The GWB BE-Meuse-RWM040 “Chalk of the Geer basin”: delayed effect for nitrate in deep, old groundwater

editorial reviewed6. Clean water and sanitatio

Developing a groundwater watch list for substances of emerging concern: a European perspective

There is growing concern globally about the occurrence of anthropogenic organic contaminants in the environment, including pharmaceuticals and personal care products. This concern extends to groundwater which is a critical water resource in Europe and its protection is a priority for the European Commission and European Union (EU) Member States. Maintaining good groundwater status supports improved public health, economic growth and sustains groundwater dependant ecosystems. A range of measures have been introduced for regulating several substances that have impacted groundwater (e.g. nitrate and pesticides). However, these measures only cover a small fraction of anthropogenic substances that could pollute groundwater. Monitoring for these unregulated substances is currently very limited or not carried out at all. Therefore, a coordinated European-wide approach is needed to identify, monitor and characterise priority substances or groups of substances that have the potential to pollute groundwater. This evidence base is critical for policy development and controls on these currently unregulated substances. The European Commission highlighted this as a need during the review of the EU Groundwater Directive Annexes in 2014, when the requirement to develop a Groundwater Watch List (GWWL) was established. This paper describes the approach that has been developed through a voluntary initiative as part of the EU CIS Working Group Groundwater to establish the voluntary EU GWWL. The process for developing the GWWL is one that has brought together researchers, regulators and industry, and is described here for the first time. A summary of the key principles behind the methodology is presented as well as results from pilot studies using per- and polyfluoroalkyl substances and pharmaceuticals. These explore and support the viability of the GWWL process, an important step towards its adoption and its future use for groundwater protection across Europe

Aggregated indicators from an optimized groundwater monitoring network: example in Walloon region of Belgium for implementation of the European Water Directive

Following prescriptions of the recent European Water Framework Directive, a groundwater quality evaluation system must be adopted for checking the groundwater status with respect to different contaminants. A screening evaluation system (based on a system developed by the French Water Agencies) has been adapted to the specific conditions in the Walloon Region of Belgium. Groundwater quality data are aggregated into indicators with respect to different water uses such as drinking water standards, thresholds values for preserving dependent surface ecosystems, or the groundwater ‘natural or patrimonial state’. A global groundwater quality indicator can also be calculated. Different aggregation techniques are discussed with their respective influence on the final indicator. In relation to this evaluation, the monitoring network must be adapted for being (as far as possible) representative of the global quality of water in each groundwater body. Existing knowledge and understanding of the actual hydrogeological conditions were used in priority for choosing an adequate network of monitoring points. At the same time, the spatial density of points was checked in order to obtain a statistically representative network. Applications were performed in five different GWBodies belonging to the hydrographic district of the Meuse River in the Walloon Region and with different contrasted geological conditions: Cretaceous chalks, Carboniferous limestones and Pleistocene gravels of the alluvial plain of the River Meuse. These examples provide a good opportunity for further discussion and work about the main related issues: optimzation procedures, aggregation methods and estimation of the reliability of indicators

Terms & definitions on the identification of drinking water protected areas and related zones

This presentation defines, discusses and compares different concepts on the protection of groundwater resources and groundwater abstraction points in the scope of exchaqnges between EU DGEnv CIS working groups on Groundwater and Drinking Water, in the scope of the revision of the European Drinking Water Directive

Réseaux de surveillance des masses d’eau souterraine en Région Wallonne

La mise en œuvre de la directive européenne cadre de l’eau nécessite l’élaboration, par masse d’eau souterraine, d’un réseau de mesure et de surveillance aussi représentatif que possible de l’état des eaux souterraines. En Région Wallonne, cinq masses d’eau de caractéristiques différentes d’un point de vue géologique, hydrogéologique et d’occupation du sol ont fait l’objet d’une étude en vue d’établir une stratégie de sélection des sites de mesures. La sélection des stations de mesure composant chaque réseau a été réalisé en tenant compte de divers critères tels que la géologie, l’hydrogéologie et l’hydrochimie de la masse d’eau, les caractéristiques des points d’eau existants, mais aussi la densité et la répartition spatiale des ouvrages sélectionnés. Le système d’évaluation de la qualité des eaux souterraines SEQESO adopté en Région Wallonne a été appliqué à chacun de ces réseaux afin d’apprécier l’état chimique de ces masses d’eaux conformément à la directive-cadre. The implementation of the European water framework directive requires the construction of monitoring networks being as far as possible representative of the global water quality in each groundwater body. In Walloon Region, five groundwater bodies with different contrasted geological conditions, hydrogeological conditions and soil occupancy, were studied in order to establish an approach for choosing an adequate network of monitoring points. This selection was realized by considering different criterions as the groundwater geology, hydrogeology and hydrochemistry, the feature of existing waterpoints, but also the density and the spatial distribution of the selected points in order to obtain a statistically representative network. The quality assessment system for groundwater (SEQESO) adopted by the Walloon Region has been applied to the five monitoring networks in order to fully appreciate the chemical status of the groundwater bodies in accordance with the European directive

Treatment of allograft nonunions with recombinant human bone morphogenetic proteins (rhBMP).

Fractures and nonunions are the main complications associated with bone allografts. Although the osteogenic role of recombinant human bone morphogenetic proteins (rhBMPs) has been demonstrated in experimental models and human tibial nonunions, the results are unknown for allograft nonunions. In this study, the efficacy of rhBMPs was evaluated in nonunions of femoral allografts. The results of six allograft nonunions in five patients who underwent resection of malignant bone tumours and allograft bone transplantation were analysed one to five years following application of rhBMPs at the nonunion site. There were two osteoarticular allografts and three intercalary allografts. Of three intercalary allografts, one demonstrated nonunion at both ends. Four patients received adjuvant chemotherapy and three had additional radiation therapy. There were two allograft fracture nonunions and four nonunions at the allograft-host junction. Two allograft fracture nonunions and one nonunion at the allograft-host junction were treated with 12 mg of rhBMP-2. The remaining three nonunions were treated with 7 mg of rhBMP-7 (Osigraft). The outcome and radiological evidence of healing were evaluated at a minimal follow-up of twelve months. There was neither healing of allograft fractures nor union of allograft-host junction. There was elongation or enlargement of the callus from the host. One patient continued to develop resorption of the allograft, which led to allograft fracture. Two patients who were treated with rhBMP-7 and corticocancellous allografts developed sterile drainage. There was no tumour recurrence with the use of rhBMPs after a mean follow-up of 39+/-25 months. rhBMP's alone were not sufficient to achieve healing in allograft nonunions and fractures following wide resection including periosteum and soft tissues

Using pharmaceutical compounds as tracers of urban sources of nitrate in groundwater

Nitrate is a natural compound part of the nitrogen cycle. It is widely used in agriculture but urban waste water produced by anthropogenic activities can also constitute non-agricultural sources of nitrate. Nowadays, the significant increase of nitrate concentrations in groundwater presents a risk for human health. In order to set up adequate measures to protect water quality, it is necessary to determine the possible sources of nitrate such as fertilizers, manure or urban waste waters. Different approaches are available for such purpose based on hydrochemical and isotopic signatures but they remain relatively uncertain. Recent advances in the detection of pharmaceutical compounds at extremely low concentrations in groundwater (in the range of ng/L) offer the opportunity to use some of these substances as chemical tracers to differentiate among nitrate sources. In this context, groundwater samples were collected from public water supplies, natural sources, domestic wells and karstic springs in six different sites in the Walloon Region of Belgium. Classical inorganic chemicals, stable isotopes of nitrate and boron were measured. In addition, ten pharmaceuticals (e.g. diclofenac, carbamazepine, hydrochlorothiazide) among the most frequently detected in the region’s waters were also quantified. The use of pharmaceutical compounds as chemical markers of urban water is only in its early stages. However, the results allowed to identify the most likely sources of nitrate in cases where isotopic analyses were unable to do it. Results show that using pharmaceuticals to discriminate nitrate sources (urban or agricultural) offers interesting perspectives for the future. In particular, the use of certain substances such as carbamazepine is promising

A hydrochemical - isotopic approach for assessing factors controlling the regional pollution of an urban aquifer

The alluvial aquifer of the Meuse River is contaminated at regional scale in the urbanized and industrialized area of Liège in Belgium, in particular inorganics pollutants such as sulfate, nitrate and ammonium. The sources of those contaminants are numerous: brownfields, urban waste water, subsurface acid mine drainage from former coal mines, atmospheric deposits related to former pollutants emissions in the atmosphere ... Sulfate, nitrate and ammonium are both typical pollutants of the aquifer and tracers of the possible pollution sources. In the Water Framework Directive context, a detailed hydrogeochemical characterization of groundwater was performed. The aim is to determine the origin of the inorganic contaminations, the main processes contributing to poor groundwater quality and the spatial extent of the contaminations. A large hydrochemical sampling campaign was performed, based on 71 selected representative sampling locations, to better characterize the different vectors (end-members) of contamination of the alluvial aquifer and their respective contribution to groundwater contamination in the area. Groundwater samples were collected and analyzed for major and minor compounds and metallic trace elements. The analyses also include stable isotopes in water, sulfate, nitrate, ammonium, dissolved inorganic carbon, boron and strontium. Different hydrogeochemical approaches are combined to obtain a global understanding of the hydrogeochemical processes at regional scale. Hydrochemical interpretations are based on classical diagrams, spatial distribution maps, geochemical equations, multivariate statistics such as self-organizing maps and isotopic analyses. With this combined approach, the location of the contaminant sources and most contaminated sectors of the alluvial aquifer together with a better understanding of geochemical processes involved are obtained. Redox processes strongly influence the composition of groundwater, specifically for compounds degrading the quality of groundwater in the area (sulfate, nitrate and ammonium). The highest concentrations of sulfate can be associated with the post-mining stage in the acid mine drainage process. Various reactions involving nitrogen compounds have been identified and allow a better understanding of causes of high concentrations of ammonium and nitrate. Denitrification and sulphate reduction are also demonstrated based on isotopic ratios

Case study 2: Groundwater – surface water interaction in limestone areas of the GWB BE_Meuse_RWM021 (Belgium)

peer reviewedThe achievement of good status in groundwater bodies involves meeting a series of conditions, which are defined in the Water Framework Directive (WFD) and, in the case of good chemical status, are given further detail in the Groundwater Directive (GWD). One of these conditions is to ensure that groundwater inputs to associated surface waters do not result in failure to meet the environmental objectives of those waters or result in significant diminution in status/ecological or chemical quality of those waters. GWAAE (Groundwater Associated Aquatic Ecosystems) are those surface water bodies (SWBs), including rivers, standing waters and transitional waters where the surface water ecology and hydrology is dependent on contributions from groundwater in order to meet their environmental objectives under the WFD. These environmental objectives may vary, and therefore the associated environmental quality standards (EQS) or flow/level requirements of GWAAEs may differ between high status and good status SWBs. As noted in the Blueprint for Water, analysis of the first River Basin Management Plans has shown that Member States (MS) have experienced difficulties in understanding the interactions between groundwater and surface water and undertaking the necessary status assessments. This was highlighted in a survey carried out by Working Group Groundwater (WGGW) in 2014/15, which indicated that only half of the MS had assessed quantitative interactions and very few had addressed chemical pressures, including the derivation of threshold values (TVs) that were appropriate to the WFD objectives for GWAAEs. This report aims to further knowledge on what GWAAE are, how they are aligned to WFD processes, and support Member States to properly include the needs of these ecosystems in river basin management planning. The report clarifies the categories of GWAAE and their relative dependence on groundwater and collates current available knowledge and experience via a number of examples and case studies. Terminology and status assessment procedures are explained and pragmatic approaches are proposed which leave some flexibility for MS to adapt to their own specific needs. This technical report, which is not a "guidance document", makes use of and complements existing CIS documents, including existing technical reports on groundwater dependent terrestrial ecosystems (GWDTEs) and Guidance Document 18 (Guidance on Groundwater Status and Trend Assessment). A number of recommendations for technical users of the report are highlighted in boxes in each Chapter. The common themes from these recommendations are collated in Chapter 8, as issues and questions to WGGW and MS in general. The key message from this is the need for closer interaction between scientific disciplines, practitioners and Working Groups in developing conceptual understanding for GWAAEs and implementation of WFD requirements, including identification of GWAAEs, their characterisation and monitoring, and adopting appropriate status assessment methodologies.Caractérisation complémentaire des masses d’eau dont le bon état dépend d’interactions entre les eaux de surface et les eaux souterraine