石油化工场地环境评价

介绍了石油化工场地环境评价的程序和方法,内容主要包括石油化工场地环境评价的基本内容、土壤和地下水监测点位的布设、样品的采集与保存、样品的预处理及分析、质量控制等.     

Effect of natural organic matter on arsenic release from soils and sediments into groundwater

Arsenic (As) contamination in groundwater has received significant attention recently. Natural and anthropogenic sources contribute to the worldwide occurrence of As contamination. As speciation is an important factor related to its toxic and mobile behavior. The release of As from soils and sediments into groundwater is governed by several geophysicochemical processes, of which, As sorption behavior is of principle significance. This review paper summarizes existing information regarding the effects of natural organic matter (NOM) on the fate and mobility of As species in the environment. NOM may enhance the release of As from soils and sediments into the soil solution, thereby facilitating As leaching into the groundwater. The main influencing mechanisms include competition for available adsorption sites, formation of aqueous complexes, and/or changes in the redox potential of site surfaces and As redox speciation. NOM may also serve as binding agents, thereby reducing As mobility. However, comparably little research has been performed on this aspect. Since most investigations have been done on purified minerals under laboratory conditions, further research involving various geological materials under natural environmental conditions is required. Development of proper geochemical conceptual models may provide means of predicting the role of NOM in arsenic leaching and/or immobilization.     

成品油管道地下水环境风险评价研究

应用环境风险评价理论,以石家庄-太原成品油管道为例,通过对工程与环境特性进行分析,识别出其主要的地下水环境风险。根据FEMWATER模型软件,结合当地的水文地质条件,模拟在设定的假想事故状态下,对地下水环境风险进行了评价研究。并提出了有针对性的工程防范措施和监测、管理对策,为工程建设环境风险管理和水资源保护提供了参考依据,也为其他成品油管道的环境风险评价提供了参考。     

基于组合权物元分析模型的地下水水质评价

针对以往地下水水质评价中多采用单一权重法确定各评价指标权重的不足,提出基于主客观组合权重的权重计算模式,并运用权重风险度计算公式选出相对合适的组合权重,再与物元分析理念相结合,构建用于评价地下水水质的组合权物元分析模型。应用该模型对阜新新邱露天煤矿排土场淋溶水的地下水污染区的12个监测点水质进行综合评价。结果表明:研究区的1#～5#监测点水质均达到Ⅱ级以上,符合国家饮用水标准要求;6#～12#监测点水质均受到不同程度的污染,已不能饮用。评价结论与灰色关联分析法和模糊综合评价法所得结论基本一致。     

Temporal trends in agricultural water use and the relationships to hydroclimatic factors in the High Plains aquifer region

The High Plains aquifer (HPA) is the primary water source for agricultural irrigation in the US Great Plains. The water levels in many locations of the aquifer have declined steadily over the past several decades because the rate of water withdrawals exceeds recharge, which has been a serious concern to the water resources management in the region. We evaluated temporal trends and variations in agricultural water use and hydroclimatic variables including precipitation, air temperature, reference evapotranspiration, runoff, groundwater level, and terrestrial water storage across the HPA region for different periods from 1985 to 2020 at the grid, county, or region scale. The results showed that water withdrawals decreased from 21.3 km³/year in 1985 to 18.2 km³/year in 2015, while irrigated croplands increased from 71,928 km² in 1985 to 78,464 km² in 2015 in the entire HPA. The hydroclimatic time-series showed wetting trends in most of the northern HPA, but drying and warming trends in the southern region from 1985 to 2020. The groundwater level time-series indicated flat trends in the north, but significant declining in the central and southern HPA. Trends in irrigation water withdrawals and irrigation area across the HPA were controlled by the advancement of irrigation systems and technologies and the management of sustainable water use, but also were affected by dynamical changes in the hydroclimatic conditions.     

成都平原蔬菜生产中灌溉水对农药渗漏的影响研究

针对成都平原蔬菜生产中大量施用农药、大量灌水的特点,首次在国内应用欧洲官方成熟的农药评估模型——PEARL模型,研究评估了成都平原当前蔬菜生产中的灌溉方式对两种不同特性农药的渗漏的影响。杀毒矾(土壤吸附力(KOM)为0 L/kg,半衰期(DT50)为80 d)在没有灌溉条件下,其渗出土体时的最大质量浓度是190μg.L-1,而有灌溉条件下其渗出质量浓度则可达523μg.L-1,是没有灌溉条件下的2.75倍。三唑磷(KOM为200 L.kg-1,DT50为60 d)在没有灌溉条件下,其渗出土体时的最大质量浓度是0.025μg.L-1,而有灌溉条件下其渗出质量浓度为0.13μg.L-1,比没有灌溉时提高了4.2倍。不管有没有灌溉三唑磷在该地区对地下水的污染风险都很小,而杀毒矾的风险则很高。因此,农药的化学特性是影响农药渗漏的最重要的因子。在蔬菜生产中应尽量选用被土壤吸附力强、半衰期短的农药,例如:三唑磷;农药在土壤中的移动载体是土壤水,不合理的灌溉会大大地加大农药淋溶,应当多使用微喷、滴灌等节水灌溉措施,减少使用漫灌等耗水多的原始灌溉方式。     

Arsenic in groundwaters of the Lower Mekong

Increasing incidence and awareness of arsenic in many alluvial aquifers of South-east Asia has raised concern over possible arsenic in the Lower Mekong Basin. Here, we have undertaken new research and reviewed many previous small-scale studies to provide a comprehensive overview of the status of arsenic in aquifers of Cambodia and the Cuu Long Delta of Vietnam. In general natural arsenic originates from the Upper Mekong basin, rather than from the local geology, and is widespread in soils at typical concentrations of between 8 and 16 ppm; (dry weight). Industrial and agricultural arsenic is localised and relatively unimportant compared to the natural alluvial arsenic. Aquifers most typically contain groundwaters of no more than 10 μg L⁻¹, although scattered anomalous areas of 10 to 30 μg L⁻¹ are also quite common. The most serious, but possibly ephemeral arsenic anomalies, of up to 600 μg L⁻¹, are associated with iron and organic-rich flood-plain sediments subject to very large flood-related fluctuations in water level, resulting in transient arsenopyrite dissolution under oxidizing conditions. In general, however, high-arsenic groundwaters result from the competing interaction between sorption and dissolution processes, in which arsenic is only released under reducing and slightly alkaline conditions. High arsenic groundwaters are found both in shallow water-tables, and in deeper aquifers of between 100 and 120 m depth. There is no evidence of widespread arsenicosis, but there are serious localised health-hazards, and some risk of low-level arsenic ingestion through indirect pathways, such as through contaminated rice and aquaculture. An almost ubiquitous presence of arsenic in soils, together with the likelihood of greatly increased groundwater extraction in the future, will require continuing caution in water resources development throughout the region.     

Hydrogeology of a restored coastal dune system in northeastern Scotland

This paper reports the results of 12 years of hydrological monitoring at the St. Fergus dune system in northeastern Scotland. The site is adjacent to the UK’s largest gas terminal and the dunes are crossed in five places by North Sea gas pipelines which were constructed between 1976 and 1990. These are buried beneath the dune system which was restored after pipeline installation. The dunes include a substantial freshwater wetland which is seasonally flooded and provides an important habitat for waterfowl. The hydrogeology of the site is characterized and the hydrogeological processes that sustain this wetland feature are considered including recent climatic fluctuations. Nomenclature: Names of vascular plants follow Clapham et al. (1962).     

Acidification of groundwater in water-filled gravel pits -- a new environmental and geomedical threat

Swimmers and users of motor boats frequenting old, water-filled gravel pits in Kiiminki, Northern Finland, found in August 1993 that they were suffering from painful irritation of the eyes and that their boats had developed a finely polished surface on their aluminium hulls, evidently due to the corrosive action of the water. Subsequent measurements carried out by the water authority showed that the pH of the water in some of the pits was extremely low, reaching a value of 3.4 at its lowest. To find out the causes of the abnormally low pH values, the present authors began systematic measurements of the pH and determination of the chemical composition (Si, Al, Ca, Mg, K, Na, Fe, Mn, Cu, Pb, Ni, Cd, Cl^-, NO₃ ^-, SO₄ ^2-) of the water in 23 gravel pits. In addition, a series of laboratory experiments was carried out to examine the interaction of water with samples of the soil and bedrock of the area to evaluate the role of this process as a possible cause of the acidification. The results show that the reaction of water with the moderately to intensively weathered sulphide and jarosite-bearing black schists, typical of the bedrock of the area, can bring about aqueous solutions similar in pH and sulphate--nitrate ratios to those found naturally in the gravel pits. The contribution of other possible mechanisms, e.g. acidic precipitation as such or combined with enhanced evaporation, the possible use of the pits as dumping sites for acidic waste or the flow or seepage of acidic peat-bog waters into the pits from the surrounding wetlands, cannot be ruled out entirely, but their contribution seems to be of minor importance. Since the concentrations of several heavy metals (notably Pb, Cd, Ni, Fe and Mn) and of sulphate and aluminium has increased in the pit water as a result of the acidification process and exceed the norms laid down in the EU Drinking Water Directive, acidification of water in gravel pits due to the oxidation of sulphides must be regarded as a new, serious environmental and geomedical threat which has so far remained poorly known or unrecognised.     

运用SCI-GROW模型预测农药对地下水的污染风险

在对美国环境保护局开发的地下水暴露评价模型进行比较的基础上,选择SCI-GROW模型预测我国福建省甘蔗种植区5种常用农药对地下水的污染风险,并将模型预测结果与该地区地下水中农药的实测结果进行比较,对模型进行验证.结果表明,模型预测结果与实测结果之间具有很好的相关性,SCI-GROW模型能较好地用于我国东南沿海等地下水位较高、降水量较大、土壤砂性等地下水易受污染地区农药的筛选评价.最后,运用SCI-GROW模型预测涕灭威等17种我国常用农药对地下水的污染风险,为这些农药的科学使用提供参考.