陕西华电杨凌热电厂建设项目环境影响评价

根据陕西华电杨凌热电厂建设项目自身性质及其对地下水环境影响的特点,预测和评价建设项目投产后对地下水环境可能造成的影响和危害,采用数值模拟法进行预测与评价,建立能够正确刻画评价区地下水流动特征的地下水数值模型,并预测评价不同情景下对厂区地下水环境影响。针对这种影响和危害提出防治对策,从而达到预防与控制环境恶化,保护地下水资源的目的。     

燃煤灰场对地下水环境影响及防渗处理

平原地区电厂多以燃煤为主,其产生的灰渣利用率较低,需建灰场贮放。由于早期电厂建设时对灰场渗漏引起的环境问题缺乏认识,一般不采以专门的防渗措施,灰水渗漏对地下水环境产生了明显的影响。论文以济宁某电厂灰场为例,通过对平原灰场水位、水质在时间和空间上的数据对比表明灰场区地下水已遭受污染,其污染影响范围一般小于1km。根据场区地层结构和水文地质条件,本文提出了相应的防渗方案。     

天津港某石化仓储企业产品增项工程对厂区地下水污染影响预测研究

石油化学品泄漏会对地下水及土壤产生严重污染,破坏生态环境。本文以天津某石化仓储企业为研究对象,对该项目建设运行期和项目投产后对地下水环境造成的污染状况进行分析,分别采用解析法和数值法,建立能够正确刻画研究区地下水流动特征的地下水数值模型,评价不同情景下污染物对厂区地下水环境的影响。对污染物进入浅层含水层第100 d、1 000 d和服务期满30 a或超标范围结束时含水层中的丙酮、甲苯和石油类污染物超标范围进行模拟研究,结果显示:三种污染物均运移超出厂界,不满足《导则》要求,需要采取处理措施,重点在储罐区域周边及底部进行防渗处理,经处理后重新计算预测可知,在非正常状况下,石油类污染物入渗到潜水含水层1 000 d时,超标范围61.1m~2,影响范围91.6 m~2,最大运移距离5.16 m,超标距离4.34 m;石油类入渗到潜水含水层30 a时,污染物最大超标距离为9.69 m,超标范围仅为0.000 3 km~2,不会对厂界以外地下水产生影响,可以满足要求。     

某铅锌尾矿库对地下水环境影响及防治措施

铅锌尾矿的浸出液中含有重金属等对地下水环境有重要影响的污染因子。利用地下水数值模拟专业软件GMS,结合研究区水文地质条件,对不同工况下地下水环境的影响程度及范围进行模拟计算。结果表明,达到Ⅱ类工业固体废弃物处置场规定的防渗要求条件下,尾矿库运行浸出液下渗量有限(2.8 m3/d),并不会使区域地下水超出《地下水质量标准》Ⅲ类标准,而防渗层仅出现10%破损时,浸出液下渗量为(97.22 m3/d),使地下水下游方向50 m内地下水中Pb超出Ⅲ类标准,超标范围约0.0375 km2。反映出该类处置场中的防渗措施是对地下水环境保护的重要保证。     

西南岩溶山区某石化类场地地下水污染风险评价

本论文以西南岩溶山区某石化类场地为例,以污染场地风险评价导则作为指导,结合国内外地下水污染风险评价方法,在完成场地地下水污染风险识别以及源项分析的基础上,建立了符合场区实际水文地质条件的地下水水流及溶质运移数值模型,对不同情形下污染物泄露对场区浅层孔隙-溶蚀裂隙地下水的影响进行预测,结合预测结果建立了场区地下水污染风险...     

基于GMS的某垃圾填埋场地下水环境影响预测研究

以安徽省向山垃圾填埋场作为研究区,在分析场区水文地质条件的基础上,运用GMS中的MODF-LOW和MT3 D模块建立地下水流概念模型、数值模型及溶质运移数值模型,并根据取样结果确定污染物因子,模拟正常状况和非正常状况下污染物在地下水环境中的污染路径、污染羽迁移状况和污染物对地下水环境可能造成的影响.研究结果表明:评价区...     

靖安水源地地下水流模拟与预测

地下水数值模拟是地下水资源评价的重要方法之一。应用GMS软件建立靖安水源地的地下水流数值模型,利用该模型对设计的不同开采方案进行模拟,预测降水保证率95%条件下各方案开采20年后的地下水流场变化及水位变化情况。结果表明,当水源地总开采量为10万m3/d时,地下水流场能够达到稳定状态,中心水位降深较小,不会对生态环境造成明显影响。     

某规划区地下水环境影响评价研究

为预测某规划区地下水环境影响,本次研究运用FEFLOW地下水数值模拟软件,在分析研究区水文地质、地下水渗流场等的基础上建立了溶质运移数值模型。模拟结果显示,模型能够真实反映研究区实际水文地质条件,预测两种工况下的氨氮、氰化物和COD进行溶质运移变化规律,可以作为地下水环境影响评价的依据。同时,污水处理厂在事故工况下对地下水环境影响较大,规划区应制定相应的地下水风险应急预案并采取严格的防渗措施,减小对地下水的影响。     

基坑开挖及建筑加载对紧邻地铁的影响分析

以北京通州运河核心区某项目为例,系统地分析了深大基坑工程开挖、复杂地下水环境、超高层建筑加载对紧邻地铁的影响,总结并提出了紧邻地铁建设项目具体加固措施及施工建议。采用数值计算+SFIA联合技术,对建筑物上部结构加载引起的地铁变形进行分析,并与地铁长期沉降数据进行对比。工程实践及监测结果表明,加固措施及施工建议能够有效控制项目建设对紧邻地铁隧道的影响,数值计算+SFIA联合分析技术能够精准、有效预测地铁沉降变形,可为类似项目建设提供借鉴与参考。     

计算机水化学模型在地下水环境评价中的应用

介绍了基于平衡常数法的水溶液平衡组分分布的计算原理及其数学模型。在此基础上,以韩城电厂周原灰场区潜水环境为背景,对计算机水化学模型在地下水环境评价中的应用进行了探讨。与传统的水化学方法相比,该方法可以获得更多的信息,从而有助于分析地下水的化学特征及地下水与所处环境之间的关系和相互作用。      

The impact of tunneling construction on the hydrogeological environment of “Tseng-Wen Reservoir Transbasin Diversion Project” in Taiwan

Groundwater flow and the associated surface water flow are potential negative factors on underground tunnels. Early detection of environmental impacts on water resources is of significant importance to planning, design and construction of tunnel projects, as early detection can minimize accidents and project delays during construction. The groundwater modeling software package Groundwater Modeling System (GMS), which supports the groundwater numerical codes MODFLOW and FEMWATER, was utilized to determine the impact of tunneling excavation on the hydrogeological environment in a regional area around the tunnel and a local hot springs area, at the “Tseng-Wen Reservoir Transbasin Diversion Project”, in Taiwan. A hydrogeological conceptual model was first developed to simplify structures related to the site topography, geology and geological structure. The MODFLOW code was then applied to simulate groundwater flow pattern for the hydrogeological conceptual model in the tunnel area. The automated parameter estimation method was applied to calibrate groundwater level fluctuation and hydrogeological parameters in the region. Calibration of the model demonstrated that errors between simulated and monitored results are smaller than allowable errors. The study also observed that tunneling excavation caused groundwater to flow toward the tunnel. No obvious changes in the groundwater flow field due to tunnel construction were observed far away in the surrounding regions. Furthermore, the FEMWATER code for solving 3-D groundwater flow problems, in which hydrogeological characteristics are integrated into a geographic information system (GIS), is applied to evaluate the impact of tunnel construction on an adjacent hot spring. Simulation results indicated that the groundwater drawdown rate is less than the groundwater recharge rate, and the change to the groundwater table after tunnel construction was insignificant for the hot spring area. Finally, the groundwater flow obtained via the GMS indicated that the hydrogeological conceptual model can estimate the possible quantity of tunnel inflow and the impact of tunnel construction on the regional and local groundwater resources regime of the transbasin diversion project.     

Quantitative assessment of the impact of an inter-basin surface-water transfer project on the groundwater flow and groundwater-dependent eco-environment in an oasis in arid northwestern China

Inter-basin water transfer projects (IBWTPs) can involve basins as water donors and water receivers. In contrast to most studies on IBWTPs, which mainly impact the surface-water eco-environment, this study focuses on the impacts of an IBWTP on groundwater and its eco-environment in a water donor basin in an arid area, where surface water and groundwater are exchanged. Surface water is assumed to recharge groundwater and a groundwater numerical simulation model was constructed using MODFLOW. The model was used to quantitatively evaluate the impact of an IBWTP located in the upstream portion of Nalenggele River (the biggest river in the Qaidam basin, Northwest China). The impact involved decrease in spring flow, drawdown of groundwater, reduction in oasis area, and an increase in species replacement of oasis vegetation in the midstream and downstream of the river. Results show that the emergence sites of springs at the front of the oasis will move 2–5 km downstream, and the outflow of springs will decrease by 42 million m³/a. The maximum drawdown of groundwater level at the front of the oasis will be 3.6 m and the area across which groundwater drawdown exceeds 2.0 m will be about 59.02 km², accounting for 2.71% of the total area of the oasis. Under such conditions, reeds will gradually be replaced by Tamarix, shrubs, and other alternative plant species. These findings have important implications for the optimization of water resource allocation and protection of the eco-environment in arid regions.     

北京某拟建再生水厂地下水环境影响研究

研究区位于潮白河冲洪积扇中上部,第四系松散孔隙含水层颗粒粗大,易接受补给,地下水固有防污性能处于差和较差,地下水水质整体良好。采用数值模拟方法,建立了三维地下水流数值模型,对孔隙度、弥散系数进行了率定,利用GMS中的MT3DMS模块建立了溶质运移模型。选取COD作为模拟指标,根据模型对水厂投产30年后两种不同情景方案下地下水水质状况进行了预测分析。结果显示,在正常工况和处理流程出现故障两种条件下,再生水厂对周围地下水环境有一定程度影响,但重点研究区内地下水模拟浓度远小于《地下水质量标准》中Ⅲ类水标准,污染物浓度虽低,影响距离却很远,因此要建立覆盖全厂区的地下水长期监控系统,避免污染事故。     

水利工程建设对地下水影响的数值模拟分析

工程开挖及建成后对含水层结构的改造,无疑会对开挖区周围地下水造成影响。利用数值模拟方法分析预测某水利工程尾水渠开挖及建成后周围地下水水位的变化。预测结果,大开挖后周边地下水位将快速降低,且不同地段水位降幅不同,右岸阶地内水位降低约0.26~7.26 m,工程建成后,阶地内水位将逐渐恢复,但相比施工前水位仍降低0.09~0.38 m。分析水文地质结构,合理概化,建立数值模型,对于分析工程开挖对地下水的影响,是种有效方法。     

Characteristics of groundwater flow field after land creation engineering in the hilly and gully area of the Loess Plateau

In order to study the degree of influence and control mechanism to groundwater flow field caused by land creation engineering in the hilly and gully area of the Loess Plateau, based on the geological and engineering conditions of the first stage project of Yan’an new district in China, numerical simulation of groundwater flow is carried out by the Feflow and GIS technologies. From the simulation, punning measure relatively reduces infiltration recharge and artificial gravel drain increases groundwater seepage. The basic characteristics of groundwater flow field is controlled by the old and new topographies in the whole study area, and artificial gravel drain plays an auxiliary role in accelerating groundwater drawdown upstream and promotes groundwater rise downstream. According to differences of groundwater level and declining percentages of hydraulic gradient in the main and secondary gullies, dewatering of artificial gravel drain in the secondary gully is more effective than that in the main gully, which will yet play an important role in the future. The study results will make contributions to understand groundwater response to land creation engineering and will be beneficial to take necessary measures to prevent collapse of loess and failure of building foundation in the hilly and gully area of the Loess Plateau.     

南川黄泥垭隧道工程对水文地质条件的影响分析

隧道工程建设无疑对岩溶地区的水文地质环境地质带来巨大冲击。文章以重庆市南川区黄泥垭隧道工程为实例,采用地面调查、示踪试验、长观监测等方法进行综合研究,剖析隧道工程对隧址区水文地质环境的影响。研究结果表明:黄泥垭隧道工程改变了隧址区的地下水流场,疏干地表地下水、加剧干旱缺水程度,并随之出现新的人工水点——隧道涌水;同时隧道工程影响了水资源空间分配格局、降低了水资源利用率。      

Influence of South to North Water Transfer on groundwater dynamic change in Beijing plain

Beijing is a city of severe water shortage. The groundwater plays a key role in the water supply. However, the groundwater level has been gradually descending due to extensive pumping in consecutive drought years. How to satisfy the water demand and recover the groundwater level is an urgent work. With the implementation of the South to North Water Transfer Project, an opportunity has been provided for restoration of groundwater under over exploitation. On the basis of hydrogeology conditions of the Beijing plain, as well as the high-performance parallel computing platforms, a groundwater flow numerical model was established. And dynamic monitoring data of groundwater levels were used to calibrate the numerical model. The calculation results fit well with the measured data in the calibrated model. Therefore, the calibrated model can be used to predict the dynamic change of groundwater levels in the Beijing plain. The results show that several obvious depression cones of groundwater have been formed because of the rapid decline of groundwater levels in the Beijing plain in recent years. After the implementation of the South to North Water Transfer project and due to the restrictions on groundwater exploitation, the area of cone of depression will be reduced to different degrees, the central water level of depression cone will increase, and some cones of depression around wellhead will disappear. It is a benefit to relieve water shortage and control the development of land subsidence and the deterioration of the ecological environment.     

山东省日照市蓝色经济区工程建设适宜性评价

本文以山东省日照市蓝色经济区为研究区, 通过野外地质调查和室内综合分析, 选取场地稳定性、工程地质条件、地下水条件, 地形排水条件、地质灾害及其他因素6个一级评价因子, 构造活动、场地土类型、建筑场地类别等13个二级评价因子, 利用专家-层次分析定权法进行区内工程建设适宜性评价, 得到了相应工程建设评价分区图。评价结果表明, 日照市场地工程建设适宜性总体较好, 大部分地区适宜进行高层建筑工程建设, 占84.50%; 地下空间开发利用条件优越, 全区多数地区属于城市地下空间建设适宜区, 适宜性差及不适宜区主要分布在付疃河两岸附近和海岸附近、大型高速公路和铁路沿线一带区域及城区; 轨道交通建设适宜性良好, 小部分不适宜区主要集中在付疃河下游夹仓和小古镇一带及其沿海地区。评价结果可有效地服务于该地区规划布局、建设发展和工程选址, 具有重要的理论和实践指导意义。     

纳林河矿区某大型矿井地下水环境影响数值模拟研究

矿井采煤对地下水环境的影响主要为对具有供水意义的含水层水位及水量产生影响,确定采煤引起地下水水位降及漏失量是煤矿地下水环境影响评价的关键。以纳林河矿区某大型矿井为例,运用Visual MODFLOW建立模拟区地下水流数值模型,利用实测流场和长观孔的动态观测资料识别和验证数值模型,利用模型来预测采煤对第四系-白垩系含水层水位及水量的影响。模拟结果显示:前25年采煤引起地下水最大水位降为3.6 m,引起地下水的漏失量最大为141.87万m^3/a,占矿井涌水量的29.88%;利用矿化度法确定的越流量占矿井涌水量的6.39%~34.89%,模拟结果基本合理,可作为矿井采煤对地下水环境影响的研究依据。     

Visual MODFLOW在煤矿建设地下水环境影响评价中的应用 ——以甘肃省灵台县安家庄煤矿为例

结合甘肃省灵台县安家庄煤矿地下水环境影响评价实例,建立了评价区水文地质概念模型,并基于Visual MODFLOW对评价区地下水进行了数值模拟计算和验证;预报了设计开采条件下研究区不同含水层的地下水水位。预报结果表明:矿坑排水使得煤层所在含水层出现疏干现象,并且疏干范围随着开采范围的增加而不断扩大;在煤矿开采作用下,随着模拟时间的延续,煤系层上覆白垩系洛河组—宜君组含水层地下水位降落漏斗的范围及地下水位下降幅度不断增大,但降落漏斗的范围基本上不超过采空区范围;煤矿开采对白垩系环河组含水层无影响,至矿区开采期结束,未引起含水层水位下降;对上部孔隙、裂隙潜水含水层也无影响,至矿区开采期结束未引起含水层水位下降。