One of the core tenets of ONTAP and WAFL is guaranteed consistency on disk. No chkdsk or fsck on boot is required.
if you have FC or iSCSI luns mounted on hosts, and those hosts have not flushed their filesystems, those filesystems could require chkdsk or fsck from those hosts for those LUNs, since consistency of the filesystems in those LUNS is the responsibility of the hosts in these cases, not NetApp.