You do not need a mill for bulk sampling but depending upon reserves established, how much you take out yearly and of course available time at the nearby mill (and what they charge) Noront may well at some point find an on site mill to be economical. Maybe a lot of savings over trucking and supervising at nearby mill.
Noront will not have a good idea of reserves until ramp is finished and a lot of underground drilling is done. Windfall could have a lot more reserves yet to be found.
It seems Windfall gets little respect from new investors or analysts so proving up reserves means less to me that production putting cash in the bank to fund exploration and proving up 'ROF'.
**Seen a lot of funny things go on in the mining business. It's always best if a company does as much as they can 'in house'. All kinds of games can be played during millling even with company supervsion.