When a day of heavy rainfall forced untreated wastewater to be released from Milwaukee’s Deep Tunnel, it was the sixth time that has happened this year. Federal regulators could fine the city if it happens again. The six releases by the Milwaukee Metropolitan Sewerage District ties a record set nearly 20 years ago. Though the release Monday was legally permissible, it is possible the M-M-S-D could be fined anyway. The fine could come from the E-P-A, or the Wisconsin Department of Natural Resources.