Assessment of groundwater quality using multivariate statistical techniques in the Azmak Spring Zone,Mugla, Turkey

About 150 coastal spring outlets discharging from a karstified carbonate rock aquifer constitute the Azmak streamflow which is slightly brackish with 3000 mg/l of total dissolved solids. In this study, multivariate statistical methods were applied including the use of factor analysis, correlation analysis and cluster analysis to evaluate groundwater quality of Azmak Spring Zone using eight variables (Ca, Mg, Na, K, Cl, SO₄, EC₂₅ and B) at 19 water points sampled in the dry and wet seasons. Hydrochemical analysis results revealed that for majority of the sampling points, the abundance of cations and anions were ordered as Na?+?K?>?Mg?>?Ca and Cl?>?SO₄?>?HCO₃?+?CO₃, respectively. Factor analysis results indicated that three factors explain 98% and 91% of the total variance in the dry and wet seasons, respectively. Factor 1 was found to be associated with the seawater, factor 2 indicated the effect of fresh water and factor 3 was defined to reflect the effect of seasonal fresh surface water contribution. Cluster analysis results indicated that two main groups and four subgroups could be defined with respect to the ratio of the seawater contribution. Cluster A (A1 and A2) represents the waters affected by seawater while waters less affected by the seawater intrusion are grouped in cluster B (B1 and B2).     

Assessment of soil and water contamination around an ash-disposal site: a case study from the Seyitömer coal-fired power plant in western Turkey

Seyitömer power plant comprises 4.8% of Turkey's total energy production. The fly ash produced has been deposited in the area, since the 1960s, by a dry disposal technique. In 1997, wet disposal was improperly exercised in the area causing ash flow over agricultural fields. This study is concerned with the chemical analysis of ash, soil and water samples collected in the area following ash-removal studies after the ash flow in 1997. The results reveal that Na, K, Ca, Mg, Mn, Al, Fe, Co, and Cr contents of soil and water are governed by basement lithology in the area, whereas Cd, Pb, Zn, and Cu contents are determined by fly ash from disposal sites. Although lithogenic Cr and Co contents are exceedingly high, comparison with the regulatory standards for drinking water, irrigation water and agricultural soils reveals no pollution pertinent to solid waste production in waters, whereas there is moderate pollution by Pb and Cu in soils.     

Performance Prediction of Large-Diameter Circular Saws Based on Surface Hardness Tests for Mugla (Turkey) Marbles

Surface hardness tests such as Shore hardness (SH) and Schmidt hammer rebound hardness (SR) may provide a quick and inexpensive measure of rock hardness, which may be widely used for estimating the mechanical properties of rock material such as strength, sawability, drillability and cuttability. In the marble industry, circular sawing with diamond sawblades constitutes a major cost in the processing. Therefore, several models based on the relations between hourly slab production (P _hs), rock surface hardness (SH and SR) and mineral grain size (S _cr) were developed using the data obtained from field and laboratory measurements on five different marbles quarried in the Mugla Province of Turkey. The models which include surface hardness and crystal size may as well be used for the prediction of sawability (hourly slab production) of carbonate rocks using large-diameter circular saws.     

Concentrations and distribution of elements in milled-coal, power plant ashes and stack-emitted materials in a Western Canadian coal-fired power plant

The focus of this study is to determine the concentrations and the distributions of elements of prime environmental concern （As, Cd, Cr, Cu Hg, Mo, Ni, Pb, Se and V） and other elements of environmental interest （B, Ba, Be, Co, Mn, U） in milled coals, power plant ashes, and stack-emitted materials from a Western Canadian power plant using bituminous coal. The concentrations of elements were determined using neutron activation analysis （NAA）, Inductively Coupled Plasma Emission Spectroscopy （ICPES）, and Inductively Coupled Plasma-Mass spectroscopy （ICP-MS） for most elements, Graphite Furnace Atomic Absorption （GFAA） for Pb, and Cold Vapor Atomic Absorption （CVAA） for Hg. The result of the study shows that the total rate of input is 423.5 kg/d for elements of prime environmental concern and 280 kg/d for elements of environmental interest. The concentrations of most elements in milled coal are low as compared to world coals and other Canadian milled coals. The total output of these two groups of elements is 2.9 kg/d and 110.4 kg/d, respectively. This indicates that only a small amount of the total input elements from the milled coal is emitted. Most of it is captured by the bottom and ESP ashes with the exception of the highly volatile As Hg, F, Br, and Cl. The element with highest rate of emission for elements of prime environmental concern is Se （0.73 kg/d） and B （95 kg/d） for the elements of some environmental interest.     

Coal geology and coal quality of the Miocene Mugla basin, southwestern Anatolia, Turkey

This work focuses on the relationship between the coal geology and coal quality of the Miocene Mugla basin, Southwestern Anatolia, Turkey. To this end, detailed petrographical, mineralogical and geochemical studies were performed on composite profile samples from the nine coal fields in the Mugla basin (Alatepe, Bagyaka, Bayir, Çakiralan, Ekizköy, Eskihisar, Hüsamlar, Sekköy and Tinaz coal fields). The Mugla lignite is a high ash (from 16 to 56%) and sulphur (from 2.1 to 5.7%) lignite which is petrographically characterised by a high huminite content, mainly gelinite macerals. The mineral matter of the studied lignite samples is made up mainly of clay minerals and quartz, with the exception of the Sekköy and Ekizköy lignites, in which calcite is the dominant mineral phase with minor amounts of quartz, clay minerals, pyrite and gypsum and traces of aragonite. Syngenetic opal is also frequently identified in these samples. The differentiation of these two types of lignite with specific mineralogical patterns is attributed to the contemporaneous development of peatlands with a high detrital input, dominated by the quartz and clay mineral setting, and peatlands with low detrital supply and a dominant carbonate-rich lacustrine environment. The higher water table of the latter allowed the precipitation of micritic carbonates and the development of lakes with abundant mollusc fauna. This differentiation is also evidenced by the geochemical data. Thus, the Sekköy, Ekizköy, Hüsamlar, Bayir and Alatepe lignites are characterised by relatively low Al and Fe contents (<1.4%) and high sulphur contents (4.2 to 5.7%). In addition Sekköy and Ekizköy show relatively high contents of Ca (6.3–7.1% compared to 1.6–3.8% in the other lignites). All the lignite samples studied are characterised by relatively high Mo and U contents when compared with the worldwide averages of trace elements in coal. Relatively high alkaline syngenetic conditions of the peat-forming environment of the Mugla coal are deduced from the following mineralogical, petrographical and geochemical evidence: (a) the precipitation of syngenetic opal (dissolution of quartz and re-precipitation as opal) and calcite; (b) minor and very early syngenetic sulphide precipitation (only framboidal and euhedral pyrite); (c) high bacterial activity, typical of high pH conditions, inferred from low preservation of tissue structures; (d) preservation of aragonite gastropod shells; and (e) the anomalous enrichment of U, Mo and W. A key result of the study of Mugla limnic coals (at least of the Sekköy and Ekizköy coal fields) is that a major influence was exerted on the early diagenetic evolution of the coal by the hydrochemistry of the lacustrine waters. This hydrochemistry was largely linked to the lithology of the surrounding source rock areas although the final evolutionary trend of the solute composition in the lake waters, characterized by very high carbonate and sulphate contents, was largely enhanced by the endorheic river drainage system and the arid–semiarid paleoclimatic situation under which organic matter accumulation took place.     

宝鸡燃煤电厂周围土壤天然放射性核素的空间分布特征

测定了燃煤电厂周围土壤环境中天然放射性核素226Ra、232Th和40K的比活度,用地统计学方法分析了电厂周围土壤中226Ra、232Th和40K的空间分布特征,并进行了风险性评价.结果表明,226Ra和232Th比活度表现出比较明显的条带状空间分布特征,40K则没有明显的方向性效应;风险性评价结果同样表现出了方向性效应.研究结果可为放射性污染防治和管理决策等提供参考依据.     

The fate of trace elements in a large coal-fired power plant

 A quick approach is proposed to evaluate the environmental fate of trace elements in coal-fired power plants. It is based on the analysis of feed coal and solid combustion by-products, together with the leachates of the latter. The application of this method in a 1050 MW power plant from NE Spain shows that: (1) Ba, Ce, Co, Cs, Cu, Dy, Ga, Ge, La, Lu, Mn, Ni, Rb, Sr, Tb, Th, Y, Yb, Zn and Zr were retained in the solid wastes; (2) As, B, Be, Cd, Cr, Li, Mo, Pb, Sb, Sn, Ta, Tl, U, V and W were only partially retained in the solid wastes; and (3) Hg and Se were primarily emitted to the atmosphere. Received: 2 February 2000 · Accepted: 18 May 2000     

Environmental assessment of elements and polyaromatic hydrocarbons emitted from a Canadian coal-fired power plant

A detailed assessment of elements was carried out at a power plant rated at approximately 760 MW of electricity using western Canadian subbituminous coal. The concentrations of elements of environmental concern (As, Cd, Cr, Hg, Ni, and Pb) in milled coals, ashes, stack-emitted materials. Speciation of As, Cr, and Ni were determined. The polyaromatic hydrocarbons (PAHs) emitted from the stack were also measured. The rates of input of elemental input for As, Cd, Cr, Hg, Ni, and Pb were 28, 0.94, 230, 0.44, 44, and 88 kg/day, respectively; of which only 0.16, 0.01, 0.40, 0.27, 0.15, and 0.04 kg/day, respectively, were stack emitted. The total stack emission of toxic elements is 1.02 kg/day, with Cr being the highest contributor to this group with 0.4 kg/day. However, Hg at 0.27 kg/day has the highest percentage rate of emission at about 60%, while Cd has the lowest at about 1%. The electrostatic precipitator (ESP) removes a significant portion of the elements indicated by their relative enrichment (RE) ratios greater than 0.7. The results show that most of the elements in milled coal are low compared to world coals and other Canadian milled coals.Mercury is mostly ( 81%) emitted as gaseous elemental mercury (GEM), with 19% as reactive gaseous mercury (RGM). Particulate mercury is very low and averages about 0.1% of the total mercury at this station. Most of the arsenic in the milled coal is primarily associated with pyrite or as arsenate in its less toxic form of As⁺⁵ (> 95%). In both bottom and fly ashes, more than 95% of the total arsenic is present as As⁺⁵. Chromium in the milled coal and bottom ash is mostly non-toxic (Cr⁺³). The more toxic Cr⁺⁶ comprise less than 5% of the total Cr in the ESP fly ash and the stack-emitted ash. Nickel in milled coal and ashes is in the form of non-toxic Ni⁺², predominantly in coordination with oxygen.The emitted PAHs include acenapthene, fluorene, 2-methyl-fluorene, phenathrene, anthracene, fluoanthene, and pyrene; which are emitted from stack at the combined rate of 3.6 g/day. The concentrations of elements of environmental concern (As, Cd, Hg, Ni, and Pb) emitted to the atmosphere by the power plant in the zone of maximum impact at ground level are lower than those listed in the Health Guidelines of the USEPA and Canadian National Air Pollution Surveillance. This is based on stable meteorological conditions, down wind from the power plant for a maximum distance of 3 km.     

燃煤排放可吸入颗粒物的显微结构与物质组成研究

对我国西南地区三个火电厂排放的可吸入颗粒物(PM10)的显微结构、矿物和化学组成等的研究表明,在PM10中,随着粒径的减小,非球形颗粒的比例增加;同原状飞灰相比,PM10以实心结构为主,多孔和空心结构较少;场发射扫描电子显微镜下,多数PM10颗粒的表面并不光滑,而是布满了次级微细颗粒;PM10的物相组成与燃煤煤种密切相关,小龙潭电厂PM10主要矿物包括石英、石灰、石膏和赤铁矿,而贵阳电厂PM10则以莫来石和石英为主;据单个PM10颗粒化学组成,将PM10分为硅质、铁质、Ca-铝硅质、Fe-铝硅质、Ca-Fe-铝硅质和硫酸钙六种颗粒类型;从不同采样点PM10元素组成看,从静电除尘器(ESP)前到ESP,PM10化学成分变化不大,到ESP后,元素Fe、Ca、Mg和Al的含量急剧减少,而Na的含量则迅速增高.     

Mineralogy and geochemistry of feed coals and their combustion residues from the Cayirhan power plant,Ankara, Turkey

A total of 48 samples, feed (run-of-mine) coals and their combustion residues (fly ash and bottom ash) were systematically collected twice a week over a 4 week period (June 1998) from two boiler units (I and II) of the Cayirhan power plant (630 MW) that burns zeolite-bearing coals of late Miocene age. The feed coals are high in moisture (22.8% as-received) content and ash (44.9%) yield and total S content (5.1%), and low in calorific value (2995 kcal/kg). The mineralogy of the feed coals contains unusually high contents of the zeolites (clinoptilolite/heulandite and analcime), which are distributed within the organic matter of coal. Other minerals determined are gypsum, quartz, feldspar, pyrite, dolomite, calcite, cristobalite and clays. Common minerals in the crystalline phase of the combustion residues are anhydrite, feldspar, quartz, hematite, lime and Ca–Mg silicate. Minor and trace amounts of magnetite, cristobalite, maghemite, gehlenite, calcite and clinoptilolite/heulandite are also present in the combustion residues. Trace element contents of the feed coals, except for W, fall within the estimated range of values for most world coals; however, the mean values of Mn, Ta, Th, U and Zr are near maximum values of most world coals. Elements such as As, Bi, Ge, Mo, Pb, Tl, W and Zn are enriched more in the fly ash compared to the bottom ash.     

Assessment of elemental content of milled coal,combustion residues,and stack emitted materials: Possible environmental effects for a Canadian pulverized coal-fired power plant

Two monitoring studies were carried out at four-year intervals on a power plant that uses western Canadian subbituminous coal and generates approximately 800 Mw/h of electricity. The distributions of elements of environment concern (As, Hg, Ni, Pb, and Cd) and elements of environmental interest (B, Ba, Be, Cl, Co, Cr, Cu, Mn, Mo, Th, Se, V, U, and Zn) in milled coals, power plant ashes, and emitted materials from the stack were determined using neutron activation analysis (NAA), Inductively Coupled Plasma Emission Spectroscopy (ICPES), and Inductively Coupled Plasma-Mass spectroscopy (ICP-MS) for most elements, Graphite Furnace Atomic Absorption (GFAA) for Pb, and Cold Vapor Atomic Absorption (CVAA) for Hg.The concentrations of most of elements in milled coal are low as compared to world coals and other Canadian milled coals. For example, in both studies mercury is within the lower range of world coal. Bottom ashes from both studies have low concentrations of As, Cd, Hg, Pb, and Zn, as well as low relative enrichment factors (RE) for the same elements, indicating that they were not enriched in the bottom ash. The ESP's remove most of the elements of environmental interest as indicated by their high RE ratios of greater than > 0.7.The rates of input of elements of environmental concern (As, Cd, Hg, Pb and Ni) for this station were 23.65, 1.24, 0.54, 98.2 and 95.2 kg/day, respectively, of which only 0.20, 0.02, 0.31, 0.48 and 0.36 kg/day were emitted from the stack. Thus only a small amount of these elements found in the milled coal was emitted while most were captured in the bottom and the ESP ashes. Nickel has the highest rate of emission (0.48 kg/day) within the elements of environmental concern group. However, the Ni emitted from this station does not belong to the toxic species. The element with the lowest rate of emission is Cd (0.02 kg/day). The total emission of elements of environmental concern is 1.37 kg/day, which is low as compared their ambient concentrations in either rural or urban air. The total rate of emission of B, Ba, Be, Co, Cr, Cu, Mn, Mo, Se, Th, U, V, and Zn is 56.51 kg/day and is mostly comprised of the total emission of Ba (21.73 kg/day) and Zn (19.14 kg/day).     

超低排放燃煤电厂一次颗粒物和黑碳实时排放特征

燃煤电厂是大气一次污染物的重要排放源,其超低排放改造改变了大气颗粒物排放特征。为满足当前高时间分辨率排放清单构建的需要,燃煤电厂颗粒物实时排放质量浓度及关键组分比值亟需更新。本研究基于稀释通道采样系统,对某超低排放改造后的燃煤电厂开展实测,获得该燃煤电厂可吸入颗粒物(PM₁₀)、细颗粒物(PM_2.5)、超细颗粒物(PM_1.0)和黑碳(BC)的实时排放质量浓度,更新各污染物排放因子,分析PM_1.0/PM_2.5、PM_2.5/PM₁₀和BC/PM_2.5质量浓度比值(文中以上比值均为质量浓度比值)日变化。结果表明,上述污染物排放平均质量浓度分别为(5.0±6.0) mg/m³、(5.0±5.9) mg/m³、(4.9±5.9) mg/m³和(36.6±28.3)μg/m³;对应的排放因子分别为0.03 kg/t、0.03 kg/t、0...     

Investigating chemical and microbiological contaminants in drinking water of Cankiri Province, Turkey

Providing clean and good quality water is essential for sustaining human health and life, and for ensuring the preservation of ecosystems. The purpose of this paper is to identify the chemical and microbiological characteristics of drinking water source of Cankiri City (as raw and purified) and tap water samples of central Cankiri and its towns. The water quality in Cankiri Province was evaluated by comparing these parameters with permissible limits set by Turkish legislation and World Health Organization (WHO). Raw and purified water samples were analyzed for chemical and microbiological qualities, trace metal, pesticide, polycyclic aromatic hydrocarbon (PAH), trihalomethane (THM), and benzene contents. These analyses indicated that the parameters exceeded those of the Turkish legislation (phenolic substance, biochemical O₂ demand, Mn, Se, fecal coliform) and the WHO guidelines (pH, phenolic substance, Cd, Se, fecal coliform). In this study, tap water samples were also collected from 50 sampling sites from central Cankiri and its towns during 2010. In these samples, chemical characteristics (bromide, free chlorine, nitrate and nitrite), carbamate, herbicide and fungicide contents, and microbiological contaminants were investigated. In the tap water samples, it was found that free chlorine concentrations exceeded the Turkish guidelines. Escherichia coli, total coliform and enterococci were used as indicators of possible sewage contamination due to inappropriate water distribution. Our results also indicated that significant microbiological contaminations in the tap water samples were above the guidelines for drinking water given by the Turkish legislation and WHO, and might pose a health risk. This investigation of drinking water samples of the Cankiri Province would point to the need of a new drinking water treatment strategy to ensure the safety of consumers.     

Spatial analysis and hazard assessment of mercury in soil around the coal-fired power plant: a case study from the city of Baoji, China

Based on systematic sampling of soil around the coal-fired power plant (CFPP), the content of Hg was determined, using atomic fluorescence spectrometry. The result shows that the content of Hg in soil is different horizontally and vertically, ranges from 0.137 to 2.105 mg/kg (the average value is 0.606 mg/kg) and is more than the average content of Hg in Shaanxi, Chinese and world soil. In this study, spatial distribution and hazard assessment of mercury in soils around a CFPP were investigated using statistics, geostatistics and geographic information system (GIS) techniques. Ordinary kriging was carried out to map the spatial patterns of mercury and disjunctive kriging was used to quantify the probability of the Hg concentration higher than the threshold. The maps show that the spatial variability of the Hg concentration in soils was apparent. These results of this study could provide valuable information for risk assessment of environmental Hg pollution and decision support. An erratum to this article can be found at     

Assessment of geo-environmental problems of the Zonguldak province (NW Turkey)

The Zonguldak province is a coastal settlement area that has been suffering from serious natural and human-induced environmental problems sourced by its geology and geomorphology. Since the province locates at the heart of a coal-producing basin, the geo-environmental problems related to mining activities such as esthetic degradation, disposal of mining wastes and subsidence of the abandoned coal galleries are badly affecting every day life in Zonguldak province. Disposal of municipal wastes is also a big problem since only one municipality out of 32 has a sanitary disposal area. The rest of the municipalities dispose their solid wastes to rivers or to the sea. The province has also some health problems, which are pointed out in the literature, related to coal mining and geologic environment. These are cytogenetic damage in peripheral lymphocytes and pheumoconiosis (most commonly seen at coal workers), goiter and cancer. Landslides are the most important hazards in the area since 13% of the total surface of the Zonguldak is affected by landslides. In this study, considering the hazard potential special attention is given to deep landslides and using the stepwise forward conditional logistic regression technique, the landslide susceptibility map for the Zonguldak province is produced. The results showed that the most important independent variables governing the landslides are slope gradient, volcanic, and sedimentary rocks of Eocene and clastic and carbonate units of Cretaceous. The landslide map is used as a base map for the production of geo-hazard reconnaissance map on which areas subjected to other important geo-hazards (flood, earthquake and subsidence) are also shown to provide guidance for both existing settlement areas to take the necessary preventive measures and for new developing settlement areas to avoid the problematic areas.     

An integrated analysis of air pollution from US coal-fired power plants

The United States is one of the world's leaders in electricity production, generating about 4116 billion kWh in 2021, of which coal accounted for 21.8% of the total. This study applies an integrated approach using both terrestrial and satellite data to specifically examine emissions from coal-fired power plants and its spatial extent. The study also highlights the effectiveness of government policies to reduce emissions. It was found that emission of pollutants from the country's energy sector has been steadily declining, with annual emissions of sulfur dioxide (SO₂) and nitrogen oxides (NO_x) decreasing from the US electric power sector between 1990 and 2020 by 93.4% and 84.8%, respectively, and carbon dioxide (CO₂) by 37% between 2007 and 2020. Although overall emissions from coal-fired power plants are declining, some individual plants have yet to install environmental equipment to control emissions. According to US government data, major emitters of SO₂, NO_x, and CO₂ in the US are the Martin Lake power plant in East Texas, the Labadie power plant near St. Louis, Missouri, and the James H Miller Jr plant near Birmingham, Alabama. This study also integrates TROPOMI satellite data to detect point emissions from individual power plants. While the highest levels of measured pollutants were over the country's major cities and areas of fossil fuel extraction, TROPOMI could clearly distinguish the pollution caused by power plants in more rural areas. Although the US has made great strides in reducing emissions from coal-fired power plants, these plants still represent a major source of pollution and remain a major concern. Totally eliminating coal as a power source will be difficult with the higher power demands resulting from the transition to electric automobiles.     

An assessment of soil contamination due to heavy metals around a coal-fired thermal power plant in India

Combustion of coals in thermal power plants is one of the major sources of environmental pollution due to generation of huge amounts of ashes, which are disposed off in large ponds in the vicinity of the thermal power plants. This problem is of particular significance in India, which utilizes coals of very high ash content (∼55 wt%). Since the thermal power plants and the ash ponds are located in densely populated areas, there is potential chance for contamination of soil and groundwater of the surrounding areas from the toxic trace elements in the ash. An attempt has been made to study the extent of soil contamination around one of the largest thermal power plants of India located at Kolaghat, West Bengal India. Chemical analysis of the top soils and the soils collected from the different depth profiles surrounding the ash ponds, show that the top soils are enriched in the trace elements Mo, As, Cr, Mn, Cu, Ni, Co, Pb, Be, V, Zn, which show maximum enrichment (2–5) in the top soils collected from all the soil profiles. These elements are also enriched in the pond ash. Since there are no other sources of industrial effluents, it can be said that the enrichment of the trace elements (Mn, Co, Mo, Cr, Cu, Pb, Zn, As, Ni, Be, V) is attributed to their input from ash from the disposal pond. The study has been further strengthened by log-normal distribution pattern of the elements.     

Effectiveness of wind-blown sands on treatment of wastewater from coal-fired power plants

Untreated disposal of wastewater from coal-fired power plants has environmental and public health concerns in the developing Shanbei Energy Base, Northwest China. An in situ experiment was conducted in the easily accessible wind-blown sands to study their efficiency in removal of pollutants. Approximately 245 l of wastewater was used in the test, which lasted 409 min. Sand samples were collected at 5 discrete depths, 0.2, 0.4, 0.6, 1, and 1.5 m from the surface before, at the end of, and 20 days after the infiltration test. Pollutants commonly found in wastewater were analyzed for all the sand samples. 20 days after infiltration, the content of As in the sand samples had a general reduction, decreased from original 0.0109–0.0132 to 0.005 mg/kg. The content of N-NH₄ also decreased from original 1.1–1.5 to 0.8–1.0 mg/kg. But the content of Cd and petroleum was stable and had no decreasing trend. The test indicates the wind-blown sands are more effective for As and N-NH₄, but less effective for petroleum and Cd.     

Strontium isotopes as tracers of airborne fly ash from coal-fired power plants

Fly ash generated by coal-fired power plants is in part collected by filters in the emission stacks while a small portion is vented into the atmosphere. Since many of the coalfired power plants in the western United States are located in the desnrt, the ability to monitor fly ash emissions requires a chemical tracer that utilizes desert soil and plant interactions with the fly ash deposited in the desert environment. This investigation presents the results of a controlled greenhouse experiment in which a native desert plant, the brittlebush (Encelia farinosa), was grown on admixtures of desert soils and fly ash. The fly ash is strongly enriched in Sr and the brittlebush is a Sr accumulator. The data demonstrate that (1) the brittlebush isotopically equilibrates with desert soils whose fly ash components are as low as 0.25% by weight, (2) the fly ash Sr is apparently more available to the plant, than Sr derived from the soils, and (3) the difference between the⁸⁷Sr/⁸⁶Sr ratio of the fly ash (0.70807) and soils (0.71097 to 0.71117) warrants further investigations in the natural environment to determine the practicality of this method as a natural tracer of fly ash in the environment.