INTRODUCTION
The recent implementation of European Water Framework Directive
(2000/60/CE) integrates water resources availability, management,
sustainability criteria and water protection. Under these
considerations, River Basin District Agencies and competent government
authorities of Member States have to redirect the water policies and as
a consequence, projects carried out by private companies have to be
adapted. Specifically, this Directive aims to identify where and to
what extend human activities may be placing the achievement of the
Directive’s environmental objectives and the achievement of a good
ecological, chemical and quantitative water status. As a consequence,
management criteria have to be applied as a key for the identification,
characterisation and status analysis of water bodies. This includes the
identification of impacts of human activities over the quality and
quantity of water resources, the analysis of water contaminants and the
characterisation of their source term. Related to pollution, the
Directive indicates that reversal of significant increasing trends in
the concentration of any pollution in groundwater has to be achieved
and inputs into groundwater limited. These requirements will have
direct implications in the orientation of environmental consultancy
projects and at the same time they will open new opportunities of work
in the fields of water management studies, environmental resources
planning, use of new characterisation methodologies and alternative
remediation techniques.
REAL CASES
The objective of this paper is to show the applicability of new
methodologies under the sustainability considerations described in the
European Water Framework. Four real cases carried out by Enviros-Spain
which fulfil the most exigent environmental demands are detailed. Their
description is focussed in characterisation works, strategies design,
aquifer quality recovery, use of numerical models as key tools for
groundwater management, coastal aquifers remediation, and development
of SIG for planning and decision support systems, human impacts
analysis and the assessment of risks to the achievement environmental
objectives before 2015.
a d v e r t i s e m e n t
Case 1. Strategies for
characterisation and aquifer remediation
In an alluvial aquifer where a contamination event by chlorinated
organic solvent was detected, different characterisation and
remediation techniques were carried out. In the preliminary phase the
source term was identified and the soil properties were described.
Afterwards, traditional decontamination methods were applied (pump and
treat and soil vapour extraction) which were not able to bring out
satisfactory results (Figure 1), only the spill was limited and
concentration trends were reversed but levels indicated in the
Directive were not attained. As a consequence, alternative methods were
projected in the next remediation phase. On the one hand, laboratory
experiments were performed to evaluate the effectiveness of the
installation of a permeable reactive barrier (of zero valent iron); and
on the other hand an in situ chemical oxidation test was carried out in
which potassium permanganate was injected. Both experiments were
considered successful as pollution load was almost eliminated during
the test period. Finally, to corroborate and to quantify the conceptual
model, the experiments were simulated and reproduced with reactive
transport models. Additionally, the aquifer system was also modelled
taking into consideration the natural degradation by reductive
dechlorination using the simultaneous transport problems approach.
Case 2. Characterisation, remediation and groundwater
management in coastal aquifers
A quantitative preliminary study of strategic coastal alluvial was
accomplished considering its importance either by large amount of
available resources and by the implication of several user types.
Different hypothetic scenarios of aquifer exploitation were simulated
for the further 20 years, developing a 3D flow and transport model with
variable density (Figure 2). With this model, a large area of about 15
x 5 km was reproduced and vertical salinity profiles were used for its
calibration. The aim of this study was to optimize groundwater
management including the promotion of the best practices in good water
status, different demand agents and their respective economic purposes
as well as limiting saline intrusion, in order to follow the European
Water Framework Directive. The different modelled scenarios considered
new redistributions of exploitation rates, the inclusion of hydraulic
barriers either positive (treated wastewater injection) and negative
(extraction to supply a desalinization plant). The development of these
numerical models allowed to evaluate the most sustainable option in
management terms and to choose the best emplacement and configuration
for the desalinization plan which is currently working.
Case 3. Risks identification and characterisation in
polluted environments: example of a mine tailing
In an abandoned mine tailing wastes with high As contents, the risk
of reaching and affecting groundwater was evaluated developing a
numerical model of hydrodynamic and geochemical waste evolution.
Specifically, their infiltration capacity was identified, their
chemical stability was evaluated and the future evolution of the water
chemical composition (upstream and downstream of the mine tailings) was
reproduced (Figure 3).
The numerical model results were validated with field measurements and
successfully used for assessment purposes. Following the European Water
Framework requirements, investigation results of risk assessment were
incorporated in decision making plans, natural resources were protected
and contaminants input in groundwater were limited.
Case 4. Use of Geographical Information Systems (GIS) for
data acquisition and management and as a decision support system
Enviros-Spain, as a coordinator of the implementation of European
Water Framework Directive in Catalunya under the direction of Water
Catalan Agency, has developed a SIG to considerate and to integrate all
“pressures” related to anthropogenic activities than influence or can
influence the quality and quantity of groundwater resources. This tool
has also included the projection of all actual and potential impacts
supported by a database continuously updated with new information
related to characterization and remediation tasks on going. This
information is integrated mapped in the groundwater bodies identified
(Figure 4) allowing to evaluate all factors including pressures and
impacts, for finally identifying the risk of the achievement of the
Directive’s environmental objectives. Simultaneously at the development
of this decision support tool, a methodology to calculate and to weigh
up all pressures has been elaborated and the aspects that need further
researched for improving the management plans have been identified. In
this experience, the use of GIS has proved to be a Powerful tool to
include and to work with all Water Framework Directive requirements
coupling the problems planning and the management strategy as well as
an easy and public access to environmental information.
CONCLUSIONS
The new approaches and considerations that will have to be
incorporated in some consultancy projects under the Water Framework
Directive requirements have been introduced. Special focus has been
done in water resources management and groundwater remediation and
protection because these concepts are included in first phase Directive
implementation. The direct implications are that a higher
specialization degree in different project tasks will be necessary and
a multidisciplinary approach is already proved to be indispensable. It
is desirable that these good practices will improve the water resources
availability both in quality and in quantity.
AKNOWLEDGMENTS
The experiences showed in this paper belong to projects undertook by
the Water Catalan Agency, Waste Catalan Agency (both in Spain) and the
French National Institute for Risk and Industrial Environment
(INERIS). Enviros-Spain S.L. technical staff has been involved in
many respects in this article, as well as the respective project
managers.
