Title:
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Developments in evaluating environmental impact from utilizationof bulk inert wastes using laboratory leaching tests and field
verification : international symposium on bulk
"inert" wastes: an opportunity for use, September 1995, Leeds
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Author(s):
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Published by:
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Publication date:
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ECN
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1995
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ECN report number:
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Document type:
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ECN-RX--95-056
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Other
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Number of pages:
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Full text:
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34
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Download PDF
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Abstract:
In recent years leaching tests for construction materials and wastes havebeen developed with emphasis on using them as prediction tools for release in
the long term rather than on using them as arbitrary pass/fail tests. In the
first stages of development, the mechanisms of release and release
controlling parameters have been assessed. For each of these aspects leaching
tests have been selected, developed and in part standardized. Not all
relevant aspects of leaching are covered yet. The reducing properties of
materials, for example, are still not taken into account properly. The need
for more elaborate tests is increasing as the policy to reuse waste materials
in construction is expanding. As a consequence, the desire to improve
material quality is increasing as well. For this purpose more detailed
knowledge on the chemical speciation of contaminants is needed, as a
treatment of waste carried out to reduce a few contaminants with too high
leach rates may lead to an undesired increase in the release of other
contaminants, which were previously not a problem. Tests focussed on two main
aspects of leaching can be identified: release as a function of time, and
release as a function of main leaching controlling parameters such as pH,
redox and complexation. The relation between these tests and the data
interpretation associated with them is discussed. Another distinction in the
use of tests is related to the level of understanding needed. In CEN TC 292
tests have been distinguished in: characterization tests, compliance tests,
and on-site verification tests. An important aspect of the new development of
tests with release prediction capabilities is the verification of such
predictions in the field. Some first examples of the relation between
predictions of release from laboratory test data and field observations will
be presented: release from MSWI bottom ash monofills, and release from
road-base application of coal fly ash and MSWI bottom ash. Finally, recent
developments in EC DG12 Standard, Measurements and Testing Programme and CEN
TC 292 Characterization of Wastes are addressed. 11 figs., 2 tabs., 50 refs.
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