50 meters), the oldest, and the Superiore (70 meters). In 1883 in the Review of the Mining Service, the mine was cited as including the Mare and the Podestà, which was excavated from the bottom of the shaft of the same name and made it possible to reach the deeper parts of the deposit. When it was no longer possible to reach deposits with the shafts, it was then necessary to dig or deepen the vertical shafts, which were equipped with cages for the transport of the miners and materials. The Podestà shaft - which was named after the baron Andrea Podestà, president of the Società Correboi – was the main one and was in the process of being modernized until 1911. It was equip-
ped with steam-powered extraction machinery (considered cutting edge at the time) with a 15-horsepower Humboldt motor, whose vapor was generated by two boilers. The center of production activity of the mine was located in an area between the Podestà shaft and the “washery”, a route stretching 300 meters that the extracted mineral was transported along via railway in a hopper, all the way to the processing plant. In the early 1900s, the mine numbered over 300 employees and the mineral was no longer sent to Antwerp, but to the Italian peninsula. With the outbreak of World War II and after various other vicissitudes, the mine ceased activity.
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(source: www.comune.sassari.it)
PIAZZA M. CAMILLO
Dopolavoro minatori Villa Direttore
Strada di Mezza Costa
1_area nord
2_area est PodestĂ Shaft
Cantina PIAZZA CANTINA
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
RECOVERY AREA AND SAFETY MEASURES: Comune di Sassari 1_SQUARE TO THE NORTH OF “POZZO PODESTÀ” (Podestà Shaft)
2_SLAG HEAPS EAST SIDE
DESCRIPTION: Portion of land sloping toward the road, covered up in heterogeneous vegetation. On the east side, across from the Podestà shaft lies a limited accumulation of mining waste near a stone outbuilding, which may have been used for loading vehicles. INVESTIGATION CARRIED OUT: Analyses on survey samples found concentrations of metal higher that the risk threshold. INTERVENTIONS: Removal of the limited quantity of the slag materials on the side, the heap in the square opposite to subject to reclamation and landscaping of the cleaned-up areas.
DESCRIPTION: A flat plain area near the Podestà shaft building. The ground is paved with gravel made up of mining extract materials. The area, which is completely absent of vegetation, is identifiable in the portion of land between the building and the electric cabin. The area, which has recently been renovated, has some areas with waterproof paving made of building concrete. INVESTIGATION CARRIED OUT: Analyses on survey samples found traces of lead and iron. INTERVENTIONS: Containment in the areas around the built-up areas, creation of waterproof paving whose style is consistent with pre-existing one. Reclamation through phytoremediation: through phytoredemptive properties of plants excess metals present in the soil are extracted, thereby helping them reacquire their original function. The purpose of these interventions is also recovery of the land for educational purposes. Pilot project created through University of Sassari.
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picture by Gianni Alvito_Landscape and mines of Sardinia from above
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
THE “WASHERY” AND THE “HILLSIDE ROAD” During its century of mining life, Argentiera had reached its peak population of 2,000 people, many of whom worked in the mineshafts. With the closing of the mine, Argentiera was completely deserted (today the most populous area is La Plata, which lies at the entrance of the town) and is now a breathtaking site of abandoned buildings such as the old Laveria (“Washery”, or processing plant), the Dopolavoro (“Workers’ Recreation Association”), the Podestà and Alda shafts. Behind the washery can be found blacksmith and carpenter workshops. The mine began as an open quarry and further extended into shafts hewn out of the mountainside from the outside inward in order to reach the mineral deposits. The material coming from the mine was generally mixed up with extraction waste materials of the rocks containing the lode. In order to make it commercially viable, it had to be separated from the ore and then “enriched.” In the early days of the mine, this “enrichment” was performed by women
and children through “hand selection” from the pile of rocks of the blocks rich in minerals for the separation process. At the end of the 1800s, this process was executed in the facility known as the “washery”, in which the minerals were seprated for washing, thus exploiting the differences in weight between minerals and non-mineral rocks connected to them. The washery processed 42-45 tons of raw materials per day, producing 18 tons of marketable mineral per day. The raw slag from this process was placed in a dump, whereas the mud from the washing process, normally deposited in settling vats, was dumped directly into the sea. The concentrated mineral was loaded onto vessels docking at the San Nicola beach (large beach) and transported to Porto Conte, where it was shipped along routes to the ports of Northern Europe. (source: Luciano Otelli - Argentiera: the field, the mine, the men. )
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(source: www.comune.sassari.it)
Cinema Albergo operai scapoli Asilo
SMALLER BEACH
Chiesa S.Barbara BELVEDERE Scuola elementare
1
Laveria
Uffici amministrazione
2 PIAZZA M. CAMILLO
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Dopolavoro minatori Villa Direttore
Strada di Mezza Costa Strada Mezza Costa
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
RECOVERY AREA AND SAFETY MEASURES: Comune di Sassari 1_ THE WASHERY AREA DESCRIPTION: The area surrounding the building “Washery” has clay flooring and a containing wall made of mine slag. INVESTIGATION CARRIED OUT: Analyses on survey samples found traces of lead. INTERVENTIONS: Containment in the areas around the built-up areas, creation of waterproof limestone paving in the plaza areas and green covering of the heaps located behind the retaining wall. The intervention will necessarily call for re-routing of waterways and the collection of water coming from the slope, as well as the structural consolidation of the containment structures.
found concentrations of metal higher than the risk threshold. INTERVENTIONS: Mouldings for the safety of banks below. 3_ DOWNSTREAM SLOPE DESCRIPTION: Steeply inclined slag heap, which later was to become the foundation for a gravel road cut into the hillside leading to the sea dumping areas. The mountainside has a steep slope and the retaining structures at the foot of the hill – which were made in various periods so as to accommodate increasingly large volumes of material – are beginning to show their unsuitability, especially in relation the dwellings located in the immediate area. INVESTIGATION CARRIED OUT: Analyses on survey samples found traces of lead. INTERVENTIONS: The site has been rendered safe with the retaining of mining extraction material through waterproof paving along the base of the road. Vegetation on the surface covering in the valley wall. Rerouting of waterways coming from the mountainside, reshaping of the cliffs and structural consolidation at the base of the cliff.
2_UPSTREAM SLOPE DESCRIPTION: The sloping side toward the road cut into the mountainside, covered in heterogeneous vegetation and on the surface minute pieces of rock coming from the cleaving of schists. On the slope are found some buildings with access to a road built onto a terraced hill made up of heaps of slag material. INVESTIGATION CARRIED OUT: TAnalyses on survey samples 27
picture by Gianni Alvito_Landscape and mines of Sardinia from above
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
THE MOUNTAIN SIDE AND THE SEA VIEWPOINT Unemployment during the war hit Argentiera particularly hard, which was far from inhabited centers an from the most important mining sites of the island. It was possible in any case to sell and send all of the material that had been previously produced and in storage in the plazas of the washery. In November 1916 over 9,000 tons of sphalerite was sent to the United States, 1,900 tons to Great Britain and a steamer was expected to take 2,500 tons of it that had already been sold in Holland. This all took place at the docks of the harbor in San Nicola (whose remains are visible between the two beaches), where ended the route on rails of the carts loaded with minerals. During the winter season the transport by sea was made impossible because of the heavy sea and by the restrictions to the coastal navigation due to the state of war. The whole production was trucked to the Porto Torres port. While the minerals were sold, the waste rock was stocked in dumps. The so-called Belvedere is one
of these dumps. In fact its bed is made up of mine debris extracted during the mining activity and of waste materials of the washery activity. And the so-called Sea Drift opened onto the sea-side: a coastal outlet near Punta Argentiera at a height of about 10 meters above the sea surface. (source: Luciano Otelli - Argentiera: the field, the mine, the men)
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(source: www.comune.sassari.it)
CALA DELL’ARGENTIERA MAIN BEACH
Cinema Albergo operai scapoli Asilo
SMALLER BEACH
Chiesa S.Barbara BELVEDERE Scuola elementare
1 Laveria
Uffici amministrazione
PIAZZA M. CAMILLO
Dopolavoro minatori Villa Direttore
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
RECOVERY AREA AND SAFETY MEASURES: Comune di Sassari 1_THE MOUNTAIN SIDE AND THE SEA VIEWPOINT
DESCRIPTION: Steeply inclining slag heap, upon which was built the viewpoint area. The mountainside is inclined and rests upon a substrate of coastal rock outcroppings. There are clear signs of sea erosion at the base of the cliff. INVESTIGATION CARRIED OUT: Analyses on survey samples found traces of lead, cadmium and antimony. INTERVENTIONS: Saftey measures for the site through waterproof retaining structures of the old mining slag heaps with the use of concrete covering of the plaza, which is subsequently given a vegetation covering (trees, bushes, etc.) Also planned are the reshaping of the cliffs, as well as the re-routing of the sea swells with a breaking wall.
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picture by Gianni Alvito_Landscape and mines of Sardinia from above
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
THE SMALL CHURCH AND THE VIEW OF THE VILLAGE The church in Argentiera has not always been the one that we now see today. The original one was in the upper part of Calaunano, which was once the town where the miners lived, whereas the second was in a plaza but was a temporary wood structure, for use until the final and definitive church was built on a hill overlooking the entire bay. The church is called “Santa Barbara,” protector of miners, which, located as it was on the top of a hill, offers a wonderful of the entire town. The Camillo Marchese plaza (historical director of the mine) was the meeting point for the whole mine. There could be found administrative offices, the post office, the barracks of the finance police and, after a small widening, the after-hours area for workers. It was also where the coach stopped. Going down the only road leading in the direction of the plaza there was the elementary school, the only one serving the mine. In a position off to the side on the high part of via La Plata can be seen what was once the hotel for bachelor miners. The road bends near the clerks’ club, from which, as one descends towards the sea, can already be seen the outlines of the original mines of the late 1800s with the amazing washery made of “pitch pine” wood.
“La Cantina” was the only shop where it was possible to buy foodstuffs, fruit and vegetables and, as time went on, shops and clothing. On the hill overlooking the La Cantina ran a small road that was traversed by trucks on their way to unload slag into a hopper. After La Cantina, along the road could be found the “curve of the compressor”, which was used to send compressed air into the mine in order to ensure good air circulation for the workers (later the compressed air would be used also for automating the unloading of wagons full of minerals coming from the well). On the left, higher up, there was a plaza along which ran the rails for the transport of materials from the Podestà shaft to the Washery with a drawbridge, the carpenter’s and the mechanic’s, the butcher’s (who was the ice maker) and the green grocer’s. Beyond the washery it was possible to go to Bella Vista. There could be found the warehouse, the chemical lab and, just a little further on, the sea. In the widening in front of the warehouse were located two silos in which the mineral was stored before being loaded onto train cars, which were then pushed all the way to the docks. (source: La mia Argentiera - www.argentiera.castelmeteo.it / www.sardegnadigitallibrary.it)
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(source: www.comune.sassari.it)
CALA DELL’ARGENTIERA MAIN BEACH
Cinema Albergo operai scapoli Asilo
SMALLER BEACH
Chiesa S.Barbara 1 BELVEDERE Scuola elementare Laveria
Uffici amministrazione
PIAZZA M. CAMILLO
Dopolavoro minatori Villa Direttore
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
RECOVERY AREA AND SAFETY MEASURES: Comune di Sassari 1_CHURCH AREA
DESCRIPTION: Contained sloping slag heap which was the used as a gravel foundation of the church. The slag heaps below the church are in some points sharply inclined. The supporting structure at the foot of the cliff are in some points not suited to the task of retaining material that is washed away and carried onto the road by the elements. INVESTIGATION CARRIED OUT: Analyses carried out on survey samples have revealed traces of iron, lead, zinc, cadmium and antimony. INTERVENTIONS: Safety measures for the site through waterproof containment of the old mining slag heaps with limestone paving of the plaza surrounding the church and a vegetation covering on the surface including indigenous species on the slopes. Rerouting of waterways and reshaping of cliffs will be carried out.
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picture by Annacaterina Piras
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
THE OLD CALABRONIS MINE The mine is a complex industrial activity and its structure depends on various factors, but, essentially, upon the characteristics of the minerals to be extracted from the ore that contain them. Often the mine develops into more than one open quarry and underground shaft. The mine started out as an open quarry and expanded further into shafts that were dug into the mountain, which were started from the outside along the side of the mountain and reached the deposit therein. Once the deposit is reached, and fitted with transoms as required, mining may begin. Wherever the vein came to light, the shafts were dug along its grain, whereas others were pushed against the grain, actually cutting through them, and then cutting back along the grain in order to exploit it. The example of a classic transoming is the first leg of the Calabronis shaft, one of the oldest of the mine. These shafts, no higher than 2 meters, were developed horizontally with a slight slope toward the exit making it easier to drain away water and to transport hoppers full of material along rails out of the mine. To protect oneself from the dangers of the rocks, which at Argentiera were often unpredictable, the miner reinforced the shafts in order to avoid slides and collapses. To do this they used wooden beams against the
walls or pointed up at single blocks within the ceiling. With the horizontal excavation of shafts, furnaces, tunnels and development of the mining, the wood reinforcement technique was applied more intensely with the use of other supports, the so-called “quadri�. The stakes used in Argentiera were made up of pine trunks from Corsica with a diameter varying from 30 to 80 cm. The vertical shaft detaches at the various levels of depth, allowing the railways to transport hoppers full of material out of the mine. Here, the cars, pushed by the workers or pulled by mules, were sent to the plant or to the dump, if the extracted material was slag. The Carbonis area is in fact a large dumping ground. (source: Luciano Otelli - Argentiera: the field, the mine, the men)
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(source: www.comune.sassari.it)
CALABRONIS
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
RECOVERY AREA AND SAFETY MEASURES: Comune di Sassari 1_THE OLD CALABRONIS MINE
DESCRIPTION: The Calabronis dump is a heap of slag and discarded working material located near the “old mine”. The surface is vast, as is noted by the volume of heaped up material. INVESTIGATION CARRIED OUT: Analyses of survey samples have revealed traces of iron, lead, arsenic and mercury. INTERVENTIONS: Given the size of the site, the structural function of the support and the viability of a part of the heaps, we believe that the site must be rendered safe through phytoremediation, possibly even scaling up what has been planned for the pilot study at the Podestà shaft. This intervention will be complemented by water re-routing, reshaping and safety devices for the cliffs, aided by the creation of a waterproof paving.
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picture by Annacaterina Piras
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
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picture by Annacaterina Piras
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
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picture by Annacaterina Piras
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
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picture by Annacaterina Piras
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
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asparagus albus
centaurea horrida
euphorbia characias
asphodelus microcarpus
cistus incanus
euphorbia dendroides
astragalus terraccianoi
cistus salvifolius
euphorbia pithyusa
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Parco Geominerario, Storico e Ambientale della Sardegna + Parco Naturale Regionale di Porto Conte + Comune di Sassari | ARGENTIERA
ABACUS OF VEGETATION SPECIES
genista corsica
limonium acutifolium
rosmarinus officinalis
genista sardoa
lobularia maritima
stachys glutinosa
helichrysum microphyllum
quercus ilex
thymelaea tartonraira
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www.landworks.eu CONTACTS Scientific Director Prof. Stefan Tischer Tel. +39 328 368 2335 Email: stefan.tischer@gmail.com President of LandWorks Cultural Association + Scientific Coordination Annacaterina Piras Tel. +39 347 8054065 Email: apiras.landworks@gmail.com Vice President of LandWorks Cultural Association + Logystic Coordination Paola Serrittu Tel. +39 340 1400626 Email: paolaserrittu@gmail.com
For more information please contact: apiras.landworks@gmail.com
A
UNAM