Every building does not need a rebuild mine method.

src/engine/gameManager/BuildingManager.java

@@ -851,4 +851,15 @@ public enum BuildingManager {
         }
 
     }
+
+    public static void rebuildMine(Building mineBuilding) {
+        mineBuilding.setRank(1);
+        mineBuilding.meshUUID = mineBuilding.getBlueprint().getMeshForRank(mineBuilding.rank);
+
+        // New rank mean new max hit points.
+
+        mineBuilding.healthMax = mineBuilding.getBlueprint().getMaxHealth(mineBuilding.rank);
+        mineBuilding.setCurrentHitPoints(mineBuilding.healthMax);
+        mineBuilding.getBounds().setBounds(mineBuilding);
+    }
 }