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This paper discusses the use of three-dimensional mapping software SolidWorks as a platform to build a parametric model of coal mine filling equipment and a model library of the equipment. The Solidworks software is used to create a near-realistic virtual environment to simulate and analyze the process of building a high-water filling station. In this way, designers can detect potential design flaws early and then optimize the design as much as possible before actual construction.

Samples of sandwiches were taken from all petrol filling stations in the Bolton area selling such foodstuffs. These were bacteriologically examined and, when the results were obtained, all the petrol stations were visited and advice was given where improvements could be made. Resampling was carried out and the results were compared with the initial samples. The second set of results indicated a significant improvement in microbial flora. Further recommendations were made where necessary and it was possible to produce a Code of Practice from the results obtained.

The purpose of this paper is to investigate the physico-chemical properties of the groundwater surrounding the Solous (solid waste dumpsite) at Isheri, Lagos, Nigeria.

In total, 40 groundwater samples were collected from ten pre-determined sampling stations. Three sample stations were established before the dumpsite; three sample stations were located in the vicinity of the dumpsite in the direction of the leachate plume, while the remaining four sample stations were situated further away and acted as a control. Sampling was carried out four times during the study period (twice each in the rainy and dry seasons). The parameters measured in situ were air and water temperatures (using mercury-in-glass bulb thermometer) and pH (using pH meter). Calcium and magnesium contents were measured using the Ca-Mg indicator; sodium content was measured using the flame emission spectrophotometry and phosphate was measured using the flame photometry. The selected heavy metals (copper, iron, lead, cadmium, zinc and manganese) were measured by using the atomic absorption spectrometer. The oxygen parameters, such as dissolved oxygen, biological oxygen demand, chemical oxygen demand and organic matter, were determined titrimetrically. The data obtained were subjected to descriptive statistics and analysis of variance (ANOVA).

The results showed that many parameters had higher values in the dry season than in the rainy season. Temperature (27.75±0.95°C), alkalinity (211.37±82.78 mg/LCaCO₃), phosphate (0.30±0.07 mg/L) and sulfate (2.78±0.35 mg/L), sodium ion (41.95±18.86 mg/L), dissolved oxygen (2.98±0.57 mg/L) and COD (33.54±4.50 mg/L) had higher mean values in the dry season than in the rainy season. On the other hand, the mean values of electrical conductivity (1,224.85±370.63), nitrate (0.01±0.003 mg/L), chloride (98.76±21.58 mg/L), calcium ion (5.38±0.68 mg/L), magnesium ion (3.05±0.05 mg/L), BOD (22.37±2.20 mg/L) and pH (6.31±0.18) were higher in the rainy season than in the dry season. The heavy metals (iron 1.10±0.05 mg/L, lead 0.12±0.07 mg/L, manganese 0.01±0.004 mg/L, copper 0.15±0.003 mg/L, zinc 0.07±0.004 mg/L and cadmium 0.02±0.02 mg/L) were fairly uniform all year round. There was also a marked decline in the values as one moved away from the dumpsite.

The implication of the findings is that human health is remarkably dependent upon safe and clean drinking water. Preserving the water resources and hindering them from pollution is preferred to the treatment of polluted water and rendering it suitable for consumption. The high electrical conductivity values obtained in the groundwater samples near the dumpsites are an indication of the effect of leachate on the groundwater quality. The high concentrations of dissolved solids in the groundwater may decrease the palatability and may cause gastro-intestinal irritation in humans, and laxative effect particularly on transits.

The pollutants from the various waste components disposed at the dumpsite percolate into the ground to pollute the groundwater. The groundwater is transported in the line of flow away from the vicinity of the dumpsite to pollute the groundwater in the area. The extent of contamination level of groundwater quality due to leachate percolation depends upon a number of factors like chemical composition of leachate, rainfall, depth and distance of the well from the dumpsite. Groundwater samples of different depths and distances from dumpsites were analyzed in the present study to understand the level of a combination.

In this chapter it is shown how economic evaluation algorithms of water use can be integrated into a long-term water management model such that surface-water availability and economic evaluation of various levels of water availability to different uses can be modeled simultaneously. This approach makes it possible to include essential features of economic analyses of water use into water resource modeling and thus improves the capability of such models to support decision making in water management. This is especially relevant for the implementation of the Water Framework Directive, which requires economic analyses to be included in the decision process about future water management strategies.

The water management simulation model WBalMo is presented and the integration of economic-evaluation algorithms is demonstrated for the examples of surface-water use for fish farming and for filling open-cast mining pits in order to achieve acceptable water-quality levels in the emerging pit lakes. Results of applying this integrated evaluation approach are shown for different water management scenarios under conditions of global change in the East German Spree and Schwarze Elster river basins, where water scarcity is an urgent issue. Among the lessons which are drawn by the authors one lesson reads that integrating economic evaluation algorithms into a pre-existing model might bring enormous problems. Therefore, such model approaches should be developed together by water engineers and economists in an interdisciplinary endeavor right from the start.

GRADUALLY, industrial leaders are becoming optimistic. Business chiefs on both sides of the Atlantic are saying that, at long last, they can see the light at the end of the tunnel.

To establish relationships between effective vertical stress‐void ratio and hydraulic conductivity‐void ratio on high water content dredged clays, which are then used to predict the field consolidation behavior.

The large strain consolidation model is used for numerical modeling of large‐strain self‐weight consolidation. Material parameters determined from seepage‐induced consolidation tests provided satisfactory predictions of field compression behavior.

It is shown that realistic estimates of self‐weight consolidation behavior of dredged sea bottom sediments stored on land can be made by using a seepage‐induced consolidation test system and an appropriate consolidation model such as CS2, which is very important in storage capacity design and reclamation planning of such storage areas.

In this paper, the findings are presented of an experimental investigation of the consolidation behavior of Golden Horn dredge material using a seepage‐induced testing system. The experimentally determined consolidation properties have yielded useful relationships for the variation of void ratio with effective stress and coefficient of permeability with void ratio, and use of these has enabled a realistic prediction of the observed behavior.

Concrete is the most basic of building materials and yet, in the hands of the expert, is capable of providing strength, durability and even elegance far in excess of many of its manufactured competitors. The technology is by now well established but the production of concrete of a consistently good quality is by no means simple.