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In the northwestern area of Basel, Switzerland, a tunnel highway connects the French highway A35 (Mulhouse-Basel) with the Swiss A2 (Basel-Gotthard-Milano). The subsurface highway construction was associated with significant impacts on the urban groundwater system. Parts of this area were formerly contaminated by industrial wastes, and groundwater resources are extensively used by industry. During some construction phases, considerable groundwater drawdown was necessary, leading to major changes in the groundwater flow regime. Sufficient groundwater supply for industrial users and possible groundwater pollution due to interactions with contaminated areas had to be taken into account. A groundwater management system is presented, comprising extensive groundwater monitoring, high-resolution numerical groundwater modeling, and the development and evaluation of different scenarios. This integrated approach facilitated the evaluation of the sum of impacts, and their interaction in time and space with changing hydrological boundary conditions. For all project phases, changes of the groundwater system had to be evaluated in terms of the various goals and requirements. Although the results of this study are case-specific, the overall conceptual approach and methodologies applied may be directly transferred to other urban areas.

As permafrost thaws in the Arctic, new subsurface pathways open for the transport of groundwater, energy, and solutes. We identify different ways that these subsurface changes are driving observed surface consequences, including the potential for increased contaminant transport, modification to water resources, and enhanced rates of infrastructure (e.g. buildings and roads) damage. Further, as permafrost thaws it allows groundwater to transport carbon, nutrients, and other dissolved constituents from terrestrial to aquatic environments via progressively deeper subsurface flow paths. Cryohydrogeology, the study of groundwater in cold regions, should be included in northern research initiatives to account for this hidden catalyst of environmental and societal change.

Surabaya’s public facilities and rapid infrastructure development will change the physical environment and require careful attention in all aspects of development. One aspect is the location determination of subsurface objects such as gas pipes, electrical cable lines, and water pipes. Lack of pipeline management and mapping can fail underground pipeline identification during excavation. The subsurface water pipe is one of the most important things to support people’s needs. Knowing the location of these pipes is essential for government agencies in carrying out maintenance, pipeline development, and repair activities. We identified the subsurface water pipeline using the Ground-Penetrating Radar (GPR) method. It is because of a non-destructive working type and very well applied in investigating underground infrastructure with significant electromagnetic contrast with the surrounding soil. We conducted this research around Surabaya Zoo and Joyoboyo Terminal (SZJT) track. We conducted data acquisition with the GPR GSSI SIR-3000 system with a shielded antenna frequency of 270 MHz on 21 measurement lines (JB07 to JB27). The aim is to determine the location, depth, and structure of the subsurface water pipeline at the research location. We processed the measurement data using MatGPR R-3.1 software by adjusting signal position, dc removal, dewow, median filter, inverse amplitude decay, background removal, K-L filter, bandpass filter, and time-to-depth conversion. We conducted 2-D and 2.5-D modeling to visualize the water pipeline. A hyperbolic anomaly, suspected to be a water pipe, is detected from the presence of high amplitude at a depth of 1 – 2 meters, which we saw in almost every line with velocity values from 0.0609 - 0.113 m/ns and dielectric constant value of 7.05 – 24.27. The 2.5-D modeling shows that the water pipeline continues from the research location’s south (Surabaya River) to the north.

Water availability for human and ecological uses depends on both water quantity and water quality. The U.S. Geological Survey (USGS) is developing strategies for prioritizing regional-scale and watershed basin-scale studies of water availability across the nation. Previous USGS ranking processes for basin-scale studies incorporated primarily water quantity factors but are now considering additional water quality factors. This study presents a ranking based on the potential impacts of geogenic constituents on water quality and consideration of societal factors related to water quality. High-concentration geogenic constituents, including trace elements and radionuclides, are among the most prevalent contaminants limiting water availability in the USA and globally. Geogenic constituents commonly occur in groundwater because of subsurface water–rock interactions, and their distributions are controlled by complex geochemical processes. Geogenic constituent mobility can also be affected by human activities (e.g., mining, energy production, irrigation, and pumping). Societal factors and relations to drinking water sources and water quality information are often overlooked when evaluating research priorities. Sociodemographic characteristics, data gaps resulting from historical data-collection disparities, and infrastructure condition/age are examples of factors to consider regarding environmental justice. This paper presents approaches for ranking and prioritizing potential basin-scale study areas across the contiguous USA by considering a suite of conventional physical and geochemical variables related to geogenic constituents, with and without considering variables related to societal factors. Simultaneous consideration of societal and conventional factors could provide decision makers with more diverse, interdisciplinary tools to increase equity and reduce bias in prioritizing focused research areas and future water availability studies.

The development and use of underground space is a necessity for most cities in response to rapid urbanisation. Effective underground land administration is critical for sustainable urban development. From a land administration perspective, the ownership extent of underground assets is essential for planning and managing underground areas. In some jurisdictions, physical structures (e.g., walls, ceilings, and utilities) are also necessary to delineate the ownership extent of underground assets. The current practice of underground land administration focuses on the ownership of underground space and mostly relies on 2D survey plans. This inefficient and fragmented 2D-based underground data management and communication results in several issues including boundary disputes, underground strikes, delays and disruptions in projects, economic losses, and urban planning issues. This study provides a review of underground land administration from three common aspects: legal, institutional, and technical. A range of important challenges have been identified based on the current research and practice. To address these challenges, the authors of this study propose a new framework for 3D underground land administration. The proposed framework outlines the future research directions to upgrade underground land administration using integrated 3D digital approaches.

It is axiomatically true that urbanization in India's metropolises and large cities has been exacerbated since the beginning of the millennium, consuming the natural and semi-natural ecosystem on the outskirts of the city, resulting in a zone with a distinct climate known as urban climate. Such a climate—the result of a built-up environment is distinctly different from the natural climate as the paved surface and concrete skyscrapers not only destroy the natural ecosystem, it peculiarly induce a different kind of insolation, cooling and air drainage were lacking in green space, water bodies and open space cannot accommodate with environmental rhythm properly, resulting into the accumulation of heat, ecological derangement of subsurface soil which can easily be predicted by GIS analysis. This paper is an attempt to measure urban growth and its impact on the environment in the metropolitan city Kolkata. The use of satellite data and GIS techniques to detect urban expansion is a highly scientific strategy. Using geospatial techniques, the current study attempts to examine major urban changes in Kolkata and its surroundings from 1988 to 2021. Landsat 5 TM and Landsat 8 OLI temporal data are used to identify land-use change through unsupervised classification; Spectral Radiance Model and Split Window Algorithm method are used for identifying land surface temperature change. SRTM DEM (30 m) has been used to identify flood risk zones and several spectral indices like Normalized Difference Vegetation Index and Modified Normalized Difference Water Index are a further extension for environmental assessment. By all such suitable methods, a clearer change in an urban environment is detected within the period of 33 years (1988–2021). The result shows that the population changes, vegetation cover and built-up area, and accessibility are at a rapid rate. These changes are causing major environmental degradation in the city. The classification result indicates that appropriate land use planning and environmental monitoring are required for the long-term exploitation of these resources.

Purpose The purpose of this study was to investigate the likely causes of failure of some sections of road pavements in Ajaokuta, Northcentral Nigeria. This was achieved through a geotechnical assessment of subgrade soils in affected areas. Design/methodology/approach The methods entailed field and laboratory methods and statistical analysis. Subgrade soil samples were retrieved from a depth of 1,000 mm beneath the failed portions using a hang auger. The soils were analyzed for natural moisture content (NMC), Atterberg limit (liquid limit, plastic limit and linear shrinkage), grain size distribution, compaction and California bearing ratio (CBR), respectively. Findings The results of the geotechnical tests ranged from NMC (12.5%–19.4%), sand (84%–98%), fines (2%–16%), LL (16.0%–32.2%), PL (17%–27.5%), LS (2.7%–6.4%), PI (2.5%–18.4%), maximum dry density (1756 kg/m2–1961 kg/m2), optimum moisture content (13.2%–20.2%), unsoaked CBR (15.5%–30.5%) and soaked CBR (8%–22%), respectively. Pearson’s correlation coefficient performed on the variables showed that some parameters exhibited a strong positive correlation with r2 > 0.5. Research limitations/implications Funding was the main limitation. Originality/value Comparing the results with Nigerian standards for road construction, and the AASHTO classification scheme, the subgrade soils are competent and possess excellent to good properties. The soils also exhibited very low plasticity, a high percentage of sand, high CBR and low NMC, which implies that it has the strength required for road pavement subgrades. The likely causes of the failures are, therefore, due to the use of poor construction materials, technical incompetence and poor compaction of sub-base materials, respectively.

When decarbonizing a state-wide energy system by introducing a growing share of renewable energies, underground energy storage can help to deal with fluctuating electric grid feed-in from renewables like wind power. Since besides energy storage other subsurface usages can claim or effect possible scarce suited underground spaces and interact with other usages at the surface, subsurface spatial planning is a growing field of interest for state authorities and in science now. Combining two-dimensional surface geodata on concerned fields like regional planning and energy infrastructure with three-dimensional geological data into one coherent data model could therefore support spatial planners in identifying and locating underground entities suited for energy storage. In this paper, a volumetric grid-based concept to integrate two- and three-dimensional geodata into one coherent data framework is implemented, including available data sets on geology, energy infrastructure and existing spatial plans. Missing spatial data on regional electric energy production and heat energy demand are derived from available primary data. Upon this data basis, a self-developed open source-based 3D webGIS prototype is utilized to identify and visualize potential underground spaces for a compressed air energy storage use case scenario at the example of the federal state of Schleswig–Holstein in North Germany. A first basic and a subsequently extended query via the 3D webGIS on the developed data model provide spatial information on search domains for potential energy storage sites in salt rock structures that could be integrated into emerging subsurface spatial planning.

It is believed that isolated subsurface structures of an infrastructure do not ventilate through opening(s) in manhole covers. The literature has almost no information on this topic. This study reports on considerations involved in the development and utilization of a method to study this question. Carbon monoxide (CO) is readily obtainable in engine exhaust, easily detectable at very low concentration, and is relatively safe to handle, which makes it ideal for use as a tracer gas. Transfer into the airspace of the structure was carried out using metal tubing. This study examined the engine operating time and the number of openings in a manhole cover. CO was measured using four instruments in the vertical profile. It was found to generally decrease in a narrow band, initially linearly through a curvilinear region and a linear tail. Clearance of most of the contaminant occurred rapidly during the first part of the process. A decrease to 25 ppm required from 439 min (7 openings) to 1118 min (1 opening). Ambient temperature and near-surface air flow likely influenced these values. The measurement profiles strongly suggest that the atmosphere in the airspace was rapidly and thoroughly well-mixed. The methodology developed and reported here is suitable for a more expanded investigation, the intent being to identify modifications of the design to optimize the process.

This article describes development and confirmatory testing of a method to study the evaporation of a volatile solvent containing ignitable ingredients in an isolated subsurface structure, a type of confined space. Accidental spillage and surreptitious disposal of chemical products in streets create a risk of fire and explosions in these structures. Development of the method included consideration about instrument safety; personal exposure; volume of the structure (2.5 m3); evaporation rate; temperature of the airspace; and number of opening(s) in the manhole cover. Confirmatory testing utilized 10 mL of lacquer thinner (60% to 80% toluene, 10% to 20% methylethyl ketone (MEK), 5% to 10% methanol and 1% to 9% acetone) on a wetted paper towel positioned near the bottom of the structure. This methodology produced a maximum of 2150 ppm of ‘isobutylene units’ on a PID (PhotoIonization sensor) positioned about 15 cm above the sample. This concentration corresponds to about 1140 ppm of toluene (less than 10% of the Lower Flammable Limit of 12,700 ppm). This method offers a stable, safe platform for study of the process. Evaporation of solvent and exchange between the external atmosphere and the airspace regulate the concentration of vapor, which can typically persist for 24 to 48 h.