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From John Meersman, Environmental Restoration Division Manager |
Protecting Long Island's groundwater continues to be a top priority at Brookhaven National Laboratory. In support of this priority, the Laboratory has maintained a program to monitor groundwater quality and rapidly address any problems that arise. I would like to tell you about two recent examples of this program's effectiveness.
Monitoring detects tritium
The first example was identified by routine groundwater monitoring that Brookhaven conducts throughout the site. In February 1998, a monitoring well near the Brookhaven Linac Isotope Producer (BLIP) detected elevated levels of tritium and sodium-22. Additional soil and groundwater samples confirmed the presence of these contaminants. On- and off-site drinking water were not affected.
The BLIP facility is a national resource for producing radioactive isotopes that are crucial to nuclear medicine for both research and clinical use. Routine BLIP operations generate particles called neutrons that pass through the soil beneath the BLIP building. These neutrons "activate" the soil by reacting with atoms already present in the soil to form radioactive elements.
As reported in the June 1999 cleanupdate, Brookhaven has taken a number of steps to address this area and prevent additional groundwater contamination. In 1999, the Laboratory re-routed rainwater downspouts on the BLIP building and placed a "cap" over the area of activated soil. Both actions prevent rainwater from entering the soil and moving contaminants into the groundwater.
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| Workers conducted several test injections of silicon grout outside of the BLIP building. To encapsulate the contaminated soil, grout was injected via holes drilled through the floor from inside the building. |
In May and June of this year, the Laboratory completed its groundwater protection activities at BLIP by injecting silicon grout into the area of activated soil. This grout, which solidifies over the course of a few hours, "locks" contaminants in place so that they can't migrate into the groundwater.
Enhanced monitoring succeeds
The second example also was identified through routine groundwater monitoring. In 1999, as part of the Laboratory's enhanced groundwater protection program, 84 new groundwater monitoring wells were installed near active facilities.
Last November, a testing laboratory reported detecting tritium in a groundwater sample taken in October near one of these facilities, the g-2 (pronounced "gee minus two") experiment. Sampling determined that tritium above the drinking water standard extended 250 feet from the g-2 experiment. This tritium was also created by soil activation. On- and off-site drinking water were not affected.
When the tritium detection was confirmed, the Laboratory told the community and regulators. Also, extensive sampling was done to define the extent of the contamination.
The Laboratory has now "capped" this area to prevent rainwater from percolating through the contaminated soil. Also, the g-2 experiment has been re-designed to reduce soil activation. Continued groundwater monitoring will be used to assess the effectiveness of these actions. More information is available at www.esh.bnl.gov/esd/gw.htm.
Efforts continue
These two examples illustrate the effectiveness of the Laboratory's groundwater protection program for early identification of potential hazards. Brookhaven is continuing to work hard to control or eliminate potential sources of groundwater contamination in order to protect Long Island's sole-source aquifer.
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| The silicon grout injections form "bulbs" at several depths to encapsulate the contaminated soil. Above, the corncob-like area shows the final placement of the grout. The blocks at top and left and the central column show existing portions of the BLIP building. |