Evaluation of brine discharge to rivers and streams: Methodology of rapid impact assessment

Abstract

a b s t r a c tInduced by a brine discharge study for a submerse gas storage cavern project, a suitable methodology for rapid impact assessment had to be found. In this paper a simple stochastic, stationary model is described for assessment of intensity and temporal variability of chloride pollution at the regional scale of the rivershed. Chloride concentration is used as a proxy of salinity. It is assumed to be the result of deterministic process (flow-dependent) and stochastic variation (estimated for boundary conditions and tributaries by an additive error term based on PERT distribution). This approach is suited to conduct Monte Carlo simulations in order to calculate long-time means and percentiles of the prospective in-stream chloride concentration (exposure model). The biocoenoses exposed to this pollution has to be evaluated in terms of chloride tolerance. Herefore Maximum Field Distributions (MFD) of relevant species (aquatic macrophytes, macroinvertebrates, fish) were compiled and merged to Species Sensitivity Distributions (SSDs). Critical aspects of MFD data quality are discussed. Chloride model simulations representing different discharge scenarios provide exposure parameters (e.g. 90th percentile) that can be compared with SSDderived protection levels (e.g. maximum loss of 10% of taxa) to quantify and evaluate possible adverse effects as well as potential recolonisation in case of load removal. Crosslinks to conservation issues are relevant in the selection and position of rare or protected species in the SSD. As an analysis of the German legal framework and technical guidelines revealed lack of guidance and best practices for such assessment and impact evaluation, recent experience highlights serious needs in applied research.

Impact of potash mining in streams: the Llobregat basin (northeast Spain) as a case study

“…These findings align with those of previous studies, which reported that biological quality of salt polluted streams can be affected by conductivities as low as 1.5 mS cm -1 (Dunlop et al, 2005;Hart et al, 1991;Horrigan et al, 2005;Kefford et al, 2011), or even lower (Cormier et al, 2013;Kefford et al, 2011). Anyhow, the damage to the aquatic invertebrate community can be expected to increase with increasing conductivity (Berezina, 2003;Böhme, 2011;Braukmann and Böhme, 2011;Cañedo-Argüelles et al, 2012;Hart et al, 1991;Horrigan et al, 2005;Pinder et al, 2005;Piscart, 2005;Williams et al, 1999). It is important to notice the reduction in EPT taxa at sites P3 and P4, and IMMi-L, Iberian Mediterranean Multimetric Index, using qualitative data (Munné and Prat, 2009); IMMi-T, Iberian Mediterranean Multimetric Index, using quantitative data (Munné and Prat, 2009).…”

Salinization effects on coastal ecosystems: a terrestrial model ecosystem approach

“…The maximum conductivity value in soil observed in the effects phase was 1628 mS cm 21 , and freshwater bodies are not supposed to be affected by salt leaching up to 1000 mS cm 21 . Nevertheless, negative effects on less tolerant aquatic communities have previously been observed [58][59][60][61], with a change in the community structure (substitution of the less tolerant taxa to more tolerant) [62,63].…”

Modeling the Impact of Salinity Variations on Aquatic Environments: Including Negative and Positive Effects in Life Cycle Assessment

“…Climate change is altering the biogeochemical cycles on the planet and shifting water temperature, pH, dissolved oxygen concentration, and salinity . In fact, direct relationships between anthropogenic CO 2 release and alterations in the water cycle, which result in salinity variations, have been already established. − Other direct human activities, such as irrigation, , industrialization and agricultural expansion, effluent disposal, , or dam management, are also behind these salinity variations. These changes and their effects can be even more important in transitional waterbodies, such as estuaries, deltas, or coastal lagoons, which constitute less than 5% of the brackish areas worldwide but provide about half of the global fish catch …”