The reasons given for the alternatives are being responsive to public comment, and a recent geotechnical survey that suggests a fault zone may cross the proposed reservoir site.  These faults were first mapped in 2007, and are currently showing on a map of faults on the United States Geological Survey website.  In their presentation, Anchor QEA emphasized the uncertainty of any fault, but said that further investigation is required before any further design work can continue. 

Dungeness Meadows is a neighborhood immediately down-gradient from the proposed reservoir.