level

term of mine structure. 
bottom, floor, horizon

OverviewRelatedTableS1S2S3

Wikidata
storey, underground mine complex, Q116948109, ventilation level, roadway floor, 

• Google Knowledge entry^@
  

roadway floor – underground mine complex – ventilation level – 

Type	Date	Description	Keywords	Notes	Source
link		Google Knowledge entry@			Wikidata

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