Geochemical features of fossil fuel contaminants found in urban wastes (Siemianowice Śląskie, Poland)
In sludge samples collected in the "Centrum" wastewater treatment plant in Siemianowice Śląskie, Poland, the composition of aliphatic- and aromatic hydrocarbons and polar compound fractions were investigated by gas chromatography-mass spectrometry (GC-MS). Samples collected in accordance with Polish standards were extracted, the extracts were separated into fractions with preparative thin layer chromatography (TLC), which next were investigated by GC-MS. The following compound groups of the geochemical origin were identified: n-alkanes in the range of n-C14 to n-C.39, acyclic isoprenoids (mainly pristane and phytane), steranes, tri- and pentacyclic triterpanes. Based on the distribution of biomarkers and their parameters, it was established that the dominant component of extractable organic matter in sluge is petroleum material of an unspecified origin. Its geochemical features indicate that its most likely source was crude oil (or its products) of a relatively high degree of thermal maturity (catagenic stage of thermal evolution corresponding to vitrinite reflectance 0.7-0.8%). Aromatic hydrocarbons probably originated from petroleum also, though some of them can be attributed to the products of combustion or to sources such as bituminous coals, the ash from coal/biofuel combustion or coal wastes stored nearby.
Coal-waste dumps superimposed on former rubbish dump frequently undergo selfheating and selfignition of organic matter dispersed in the waste. The special conditions for plant growth generated as a result have been investigated since 2008 on the municipal dump reclaimed with coal wastes in Katowice-Wełnowiec, Poland. The plants observed most frequently where heating has occurred are Sisymbrium loeselii, Artemisia vulgaris, Sonchus arvensis, Chenopodium album, Achillea millefolium, Cirsium arvense, Amaranthus retroflexus, Atriplex nitens and Solanum nigrum. Some new, rare species such as Portulaca oleracea, first noticed in 2011, may be added. Most of encroaching species are annual, alien archeophytes and neophytes. Native species are mainly perennials. The majority of these species show a tendency to form specimens of huge size (gigantism). The abundance of emitted CO2 and nitrogen compounds is the likely cause of this. Additionally, the plants growing there are not attacked by insects. The heating of the ground liquidates the natural seed bank. After cooling, these places are seeded by species providing seeds at that very moment (pioneer species). Heated places on the dumps allow plant growth even in the middle of winter. As the seasonal vegetation cycle is disturbed, plants may be found seeding, blooming and fruiting at the same time.
Several types of coal waste (freshly-dumped waste, self-heated waste and waste eroded by rain water), river sediments and river water were sampled. The aim was to identify the types of phenols present on the dumps together with their relative abundances. Gas chromatography-mass spectrometry (GC-MS) analyses of a large number of samples (234) statistically underpin the phenol distributions in the sample sets. The largest average relative contents (1.17-13.3%) of phenols occur in the self-heated samples. In these, relatively high amounts of phenol, C1- and C2-phenols reflect the thermal destruction of vitrinite. In fresh coal waste, C2- and C3-phenols that originated from the bacterial/fungal degradation and oxidation of vitrinite particles are the most common (0.6 rel.%). Water-washed coal waste and water samples contain lower quantities of phenols. In the river sediments, the phenols present are the result of bacterial- or fungal decay of coaly organic matter or are of industrial origin.