This glossary includes definitions of terms and acronyms that are mentioned within this website and documents that appear in the document library. Glossary terms can be searched by clicking on the first letter of the term.
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- Aeration System
A system designed to add air to water. Air can be added to water by either passing air through water or passing water through air. Aeration promotes biological degradation of organic matter in water.
The varying physical characteristics–including depth, contour, sediment and shape–of the bottom of bodies of water. The bathymetry of the Gowanus varies greatly among the three reaches.
- Benthic Community
The group of organisms living at the bottom of a pond, river, lake or ocean.
A man-made structure to retain land from sliding into the waterway.
- Citizens former Manufactured Gas Plant
Former site of a Manufactured Gas Plant (MGP) built by Citizens Gas Company that produced gas used for cooking, lighting, heating and commercial purposes from the 1860’s to the early 1960’s. For more information visit www.citizensmgpsite.com.
- Clean Water Act (CWA)
A federal law passed in 1972 that establishes guidelines for water quality in the United States.
- Coal Tar
Coal tar is a brown or black liquid that is a result of coal becoming gasified or carbonized.
- Combined Sewer Overflows (CSO)
CSOs are a component of a combined sewer system, which is a single system used to collect and transport stormwater runoff and domestic and industrial sewage through the same pipe to a single treatment location. During heavy periods of rain these systems can become overwhelmed with the volume of water and must release through an overflow. These overflows are designed to discharge untreated excess water into local waterways like the Gowanus Canal.
- Community Advisory Group (CAG)
A community advisory group is made up of members of the community. The group is the liaison group between the local community and the Environmental Protection Agency (EPA), the state regulatory agencies, and other stakeholders in cleanup of a Superfund site. Learn more about the CAG for the Gowanus Canal Superfund Site at gowanuscag.org.
- Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)
- Confined Disposal Facility (CDF)
An area, often in water, that is designated as a site to contain dredged material.
- Contaminated Sediment Technical Advisory Group (CSTAG)
A technical advisory group that is part of the Environmental Protection Agency (EPA)’s Superfund process and established to monitor progress and provide technical counsel on complex aspects of a cleanup project. The group is comprised of representatives from EPA and the Army Corps of Engineers.
- Dense Non-Aqueous Phase Liquid (DNAPL)
A Non-Aqueous Phase Liquid (NAPL) that is heavier than water. These will sink to the bottom of a waterway as opposed to light non-aqueous phase liquids, like oil, that may appear as sheens on top of water.
- Dissolved Oxygen (DO)
A measurement of the oxygen that is dissolved in water and an indicator of the quality of water.
- Environmental Protection Agency (EPA)
The U.S. regulatory agency overseeing all Superfund sites, including the Gowanus Canal.
- Feasibility Study (FS)
- Flushing Tunnel
Installed in 1911 and reactivated in 1999, the flushing tunnel is a large propeller that moves water into and out of the Gowanus Canal either through a brick-lined 1.2-mile (1.9-km) tunnel via Butler Street to Buttermilk Channel (between lower Brooklyn and Governor’s Island) or through the mouth of the Canal that opens into New York Harbor.
- Fulton Municipal former Manufactured Gas Plant
Former site of the Fulton Municipal Manufactured Gas Plant (MGP) that produced gas used for cooking, lighting, heating and commercial purposes from approximately 1879 through the early 1930’s. For more information visit www.fultonmgpsite.com.
- Groundwater Upwelling
The occurrence of groundwater seeping into a body of water through the sediment on its floor.
- Hazard Ranking System (HRS)
The numeric screening system the Environmental Protection Agency (EPA) uses to place uncontrolled waste sites on the National Priorities List (NPL). The system is based on information collected from the Preliminary Assessment and site inspection to rank the relative potential of sites to pose threat to human health or the environment.
- In-Situ Stabilization (ISS)
A soil remediation process by which contaminants are rendered immobile through reactions with stabilizing compounds injected into the soil or sediment.
- Manufactured Gas Plant (MGP)
A popular energy source beginning in the 1800s, MGPs brought gas to local homes and businesses through a network of underground pipes.
- Metropolitan former Manufactured Gas Plant
Former site of the Metropolitan Manufactured Gas Plant (MGP) that produced gas used for cooking, lighting, heating and commercial purposes from approximately 1871 through the 1930’s. For more information visit www.metropolitanmgpsite.com.
- National Priorities List (NPL)
The list of hazardous waste sites that are eligible for cleanup under Superfund or the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).
- New York City Department of Environmental Protection (DEP)
New York City’s regulatory agency overseeing environmental projects within the city.
- New York State Department of Environmental Conservation (NYSDEC)
The New York State agency that oversees environmental cleanups within the state.
- Non-Aqueous Phase Liquid (NAPL)
Organic substances that are relatively insoluble in water and are less dense than water. An example is spilled oil in a waterway.
- Non-soluble liquid
A liquid that will does not readily combine with water.
- Oleophilic Clay
A modified clay specially designed to trap hydrocarbons like Non-Aqueous Phase Liquid (NAPL) through adhesion while allowing water to pass through. This material is effective in many multi-layer engineered capping applications to prevent transport of NAPLs into the water column. Commonly found bentonite or hectorite clay is altered to produce the oleophilic clay.
- Polychlorinated Biphenyls (PCBs)
Polychlorinated biphenyls have a range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids. PCBs were used in hundreds of industrial and commercial applications including electrical, heat transfer and hydraulic equipment; as plasticizers in paints, plastics and rubber products; in pigments, dyes and carbonless copy paper; and many other industrial applications.
- Polycyclic Aromatic Hydrocarbons (PAHs)
These organic chemicals are formed during the incomplete burning of coal, oil and gas, garbage, or other organic substances. They are found in Coal Tar, crude oil, creosote and roofing tar and are common in areas with high rates of development and motor vehicle traffic.
- Potentially Responsible Parties (PRPs)
Parties that may have contributed waste to the site. The Environmental Protection Agency (EPA) uses document reviews, site investigations, interviews, information supplied in response to information request letters, and title searches to determine a party’s liability for cleanup at a Superfund site.
- Preliminary Assessment
The process used by the Environmental Protection Agency (EPA) based on readily available information to determine if a particular site poses any threat to human health or the environment. It also makes recommendations where appropriate about possible further investigation or evaluation for corrective actions. See preliminary assessment section.
- Proposed Remedial Action Plan (PRAP)
A study of alternatives considered for remediation of a hazardous waste site and the rationale for selecting a recommended alternative. The PRAP is based on the site’s Remedial Investigation (RI) and Feasibility Study (FS). The PRAP is reviewed by the public, state agencies, and other parties. See PRAP section.
- Purifier Waste
A waste product derived from the production of manufactured gas. It looks like dark blue wood chips and has a strong burnt odor.
- Record of Decision (ROD)
A public document that explains which alternatives will be used for remediation of a hazardous waste site. The ROD is based on the Proposed Remedial Action Plan (PRAP) and comments on the PRAP from the public. See Record of Decision section.
- Remedial Action (RA)
- Remedial Design (RD)
- Remedial Investigation (RI)
A phase in the Superfund process done in conjunction with the Feasibility Study (FS). This investigation characterizes site conditions, determines the nature of the waste at the site, assesses the threat to health and the environment and evaluates the performance and cost of different cleanup remedies.
Solid materials, such as dirt, minerals or rocks, that settle at the bottom of a body of water.
- Semivolatile Organic Compounds (SVOCs)
Closely related to VOCs, these compounds change to gas very slowly at a standard temperature.
The federal government’s program, overseen by the Environmental Protection Agency (EPA), to clean up the nation’s uncontrolled hazardous waste sites. See the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).
- Volatile Organic Compounds (VOCs)
Organic compounds that can become a gas at room temperature. VOCs are the leading cause of ground-level ozone. Common sources which may emit VOCs into the air include housekeeping and maintenance products; paints, coatings, and inks; and building and furnishing materials.