In 1997, following the deregulation of the natural gas industry, Brooklyn Union Gas Company, which held a monopoly over natural gas supply in Brooklyn, Queens, and Staten Island for over 100 years, became Keyspan Energy Corporation.  In 2007 Keyspan was acquired for $11.8 billion by the UK based company National Grid.  With 28,000 employees, National Grid is the largest electric utility in the UK and the second largest in the US.

National Grid is the fifth largest distributor of natural gas in the United States, the largest in the Northeast, and with 6,650 megawatts of generating capacity, they are also the largest supplier of electricity in New York State.[1]  They operate an electrical distribution network that serves 4.4 million customers and a gas distribution network that services 3.4 million customers.  Their Ravenswood I, aka Big Allis, and Ravenswood II generators, located just north of the Queensboro Bridge on the Queens waterfront, produce approximately a quarter of New York City’s power.

National Grid's 10 acre Greenpoint Energy Center includes a peakshaving plant, a liquefied natural gas (LNG) storage facility, a compressed natural gas (CNG) filling station, an operations center, a warehouse facility, and a waste transfer station.  Due to widespread toxic contamination from historic manufactured gas plant operations, the property is listed as a State Superfund Site.

Peakshaving Plant
National Grid's peakshaving plant is readily identifiable by the two enormous white holding tanks which dominate the property.  Constructed in 1968 and 1971, these tanks store liquefied natural gas.[2]  (LNG, which occupies 1/600th the volume of natural gas, is produced by super cooling natural gas and placing it under high pressure).  Under normal circumstances, four pipelines bringing gas from Canada and the Gulf of Mexico supply New York City with all its natural gas.[3]  However, on the coldest days of the year, when furnaces are running full tilt, these pipelines cannot meet the city’s demand for natural gas.   By importing, liquefying, and storing natural gas when demand is slack and regasifying and distributing it when demand is high, peakshaving plants ensure that New York City has adequate natural gas supplies.  Peakshaving plants also help insulate utilities and customers from price spikes during periods of high demand.  The 316 acre ConEd Astoria Plant complex, located just west of LaGuardia Airport, is home to the city’s only other peakshaving plant.

CNG Filling Station
Also on site is a compressed natural gas filling station (CNG).  CNG is primarily used to fuel vehicles and is considered to be a cleaner burning fuel alternative to diesel and gasoline. There are over a dozen CNG stations spread across the five boroughs which mostly fuel government and business owned vehicle fleets.

Manufactured Gas, Contamination, and the Attorney General
From 1928 to 1952 Brooklyn Union and Gas operated a manufactured gas plant (MGP) at what is now National Grid's Greenpoint Energy Center.[4]  Before the advent of natural gas supplies and electrical lighting, manufactured gas was the primary fuel used by homes and businesses for heating, cooking, and lighting.[5]  By the middle of the 19th century New York City had dozens of MGPs and was the nation’s leading consumer of manufactured gas.[6]  The last of these MGPs ceased operations in 1972. [DEC Map of historic MGP locations in downstate New York, pdf 800kb]

Most manufactured gas was produced by heating coal or oil while limiting its contact with the outside air.[7]  Using this method, the coal or oil could be prevented from burning while inducing the release of volatile gases that could be captured and purified to make manufactured gas.[8]  An unwanted by-product of the manufactured gas production process was coal tar.  Coal tar is a dense reddish brown to black oily-liquid mixture of highly toxic and persistent environmental contaminants.[9]    

Some coal tar was recycled as paving or construction materials but most was simply discharged into waterways, buried in onsite pits, or allowed to slowly leak from storage tanks.[10]  Coal tar contamination has commonly been found to migrate hundreds of feet through the earth from its original source structure.  However, when groundwater comes into contact with coal tar the scope of the contamination is magnified and potential exposure pathways multiply.[11] 

In February of 2007, the Attorney General of New York, Andrew Cuomo, announced his intent to sue Keyspan (now National Grid) for contaminating the soils and groundwater of East Williamsburg and the waters and sediments of Newtown Creek with MGP related wastes.[12]  In its notice of intent to sue, the AG’s office pegged Keyspan as responsible for cleanup at three MGP related sites: the Greenpoint Energy Center, the former Equity Works MGP, and the former Scholes St. Holder.

When asked for an update regarding the cleanup at the Greenpoint Energy Center Martin Brand, Remedial Projects Manager for the NYS Department of Environmental Conservation, responded: “No remediation plan has yet been developed for the Greenpoint MGP site.  Keyspan has already conducted some limited clean-up work associated with expansion of the existing gas-storage facilities on the site, but the main body of the plant has not been fully investigated or remediated.  There is a plan proposed for additional work to stabilize the bulkhead along the shore line, which is in need of repair, and this will involve some remedial work as well.  We have received reports of coal tar in the sediments at the bottom of the Creek, but this has not been verified, and its extent (if it is indeed present) has not been established.”  For more information on the National Grid Greenpoint Energy Center Superfund Site contact Gardiner Cross at 518-402-9662 or email gwcross@gw.dec.state.ny.us

The Maspeth Holders
Many people in North Brooklyn remember this site as the host of two enormous red and white checkered tanks known as the Maspeth Holders. Constructed in 1927 and 1948, these tanks ensured constant residential gas line pressure (fluctuations in gas flows can cause pilot lights to go out, risking explosions and poisonings). The Maspeth Holders were decommissioned in the 1990's and demolished in 2001. At the time of demolition, many residents were concerned that the explosion and collapse of the tanks would release contaminants into the air.[13]

Waste Transfer Station
Keyspan operates a construction and demolition debris waste transfer station on the central western portion of the Greenpoint Energy Center.

Transfer or Disposal Destination, 2006[14]
In 2006 Keyspan Energy Delivery handled 147,453 tons of material; this sum represents 1.2% of all waste exported through transfer stations in New York City.

Material	Amount (tons)	Facility Name	Location
construction & demolition debris	20,542	New York Paving	Queens, NY
construction & demolition debris	3,130	Evergreen Recycling	Queens, NY
clean fill	48,413	Keyspan Transfer Station	Brooklyn, NY