Phase 1 Certification Units (Rogers Island Area)
Phase 1 Certification Units (Rogers Island Area)

Phase 1 Certification Units (Griffin Island Area)
Phase 1 Certification Units (Griffin Island Area)

Residuals / Activities Update

Goal of the Standard

The residual standard is designed to detect and manage small amounts of contaminated sediments that may remain on the river bottom after dredging.

How the Standard Works

  • Identification of “Certification Units” of approximately 5 acres in size (see maps).
  • Collection of 40 sediment cores from within a certification unit after dredging and analyzing them for PCB concentrations.

Possible Actions

  • Lower concentrations might call for backfilling, where appropriate.
  • Higher concentrations would call for actions such as redredging or constructing a cap.

See right and below for maps of the Phase 1 certification units and for certification unit status and activities.

* All dredging-related activities have been completed for the season

Status as of:

Certification Unit Status / Activity
Unit 1 No Activity
Unit 2 No Activity
Unit 3 No Activity
Unit 4 No Activity
Unit 5 No Activity
Unit 6 No Activity
Unit 7 No Activity
Unit 8 No Activity
Unit 9 No Activity
Unit 10 No Activity
Unit 11 No Activity
Unit 12 No Activity
Unit 13 No Activity
Unit 14 No Activity
Unit 15 No Activity
Unit 16 No Activity
Unit 17 No Activity
Unit 18 No Activity
EPA