About: http://webisa.webdatacommons.org/201277941

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Channel samples often confirm that gradational boundary and fire clay layers have high levels of mercury and other heavy metals that contaminate surface water discharged in the methane drilling and production process.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com