Con Edison: public issues - manufactured gas plants

manufactured gas plants

Con Edison is working closely with state and local environmental and health officials to test and remediate, where appropriate, sites that many years ago were once home to Manufactured Gas Plants (MGPs). These plants represented the cutting edge of 19th century technology -- existing from the early 1800s to mid 1900s -- needed to heat homes and businesses, and light our city’s streetlamps. Though MGPs are largely credited with helping drive the Industrial Revolution, their legacy is mixed.

Circa 1890. The gas works and storage tanks of the Metropolitan Gas Light Company, predecessor of the Consolidated Gas Company of New York and subsequently Con Edison.

Developed before the creation of natural gas systems, manufactured gas plants used whale oil, rosin, coal, or a mixture of coal, oil, and water to produce a gas that could be distributed and used as fuel. However, some of the byproducts of gas production, such as coal tar (oily waste containing volatile and non-volatile chemicals) are potentially hazardous to human health and the environment.

An estimated 5,000 former manufactured gas plants sites exist across the country, with approximately 250 of these in New York State. Several of these New York sites are on properties owned or formerly owned by Con Edison or its predecessor companies. Like other utilities across the country, Con Edison is working with state and local officials to identify and test sites in our service territory. To ensure that information about the condition of these sites becomes available quickly, Con Edison is offering to perform environmental screenings before the formal and more lengthy investigation process begins for them.

A primary goal of these investigations is to evaluate actual and potential risks to the public through exposure to contaminants from these facilities. Exposure to contaminants can potentially occur through direct contact with the waste or through gaseous contaminants getting into indoor air. Exposure to contaminated groundwater through ingestion is not expected because the areas around these sites are served by municipal water systems. Because these sites have been closed for many years and, in most cases redeveloped, we do not anticipate exposures to be significant. If residual substances or byproducts from the gas-making process are present on a site much of the waste or contaminated soil will not be at the surface where direct contact exposure may occur. Con Edison and agency staff are preparing a soil gas/indoor air survey work plan that will be used at sites where testing is warranted or is requested by the property owner.

Con Edison will expedite the testing and remediation, working with experienced, independent experts as well as state and local agencies. We will also take effective, reasonable, and prompt action to address any concerns of residents and business owners who may be affected. In fact, testing and remediation is already underway at several former MGP sites.

If you would like more information about MGPs, please call our toll-free information and response line, (877)602-6633.

Additional information is also available in the MGP FAQ, and the MGP Fact Sheet (PDF format) prepared by Con Edison, the New York State Department of Environmental Conservation, and the New York State Department of Health.