Their water has become discolored, foul-smelling, or even flammable because <e1>methane</e1> from disturbed gas deposits has migrated into water <e2>wells</e2>.
Their water has become
Their water has become discolored, foul-smelling, or even flammable because methane from disturbed gas deposits has migrated into water wells.
<triplet> methane <subject> wells <object> Entity-Destination(e1,e2)