Testimony Concerning the Vaporization of Contaminants from Soil and Groundwater into Indoor Environments and Human Exposure to Such Contaminants

Prepared for the Public Hearing New York Assembly Standing Committee on Environmental Conservation
Ithaca, NY April 21, 2005
by Tammo Steenhuis and Lawrence Cathles, Professors Cornell University

This testimony is based on the research of the class “Introduction to Ground Water” and discussion with community members and Cornell scientists. South hill is unique and a complex environment. The hillsides consists of some topsoil, soft shale and hard shale with many cracks (joints). There is not real ground water table in the shale. The valley is more typical and has an ground water table at relatively shallow depths especially during the winter. Science tells us that the pollutants will travel down the hill but cannot predict the exact paths that will be traveled. Ground penetrating radar might be the best way to find the DNAPLs such as TCE and PERC, but will not be effective in finding all the accumulations that can be in almost any crack or pocket in the bedrock. In addition the radar penetrates only a few meters. In the valley the DNAPLs will pond on the top of bedrock, but small pockets of DNAPLs will be difficult to locate.

The current testing of both ground water and indoor air quality is a good start but limited in its extent and may not define the location of all the DNAPLs. The indoor air quality can be highly variable and a 24 hour sample is not necessarily a good indication of the long term exposure.

Even if and when the extent and the severity of the pollution are defined, complete cleanup would be an unrealistic and probably undesirable goal. Digging all the soft shale below the Emerson plant would take years to accomplish, destroy the neighborhood, and would be unlikely to be effective. In Berkely, California there was a spill on a similar hillside. After spending great sums of money, the path of the TCE is pretty well known, however, the site itself is still not cleaned up.

We recommend that steps be taken to decrease the anxiety level of the home owners potentially affected and steps be taken to prevent further contamination.

Decrease anxiety of the people:

1. Each home that could be potentially affected should be mitigated with a basement ventilation system. Money is better spent on mitigation than on extensive air sampling and analysis (at approximately $1000 per sample). Few houses should be monitored to assure that the mitigation is functioning.
2. Guarantee that houses can be sold at fair market value. The differences between the actual selling price and the fair market value will be made up.
   
   Prevent further contamination:
   
3. All future spills should be prevented by cleaning up all potential sources at the Emerson plant. This will require cooperation and openness.

Tammo Steenhuis
Department of Biological and Environmental Engineering
Riley Robb Hall
Cornell University
Ithaca NY 14853
Email: TSS1@cornell.edu

Lawrence Cathles
Department of Earth and Atmospheric Sciences
Snee Hall
Cornell University
Ithaca NY 14853
Email: cathles@geology.geo.cornell.edu