Frequently Asked Questions About the Gowanus Superfund Project
The Gowanus Remediation Team, abbreviated in various materials as GRT, is the group of contractors and professionals completing the EPA mandated cleanup and environmental remediation of the Gowanus Canal.
The Gowanus Canal is a 100-foot wide, 1.8-mile-long canal in the New York City (NYC) borough of Brooklyn, Kings County, New York. The canal is bounded by several neighborhoods,
Gowanus, Carroll Gardens, and Red Hook. Cobble Hill and Boerem Hill are north and Park Slope, east of the canal. The canal begins at Butler Street, between Bond Street and Nevins Street, and empties into New York Harbor.
Formally known as the National Priorities List, The United States EPA’s Superfund program is responsible for cleaning up the nation’s contaminated land and waterways based on their ranking on the National Priorities List and responding to environmental emergencies, oil spills and natural disasters. To protect public health and the environment, the Superfund program focuses on making a visible and lasting difference in communities, ensuring that people can live and work in healthy, vibrant places.
The Gowanus Canal was built in the mid-1800s and was used as a major industrial transportation route. Many historical industries operated along the canal. In addition to the legacy industrial pollution, contamination flows into the canal from overflows from sewer systems that carry sanitary waste from homes and rainwater from storm drains. Numerous contaminants, including polycyclic aromatic hydrocarbons, polychlorinated biphenyls and heavy metals, are found at high levels in the sediment in the canal.
In April 2009, EPA proposed adding the Gowanus Canal to the National Priorities List (NPL). EPA performed field work to characterize the nature and extent of contamination in the canal; determine the human health and ecological risks from exposure to contamination in the canal; identify the sources of contamination to the canal; and determine the physical and chemical characteristics of the canal that would influence the development, evaluation and selection of cleanup alternatives. This work culminated in the development of a Remedial Investigation and Feasibility Study Report, which summarized the investigation findings and evaluated the feasibility of a range of potential remedies.
On December 27, 2012, EPA released a Proposed Remedial Action Plan (PRAP) describing its suggested remedy for the site. The PRAP recommended removing contaminated sediment that has accumulated as a result of industrial activity and sewer discharges from the bottom of the canal by dredging. In some locations, sediment would be permanently stabilized to prevent migration of contaminants. The dredged areas would then be capped. EPA also recommended controls to prevent combined sewer overflows (CSOs) and other land-based sources of contamination from compromising the cleanup.
The EPA accepted public comments regarding the Proposed Plan for a 90-day period. On January 23 and 24, 2012 EPA held public meetings to present the proposed plan and respond to questions and comments from attendees. More than 300 people attended the meetings.
After the public comment period ended the EPA issued a formal Record of Decision (ROD) selecting a remedy for the site on September 27, 2013. The Record of Decision included a Responsiveness Summary to comments and concerns received during the public comment period which were considered in the EPA’s final decision in the selection of a remedy to address the contamination at the site.
A Record of Decision (ROD), selecting a remedy for the site, was signed on September 27, 2013. The plan divides the canal into three segments, or Remediation Target Areas (RTA 1, 2 & 3). The first segment runs from the top of the canal at Butler Street to 3rd Street, the second segment from 3rd Street to just south of the Hamilton Avenue Bridge and the third segment runs from the Hamilton Avenue Bridge to the mouth of the canal. Approximately 300,000 cubic yards of contaminated sediment will be dredged from the first and second segments. For the third segment, approximately 281,000 cubic yards of contaminated sediment will be dredged. The plan also calls for removing contaminated material that was placed in the 1st Street turning basin decades ago and restoring about 475 feet of the former basin. The ROD also requires that a portion of the 5th Street turning basin underneath the 3rd Avenue bridge and extending about 25 feet to the east of the bridge be dredged and restored.
In dredged areas of the canal where contamination exists in the deeper native sediment, multiple layers of clean material will be placed to cap the contamination. The multilayer cap will consist of an “active” layer made of a specific type of clay and activated carbon that will remove contamination that could well up from below, an “isolation” layer of sand and gravel that will ensure that the contaminants are not exposed, and an “armor” layer of heavier gravel and stone to prevent erosion of the underlying layers from boat traffic and canal currents. Finally, sufficient clean sand will be placed on top of the “armor” layer to fill in the voids between the stones and to establish sufficient depth in order to restore the canal bottom as a habitat. In the middle and upper segments of the canal where the native sediment is contaminated with particular contaminants of concern, In-Situ Stabilization (ISS) will be employed (link to glossary). The stabilized areas will then be covered with the multiple layer cap as described above. The remedy relies on the control of upland sources of contamination to the canal, some of which are being addressed as an additional part of the Superfund clean-up, while others are being addressed through New York State’s Brownfields program. The ROD also calls for the construction of two CSO retention tanks in the upper canal to protect the integrity of the Superfund remedy that will be implemented in the canal.
The edges of the canal are supported by bulkheads that prevent the soil from eroding or collapsing into the waterway. In some areas, the existing bulkheads will be supported as a part of the cleanup to ensure the structural integrity of the canal banks while the dredging is taking place.
During dredging, it is common to remove other material that is not sediment from the canal bed. The vast majority of this material is usually identified as modern debris or timber. In accordance with archaeological protocols, outlined in the DRAFT Cultural Resources Plan (September 2020), items are screened from dredged material and sorted.
Those items which are of potential archaeological or local significance are cleaned and decontaminated then placed in a holding area and cataloged for archaeologist review. Please click HERE for information regarding items dredged from the canal of archaeological significance as determined by professional archaeologists and the EPA.
During the cleanup activities, a series of monitoring stations will be set up to measure and record monitor air quality, noise, vibration, movement, and water quality. Environmental monitoring data will be available online at: www.gowanussuperfund.com under the updates tab. Those items which are of potential archaeological or local significance are cleaned and decontaminated then placed in a holding area and cataloged for archaeologist review. Please visit the Cultural Resources page for information regarding items dredged from the canal of archaeological significance as determined by professional archaeologists and the EPA.
Dredging work in the canal will necessitate frequent bridge openings. Temporary traffic disruptions will occur at 3rd Street, Carroll Street, Union Street, and 9th Street during bridge openings. Extended openings of the bridges will occur during periods of heavy construction activity. Street closures are being coordinated with the New York City Department of Transportation. There are also temporary recreational boating and canoeing restrictions north of the 9th Street bridge.
As we continue to adjust to the evolving COVID-19 situation, Gowanus Remediation Team is taking the necessary steps to ensure that decisions about cleanup activities at the Gowanus Canal Superfund site are made with the health and safety of the community and site workers as the priority. Moreover, our contractors are implementing health and safety plans specific to preventing the spread of the COVID-19 virus during cleanup activities. These plans require best practices for site safety, including face covering, gloves, and other appropriate personal protective equipment for employees and visitors, including temperature checks of employees, tracking employees who might be ill or have had contact with individuals testing positive for COVID-19, and social distancing. EPA will continue to monitor site operations and Gowanus Remediation Team’s health and safety practices.
Security includes fencing to restrict access at the staging site. GRT also has 24 Hour security present on the site and has installed cameras to monitor the project work area.
The nature of this work utilizes heavy civil, marine, construction equipment and methods to facilitate the remedy. As a result, at times, there will be noise levels that will be louder than neighbors experience on a typical day. As part of our monitoring program, GRT has deployed specialized equipment to ensure safe conditions. GRT continues to monitor these levels and will make every effort to notify the community in advance of significant events.
As a result of cleanup activities of this nature, neighbors and those in the area will experience odors from time to time. The GRT is monitoring air quality throughout the course of our daily work and has in place several protocols to rapidly and thoroughly address elevated concentrations of air quality levels. Our team monitors these levels throughout the workday and is alerted to changes in concentrations detected by a series of monitors so that appropriate action can be taken.
Parking restrictions are expected to be very limited. When they do occur, GRT will make every effort to inform neighbors in advance.
Progress updates will be available online at: www.gowanussuperfund.com/project-updates
There may be changes to public access for pedestrians and motorists who wish to travel across or near the canal during construction. Frequent bridge openings are needed for Gowanus Remediation Team (GRT) vessels and private construction vessels to traverse the canal. In order for a vessel to pass a bridge, the bridge must be opened and the corresponding roadway temporarily closed. Bridges may also be closed to roadway traffic for scheduled maintenance work. These bridge openings can cause delays and detours for roadway traffic. Huntington Street, east of Smith Street, will be closed until further notice to accommodate the GRT staging area. There are restrictions on recreational boating activities as approved by the U.S. Coast Guard and local authorities.