A Note from Larry Smith at Vermont Yankee

March 3, 2010

Vermont Yankee engineers and technicians continue their investigation into the source of tritium in the plant's groundwater.

Planning continues to remove concrete blocks at the junction of the tunnel and the OG-100 drainline connection to allow for Remote Operated Vehicle (ROV) inspection of the tunnel. The inspection is designed to provide a visual inspection of conditions inside the tunnel. Block removal is scheduled for tomorrow with ROV inspection to follow.

Engineering is also continuing plans to identify pipe and locations where guided wave technology can be used to inspect piping. Ultrasonic testing, (the use of high frequency sound waves similar to sonar waves) of the bottom of the Condensate Storage Tank to confirm its integrity is planned for early next week.

The Vermont Department of Health and Nuclear Regulatory Commission personnel are at Vermont Yankee and are monitoring the investigation.

Tritium concentration monitoring is ongoing. Planning continues for the drilling 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

Also helpful is the Nuclear Regulatory Commission web page on tritium monitoring: http://www.nrc.gov/reactors/operating/ops-experience/grndwtr-contam-tritium.html