Assertion: methane | /r/CreatedBy | decomposing matter
Facets:
value: at landfill sites
type: LOCATION
value: at some rubbish tips
type: LOCATION
Source sentences:
text: For years, methane produced by decomposing matter at some rubbish tips or landfill sites has been tapped as a source of gas, and used to produce electricity, heat buildings and power vehicles.