Air Pollution VIII, C.A. Brebbia, H. Power & J.W.S Longhurst (Editors) © 2000 WIT Press, www.witpress.com, ISBN 1-85312-822-8 Environmental impact assessment of mining activities in the productive system of Basilicata region C. Cosmi\ G. D'Apuzzo^, M. Macchiato^, L. Mangiamele^, M. Salvia^ ' Istituto di Metodologie Avanzate di Analisi Ambientali - C.N.R. - 85050 Dipartimento di Ingegneria e Fisica dell'Ambiente - Universita degli Studi della Basilicata - 85100 Potenza, Italy * Dipartimento di Scienze Fisiche - Universita Federico II - 80126 Napoli, Italy Istituto Nazionale per la Fisica della Materia - Unita di Napoli, Italy Abstract In the latest years, oil extraction activities in Basilicata Region grew up rapidly, covering about the 80% of the whole regional area. These activities represent a significant part of the productive system and may have a considerable impact on the territory (ENI [1]), both in term of landscape and of public health. In the framework of a Regional Plan for Air Quality Protection and Recovery (V.Cuomo et al. [2]), it is therefore necessary to evaluate the pollutant emissions due to the two main extractive activities, gas and oil mining, and their operative phases (oil well preparation, production sampling, crude oil transportation and stabilisation, infrastructures building) (C.Cosmi et al. [3]). The Strategic Environmental Assessment (SEA) methodology was utilised to combine the available information and to characterise the environmental impacts related to each phase of the activities. Furthermore, SEA was integrated with Advanced Local Energy Planning -ALEP- methodology (C.Cosmi et al. [4]) to consider oil mining activities in the framework of the whole productive system. Air Pollution VIII, C.A. Brebbia, H. Power & J.W.S Longhurst (Editors) © 2000 WIT Press, www.witpress.com, ISBN 1-85312-822-8 222 Air Pollution VIII Introduction The regional mining activities are extended over an area of about 984.000 hectares. The areas in which such activities are much more intensive are the Val D'Agri, where the oil mining activities deeply increased since 1996, and the area between Ferrandina and Pisticci, where are mainly located gas mining activities. An oil treatment plant is being built near Corleto Perticara (Ministero dell'Industria [5]). Figure 1 represents the mining licences: at present in the Val D'Agri zone, that is the most important relatively to crude oil extraction, there are twenty locations, with four active wells. Natural gas production is about 370.000.000 nrVy, whose 87% is utilised to satisfy the endogenous demand. Crude oil production is about 7.000 barrels per day (7,5% of the national production) (Bonati G. [6]) but it was estimated that the future production of the Val d'Agri will increase to about 83.000 barrels per day (ENI [7]). There are no refineries in the region so crude oil is entirely exported to the nearest refinery of Taranto, after a pre-treatment consisting in dewatering, desulphuration and a preliminary stabilisation to separate methane (CHO . At present oil stabilisation is performed in the plant of Viggiano, which is going to be enlarged and integrated with a new plant located in Corleto Perticara. The oil pipe is not yet finished, therefore at present, crude oil transportation is mainly carried out by tank trucks. To satisfy the increasing production, many infrastructures are going to be built up: • Enlargement of the existing oil treatment plant (from the actual 7.500 barrels per day to 104.000 barrels per day); • Building of an oil pipe-line for connecting the pre-treatment plant of Viggiano to the Taranto refinery (length 136 Km, diameter 20", capacity 150.000 barrels per day); • Building of sea oil-reservoirs, to increase the present capacity up to 520.000 m ; • Settlement of twenty-five new locations for exploration and production; • Building of a network for connecting the new oil wells (length 130 km). Qualitative evaluation of the environmental impact of oil mining activities To estimate the environmental impact of mining activities, it is necessary to consider the different steps of the working process. The operative phases of gas mining are essentially extraction, desulphuration and dewatering. Crude oil mining is characterised by a more complex working cycle than gas extraction. Besides the oil extraction phases, an huge contribution to environmental damage may be also related to some relevant accidents that may occur, as oil wells blow- out and pipe-breakage. Air Pollution VIII, C.A. Brebbia, H. Power & J.W.S Longhurst (Editors) © 2000 WIT Press, www.witpress.com, ISBN 1-85312-822-8 Air Pollution VIII 223 Figure 1 Minerary licences in Basilicata Region (1998) Air Pollution VIII, C.A. Brebbia, H. Power & J.W.S Longhurst (Editors) © 2000 WIT Press, www.witpress.com, ISBN 1-85312-822-8 224 Air Pollution VIII A preliminary qualitative evaluation of the environmental impact can be carried out by compiling a correlation matrix, utilising the symbols of table 1. No Impact © Impact Low © Medium High & Potential Impact (can be reduced or cancelled in the project and execution phases) f Table 1: Qualitative classification of environmental impacts Relatively to the oil extraction phases, the correlation matrix of table 2 shows the environmental impact of each activity on the different environmental components. Oil well Plant Drilling Production Plant Coming location Mounting Sampling Dismantling into Operation Atmosphere CO © © © © © NO2 © L_ © © © © SO2 © © © © © PTS © © © © © THC © © © © © Surface © © Utilisation © Water resources © f + Soil © f © Sub-soil © f © r © Vegetation © © © © © © Fauna © © © © © © Landscape © © © © © © Public health © © © © © Noise 4 f © « f f Table 2: Correlation matrix Oil Extraction Phases - Environmental Components and Indicators At the same way, a qualitative characterisation of the impact due to pipe breakage and oil well blow-up on the main environmental components is described by the correlation matrix reported in table 3. Air Pollution VIII, C.A. Brebbia, H. Power & J.W.S Longhurst (Editors) © 2000 WIT Press, www.witpress.com, ISBN 1-85312-822-8 Air Pollution VIII 225 Pipe Breakage Blow-up Atmosphere CO © © NO2 © © SO2 © © PTS © © Benze © & ne THC © & Surfac & e Water ©-S ©-& resources Soil ©-& ©-& Sub-soil © ® Vegetation ©-& & Fauna © © Landscape & Public health © © © © Noise © © © © Table 3: Correlation matrix Accidents - Environmental Components and Indicators In relevant accidents (Kaplan S. [8]) as pipe-breakage and oil wells blow-up, the emissions may be mainly determined by the accidental combustion of the crude and from a not controlled eruption of pollutants and materials, which fall out may interest an area of many square kilometres surrounding the oil well. No data are available for a reliable estimation of the fluids mass which may be emitted, and, consequently, a quantitative evaluation of the potential environmental damage is rather difficult. Atmospheric pollutant emissions from mining activities The quantitative environmental impact assessment of mining activities was carried out taking into account either crude oil and gas mining, with their subsequent operative phases - drilling, extraction, crude oil pre- treatment. The contribution to the regional atmospheric pollutant emissions was estimated by utilising the EPA factors to calculate the amount of atmospheric pollutant emissions due to mining activities, and the CORINAIR factors for oil transportation. A first interesting result comes from the comparison between the emissions due to oil mining and gas mining. Figure 2 emphasises the difference in terms of the CO and NO% annual amount: gas extraction has the lowest values (CO and NO% emissions are respectively about 0.5% and 5% of the correspondent amount due Air Pollution VIII, C.A. Brebbia, H. Power & J.W.S Longhurst (Editors) © 2000 WIT Press, www.witpress.com, ISBN 1-85312-822-8 226 Air Pollution VIII to oil extraction). This results points out the environmental value of natural gas, that has a lower impact either in the production and in the consumption. OLMNKG ACTI/ITES Figure 2: Comparison between CO and NOx emission released by gas mining and oil mining activities As concerns oil mining, table 4 shows the annual emissions of the most interesting pollutants at local scale, pointing out the contribution of the different operative phases. Air Pollution VIII, C.A. Brebbia, H. Power & J.W.S Longhurst (Editors) © 2000 WIT Press, www.witpress.com, ISBN 1-85312-822-8 Air Pollution VIII 227 OIL MINING CO me NO, SO2 PTS voc PM ACTIVITIES [kg/ year] Location 113 1.04 8.78 841 624 NA NA 6 9 8 Plant Assembling 606 133 1.45 123 119 NA NA 1 Well Drilling 5.70 518 72.5 9.84 1.86 NA NA 2 76 7 6 Producti 14.1 NA 57.2 242 1.27 NA NA on Test 00 83 8 Transportation in 376 NA 380 NA NA 202 86 Production Test Phase Plant Dismantling 614 1.33 1.45 123 119 4 2 1 9 Pre-treatment 49.4 NA 173. 40.7 NA 679 NA 73 157 17 Transportation to 4.80 NA 10.0 NA NA 253 1.32 refinery 0 10 0 0 TOTAL 77.8 3.03 325. 51.8 4.00 3.41 1.40 07 2 104 92 5 5 7 Table 4: Atmospheric pollutant emissions due to the different phases of oil mining activities (NA: not available data) The activity with the higher release of pollutant emissions is crude oil pre- treatment, in which oil stabilisation and gas conditioning are performed. In this phase, it is also possible to produce electric energy, by means of a turboalternator. As said before, the present oil pipe doesn't connect all the oil wells with the pre- treatment plant, but the most of the oil produced is transported by tank trucks. Therefore, transportation gives a not negligible contribution to the pollutant emissions. Besides to contribute to the environmental pollution, oil transportation have also a high impact on the territory, increasing the traffic and, consequently the risk of accidents.