Preliminary Hydrogeological Characterisation for Proposed Covered Infiltration Galleries at CSIRO Laboratory, Floreat, Western Australia.Report for Water for a Healthy Country Flagship and Water Corporation, Western Australia

[摘要] Executive Summary:Further work is recommended to more fully characterise the infiltration galleries pilot site.Some of the aims should be to determine soil moisture characteristic curves for different soils to aid modeling of the unsaturated flow conditions, and to conduct a pumping test and tracer tests that will assist with characterising the fate and transport of solutes and microbes.Additional drilling and coring through the profile of superficial aquifer at this site (~30 m) would assist with determining the presence of any cavities in the Tamala Limestone as well as other heterogeneities.Compact limestone or cemented sand bands and/or cavities might result in heterogeneous flow and different hydrobiogeochemical conditions. Additional work is also needed to determine the geochemical reactions that may occur in the aquifer as the infiltration galleries receive reclaimed water.The high pH of treated effluent could significantly affect solubility and precipitation reactions, which have a direct effect upon plugging rates, recovered water quality, and possible pre- or post-treatment requirements (Pyne 1995).The hydrochemistry of treated effluent should be analysed to determine necessary pre-treatments.Geochemical modelling is recommended to evaluate whether the mixing of groundwater and reclaimed water in various proportions can potentially result in precipitation reactions that may plug the aquifer (PYNE 1995). Future work at the site should also consider a range of other issues that include: control and prediction of nitrate levels, the potential for physical clogging by suspended solids, biofouling and other complex microbiological processes, such as the impact of environmental conditions (e.g. temperature, biological load, pH, total phosphorus, nitrate, total nitrogen, DOC, flow sequence, total iron, DO) on microbial growth.

[发布机构] CSIRO

[学科分类] 地球科学(综合)