Final Addendum to the Corrective Action Investigation Plan for Corrective Action Unit 447, Project Shoal area, Nevada, Subsurface Site, Revision 1, April 1999

Chapter 6.0 in the Shoal Subsurface Corrective Action Investigation Plan (CAIP) provided a framework for a data decision analysis (DDA) that would be used to determine investigation methods and data collection methods to minimize uncertainty in groundwater flow and transport predictions. Uncertain parameters were identified and possible field activities that could provide information on those uncertain parameters were briefly described. The DDA has now been completed (Pohll and Forsgren, 1999) and prompts this addendum to describe the outcome of the DDA, how it was used to determine the next phase of data collection for the Shoal Subsurface activities, and to provide details of the planned investigations sufficient to allow understanding of the scope and completion of the tasks involved