环境同位素和水化学在堤坝渗漏研究中的应用

首先分析了环境同位素和水化学在堤坝渗漏分析研究中的基本原理，作为天然示踪剂，环境同位素和水化学标记着地下水、河水和降水。通过对比地下水与河水、雨水的同位素和化学成分，确定这几类水之间的水力联系，从而判别地下水的补给源、渗漏区的位置与范围、地层的性质等。在3个实例中，运用环境同位素和水化学得出了许多有益的结论，并且这些结论也通过其它方法得到了验证。在堤坝的渗漏研究中，环境同位素和水化学是一个很有价值的工具，运用它可以得出许多直观的结论，并最终对防渗加固有一定的指导作用。     

某滨海度假休闲区地下水分析与评价

以惠东县某滨海度假休闲区实例为依托,对该区地下水进行了分析与评价。查明各含水层／带的埋藏和分布规律,以及地下水与地表水之间的水力联系。阐明区内地下水的补给、径流、排泄条件,地下水动态的一般特征,初步阐明测区地下水化学特征。初步评价测区地下水资源,为开发利用地下热水资源提供了依据。     

某供水源地水质污染成因分析及保护对策

岩溶地区地质条件复杂,特别是在裸露型岩溶地区,岩溶发育强烈,地下岩溶管道空间往往与地表落水洞、伏流入口之间存在水力联系。因此岩溶地区水源地的脆弱性高,地表受污染水体通过落水洞、伏流入口等岩溶通道补给地下水,地下水一旦受到污染,污染物传播速度极快,一般来不及稀释或弥散就随水流到达水源地。该文对遵义市某供水源地水质污染成因分析,针对存在的污染问题,提出今后对地下水饮用水水源地的保护措施和意见。     

某供水源地水质污染成因分析及保护对策

岩溶地区地质条件复杂,特别是在裸露型岩溶地区,岩溶发育强烈,地下岩溶管道空间往往与地表落水洞、伏流入口之间存在水力联系。因此岩溶地区水源地的脆弱性高,地表受污染水体通过落水洞、伏流入口等岩溶通道补给地下水,地下水一旦受到污染,污染物传播速度极快,一般来不及稀释或弥散就随水流到达水源地。该文对遵义市某供水源地水质污染成因分析,针对存在的污染问题,提出今后对地下水饮用水水源地的保护措施和意见。     

宜万铁路马鹿箐隧道地下水示踪试验研究

宜万铁路马鹿箐隧道途经岩溶强烈发育、水文地质条件复杂的灰岩地层,地下暗河管道错综复杂。为了确定马鹿箐隧道区小马滩地下暗河系统与突水溶洞之间的水力联系及暗河系统的补给、径流和排泄条件,采用工业盐(NaCl)作为示踪剂的地下水单元(单一示踪剂)示踪试验方法进行探测。本次试验发现小马滩地下暗河是单一管道流地下暗河,以大气降雨、小马滩上游地表水及地下水为补给源,以蝌蚂口泉群为集中排泄点,龙潭是该暗河系统的天窗。小马滩地下暗河系统地下水流速快,地表水与地下水交替转化迅速,隧道岩溶突水与小马滩伏流的水力联系较弱。     

云南鹤庆西山岩溶地下水同位素及水化学分析

本文采用同位素和水化学分析的方法对鹤庆西山地区岩溶地下水循环特征进行了分析。根据区内水文地质边界条件,将研究区划分为5个岩溶水系统。利用氢氧同位素的分析结果,建立地表水与地下水的δD-δ18O关系曲线,分析地下水与地表水体的相互关系,并结合水化学分析方法对岩溶地下水水化学特征与地层岩性的关系进行了研究。结果表明,研究区地表水与地下水联系紧密,大气降水通过鹤庆西山地区地表岩溶洼地等补给地下水,区内地下水化学组分以Ca2+、Mg2+和HCO-3为主,水化学类型多为HCO3-Ca·Mg,少数水样水化学类型为HCO3-Ca,与岩溶水系统划分及地层岩性分布是一致的。     

天津复杂地层条件下深基坑回灌实测研究

天津地层条件较为复杂,在深大基坑实施工程降水过程中,易引起基坑周边地表和建筑物产生沉降变形,危及建筑物安全。通过开展地下水人工自然状态下的回灌,充分利用含水层之间的水力联系,实现对浅层水的有效补给,同时又不对基坑降水产生不利影响,最终确保了基坑和周边建筑物的稳定。     

河南平原第四系地下水氢氧同位素特征与补给分析

河南平原第四系地下水氢氧同位素分布特征,总体上由北向南呈渐高趋势,浅、深层地下水系统水的δ18O值变化规律基本一致。平原北部系统水的δ18O值最低,并随着距离黄河越来越近而变得愈来愈小,呈现出"∨"型变化的特征。平原南部系统水的δ18O值最高,并随着距离淮河越来越近而变得愈来愈大,呈现出"∧"的变化特征。平原中部系统水的δ18O值介于该二者之间,且变化较平缓。浅层系统水主要为大气降水补给。深层系统水受开采作用,使得浅层水的越流补给已成为主要的补给来源。此外,平原北部浅层系统水,黄河侧渗补给亦是沿岸地下水的重要补给来源;而平原南部浅层系统水在接受降水补给的同时,还受到淮河的排泄。     

示踪试验分析方法在地下工程水害治理中的应用研究

为查明地下水补给与运移规律,指导地下工程涌水注浆治理设计与施工,将用于大区域水文特征研究的水文示踪试验方法引入到地下工程涌水治理中。研究紫外光谱扫描精确测定超低浓度有色示踪剂的试验方法与数据分析技术,提出地下工程涌水区域的水力连通时间、补给相关系数、裂隙空间体积、地下水流速及压力等水文信息的获取方法;基于水文示踪试验数据分析结果,建立注浆治理中注浆材料选择依据与注浆参数确定方法。以某铁矿涌水工程治理为例,详细阐述水文示踪试验在涌水工程治理中的应用方法、数据处理过程及应用效果,希望对类似工程具有一定的借鉴意义。     

补给区温度季节性周期波动对承压含水层温度影响的解析研究

本文介绍了补给区温度季节性周期波动对承压含水层温度的影响,建立了相应的数学模型,并导出了其解析解。通过对该解析解的分析表明:补给区温度的季节性波动会导致含水层中温度的周期性波动,其波动幅度随与补给区距离的增加而减小,并具有一定的时间滞后性,且含水层中温度的波动情况与含水层的热容量和地下水的流速有关。还发现当含水层自身的热容量发生改变时,含水层中温度波动始终围绕着同一个均值进行波动,只有振幅和相位上发生相应变化,而当含水层中地下水的流速发生改变时,含水层中温度波动的均值也发生相应改变。对于含水层中没有温度波动的区域,温度随距补给区水平距离的变化率与含水层的热容量和地下水流速无关。     

水源热泵系统双管制双井回灌技术分析

地下水回灌技术在热泵技术的应用中由于受其回灌过程中物理、化学及生物作用产生的入渗介质堵塞现象而严重地影响到热泵的工作效率.通过对赣榆县财税业务大楼的水文地质条件进行了测试及分析,确定该建筑中央空调系统采用水源热泵系统,并详细分析了该系统的地下水取水有效性及回灌方案的可行性,研究了双管制双井回灌模式的回灌效果,得出双管制...     

循环抽注水作用下承压含水层砂土的变形特性

为探讨人工回灌和地下水位季节性变化等因素对承压含水层砂土变形特性的影响,利用FlowTracⅡ增量固结试验系统,设计了符合承压含水层砂土应力状态、符合抽注水应力路径的单向压缩试验,研究了循环抽注水作用对砂土变形特性的影响规律及抽注水作用下砂土变形特性的影响因素。试验结果表明:抽水作用(加载)下砂土产生压缩变形,注水作用(卸载)下,砂土变形呈现压缩和回弹两种现象,且砂土孔隙比大(密度小)时易发生注水压缩现象;循环抽注水作用下砂土总体呈现压缩变形特性,随抽注水循环次数的增加和前期固结压力增大,注水作用下砂土变形逐渐由压缩向回弹转化。基于砂土结构演变,构建了以弹性理论和最小势能原理为基础的抽注水作用下砂土变形机理,解释了注水作用过程中砂土变形呈现的回弹与压缩交替波动的试验现象,用试验结果总结了注水强度、前期固结压力、注水速率等因素对砂土变形特性的影响规律,验证了抽注水作用下砂土变形机理的合理性。     

Modeling the elution of organic chemicals from a melting homogeneous snow pack

Organic chemicals are often released in peak concentrations from melting snow packs. A simple, mechanistic snowmelt model was developed to simulate and predict the elution of organic substances from melting, homogeneous snow, as influenced by chemical properties and snow pack characteristics. The model calculates stepwise the chemical transport along with the melt water flow in a multi-layered snow pack, based on chemical equilibrium partitioning between the individual bulk snow phases. The model succeeds in reproducing the elution behavior of several organic contaminants observed in previously conducted cold room experiments. The model aided in identifying four different types of enrichment of organic substances during snowmelt. Water soluble substances experience peak releases early during a melt period (type 1), whereas chemicals that strongly sorb to particulate matter (PM) or snow grain surfaces elute at the end of melting (type 2). Substances that are somewhat water soluble and at the same time have a high affinity for snow grain surfaces may exhibit increasing concentrations in the melt water (type 3). Finally, elution sequences involving peak loads both at the beginning and the end of melting are simulated for chemicals that are partially dissolved in the aqueous melt water phase and partially sorbed to PM (type 4). The extent of type 1 enrichment mainly depends on the snow depth, whereby deeper snow generates more pronounced concentration peaks. PM influences the elution behavior of organic chemicals strongly because of the very large natural variability in the type and amount of particles present in snow. Urban and road-side snow rich in PM can generate type 2 concentration peaks at the end of the melt period for even relatively water soluble substances. From a clean, melting snow pack typical for remote regions, even fairly hydrophobic chemicals can be released in type 1 mode while being almost completely dissolved in the aqueous melt water phase. The model provides a mechanistic understanding of the processes that lead to chemical peak releases during snowmelt.     

Überwachung der Auswirkungen von Flussaufweitungen auf das Grundwasser mittels Radon

The restoration of the perialpine river Töss in a floodplain of northern Switzerland (Linsental) included the removal of bank reinforcements and tracer studies in the river and in oberservation wells of the adjacent alluvial groundwater. The river water is continuously recharging the aquifer system and the groundwater is used extensively as drinking water. Radon activity concentrations of freshly infiltrated groundwater are interpreted as radon groundwater age between the river and a well. A first flood after the restoration operations resulted in a widening of the river bed and in a reduction of the flow distance to the wells. Sixteen days after a second flood, the results of radon measurements were compared with those from before the restoration. The radon age of the groundwater between the river and the wells decreased, probably as a result of the reduction of the flow distances. Concentrations of autochthonous and coliform bacteria increased after the restoration operation and even more one day after the first flood. Thus the findings on the bacteria corroborate the interpretation of the radon concentrations. The restoration has not yet reduced the quality of the groundwater, which is pumped for drinking water. The study is contributing to the solution of land-use conflicts between river restoration and the supply of drinking water from the alluvial groundwater.     

Modeling and performance evaluation of shallow ground water heat pumps in Beijing plain, China

The use of groundwater for cooling and heating purposes is of interest from both the economical and the ecological perspective. The groundwater heat pump (GWHP) system utilizes groundwater as alternative renewable and clean energy source for space heating and/or cooling, withdraws water from a production well, passes it through a heat exchanger and discharges the water into an injection well. By utilizing the relatively stable temperature of groundwater, GWHP system can achieve a higher coefficient of performance. Due to the utilization of groundwater stored in the aquifer, the assessment of the hydraulic capacity of the aquifer based on numerical groundwater models is always needed for the optimum design and the efficient performance of GWHP. In this paper, numerical methods of underground heat-water transfer, energy balance method and thermal storage method were presented to calculate the capacity of unit area of shallow groundwater aquifer. The model results indicate that the numerical method, which is based on performance efficiency of GWHP, represents the behaviour of groundwater pumping/recharging processes, and serves better than energy balance method and thermal storage method, in addition it has been proven itself that this method has the advantages of energy saving and environmental protection. The calculated capacity is positively related to aquifer thickness. It is found that it is easy for ground water recharge in alluvial and pluvial fan located at the piedmont, while the calculated capacity is relatively smaller compared with that of south-east plain where it is not easy for groundwater recharge.     

寒地城市双层潜流池处理道路冰雪的方法及低温菌群适应性研究

中国北方寒地城市水资源紧张,冬季积雪的收集和处理难度较大,城市的可利用雪水堆放空间少,现有清雪方式低效耗能,造成环境污染。文中基于北方城市街道空间结构特点,利用街道两侧人行道和绿化带下方空间,设置双层潜流池作为冬季融雪和雪水收集与处理空间,从而实现常季雨水和冬季融雪的跨季连续运行,经格栅过滤颗粒物后,雨水和雪水可以在冬季气候条件下,通过微生物填料进行处置,COD的去除率达到80%以上,悬浮物的去除率在90%以上。通过分析不同工艺段填料表面的微生物种群,发现存在低温降解菌,能够在4~10℃左右存活,以Halomonas和TM6_Dependentiae_norank属为主的微生物为主要种群,能有效处理下层过滤池储存的雨水和雪水。处理后的雨水和雪水,待开春后可以用于街道喷洒和景观用水,从而为北方城市道路冰雪的快速处理和海绵城市战略在寒地的跨季实施,提供了一个有效的技术解决方案。     

某高速公路隧道出口端涌水对地表饮用水源的影响分析

保护饮用水源是隧道建设过程中必须重视的关键问题之一,若处理不当,易引起民众纠纷。本文以某在建高速公路隧道为例,在开展隧道涌水及地表水源点水质和水量动态监测的基础上,通过估算隧道排水的影响范围、分析隧道及水源点流量变化特征和开展隧道涌水来源识别工作,分析得出,隧道建设对水源点M1影响较小,对M2影响最为突出,与M3存在紧密联系,但有明显滞后,当其中之一出现流量增加或减少趋势后,另一者会在地下水系统动态调节并达到新的平衡后出现相反的变化趋势。上述结论可为科学评估隧道施工对饮用水源的影响和向隧道建设单位及有关部门解决因隧道施工而产生的水源纠纷提供科学决策依据。     

塔里木盆地与北山地区高放废物处置地质环境安全性对比分析

 参照地震发生频率、地块稳定特性等地质环境因素，结合水中的同位素及水化学特征分析，对塔里木盆地东部地区的核试验场地与北山地区作为高放废物处置场的预选址的安全性与合理性加以对比论述。研究结果显示，北山地区30 km以下的下地壳中存在着高导低速层，附近地区历史上曾发生过多次大地震，是一个相对不稳定地块。北山的地下水经分析并非是最初认定的“古水”，也不是来自当地降水，而是祁连山的降水通过深大断裂带补给的，北山附近的花海地区自流井的流量就达到了106 m3/a。北山地区的深层地下水为淡水，径流速度较快，下游为生态与环境的重点保护区额济纳盆地，因此会不利于将其作为高放废物处置场的选址。相比较而言，塔里木盆地东部地区历史上从未发生过较大的地震，地壳层中不存在高导低速层，同位素数据显示其地下水主要来自当地的降雨和河流的入渗补给，地下水中总溶解固体随着深度的增加而增加，地下水的循环周期较长，地下径流的最终排泄区是罗布泊荒漠戈壁地区，而且塔里木盆地东部军事禁区存在面积超过3 000 km2的花岗岩。因此在已经受到污染的核试验地区修建永久性处置高放废物要比北山地区更为安全，即使未来发生最不利的污染等事件也可以将对环境与生态的破坏降到最低。     

The water quality of the River Thame in the Thames Basin of south/south-eastern England

The water quality of the River Thame, a tributary of the River Thames in the Thames basin, is described in relation to point and diffuse contaminant inputs and runoff from permeable and impermeable bedrock geology with their own characteristic water quality. The data is examined to see if the market town of Aylesbury in the upper part of the catchment influences water quality. Previous studies highlighted the influence of Aylesbury sewage treatment works (STW) on soluble reactive phosphorus (SRP) concentrations in the river before and after phosphorus (P) stripping at the STW. Variations in water quality along the river are described and the study indicates that, apart from SRP, water quality determinants seem to be relatively unaffected by Aylesbury. The Thame water quality is compared with other catchment typologies and it is very similar to that of the main stem of the Thames even though the Thames is mainly Chalk groundwater fed. Differences in water quality largely link to the amount of STW effluent within the rivers and to the endmember compositions of the groundwater and near surface water sources.     

复合井在地下水源热泵工程中应用的试验研究

为研究复合井结构对回灌量的影响及复合井在地下水源热泵工程中的适用性,以沈阳市第一城A组团工程为实例,采用复合井结构的同井回灌形式进行现场试验,并对试验结果进行对比分析。由分析结果可以看出,复合井结构不同,其抽水量和回灌量也不同,复合井基本上可以满足项目用水量要求。由于采用复合井结构,解决了由于按照常规井布设空间不足的问题,但要根据具体地区含水层结构特点来进行,该工程已运行两个供暖期,运行正常。