Open burning of wastes as the source of environmental contamination by POPs

In the paper the procedure for and results of a test study of a few persistent organic pollutants - polycyclic aromatic hydrocarbon （PAH）, polychlorinated biphenyls （PCB） and hexachlorobenzene （HCB） emission from the open burning of different types of wastes （domestic wastes, agricultural debris, landscape cleating debris, etc.） are discussed. The open burning of agricultural debris and landscape-clearing debris is widely applied in rural areas and small towns and in allotment gardens for the recovery of that part of wastes that can not be utilized for compost preparation. This process is most typical during the autumn season and to a lesser degree during spring. Burning occurs usually in bon fires. Burning modes differ depending on the volume of material burnt, the waste moisture content, the weather conditions, etc. During this process part of domestic wastes （polluted wood, paper, chipboard, films, plastics, etc.） are burned also. Investigations included the collection and preparation of combustible material, the simulation of open burning processes, particulate and gas emission sampling, chemical analysis of sample and data processing. Sampling procedures and sample preparation were agreeable to the emission sampling standards. The aerosol and vapour phases of POPs were collected by ordinary sampling train with pumping of waste gases through filter and solid sorbent （polyurethane foam）. For the measurements of PAH in emission, gas chromatography and mass spectrometry were used which make it possible to identify and determine 16 PAH compounds in the samples; this method was used for HCB determination also. Gas chromatography with ECD detector was used for PCB measurement. It was detected that the levels of PAH emission from wastes uncontrolled burning of wastes vary greatly. Influencing factors are composition and properties of refuse, temperature and mode of burning, level air supply. Generally, the increase of content of wood leads to the increase of PAH in emission. PAH emission also increased with increasing temperature of burning. The highest PAH values are characteristic of emissions from domestic refuse burning. Practically, all naphthalene, acenaphthylene, acenaphthene （from 60% to 100% of their total mass） and fluorene （14%-99%） were emitted in gaseous form.     

地下水矿化度检测的地球物理方法

传统的水文地质研究方法在进行地下水水质评价时,是通过地下水的取样进行分析化验,确定含水岩组中水的矿化度。目前,在利用已有的地质、地球物理资料进行西部地下水资源评价的研究中,鉴于大多数石油井中没有浅层地下水的水样化验资料,本文介绍一种利用石油测井数据计算地下水矿化度的方法,并将之应用于鄂尔多斯白垩系自流水盆地地下水矿化度估算。应用实例证明这种方法是较为可靠的,虽然存在一定的误差,但基本可以满足地下水矿化度分级评价的要求,从而开发了石油测井数据在水文地质中的应用,减少了地下水水质评价的资金投入,同时提高了矿化度预测的精度。     

Pump-and-treat method to remove nitrate from groundwater with liquor as the carbon source

As a common pollutant in groundwater, nitrate poses a significant threat to drinking water safety, especially in rural areas. A feasible solution to this problem must be established. In this study, a simple sand bucket was designed to investigate the capability of denitrification with liquor as the carbon source to remove nitrate from pumped groundwater, and the feasibility of the pump-and-treat method. Results showed that addition of a proper amount of liquor enhanced the growth and metabolism of denitrifying bacteria, efficiently reduced the nitrate content in pumped groundwater, and restricted the accumulation of intermediate products. The removal rate of nitrate exceeded 99% and reached about 16.0 mg/L/day when the carbon-to-nitrogen (C/N) ratio was higher than 0.8. The accumulated concentration of nitrite as an intermediate was less than 1.0 mg/L when the C/N ratio was higher than 1.5. However, acetate accumulation was significant. Considering the accumulation of intermediates, the appropriate range of the C/N ratio should be 1.5–1.8. In addition, onset and maintenance of denitrification were not significantly influenced by dissolved oxygen and pH. The pump-and-treat method can provide a convenient and practical channel for household or collective removal of nitrate from pumped groundwater in rural areas because liquor as a household drink is frequently accessible and inexpensive in many areas.     

城市地质灾害勘察中地球物理方法的应用效果

城市化是人类社会发展的必然趋势。伴随着城市的快速发展,大部分城市长期超强度开发利用资源,大量排放“三废”,导致资源破坏,环境恶化,人为产生了一系列地质灾害问题。由于城市地质灾害具有危害性、潜在性、突发性、隐蔽性、社会性等特点,因此全面加强城市防灾减灾,不但特别重要,而且十分紧迫。近年来,地球物理技术的应用范围得到了迅速地扩展。在各种城市地质灾害的监测、预报和防治工作中,地球物理方法同样可以发挥巨大的作用。这里针对崩塌、滑坡、泥石流、海水入侵、地下水资源污染、岩溶塌陷、地面沉降、地裂缝等几种常见城市地质灾害,概述了我国城市中的危害及发展现状,并结合实例介绍了地球物理方法在城市地质灾害勘察中的应用。实践证明,地球物理方法在城市地质灾害勘察的监测、探测和防治中具有特有的优势,是一个前景十分广阔的领域。     

Using a characteristic-based particle tracking method to solve one-dimensional fully dynamic wave flow

The theoretical behavior of a one-dimensional (1-D) open-channel flow is embedded in the Saint-Venant equation, which is derived from the Navier–Stokes equations. The flow motion is described by the momentum equations, in which the terms for the inertia, pressure, gravity, and friction loss are retained while all other terms are discarded. Although the problem is valid for most channel-flow scenarios, it is numerically challenging to solve because robust, accurate, and efficient algorithms are critical for models to field applications. The method of characteristics (MOC) is applied to solve the diagonalized Saint-Venant equations. Most importantly, the boundary conditions can be naturally implemented based on the wave directions. This is considered more closely related to realistic flow conditions and sufficiently flexible to handle mixed sub- and supercritical fluid flows in natural rivers. A computer model, WASH1DF, derived from the proposed numerical method, and which differs from other commercial software packages such as HEC-RAS and SOBEK, was developed. To test the accuracy of the proposed method, four benchmark problems were examined. Analytical solutions to these benchmark problems, covering a wide range of cases, were provided by MacDonald et al. (J. Hydrol. Eng. ASCE 123(11), 1041–1045, 1997). The simulations indicate that the proposed method provides accurate results for all benchmark cases, which are valid for all transient flow scenarios. Comparisons of WASH1DF with other commercially available software packages were also conducted under the same simulation conditions. The results indicate that our proposed model demonstrates high accuracy for all problems and achieves the highest simulation precision among all packages tested.     

新型等效源法在感应测井中的应用

这里引入在工程电磁场（EEF）中使用的新型等效源法（NESM）,并给出了新型等效源法模拟感应测井响应的理论推导及处理过程,模拟了感应测井在不同地质条件下的响应。新型等效源法是在广义多级技术（GMT）的基础上发展起来的,具有理论推导简单,计算速度快,计算精度高等优点。新型等效源法是半解析解法,占用计算机内存少。另外,解的可导性和光滑性比有限元法更胜一筹。采用新型等效源法对感应测井的响应进行数值模拟,并把数值模拟的结果和数值模式匹配法（NMM）进行对比,验证了新型等效源法可行性,并且精度可以随着等效源和级数项的增加而提高。新型等效源法形成的矩阵条件数比较大,应用双精度求解可以增加稳定性。     

Application of multivariate modelling to detect hydrocarbon components for optimal discrimination between two source rock types

The present study presents a multivariate procedure to reveal light hydrocarbon components which significantly distinguish between source rock thermal extracts. The two source rocks included in this study are the marine shales of the Late Jurassic Spekk Formation and the coals and paralic shales of the Early Jurassic Åre Formation offshore Mid-Norway.Because of the large number of components in the C₄–C₁₃ hydrocarbon fraction of source rock extracts a multivariate approach was required. The procedure consists of three distinct steps: (1) Principal component analysis of the whole data set for detection of non-significant individual components. This reduced the number of individual components from 46 to 22. (2) Separate principal component analysis of the two source rocks (Åre and Spekk) to detect outliers. (3) Principal component modelling of each of the two source rocks after deletion of outliers and non-discriminating variables to detect those hydrocarbon components which are most significant and robust for the separation of the two source rocks.The resulting model shows that there is a definitive compositional difference between the source rocks investigated.     

Use of a forensic geochemical technique and a hydrogeological assessment to determine the source of petroleum hydrocarbon contamination at a foreshore site in Korea

Investigations undertaken in 2013 at a foreshore site that was historically used for ship repairs in Korea indicated that soil and groundwater were contaminated with petroleum hydrocarbons over an area of 10,000 m². Groundwater investigations and modelling were undertaken to determine the characteristics of aquifers beneath the site, including the direction and rate of groundwater flow and the extent of dispersion of total petroleum hydrocarbon contamination. To identify petroleum products residing in contaminated soils, the hump of an unresolved complex mixture on the baseline found in the data of gas chromatography was used as a new method. Based on objective facts obtained from basic investigation, the current state of contamination, and discrimination of oil species, the polluter as specified in the Korean Soil Environment Conservation Act was identified.     

Thermogravimetry-differential thermal analysis coupled with chromatography as a thermal simulation experimental method and its application to gaseous hydrocarbons from different source rocks

In this paper a thermogravimetry-differential thermal analysis method coupled with chromatography （TG-DTA-GC） has been adopted to simulate the generation of gaseous hydrocarbons from different hydrocarbon source rocks such as coals, mudstones, and carbonate rocks with different maturities. The temperature programming for thermal simulation experiment is 20℃/min from ambient temperature to 700℃. As viewed from the quantities and composition of generated gaseous hydrocarbons at different temperatures, it is shown that low-mature coal has experienced the strongest exothermic reaction and the highest loss of weight in which the first exothermic peak is relatively low. Low-mature coal samples have stronger capability of generating gaseous hydrocarbons than high-mature samples. The amounts and composition of gaseous hydrocarbons generated are closely related not only to the abundance of organic carbon in source rocks, but also to the type of kerogen in the source rocks, and their thermal maturity. In the present highly mature and over-mature rock samples organic carbon, probably, has already been exhausted, so the production of gaseous hydrocarbons in large amounts is impossible. The contents of heavy components in gaseous hydrocarbons from the source rocks containing type- Ⅰ and - Ⅱ kerogens are generally high ; those of light components such as methane and ethane in gaseous hydrocarbons from the source rocks with Ⅲ-type kerogens are high as well. In the course of thermal simulation of carbonate rock samples, large amounts of gaseous hydrocarbons were produced in a high temperature range.     

The use of sediments to detect human impact on the fluvial system

Sediments have been used to detect sources of contamination in a catchment of the Port Jackson (Sydney Harbour) estuary and to evaluate the effects of different land-use practices on the fluvial environment. Mean enrichment (mean concentrations over pre-anthropogenic background) of size-normalized (<62.5 μm) aquatic sediment is 10 × for Cu, 20× for Pb and 90× for Zn adjacent to industrialized areas and 2×, 7× and 7×, respectively for these metals in highly urbanized subcatchments. Diffuse sources contribute minor metals to fluvial sediment even in the most underdeveloped subcatchment (2×, 3× and 3× for Cu, Pb and Zn respectively). Organochlorine pesticide residue concentrations parallel heavy-metal trends due to a common mixed industrial base. Effects-based sediment criteria suggest that some adverse biological impacts are probably occurring in streams flowing through the industrial areas. This interpretation is supported by sequential extraction data which show that a moderate proportion of total heavy metals, especially Zn, is associated with the more bioavailable exchangeable/adsorbed phases in these aquatic sediments. High total suspended solid loads in water downstream of one of the industrial centers, and high particle-bound Cu and Pb concentrations, suggest that most contaminants exiting the catchment do so in association with the solid phase. Received: 29 March 1999 · Accepted: 30 August 1999     

The university as a local source of expertise

The relationship between the university and the city is expressed, amongst others, by the transfer of knowledge from the university to local actors. The universitys role as a local source of knowledge is studied by analyzing the outflow of the two main knowledge assets to the local area: graduates and research results. By comparing the results from universities in the Netherlands and the United Kingdom comparative evidence is discussed.     

Gravitational potential as a source of earthquake energy

Some degree of tectonic stress within the earth originates from gravity acting upon density structures. The work performed by this “gravitational tectonics stress” must have formerly existed as gravitational potential energy contained in the stress-causing density structure.According to the elastic rebound theory (Reid, 1910), the energy of earthquakes comes from an elastic strain field built up by fairly continuous elastic deformation in the period between events. For earthquakes resulting from gravitational tectonic stress, the elastic rebound theory requires the transfer of energy from the gravitational potential of the density structures into an elastic strain field prior to the event.An alternate theory involves partial gravitational collapse of the stress-causing density structures. The earthquake energy comes directly from a net decrease in gravitational potential energy. The gravitational potential energy released at the time of the earthquake is split between the energy released by the earthquake, including work done in the fault zone and an increase in stored elastic strain energy. The stress associated with this elastic strain field should oppose further fault slip.     

Use of coliphages to evaluate water treatment processes and determine faecal contamination origin of source waters

Viral indicators were used to evaluate the effectiveness of water treatment processes and to determine the source of faecal pollution with a view to promote water source management. Water samples were collected from three critical points of the Temba, Klipdrift and Wallmansthal water treatment plants (raw water, settled water and filtered water). The viral indicator concentrations and selected physicochemical parameters were measured using standard methods. Random water samples were subjected to real-time polymerase chain reaction analyses. Subsequent to filtration, the removal efficiency of the three Waterworks was recorded as follows: 93.2, 96.1 and 95.7 % for somatic coliphages, respectively; and 69.4 and 68.4 % FRNA coliphages for Temba and Klipdrift. There was a notable 50 % reappearance of FRNA coliphages in filtered water samples from Wallmansthal. Positive correlations were observed between the physicochemical parameters and somatic coliphages, with the exception of the pH and the temperature in Wallmansthal. Both turbidity and temperature indicated positive correlations with FRNA counts from Temba and Klipdrift. Negative correlations were observed between all the physicochemical parameters and FRNA counts from Wallmansthal. The real-time polymerase chain reaction analyses revealed the persistence of GA genotype FRNA (Group II, which is of human faecal origin) in all the water samples. The MS2 genotype (Group I) and Qβ genotype (Group III) FRNA, which are of animal origin, were detected only in the raw water from Temba. Efforts should be focused on the protection of water sources and the optimisation of treatment processes in order to prevent viral persistence during water treatment.     

DIVERSITY: A new method for evaluating sensitivity of groundwater to contamination

This study outlines an improved method, DIVERSITY, for delineating and rating groundwater sensitivity. It is an acronym for DIspersion/VElocity-Rated SensitivITY, which is based on an assessment of three aquifer characteristics: recharge potential, flow velocity, and flow directions. The primary objective of this method is to produce sensitivity maps at the county or state scale that illustrate intrinsic potential for contamination of the uppermost aquifer. Such maps can be used for recognition of aquifer sensitivity and for protection of groundwater quality. We suggest that overriding factors that strongly affect one or more of the three basic aquifer characteristics may systematically elevate or lower the sensitivity rating. The basic method employs a three-step procedure: (1) Hydrogeologic settings are delineated on the basis of geology and groundwater recharge/discharge position within a terrane. (2) A sensitivity envelope or model for each setting is outlined on a three-component rating graph. (3) Sensitivity ratings derived from the envelope are extrapolated to hydrogeologic setting polygons utilizing overriding and key factors, when appropriate. The three-component sensitivity rating graph employs two logarithmic scales and a relative area scale on which measured and estimated values may be plotted. The flow velocity scale ranging from 0.01 to more than 10,000 m/d is the keystone of the rating graph. Whenever possible, actual time-of-travel values are plotted on the velocity scale to bracket the position of a sensitivity envelope. The DIVERSITY method was developed and tested for statewide use in Kentucky, but we believe it is also practical and applicable for use in almost any other area.     

Groundwater contamination source estimation based on a refined particle filter associated with a deep residual neural network surrogate

Hydrogeology Journal - Groundwater contamination source estimation (GCSE) involves an inverse process to match time-series monitoring data in sparse observation wells. It is commonly accompanied by...     

Coal as a source rock for oil: a review

The geological debate about whether, and to what extent, humic coals have sourced oil is likely to continue for some time, despite some important advances in our knowledge of the processes involved. It is clear that not only liptinites, but also perhydrous vitrinites have the potential to generate hydrocarbon liquids in the course of natural coalification. Some liptinites, especially alginite, cutinite, and suberinite, contain a higher proportion of aliphatic moieties in their structure than other liptinites such as sporinite and resinite and are, therefore, more oil-prone. It is of potential value to be able to predict the several environments of deposition in which coals with high liptinite contents or containing perhydrous vitrinites may have been formed. Review of the distribution of oil-prone coals in time and space reveals that most are Jurassic–Tertiary with key examples from Australia, New Zealand, and Indonesia. Methods based both on experimental simulations and the examination of naturally matured samples have been used to determine the order of generation of hydrocarbons from different macerals. Results are not entirely consistent among the different approaches, and there is much overlap in the ranges of degradation, but it seems probable that in the natural environment vitrinites begin to generate early, followed by labile liptinites such as suberinite, then cutinite, sporinite, and, finally, alginite.Petroleum potential may be determined by experimental simulation of natural coalification or inferred through various micro-techniques, especially fluorescence and infrared (IR) spectroscopy, or bulk techniques such as elemental analysis and ¹³C NMR spectroscopy. The latter three techniques enable a measure of the polymethylene component of the coal, which now appears to be one of the best available approaches for determining petroleum potential. No method of experimental simulation of petroleum generation from coals is without criticism, and comparative results are highly variable. However, hydrous pyrolysis, confined pyrolysis, and forms of open-system hydrous pyrolysis approach acceptable simulations.Whether, and to what degree generated liquid hydrocarbons are expelled, has long been the central problem in ‘oil from coal’ studies. The structure of vitrinite was believed until recently to contain an interconnected microporous network in which generated oil would be contained until an expulsion threshold was attained. Recent studies show the pores are not interconnected. Combined with a dynamic model of pore generation, it now seems that expulsion of hydrocarbons is best explained by activated diffusion of molecules to maceral boundaries and ultimately by cleats and fractures to coal seam boundaries. The main reason for poor expulsion is the adsorption of oil on the organic macromolecule, which may be overcome (1) if coals are thin and interbedded with clastic sediments, or (2) if the coals are very hydrogen-rich and generate large quantities of oil.The existence of oil in vitrinite is attested to by solvent extractions, fluorescence properties, and by microscopic observations of oil and bitumen. Experimental simulation of expulsion of oil from coals has only recently been attempted. The relative timing of release of generated CO₂ and CH₄ could have considerable importance in promoting the expulsion of liquid hydrocarbons but the mechanism is unclear. As it is universally agreed that dispersed organic matter (DOM) in some shales readily generates and expels petroleum, it is curious that few consistent geochemical differences have been found between coal macerals and DOM in interbedded shales.Unambiguous evidence of expulsion from coals is limited, and in particular only a few commercial oil discoveries can be confidently correlated to coals. These include Upper Cretaceous Fruitland Formation coals in the USA, from which oil is produced; New Zealand Tertiary coals; and Middle Jurassic coals from the Danish North Sea. It is likely that coals have at least contributed to significant oil discoveries in the Gippsland Basin, Australia; in the Turpan Basin, China; and in the Kutei and Ardjuna basins in Indonesia, but this remains unproven. Early reports that early Jurassic coals in mid-Norway were a major source of the reservoired oils have been shown to be inaccurate.None of the proposed ‘rules of thumb’ for generation or expulsion of petroleum from coals seem particularly robust. Decisions on whether a particular coal is likely to have been an active source for oil should consider all available geological and geochemical information. The assumptions made in computational models should be well understood as it is likely with new understandings of processes involved that some of these assumptions will be difficult to sustain.     

高密度电阻率法探测DNAPLs污染的适宜性探讨

重非水相流体（DNAPLs）的电阻率一般较高,在地下介质中与周围的地下水形成明显的电性差别。利用这一特性,非侵入式的高密度电阻率法（ERT）在探测DNAPLs污染场址中污染范围展现出一定优势。然而在实际场址的调查应用中,ERT有时无法探测到显著的高阻异常,或探测的高阻异常是由于介质的非均质性产生,从而导致对DNAPLs污染分布的误判。针对该问题,文章首先基于有效介质电阻率模型,计算了不同DNAPLs饱和度情形下的地层总电阻率值,从理论上解释了当DNAPLs污染程度较低时不存在显著高阻异常的原因。进一步构建理想ERT正演模型,探讨ERT探测DNAPLs污染的适宜性。研究结果表明:介质的非均质性（例如高阻的砾石等）对ERT探测具有很强的干扰,可造成DNAPLs分布范围的误判,因此传统静态ERT探测DNAPLs污染仅适用于均质介质或者非均质介质中DNAPLs污染程度较高的条件。对于非均质介质DNAPLs污染程度较低时,需采用基于时间域的差分反演方法屏蔽介质非均质性的影响,从而准确判定DNAPLs分布。     

A geometry-modelling method to estimate landslide volume from source area

Landslides - Knowledge of landslide volume is important to understand the extent of damages and evaluating methods of remediation. However, the volume of landslide is difficult to quantify due to...