Mining Terms - PA DEP - PAAbutment - In coal mining, (1) the weight of the rocks above a narrow roadway is .. Check curtain - Sheet of brattice cloth hung across an airway to control the passage of .. surplus ground or surface water either by artificial means or by gravity flow. ... Raise - A secondary or tertiary inclined opening, vertical or near-vertical.flow chart primary secondary and tertiary of mining,Schematic of the protocol for primary, secondary and tertiary RNAi .Schematic of the protocol for primary, secondary and tertiary RNAi screens (A) Flowchart for the chronic, primary RNAi screen over three generations. Four L4.
flow chart primary secondary and tertiary of mining