Officials: Sewage Treatment Disks Wash Up In Revere, Nahant

HOOKSETT, NH (CBS) – Some of the plastic discs that spilled out of a Hooksett, NH sewage treatment plant have made it as far south as Revere and Nahant.

Environmental officials offered an update Monday on the situation.

In all, an estimated 8-million of those disks overflowed into the Merrimack River. Many of them have washed up on shore in 16 different communities.

The overflow happened because of a malfunction at the plant.

Officials have tested the disks for the presence of bacteria. Some came back positive, but not at a level that's considered a threat.

Clean-up continues, with Clean Harbors working along the Merrimack in addition to 60 DCR workers scouring area beaches.

The town of Hooksett has assumed responsibility for cleanup and costs. So far there's no estimate on what that price tag may be.