WP3: Tools and development of water balance modeling
Need:
Estimation of water balances is essential for every method to reduce waste water loading from the mines. On a mining district it is essential to simulate the effect of soil type, soil surface structure and vegetation and slopes on soil moisture variation, evaporation and runoff generation. The movements of surface water, recharge of ground water and generation of ground water runoff within the mining district need also to be simulated.
To establish capabilities for introducing online and offline data to the water balance model and to establish capabilities to export water balance data from the models to the reports online. Ultimate aim is to have continuously updating water balance models that facilitate the management and predictive control of mine site water balance. As water balance of a mine is linked to quality and recycling of different water fractions at mine site: runoff waters, mine dewatering waters, process effluent waters and seepage waters from tailings and waste rock areas, the quality can’t be neglected in managing mine water balance.
Problem:
We neither do have forecasting system for surface nor ground water balances in mining areas. There are various separate models for different targets.
Solution:
We develop the water balance calculations of WSFS for pilot sites using the data from WP1. The calculations include surface waters (SYKE), ground waters (GTK) and process waters (VTT and selected mine).
Transport of tracer substances, such as oxygen, need to be included to ensure a correct simulation of the origin and mixing of waters. Also colour and temperature of waters in the channels and reservoirs need to be taken into account for correct estimation of water temperature and evaporation from water surface. Simulation of runoff generation and water movements are connected to weather forecasts for providing a range of possible water volume entering the reservoirs in the near future.
We will develop a continuously updating solution for mine site water balance. In this model the water cycle of a mine site is interconnected with the general hydrologic water cycle and therefore it includes both natural waters and process waters. The work package establishes the capabilities for introducing online and offline data to the modelling software and capabilities to continuously export and visualize the data from the calculations. We shall apply the hydro meteorological forecasting system, channel, basin and groundwater modelling to the pilot sites. In addition water quality modelling using reactive transport models such as PhreeqC or ToughReact will be applied in water balance modelling when necessary for estimation of water quality. This includes the development of models to describe the mining environment. E.g. basin models need to be developed to calculate the geochemical reactions. The developed modelling methods may be used elsewhere in the world.
