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Every workday the city of Bílina, with the I/13 road running through it, suffers from traffic congestion. The road is designed as dual carriageway outside Bílina but only as a single carriageway inside the city. Three roundabouts further complicate the situation. As a solution a 1,3 km long tunnel going under the city was proposed. The preliminary geotechnical investigation describes the geological conditions of the area, suggests the most appropriate localisation details of the tunnel, points out several complications that can be expected and finally offers solutions to mitigate them.

Sungai sebagai sumber air permukaan seringkali menghadapi masalah penurunan kualitas air secara serius. Sumur filtrasi bantaran sungai bisa digunakan untuk memperbaiki kualitas air sungai sebagai sumber air bersih. Penelitian ini bertujuan untuk menganalisis karakteristik geologi dan hidrogeologi tapak filtrasi bantaran sungai, mengukur penurunan muka air tanah sumur akibat pemompaan pada bantaran sungai Cihideung Bogor, menduga nilai kelulusan hidraulik material akuifer berdasarkan analisis uji pemompaan sumur di bantaran sungai. Lingkup penelitian meliputi penyelidikan geologi dan hidrogeologi, penyelidikan geofisika bawah permukaan dengan metode geolistrik, pembuatan sumur, uji pemompaan dan penentuan karateristik hidraulik akuifer. Lokasi uji pemompaan di bantaran Sungai Cihideung terletak pada kipas vulkanik Gunung Salak dengan lapisan akuifer terdiri dari lapisan pasir halus, pasir kasar dan lempung pasiran. Berdasarkan karakteristik penurunan muka air tanah akibat pemompaan sumur di bantaran sungai, imbuhan air tanah dominan berasal dari Sungai Cihideung, dengan kurva muka air tanah sumur 1 lebih responsif dari sumur 3. Lokasi penelitian sesuai untuk pembangunan sumur filtrasi bantaran sungai dengan memiliki nilai konduktivitas hidraulik 2,5 4,32 m/hari. Metode Thiem dan aplikasi Aquifer Test Versi 4.2 memberikan hasil yang baik dalam menduga nilai kelulusan hidraulik pada lokasi penelitian.

Some regions of the Greenland ice sheet, where snow accumulation and melt rates are high, currently retain substantial volumes of liquid water within the firn pore space throughout the year. These firn aquifers, found between ~10 and 30 m below the snow surface, may significantly affect sea level rise by storing or draining surface meltwater. The hydraulic gradient and the hydraulic conductivity control flow of meltwater through the firn. Here we describe the hydraulic conductivity of the firn aquifer estimated from slug tests and aquifer tests at six sites located upstream of Helheim Glacier in southeastern Greenland. We conducted slug tests using a novel instrument, a piezometer with a heated tip that melts itself into the ice sheet. Hydraulic conductivity ranges between 2.5 × 10−5 and 1.1 × 10−3 m/s. The geometric mean of hydraulic conductivity of the aquifer is 2.7 × 10−4 m/s with a geometric standard deviation of 1.4 from both depth specific slug tests (analyzed using the Hvorslev method) and aquifer tests during the recovery period. Hydraulic conductivity is relatively consistent between boreholes and only decreases slightly with depth. The hydraulic conductivity of the firn aquifer is crucial for determining flow rates and patterns within the aquifer, which inform hydrologic models of the aquifer, its relation to the broader glacial hydrologic system, and its effect on sea level rise.

Hydraulic conductivities and specific storage coefficients of fractures and matrix in Slovenian carbonate aquifers were determined by Barker’s method for pumping test analysis, based on fractional flow dimension. Values are presented for limestones and mainly for dolomites, and additionally for separate aquifers, divided by age andlithology in several groups. Data was obtained from hydrogeological reports for 397 water wells, and among these, 79 pumping tests were reinterpreted. Hydraulic conductivities of fractures are higher than the hydraulic conductivities of matrix, and the differences are highly statistically significant. Likewise, differences are significant for specific storage, and the values of these coefficients are higher in the matrix. Values of all coefficients vary in separate aquifers, and the differences can be explained by diagenetic effects, crystal size, degree of fracturing, andcarbonate purity. Comparison of the methods, used in the reports, and the Barker’s method (being more suitable for karstic and fractured aquifers), shows that the latter fits real data better.

ABSTRACT Transmissivity is an important hydraulic parameter to determine the amount of water passed horizontally across a given saturated thickness of an aquifer. The techniques to quantify this parameter, such as grain size analyses or pumping tests, can have limitations of time/spatial scale, viability, or economically. One technique that can be used, but little adopted, is the capture zone analysis. In this paper, capture zone analytical equations were used to estimate transmissivity values in order to verify the effectiveness of this methodology as alternative in situations where other traditional methods present implementation difficulties. The results were compared with field data estimated by aquifer tests conducted in the same region. A sensitivity analysis was also performed to identify possible discrepancies between the analytical and field data results. The aquifer studied was the Sete Lagoas Karst Aquifer in the urban region of the municipality of Sete Lagoas, Brazil. The method proved to be a viable and economical tool, where the analytical values compared to the aquifer tests showed similarities, being confirmed by a sensitivity analysis. However, a reliable potentiometric surface map, which enables the identification of the parameters for analytical capture zone equations, is needed.