technical documentation on the blasting technology used ... · documentatie tehnica privind...

DOCUMENTATIE TEHNICA PRIVIND TEHNOLOGIA DE IMPUSCARE IN APROPIEREA ZONELOR PROTEJATE DIN CADRUL PROIECTULUI MINIER - ROSIA MONTANA

S.C. IPROMIN S.A. BUCURESTI Pagina 1 din 64 IPROMIN S.A.

Technical Documentation on the blasting technology used within the close vicinity of the Protected Areas from Rosia Montana Project, Alba County

Table of contents Table of contents ..................................................................................................................... 1

Foreword ................................................................................................................................ 3

1. Background ......................................................................................................................... 3

1.1. The aim and scope of the documentation .................................................................................. 3

1.2. Perimeter Background Data ................................................................................................... 4

1.2.1. Administrative Location .............................................................................................. 4

1.2.2. Relief ......................................................................................................................... 5

1.2.3. Hydrography .............................................................................................................. 6

1.2.4. Underground Waters ................................................................................................... 9

1.2.5. Climate .................................................................................................................... 10

1.2.6. Flora ........................................................................................................................ 11

1.2.7. Fauna ....................................................................................................................... 12

1.2.7. Soils ........................................................................................................................ 14

1.3. Presentation of the heritage items from Rosia Montana, considered upon preparing the documentation ........................................................................................................................... 15

2. Deposit Geology ................................................................................................................ 25

2.1. Stratigraphic Data ............................................................................................................... 25

2.2. Rosia Montana Ore Deposit .................................................................................................. 29

2.3. Hydrogeology of the area and of the ore................................................................................. 30

2.4. Tectonics of the area and of the ore ....................................................................................... 30

3. Physical – mechanical characteristics of rocks ....................................................................... 31

4. Mining Method and Blasting Technology ............................................................................. 34

4.1. Ore deposit opening and preparation ..................................................................................... 37

4.2. Dislocation capacity ............................................................................................................ 39

4.3. Dislocation technology ......................................................................................................... 40

4.3.1. The geometrical parameters of the drilling works ......................................................... 40

4.3.2. The parameters for explosives loading and blasting procedures ...................................... 41

4.3.3. Blasting Network ...................................................................................................... 41

4.4. Estimated results of material dislocation by using explosives blasting ....................................... 42

4.4.1. Indicators ................................................................................................................. 42

4.4.2. The size of the material resulted after dislocation ......................................................... 42

4.4.3. Placement of the blasted material ............................................................................... 43

4.4.4. Projection of material ................................................................................................ 44

4.4.5. The seismic effect of blasting – the oscillation velocity of the material particle ................ 44

4.4.6. The volume of the gases and the overpressure within the air wave .................................. 47

4.5. The scope of dislocation technology that is using blasting with explosives boreholes ................... 47

5. The use of the blasting technologies near protected areas and historic monuments within Rosia Montana Mining Project ................................................................................................................................... 49

5.1. The basis of zoning the pits ................................................................................................... 49



5.2. The accepted level of the oscillation velocity of the material particle ......................................... 50

5.2.1. Characterization of area buildings ............................................................................... 50

5.3. Determining through calculation the blasting parameters within the restricted area with respect to explosives load depending on the oscillation velocity ..................................................................... 50

5.3.1. Size of explosive load ................................................................................................ 50

5.3.2. The technological options for dislocating material within the restricted area .................... 51

5.4. Details regarding the blasting technologies to be used within areas close to protected buildings (historic monuments) and areas ................................................................................................... 51

5.4.1. Mine adits technology ............................................................................................... 51

5.4.2. Boreholes technology, with borehole diameter of 125 mm ............................................. 52

5.4.3. The technologies and techniques used to blast the material within Rosia Montana Mining Perimeter for each of the protected areas .............................................................................. 56

6. Outlining the scopes of the blasting operations to be conducted for Rosia Montana Mining Project58

6.1. The principles of outlining the scope of blasting operations ...................................................... 58

6.2. Outlining the scope of blasting technologies ........................................................................... 59

7. The forecast on the effects generated by the blasting operations on the buildings and natural monuments located within the protected area ............................................................................................. 60

7.1. Monitoring the dynamic parameters ...................................................................................... 61

7.2. Monitoring objectives ........................................................................................................... 61

8. Conclusions and Proposals .................................................................................................. 61

Final Page ............................................................................................................................. 64

Drawings enclosed

1 Drawing presenting the location of the Mining-Development Perimeter within the region

2 Rosia Montana Mining-Development Perimeter Sheet 1:50.000

3 Status plan presenting the location of protected sites 1:5.000

4 Status plan presenting the seismic zoning and the standard quantities of

explosive 1:5.000

5 Section 1 – 1' 1:2.500/1:2.000

6 Section 2 – 2' 1:2.500/1:2.000

7 Section 3 – 3' 1:2.500/1:2.000

8 Section 4 – 4' 1:2.500/1:2.000




Foreword Rosia Montana Project has as a major element the adoption of most adequate measures for preserving an maintaining the integrity of the existing historic monuments and heritage houses, as well as of the protected areas. In order to quantify the effects of the blasting technology that is using explosives placed in a borehole on the buildings located within Rosia Montana Protected Area, a study on the blasting technology to be used within the pits has been prepared in 2006 with respect to its effects close to the building and historic monument. The respective study had three main parts:

1. Assessment of the technical status and the strength of the buildings; 2. “ in situ” measurements of the seismic oscillation generated at the level of the foundation of buildings

located within Rosia Montana Protected Area in case of a blasts produced at Cetate Pit; 3. The establishment of the blasting technology to be used in the pits, applicable within the areas

located close to the buildings from Rosia Montana, so as the seismic effect that is generated to be at a maximum velocity of 0.2 cm/s; at this velocity in accordance with the provisions under the DIN 4150/85 Norm (Germany), the effects on buildings are insignificant and cannot produce degradation or deterioration thereof.

Only the buildings located in Rosia Montana Protected Area have been considered in the previous study, the restrictive measures imposed for the blasting technologies to be used in the pits being aimed only to protect these buildings. Considering the fact that there are also other protected areas within Rosia Montana Mining Perimeter together with other buildings having historic monument value, outside Rosia Montana Protected Area, the blasting technologies and their areas of application that are not impacting the deterioration or damage of those buildings are presented in this study. The protected areas and buildings considered for this study are set forth below:

a) Piatra Corbului Protected Area; b) area between CP PUZ and Catalina-Monulesti Gallery; c) Carpeni Protected Area; d) Tau Gauri Protected Area; e) Orlea underground galleries; f) Greek Catholic Church and its Parish House; g) Simeon Balint’s grave; h) 4 monument houses located around current Mayoralty.

In order to develop the study, the results obtained from previous researches have been used. These researches were conducted on the effects of using the blasting technology for blasting the mining mass with explosives, i.e. “The study on the open pit mining technology within NAPOLEON and CORHURI Stockworks area and the effects of blastings on the neighboring area and buildings”, as well as the results obtained from field surveys conducted in early 2006. The seismic oscillation has been measured in 2006 during a blast in Cetate Pit, within the area of several buildings located within Rosia Montana Protected Area and on one of the monument buildings located near the current Mayoralty.

1. Background 1.1. The aim and scope of the documentation

The aim of this documentation is represented by the quantification of the effects of the excavation technologies to be performed within Rosia Montana Mining Perimeter and identification of technical and technological solutions that will ensure the protection of the Protected Area and of other historic monument buildings located outside the Rosia Montana Protected Area.



Roşia Montană

1.2. Perimeter Background Data 1.2.1. Administrative Location

From administrative point of view, the Mining-Development Perimeter where the mining activities are to be developed on the Rosia Montana Gold and Silver Deposit, Alba County is located within the following localities Rosia Montana commune and City of Abrud, Alba County, at approx. 80 km NW of the main city of the county, Alba Iulia.

Figure no. 1

Rosia Montana Commune is located at 7 km away from Alba Iulia-Abrud-Campeni-Turda Road and from the narrow gauge railway travelling from Turda to Abrud (decommissioned), and the access is made on County Road DJ 742. The closest regular railway is located at Zlatna, a town located on the railway traveling from Alba Iulia to Zlatna.



1.2.2. Relief Rosia Montana Mining Perimeter is found in the southern part of Apuseni Mountains, north of Meridional Carpathians and west of Transylvania Plateau. The site is hilly, with valleys alternating with elevated areas and includes known and partially mined gold and silver deposits within Orlea, Vaidoaia, Carnic, Carnicel, Cetate and Carpeni Mountains. Rosia Montana Site is located in the central western Romania within a region entitled Golden Quadrilateral, Apuseni Mountains, north of Deva and north-west of Alba Iulia, the main city of Alba County. From geo-morphological point of view, the region where the Rosia Montana Mining-Development Perimeter is located belongs to the structure of Southern Apuseni Mountains, Metaliferi Mountains group, located between Gaina Mountain and Drocea Mountain in the west and Vintului Mountains and Trascau Mountains in the east. The relief from the Rosia Montana Project impact area is typical for the mountain landscape from Metaliferi Mountains, having high and extended ridges, separating deep valleys, steep slopes and peaks rising above the ridges from the upper end of the valleys. The crests of the ridges are rounded by several rocky formations at the upper side of Rosia and Corna Valleys or on the crests neighboring the site and the slopes are usually steep. The relief is organized around Abrud Valley west of the Rosia Montana Project impact area, the Abrud Riber has the three valleys running from east as tributaries: Rosia, Seliste and Corna. The crests of these valleys and the eastern peaks are practically forming a natural caldron of volcanic origin around Rosia Montana, isolating it from eastern, northern and southern landscapes. The chain of the crests located west of Abrud Valley provides an even bigger isolation of the project impact area towards west. The relief units in the area are slopes, crests, valleys, and the highest percentage is held by lower and medium slopes.

Figure no. 2

Terrain configuration is frequently rough, and becomes hilly within valley areas with steep slopes. Friable, superficial and surface-rock skeleton soils (brown eu-mezobasic lithic, brown podzolic lithic) have occurred under these conditions of hilly terrain, being exposed to erosion.



The territory is located between 600 and 1300 m altitude. The following peaks occur on the northern and north-eastern limit: Zanoaga (1054.8m), Rotunda (1191m), Varsii Mari (1282.9m), Ghergheleu (1156m), and this is the boundary of the area on the N-NW side. The land slope is mostly steep (between 160 and 300) and very steep (between 310 and 400), but one can encounter slopes over 400. The general exposure of the territory, determined by the flowing direction of the main valley, is south-western and western. The hydrographic network is rich and contributed to the fragmentation of the land, determining a wide range of exposures, from sunny to shadowed areas or even over-shadowed areas on the northern slopes with steep slopes or valley bottoms. Abrud Depression comprises a hilly, tectonic, and erosion area. (Bucium, Abrud, Rosia Montana). Rosia Montana Depression is located along Rosia Valley as a prolonged couloir framed by a series of “hills” Rotunda, Cirnic, Dealul Cetatii, which are in fact ancient volcanic cones, and various non-ferrous ores are encountered inside them. It is worth noticing the anthropic micro-relief (galleries, mine entrances, waste dumps) that is proving the presence of ancient mining operations within this area of Apuseni Mountains. There are some geological formations with a special look, declared protected areas, as follows Piatra Despicata and Piatra Corbului. Along time, area relief underwent several changes, as a combined result of the action of natural and anthropic factors exerted during the last 2 millennia. Rosia Montana Perimeter is located south of Apuseni Mountains, north of Meridionali Carpathians and west of Transilvaniei Plateau. The site is hilly, with valleys alternating with high areas and includes gold and silver ore deposits known and partially mined in the Orlea, Vaidoaia, Cirnic, Cirnicel, Cetate and Carpeni. From geo-morphological point of view, the region of the Rosia Montana Perimeter belongs to the structure of Southern Apuseni Mountains, group of Metaliferi Mountains (V. Ivanov et all, 1976) located between Gaina Mountain and Drocea Mountain in their western side and Vintiului and Trascau Mountains in their eastern side. Rosia Montana region is characterized by a rather clearly distinguished relief, crossed by deep valleys. The region surrounding the pit sites is characterized by east to west ridges corresponding to the volcanic intrusions in a sequence of sedimentary rocks, resulting in a hilly terrain and relatively narrow valleys located between high ridges. The valley tops are ranging between 650 m and 1,085 m, the slope ridges being higher with 100 m up to 250 m. The water courses travel from the highest peaks, being concentrated east of the perimeter, down towards west and north, being tributaries of Abrud and Aries Rivers. Rosia Montana Perimeter is crossed by Rosia Creek travelling towards west, draining several linear ridges, east to west orientated. The south ridge is drained towards west and south-west by the adjacent valleys of Seliste and Corna. The north-east ridge is dominated by Rotund Hill (1091 m), which is the most western peak of the highest ridges located east of the site. Rosia Valley is surrounded by high areas with a mountainous look, having heights between 870 m and 1,070 m. The arrangement of Rosia Valley has been modified mostly due to mining activities, mainly in the western part of the perimeter, where a large surface has been impacted by the mining activities developed in the open pits and in the underground and by stockpiling waste rocks. The Mine Development Plan proposes that four large pits should be developed, pits located on Rosia Valley slopes, and to have depths comprised between 220 m/170 m and 260 m/ 420 m. The development of the pits is to be conducted both above the existent relief (slopes) as well as below it, following down the mineralization. The Tailings Management Facility (TMF) is located on Corna Valley, which is near Cetate and Cirnic Pits and Processing Plant sites, to be more specific the TMF is located south of these sites. Corna Valley has 5Km in length, with a level difference between its springs and its discharge point of approx. 400 m. Corna Valley waters are drained by Abrud River, the confluence being located 2Km upstream of the City of Abrud. Project development area is located within a mono-industrial area (mining), the existing infrastructure being rather good develop, especially electric power networks, roads and telecommunication networks. For the industrial water supply, one source may supply the need for the development of the project, and that source is Aries River, a river running in the close vicinity of the mine site.

1.2.3. Hydrography

General description of hydrographic basins



Aries River is the most important water resource from Apuseni Mountains, within Alba County territory. Three quarters of its drainage area and a total river length of 164Km are present within this area. Aries River runs approximately 10 Km north of Rosia Montana, collecting waters from several tributaries (for instance the water from Abrud River) and from several local valleys (for instance Stefancei Valley). Therefore, Aries River is a major river with considerable flow rate variations and the major potential source of raw water from the close vicinity of the proposed site of Rosia Montana Project. Abrud River springs from the close vicinity of Detunata ridge and it has a length of approx. 32.5 Km. The elevations of this river around Detunata Peak are of approx. 961 m and they go down to approx. 540 m at the discharge point into Aries River. The watercourses travel from the highest peaks, being concentrated east of the perimeter, down towards west and north, being tributaries of Abrud and Aries Rivers. Rosia Montana Perimeter is crossed by Rosia Creek travelling towards west, draining several linear ridges, east to west orientated. The south ridge is drained towards west and south-west by the adjacent valleys of Seliste and Corna. The riverbeds of these streams are not regulated, having their transversal cross-section under the shape of letter V, accentuated, with the bed consisting of alluvial deposits. The running and bayou waters, to include artificial lakes located within the Rosia Montana Project area are described below:

• The Rosia Creek springs from Taul Mare Lake, north east of Rosia Montana. Most of the existing mining activities are located within Rosia Creek drainage area. Four sampling points have been established on the course of Rosia Creek, both in areas impacted as well as in areas not impacted by mining: Rosia 1 – upstream of Rosia Montana, Rosia 2 – the entry point into the commune, Rosia 3 – in the middle of Rosia Montana, Rosia 4 – before the discharge point into Abrud River.

• Abrud River is receiving tributaries from Rosia Montana, Corna, Bucium, and Vartop Valleys. Abrud River flows north into Aries River at approx. 6 Km north of the confluence with Rosia Valley. A qualitative sampling point has been established on Abrud River, downstream of the confluence with Rosia Creek.

• Corna Valley is located south of Rosia Montana on the southern side of the current mine. Corna Creek flows south – south-west and enters Abrud River upstream of the City of Abrud. Two sampling points have been established on Corna Creek: one in Corna and the other one downstream of the village.

• Saliste Creek is a small water course running west of the current mine. The upper parts of the basin are relatively not impacted. A waste dump is located in the lower part of its basin, in the immediate upstream of the confluence with Abrud River. Samples of aquatic species have been collected from a point located upstream of the dump and the physical and chemical parameters have been measured in a downstream point.

• Vartop Valley is north of Rosia Valley and it is not impacted, except for the forestry related works conducted on some of its sections. Two sampling points have been selected to compare these data with the ones collected from impacted valleys. A sampling point has been placed in a coniferous forest and one in a beech forest.

• Aries River is the emissary of Abrud River, and all the waters from the valleys from which samples have been collected are discharging into this river. Aries Rivers runs towards east at approx. 6 Km north of Rosia Valley. Two sampling points have been established on Aries River, one upstream and one downstream of the confluence with Abrud River.

The following aquatic ecosystems have been identified through an analysis of the topographic survey drawings that may be present within the general assessment area:

• creeks; • lakes; • riparian wet zones; • non riparian wet zones.

Most of the riparian wet zones have been limited to the creek and lake ecotone. A riparian wet zone from Saliste Valley (upstream of the current TMF) is the result of a small dam built in the past.

Surface waters flow



Hydrologic data for Aries River (at Campeni). These data have been secured from the hydrological stations of INMH from Abrud and Campeni. As a percentage from the Aries flow rate at Campeni, the flow rates are as follows: Abrud (11.4%), Rosia (1.4%), Seliste (0.9%), Corna (1.1%) and Abruzel (1.1%). Stefancei Valley covers an area of 1,128 ha and flows towards north. The creek flows directly into Aries River, way downstream of the other valleys. There are two TMFs present on these valleys, operated by Rosia Poieni Mine. Due to the fact that there is no plan for including the valley in the proposed mining area, no data have been collected from the sampling points established on this valley. A weir was placed on this valley, but it was abandoned. The weir was designed in such a manner that it doesn’t meet the small flow rate measurements. The waters draining from underground mining works contribute to the surface water flow rates present in Abruzel, Rosia and Corna Valleys. The largest quantities of acid waters drained from underground mines are recorded in Rosia Montana. The drainages from two major galleries contribute to the flow rate increase of Rosia Creek, the most significant contribution is brought by the gallery from 714 m dnMN Gallery (R085 monitoring point or Gallery no. 714). Recent observations conducted for the drainages resulted from Gallery 714 released in Rosia Valley show that the average flow rate varies on a monthly basis from approx. 39.6 to 63.0 m3/h (11.0 – 17.5 l/s). Based on these elements, the estimated average flow rate is of 51.1 m3/h (14.2 l/s). Approx. 8 % from the average flow rate of Rosia Valley results from Gallery 714. Corna Valley also collects significant mine waters release (16.2 m3/h, 4.5 l/s) from two sources close to one another, which seem to be springs. Due to the rusty look of the water, the low values of the pH and their proximity to existing mining works, it is assumed that these courses result from collapsed mining galleries. The drainage from Seliste Valley that is significantly higher may be caused by the drainages resulted from the TMFs of the current mine that is operated by ROSIAMIN. The synthetic presentation of flow rates demonstrates the rapid reaction of surface runoffs to precipitations. The clay shales that dominate the geology on a significant area of Project site have as a result a low permeability of soils, reducing infiltration of precipitations. The volcanic rocks from Project area also present a low permeability. Therefore, a large portion of storm waters resulted from heavy precipitations are reflected in the surface runoffs. The lack of large lakes in these valleys limits the retaining capacity of floods into the basin. The immediate reaction to precipitation was also noticed in the mine drainages, suggesting the presence of some direct infiltrations for the precipitation waters, both inside and outside the area of underground workings network. Lakes The local lakes (tauri) have been mainly built during the XIXth Century so as to be used as retaining basins for the water used to extract gold and are usually placed in higher grounds The largest lakes are:

• Taul Mare Lake, close to the springs of Rosia (Area = 32,120 m2, Volume = 160,600, m3, Maximum Depth = 10 m;

• Tarina Lake, on the north side of the upper Rosia Valley (Area = 10,480 m2, Volume = 27,300 m3, Maximum Depth = 4.5 m);

• Brazilor Lake, on the south side of the upper Rosia Valley (Area = 7,800 m2, Volume = 22,000 m3, Maximum Depth = 5.5 m);

• Anghel Lake, on the south side of the upper Rosia Valley (Area = 4,250 m2, Volume = 8,500 m3, Maximum Depth = 4.5 m);

• Corna Lake, at the springs of Corna (Area = 8,830 m2, Volume = 15,930 m3, Maximum Depth = 3.6 m).

It seems that these artificial lakes are supplied with water resulted from local springs. No flow releases have been observed and there is no significant water consumption. That is why, they do not play a significant role in the hydrology of the area and it is assumed that the water intake from the supply springs is compensated by the evaporation and seepage. That lake water is generally speaking of good quality, not exceeding the current standards, except for mercury and selenium. Significant quantities of mercury have been discovered in the water, exceeding 10 times the standard value. Mercury was not usually detected in other waters associated with the Project area, not even in the mine waters, but mercury was commonly used during historic processing of gold and it is possible for mercury to occur from those activities because these lakes have been used during the XIXth Century to extract gold.



Initially, the surface waters present in local valleys, to include the entire course followed by Abrud River, are characterized as being polluted due to the fact that these waters cannot sustain fish life. To conclude, one can say that the area surface waters are significantly degraded due to the historic and current mining practices. The most significant result is the accumulation of potentially toxic heavy metals in the environment.

1.2.4. Underground Waters

The potentially water bearing rocks existing within Project site are Jurassic and Cretaceous sedimentary rocks, the volcanic layers and the alluviums and colluviums superficial deposits. The Jurassic and Cretaceous sedimentary rocks present within Project site consist also from discontinuous layers of sandstones and conglomerates that do not supply significant water quantities. Most of the Cretaceous sediments, to include thick marl shale have a very low permeability. The volcanic dacite, the vent breccias, and the black breccias have also a low primary permeability. The permeability that still exists in the sedimentary and volcanic sequences is due to the secondary structural characteristics, like fractures and faults. The superficial unconsolidated deposits and the weathered rocks located close to the surface may have a significant capacity of retaining water for some of their sections, but there are too thin to be used as large or medium water supply sources and are more suitable as small water supplies, which may be used for domestic purposes. The andesites flows from late post-mineralization stage from Neogene and the pyroclasts, dominated by the agglomerates occur immediately north of Jig and east of Cirnic, as well as under the shape of residual debris in Orlea, north of Rosia Valley. These andesitic volcanic units are weakly porous and allow a certain circulation of underground waters through the agglomerated units and at the contact areas with the rock generally impermeable by underlying Cretaceous sediments. Within these contact areas several springs and small lakes occur, at large distances from the project site. Details regarding these three potentially water bearing units existing within the site (sedimentary rocks, volcanic rocks and superficial deposits) are presented below. Sedimentary Rocks The sedimentary rocks from late Jurassic – Cretaceous consist especially from flysch deposits of black shales of low permeability (below 1 × 10-5 cm/s, approx. 1 × 10-2 m/day – one should note that it is not about velocity, although it is measured in the same sizes/units). The younger layers from Abruzel unit belong to the Maastrichtian age and consist of sandstone layer intercalations, conglomerates and marl shales (called micaceous coarse flysch and coarse sandstone on local geological maps). Several layers of intercalated sandstones and clay shales have been encountered by the monitoring hydro-geological drillings conducted on Seliste Valley. The thickness of the sandstone and conglomerate layers varies from some millimeters to approx. one meter. The fact that the geology is deeply disturbed means that these layers are discontinuous and encapsulated in low permeability shales. Therefore, these layers do not have a significant water bearing capacity and their investigation is useless. Their water bearing capacity is still mostly a secondary one, due to the structural deformation and the presence of brecciated rocks in the areas associated with the shearing areas. Also, it was noted that the base rock present in the vicinity of the surface has a relatively high permeability than the deeper layers. This permeability is associated with the weathered rock level. The circulation of underground water mostly occurs in the weathered level existing in the close vicinity of the contact area with the colluviums layer and with the soil. Volcanic Rocks The volcanic units are extremely heterogeneous and anisotropic, and consequently the hydro-geological properties vary significantly on small distances. It is possible for the primary permeability to contribute in a small proportion to the water bearing capacity from this unit. Where significant water quantities occur, they are especially caused by the secondary permeability. It is also possible that within the mining areas, the mine waters would dissolve more and would increase subsequently the permeability of calcareous areas present inside breccias. Calcite may be found in the surrounding sedimentary rocks, constituting the vent breccias together with the Neogene volcanic rocks. But, otherwise, in other areas a low permeability of this unit has been proved. The hydro-geological drilling conducted in the upper side of Abruzel Valley identified vent breccias at depths of 10-14 m. These breccias occur as impermeable base supporting an aquifer hosted in the overhead colluvium layer. The encountered dacites have a low permeability. The primary permeability is insignificant and there are few evidences of natural secondary permeability. The hydro-geological assessment drillings of the vent breccias have been conducted in the upper Rosia Valley. The small quantities of underground water encountered by these drillings were found in thin layers close to the surface.



The hyrdogeological deep drilling conducted in Rosia Valley identified dacites from the surface down to a 220 m depth. The base of the drill was located at 570 m dnMN level. No significant layers of water have been encountered, although the observation drillings conducted in the mine galleries indicate the presence of water at over 700 m dnMN level. No water was found in the pumping test conducted in the dacites present in gallery located at 714 m dnMN level (also known as Gallery 714). These acknowledgements indicate the lack of a continuous phreatic surface (underground water level) at approx. 700 m dnMN in the volcanic sequences; the natural layers and pipes capable of transporting underground waters are rather limited. The andesite flows from late post-mineralization stage from Neogene and the agglomerates from Rosia Poieni and the andesites from Rotunda occur on the upper course of Corna and Rosia, especially over Cretaceous sedimentary units, with small overtops on the vent breccia units. The agglomerates present some weak porosity, but generally speaking are thin layers, away from the project area and over impermeable Cretaceous sedimentary units, as described above. Superficial Deposits Superficial deposits consist of colluviums, alluviums, and artificial deposits – backfill and mine wastes. It results from the samples collected that these deposits do not have generally speaking a higher thickness than 10 m. They may have a significant water bearing capacity, but the reduced saturated thickness signifies the fact that these are not significant water resources. These supply several domestic wells, which have been dug manually throughout the entire area. The colluviums are generally widely disseminated, except for the rocky outcrops area or the ones where alluviums are the predominant surface material (e.g. on the bottom of valleys/creeks). The colluviums observed on the site are a mixture of soil and rocks deposited through the action of water and/or massive landslides on the slopes and base rock debris (the full weathered base rock as soil or as clayish material, respectively). The colluviums have a reduced water bearing capacity, presenting an estimated hydraulic conductivity (permeability) of 1 × 10-6 cm/s (approx. 1 × 10-3 m/day). That is why, the colluviums are generally a barrier against underground water circulation. This property is to be used upon building the TMF and during construction stage, when all rocks or alluviums present within the TMF perimeter are to be harmonized and covered with a layer of compacted colluviums. The alluviums occur along valleys bottom, on the section covered by the current creek beds. These surface alluviums deposits present in the creek beds are reaching depths of 12 meters and may function as a local aquifer. The average hydraulic conductivity is relatively high, between 2 x 10-4 to 3 x 10-2 cm/s (0.2 to 26 m/day).

1.2.5. Climate

The region climate is classified as being a temperate continental climate with topographic influences. The annual average temperature is of 5.4° C, with maximum and minimum temperatures of the monthly average temperatures of 24.7° C (summer) and -8.2° C (winter), respectively. The relative humidity of air is approx. 77% throughout the entire period, with the highest values recorded in September 1996 (92%) and December 1988 (93%). The lowest relative humidity of air was recorded in May 2001 (70%). The distribution of total nebulosity shows a direct correlation with air humidity. The average multi-annual wind directions indicated the dominant direction as being south – east (frequency of 30.2%), followed by the north – east and west directions. The south-west – north-east direction of Rosia Valley has a major role in creating the main wind direction. The average wind speed on each direction presents values between 1.4 and 4.8 m/s.

Air Temperature The average multiannual value of air is 5.5 °C. The maximum values of the multiannual average of maximum air temperatures have been recorded in July and August (19.8 °C and 20.1 °C), and the minimum values in December and January (0.3 °C and 0.6 °C). The annual average values of the maximum temperatures that have exceeded 10 °C have been recorded in 1990, 2000, 2002 and 2003. The lowest multiannual values of minimum average temperatures have been recorded between December and February (between -5.7 °C and -5.3 °C), and the highest values in July and August (12.1°C and 12.5 °C). The annual average values of the minimum average temperature have been positive, being between 2.1 and 4.0 °C. The maximum absolute temperature recorded during the analyzed period has been comprised between 11.4 °C (07.01.2001) and 29.8 °C (22.08.2000).

The minimum absolute temperature recorded during the analyzed period has been between – 21.9 °C (13.02.2004) and 4.6 °C (29.08.1998). Relative Air Humidity



The average relative air humidity is approx. 76.2 % for the entire period, the most humid periods being recorded in January (81.1%) and in February (80.7%). The relative air humidity exceeded 70 % for the entire analyzed period, both as multiannual monthly average and as annual average (except for 1992 and 2000). These values allow the classification of the area as an area with a high humidity of air. Cloudiness (the state of the sky when it is covered by clouds) The multiannual monthly averages of the cloudiness indicate the November-May period as the one with the highest degree of clouds coverage (6.0 – 6.5 tens). The multiannual average cloudiness during the analyzed period has been 5.8 tens. The lowest value (4.5 tens) of the multiannual monthly average has been recorded in August. Precipitations and Snow Layer The precipitations are usually present as rainfalls most of the year; snow is falling only during several winter months. Peak precipitations occur usually during summer, the highest values of the monthly averages being recorded in June or in July. The highest values of the monthly averages have been recorded at Rotunda and Abrud, and they were 91.8 mm (July) and 106.4 mm (June). The maximum monthly values of precipitations at the three weather stations during recording period have been 230.9 mm (July 2005) at Rotunda, 168.1 mm (July 2005) at Project Weather Station and of 232.4 mm (December 1981) at Abrud. These data are demonstrating the spatial variability on distances close to the precipitation phenomena and the fact that extreme precipitations may occur both during summer and during winter. The difference between Project Weather Station in Rosia Montana and the one belonging to INMH at Rotunda is especially related to their altitudes (the latter one is located at a higher altitude, over 300 m difference). A large part of the winter precipitations consists of snow and they have been recorded to occur from October until March. Usually, snow remains on the soil from December until March; the most significant defrosts occur usually in March. In extreme situations, snow may fall even from September and remains on the soil until May. Wind The typical parameters for the wind are measured at 10m above the ground. In order to characterize wind, the following parameters are used in this paper: multiannual average frequency on 8 directions (%) and monthly averages of wind speed on directions (m/s). For the analyzed period, the multiannual average frequencies of wind directions indicate the fact that the main direction is South West (frequency of 30.3 %), followed by the North East direction (frequency of 13.5 %) and West direction (frequency 8.4 %). The main direction of the wind (South West) occurs mostly between September and March (31.5 – 38.4 %), to include transition seasons and winter. The second direction (North East) occurs mostly during hot season. The multiannual average value of the frequency of the air calmness is of 17.7 %, having maximum values (of over 20%) recorded in January, June, and August. The average wind speed has been recorded to be between 2.0 and 4.1 m/s during the analyzed period. The highest values have been recorded on the main direction (South West) and on the West direction. Sunlight The lowest average values of the sunlight have been recorded between November and January (28.37-58.23 hrs/month). The most elevated values have been recorded between May and August (197.13-233.34 hrs/month). The total sunlight varied between 1447.33 and 1830.85 hrs, with a multiannual average of 1596.07 hrs. Because of these values the area is framed in the category of areas with relatively reduced sunlight periods.

1.2.6. Flora

It is obvious that two existent vegetal formations are well differentiated: nemoral formation, and the eremial ones, that from phytocenologic point of view belong to three major vegetation levels: The sub-level with the largest dissemination (over 60%) is the beech forests and mixture forests, followed by the sub-level of the spruce forests (over 35%). Vegetation that belongs to the sub-alpine sub-level has been established on a smaller scale around the highest peaks, within isolated areas, not exceeding 5% of the total area. Pursuant to the previous botanic studies [St. Csuros, 1972], the primary vegetation of Aries basin, along its water course, was dominated by hygrophile wood species, grouped in specific associations, as follows: Salicetum purpurae, or Salicetum triandrae which depending on the plain dimension, were covering larger or smaller areas.



The species found in these plain woods were: Salix alba, S. fragilis, Populus alba, P. nigra, P. tremula, Alnus glutinosa, A. incana. The grass vegetation (the alliances Nanocyperion and Polygono-chenopodion) are developing within gravel, sand or mud sand areas, reaching the daylight only during low water levels (July – September). Associations dominated by reed (Scirpo-Phragmitetum), occurred in favorable areas, especially on the course of lower Aries, together with or neighbored by hygrophile bushwood. In the place of plain wood, secondary grass associations developed, which characteristically have the following species of plants Carex (C. acutiformis, C. riparia, C. gracilis, C. inflata etc.) and cereal crops (Molinia coerulea, Deschampsia cespitosa, Poa trivialis, Agrostis alba, A. tenuis, Alopecurus pratensis, Festuca pratensis, F. rubra, Poa pratensis, Trisetum flavescens, Agropyrum repens, Arrhenaterum elatius etc.).

Local Context The Project perimeter is found in an area with no major biodiversity interest. This is due to the multiple interactions and on long term due to the interactions between environmental and anthropic factors. If for Romania the factors impacting the biodiversity were focused mainly on the agricultural activities, the industrial impact was felt only in the second half of the XXth Century. The biodiversity impact was caused by the industrial activity previously developed in Rosia Montana. It is noticeable the bivalence of this impact generating couple. The presence of gold and silver ores within Rosia Montana area made this area a much inhabited one, with unusual densities for this altitude. A significant increase of population density is noticeable within Aries Valley area, to include Rosia Montana. The industrial importance of the area attracted the need for developing a special industrial infrastructure, starting with ensuring the needs for the daily living and until the adjacent domains that are supporting the ore deposit development activity, emphasizing the forestry developments that have provided the necessary materials (support beams, traditional mining installations, fire wood, etc.). Thus, we would like to underline the cuttings performed for several valuable species like oak Quercus robur (increase strength to the mines), beech Fagus sylvatica (providing fire wood at a high heating effect), as well as some coniferous species especially fir Abies alba but also spruce Picea abies (that have ensure the necessary construction timber both at the surface and in the underground, both industrial as well as for support, agricultural and transport business, etc.). It was noticed an invasive process of the forestry areas of pioneer species of low importance like birch (Betula pendula) or hazel (Corylus avellana). Following the unprecedented development of industrial fields, one can say without any prejudice that this area is one of the most impacted areas of Romania, the biodiversity being strongly impacted. Due to the anthropic activities related to the natural resources development, even from ancient times, it is extremely difficult to identify areas where a certain natural integrity was maintained, where functional natural balances would exist.

1.2.7. Fauna

The insects identified on the site of the future investment occur in almost all types of habitat. The large number of species and individuals as well as the extraordinary diversity of these species constitutes the element that provides a special relevance in most of the food chains present on Terra. The role of the insects in the energy related cycles from different ecosystems results in two major situations: consumers (predators) and food (prey). From insects, the Carabidae Coleoptera are very common (C. sycophanta L. and C. inquisitor L.) destroying caterpillars and pupals of the main defoliators of the woods. The Coccinelidae Family has numerous representatives that are feeding themselves with green fly, soft brown scale and phytophagy acarian (of the following genus Coccinella, Pullus, Exochomus, Stethorus, etc.). A critical role in limiting the population of pests is played by the wood ants (Formica rufa L.), contributing largely to the maintenance of the biocenotic balance within forests. Large colonies of ants attract useful birds for which they become food. Diptera order is represented by Cecidomyiidae (Aphidoletes sp. ), Syrphidae (Syrphus sp.) and Chamaemyidae (Leucopis sp.) families. Aside several species of Cecidomyiidae pests for green flies and Psilidae (Endaphis sp.) and Bombiliidae pests for worms (Villa sp.), the dipteral order is represented by two large families – Tachinidae and Sarcophagidae. Tachinidae Family comprises medium-large size flies that are either laying eggs directly on or inside their host or on leaves that are subsequently consumed by pests. In the first case the fecundity is average and affects a large



number of defoliating pests, Parasetigena silvestris R.D., Exorista larvarum and Bessa fugax Rond, being the relevant examples in this case. Compsilura coccinata Meig. is introducing the eggs in the host’s body parasitoiding in this manner 150 species of defoliators. The pests that lay eggs on a sublayer are characterised by a high fecundity (up to 4000 eggs for the parasite Microphthalma europaea Egg. on bug larvae). Several species are known from the Sarcophagidae Family, of the Sarcophaga (S. uliginosa Kram., S. albiceps Meig. genus, etc.) that are developing inside worms and pupals of defoliators. Parasite Hymenoptera belong to parasitica suborder, and a critical role in regulating the number of pest populations is played by the representatives of Paraconidae, Ichneumonidae, Pteromalidae, Encyrtidae and Trichogramidae Families. Braconidae Family comprises small and medium insects of different colours. Mostly they are endoparasites and impact pests at different development stages (adults of coleoptera and hemiptera and worms or eggs of defoliators). As ectoparasites they are developing on hosts that live a hidden life within galleries or twisted leaves. Ichneumonidae Family is spread especially within wet climate areas, because the presence of water is a critical factor in the life of adults. Most of these parasites of the wood pests belong to the Ephialtinae subfamily that comprises the endoparasites of Lepidoptera pupals, the ectoparasites of Coleoptera, Lepidoptera and Hymenoptera larvae that are developing in wood, twisted leaves and fruits. Pteromalus puparum L., a parasite belongs to the Pteromalidae Family and is developing in the pupals of some Lepidoptera and an ectoparasite named Eupteromalus nidulans (Thorus.) of the young worms of defoliators. Encyrtidae Family comprises egg parasites, parasites of most Lepidoptera, Ooencyrtus genus being dominant (O. tardus Ratz.. O. concinus Rom., O. neustriae Merc., O. kuwanai How.). Numerous species of this Family are parasites of coccids and green flies. Trichogramidae Family comprises very small insects (under 1 mm) a parasite of the eggs of numerous pest species (Trichogramma evanescens Westw., T. embryophagum Htg., T. semblidis Aur.). Bentos Fauna A special category of aquatic invertebrates is represented by the bentos fauna. Bentos invertebrates’ communities are highly sensitive to stress. The typical features are a useful tool to detect stress on the environment following the action of diffuse point pollution sources. Due to their poor mobility and their extended life cycles (one year or more), their features are dependent on the conditions of the immediate past. The reactions against pollutants rarely release, which may be difficult to detect through periodic collection of chemical samples is one of these features. Vertebrates Fish The entire study area is located within the territory of Abrud Valley Fishery. There is no fish in the streams of this Fishery in accordance with the data comprised in the development of Cimpeni Forestry Authority (ICAS Database,Developments 1977-1998). Several attempts were made to repopulate the waters with chub and barbell but the results were unsatisfactory due to their pollution with residual waters of the mining operations. To conclude, one cannot speak about the presence of fish populations within running waters present within the Rosia Montana Mining Project Perimeter, due to the following reasons:

- physical and chemical parameters of most of the running waters (including Abrud River that is collecting waters in the studied area) determine an unsuitable quality of waters for supporting viable fish populations;

- where the water quality is not an impediment, the water courses have a limited food supply and a poor flow that do not support fish.

The presence of several fish species of Cyprinidae Family (common carp, fry, gudgeon, carassius, loach) and Esocidae Family (pike) have been reported in several local lakes, among which we can specify Anghel, Brazilor and Corna. These are of course species introduced in time in these artificial lakes. In accordance with the data secured after conducting hydro-biological analyses, the water quality of these waters is depreciated. One of the causes of this phenomenon is represented by the technological process used by the mining operations that were poorly engineered in the past when the long term environmental protection was not an objective of mankind. Amphibians. The presence of amphibian species has been recorded during birds count. Reptiles. Four species of reptiles have been identified within studied area.



Birds. Eighty three species of birds have been recorded within project area. Considering the study period, one may assume the fact that most of these species are nesting in the area. Approx. 45% of the recorded birds that nest within project area are migrating birds. The remaining 55% are resident birds. Approx. 77% of the recorded nesting birds are forest birds. Approx. 9% of the species are found in one of the following habitats: meadows and pastures, forest edges and small forestry clusters and in localities. Only approx. 4% of the birds are associated with wet lands. The usual size of the territory during reproductive season for the recorded species vary from 0.3 ha (Winter Wren Troglodytes troglodytes) to over 180 ha (Common Buzzard Buteo buteo). There are eight species of top predators, both diurnal (Goshawk Accipiter gentilis, Eurasian Sparrowhawk Accipiter nisis, Common Buzzard Buteo buteo and Common Kestrel Falco tinnunculus) and nocturnal (Eurasian Scops-owl Otus scops, Little Owl Athene noctua, Tawny Owl Strix aluco, Long-eared Owl Asio otus). Predators are very sensitive to perturbation, especially within their nesting territories. Other sensitive species with respect to their territory recorded within project area are several species of woodpeckers (White-backed Woodpecker Dendrocopos leucotos, Middle Spotted Woodpecker Dendrocopos medius, Black Woodpecker Dryocopus martius, Grey-headed Woodpecker Picus canus and Green Woodpecker Picus viridis), who need a habitat consisting of large blocks of wood exceeding 10 ha. Mammals. Thirty one species of mammals have been recorded within project area. Among top predators one can find here the weasel, the ferret, the martens and the stone martens. No large resident carnivores have been recorded. Wolf footprints have been rarely recorded crossing the territory under study. Other mammals: European Badger (Meles meles), Red Fox (Vulpes vulpes), European Hare (Lepus europeus), Wild Boar (Sus scrofa), European Roe Deer (Capreolus capreolus).

1.2.7. Soils

Types and sub-types of soils Brown eu soils – typical mesobasic ( Eutric Cambisols) These soils are found especially within Corna Valley Basin, on the interfluvium between Corna and Rosia Valleys, on a poor – moderate hilly relief (600 – 800 m altitude), short or long, uniform or non-uniform, with moderate angles slopes (slopes of 12 – 25%). These soils have been divided on the map as monotype units but also as associations with brown eu soils – lithic mesobasic, typical acid brown soils or typical regosoils. They formed on parental materials resulted from clays or clayish flysch with silty sequences. Brown eu soils – lithic mesobasic (Lepti eutric Cambisols) These are soils typical for several relief forms with short, non-uniform from mofderate to steep slopes (10.1 – 50%) or some narrow valleys with no meadows (Corna, Rosia with some of their tributaries). They occur in association with brow eu soils – typical mesobasic, lithic brown acidic soils and typical lithosoils at local level and as monotype units. They mainly formed on clayish flisch with silty or andesitic intrusions. Brown eu soils – andic mesobasic (Andi eutric Cambisols) and Brown eu soils – lithic andic mesobasic (Andi lepti eutric Cambisols) They are spread in areas with volcanic sedimentary formations where andesite are significantly disseminated, determining their andic feature. Relief is varied, in general with large ridges (30 – 100 m width) ore weak to high slopes (2.1 – 50%). Brown eu soils – andic mesobasic occur often with two associated subtypes (andic – lithic), locally they have been separated in associations with typical lithosoils. The parental material, of medium-medium fine texture, having skeleton is resulted from andesites weathering process. Typical acid brown soils (Dystric Cambisol) and lithic acid brown soils (Lepti–dystric Cambisols) These have the largest dissemination within the territory, usually being encountered at high altitudes of 700 – 800 m, within Corna and Rosia basins, on a moderated hilly relief with mainly narrow ridges (< 30 m width) and uniform – non-uniform short slopes; locally they occur on narrow valleys with no meadows. They have been separated on the map as monotype units, but most frequently in association with lithic acidic brown soils, brown eu soils – typical or lithic mesobasic, typical lithosoils and regosoils.



The parental material consists of alluvium and delluvium blanket deposits, having medium – coarse texture and a skeleton resulted from the weathering of the silty flisch. Andic acidic brown soils (Andic dystric Cambisols) and lithic acidic brown soils (Andi–lepti–dystric Cambisols) These are soils found in close connection with the paternal deposits resulted from the weathering process of the intermediary eruptive rocks, andesitic predominant, belonging to the volcanic sedimentary formations. They occur around the volcanic mountains Cetate and Cirnic, on large ridges and non-uniform, short or long, low to high slopes (2.1 – 50%). Therefore, soils have been separated on the map in monotype units (pure) or in associations with typical lithosoils and regosoils; locally on small surfaces, the andic brown soils are associated with cambic andosoils (soils of Au (Aou) – AB – Bv – CR – R type, dark greyish brown coloured, formed on andesites). Typical regosoils (Eutric Regosols) and lithic regosoils (Leptic Regosols) These are mineral soils, poorly developed on unconsolidated parental materials, with a medium – coarse texture, having a skeleton of different origins: clays, silty flisch, clay marls or andesitic detritus. These occur on small areas mainly as meosbasic eu brown soils, typical acid brown soils, andic acidic brown soils, typical lythosoils, as monotypic units (pure). They are spread on uneaven, long or short, medium to strongly inclined slopes (12-50%). Typical coluvium soils (Fluvisols) Like the regosoils, these are soils poorly developed formed on unconsolidated parental materials with medium – medium fine texture, resulted from weathering clays and clayish materials with skeleton. They occur on small surfaces located in the north – eastern side of the territory at the base of several non-uniform, short, with a medium angle slopes (10 – 40%) that are surrounding some of the artificial lakes in the area. Typical lithosoils (Eutri lithic Leptosols) These are found on narrow ridges, non-uniform, short or long, low to high angle slopes (10 – 90%). They occur as the second term in association with andic brown souls, typical acid brown soils, lithic, andic, lithic regosiols and rocky areas (exposed rock). Different deposits have been formed: andesitic detritus, silty flisch and even waste possessing different textural, physical and chemical features.

The works shall be developed within the north western area of Alba County, and the site presents the following characteristics:

– SEISM – in accordance with P100-2006: - Seismic area of calculation VI MKS (ag = 0.08 g), - Corner period Tc = 0.7 s;

– SNOW – in accordance with Designing Code CR - 1 - 1 - 3 - 2005: - Sok = 1.5 KN/m2, - Exposure coefficient ce = 0.9, - Snow agglomeration coefficient � = 0.9, - Frost depth = 90 cm;

– WIND – in accordance with Code NP-082-04: - Reference pressure qref >0.4 kPa, - Reference velocity Vref = 31 m/s.

1.3. Presentation of the heritage items from Rosia Montana, considered upon preparing the

documentation The archaeological vestiges of the ancient Alburnus Maior, Rosia Montana today, have brought the international reputation to this site, and transforming this site in a reference marker within European and World Cultural Heritage. Together with the valuable archaeological heritage, the historic monuments from Rosia Montana, the vernacular architecture marked by sensitive features of the local spirit and the industrial landscape of traditional gold mining make this settlement to be the mirror of a particular cohabitation type between different communities that have marked the historical environment.



The sites that are relevant from the seismic protection point of view are set forth below: � Piatra Corbului Protected Area (surface and underground), � PUZ CP area and Catalina-Monulesti, � Carpeni Protected Area (surface and underground), � Tau Gauri Protected Area (surface), � Orlea underground galleries, � Greek Catholic Church and its Parish House, � Simeon Balint’s grave, � four monument houses located around current Mayoralty.

Figure no. 3



Piatra Corbului. surface – natural monument Catalina-Monulesti Roman Gallery – Historic Monument



Carpeni. surface – historic monument Carpeni. underground – historic monument



Taul Gauri. surface – Roman circular monument Greek Catholic Church (1841-1847) Corna no. 692

The church is representative for the traditional cult architecture of the area. Its dimensions that are smaller than the other cult edifices existing in the area are compensated by the observance of the particular features of the site, ensuring the high ascendant perception on the monument. The Greek-Catholic Church has a particular significance, being related to the Simeon Balint, a priest that was a prefect of Avram Iancu during 1848 Revolution. Simeon Balint is buried in the church cemetery. Historic markers:

1741 – construction of the church, 1772 – is embracing the Greek-Catholic Cult during the times of priest Petru Dib, 1750-1800 – the southern façade portico is built (Simeon Balint, 1818-1880, Greek-Catholic protopope at

Rosia Montana, a former tribune of Avram Iancu and prefect during 1848 Revolution),



1948 – the church returns to Orthodoxy. Today – Greek-Catholic Church: – a church with a half-circular falling out apse on its eastern side and bell tower on its western side; – a square pavilion was built later near the access on the southern side of the nave; – a rectangular nave consisting of 3 spans covered by a vella archways placed on double arches,

discharging on support pillars with a retreat and profiled cornice; – the apse is covered by a half-calotte; wall iconostasis with openings finished in a semicircular arch

between the nave and altar apse; semicircular niche placed in the northern wall for a secondary altar; a rostrum placed on the western side with a concrete platform supported by metallic poles; inscription on a plate placed on a balustrade: “The choir was worked on the expenses of the curator during year 1946. Praise the Lord – Tomus Foltin, Oprea Ioan, Tomus Ioan, Popa Ion, Ciura Iosif, Suba Ioan, Oiada Stefan, Ciura Gh. Jun, Zlagneanu Francisc, Cimpanar Nicolae”. The pavilion room is covered by an a vella archway. The facades are plastered and painted, articulated through flat pillars; the windows are completed in a semicircular arch emphasized through plastered flat arches (2 south, 3 east apse, 3 north); cornice profiled under the roof. The facades of the pavilion have a window both on the east and west and a door on the south (today is walled), with voids finished in en panier arch with profiled surrounds. Gable roof;

– the bell tower has a square shape, slightly pyramidal in its elevation, 6 levels separated by wood platforms; rectangular windows that are narrow at levels 2 and 3; circular voids in the middle of the former clock faces; plastered and painted facades; the paint imitates stone bossages on the sides;

– the access in the church is done through the first level of the tower; the access to the second level of the tower is done through an outside ladder protected by a timber boards construction. Gambrel roof; the first layer covers a gallery with a timber boards balustrade and semicircular wood archways, with four small towers on the corners; the second layer covers the wooden lantern and finishes with a tall boom, with metal-sheet globe and cross;

– the pavilion has baroque woodwork: the corners are marked by pairs of curved columns, with composite column tops supporting the entablature, which is decorated with a frieze of stuccowork garland; above the door, a niche with a profiled surrounds containing a stuccowork shell;

– mural painting in tempera; on archvault of the iconostasis and on the first arch of the nave; painted by I. Dumitras, in 1972; decorative paintings; the inventory of the parish names an original painting;

– vexillum: approx. 1800; fixed on the void existing above the doors; gold-silver thread embroideries representing “Wailing of Jesus”;

– Christian icons painted on wood, 1817, painter S. Silaghi (storage). Furniture: – doors: approx. 1750: swing doors with three registers of icons (“The Good News” and Gospel

Saints), surrounded by stuccowork and golden spindles; – pulpit: suspended on the first pillar from the northern wall; curved rectangular cup of masonry;

panels with Christian symbols in plaster relief on 2 sides; – altar: approx. 1800; wooden pavilion painted in white paint with stuccowork and gold decorations

(garlands, frieze); placed on a masonry table; Empire style; – Tetrapod: approx. 1800, similar with the altar; pyramidal base with a desk for Christian icons and

baldachin supported by four columns; on the sides of the base, cavetto with painted religious representation;

– Big bell: 1923.

Simeon Balint’s grave, from the cemetery of Greek-Catholic Church The priest Simeon Balint was born on 10.09.1810 in Copaceni Village, near Turda, Cluj County. His father a Greek-Catholic parish clerk was a son of free peasants from Maramures County. Simeon Balint was a student in the primary and secondary schools in Cluj and Sibiu. He graduated Blaj Theological Seminary in 1834, where he was taught by the renowned teachers Timotei Cipariu and Ioan Rusu. After graduation, he served the Rosia Montana Church, initially as a chaplain. He was a very good friend of Avram Iancu and Axente Sever’ all three men were considered by the Austrian reports as being “the soul of Romanians”.



At the end of spring 1848, Simeon Balint, age 38, was arrested by the Hungarian authorities from Transylvania because he was considered an agitator of Romanian nation and head of the mountain people. He was imprisoned first in Abrud and then moved to Aiud. He is appointed President of the ROMANIAN NATIONAL COMMITTEE from TRANSYLVANIA on 10 December 1848 by Mr. Simion Barnutiu, prefect (general) of Auraria et Salinae Legio, a prefecture covering the area of Aries River. His Prefecture covered the area between Turda, Rimetea, Baia de Aries and Ierii Valley. He was one of the most efficient Legio commander in chief and although he was a priest, he fought in many battles and fights developed within the area of Apuseni Mountains between 1848 and 1849. One of his great achievements as a commander in chief was during the third battle of Abrud in the summer of 1849, when he managed to fight off the Hungarian troops lead by commander Kemeny, and the latter one stated “the devil should fight against priests” upon learning who was his worthy adversary. The protopope Simeon Balint died on 16 May 1880. He was buried at Rosia Montana by a Synod of Orthodox and Greek-Catholic priests that administered together the religious rite.



Mayoralty Office no. 184 (460) is the heritage house closest to the Cetate Pit.

This building was constructed in 1935 and it has the following strength structure: – Semi-basement, ground floor, first floor and mansard building; – Natural stone foundation; – The walls of the semi-basement are from natural stones and they have 50 cm in thickness; – The walls of the ground floor are from bricks and stones and they have 50 cm in thickness; – Hip roof that has a wooden framework and with profiled tiles placed on it.

Acknowledged damages and degradations:

– The absence of horizontal hydro-insulations placed at the level of the foundations base and, consequently, that results in extended dampness within all structural walls;

– The wood works placed in the roof framework are in an advanced biodegradation process. Due to its purpose, the building is properly maintained and has been recently renovated, and its current visual image is acceptable.

The Commune Cinema no. 185 (461) In order to conduct the earthworks for the technological protection in Orlea Pit, the second center considered is the communal cinema. The construction was built in early XXth Century (1900-1918):

– It consists of a ground floor and an attic, it has a natural stone foundation and bricks and stone walls of 85 cm in thickness;

– Hip roof that has a wooden framework and with profiled tiles placed on it. Acknowledged damages and degradations:

– Fissures and cracks in the ground floor walls; – The absence of horizontal hydro-insulations placed at the level of the foundations base and,

consequently, that results in extended dampness within all structural walls; – The wood works placed in the roof framework are in an advanced biodegradation process; – The outer walls at their corners and the door and windows posts have missing stones from their

structure;



– Outer plastering is removed from its support or it is degraded; – The smokestack is unsecured against horizontal movements.

House no. 186 (462)

The construction was built between 1880 and 1915 and it has the following strength structure:

– Building with semi-basement/basement, ground floor, first floor, and attic; – Natural stone foundation; – The walls of the semi-basement are made of natural stones and bricks, having 50-60 cm in thickness; – The walls of the ground and first floors are made of natural stones and bricks; – The floorings have a wooden framework; – The building has a wooden verandah placed on natural stones foundation; – Hip roof that has a wooden framework and with profiled tiles placed on it.

Acknowledged damages and degradations:

– fissures and cracks in the walls of the semi-basement and ground floor; – The absence of horizontal hydro-insulations placed at the level of the foundations base and,

consequently, that results in extended dampness within all structural walls; – The wood works placed in the roof framework are in an advanced biodegradation process; – Outer plastering is removed from its support or it is degraded; – The smokestack is unsecured against horizontal movements.



House no. 191 (463)

The construction was made between 1900 and 1940 and it has the following strength structure: – Building with a partial basement, ground floor and attic; – The foundation is made with natural stones; – The walls of the semi-basement are from natural stones, having 50 cm in thickness; – The walls of the ground floor are made from dirt placed on a wooden framework, having 25 cm in

thickness; – Hip roof that has a wooden framework and with bituminous cardboard and screen. Acknowledged damages and degradations: – fissures and cracks in the walls of the basement and ground floor; – bricks are falling from the ground-floor walls;



– The absence of horizontal hydro-insulations placed at the level of the foundations base and, consequently, that results in extended dampness within all structural walls;

– The wood works placed in the roof framework are in an advanced biodegradation process. 2. Deposit Geology 2.1. Stratigraphic Data

Rosia Montana is located within the “Golden Quadrilateral” from Apuseni Mountains, belonging to the Carpathian-Balkan province of the Alpine-Himalayan golden belt. The area hosts several epithermal and mezothermal deposits of Ag-Au, Cu-Au and Cu, associated with Badenian-Pliocene volcanic and sub-volcanic andesite-dacitic bodies. The Northern Apuseni rocks consist of marine sedimentary rocks of shallow depths, from Mezozoic, overlapping Paleozoic and Pre-Cambrian sedimentary and metamorphic rocks. The thrust faults directed towards north have crossed the southern side of Northern Apuseni during Upper Cretaceous period and formed a series of foldings. South Apuseni consists of several marphic magmatic bodies, which are probably the ocean crusts from Medium Jurassic and from marine sediments up to deltaic sediments from Upper Jurassic and Cretaceous, to include thick sequences of limestone. The sedimentary rocks developed in several sedimentary basins that were subjected to amalgamation due to the structural event occurred during Cretaceous. Several volcano-intrusive chalco-alkaline complexes developed within the subduction areas following the collision of Panonia micro-plate collision with the European continental plateau during Upper Eocene – Lower Miocene. The epithermal and mezothermal deposits of Ag-Au, Cu-Au and Cu are associated with Badenian – Pliocene andesitic-dacitic volcanic and sub-volcanic bodies that are forming intrusions into the Cretaceous foundation. The subvolcanic dacitic bodies from Rosia Montana have been included in a sequence of Cretaceous sediments formed mainly by black shales, fine sediments from Tortonian (Miocene) and tufaceous sands. The dacitic intrusions belong to Neocene. Moreover, the later andesitic agglomerates occur at the east and north sides of Rosia Montana and, according to the interpretation, they are associated with the intrusive andesitic phenomenon from Rosia Poieni, located at approx. 4 km east-north-east of Rosia Montana. The dacitic bodies formed vertical intrusions into the cretaceous sedimentary rocks and into the vent breccias (previously entitled micro-conglomerates), which subsequently have developed laterally within the upper areas along the stratigraphic boundaries. The dacitic bodies have been interpreted base on the aerial measurements as being apophises of a much deeper phelsic batolite. From spatial point of view, as associated with dacitic intrusions (both inside and along the intrusion boundaries) subvertical columns of breccias occur and they are in fact diatremes as per the latest interpretations. Rosia Montana Deposit is highly hydrothermally altered, argillization and silicification being predominant. Most of the Rosia Montana Mine Site has Cretaceous sediments. The sediments consist of black shales, limestones and aleurites, fine to coarse sandstones/greywacke and conglomerates with coarse elements. To date, the geological mappings have not made a clear distinction between the mainly fine marine sediments of Lower Cretaceous (flysch) and the sandstones and conglomerates (Molasse), discontinuous overlapped, and being of Upper Cretaceous age.



Figure no. 4

The Rosia Montana deposit has been interpreted as a massive ore deposit with a gold-silver mineralization disseminated in breccias and dacites, typical for the deposit being the great variability of the grades both within the plane and in depth. The lithology of the deposit is dominated by breccias and a series of Neocene sub-volcanic intrusions, Cetate and Carnic dacites. The dacitic bodies are interpreted as being vertically intruded and spread laterally at shallow depths. A dark-grey breccias called “Black Breccias” are participating into the geological composition of the ore together with the dacitic intrusions from Cetate and Carnic, approx. at the center of the complex, and they form a sub-vertical column. The black breccia consists of fragments of cretaceous black shales from the sedimentary succession, incorporated within the explosive deposits located at the center of marl complex. The andesitic extrusive rocks are seen as covering the northern and eastern side of the area, forming a blanket over the marl lithologic complex. The breccia types mapped within the deposit are as follows:

Vent Breccia (magma – phreatic breccias). A body of polymictic breccias surrounding the dacitic domes. Conglomerates, sandstones and aleurites occur intercalated within breccias, indicating the sedimentary rework of the breccia. The reworked breccia is well represented in Orlea where one can see wave markings on the fine rocks surface (ripple marks). Breccias contain clasts of various lithology, including black shales, sandstones, conglomerates, mica-shales with granats, quartzites, fine grain dacites as well as crystal-clasts of quartz, plagioclaz feldspar, pyroxens, and muscovite. There are no clasts of coarse porphyry dacite, suggesting the formation of the breccias before the intrusion of the dacite domes. The heterogeneity of clasts and the massive, unscreened texture of the breccias indicate the fact that their origin is rather explosive than sedimentary, while the lack of juvenile clasts show the fact that this is not a magmatic



origin. The breccias clasts have resulted from the Cretaceous sediments and the metamorphic sediment that is assumed to be located below the Cretaceous sediments. Leach and Hawke (1997) have considered the rock as being sedimentary due to the roundness of some clasts. In accordance with recent studies, most of the round clasts result from the Cretaceous conglomerates where clasts were already rounded. This rock has been initially called “micro-conglomerate”. A more adequate term would be “vent breccias”, “reworked vent breccias” respectively where the rock presents emphasized sedimentary characteristics. The rework of breccias indicates the presence of a lake, i.e. a crater (maars) that may have been formed due to the subsidence resulted after a magmatic/phreato-magmatic eruption impacting the base rock; this mechanism is well documented in the geologic literature.

Black Breccias (phreato/magmatic breccias). The black breccias are rocks of dark brown color and they are located between the dacitic bodies Cirnic and Cetate. The breccia has a matrix composed of black clay and coarse sandstone, quartz crystals, altered feldspar crystals, muscovite and biotite flakes as well as disseminated pyrite. Most of the matrix has probably formed through trituration of black shales, and that is providing the black color to the breccia. The clasts include clayed, angular up to rounded sediments and dacities. Silicifiated or vein clasts have not been observed within any of the works performed by R.M.G.C. to date. Leach and Hawkes (1997) observed the fact that adular is not present in breccia. The replacement of the black breccia precedes in this manner the alteration, but is subsequent to adularization and silicificaiton. It is assumed that the black breccia is a phreato-magmatic breccia formed when the ascendant magma contacted the phreatic waters. This type of breccia has been properly described by Lawless et. al. (1997).

Polymictic breccias (phreato-magmatic breccias). Several breccia sub-vertical bodies occur inside Cetate and Cirnic domes. These have a similar composition with black breccia, but without having that distinctive black color and high clay content. The distribution and shape of these bodies may be outlined both based on the results obtained from drillings and from conducting the re-mapping program in the underground in 2005. These breccia bodies have the same origin as black breccia, they are phreato-magmatic breccia. The phreato-magmatic breccia columns may present several breccifiation stages, with breccias that rework or cross the previous formed ones. The polymictic breccias are generally strongly altered and mineralized. It is possible to have a low porosity due to high content of clay in the black breccia slowing down hydrothermal fluids flow and consequently alteration, as compared with the mixed breccia that has a lower clay content.

Phreatic Breccia. From genetics point of view, there is another type of breccias present in the Rosia Montana Ore Deposit: phreatic breccias. The phreatic breccia is usually formed at the contact between phreato-magmatic, polymictic breccia bodies and host rocks (dacite, vent breccia, Cretaceous sedimentary). The most important distinctive elements based on which the phreatic breccia is identified are: the presence of the hydrothermal cement (consisting of silica, common sulphides, electrum) and the high frequency of voids partially or totally filled with a cross-beam, quartz crusts as well as prismatic crystals of quartz up to 3-5cm in length. The phreatic breccia is highly silicified and mineralized due to the elevated contents of hydrothermal cement. From descriptive point of view, phreatic breccias may be polymitic (they contain dacites clasts, sedimentary, metamorphic) and monomictic/dacitic (they contain mainly dacite clasts). Polymictic phreatic breccias represent in fact phreatic re-brecciations of the polymictic phreato-magmatic breccias (clasts are taken from the previously formed phreto-magmatic breccia), while the dacitic breccia constitutes the transitory contact area between breccia body and the dacitic host rock. The Rosia Montana Ore Deposit is hosted within an area of strong hydrothermal alterations. The distribution of the alteration assemblies is very complex. These may be simplified by grouping these in 3 main groups:

� argillite – sericite – pyrite (“argilica”), which generally occurs at the boundary of gold and silver mineralization areas; � silica – adularia – pyrite – sericite (“silica/potassic”), which occur regularly are the core of several mineralized areas of Rosia Montana; � chlorite – carbonate – pyrite (propylitic), altered assemblies developed at regional level in andesites.

The mineralization existing within Golden Quadrilateral includes mezothermal porphyry copper-gold deposits associated with volcanic, andesites and dacite rocks of Badenian-Pliocene (Neogene), rocks associated to some subvolcanic intrusions.



The major regional structure controlling the mineralization of the volcanic alignment is interpreted as being the major fault having the direction west-north-west, which is overlapping older faults. The breccias, the intrusions and the mineralization from Rosia Montana are interpreted as being located on a dilatational discontinuity, having East-West direction from a structure crossed by North-east – South-east directed faults. The types of mineralization identified to date at Rosia Montana are set forth below:

• disseminated gold-silver mineralization; • gold-silver mineralization hosted in veins, sometimes accompanied by a weak polymetallic mineralization.

The gold-silver mineralization from Cetate and Cirnic massives is hosted within dacites and in polymetallic breccias, and in Gauri and Igre/Tarina areas within vent breccias and Cretaceous foundation sediments. The mineralization is associated specifically in the polymictic breccia with disseminated sulphides, but it also occurs as free gold. Mineralization is disseminated in such a manner within the dacites so it occurs as veins quartz guangue and carbonates. The dating conducted to date is referencing two major stages in the development of the mineralization. The first stage is pervasive dissemination emphasized by the low values of gold obtained in dacites, as well as by the absence of intervals with no gold. The second stage is associated with the hydrothermal fluids responsible for the breccification and formation of stockwork areas that have created discontinuous areas of rich mineralization. Formation of the breccia bodies and stockwork areas has been structurally controlled. The mineralization present within the vent breccia, for instance within Orlea area is a stockwork, vein, and Peripheral-vein type. The veins are oriented in such a manner that they are reflecting the dominant structures emphasized within project area, and within Orlea area, the corresponding conjugated faults sets are determining formation of stockworks. A non-mineralized vent breccia body occurs in the south area of Cetate and Cirnic. This breccia forms a highly magnetic anomaly, being emphasized by the geophysical surveys conducted in the area, due to the magnetite resulted from the relatively fresh dacite clasts contained by the breccia. Pyrite occurs in minor quantities within breccia matrix or in the altered clasts of porphyry dacite, but it doesn’t occur in veins, except for some small calcite veins. The presence of dacite clasts unaltered by hornblende and magnetite together with mineralized clasts suggests the fact that the breccia has formed during the last stages of development of diatreme, after the main mineralization with sulphides stage. This is yet another proof on the evolution of Rosia Montana breccias that are developing in several stages that are prior, during and after mineralization. There are other gold-silver mineralizations similar to the Rosia Montana one, i.e. they are hosted in dacitic domes or maar-diatreme complexes, like Mount Leyshon Ore Deposit from Queensland (Paul et. al., 1990) and Moore Ore Deposit from Dominican Republic (Nelson, 2000). The operations have been mainly conducted in the underground, tens of Kms being excavated for opening works, especially coastal galleries in Cetate and Cirnic and also in Orlea and Tarina areas. The veins have been mined together with their adjacent areas, highly mineralized. The underground mining operations continued until 1985, and from 1970 both open pit and underground mining operations have been developed in Cetate area. The detailed geological explorations conducted by S.C. R.M.G.C. S.A. consisted of exploration drillings and reopening of ancient underground mining works within an interval comprised between the surface and level 525 in Cetate, level 517 in Cirnic, level 555 in Orlea and level 680 in Jig. The continuity of the ore deposit with a trend towards reducing grades down to the inferior limit has been emphasized within the explored interval. We would like to underline the fact that inside the explored area, there are several areas where the gold and silver mineralization is not present (black breccia) or it has low grades, below the accepted cut-off grade. Within a vertical plane, the maximum extent of the mineralized area is in Cirnic, approx. 560 m, and the minimum one in Orlea and Jig is approx. 420 m. In accordance with the results obtained after S.C. R.M.G.C. S.A. conducted detailed exploration works, the gold and silver mineralization has been identified in all rocks, except for black breccia present in an area that outlines Cetate, Carpeni, Cirnic, Cirnicel, Orlea, Jig, and Vaidoaia. Out of all collected samples, 62,248 samples containing grades over 0.6 g/t Au are present inside the model block used to calculate resources:

Table no. 1



Lithologic Type No, samples > 0,6 g/t Au Maximum grade

[g/t Au] Dacit 43,738 826

Internal Breccia 2,903 551

Explosion Breccia 14,812 1,240

Cretaceous Sedimentary 696 66

Andesite 99 5

Considering the above, in the case of Rosia Montana Ore Deposit, the deposit is interpreted as being massive with a disseminated mineralization, the waste areas being outlined through the interpretation of the results obtained after conducting the assessment of the resources, i.e. by adopting the cut-off grade of 0.6 g/t Au. Only the black breccia is considered to be a “waste” ground in the case of Rosia Montana Ore Deposit. The outline of the “waste” ground at the level of mining benches is an irregular one, being largely extended at the boundary of these pits without having an apparent vertical continuity. The extension of “waste” ground is lowering by depth; the benches located near the bottom of the pit are placed only in “useful” mineralization, except for Cetate Pit, where some waste rocks are found down to the level of the last bench. With respect to the extension of the “waste” ground, we would like to state that their separation may be performed only by establishing gold and silver grades, the proposed mining technology includes sampling and chemical assaying in advance of the mining operations performed.

2.2. Rosia Montana Ore Deposit

The Cretaceous sediments have been puckered around an axis oriented towards E-V direction and have been moved by the faults. The main directions followed by the faults are NW-SE, NE-SW and N-S and can be encountered within the aerial-magnetic interpretation of the area. Examples of faulted Cretaceous sediments may be observed on the road traveling from Rosia Montana down to Gura Rosia at approx. 3.5 km W of Rosia Montana, where black shales and limestones with grades between 60° and 150° are outlining in the east sandstones and conglomerates that have grades of 35° to 120°. The sandstones and the aleurites with grades between 75° and 150° located within another area, at approx. 800m N of the road, close to Rosia Montana, are entering into contact in the southern part with the same rocks, but with a grade of 35° to 100°. The Cretaceous sediments located east of the area, around Rosia Poieni have been deformed by the andesitic bodies that have intruded them. The sediments located between the andesitic intriusive bodies on the secondary road traveling from Rosia Poieni Pit have grades of 75° to 170°, and 65° to 290°. The Miocene intrusives dacites and breccia bodies at Rosia Montana and andesites at Rosia Poieni have been disrupted by the same faults. The magmatic-phreatic, or vent breccia has not been folded but shows a wide range of grades and strike directions due to dislocation and rotation by faults. Stratified sandstone at Orlea has grades between 005° to 045°. The stratified conglomerate and breccias near drillhole JVSD024 dips 20° towards 240°, stratified fine to coarse-grained sediments and breccias at Igre–Vaidoaia dips 45° towards 110° and similar rocks south of Vaidoiaia dip 30° towards 240°. The results of drilling and field observations suggest that the Jig breccia and dacite dip to the east at about 50°. Deformed sediments outcropping near JVSD001 consist of Cretaceous shales, the foundation to the vent breccia. Jig appears to be a small block displaced from the main Carnic dacite by faulting, but this is yet to be proven. The horizontal displacement, if this is the case, could be as much as 800 meters though it is probably less. Cos Mountain may also be a faulted block. Recent drilling at Cos indicates there is a faulted contact between Miocene reworked vent breccia and Cretaceous black shale to the east. The vent breccia to the south of Carnic-Cetate, is bounded by NW-SE and NE-SW trending faults. The faulted contact between vent breccia and Cretaceous sediments can be seen on the main road south of Corna, and on the track from the main road into Corna. The distribution of the andesitic pyroclastics and intrusives, exposed principally to the north and east of Rosia Montana also seems to be strongly controlled by NW-SE and NE-SW faults, probably controlling both their emplacement and later displacement. This control can be seen on the aeromagnetic interpretation of the area. Field mapping conducted during 2000 has confirmed much of the interpretation.



2.3. Hydrogeology of the area and of the ore The gold-silver mineralization from Cetate and Cirnic massives is hosted within dacites and in polymetallic breccias, and in Gauri and Igre/Tarina areas within vent breccias and Cretaceous foundation sediments. The mineralization is associated specifically in the polymictic breccia with disseminated sulphides, but it also occurs as free gold. The mineralization is disseminated in such a manner within the dacites so it occurs as veins quartz guangue and carbonates. The dating conducted to date is referencing two major stages in the development of the mineralization. The first stage is pervasive dissemination emphasized by the low values of gold obtained in dacites, as well as by the absence of intervals with no gold. The second stage is associated with the hydrothermal fluids responsible for the breccification and formation of stockwork areas that have created discontinuous areas of rich mineralization. Formation of the breccia bodies and stockwork areas has been structurally controlled. The mineralization present within the vent breccia, for instance within Orlea area is a stockwork, vein, and Peripheral-vein type. The veins are oriented in such a manner that they are reflecting the dominant structures emphasized within project area, and within Orlea area, the corresponding conjugated faults sets are determining formation of stockworks. In partea sudica a masivelor Cetate and Carnic, apare insa un corp de brecie intracrateriala nemineralizata. A non-mineralized vent breccia body occurs in the south area of Cetate and Cirnic. This breccia forms a highly magnetic anomaly, being emphasized by the geophysical surveys conducted in the area, due to the magnetite resulted from the relatively fresh dacite clasts contained by the breccia. Pyrite occurs in minor quantities within breccia matrix or in the altered clasts of porphyry dacite, but it doesn’t occur in veins, except for some small calcite veins. The presence of dacite clasts unaltered by hornblende and magnetite together with mineralized clasts suggests the fact that the breccia has formed during the last stages of development of diatreme, after the main mineralization with sulphides stage. This is yet another proof on the evolution of Rosia Montana breccias that are developing in several stages that are prior, during and after mineralization. Essentially, the spread of underground waters is limited to a level of weathered base rock and to the levels of soil and colluvial and alluvial formations. The deep base rock contains reduced quantities of water, with no indication on the existence of a major hydro-geological system at this level. The water content present in the base rock is limited to the faults system, not connected on large distances. The flow in the superficial hydro-geological systems is produces from the ridges of the valleys down the valey thalweg and further downstream. This circulation resulted in the formation of numerous springs and streams that are increasing their flow due to underground water releases. Several underground aquifer strata are known in the region, placed at high depths or hosted in quaternary deposits. The latter ones have low flows being closely connected to the precipitations regime. The ore deposit is established from fissured rocks, runoffs circulating through cracks, which are drained by the dense network of underground mining works. No reclaiming works are required until the level +700m is reached, as per the hydro-geological studies. There is, however, a possibility to cross ancient underground works where significant volumes of water may be encountered. It is estimated that reclaiming works are required below level +700 m due to the water infiltration from these underground works and of the aquifer existing below this level, the flow being approximated at. 7-14 l/s. Sumps are required to drain and evacuate waters at the level of work benches.

2.4. Tectonics of the area and of the ore

Recent researches on the volcanic apparatus of Rosia Montana show that its structure and evolution is complex. Several main stages are identified for the volcanic activity, as presented in “Evolutia geologica a Muntilor Metaliferi” (“Metaliferi Mountains Geologic Evolution”). The first stage corresponds to a mainly explosive phase, products of which are comprised in what is today the volcanogenic – sedimentary formation, initially entitled by Fr. Posepny (1867) “Lockalsediment”. The activity developed during this stage within the overall conditions of sinkage of north-eastern side of Metaliferi Mountains and other local tectonic sinkages, which are drawing the picture of this basin, explaining at the same time the large thickness of the formation that at the edge of the basin upon contact with the cretaceous deposits has an average thickness of approx. 200 m. The rhyolite elements of the volcanogenic-sedimentary formation represent the sole witness of these first activities. It is possible that the craterial area or the supply ditch to have been sunk even before the activity was re-launched or maybe what is even more plausible to have been destroyed completely by the activity developed during the second stage, which is actually the most important one.



The second stage marked by dacite effusions resulted in the establishment of two volcanoes in Carnic and Cetate hills. Their lava outburst on the surfaces of these hills, rested exclusively on the volcanogenic – sedimentary formation, with a thickness reaching sometimes 200 m and they are establishing the surface of these volcanic structures. The erosion destroyed most of the architectonics of this edifice where explosion products are not included in its composition. The presence of breccias at the outline of the two dacite pillars reflects the effect of ascending mechanical forces of magma that have broken some of the less coherent material of the volcanogenic – sedimentary formation. The two pillars are mainly dressed by a pelitic muddy formation that includes fragments of the pre-tertiary foundation of volcanogenic-sedimentary formation as of the dacitic rocks in course of formation. This material entitled glam penetrates unevenly both in breccia areas, as well as in the openings of neighbouring fractures. The glam is a muddy material accumulated at the bottom of the basin, a non-diagenesis fine fraction that is falling or is infiltrated by large quantities of water in the openings of the fractures system created by the effect of magma movement subsequently released by these ways through large effusions of dacite. In this manner, some of the weak consolidated rocks of the volcanogenic-sedimentray formation have been demolished and driven together with the mud flow existing in the vicinity of fractures. Subsequently, this material is re-carried mostly towards surface, together with the dacite occurrences. They have been infiltrated under pressure both in the breccia areas from the dacite or in their contact with neighboring rocks, as well as in the openings of fractures of different levels to the current erosion level. In other cases, they fill-in the spaces between the roots of the two pillars, accumulating it at the same time depending on the direction of the movement in other spaces created by their surfaces morphology. The beginning of the dacite phase corresponds with the overall raising movements of the territory and probably even with the ones of the basin, and that caused the first effusions of dacite lava to occur under aquatic conditions. The third stage, which is actually still developing is mainly explosive. This gave birth (explosions column filled with breccias where foundations and dactie elements are included). The explosive potential of this stage caused brecciafication and fissures within the entire structure that are more frequently developed in the close vicinity of these columns. The delayed development of these processes has created tubular shapes, but especially within breccifiation areas of different ages. In this manner, the main access routes have been created for the hydrothermal solutions, accompanied by the most spectacular metalo-genetic phenomena that have also demonstrated that they have occurred in several stages. The muddy material continues to be driven and during metalo-genesis in the upper parts of the structure; this being impregnated with sillicas generates compact rocks, usually poorly mineralized.

3. Physical – mechanical characteristics of rocks

One of the base factors that directly impact the stability of cut and fill technology is the physical and mechanical characteristic. The size of the dynamic parameters generated by the extraction activity (cutting, crushing, hauling and blasting equipments) is impacted by the physical – mechanical characteristics, the geo-physical properties, the fissures system (density, orientation, characteristics of fissures backfilling material) and the succession, orientation and extent of the geological formations. The mineralogical composition, structure, texture, nature of the binding material and the weathering degree impacts a wide scope of variation for the physical-mechanical properties, as presented in tables no. 2 and 3.

Table no. 2

No. Rock Apparent specific

weight �a [tf/m

3]

Internal friction angle ��[°]

Cohesion on the test bar

c [tf/m2] 1. Tuffaceous silty microconglomerate 2.2 28 130 2. Black breccia 2.4-2.5 27-28 5.7-20 3. Weathered breccia 2.31-2.44 32-33 300-800 4. Silicificated compact breccia 2.42-2.52 33-36 1,100–2,000 5. Altered dacite 2.31-2.46 30-35 480-900 6. Silicificated dacite 2.32-2.52 36-37 1,150–1,500



The mineralogical composition and structure lead to a wider scope of variation of the cohesion within the testing bar and the internal friction angle. The mechanical strength (compression, traction and double share) are presented in table no. 3.

Table no. 3

No. Rock Value

Mechanical strength Compression ��rc

[kgf/cm2]

Traction �rt

[kgf/cm2]

Double share �rf

[kgf/cm2]

1. Tuffaceous silty microconglomerate

min. 51 2,7 5,9 med. 66 5,3 9,4

max. 86 8 13

2. Weathered breccia

min. 209 71

med. 234 20 75

max. 255 80


min. 261 29 105

med. 456 54 118

max. 632 71 159


min. 122 - 29

med. 157 12 36

max. 295 17 45

5. Silicificated compact breccia

min. 280 40 102

med. 368 64 125

max. 560 84 149

6. Silicificated compact breccia

min. 713 20 170

med. 817 26 182

max. 927 55 202

7. Compact breccia with coarse elements

min. 368 49 183

med. 542 71 207

max. 726 100 223

8. Silicificated breccia with fine elements

min. 1023 51 182

med. 1229 67 198

max. 1406 83 232

9. Silicificated hard compact breccia

min. 712 57 127

med. 787 71 175

max. 899 81 225

10. Compact hard breccia with coarse elements

min. 525 88 116

med. 612 105 120

max. 718 128 123

11. Silicificated compact breccia with fine elements

min. 1090 63 228

med. 1550 90 334

max. 2167 109 372

12. Fissured altered dacite

min. 265 41 92

med. 338 54 106

max. 428 62 127



No. Rock Value

Mechanical strength Compression ��rc

[kgf/cm2]

Traction �rt

[kgf/cm2]

Double share �rf

[kgf/cm2]

13. Altered dacite min. 204 16 53

med. 313 25 74 max. 453 38 95

14. Altered dacite

min. 149 22 55

med. 182 29 58

max. 235 49 62

15. Silicificated dacite

min. 759 85 123

med. 1230 92 147

max. 1640 97 193

16. Silicificated dacite

min. 466 29 87

med. 604 58 111

max. 930 94 211

17. Silicificated dacite min. 866 43 140

med. 898 61 168 max. 934 72 226

The great influence of the alteration, fissuration, but especially of sillicification and sizing on the strength characteristics results form table no. 3, and from here it results the wide scope of variation for the mechanical strengths. The mechanical activity developed during the several stages lead to the occurrence of rutile during stage I and dacite during stage II and breccifications and fissurations within the entire structure. The tectonization, faulting, fissuration and diaclasation occurred during stage II of eruption when the dacitic body was re-placed and as it cooled down . These phenomena occurred also as a result of the vertical tilting movement. The fissures and diaclases from the eruptive rocks mass have a high frequency up to 10 fissures/m distributed within several systems, 4-5, out of which 2-3 being major. An indicative classification of rock according to their fissuration degree is presented in table 4.

Table no. 4

Fissuration Degree Average dimension of natural separation [m]

Concentration (%) of the natural separation in the massif

+300 mm +700 mm +1.000 mm Strongly fissured 0.1 ÷ 0.5 10 ÷ 70 30 5 Medium fissured 0.5 ÷ 0.8 70 ÷ 100 30 ÷ 80 5 ÷ 40 Poorly fissured 0.8 10 80 ÷ 100 40 ÷ 100

The approx. weighted ratio in accordance with the fissuration degree is: Strongly fissured rocks 15 – 20 %, medium fissured rocks 25 – 40 %, and poorly fissured rocks 50 %. The abovementioned ratios shall be valid only for the formations below the oxidation-weathering area. In selecting the cut-fill technology, the different environments of the formations that are most encountered within RMGC mine site are to be considered, i.e. for breccias and andesites. The sound travelling velocity within rocks varies between 1,000 – 1,500 m/s in sand, gravel, saturated clay, 2,000 – 3,000 m/s in marls and andesite, and 4,500 – 6,000 m/s in quartz sandstone, grantie and diabse. The oscillation travelling velocity depends also on the type of rocks and increases as the rock strength increases.



4. Mining Method and Blasting Technology

The economic development of the gold-silver ore reserves is possible only by using a high capacity mining method and a state-of-the-art technology endowment. The mining method is open pit mining conducted on desendent pit benches of 10 m in height. The 10 m height has been proposed together with the following mining equipments suitable for developing open pit mining methods:

– Ø 251 mm drilling machines having 30 ml/h drilling velocity; – 19.5 m3 bucket shovels; – CAT 992G HL Front end loaders, with 12 m3 buckets; – 425 and 358 KW bulldozers; – 150 t dump trucks

Depending on the spatial distribution of the gold and silver resources, 4 main areas have been identified as suitable for developing large open pits, as follows: � Cetate (Cetate and Carpeni), � Carnic (Carnic and Carnicel), � Orlea, � Jig.

The open pits may be developed on the slopes of Rosia Valley on depth comprised between 170 m and 370 m. Cetate Pit is located in the south-western side of the perimeter where the gold and silver resources have been discovered, at approx 600 m east of the Processing Plant. The reserves assessed in Cetate and Carpeni shall be mined in Cetate Pit. Cetate Pit has an elliptical shape, two bottoms, one in the north at level +680.00 m and one in the south at level +650.00 m.

• The southern area, represented by Cetate, developed at the level of 27 benches, between level + 920 m and level + 650 m;

• The northern area, represented by the slope of Cetate down to the boundary with Rosia Valley, developed at the level of 24 benches between level + 920 m and level + 680 m.

The final shape of the pit shall be elliptical with a total length on its north-south axis of 1,200 m and a width of 700 m on its east – west axis.



Figure no. 5 - Cetate Pit

The resources existing in Cirnic, Cirnicel and partially in Cetate shall be mined in Cirnic Pit . The pit is located in Cirnic east of Cetate Pit to mine the resources existent within this area, and for that it is necessary to remove the eastern slope of the pit, a slope with its highest level at 1,080 m. The pit is developed on the left slope of Rosia Valley, the final pit bottom being located at level +660 m in the north and +810 m in the south:

• The northern area shall have 42 benches between level + 1,080 m and level + 660 m; • The southern area shall have 17 benches between level + 980 m and level + 810 m.

Upon completion of mining works, the final shape of the pit shall be almost circular with an East to West extension of 900 m and a North to South extension of 1,100 m.



Figure no. 6 – Carnic Pit

Orlea and Jig Pits are located north on the other side of the Rosia Valley, and the ore shall be hauled on a main hauling road located west of Cetate for Orlea Pit and on a road located north of the Cetate and Cirnic Pits for Jig Pit. Orlea Pit is placed on the north-western side of Cetate and Cirnic Pits, on the eastern slope of Rosia Valley. Orlea Pit is opened on the right slope of Rosia Valley and south of the Orlea Mountain, the mining works consisting of stripping works conducted on the upper part of the slope between level 870 m and level 750 m, the pit shall have in the end two bottoms, one in the east and one in the west at the same level +660 m.

• The western area, 21 benches between level + 870 m and level + 660 m; • The eastern area, 20 benches between level + 860 m and level + 660 m

Orlea Pit shall have an elliptical shape, with an East to West extension of 1020 m and North to South extension of 460 m.



Figure no. 7 – Orlea Pit

Jig Pit is placed in the north – eastern side of Cetate and Cirnic pits, on the eastern slope of Rosia Valley. Jig Pit consists of stripping the hill slope starting from level +900 m. Jig Pit is developed on the right slope of Rosia Valley, East of Orlea Pit and within the southern slope of Jig, being the smallest pit both from horizontal and depth extension. The pit shall have two bottoms placed on a NW – SE alignment at level +820 m, and level +850 m:

Western area, 17 benches between level + 980 m and level + 820 m; Central area, 15 benches between level +1020 m and +850 m; Eastern area, 13 benches between level +1000 m and level + 870 m.

Figure no. 8 – Jig Pit

The mining areas located within the pits are in fact their benches that have been designed to have 10 m in height. The benches are placed within mixed areas of waste and ores, depending on the spatial distribution of resources. The ore benches evolve also within the designed sites both above as well as below the land.

4.1. Ore deposit opening and preparation

The open pit mining operation requires early development of ore deposit opening and preparation.



The opening works consist of performing an access way to the ore deposit and stripping the deposit, and as preparatory works: pit outlining, ensuring hauling ways and the work platforms. The access to the ore deposit for the benches located above the general level is ensured through a network of roads connected to the main hauling road. The benches located below the general level of the land are opened by performing trenches. The trench shall have the following dimensions: base width L = Rexc + 3 m, 27 m respectively. The 98% geological formations from the pit perimeters belong to the category of hard and very hard rocks that need to be blasted away by using explosions. The remaining 2% are weathered rocks – oxidized – and vegetal soil that may be removed by using mechanical cutting. The selection of the sites for the four pits, their development on the plane and in depth have been conducted by considering the economic development of the ore deposit without impacting the historic monuments, archaeological sites and other sites present in the protected areas established in Rosia Montana and in neighboring areas. The opening and mining works shall start in Cirnic. Cirnic Pit has an approx. circular shape with an E-W extension of 900 m and a N-S extension of 1100 m. the pit is opened by performing an inner half trench on which hauling roads are developed, with a double lane for the access of mining equipments and production hauling. The half trench is to be excavated from the main access road placed on the southern slope of Cirnic, up to level +1080 m. During the first stage, the mining benches are to be opened between levels +1080 m and +1020 m. for the benches between level +1020 m and +930 m, the opening of the ore deposit is to be conducted as half trenches excavated in the access road, which is located in the southern side of the mountain. In order to open benches, the mining works shall consist from the excavation of a half trench under a spiral form, starting from the southern side of the pit and down to the level +660 m (in the eastern side), and down to the level +810 m in the western side of the pit. The Cetate Pit has an elliptic shape, 1200 m in length on N-S axis and 700 m width on E-W axis. The opening of Cetate Pit is provided during the first stage within the southern side, between level +920 m and level +880 m, by excavating a half trench on which the main double lane hauling roads have been developed. The opening of the trenches located between level +830 m and level +820 m is to be done by excavating a half trench from the access that surrounds the pit in the west. The opening of the lower benches is done by continuing the main half trench descending down to level 790 m and through a spiral access road descending down to the pit bottom at the final level of the pit +650 m. The opening works conducted within the northern part of Cetate shall consist of excavating a half trench from the access road down to the bench level +760 m and a spiral half trench. The access in Orlea Pit is conducted on a hauling road located west of Cetate Pit. The pit is to be opened by performing an inner half trench. The mining benches are to be successively opened between levels +870 m and +750 m, by excavating a main half trench from the access roads located on south and south-eastern sides of the pit. After opening the upper part of the mountain, the resources placed between level +740 m and level +690 m are to be opened by excavating a half trench from the southern part of the pit descending as a spiral on the western side down to level +690 m. in order to open benches located below level +690 m, two half spiral trenches are to be excavated down in the south-eastern side of the pit until the final level of the pit +660 m is reached, and in the north-western side down to the final level of Orlea pit +660 m. After opening the upper part of the mountain, the resources placed between level +740 m and level +690 m are to be opened by excavating a half trench from the southern part of the pit descending as a spiral on the western side down to level +690 m. in order to open benches located below level +690 m, two half spiral trenches are to be excavated down in the south-eastern side of the pit until the final level of the pit +660 m is reached, and in the north-western side down to the final level of Orlea pit +660 m. The opening of Jig Pit shall be performed through the surface hauling road coming from Orlea Access Road and following Rosia Valley course until it reaches the pit site. The operations developed within Jig Pit mainly consist of performing excavations on the hill slope, the pit bottom being located at level +850 m within its south eastern side and level +820 m within its north western side. During the first stage the resources located between levels +1020 m and +900 m are to be opened first, the opening works being placed on the southern and western sides. The opening of the benches located between levels +1020 m and + 900 m is to be done by excavating a common outer half trench, from the main hauling road placed on the southern and western side.



Due to the fact that under level +900 m the mineralized area occurs as bodies SE-NW oriented separated by waste areas, the depth opening is to be conducted separately for each of these areas, by excavating spiral half trenches. The final model of the pit has an elliptic shape, extending for 600 m from East to West and 400 m from North to South, having as pit bottom levels +840 m for its western side, +850 m for its central area, and +870 m for its eastern side. Soil stripping is to be conducted by using a bulldozer, the material being loaded by using front end loaders, and hauled down to the vegetal soil stockpiles so as to be reused during closure and environmental rehabilitation works. In order to open the gold-silver ore deposit from Rosia Montana, the necessary mining works consist of performing hauling roads:

• Main hauling road to access the plant, to include ore hauling road; • Access road towards the TMF; • Access hauling roads for pit sites; • Access roads for the upper benches of the pits, trenches, half trenches, and intersections for the

opening of lower benches; • Main hauling road for transporting waste down to Cetate and Cirnic Dumps; • Hauling road connecting the pits and the low grade ore and soil stockpile.

The hauling roads and the access ramps (trenches and half trenches) shall be developed as two-lane macadam roads, the road bed being of minimum 30 m. The road bed is to be covered with crushed stones obtained after crushing waste rocks from Cetate Pit or rocks from Sulei Valley Quarry. In order to develop the road infrastructure within Rosia Montana, the following roads are to be developed:

• The main road between the processing plant and National Road DN 74A, having approx. 4.2 km in length;

• The access road towards the protected area, placed on the eastern side of Cirnic, having 0.9 km in length;

• Ring road to replace the current access road towards Rosia Poieni Mine Site, which will be placed on the eastern side of the TMF and will have approx. 6.8 km in length.

Aside these roads, the following ones are to be developed:

• Plant inner roads; • Service roads along tailings pipelines towards the open pit areas, waste dumps, and along electric

power lines. 4.2. Dislocation capacity

The annual dislocation capacity (ore + waste) is almost constant along years 1 to 9, and that is approx. 36,000 thousand t decreasing between years 10 and 13 to approx. 33,000 thousand t. The average of the annual dislocation capacity is approx. 35,000 thousand t, and that means a mining mass of 98,600 t per day. These quantities are to be obtained by working simultaneously within two pits. Several benches are to be mined within each of the two pits. The development of each pit shall be performed both in depth as well as on horizontal plane. Therefore, the minimum required grade shall be ensured within the material that is to be processed. The open pit mining operations shall be conducted selectively: waste and ore of two types, high and low grade ore. The high grade ore shall be directed towards the Processing Plant, while the low grade ore is to be stockpiled, and processed only between year 14 and year 16. The rocks existing within the perimeter of the four pits (Carnic, Cetate, Orlea and Jig) are hard and very hard rocky outcrops and they are to be dislocated only with explosives. The base dislocation technology is a blasting method that is using explosives placed in boreholes. The blasting method with explosives placed in mining rooms is less economic, being comparable with the blasting method with explosives placed in boreholes only when the bench height shall be higher than 25-30 m.



4.3. Dislocation technology 4.3.1. The geometrical parameters of the drilling works

The diameter of the borehole is 251 mm and must meet the equipments selected for this job (19.5 m3 Shovel and 150 t Dump Truck) and ensures a daily capacity of 98,600 t within a 355 working days. The boreholes shall be drilled under an angle of 650 against horizontal level. The depth shall be of 11.5 m, out of which the under-depth is 1.2 m.

DKI sad 1= (1)

where: D – borehole diameter of 251 mm, K1 – coefficient having the value equal to 6.

Anticipation (minimum resistance line) - W

DKW 2= (2) where:

D – borehole diameter of 210 mm, K2 = 25-30 for breccias; K2= 20-25 for dacites.

It results:

W = 7.50 m in breccias, W = 6.25 m in dacites.

The boreholes are placed in the horizontal plane following a square network on 3 or 4 rows (Figure no. 9). The distances between the boreholes and the borehole rows are:

a = b = 7.50 m for blasting conducted during production a = b = 3.25 m for blasting conducted for profiling.



Figure no. 9 4.3.2. The parameters for explosives loading and blasting procedures

The explosive load shall be continuous (in a column). The base explosive load shall be ammonium nitrate (ANFO), and the ignition load shall consist of a type II dynamite explosive and shall represent 5% of the base load. When the boreholes are filled with water, gel explosives or ANFO cartridges are to be used. The size of the explosive load has been established by considering the specific consumptions:

• 0.23 kg/t to blast dacites; • 0.15 kg/t to blast weathered breccias.

The load placed in a borehole shall be of 216 kg TNT for dacites and 180 kg TNT for weathered breccias, out of which ignition load is of 8 kg for dacites and 7 kg for breccias. The length of the load placed in the borehole shall be 5.32 m for dacites and 4.42 m for breccias, and the tamping length shall be of 6.18 m for dacites and 7.08 m for breccias.

Figure no. 10 4.3.3. Blasting Network

The blasting network consists of an electric caps circuit (milliseconds of delays) placed on the igniting wire from the boreholes. The load from a borehole shall be ignited in tow points: at the bottom of the borehole and below tamping. The igniting load from the two pints shall be half of the total igniting load. Each of the igniting loads is provided with an igniting wire. The P12 thread length from a borehole shall be of 27 m. A micro-delay electrical cap is to be placed on each wire. The two caps providing the ignition of the load placed in a borehole shall have the same delay. The caps are to be connected in series. The optimum delay between blasts is comprised between 17-30 milliseconds.



Figure no. 11 The number of delays has been established due to the condition imposed for a minimum seismic wave. As per the practical data, the minimum value of the seismic wave is for a maximum number of delays. The delays shall ensure a core displacement that may be achieved in one of the panel ends or in its central area depending on the conditions present at the working bench.

4.4. Estimated results of material dislocation by using explosives blasting 4.4.1. Indicators Indicators: – Production per borehole:

- 700 t for dacites, - and 864 t for breccias;

– Boreholes production: - 60 t/m for dacites, - 63 t/m for breccias.

Consumptions: – Explosives:

- 0.23 kg/t TNT equivalent for dacites, - 0.15 kg/t TNT equivalent for breccias;

– Ignition caps: - 2.8 pcs./1000 t for dacites, - 2.3 pcs./1000 t for breccias;

– P12 Igniting wire: – 3.3 ÷ 3.8 m/1.000 t; – Drilling bits:

- 1 bit/1,000 m of borehole, and in mining mass 700,000 t for dacites, - 1 bit/1,000 m of borehole, and in mining mass 846,000 t for breccias;

– Drilling rods: - 1 rod/10,000 m of borehole, and in mining mass 7,000 thousand t for dacites, - 1 rod/10.000 m of borehole, and in mining mass 8,640 thousand t for breccias.

4.4.2. The size of the material resulted after dislocation

The size of the material resulted after conducting the blasting procedure depends on the natural fissures existing in the respective rocks. For the three categories of natural fissuration of the mountain, the size is presented in the following table:



Table no. 5

Rocks Category

Size Class [cm] Average

dimension [cm] 0-20

20-40

40-60

60-80

80-90

80-100

100-120

120-140

140-160

160-180

+180

Strongly fissured

58 13 11 13 5 32.5

Medium fissured

47 14 17 5 7 2 4 4 38.6

Fine fissured

28 17 15 16 6 5 3 4 4 2 43.4

4.4.3. Placement of the blasted material • The height of the blasted material: h1 = 7-8 m • Distance (placement width)

)12( 1inf −=

h

hkAL (3)

A – width of the panel that is to be blasted, which is dependent on the number of borehole rows (3 or 4)

bnWA )1( −+= (4)

where: n – number of borehole rows, 3 or 4; b – distance between borehole rows (5.3 m to blast dacites, and 6 m to blast weathered breccias); kinf – aeration coefficient of the blasted material kinf =1.4 h – bench height h = 10 m

The following widths result for the deposition of material:

– dacites: - dacites – 3 borehole rows 16 m - dacites – 4 borehole rows 21 m;

– weathered breccias: - weathered breccias 3 borehole rows 18 m - weathered breccias 4 borehole rows 24 m.



Figure no. 12

4.4.4. Projection of material The blasted material is projected in case the geometric parameters for placing loads and the blasting technologies are not met. This has been established by using the following formula:

WnDar ×= 220 (5)

where, n represents the projection index. For dislocation blasting, n = 1. The projection distance shall be maximum 106 m for blasting dacites and maximum 120 m for blasting weathered breccias.

4.4.5. The seismic effect of blasting – the oscillation velocity of the material particle

The assessment criteria on the seismic effects of blasting are based on the main dynamic parameters of seismic vibrations represented by:

� particle travelling;



� Particle velocity and acceleration; � Oscillation frequency.

The study of these parameters correlated with the damage degree of buildings lead to the establishment of several assessment criteria on the assessment of the seismic effect of explosions on buildings. Based on these criteria several standards have been established, with the accepted levels of the vibration wave that will provide the necessary integrity of buildings. The seismic effect caused by blasting is characterized by the oscillation velocity of the material particle. The oscillation velocity depends on several factors, as mentioned above: the physical and mechanical features of the formations crossed by the seismic wave, the succession and the extent of these waves, the structural disturbances of rocks (size, succession and direction), the distance travelled by the seismic wave (distance between the blast center and measuring point), the blasting technologies, the distribution of the load and the size of the explosive load. The velocity is established by conducting on site measurements or by using the formulas provided by the specific literature. The size of the explosive load depends on: blasting capacity, frequency of explosions (daily, weekly, monthly). The large blasting capacity and the local conditions argue for the blasting works to be performed on a daily basis on several working faces from the operating pits. Measurements have been conducted within Rosia Montana Mining Perimeter, to assess the seismic effect of blastings conducted both in the underground and at the surface, starting with 1985. The measurements have been aimed at protecting the social and industrial facilities existing in the close vicinity of the mine. The major sites from seismic protection point of view are: � Piatra Corbului Protected Area (surface and underground), � PUZ CP area and Catalina-Monulesti, � Carpeni Protected Area (surface and underground), � Tau Gauri Protected Area (surface), � Orlea underground galleries, � Greek Catholic Church and its Parish House, � Simeon Balint’s grave � 4 monument houses around the current Mayoralty.

A major site that needs to be protected from seismic waves is the Roman Catholic Church. Several records have been conducted at this site to see the seismic waves produced by the blasting operations conducted in 1985 and in 2006. Seismic measurements have been conducted in 1985 (by Ipromin Bucharest) during three blasting operations developed in Cirnic, and in 2006 the seismic wave produced by one single blasting operation has been recorded (by UTC Bucharest) in Cetate Pit. The results of these measurements are presented in no. 6. The correlation coefficient k (Table no. 6) has been established by using the following formula:

3R

QkV = [cm/s] (6)

Table no. 6

No. of the blast

Explosive Quantity [kg TNT]

Distance [m]

Correlation Coefficient

k

Oscillation velocity [mm/s]

1/85 500 480 15 0.32 2/85 800 528 14 0.32 3/85 1,000 520 27 0.73 4/06 1,900 939 51 0.78

The average value of coefficient k = 30 has been used to calculate the maximum acceptable loads. It results that the formula for the calculation of oscillation velocity in case of blasting within Rosia Montana Perimeter is:



330

R

QV = [cm/s] (7)

There is no regulation adopted in Romania that would govern the protection of constructions against the seismic effect of blasting operations. Considering this, in order to protect the patrimony facilities present at Rosia Montana, the provisions of the DIN 4150/83 German Standard have been considered (table no. 7).

Table no. 7

The values for oscillation velocity (mm/s) as per DIN 4150/83 Standard

Building Type

Measuring points

Foundations The floor of the highest

level of a building < 10 Hz 10-50 Hz 50-100 Hz Orice frecventa

1. offices building or plant 20 20-40 40-50 40 2. residential building with plastered walls

5 5-15 15-20 15

3. historic buildings or other building that needs careful attention

3 3-8 8-10 8

For frequencies > 100 Hz, higher levels may be accepted

One may observe that 3 mm/s is the maximum accepted limit for the protection of historic monuments. The maximum accepted loads have been calculated, instantaneously blasted in the future pit, which ensure the seismic protection of the patrimony sites existing in the area, for which maximum oscillation velocities of 0.2 cm/s and 0.4 cm/s are accepted. In the case of micro-delayed blasts, the formula has been adjusted with a function connected to the total delay time. The following formulas have been used:

– for micro-delayed blasts

)(nfRR

KV

θ= (8)

– with explosion time > 140 milliseconds

2)(9,121)( tnnf ∆−= (9) – with explosion time < 140 milliseconds

tnnf

∆= 275,0

)( (10)

The following calculations are considered for micro-delayed blasts: � n∆t = 0.140 seconds; � n∆t = 0.600 seconds.

The values of the oscillation velocity for the following distances: 100 m, 200 m and 300 m off the sites that need to be protected, Piatra Corbului (surface and underground), PUZ CP area and Catalina-Monulesti, Carpeni



(surface and underground), Taul Gauri (surface), Orlea (underground), Greek Catholic Church and its Parish House, Simeon Balint’s grave and 4 monument houses located around the current Mayoralty, have been established by using the above formulas , in the case 6860 kg TNT are blasted per one explosion, as provided in the designed work technology. The following values of the oscillation velocity are obtained (Table no. 8).

Table no. 8

Blasting Type Distance to the center of the blast

100 m 200 m 300 m 400 m 500 m Oscillation velocity. [mm/s]

Instant 24.8 9.1 4.7 3.0 2.2

With micro-delays n∆t = 0.140 s 17.6 6.5 3.3 2.2 1.6

With micro-delays n∆t = 0.600 s 14.6 5.4 2.8 1.7 1.3

From the data presented under table no. 8, it results the fact that a 6,860 kg load may be used at distances higher than 300 m to the sites that need to be protected for conducting micro-delay blasts.

4.4.6. The volume of the gases and the overpressure within the air wave

Several toxic gases result after blasting the explosives that will be released in the air. The dissemination distance depends both on the gas volume, as well as the direction and velocity of the air currents. The gases volume reaches 150,920 l toxic gases CO equivalent through the blast of 6860 kg of explosives. The overpressure of the air wave depends on the explosives quantity used to conduct the blasting. This overpressure is established in accordance with the following formula:

32 77,287,0 AAAP ⋅+⋅+⋅= (11) where:

R

QA

3

= (12)

R - distance [m ], Q - explosion load [Kg TNT].

The calculation has been performed for the following distances 100, 200, 300, 400 and 500 m away from the explosion center and these are the results:

Table no. 9

Distance [m]

Pressure P [kgf/cm2]

100 0.2792

200 0.1024

300 0.0972

400 0.0440

500 0.0360

The pressures have been measured in the presence of an open explosive deposit protected by ground waves.

4.5. The scope of dislocation technology that is using blasting with explosives boreholes

The boreholes are to be used to blast rocks in benches of 4 and 10 m in height. The technology that is using mine holes with division in under-benches of 2 m in height is to be used for height below 4 m.



The technology that is using 125 mm in diameter boreholes may be used for excavations that have 4 and 8 m in height. The average blasting capacity of 98,600 t may be achieved depending on the position of the dacites or breccias blocks from the following lengths of the workface:

Table no. 10

Workface Location Length of the workface [m] Number of borehole rows 4 3

Dacites 227 251 Weathered breccias 187 222

The annual lengths of the workface are presented in table no. 11. Through the workface length one must understand the length of all strips/year that is corresponding to the placement of 3 or 4 borehole rows.

Table no. 11

Year Excavations

Annual length of the workface [m]

Dacites [thousand t]

Breccias [thousand t]

Dacites Breccias

Number of borehole rows 3 4 3 4 0 6,898 1,879 17,610 13,394 4,270 3,185 1 27,105 6,689 69,500 52,631 15,202 11,337 2 24,592 16,411 63,050 47,751 3,736 2,786 3 26,914 8,085 69,010 52,260 18,375 15,699 4 26,425 8,576 67,756 49,369 19,491 14,536 5 22,724 12,275 58,267 44,124 27,898 20,805 6 22,243 12,756 57,033 43,190 28,991 21,620 7 19,021 15,981 48,772 36,934 36,320 27,086 8 11,498 23,502 29,482 22,326 53,414 39,834 9 22,154 12,844 56,805 43,017 29,191 21,769

10 12,240 22,759 31,385 23,697 51,725 38,575 11 21,752 13,249 57,774 42,237 30,111 22,456 12 3,992 23,408 10,236 7,751 53,200 39,675 13 18,728 4,449 48,021 36,365 10,111 7,541 14 22,574 8,714 58,277 43,833 19,805 14,769

The special conditions existing at Rosia Montana, i.e. Cirnic, Cetate, Jig and Orlea Pits are placed in the close vicinity of Rosia Montana Commune. There are several buildings belonging to the patrimony, like: Piatra Corbului (surface and underground), PUZ CP area and Catalina-Monulesti, Carpeni (surface and underground), Taul Gauri (surface), Orlea (underground), Greek Catholic Church and its Parish House, Simeon Balint’s grave and 4 monument houses located around the current Mayoralty, a protection area being established to protect these buildings. These constructions present and advanced wear status, and their protection requires a technology that would generate minimum dynamic loads. In practice, the restrictions consist of reducing the explosive load on each blast, and the explosion is delayed with a large number of micro-delays. These restrictions are to be enforced in every pit from Rosia Montana.



The mining mass is to be extracted after conducting several detailed geological explorations consisting of drillings, sampling, including from boreholes drilled to place explosives, and chemical assays due to the distribution at the level of working benches of the ore and waste material. The boreholes are drilled so as to allow blasting with explosions on the upper bench of the working bench, the boreholes hall have 251 mm in diameter. A IRDM-M2 equipment is to be use to conduct drillings, an equipment that in the case of the rocks exisiting within the Rosia Montana Ore Deposit ensures a drilling velocity of 30-40.00 ml/hr, depending on the rock hardness. The boreholes are drilled in a square network, the distance between boreholes on a row being of 6.00 m for dacites and 6.50 m for breccias, and the distance between rows being 6.00 m for dacites and 6.50 m for breccias. The explosives are ANFO (ammonium nitrate – diesel fuel), and SLURRY emulsions, having a powder factor (breaking capacity) of 0.23 kg/t for dacites and 0.18 kg/t for breccias. Boosters are to be used as initiation loads to detonate the base explosive. The fuse is to be sequential and non-electrical NONEL caps are to be used together with a detonating wire, a technology that ensures a blasting degree that meets the capacity of the loading equipments (maximum dimension 1,250 m) and determines the projection distance of blasted rocks. Boreholes shall be drilled on a length of 12.00 m, with a 750 – 800 inclination. Boreholes similar to the ones drilled for mining operations are to be drilled to complete the outline of the pit slopes, but with a reduced quantity of explosives, with approx. 20%; the initiation is performed by using dynamite cartridges. The tamping of the borehole is to be done by using clay and detritus. The Nonel technology is to be applied for initiating the explosion. The blasting sequence is micro-delayed and starts in the center of the panel and travels towards the sides of that panel and towards the following rows, a technology that ensures significant reduction of seismic intensity and an increased efficiency of the blast. Up to 1,296 Kg AM shall be blasted during one of the blasting sequences, and following this blast 8,000 – 10,000 t of mining mass results. Approx. 7-8 mining panels are to be blasted to achieve the daily production requirements (waste and ore material), that is approx. 10 t of AM explosives.

5. The use of the blasting technologies near protected areas and historic monuments within Rosia Montana Mining Project

5.1. The basis of zoning the pits

The technology used to conduct blasting with explosives placed in boreholes presents several side effects like soil oscillation, air waves, material projections – and these effects are of different sizes, depending on the distance between blast center and the measuring locations. In order to protect the national heritage items, the respective parameters are exceeding the accepted levels for distances lower than 300 m. This criterion leads to the following zoning of the mine sites:

– Zone I: the area where the design base technology may be applied; – Zone II: the area where the blasting technology shall be altered so as to observe the accepted

dynamic parameters, an area that has also been divided as follows: Zone II C, Zone II B, Zone II A. At the current level of knowledge and measurement of the secondary effects of explosions with respect to protected areas, this zoning is temporary, and shall be adapted on a permanent basis depending on the practical results obtained during the mining operation. Starting with this zoning, it is estimated the fact that the volume of dislocated mining mass by applying the base technology shall represent approx. 85 % of the total volume and for the remaining 15 % blasting technology with explosives placed in 125 mm in diameter boreholes or in mine adits shall be used. The side effects of the pit blasts like oscillation velocity or the overpressure of the shock wave may overpressure may be controlled or lowered through a series of technical and organizational measures. The overpressure of the shock wave shall be impacted by the size of the explosive load and by the blasting technology (electrical or non electrical, instant or micro-delayed). It is hazardous to humans and to buildings with advanced wear level. The effect of the overpressure of the shock wave may be mitigated by applying the same procedures as in the case of material projection (workface direction and observance of the geometrical parameters for the placement of the load).



The seismic wave (the oscillation of the material particle) represents the second major impact on soil and buildings. It is assessed through the size of the velocity, acceleration or travelling of the material particle. The most frequently used parameter in the case of building protection is velocity. The oscillation velocity of the material particle has been adopted as parameter in outlining the two large areas from pits; the condition imposed that the velocity to be maximum 0.2 cm/s for the building closest to the blast center.

5.2. The accepted level of the oscillation velocity of the material particle 5.2.1. Characterization of area buildings

The buildings in the protected area are divided in classes, in accordance with the following criteria: – Area natural seismicity

- Maximum value of ground acceleration, - Composition and frequency of the seismic travelling;

– Local conditions (geological-technical and hydrogeological) – Importance and social use category of the building.

In accordance with P100-2006 standard, buildings belonging to all classes are present in the area, and the ones that need protection are the ones from Class I (heritage houses) and some of Class II. These buildings are located within the central area of Rosia Montana, within the protected area. From seismic point of view, the area is characterized by values of the coefficient of ag = 0.08 g and corner period of Tc = 0.7 s. The equivalence between seismic intensity presented in MKS degrees is of VI for Rosia Montana. Aside the major relevance of some of the constructions, their wear and tear is to be considered.

5.3. Determining through calculation the blasting parameters within the restricted area with respect to

explosives load depending on the oscillation velocity 5.3.1. Size of explosive load

The accepted explosive load is established by applying the abovementioned calculation formulas for each stage and bench. The calculations are made if the distances between the blast center and the measuring point shall be of 100, 200, 300, and 400 m. the measuring point shall be located at the boundary between the established protection area and the nearest heritage building. The results of the calculations on the instant blast (accepted velocities of 0.2 and 0.4 cm/sec) and for micro-delay blasts with a total duration of explosion n∆t of 140 milliseconds and 600 milliseconds are presented in the following table:

Table no. 12

Blast

Distance between blast center and the protected item 100 m 200 m 300 m 400 m 500 m

Oscillation velocity [cm/sec] 0.2 0.4 0.2 0.4 0.2 0.4 0.2 0.4 0.2 0.4

Load Size [kg TNT] Instantaneous 45 177 355 1,420 1,200 4,760 2,845 11,385 5,560 22,200 Micro-delay of n∆t ≤ 0.14

78 325 630 2,530 2,130 8,528 5,056 20,164 8,700 39,200

Micro-delay of n∆t = 0.60

352 1,407 2,820 11,236 9,500 37,947 22,500 90,000 40,000 175,790

The calculation has been conducted by using formulas (7), (8) and (9) that have been determined following the instrumental measurements. Calculations have been made in case of an accepted velocity of 0.4 cm/s provided that the experts shall consider this value taking into account the real distance of some buildings that need to be protected, located within the protected area.



From the analysis of the data resulted from calculation, the followings result: • Instant blasts are recommended at distances below 500 m from the blast center and at an accepted

velocity of 0.2 cm/s; micro-delay blasts with a large number of delay steps and long explosion period are recommended for distances below 200 m;

• Up to distances of 200 m, the classic blasting technology (10 m benches and 210 mm in diameter boreholes) must be tailored according to the needs.

5.3.2. The technological options for dislocating material within the restricted area

The options for conducting blasting with explosives are mainly determined by the size of the explosive load. A. Instant blast

Accepted velocity - 0.2 cm/s – Up to distances of 200 m – mine adits technology, with bench height of 2 m - 5 trepte – 200-400 m interval – boreholes technology, with borehole diameter of 125 mm and benches of

5 and 10 m – 400-500 m interval – boreholes technology, with borehole diameter of 210 mm Accepted velocity - 0.4 cm/s – Up to distances of 100 m – mine adits technology, in sub-benches of 2 m – Between 100-200 m – boreholes technology, with borehole diameter of 125 mm – Over 200 m – boreholes technology, with borehole diameter of 210 mm (cea din zona I)

B. Micro-delay blast with n∆t≤ 0.14 s Accepted velocity - 0.2 cm/s – Up to distances of 100 m – mine adits technology, in sub-benches of 2 m – 100-200 interval – boreholes technology, with borehole diameter of 125 mm and benches of 5

and 10 m – Over 200 m – boreholes technology, with borehole diameter of 125 mm and benches of 10 m Accepted velocity - 0.4 cm/s – Up to distances of 100 m – mine adits technology, in sub-benches of 2 m – Over 100 m – boreholes technology, with borehole diameter of 125-210 mm

C. Micro-delay blast with n∆t≤ 0.6 s Accepted velocity - 0.2 cm/s – Up to distances of 100 m – boreholes technology, with borehole diameter of 125 mm – and

benches of 5 and 10 m – Over 100 m – boreholes technology, with borehole diameter of 125 and 210 mm and benches of

10 m Accepted velocity - 0.4 cm/s – Up to distances of 100 m – boreholes technology, with borehole diameter of 125 mm – Over 100 m – boreholes technology, with borehole diameter of 210 mm in treapta normala de

10 m 5.4. Details regarding the blasting technologies to be used within areas close to protected buildings

(historic monuments) and areas 5.4.1. Mine adits technology

It is used up to 100 m away from the blast center. Depending on the duration of the blast (instant or with micro-delay), the accepted explosive size in order to generated a 0.2 cm/s velocity is 45-352 kg TNT or 177-352 kg TNT in the case of an accepted velocity of 0.4 cm/s. The technology shall use by dividing the 10 m high bench into sub-benches of 2 m. Mine adits are performed downward, in compliance with a square scheme. There are areas within the bench where the height is not 10 m and the mine adits shall be smaller. The geometrical and loading-blasting parameters are provided in table no. 13.



Table no. 13

Length of mine adit [m] 1.2 1.4 1.6 1.8 2.0

Distance between adits within the row [m] 1 1 1 1 1

Distance between rows [m] 1 1 1 1 1

Explosive load. kg/adit 0.6 0.8 1.0 1.2 1.4

Packed length [m/adit] 0.6 0.6 0.6 0.6 0.6

Maximum number of rows 3 3 3 3 3

For this technology, the explosive quantities are rather high, requiring a significant number of adits that are hardening the development of the blasting process (load, packing etc.). for this, the boreholes shall be drilled within several panels of dimensions suitable to onsite conditions and to the endowment-organization conditions. The sub-benches blasting may be conducted from the base of the bench or on all sub-benches. The technology has poor productivity and requires high levels of labor and materials: explosives 0.21-0.22 kg/t, igniting caps 0.4 pcs./t, adit production – below 2.4 t/adit meter. The only advantage is the possibility of achieving a low oscillation velocity of the particle. By dividing 90 mine adits into panels, it results a maximum load per blasting stage of approx. 126 kg of explosive. The same quantity of mining mass may be achieved with the boreholes technology, with borehole diameter of 125 mm on a 10 m high bench or by dividing the bench into two sub-benches of 5 m, in the case of micro-delay blasting at 0.6 s blasting duration and 0.4 cm/s accepted velocity.

5.4.2. Boreholes technology, with borehole diameter of 125 mm The technology may be applied by instant explosion of loads at distances longer than 200 m from the blast center (Vad = 0.2 cm/s) and longer than 100 m (Vad = 0.4 cm/s). if micro-delay blasting is used, it can be applied for distances longer than 100 m (Vad = 0.2 cm/s), when explosion duration is 0.14 s, and distances shorter than 100 m, provided that the explosion duration is 0.6 s, but with approx. 20-30 delay steps. The use of the boreholes technology, with borehole diameter of 125 mm allows the use of explosive loads per borehole smaller than in the case of boreholes of φ = 210 mm, resulting in lower production of mining mass and lower productivity per borehole meter. The reduction of the explosive load within the borehole is conducted by dividing the bench in two sub-benches of 5 m (Figure no. 13), resulting in doubling the loads for an explosion and the possibility of increasing the number of delay steps and the explosion duration.



Figure no. 13

The geometrical parameters for placing the boreholes and the parameters of loading and blasting at the 125 mm in diameter boreholes are presented in table no. 14.



Table no. 14

The length of the borehole [m] 5.85 11.5 Distance between holes on each row “a” [m] 3.2 3.2 Distance between the rows “b” [m] 3.3 3.3 Explosive load [kg/m] 10 10 Explosive Load [kg/hole] 29 60 Packed length [m/hole] 2.9 5.5 Number of rows 2 2 Ignition load Kg/hole in TNT equivalent 1.5 3.0 Number of electrical caps 1 2 Number of detonating wires 1 2 Length of the wire [m/hole] 8 20 Blasting network: combined (detonating wire + electrical caps at surface)

The load in a borehole is a column type charge. The ignition is started by using a more powerful explosive than ANFO ; the cartridge dynamite II that is resistant to water is favored. A combined blasting network is to be established – the igniting wire is placed in the borehole and electrical detonation with micro-delays is placed at the surface. A P12 type wire is placed in the borehole that has a total length of 5.85 m and two detonating wires in the borehole that has a total length of 11.5 m. the ignition load shall be placed in the borehole at the middle of the base charge (5.85 m borehole) or in two locations, at the bottom of the load and bellow the packing (11.5 m borehole). The two igniting loads (upper and lower) shall be equal in size. The number of boreholes corresponds the 0.2 and 0.4 cm/s velocities for the instant and micro-delay blast options (explosion duration of 0.14 s and 0.6 s) and benches of 5 and 10 m; the loads available in table no. 10 are presented in the following table.

Table no. 15

Item Distance from blast center:

100 m 200 m 300 m 400 m Number of Boreholes d = 125 mm

A. Oscillation velocity 0.2 cm/s

A1. Instant Blast:

Benches of 5 m 12 43 101

Benches of 10 m 6 20 47

A2. Micro-delay blast with explosion duration of 0.14 s:

Benches of 5 m cca. 3 23 76 Holes of 251 mm

Benches of 10 m 1 6 36 Holes of 251 mm

A3. Micro-delay blast with explosion duration of 0.6 s:

Benches of 5 m 13 79 Boreholes with d = 251 mm


B. Oscillation velocity 0.4 cm/s

B1. Instant Blast:

Benches of 5 m 50 Boreholes with d = 251 mm

Benches of 10 m - 23 Boreholes with d = 251 mm



Item Distance from blast center:

100 m 200 m 300 m 400 m Number of Boreholes d = 125 mm

B2. Micro-delay blast of 0.14 s:



B3 Micro-delay blast of 0.6 s:



The blasting activity conducted with explosives placed in boreholes of 125 mm in diameter and with division of the bench in sub-benches of 5 m may be independently conducted at every sub-bench, but this assumes that the access is ensured into the working platforms of each sub-bench or at the same time on the two sub-benches. The width of the working platform must ensure the necessary conditions to drill two rows of boreholes and the caving prism width of 2 m – in total 8.6 m. This width ensures the travelling of over 80 % of the material caved at the base of the bench. The dislocation of the material is conducted downwards from sub-bench no. 2 to sub-bench no. 1. The results of the dislocation conducted through blasting with explosives placed in boreholes of 125 mm in diameter and benches of 10 m or in sub-benches of 5 m are presented in the following table:

Table no. 16

Material size resulted after dislocation rocks with different fissuration levels

Rock Types Grain Size

Strongly fissured rocks

0-40 cm 67 %

40-60 cm 14 %

60-80 cm 14 %

80-100 cm 5 %

Medium fissured rocks

0-20 cm 56 %

20-40 cm 19 %

40-60 cm 13 %

60-80 cm 12 %

Poorly fissured rocks

0-20 cm 45 %

20-40 cm 15 %

40-60 cm 15 %

60-80 cm 13 %

– Distance of placement of material:

- Bench height 10-20 m, - Bench height 5-9 m.

– Projection distance: - Dar = 20 n2 W ≈ 70 m bench of 10 m, - Dar = 20 n2 W ≈ 40 m bench of 5 m.

– The size of the aerial wave is lower than the previous one that corresponded to a blast on the blasting stage of 6,860 kg of explosives in TNT equivalent.



– The size of the oscillation velocity of the particle shall be 0.2 or 0.4 m/s, a velocity that based the establishment of explosive loads for the two blasting techniques (instant or micro-delay).

– Specific consumptions: - Explosive in TNT equivalent of 0.23 kg/t; - Detonating devices 7 pcs./1,000 t; - Detonating wire: ⇒ 59 m/1,000 t (bench of 5 m); ⇒ 77 m/1,000 t (bench of 10 m).

The production resulted through a hole is

– 250 t for bench of 10 m, – 125 t in bench of 5 m. 5.4.3. The technologies and techniques used to blast the material within Rosia Montana Mining

Perimeter for each of the protected areas The mining operation conducted to develop the gold-silver resources/reserves from Rosia Montana Mining Perimeter is performed by blasting the mining mass with explosives placed in boreholes considering the fact that heritage sites are located near the mining area, and the oscillation velocity needs to be within the respective area at maximum 0.2 cm/s, which can be achieved through the implementation of special technologies. The major sites from the seismic protection point of view are set forth below:

1. Piatra Corbului (surface) – placed at the distance of 74.09 m from the south eastern boundary of Carnic Pit;

2. PUZ CP area and Catalina-Monulesti – at the distance of 473.69 m from south eastern boundary of Jig Pit;

3. Carpeni surface – placed at the distance of 187.94 m from the north western boundary of Cetate Pit; 4. Carpeni underground – placed at the distance of 105,83 m from the southern boundary of Orlea Pit; 5. Taul Gauri (surface) – placed at the distance of 240,19 m from the southern boundary of Cetate Pit; 6. Orlea (underground) – placed bellow Orlea Pit bottom; 7. Greek-Catholic Church and Simeon Balint’s grave – placed at the distance of 154,83 m from the

western boundary of Orlea Pit; 8. Parish House of Greek-Catholic Church – placed at the distance of 40,86 m from the western

boundary of Orlea Pit; 9. 4 monument houses located around current Mayoralty, placed as follows:

- Mayoralty (185) – placed at the distance of 50 m from the southern boundary of Orlea Pit; - House (184) – placed at the distance of 93.38 m from the southern boundary of Orlea Pit; - House (186) – placed at the distance of 93.68 m from the southern boundary of Orlea Pit; - House (191) – placed at the distance of 57.16 m from the northern boundary of Cetate Pit.

After correlating the distances between the sites that need to be protected and the pit workfaces with the potential accepted seismic effects, the following blasting technologies have been adopted:

– Piatra Corbului, accepted seismic effect – vmax = 0.4 cm/s: - zoning of Carnic Pit: ⇒ zone II B – here both boreholes technology, with borehole diameter of 125 mm and with

borehole diameter of 210 mm may be applied. The load per stage shall be of 630-2,820 kg; ⇒ zone II C – it is recommended that boreholes with diameter of 125 mm or boreholes with 251

mm in diameter to be used. The load per blasting stage shall be of 2,130-6,860 kg; – PUZ CP area and Catalina-Monulesti, accepted seismic effect – vmax = 0.2 cm/s for PUZ CP area

and vmax = 0.4 cm/s for Catalina-Monulesti: - zoning of Carnic Pit, common for both sites: ⇒ zone II B – where both boreholes technology, with borehole diameter of 125 mm and with

borehole diameter of 210 mm may be used. The load per blasting stage shall be of 630-2,820 kg;

⇒ zone II C – it is recommended that boreholes with diameter of 125 mm or boreholes with 251 mm in diameter to be used. The load per blasting stage shall be of 2,130-6,860 kg;



– Carpeni surface, accepted seismic effect – vmax = 0.4 cm/s: - zoning of Cetate Pit, common for several sites (Carpeni underground, Greek-Catholic Church

and Simeon Balint’s grave, 4 monument houses located around current Mayoralty): ⇒ zone II C – where boreholes technology, with borehole diameter of 125 mm in sub-

benches of 5 m with a long duration of the explosion with micro-delay and benches of 10 m. The explosive load shall be of 78-352 kg;

⇒ zone II B – where both boreholes technology, with borehole diameter of 125 mm and with borehole diameter of 210 mm may be used. The load per blasting stage shall be of 630-2,820 kg;


– Carpeni underground, accepted seismic effect – vmax = 0.4 cm/s: - zoning of Cetate Pit, common for several sites (Carpeni surface, Greek-Catholic Church and

Simeon Balint’s grave, 4 monument houses located around current Mayoralty): ⇒ zone II C – where boreholes technology, with borehole diameter of 125 mm in sub-




- zoning of Orlea Pit, common for several sites (Greek-Catholic Church and Simeon Balint’s grave, Parish House of Greek-Catholic Church, 4 monument houses located around current Mayoralty): ⇒ zone II C – where boreholes technology, with borehole diameter of 125 mm in sub-




– Greek-Catholic Church and Simeon Balint’s grave, accepted seismic effect – vmax = 0.2 cm/s pentru Greek-Catholic Church and vmax = 0.4 cm/s pentru Simeon Balint’s grave: - zoning of Orlea Pit, common for several sites (Carpeni underground, Parish House of Greek-

Catholic Church, 4 monument houses located around current Mayoralty): ⇒ zone II C –where boreholes technology, with borehole diameter of 125 mm in sub-benches

of 5 m with a long duration of the explosion with micro-delay and benches of 10 m. The explosive load shall be of 78-352 kg;



– Parish House of Greek-Catholic Church, accepted seismic effect – vmax = 0.2 cm/s: - zoning of Orlea Pit, common for several sites (Greek-Catholic Church and Simeon Balint’s

grave, Carpeni underground, 4 monument houses located around current Mayoralty): ⇒ zone II C – where boreholes technology, with borehole diameter of 125 mm in sub-






– 4 monument houses located around current Mayoralty, accepted seismic effect – vmax = 0.2 cm/s: - zoning of Cetate Pit, common for several sites (Carpeni surface and underground, Greek-

Catholic Church and Simeon Balint’s grave,): ⇒ zone II C – where boreholes technology, with borehole diameter of 125 mm in sub-




- zoning of Orlea Pit, common for several sites (Carpeni underground, Greek-Catholic Church and Simeon Balint’s grave, Parish House of Greek-Catholic Church): ⇒ zone II C – where boreholes technology, with borehole diameter of 125 mm in sub-



⇒ zone II C – it is recommended that boreholes with diameter of 125 mm or boreholes with 251 mm in diameter to be used. The load per blasting stage shall be of 2.130–6.860 kg;

– Orlea underground, accepted seismic effect – vmax = 0.4 cm/s: - zoning of Orlea Pit, common for several sites (Carpeni underground, Greek-Catholic Church and

Simeon Balint’s grave, Parish House of Greek-Catholic Church, 4 monument houses located around current Mayoralty): ⇒ zone II C – where boreholes technology, with borehole diameter of 125 mm in sub-




– Taul Gauri surface, accepted seismic effect – vmax = 0.4 cm/s: - zoning of Cetate Pit: ⇒ zone II B – where both boreholes technology, with borehole diameter of 125 mm and with

borehole diameter of 210 mm may be used. The load per blasting stage shall be of 630-2,820 kg;

⇒ zone II C – it is recommended that boreholes with diameter of 125 mm or boreholes with 251 mm in diameter to be used. The load per blasting stage shall be of 2,130-6,860 kg.

6. Outlining the scopes of the blasting operations to be conducted for Rosia Montana Mining

Project 6.1. The principles of outlining the scope of blasting operations

There are constructions and natural monuments in Rosia Montana Commune that belong to the Cultural Heritage, like: Piatra Corbului (surface and underground), PUZ CP area and Catalina-Monulesti, Carpeni (surface and underground), Taul Gauri (surface), Orlea (underground), Greek Catholic Church and its Parish House, Simeon Balint’s grave and 4 monument houses located around current Mayoralty and thus, a protection area is established.



The constructions are in an advance wear condition and their protection requires the use of a technology that will generate minimum dynamic loads. The protection of the historic area of the locality is aimed by establishing a protection area, and all works that may impact the area are strictly forbidden. Within this area, as well as within the buffer zone, no mining works are to be conducted (excavations, dumpings, backfillings etc.). The seismic protection aims that through the mining works conducted outside the protected area and of the buffer zone, no deteriorations or damages to be produced to the heritage buildings. For the seismic protection of these buildings, the maximum dynamic parameters have been adopted as follows 0.2 cm/s velocity, corresponding in accordance with MKS scale to some natural earthquakes of 1st and 2nd degree. These velocities must ensure theoretically the integrity of the most sensitive and worn heritage buildings existing at Rosia Montana.

6.2. Outlining the scope of blasting technologies

In order to outline their scopes, the formula (7) has been calculated on the variation of the oscillation velocity depending on the distance to the item that needs protection, for a maximum load per blasting stage of 7,000 kg, which is instantly blasted away.

330

R

QV = [cm/s] (7)

Figure no. 14

In this manner, two large areas have been established:

– zone I – where the technology provided under the project is to be used (boreholes that have a diameter of 251 mm in a 10 m high bench), with no limits on the load per blasting stage;

– zone II – with technological options for blasting material with limits on the explosive loads, as required by their seismic effect.



The use of adequate technologies at each of the abovementioned areas shall provide the maximum velocity near the closest constructions at 0.2 cm/s. Based on this, the zoning presented on Drawing no. 4 has been performed; on the drawing the explosive quantities that may be blasted with no hazard on the protected sites have been marked. Zone II is located within the 0-300 m distance interval from the construction that is nearer to the explosion center. Within this area, variations of the technology with extended loads, with mine adits or with boreholes with 125 mm in diameter shall be applied or the technology provided under the project shall be used but with a reduction of the explosive load per blast stage. This zone has been divided in three sub-zones, according to the distance from the site that needs protection, as follows: Zone II C - 100 m distance – where boreholes technology, with borehole diameter of 125 mm in sub-benches of 5 m with a long duration of the explosion with micro-delay and benches of 10 m. The explosive load shall be of 78-352 kg. Zone II B - 200 m distance – where both boreholes technology, with borehole diameter of 125 mm and with borehole diameter of 210 mm may be used. The load per blasting stage shall be of 630-2,820 kg. Zone II C - 300 m distance – boreholes of 125 mm in diameter (Q = 2,130 kg) or boreholes of 251 mm in diameter (Q = 6,860 kg) are recommended. In every case, the workfaces are to be directed in such a manner so as the minimum resistance line to be directed from 90 to 1,800 from the site that needs protection. Thus, in this manner, the reduction of the oscillation velocity is achieved together with the reduction of the projection hazard, and the aerial wave and the toxic releases of the blast shall not impact the dwelled area. The blasts shall be performed only during the first work shift in good weather and with no thunder-and-lightnings.

7. The forecast on the effects generated by the blasting operations on the buildings and natural

monuments located within the protected area

The calculations on performing this forecast have been made by using the results of the experimental researches conducted within Rosia Montana Mining Perimeter. The first experiments have been conducted in 1985, the blasts being performed within blasting chambers and boreholes with continuous packing. The chambers have been placed at level +957 m, and the recording points of the seismic waves with approx. 100 m below that level, inside the Roman-Catholic Church and in House no. 294 from Rosia Montana. It has resulted from the seismic measurements that at small distance from blast center, the vertical movement and velocity have been lower than their opposite radial ones. Together with lowering the work benches, differences in the radial and vertical elements shall occur, as follows:

– when the blast center shall be at the level of the constructions, these two elements shall have approximately equal values;

– when the blast center shall be located below the construction level, the vertical element shall be higher than the radial element.

With respect to their actual values, they shall be impacted by the geology of the mountain located between the blast center and the construction that needs protection, by the tectonic impacts, by the saturation degree, etc. Moreover, they shall be impacted by the direction of the mining blocks against the construction that needs protection (on the caving direction, opposed to that direction or in crosswise direction). The transmission of the seismic effect generated by the blasts from the center to the construction that needs protection is impacted by several factors, among which we would like to mention:

– geology of the mountain; – travelling direction; – land morphology.

The mitigation of the seismic impact produced by a blasting operation has different values on certain directions, and preferred routes exist or routes where the mitigation is maximum. The mitigation coefficient is a value that may be established through experiments. In order to assess the effects of the blasting explosions from the pits of Rosia Montana on the constructions and natural monuments existing within the protected area or on other heritage buildings, the assumption that the



seismic effect shall be transmitted through an homogenous environment has been adopted, and the only mitigation of the effect is produced by the distance between the building and the blast center; it results a maximum velocity of 0.2 cm/s within construction area. The adoption of this assumption includes an additional safety coefficient, due to the fact that the geological environment is expected to contribute to the supplementary mitigation of the seismic effect generated by blasts.

7.1. Monitoring the dynamic parameters

For the seismic protection of the heritage items, a permanent seismic surveillance shall be established for the blasting operations that are to be conducted within the future pits. On this, a fixed network of digital seismographs (drawing no. 4) shall be created; these seismographs shall be placed at the main sites that need protection. Also, a mobile network of mobile seismographs shall be created, and these seismographs shall be placed on a longitudinal profile between the site that needs protection and the blasts center. The mobile seismic stations shall be used to create the initial database based on which the final network for determining the non-hazardous load shall be established, before reaching the Zone II, and therefore the conditions for adopting additional measures are created in this manner, so as to ensure the protection of constructions existing within the protected area. Each of the fixed seismographs shall be endowed with an installation (antenna) allowing it to transmit real time data to a main station where these data are to be stored and processed. The seismographs networks shall become operational together with the first blasting procedures developed in the pits and shall remain operational until the end of mine life. After each blasting, the main station shall present a report with the assessment on the seismic effect recorded by the network.

7.2. Monitoring objectives – to determine the size of the significant dynamic parameters of the waves generated by the industrial

explosions developed in Carnic, Cetate, Jig and Orlea Pits at 100, 200, 300 and 400 m away from the blast center.

– to process the data obtained during industrial activity developed at the pits from Rosia Montana and to establish the variation law of the dynamic parameters of the seismic oscillations (seismic effect mitigation coefficient).

8. Conclusions and Proposals

The issue of using explosives at engineering works and to quantify the effects generated by explosions on civil or industrial constructions located within the impact area of these explosions has been in time the subject of many studies and researches that have been developed in order to adopt technical norms or indications through which this activity could be regulated. For Rosia Montana Mining Perimeter, specific researches on establishing the effects of blasting technologies that are using explosives to blast the mining mass have been conducted during 80s, and their results have been materialized in a paper entitled “The study on the open pit mining technology within NAPOLEON and CORHURI Stockworks area and the effects of blastings on the neighboring area and buildings”. The geo-mechanical researches on the impact of open pit blasting on Rosia Montana buildings have been re-launched in 2006, when expert teams from S.C. IPROMIN S.A. Bucharest and Technical University of Civil Engineering Bucharest have jointly conducted a study on the blasting effects on several representative buildings from Rosia Montana Protected Area, together with several instrumental surveys of the building vibrations. The main objective of the program has been to acknowledge the effects of the blasting explosions produced in the mining areas from the immediate vicinity of Rosia Montana on buildings in general and on heritage buildings in particular. The oscillation velocity within the heritage buildings area has been measured during these investigations, and one of the recording points has been placed within the area of current Mayoralty. The results of the studies on rocks mechanics from 1980 and 2006 have been used to establish the potential blasting technologies for Rosia Montana, by starting with the requirements that the secondary effects on buildings would not determine their damage or deterioration. The constructions from Rosia Montana Protected Area, current Mayoralty and the group of houses located around this institution have been considered during the 2006 work.



Within this work, starting with the results of the geo-mechanical studies conducted in the past and with some theoretical considerations, the identification of the technical solutions on the blasting technology was aimed, technical solutions that would ensure the protection of major sites located within the project impact areas, other than the Rosia Montana Protected Area, as follows: � Piatra Corbului Protected Area (surface and underground), � PUZ CP area and Catalina-Monulesti, � Carpeni Protected Area (surface and underground), � Tau Gauri Protected Area (surface), � Orlea underground galleries, � Greek Catholic Church and its Parish House, � Simeon Balint’s grave, � 4 monument houses located around current Mayoralty.

The sites, for which the blasting technologies and their scopes have been established, so as to remove hazards associated with the production of damages or deteriorations, are set forth below: � Very sensitive buildings with elevated seismic hazard (Greek Catholic Church and its Parish House,

monument houses located around current Mayoralty); � constructions (Simeon Balint’s grave, Tau Gauri Protected Area); � natural monuments (Piatra Corbului Protected Area); � ancient mining works (zona Catalina-Monulesti, Orlea underground galleries, Carpeni Protected

Area). For the protection of constructions with special relevance, it has been adopted the conditions to have a maximum oscillation velocity near the site to be protected of 0.2 cm/s. In the case of natural monuments and ancient mining works, the maximum oscillation velocity has been of 0.4 cm/s. From the analysis, it results that the classical blasting technology with explosives placed in boreholes may be applied up to distances of maximum 300 m way from the closest construction. At smaller distances, in order to have a maximum oscillation velocity 0.2 cm/s near constructions, and the seismic effect to be negligible, it is necessary to adopt special options of the base technology, consisting of reduction of the diameter and length of the borehole, reduction of the explosive quantity used on the blasting bench or on blasting stage etc. The mining activity in Cetate Pit may determine an increase in the seismicity of the protected areas Taul Gauri and Carpeni, Orlea underground and, mainly, within the area of the monument houses located around current Mayoralty. For the southern side of the Cetate Pit, between the current surface and bench at 770 m, in order to protect the protected area Taul Gauri (Mausoleum), low quantities of explosive shall be used, i.e. the solutions proposed for zones II B and II C. For the north-western side of Cetate Pit, between the current surface and the designed bottom of the pit, all three options for conducting blasting operations shall be used. In this manner, the potential oscillation velocity at the level of the foundations of monument houses located around current Mayoralty (the constructions with the highest seismic rocks that may be impacted in this area) shall be of maximum 0.2 cm/s, a velocity that is not resulting in damages or deteriorations of constructions. Moreover, the same oscillation velocity shall be recorded also at surface within Carpeni Protected Area. Within the area of the Roman galleries from Orlea and Carpeni, the oscillation velocity shall be well below the accepted level of 0.4 cm/s, due to the fact that there is a need to additional protection for more sensitive site (monument houses located around current Mayoralty). The mining operation developed in Carnic Pit may generate influences on the following protected areas Piatra Corbului, Rosia Montana Protected Area and Catalina-Monulesti Gallery. For the protection of these sites, the blasting technology to be applied within the pit’s south-eastern and north-eastern sides shall consist of reduction of the explosive quantity per blasting stage. In this manner, it is expected to have a maximum oscillation velocity at the surface of Piatra Corbului protected area of 0.4 cm/s, and at Catalina-Monulesti Gallery, corroborated with the long distance of approx. 600 m, a maximum velocity of 0.2 cm/s.



In order to limit the seismic effects of the blasting explosions, three options of blasting operations have been proposed, options that may be applied successively as the mining operations are getting close to the sites that need adoption of several protection measures. The technological option to be applied within zone II C – maximum 100 m away from the site that needs protection – boreholes technology, with borehole diameter of 125 mm in sub-benches of 5 m with a long duration of explosion with micro-delay and benches of 10 m. The explosive load shall be of 78-352 kg. Zone II B –100-200 m away from the site that needs protection – where both boreholes technology, with borehole diameter of 125 mm and with borehole diameter of 210 mm may be used. The load per blasting stage shall be of 630-2,820 kg.

Zone II C –200-300 m away from the site that needs protection – boreholes of 125 mm in diameter (Q = 2,130 kg) or boreholes of 251 mm in diameter (Q = 6,860 kg) are recommended. In all cases, the work faces shall be oriented in such a manner so as the minimum resistance line to be directed at 90°-180° against the site that needs protection. In this manner, the reduction of the oscillation velocity is ensured together with the hazard associated with material projection, and the aerial wave and the toxic releases of the explosion shall not impact the dwelled area. The mining works developed in Jig Pit may generate seismic effects on the sites from Rosia Montana Protected Area and on Catalina-Monulesti Gallery. II B and IIC options of the blasting technology shall be applied within eastern side of the pit, between the current surface level and the level of the designed pit bottom and the maximum oscillation velocity being of 0.2 cm/s. The mining operation from Orlea Pit may generate impacts on Greek-Catholic Church and on its Parish House, on the monument houses located around current Mayoralty, on the Simeon Balint’s grave and on Carpeni protected area. For the protection of Greek-Catholic Church and on its Parish House and the monument houses located around current Mayoralty, the II A option of the blasting technology shall be applied between the current surface level and bench 660 m, i.e. the explosive quantity is reduced per blasting stage together with the diameter of the blasting holes. At high distances from the abovementioned sites, II B and IIC options are to be used, and therefore the oscillation velocity at the level of the foundations of Greek-Catholic Church and mayoralty shall be of maximum 0.2 cm/s. With respect to the other sites, Simeon Balint’s grave and Carpeni protected area, the oscillation velocity shall be well below the accepted value of 0.4 cm/s, and at this velocity the deterioration and damage of the respective sites is not an issue. The mining operation from Orlea Pit may result in impacts on the Carpeni and Orlea Roman Galleries. One can see in the cross-sections prepared on the direction of the underground mining works that the distances within the respective galleries and the workfaces of the future pits are exceeding 200 m, a situation in which the blasting technologies used to protect the surface sites will ensure the protection of underground galleries. We would like to emphasize the fact that on the seismic zoning map presenting the explosive quantities to be used at Rosia Montana, a limited area of maximum 2-3 benches is proposed in the south eastern side of Orlea Pit where II C blasting options shall be used. This restriction is imposed through the previous study conducted on the protection of constructions from Rosia Montana Protected Area. By quantifying the effects of blasting explosions on the following protected areas Piatra Corbului, Catalina-Monulesti, Carpeni, Taul Gauri, Orlea underground galleries, Greek Catholic Church and its Parish House, Simeon Balint’s grave, the monument houses located around current Mayoralty, the following measures are proposed to be also adopted: � implementation of a monitoring system consisting of a fixed network of digital seismographs with

three elements placed at the main sites to be protected and a mobile network consisting of three mobile seismographs placed on a longitudinal profile between the site to be protected and the blasts center;

� launching the mining activities within the pits in areas located at approx. 300 m from the closest site to be protected and instrumental verification of the blasting technologies that are using explosives placed in boreholes.



S.C. IPROMIN S.A. Bucharest

Final Page

Paper:


Contains:

90 (ninety) pages, out of which: 16 (sixteen) tables in text, 14 (fourteen) figures in text 8 (eight) enclosed drawings

The paper has been prepared and disseminated as follows: – 2 copies – S.C. ROSIA MONTANA GOLD CORPORATION S.A., – 1 copy – S.C. IPROMIN S.A. BUCURESTI

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