FTB Inventions includes Aroma1997's Dimensional World mod.  This allows you to create a portal to a flat mining world perfect for automated mining devices like Quarries.  This world is optional to use and uses the same oregen as the overworld.  It is very useful on servers and even single player by saving your overworld from quarry holes and other similar destruction from automated mining.

Contrust a portal out of "Portal Frame" blocks five blocks high by four blocks wide.  Simply light the portal with a "Mining Multitool" and sneak while entering the portal.  This will TP you to the Mining world at the same coordinates you made the portal in the overworld, thus allowing every player to have their own portal to the mining world at their base.

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