Grab samples of drinking water collected from reservoirs and from creeks flowing over pristine land, farmland or land having mixed use were analysed for their physicochemical and microbiological characteristics. A significant difference between sites for conductivity and sites for pH was noted using a two‐way anova. No significant interactions were detected between any of the other parameters: Giardia, Cryptosporidium, Escherichia coli, coliforms, plate count, turbidity or rainfall.

Construction site erosion and resulting sedimentation constitutes one of the greatest non-point source pollution threats to our nation’s waterways. Erosion control practices are important aspects of any construction project due to their ability to limit the process of erosion. Testing erosion control practices under simulated rainfall representative of conditions experienced on construction sites is important to better understand their erosion reduction capabilities. Full-scale testing using simulated rainfall has been shown to provide controllable and repeatable results, in comparison to field-testing under natural conditions. Therefore, the focus of this study was to design, construct, and calibrate a pressurized rainfall simulator testing apparatus capable of accurately and repeatedly simulating rainfall intensities of 50.8, 101.6, and 152.4 mm/hr (2.0, 4.0, and 6.0 in/hr) for 20-min intervals. The developed testing apparatus consisted of a 12 m (40 ft) long by 2.4 m (8.0 ft) earthen slope at a 3H:1V slope. Ten sprinkler risers at a height of 4.27 m (14 ft) were installed around the perimeter of the slope to create a uniform distribution of rainfall. Data collection procedures consisted of collecting and analyzing rainfall depth, drop size distributions, and sediment concentrations. The optimum location for each sprinkler riser, as well as the most accurate nozzle configuration, were determined through test procedures developed for this study. Through calibration testing, the simulator was found to produce accurate rainfall intensities with relative errors of 1.17–4.00% of the target intensities. Uniformity of rainfall distribution ranged from 85.7 to 87.5%. Average drop sizes were determined to be between 2.35 and 2.58 mm (0.093 to 0.102 in.).

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The increasingly common occurrence of eutrophic conditions in shallow lakes and reservoirs, including the presence of potentially toxic blue-green algae, has given rise to water-quality concerns throughout the world. The need to undertake active catchment management to improve raw-water quality is a key component of the new EC Water Framework Directive.This paper describes the investigations which were undertaken in Tallinn (the capital of Estonia, the northernmost of the Baltic States) to develop an integrated approach to catchment and lake management, in order to improve the quality of the surface-water resource which provides 90% of the total drinking-water needs of the city. Several tools, including 'geographical information systems' and spreadsheet-based financial and waterresources models, were developed to investigate the source of the water-quality problems. Practical solutions comprising an innovative and cost-effective catchmentmanagement approach to overcome the seasonal rawwater quality issues, whilst also reducing treatment plant operating costs, are described. Some of the recommendations have been tested by Tallinn Water following the investigations, and some improvements in raw and treated water quality have been attained.

Remining is the surface mining of previously-mined and abandoned surface and underground mines to obtain remaining coal reserves. Remining operations create jobs in the coal industry, produce coal from previously-disturbed areas, and improve aesthetics by backfilling and revegetating areas according to current reclamation standards. Remining operations also reduce safety and environmental hazards by sealing existing portals and removing abandoned facilities, enhance land use quality, and decrease pre-existing pollutional discharges. Ten sites in the Appalachian Coal Region were selected to: I) compare the costs associated with remining and reclaiming a site to current standards vs costs associated with reclaiming the site by abandoned mine land (AML) programs, and 2) evaluate water quality before and after remining. All of the remining operations in our study resulted in environmental benefits. Dangerous highwalls were eliminated, spoil piles were regraded, coal refuse left on the surface was buried, and sites were revegetated with a mixture of grasses and legumes to provide productive post-remining land uses. In all but two cases, coal mined and sold from the remining operation produced a net profit for the mining company. While AML reclamation removes ha7.a.rds and improves aesthetics on AML sites, remining these I 0 sites saved the AML reclamation fund an estimated $4 million. Water quality after remining improved in all cases. Impediments to remining AML sites should be removed so that mining companies will actively select previously-disturbed and abandoned sites for remining and reclamation.