Unable to build close

[KviZ]

How can I make Gold mine unable to build close to town hall?

 

[hl2.exe]

Remove the "Return gold and lumber" ability from your building (es Town Hall) then with a trigger re-add it
Es:
Event
A unit finishes a construction
Condition
unit type of constructed structure equal to *your unit type*
Action
Add Return gold and lumber to constructed structure

 

[KviZ]

Thanks