Spatial Data Analysis
Delta-H provides a high-level spatial analysis (using GIS) of large groundwater datasets
which includes proximity analysis and identifying influencing factors on borehole
productivity such as geology, geomorphology and lineaments (e.g. dykes and faults).
The combination of multivariate statistical methods and spatial analysis of
geochemical data sets provides useful assessment of controls over water composition
and assists in the identification of possible anthropogenic influence.
Training
Delta-H staff is actively involved in the lecturing of groundwater modelling and
geochemistry courses at Universities in South Africa and Germany. We also offer
training to the public, private and mining sector.
© Delta-H Water Systems Modelling 2020
Expertise and Services
Hydrogeological Modelling
Numerical groundwater models are the best tools available to quantify groundwater
and mass balances, which can then be used to inform decision making related to
environmental impact assessments or the optimisation of engineering designs. The
project team is competent in both finite element (SPRING) and finite difference
modelling codes (Modflow, including various interfaces).
These internationally accepted modelling packages are used in a variety of applications
like numerical flow modelling to estimate mine inflow rates and associated impacts, to
define aquifer vulnerability and aquifer protection zones around abstraction boreholes
or to predict contaminant transport rates from various source types. The finite element
modelling code SPRING allows also simulating discrete fractures, undergrounding mine
workings, heat exchange as well as unsaturated flow and transport processes. For
more information on the software package SPRING visit:
Seepage Modelling
The Delta-H team is competent in developing two- and three-dimensional seepage
models for Tailings and other Mine Residue Facilities as well as contaminated soils
using the finite element software SPRING. The developed seepage models typically
consider material properties, installed drains, as well as interactions with the
underlying aquifer. The output of a three-dimensional seepage models can thereby be
coupled with regional groundwater flow and transport models to enable a realistic
representation of the entire system and inform management decisions.
Groundwater Management
Delta-H has vast experience in supporting clients with effective management and
protection of groundwater resources. Groundwater resources are subject to human
impact in many ways and the exploitation of groundwater is increasing everywhere.
Delta H provides specialist input into Environmental Impact Assessments (EIA) and
Feasibility Studies. These services include:
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Groundwater management plans
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Groundwater resource delineation (and availability assessment)
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Groundwater balance
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Aquifer characterisation
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Conceptual groundwater model development
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Cumulative groundwater impact assessment
Geochemistry
The main purpose of geochemical assessments is to predict the likely drainage and
seepage water quality associated with Mine Residue Deposits (MRD). This information
is used as inputs into groundwater flow and transport models to assess the potential
pollution plume associated with the MRD. Delta H offers mine site geochemical
investigations including Acid Rock Drainage (ARD) risk assessments and management
plans, as well as geochemical modellinge:
Hydraulic Plume Containment
The scavenger well system is designed to hydraulically control the movement of
polluted groundwater in order to prevent continued expansion of the polluted zone,
i.e. to capture and remove polluted groundwater. The implementation of a scavenger
well system is driven by a sound understanding of the migration of pollutants and
hydrogeological parameters of the groundwater flow path (conceptual model) and
supported with a site-specific numerical flow and transport model. Delta-H is
experienced in the design, implementation and management of both conventional
vertical scavenger wells as well as horizontal scavenger wells.. A single horizontal well
could in theory be more effective than a number conventional scavenger wells.
Groundwater Supply
Delta-H applies conventional geophysical survey methods as well as retrieved
knowledge of the hydrogeological setting to determine optimal drilling targets for
water supply boreholes. Delta-H have developed a respectable working relationship
with drilling contractors and pumping test teams to provide service of high quality.
With the assistance of project partners Delta-H caters for all pumping and
infrastructure requirements as well as the commissioning of water supply boreholes
and wellfields.