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Catastrophic cases of methane explosion during exploratory drilling within the Bełchatów ortholignite deposit have led to testing for methane in other Polish ortholignite mining areas, as well as in the Złoczew deposit, where it is planned to begin mining operations. Initial tests have shown Złoczew lignite to have the highest methane content among the Polish deposits so far studied, comparable with lignite from the Bełchatów deposit, with a methane capacity in excess of 2.5 dcm3/kg at a pressure of 10 bar. Based on the computed values of the Langmuir constant, a determination was made of the quantity of methane that can be desorbed from a pressure of 10 bar to 1 bar, as well as the residual methane content. For all of the tested samples, the residual methane content is between 30 and 50% of the sorption capacity at a pressure of 10 bar. The thermal sorption equations were used to compute values of the limiting isosteric heat of adsorption. Higher values of the heat of adsorption at zero surface capacity may indicate the presence of a small quantity of micro-pores. In the case of the samples with the highest sorption capacity, the limiting isosteric heats of adsorption are low, indicating a low proportion of micro-pores in the lignite. This was confirmed by tests of nitrogen adsorption at 77 K. The proportion of micro-pores in the studied lignites is 2–3%, while the dominant pore fraction is the meso-pores, which in lignite from the Złoczew and Bełchatów deposits account for 50–66% of total pores. It is concluded that the significant adsorption of methane in the ortholignite occurs chiefly in meso-pores because of compression of the gas under increased orogenic pressure. A link is made between the higher methane-bearing capacity of the ortholignite deposits and the degree of gelification of the huminite components, based on simple statistical correlations between the methane sorption capacity and the content of humic gelified maceral. The results concerning methane sorption in lignite from the Złoczew deposit have enabled a preliminary classification of the methane-bearing capacity of Polish ortholignite deposits, which may also be of significance for similar deposits in other countries.

Boron minerals are a sought-after raw material. The European Union&rsquo, s total dependence on imported borates means that this has been a critical material since 2014. Due to the increased use of borates in modern economies, data on the predicted boron demand in the coming years indicate that it may become a critical element on a global scale. Formerly, the high boron content in groundwater was the basis for qualifying it as medicinal water (boric water). Nevertheless, the current information on the potential toxicity of boron and the narrow margin between deficiency and toxicity of boron in the human body has caused a tightening of the limits of this element in water intended for human consumption. For this reason, metaboric acid has lost its position as a specific component of curative waters. However, despite the fact that boron is not currently a specific component of curative waters, it is found in measureable concentrations in Polish medicinal water considered therapeutic based on other valuable specific components. High boron content in curative water may be the cause of the problems in some spas when obtaining certificates confirming the therapeutic properties of waters. Literature data indicate that waters with high boron content (above 25 mg/L) should not be freely available for drinking in pump rooms and other places in health resorts. To identify the situation with Polish health resorts, the content of boron in 248 curative water samples was analyzed. In 154 of these samples, the boron concentration was relatively low and did not exceed 5 mg/L. However, in the remaining 94 samples, the boron content exceeded 5 mg/L, and 38 samples had boron content exceeding 30 mg/L. Ten of the 248 samples of curative water had a boron concentration above 100 mg/L, which may be a potential source of boron for industrial recovery. The highest concentration of boron was noticed in a water sample from the Wysowa health resort and was 187.6 mg/L. Unfortunately, most of water intakes with a high concentration of boron (above 100 mg/L) are low-yielding wells. Based on the data collected, Rabka appears to be the best candidate for small-scale boron production in terms of boron content and water resources values.

Biomass is an important element in the energy balance in the world and plays a large role in efforts to reduce greenhouse gas emissions, and by this is a sustainable source of energy. One method of using biomass is through co-firing with hard coal and lignite in order to generate electricity. An important factor promoting the use of biomass in European Union countries is the fact that CO2 emissions from combustion are not included in the sum of emissions from fuel combustion, in accordance with the principles established in the emission trading system EU ETS. The aim of our research was to examine the possibility of using winter oilseed rape for energy purposes, grown in three research centres located in southern Poland. Two varieties of winter oilseed rape, Adam and Poznaniak, were used during laboratory tests. Analyses were carried out for siliques, seeds, and the main and lateral stem. As part of the study, the calorific value and heat of combustion were determined for 20 samples of winter oilseed rape. The highest values were obtained for seeds, while the lowest were obtained for stems. The calculated values of carbon dioxide emissions factor for the analysed samples were in most cases above 100 kg/GJ and were much higher than the emission during hard coal combustion. In addition, as part of the study, the biomass moisture, amount of ash generated in the combustion process, and the content of volatile compounds as well as carbon and sulphur were determined.

The radiological risk in natural gas industry is mostly connected with radon (Rn-222) and its progeny: Po-218, Pb-214, Bi-214, Po-214 and Pb-210. The radon activity concentration in natural gas transported by gas pipelines varies in a wide range from dozens of Bq/m3 to several thousand Bq/m3 and mainly depends on the proximity of mines and geological structure of the deposit from which natural gas is extracted and transported. The radon progeny are ion metals, which are easily adsorbed on aerosols and deposited on the inner surfaces of gas pipe and other gas processing equipment such as scrubbers, compressors, reflux pumps, control valves and product lines creating thin radioactive films. Additionally, radon progeny together with aerosols (in contrast to radon) are retained on filters. In the aftermath of successive radioactive decay of short-lived radon progeny, long-lived Pb-210 is accumulated on filters. The paper presents the study of the Rn-222, Pb-210 connected with the transport of natural gas by the gas pipeline network in Poland. In the scope of the study the measurements of activity concentration of radon (Rn-222) in the gas samples (with alpha scintillation cells), radiolead Pb-210 in spent filter cartridges and dust samples collected from the gas pipeline network (with gamma-ray spectrometry) were performed. The results show that the Rn-222 activity concentration in natural gas varies from the detection limit of the applied method (30 Bq/m3) to around 1400 Bq/m3. Generally, the Rn-222 concentration in natural gas samples fluctuate around the mean radon concentration in the air of dwellings in Poland. The elevated radon activity concentrations in natural gas of several hundreds of Bq/m3 and more are observed at locations where the gas directly comes from local gas mines or where there is a blend of the national gas with imported one. Relatively low radon concentration in imported natural gas is connected with the fact that this gas was imported from abroad. Therefore, the time elapsed from the gas extraction to the collection of samples was relatively long. In consequence, the concentration of Rn-222 in the gas significantly decreased due to radon decay (3.4 days). Additionally, the temporal variability (daily and weekly) of the radon activity concentration in the natural gas were assessed. The results show radon concentrations does not statistically change in daily or weekly time scale. The Pb-210 activity concentration in dust ("black-powder") from gas filters and spent filter cartridges is high and varies from 500 to 17000 Bq/kg and from 200 to 2900 Bq/kg respectively.

Activity concentration of 210Pb in black powder and gamma radiation dose rate related to natural gas transportation were discussed. As part of the research, the content of radiolead (210Pb) in black powder, spent filter containers, radon (222Rn) activity concentration in natural gas and gamma radiation dose were measured around selected points of natural gas transportation infrastructure in Poland. The content of some heavy metals was also analyzed. The average concentrations of 222Rn and 210Pb ranged from 30 to 1400 Bq/m3 and from around 450 to 16,000 Bq/kg, respectively. The external exposure to gamma radiation was low; the gamma radiation dose rate was at the level of background radiation or slightly exceeded it. The research demonstrated that the content of 210Pb in black powder is strongly related to radon concentration in natural gas, the volumetric flow rate of the transported natural gas and solid fraction content. Some black powder samples should be classified based on 210Pb content as low-radioactive waste.

The paper presents the study of the radioactivity connected with the transport of natural gas by the gas pipeline network in the selected points in Poland. In the scope of the study the measurements of activity concentration of radon (222Rn) in the gas samples, radiolead (210Pb) in spent filter cartridges and dust samples (black powder) collected from the gas pipeline network were performed. The results show that the 222Rn activity concentration in natural gas varies from the detection limit of the applied method (30 Bq/m3) to around 1400 Bq/m3. The 210Pb activity concentration in black powder samples and spent filter cartridges varies from 500 to 17000 Bq/kg and from 200 to 2900 Bq/kg respectively. The black powder with highest 210Pb concentration should be classified as low-radioactive waste according to nuclear regulations.

Methane observed in soil atmosphere above active and abandoned bituminous coal mines has a thermogenic (coalbed) and/or microbial (produced by anaerobic bacteria or resulted from in situ coal biodegradation) origin or it may be a mixture of gases generated from various sources. Identification of the origin of methane may support or refute the thesis on the uncontrolled migration of mine gases in rock formations followed by their emission to the atmosphere at coal extraction sites. Surface geochemical surveys were carried out in the vicinity of the decommissioned mine shafts at the Murcki-Staszic Coal Mine, located in the Upper Silesian Coal Basin (southern Poland). Over a 3-month period, measurements were carried out cyclically at 2 locations. Totally, 43 fixed geochemical probes were installed in the area of the Murcki II “Stanislaw” Shaft, in which measurements were carried out in six sessions. Next 29 probes were installed in the area of the Staszic III Shaft, where measurements were taken twice. Each measurement included concentrations of 5 components (methane, non-methane volatile organic compounds, total hydrocarbons, carbon dioxide and oxygen), which provided a total number of 1405 individual analytical determinations. For measurements, portable EcoProbe 5 instrument was used. The stable carbon isotope composition of methane and carbon dioxide was analyzed in selected 10 samples. The isotopic composition of hydrogen in methane was also measured in one sample. The comparative material consisted of eight samples of soil gases and two samples of mine gases, which were used as reference ‘soil’ gases. The isotopic analyses were conducted using a mass spectrometry method. Based on the results of our analyses, it is stated that both the Murcki II “Stanislaw” and the Staszic III shafts were properly decommissioned. The successful sealing of mine shafts prevented mine gases from migration through the shaft into the atmosphere. However, at a single geochemical probe located more than 100 m from the former shaft center, methane concentration in soil gases reached over 1 vol%. This confirms the general observation that mine gas migrates from coal seams and/or gobs through crushed rocks into the atmosphere. The stable carbon isotope analysis of methane and carbon dioxide as well as stable hydrogen isotope analysis of methane suggest that methane in the soil atmosphere is of thermogenic origin with minor contribution of microbial component.

This paper is a summary of results of environmental analysis conducted by PGI-NRI, AGH-UST within the monitoring of natural gas prospecting in unconventional deposits. All elements of natural environment were analyzed and on this basis the qualitative and quantitative impact of drilling and hydraulic fracturing of shales could be assessed. Special attention was drawn to the analysis of the physicochemical condition of post-reaction fluids, soil gas in the well pad area and drilling fluids. The results of analysis reveal that prospecting works do not create a significant environmental hazard. Some indices connected, e.g. with the noise climate lightly exceeded permissible values. Nonetheless, if extensive prospecting and production of shale gas are involved, the environmental studies need to be broadened to supplement this report.

Shale formations have been recently treated only as source rocks and sealing packages mainly of conventional deposits. At present shales, which have a considerable concentration of highly mature organic matter appearing in complexes of over 30 m thick are used as unconventional sources for natural gas production with the use of advanced drilling technologies. Natural gas production in such rock formations necessitates performing a horizontal section in the borehole and a big number of hydraulic fracturing jobs. The unconventional shale gas deposits have been prospected also in Poland for a couple of years. Exploration works mainly concentrate on a vast area passing from Pomerania through Mazowsze to the Lublin region in Poland. The analysis of the geologic analyses reveals that the most perspective are shales in the Lower Paleozoic at a depth of 2500 m in the eastern part to about 4000 m in the western part of the area. The paper is focused on the quantitative and qualitative evaluation of environmental impact of natural gas exploration works from unconventional deposits. Special attention was paid to the hydraulic fracturing jobs in shales, which create particular hazard for water and soil environment. These hazards already appear at the stage of preliminary works, when big quantities of chemicals and water for frac jobs are stored in the rig area, and then, during realization of works, when the spent hydraulic fracturing fluid may penetrate the water-bearing horizons in the caprock. The composition of fracturing fluid used in Gapowo B-1A well are given along with the results of chemical analyses of a few parts of spent fracturing fluid samples pumped out from the borehole. The fluid turned out to be high in salt (high specific electrolyte conductance (SEC) and total dissolved substances (TDS) and a high toxicity for most of the living organisms). For this reason the spent fracturing fluid should not enter the environment without control.

Natural gas extraction from shale rock necessitates hydraulic fracturing of rocks, which involves large amounts of fracture fluids made of 90.5% of water. The authors focus on feasibility of groundwater abstraction for the purpose of applying fracture fluids in wells of the Lublin Basin - area of perspective unconventional gas exploitation from the Ordovician and the Silurian shales. These data refer to the expected specific capacity of wells abstracting groundwater from main useful aquifers. Specific capacity of a well (q) belongs to high-certainty empirical parameters, characterizing water-bearing capacity of rocks at a regional scale. The spatial evaluation of q was based on respective data coming from 7 sheets of the Hydrogeological Map of Poland (scale 1:200,000) covering research area. Specific capacity q was calculated for wells abstracting water from the Upper Cretaceous, Tertiary and Quaternary aquifers in areas presented on particular sheets of the map. Authors determined the variability distribution and the cumulative probability plots of q values, indicating a range which corresponded to a sum of standard deviation (SD) above and below median (X̄), i.e. X̄ ± 1SD. On the total the interval included 68.2% of data. The results reveal that 0.6 ≤ q ≤ 40 m3h-1 per 1 meter of drawdown for the Upper Cretaceous rocks in the eastern part of the area, and 1.1 ≤ q ≤ 110 m3h-1 per 1 meter in the western part, being a result of more intense fracturing and fissuring. Owing to the scarcity of data, q values of wells screened at the Tertiary and Quaternary aquifers are given jointly for the whole area: 0.8 ≤ q ≤ 20 and 1.0 ≤ q ≤ 10 m3h-1 per 1 meter, respectively. The obtained specific capacities are high. When the wells are properly designed, their discharges may reach about ca. 100 m3h-1.

The hydraulic fracturing jobs performed on shale rocks are connected with atmospheric emissions of dusts and exhaust gases from high-power motors supplying pump aggregates used for fracturing operations and from other technological devices. The total power of motors driving technological systems depends on the specific character of deposit and well and may range between a dozen to tens of thousands kW. An exemplary set of technological systems used for frac jobs is presented in figure 1. The following substances are emitted to the atmosphere during engine operation, e.g. nitrogen oxides (NOx), sulfur dioxide (SO2), carbon oxide (CO), dust PM10, ammonia, benzo(a)pyrene (B(a)P), benzene, toluene, xylene, formaldehyde, acetaldehyde, acrolein. As a consequence admissible concentrations of these substances in air can be exceeded. The influence of dust and gaseous emissions accompanying shale rock fracturing jobs is addressed in this paper. Model analyses were performed. An exemplary model of a process used for simulating propagation of atmospheric emissions in a specified calculation area (1,150 m × 1,150 m) were based on the analysis of hydraulic fracturing jobs performed in wells in Poland and abroad. For making calculations more actual, the model was located in the Gdańsk area and was ascribed its typical meteorological and orographic parameters. In the center of this area a rig site 150 m x 150 m was distinguished. The emission field was generated by 12 high-power engines supplying pump aggregates, 1680 kW each. The time of work of particular engines was established for 52 hrs (13 frac jobs, each lasting 4 hrs). It was assumed that all engines will operate simultaneously and using 100% of their power. Attention was paid to the correct modelling of the real emission field. Technical parameters of motors and the applied fuels were characterized. Emission indices were worked out by, e.g. U.S. Environmental Protection Agency or European Environment Agency. The calculations of air pollutions from analyzed motors were performed with a mathematical modelling method using Gaussian plum. The results of calculations could be used for evaluating spatial distribution of maximum 1 hour concentrations (S1), incidence of exceeding admissible 1 hour concentration values (P(D1)), percentile 99.8 or 99.726 from 1 hour concentrations and average concentrations (Sa) for selected most important for the air quality contaminants, i.e. NOx (as NO2), SO2, CO, PM10, benzo(a)pyrene, benzene, toluene, xylene, formaldehyde, acetaldehyde and acrolein. The results of calculated air concentrations of selected substances on the rig border are listed in table 9, whereas spatial distributions of NOx and PM10 concentrations in figures 3 to 8. The analysis of the obtained results did not reveal cases of exceeding Polish emission standards. However, nitrogen oxide (NOx) or dust PM10 can be expected to exceed these values, e.g. in a situation when the total power installed in motors driving technological systems in the course of hydraulic fracking will be higher than assumed in the analyses. The results of calculations show to a significant impact of nitrogen oxides (NOx) and dust PM10 emissions on air quality. The risk that emission standards are exceeded beyond the rig area is conditioned both by technological factors (total power of operating motors, parameters of combusted fuel, reduced emission technologies applied to engines, duration of frac jobs, etc.) and a number of external factors, e.g. meteorological and orographic factors or high level of emitted substances in air within the rig area.

The study aimed at evaluating the distribution of mass in the straw of cereal species and also at assessing the straw yield and its losses resulting from the amount of the stubble left in the field. It was found empirically that the wheat culms are composed of five internodes, and in barley, triticale and oats of six. The highest straw mass per 1 cm was found in the second internode in both forms of wheat and winter triticale, whereas barley and oats gathered the highest weight in the first internode. In the southern part of Silesia species and forms of cereals differed in the straw yield, which can be arranged as follows, from the highest: winter wheat > spring wheat, winter triticale, winter barley, and oats > spring barley. Due to the specific distribution of dry matter in each of internodes of both wheat forms - winter and spring, they loose less stubble mass (22 and 24%, respectively), comparing to other cereals, especially spring barley, which loose 31% yield of straw in the stubble of 15 cm height.

In Poland all lignite mines are dewatered with the use of large-diameter wells. Drilling of such wells is inefficient owing to the presence of loose Quaternary and Tertiary material and considerable dewatering of rock mass within the open pit area. Difficult geological conditions significantly elongate the time in which large-diameter dewatering wells are drilled, and various drilling complications and break-downs related to the caving may occur. Obtaining higher drilling rates in large-diameter wells can be achieved only when new cutter bits designs are worked out and rock drillability tests performed for optimum mechanical parameters of drilling technology. Those tests were performed for a bit ø 1.16 m in separated macroscopically homogeneous layers of similar drillability. Depending on the designed thickness of the drilled layer, there were determined measurement sections from 0.2 to 1.0 m long, and each of the sections was drilled at constant rotary speed and weight on bit values. Prior to drillability tests, accounting for the technical characteristic of the rig and strength of the string and the cutter bit, there were established limitations for mechanical parameters of drilling technology: P ∈ (Pmin; Pmax) n ∈ (nmin; nmax) where: Pmin; Pmax - lowest and highest values of weight on bit, nmin; nmax - lowest and highest values of rotary speed of bit, For finding the dependence of the rate of penetration on weight on bit and rotary speed of bit various regression models have been analyzed. The most satisfactory results were obtained for the exponential model illustrating the influence of weight on bit and rotary speed of bit on drilling rate. The regression coefficients and statistical parameters prove the good fit of the model to measurement data, presented in tables 4-6. The average drilling rate for a cutter bit with profiled wings has been described with the form: Vśr= Z ·Pa· nb where: Vśr- average drilling rate, Z - drillability coefficient, P - weight on bit, n - rotary speed of bit, a - coefficient of influence of weight on bit on drilling rate, b - coefficient of influence of rotary speed of bit on drilling rate. Industrial tests were performed for assessing the efficiency of drilling of large-diameter wells with a cutter bit having profiled wings ø 1.16 m according to elaborated model of average rate of drilling. The obtained values of average rate of drilling during industrial tests ranged from 8.33×10-4 to 1.94×10-3 m/s and were higher than the ones obtained so far, i.e. from 181.21 to 262.11%.

This study was supported by Narodowe Centrum Badan i Rozwoju, Grant: Blue Gas – Polski Gaz Łupkowy, Agreement No. BG1/EKOŁUPKI/13

Owing to their properties, oil-products are environmentally noxious, especially for the ground-water environment. In the case of a break-down with an uncontrolled leakage to the environment, only part of hydrocarbons can be removed; a predominant amount of them infiltrate the soil, polluting ground- and surface waters. This results in organoleptic changes in water quality. Besides such leakages have a negative impact on flora and fauna. They accumulate in tissues of the living organisms and hardly undergo treatment. The physicochemical properties of modified porous glasses Na2O-B2O3-SiO2 are presented in the paper along with the results of experiments on their application to removing hydrocarbons from the environment. It follows from the obtained reduction of pollutions in laboratory samples, that porous glasses can be used as adsorbents for liquidating hydrocarbon pollutions from ground- and surface waters.

Drilling work, due to its character, settlement, and whole‐day service, has potential acoustic danger for the environment. The degree of influence depends on many factors, e.g., the type of drilling equipment, applied acoustic screens, localization of drilling and its surroundings, the type of drilled‐trough rocks, and applied drilling technology. The main sources of acoustic noise are motors, pumps, and current generators. The distinction can be made between some procedures that are more noisy than the normal drilling process, for example, tripping. Usually the drilling rig is poorly equipped with noise reduction installation. Experiments were carried out on eight types of drilling assemblies. The received results show that different drilling equipment has an individual influence on the environment. The evident proof of that is the azimuthal acoustic characteristic and additionally the noise level dependence from the cycle of drilling work. The level of LAeq in the surroundings of the examined drilling rig has been made. It has been proved that, due to the noise reduction, the selection of optimal settlement of the drilling rig and optional equipment is possible. In this optimalization process, the cycle of drilling work has been considered. This reduction is possible without additional acoustic protection.