Gowanus Canal Water Quality Summit, Session 2

The Gowanus Canal Water Quality Summit is intended to inspire dialog among participants concerning a variety of issues related to the canal’s water quality. The summit will consist of a series of four evening workshops, during which there will be 2 or 3 presentations, followed by discussion. Speakers will address issues such as contaminated sediments, sewer infrastructure, land use, green district planning and other related factors. The summit will culminate with a "Green Gowanus charette" - a participatory visioning workshop during which participants will have an opportunity to translate their ideas into a set of working recommendations.

Session 2: Causes & Potential Solutions to Water Quality Problems
March 6, 2007

Combined Sewer Overflows: Centralized and Decentralized Solutions

This session will cover the number of overflow events that occur from the 16 existing combined
sewage outfalls (CSOs) on the canal. Topics will include a description of the CSO-sheds and regu-
lators associated with each, a discussion of the existing threshold capacity of each regulator to avoid
CSOs and an overview of modeling efforts undertaken to date. The session will then focus on some
proposed solutions to the problem of CSOs in the Canal, including a centralized approach involv-
ing NYCDEP capital projects and a decentralized low-impact development approach.

Contaminated Sediments: Dredging, Disposal, Scrubbing or Reuse

This session will focus on the spatial distribution of contaminated sediments on the floor of the
Gowanus Canal and will provide a comparison to sediments elsewhere in the New York/New
Jersey Harbor Estuary. The sources of contaminated sediments, and known and potential mech-
anisms of mobilization of contaminated sediments into the water column will be described. The
session will then introduce solutions, such as the dredging and disposal of sediments and the
dredging and reuse or cleaning of contaminated sediments.

Contaminated Groundwater

This session will describe the type of contaminants that are or could be entering the canal from
riparian aquifers, focusing on recent findings of groundwater contamination in the Ikea and
Whole Foods sites and mechanisms of transport of contaminated groundwater into the canal.
Solutions to this issue will also be discussed, including pump and treat remediation of
groundwater and the complete removal of contaminated soils.

All sessions run from 6:30 p.m. to 9:00 p.m. and will be located at Polytechnic University;
Dibner Library, Room LC 400; 333 Jay Street, Brooklyn. Pleae visit www.poly.edu/directions for directions.

Mr. Keith Mahoney; New York City Department of Environmental Protection
Mr. Susan McCormick; New York State Department of Environmental Conservation
Dr. Franco Montalto; eDesign and Gowanus Canal CDC
Dr. Keith Jones; Brookhaven National Laboratory
Dr. Patricia Culligan; Columbia University
Mr. Eric Stern*; United States EnvironmentalProtection Agency
Mr. Al Wilshire; Keyspan

Speaker not confirmed.
Speakers, subjects, locations and
dates are subject to change.
Please check our website as the
date of each session approaches