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<http://webisa.webdatacommons.org/28720699>	<http://www.w3.org/ns/prov#value>	"Lead, arsenic, cadmium and other heavy metals are associated with coal mining and/or coal burning operations as they are natural constituents of coal and of the earth???s crust." .
<http://webisa.webdatacommons.org/28720699>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<confex.com> .
<http://webisa.webdatacommons.org/28720699>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/prov/37730807>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/28720699> .