A Note from Larry Smith at Vermont Yankee

March 4, 2010

Vermont Yankee engineers and technicians continue their investigation into the source of tritium in the plant's groundwater. The Vermont Department of Health and Nuclear Regulatory Commission personnel are at Vermont Yankee monitoring the investigation.

The removal of two concrete blocks at the junction of the AOG pipe tunnel and the OG-100 drain line connection to allow for Remote Operated Vehicle (ROV) inspection of the tunnel is in progress. Preliminary staging for two ROVs to conduct the tunnel inspection is also in progress, with completion of the ROV inspection expected tomorrow. The ROVs will provide a visual inspection of conditions inside the tunnel.

Ongoing engineering activities include pipe identification and locations where guided wave technology can be used to inspect piping; Ultrasonic testing, (the use of high frequency sounds waves similar to sonar waves) and other inspection options to confirm the integrity of the Condensate Storage Tank; and the installation of two new monitoring wells. One well is to be located between GZ-10 and GZ-7, very near the CST. The second well will be located between the Containment access Building and the Construction Office Building. Down hole geo-physics testing of six monitoring wells continues and will be completed later this week. The purpose of this testing is to determine the structure of the bedrock and will help engineers and hydrology experts to better understand how groundwater flows beneath the site.

While this investigation continues, it is important to note that there has been no detectable tritium levels found in any samples taken from drinking water wells or the river.

For more details on the tritium investigation, the Vermont Department of Health has a thorough status report on the investigation at this web link: http://healthvermont.gov/enviro/rad/yankee/tritium.aspx