Environment DEC
From the April 2009 issue
New York's Chemical Vapor Program Called the Most "Proactive" in the Nation
In 2005, New York State decided to do something few other jurisdictions had yet considered. It decided to reopen hundreds of pollution cases to determine whether new science could shed light on old cleanups. The state took on the task of tracking down whether chemical vapors were lingering at these sites and posing threats to public health.
Four-hundred and Counting
Three years later, DEC has made significant progress in tracking down and evaluating more than 400 sites around the state. As a result, a leading vapor-intrusion watchdog has called New York's program the "most systematic and proactive" in the nation.
The former IBM facility in Endicott, NY is one of 19 sites requiring remediation for contamination.
As it embarked on the initiative, New York targeted 421 sites to check for chemical vapors. Since then, investigations have been launched at all of them. So far, 147 investigations have been completed. Of those, the state has found: 19 requiring ventilation systems to alleviate vapors discovered on-site or in neighboring buildings; 46 requiring monitoring only, and 82 needing no further action (vapor levels did not trigger the need for either ventilation or monitoring). In addition, ventilation has been determined to be necessary at 11 sites where investigations are still ongoing.
Praise from a Watchdog
"Of all the states and (U.S.) Environmental Protection Agency regions, New York has the most systematic and proactive program for identifying and addressing vapor-intrusion sites," said Lenny Siegel, Executive Director, Center for Public Environmental Oversight (see "Related Links" below), a group that has monitored vapor intrusion sites around the country.
"Vapor intrusion is an issue that wasn't even on the environmental map a generation ago," DEC Commissioner Pete Grannis said. "But as the science has developed, New York has put together an aggressive and methodical plan for addressing potential vapor-intrusion sites. More work needs to be done and the state remains committed to attacking this issue." In addition, Grannis pointed out that DEC now investigates for vapor intrusion as a regular part of its remediation projects.
What is Vapor Intrusion?
"Vapor intrusion" refers to the process by which volatile chemicals move from a source below the ground surface (such as contaminated groundwater or contaminated soil) into the indoor air of overlying or adjacent buildings. Over the last decade, science about vapor intrusion has developed dramatically.
Vapors migrate from contaminated soil or groundwater, entering buildings through gaps in the foundation or where pipes or other utilities enter the basement.
Vapors can enter buildings in two different ways. In rare cases, vapor intrusion is the result of groundwater contamination which enters basements and releases volatile chemicals into the indoor air. In most cases, vapor intrusion is caused by vapors from contaminated materials migrating through the soil directly into basements or foundation slabs.
DEC and the Department of Health (DOH) developed a joint strategy to evaluate the vapor intrusion pathway at all of the remedial sites that had been previously addressed through the Superfund, brownfields or other cleanup programs in the state. That strategy generated the list of 421 sites to be investigated. It should be noted that the 421 sites do not necessarily represent a confirmed vapor concern. Rather, New York State proactively decided to go back and review these sites to determine if there was a vapor concern.
For sites where mitigation is needed, this generally means installing a ventilation system inside buildings to move vapors to the outside where they disperse and are no longer a concern. This has occurred at 30 sites total (19 completed investigations, 11 ongoing).
More Information
For more information, visit DEC's Vapor Intrusion Guidance web page. Also see "Related Links" below. A list of the vapor intrusion investigation sites is available on DEC's website at the Status of Vapor Intrusion Evaluations at Legacy Sites web page.
Related Links:
Center for Public Environmental Oversight (leaving DEC's site)
NYSDOH Soil Vapor Intrusion (leaving DEC's site)
