CREATE TABLE table_17798 ("Year" FLOAT, "Road Opened" TEXT, "Road Closed" TEXT, "Freight Carried s Tonne" FLOAT, "Super B Capacity Reached [ citation needed ]" TEXT, "Number of Truck Loads North" FLOAT)

When was the super b capacity reached when the freight carried s tonne was 198818?
SELECT "Super B Capacity Reached [ citation needed ]" FROM table_17798 WHERE "Freight Carried s Tonne" = '198818'
SELECT "Super B Capacity Reached [ citation needed ]" FROM "table_17798" WHERE "Freight Carried s Tonne" = '198818'