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191.
场地污染土壤调查及评估探讨   总被引:4,自引:0,他引:4       下载免费PDF全文
提出场地土壤污染控制应从源头抓起,应控制搬迁企业移交土地后先拆迁平整,后进行土地利用性质变更的做法.在场地污染土壤调查中应重视对原址企业的历史沿革、平面布局、生产工艺等调查.指出多环境要素调查的重要性,以及调查过程要注意的事项.对土壤评估标准及引用的选择进行了探讨.  相似文献   
192.
概述了建设项目竣工环境保护验收监测点位的布设、监测因子的选择及监测频次的确定。  相似文献   
193.
垃圾堆放场释气源强确定与评价及其污染控制   总被引:6,自引:1,他引:5  
对北京北神树垃圾堆放场释气采样并定性定量分析,用上、下风测试和现场测试记录2种方法监测污染气体浓度,用改型扩散算出释气源强;通过室内模拟试验,找出产气量规律,产气成分所占比例,得出单位重量垃圾的产气量,进而推算出源强;评价垃圾释气对环境的影响并提出可行的控制污染对策。  相似文献   
194.
城市垃圾填埋场表面覆盖层的厚度及外观设计   总被引:4,自引:0,他引:4  
以青岛湖岛垃圾填埋场为试验点,研究了非封闭式填埋场的表面覆盖层的厚度,并对封闭式填埋场的表面覆盖层厚度和垃圾填埋场生态工程表面覆盖的外观设计进行了探讨。对于非封闭式填埋场,实验结果表明:表面覆盖层的厚度应在0.20~0.50m之间;对于封闭式填埋场,表面覆盖厚度应大于1.5m。垃圾填埋场的外观以坡度为1∶3的凸状设计较为适宜。   相似文献   
195.
为对智慧工地全生命周期的本质安全度进行分析与评价,综合运用本质安全理论,构建智慧工地本质安全度评价模型.首先,根据智慧工地本质安全定义,将智慧工地本质安全度划分为初始级、简单级、标准级、成熟级和卓越级5个等级;其次,基于智慧工地的生产现状,构建包括人员管理系统、机械设备管理系统、现场监测预警系统、过程控制管理系统等4个...  相似文献   
196.
为合理选择应急物流配送中心地址,提高应急管理能力,基于地震灾害风险评价数据,通过ArcGIS平台形成Voronoi图,可视化表达地震应急准备分区方案并进行应急物流中心预选址;在考虑需求权重情况下,构建应急物流配送中心优化选址模型,通过LINGO软件编程求解得出基于震灾应急准备分区的应急物流配送中心选址方案,并以A市为例,通过与传统行政区划建设方案进行对比,验证本文选址方案的有效性。研究结果表明:本文选址优化模型综合考虑各方面因素,使服务里程总量减少31.39%,单位服务量提高30.61%,验证选址方案的配送效率与公平性。  相似文献   
197.
To investigate the environmental safety of waste disposal landfill sites and of land reclaimed from such sites, we evaluated the toxicity of leachate from these sites by a combination of bioassays in the Japanese killifish medaka Oryzias latipes. We tested for lethal toxicity in adult and larval medaka and for hatching inhibition of embryos from eggs. As biochemical evidence of the effects of leachate exposure, CYP1A (EROD activity) and vitellogenin (Vtg) were induced. We also bioassayed water-treated leachate and downstream river water. Leachate solution was lethal to larval and adult medaka. Embryo hatchability was inhibited, and abnormal hatching, spinal deformity and anisophthalmia occurred in embryos exposed to leachate solution. CYP1A was induced by exposure to leachate solution diluted to 1.0%, and EROD activity was significantly higher than in control. Vtg and unknown proteins were induced in the sera of male medaka exposed to the diluted leachate solution. Conventional water treatments worked effectively to remove toxic compounds but did not work well to remove element ions, including heavy metals. Treated leachate produced neither lethal toxicity nor hatching abnormalities during the exposure period. Fish toxicity tests for leachate would be useful for monitoring the environmental safety of landfill sites.  相似文献   
198.
A forest health assessment was performed in stands dominated by bur oak and trembling aspen to study the potential effects of airborne emissions from a 132 MW coal-fired station. Forty-two stands were sampled within a 16-km radius of the station for both foliar stress symptoms and trace element toxicology. The concentrations of tracer elements (As, Ba, Sr, and V) in the leaf litter were not spatially congruent with airborne emission deposition models (except Ba, which showed elevated levels immediately SE of the station), nor were they at phytotoxic levels. Elemental concentrations were significantly related to soil parameters including organic matter and texture. No patterns were found in forest health along directional or distance gradients from the generating station. Trembling aspen stands demonstrated little decline in general, but three of the 19 bur oak plots, all located on thin sandy soils developed on calcareous till, demonstrated branch dieback. In addition to poor soil conditions, two of these sites also had high water tables, and exhibited tree mortality. The bur oak decline did not appear to be related to emissions from the station, but is suspected to be a result of poor site quality, with urban development as a confounding factor.  相似文献   
199.
Key attributes of the source zone and the expanding dissolved plume at a trichloroethene (TCE) site in Australia were evaluated using trends in groundwater monitoring data along with data from on-line volatile organic compound (VOC) samplers and passive flux meters (PFMs) deployed in selected wells. These data indicate that: (1) residual TCE source mass in the saturated zone, estimated using two innovative techniques, is small ( 10 kg), which is also reflected in small source mass discharge ( 3 g/day); (2) the plume is disconnecting, based on TCE concentration contours and TCE fluxes in wells along a longitudinal transect; (3) there is minimal biodegradation, based on TCE mass discharge of  6 g/day at a plume control plane  175 m from source, which is also consistent with aerobic geochemical conditions observed in the plume; and (4) residual TCE in the vadose zone provides episodic inputs of TCE mass to the plume during infiltration/recharge events. TCE flux data also suggest that the small residual TCE source mass is present in the low-permeability zones, thus making source treatment difficult. Our analysis, based on a synthesis of the archived data and new data, suggests that source treatment is unwarranted, and that containment of the large TCE plume ( 1.2 km long,  0.3 km wide; 17 m deep;  2000–2500 kg TCE mass) or institutional controls, along with a long-term flux monitoring program, might be necessary. The flux-based site management approach outlined in this paper provides a novel way of looking beyond the complexities of groundwater contamination in heterogeneous domains, to make intelligent and informed site decisions based on strategic measurement of the appropriate metrics.  相似文献   
200.
借助Wolf的土层和半空间精确动力刚度矩阵及斜线荷载的格林函数,利用间接边界元法在频域内求解了局部断层场地对SV波的散射,着重分析了破碎带较窄断层两侧围岩动力响应的基本规律,以及场地动力特性对散射的影响.研究表明,破碎带断层对SV波有显著的影响,即使破碎带很窄,也可以对SV波产生很大的放大作用;层状场地的动力特性对放大作用有显著的影响.  相似文献   
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