PG&E OFFSHORE CENTRAL COASTAL CALIFORNIA SEISMIC IMAGING PROJECT Public Scoping Meeting California State Lands Commission July 21, 2011
Project Area
Project Commitments Assessment of the Hosgri, Shoreline, and other faults in the vicinity of Diablo Canyon Power Plant (DCPP) California Public Utilities Commission Fault survey using the following methods Offshore three-dimensional (3D) high energy survey Onshore two-dimensional (2D) high energy scope near coast Seafloor geophones nearshore in low water levels
Project Objectives Obtain improved deep (>1 km [>0.6 mi]) imaging of the Hosgri and Shoreline fault zones to better define fault geometry - in the vicinity of the DCPP - at the intersection of the Hosgri and Shoreline fault zones near Point Buchon - at the intersection of the San Simeon and Hosgri fault zones near Point Estero Expand regional seismic database
Offshore Seismic Imaging Survey Cambria to Point San Luis in water up to 1,400 ft. Specialized survey vessel approximately 240 ft in length Vessel-towed individual or multiple strings of tuned air guns with a volume of 3,300 in 3 Vessel-towed hydrophone streamer array of 3 to 5 miles length Additional scout and support vessels
Towed Air Gun Array and Acoustic Streamers
Seismic Survey Process
Survey Track Lines Northern Survey Area 547 miles 22 day survey duration (24/7) Southern Survey Area 765 miles 30 day survey duration (24/7)
Nearshore Seismic Imaging Survey Nearshore areas too shallow for larger survey vessels Seafloor geophones will be placed by smaller vessel Geophone strings to -300 ft water depth (approximately 3 miles offshore) Includes both offshore and onshore sound sources
Geophone Lines in Southern Survey Area
Pacific Gas and Electric Company Onshore Source and Receiver Lines Receiver Lines Only
Source and Receiver Equipment
Survey Schedule and Duration Proposed survey to be conducted September through December 2012 Estimated work period is 3 months with 24 hour operations (6 months if daylight only operations)
Offshore Survey Procedures Marine Wildlife Contingency Plan approved by NOAA Fisheries Pre-activity aerial surveys and equipment noise level testing Established Safety and Exclusion Zones Ramp-up of all air guns Marine mammal monitors onboard all survey vessels Scheduled to coincide with low marine mammal activity (late fall/early winter) Notification to mariners and commercial fishers Avoidance of sensitive resource areas to extent feasible
Anticipated Agency Approvals California State Lands Commission Geophysical Permit (Seismic Survey) California Environmental Quality Act (CEQA) Lead Agency NOAA Fisheries Incidental Harassment Authorization (IHA)/Endangered Species Act (ESA) Consultation Army Corps of Engineers Section 10/404 Certification for marine operations National Environmental Policy Act (NEPA) Lead California Coastal Commission Coastal Development Permit (CDP)/Federal Consistency County of San Luis Obispo CDP for onshore sources/receiver line and Encroachment Permit U.S. Fish and Wildlife Service (FWS) - ESA Consultation California Department of Fish & Game CESA Permits/MPA Authorization California Dept. of Parks and Recreation Encroachment Permit Regional Water Quality Control Board Section 401 Certification U.S. Coast Guard Notice to Mariners