ML020290355
| ML020290355 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 12/21/2001 |
| From: | Womack L F Pacific Gas & Electric Co |
| To: | Document Control Desk, Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation |
| References | |
| +sispmjr200505, -nr, -RFPFR, DIL-01-004 52.27.100.731, Rev 0 | |
| Download: ML020290355 (141) | |
Text
NON-PROPRIETARY CALCULATIONS Book 6 of 8 Attachments to PG&E Letter DIL-01-004 Dated December 21, 2001 Page 1 of 3 69-20132 03/07/01 NUCLEAR POWER GENERATION CF3.ID4 ATTACHMENT
7.2 Index
No. 402 Binder No.'--' TITLE: CALCULATION COVER SHEET Unit(s): 1 & 2 File No.: 52.27 Responsible Group: Civil Calculation No.: 52.27.100.731 No. of Pages 3 pages + Index (4 pages) + 1 Design Calculation YES [x] NO [ Attachment (185 pages) System No. 42C Quality Classification Q (Safety-Related)
Structure, System or Component:
Independent Spent Fuel Storage Facility
Subject:
Analysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site (GEO.DCPP.01.21, Rev. 2) Electronic calculation YES NO [x I Computer Model Computer ID Program Location Date of Last Change Registered Engineer Stamp: Complete A or B "- A. Insert PE Stamp or Seal Below B. Insert stamp directing to the PE stamp or seal REGISTERED ENGINEERS' STAMPS AND EXPIRATION DATES ARE SHOWN ON DWG 063618 Expiration Date: NOTE 1: Update DCI promptly after approval.
NOTE 2: Forward electronic calculation file to CCTG for uploading to EDMS.1 6 69-2013z 03/07/01 (Page 2 of 3 CF3.ID4 ATTACHMENT
7.2 TITLE
CALCULATION COVER SHEET CALC No. 52.27.100.731, RO RECORD OF REVISIONS Rev Status Reason for Revision Prepared LBIE LBIE Check LBIE Checked Supervisor Registered No. By: Screen Method* Approval Engineer Remarks Initials/
Yes/ Yes/ PSRC PSRC Initials/
Initials/
Signature/
LAN ID! No! No! Mtg. Mtg. LAN ID! LAN ID! LAN ID! Date NA NA No. Date Date Date Date 0 F Acceptance of Geosciences Calc. AFT2 [I Yes [ ] Yes [ ]A N/A N/A J/ A No. GEO.DCPP.01.21, Rev. 2. Al -f Calc. supports current edition of ,]IISlo [ ] No [ ] No [ ] B L 23-S-2-10CFR72 DCPP License [x ] NA x ] NA [x]C I72 1 CL/1 /j Application to be reviewed by NRC prior to implementation.
Prepared per CF3.ID17 requirements.
I ]Yes [ ]Yes []A [ ]No [ ]No [ ]B [ ]NA [ ]NA [ ]C [ ]Yes [ ]Yes [ ]A []No []No [lB [ ]NA [ ]NA [ IC *Check Method: A: Detailed Check, B: Alternate Method (note added pages), C: Critical Point Check 2 Pacific Gas and Electric Company Engineering
-Calculation Sheet Project: Diablo Canyon Unit ( )1 ( ) 2 (x) 1&2 SUBJECT Analysis of Bedrock Stratiqiraphy and Geologic Structure at the DCPP ISFSI Site MADE BY A. Tafoya 10 DATE 69-392(10/92)
Engineering CALC. NO. 52.27.100.731 REV. NO. 0 SHEET NO. 3 of 3 12/15/01 CHECKED BY N/A DATE Table of Contents: Item Type 1 Index 2 Attachment A Title Cross-Index (For Information Only) Analysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site Page Numbers 1-4 1 -185 3 Pacific Gas and Electric Company Engineering
-Calculation Sheet Project: Diablo Canyon Unit ( )1 ( )2 (x) 1&2 69-392(10/92)
Engineering CALC. NO. 52.27.100.731 REV. NO. 0 SHEET NO. 1-1 of 4 SUBJECT Analysis of Bedrock Stratipraphy and Geologaic Structure at the DCPP ISESI Site MADE BY A. TafoyaW' DATE 12/15/01 CHECKED BY N/A DATE 1- This table cross references between Geosciences calculation numbers and DCPP (Civil Group's) calculation numbers. This section is For Information Only. Cross-Index (For Information Only) Item Geosciences Title PG&E Calc. Comments No. Calc. No. No. 1 GEO.DCPP.01.01 Development of Young's 52.27.100.711 Modulus and Poisson's Ratios for DCPP ISFSI Based on Field Data 2 GEO.DCPP.01.02 Determination of 52.27.100.712 Probabilistically Reduced Peak Bedrock Accelerations for DCPP ISFSI Transporter Analyses 3 GEO.DCPP.01.03 Development of Allowable 52.27.100.713 Bearing Capacity for DCPP ISFSI Pad and CTF Stability Analyses 4 GEO.DCPP.01.04 Methodology for 52.27.100.714 Determining Sliding Resistance Along Base of DCPP ISFSI Pads 5 GEO.DCPP.01.05 Determination of 52.27.100.715 Pseudostatic Acceleration Coefficient for Use in DCPP ISFSI Cutslope Stability Analyses 6 GEO.DCPP.01.06 Development of Lateral 52.27.100.716 Bearing Capacity for DCPP CTF Stability Analyses 7 GEO.DCPP.01.07 Development of Coefficient 52.27.100.717 of Subgrade Reaction for DCPP ISFSI Pad Stability Checks 8 GEO.DCPP.01.08 Determination of Rock 52.27.100.718 Anchor Design Parameters for DCPP ISFSI Cutslope 9 GEO.DCPP.01.09 Determination of 52.27.100.719 Calculation to be Applicability of Rock Elastic replaced by letter Stress-Strain Values to Calculated Strains Under 1 Pacific Gas and Electric Company Engineering
-Calculation Sheet Project: Diablo Canyon Unit ( )1 ( ) 2 (x) 1&2 SUBJECT Analysis of Bedrock Stratiqraphy and Geologic Structure at the DCPP ISFSI Site MADE BY A. Tafoya 0 DATE 12/15/01 CHECKED BY N/A DATE Cross-Index (For Information Only) Item Geosciences Title PG&E Calc. Comments No. Calc. No. No. DCPP ISFSI Pad 10 GEO.DCPP.01.10 Determination of SSER 34 52.27.100.720 Long Period Spectral Values 11 GEO.DCPP.01.11 Development of ISFSI 52.27.100.721 Spectra 12 GEO.DCPP.01.12 Development of Fling 52.27.100.722 Model for Diablo Canyon ISFSI 13 GEO.DCPP.01.13 Development of Spectrum 52.27.100.723 Compatible Time Histories 14 GEO.DCPP.01.14 Development of Time 52.27.100.724 Histories with Fling 15 GEO.DCPP.01.15 Development of Young's 52.27.100.725 Modulus and Poisson's Ratio Values for DCPP ISFSI Based on Laboratory Data 16 GEO.DCPP.01.16 Development of Strength 52.27.100.726 Envelopes for Non-jointed Rock at DCPP ISFSI Based on Laboratory Data 17 GEO.DCPP.01.17 Determination of Mean and 52.27.100.727 Standard Deviation of Unconfined Compression Strengths for Hard Rock at DCPP ISFSI Based on Laboratory Tests 18 GEO.DCPP.01.18 Determination of Basic 52.27.100.728 Friction Angle Along Rock Discontinuities at DCPP ISFSI Based on Laboratory Tests 19 GEO.DCPP.01.19 Development of Strength 52.27.100.729 Envelopes for Jointed Rock I_ Mass at DCPP ISFSI Using 2 69-392(10/92)
Engineering CALC. NO. 52.27.100.731 REV. NO. 0 SHEET NO. 1-2 of 4 Pacific Gas and Electric Company Engineering
-Calculation Sheet Project: Diablo Canyon Unit ( )1 ( )2 (x) 1&2 CALC. NO.69-392(10/92)
Engineering 52.27.100.731 REV. NO. 0 SHEET NO. 1-3 of 4 SUBJECT Analysis of Bedrock Stratiqraphy and Geologqic Structure at the DCPP ISFSI Site MADE BY A. Tafoya 01 DATE 12/15/01 CHECKED BY N/A DATE Cross-Index (For Information Only) Item Geosciences Title PG&E Calc. Comments No. CaIc. No. No. Hoek-Brown Equations 20 GEO.DCPP.01.20 Development of Strength 52.27.100.730 Envelopes for Shallow Discontinuities at DCPP ISFSI Using Barton Equations 21 GEO.DCPP.01.21 Analysis of Bedrock 52.27.100.731 Stratigraphy and Geologic Structure at the DCPP ISFSI Site 22 GEO.DCPP.01.22 Kinematic Stability Analysis 52.27.100.732 for Cutslopes at DCPP ISFSI Site 23 GEO. DCPP.01.23 Pseudostatic Wedge 52.27.100.733 Analyses of DCPP ISFSI Cutslopes (SWEDGE Analysis) 24 GEO.DCPP.01.24 Stability and Yield 52.27.100.734 Acceleration Analysis of Cross-Section I-I' 25 GEO.DCPP.01.25 Determination of Seismic 52.27.100.735 Coefficient Time Histories for Potential Siding Masses Along Cut Slope Behind ISFSI Pad 26 GEO.DCPP.01.26 Determination of 52.27.100.736 Earthquake-Induced Displacements of Potential Sliding Masses on ISFSI Slope 27 GEO.DCPP.01.27 Cold Machine Shop 52.27.100.737 Retaining Wall Stability 28 GEO.DCPP.01.28 Stability and Yield 52.27.100.738 Acceleration Analysis of Potential Sliding Masses Along DCPP ISFSI Transport Route 3 Pacific Gas and Electric Company Engineering
-Calculation Sheet Project: Diablo Canyon Unit ( )1 ( ) 2 ( x ) 1&2 CALC. NO.69-392(10/92)
Engineering 52.27.100.731 REV. NO. 0 SHEET NO. 1-4 of 4 SUBJECT Analysis of Bedrock Stratiqraphy and Geologic Structure at the DCPP ISFSI Site MADE BY A. Tafoya 0 DATE 12/15/01 CHECKED BY N/A DATE Cross-Index (For Information Only) Item Geosciences Title PG&E Calc. Comments No. Calc. No. No. 29 GEO.DCPP.01.29 Determination of Seismic 52.27.100.739 Coefficient Time Histories for Potential Sliding Masses on DCPP ISFSI Transport Route 30 GEO.DCPP.01.30 Determination of Potential 52.27.100.740 Earthquake-Induced Displacements of Potential Sliding Masses Along DCPP ISFSI Transport Route 31 GEO.DCPP.01.31 Development of Strength 52.27.100.741 Envelopes for Clay Beds at DCPP ISFSI 32 GEO.DCPP.01.32 Verification of Computer 52.27.100.742 Program SPCTLR.EXE 33 GEO.DCPP.01.33 Verification of Program 52.27.100.743 UTEXAS3 34 GEO.DCPP.01.34 Verification of Computer 52.27.100.744 Code -QUAD4M 35 GEO.DCPP.01.35 Verification of Computer 52.27.100.745 Program DEFORMP 36 GEO.DCPP.01.36 Reserved 52.27.100.746 37 GEO.DCPP.01.37 Development of Freefield 52.27.100.747 Ground Motion Storage Cask Spectra and Time Histories for the Used Fuel Storage Project 4 FROM Cluff -San Francisc Calculation 52.27.100.731, Rev. 0, Attachment A, Page _1otf I. 200, 0 PHONE NO. 415 564 SHUL ELU1IWNCLE5 DLP NO.089 PG&E Geosclences Department Departmental Calculation Procedure Title- Calculation Cover Sheet Page: I of I PACIFIC GAS AND ELECTRIC COMPANY GEOSCIENCES DEPARTMENT CALCULATION DOCUMENT Colo Number, Revision: GEO.DCPP.
01.21 2 December 14, 2001 No. of Calo Pages: 181 Verification Method: No. of Verification Pages: 2 "-ht TITLE IAnalysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site PREPARED BY VERIFIED BY APPROVED BY lam R.NLeIs Pritied Name Scott C, Lindvall Printed Name Uoyd S. Cluff Printed Name DATE 12114/01 Wlliam Lettla & Assoolatea, Inc. Organization DATE WIlliam Lattls & Ansoclates, Inc. Organl.ation DATE PG&E Geosclences Dept. Organization
"-I .... od lop~u /GEO.DCPP.01.2 1, RV, 2 4: UWII'll 6697 P.1X5 ,V i01t-/xýpcýýPag~e I ofl191 thic-nbe-14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page -2 of 185 PG&E Geosciences Department Departmental Calculation Procedure Title: Calculation Cover Sheet Page: 1 of 1 PACIFIC GAS AND ELECTRIC COMPANY GEOSCIENCES DEPARTMENT CALCULATION DOCUMENT Calc Number: Revision:
Date: GEO.DCPP.
01.21 2 December 14, 2001 No. of Calc Pages: 181 Verification Method: No. of Verification Pages: 2 TITLE Analysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site PREPARED BY A'DATE 12/14/01 VERIFIED BY APPROVED BY William R. Lettis " Printed Name Scott C. Lindvall Printed Name Lloyd S. Cluff Printed Name DATE DATE William Lettis & Associates, Inc. Organization William Lettis & Associates, Inc. Organization PG&E Geosciences Dept. Organization GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page I of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 3 of 185 PG&E Geosciences Department Departmental Calculation Procedure Page: 1 of 1 Title: Record of Revision Calc Number: GEO.DCPP.01.21 Analysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site Rev 2 I t Remove letter designations from Record of Revisions (pg. 2); added references to the transmittals of maps and air photos from PG&E Geosciences to WLA; edited the section on Topographic maps (formerly 2.2 and now 2.1); added information on x-ray diffraction to the stratigraphic descriptions (5.2.1 to 5.2.3); revised the geologic maps (Figs. 21-1, 21-3, and 21-4) and cross sections (Figs. 21-14 to 21-25); added cross section L-L'; added sections on rockslide mass models (5.6.3) and estimate of potential slide mass displacement (5.6.4); changed section 5.6.3 Rock Block Dimensions to section 5.6.5; general minor edits to text and figures.11/6/01 Revision Date Reason for Revision Rev. No..1- r 10/15/01 Initial Issue 0 Rev 1 I_ _ L 12/12/01 Revised Introduction (Section 1); added description of geology along the transport route (5.5); added discussion of origin and non capability of minor faults in the ISFSI study area (5.3.2.1);
discussion of pre-existing landslides in Diablo Canyon near ISFSI site (5.7.1); general minor edits to text and figures in response to QA and ITR review________________________________
4 I-_______________ -I-__________________________I December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 2 of 181 I I Calculation 52.27.100.731, Rev. 0, Attachment A, Page -of 185 DCPP ISFSI CALCULATION PACKAGE GEO.DCPP.01.21 Analysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 3 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page r of 185 DCPP ISFSI Calculation package GEO.DCPP.01.21 Analysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site Table of Contents Paze
1.0 INTRODUCTION
............................................................................................
8 1.1 Location and Site Description
...............................................................
9 1.2 Purpose ...................................................................................................
9 2.0 INPUTS ................................................................................................................
12 2.1 ISFSI Project M aps and Air Photos ....................................................
12 2.2 Compilation of Topographic Base M aps ............................................
15 2.3 Geologic Input .....................................................................................
17 3.0 ASSUM PTION S ..............................................................................................
19 4.0 M ETHODS ....................................................................................................
22 4.1 Bedding ..............................................................................................
22 4.2 Clay Beds ............................................................................................
24 4.3 Cross Sections .....................................................................................
25 5.0 ANALYSIS (BODY OF CALCULATION)
..................................................
30 5.1 Bedrock Evolution
..............................................................................
30 5.2 Stratigraphic Analysis ..........................................................................
38 5.2.1 General Stratigraphy
..............................................................
38 5.2.2 ISFSI Study Stratigraphy
.......................................................
38 5.2.2.1 Dolomite (Unit Tofb-1) ..............................................
40 5.2.2.2 Sandstone (Unit Tofb-2) ............................................
41 5.2.2.3 Friable Bedrock .......................................................
42 5.2.2.4 Clay Beds ................................................................
44 5.3 Structural Analysis ..............................................................................
47 5.3.1 Folds .......................................................................................
48 December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 4 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 4 of 185 Table of Contents (continued)
5.3.2 Faults
........................................................................................
50 5.3.2.1 Fault Origin and Capability
.......................................
52 5.3.3 Bedrock Discontinuities
..........................................................
54 5.4 Stratigraphy and Structure of the ISFSI Pads Foundation
..................
57 5.5 Stratigraphy and Structure of the Transport Route ..............................
58 5.6 Comparison of Power Block and ISFSI Site ........................................
62 5.7 Parameters Recommended for Stability Analysis ...............................
64 5.7.1 Pre-existing Landslides in Diablo Canyon near the ISFSI Site ... 64 5.7.2 Clay Bed Strength ...................................................................
66 5.7.3 Geometry and Structure of Slide Mass Models .......................
67 5.7.4 Conceptual Rockslide Mass Models ........................................
68 5.7.5 Estimate of Potential Slide Mass Displacement
.....................
70 5.7.6 Rock Block Dimensions
.........................................................
72 R E SU L T S ............................................................................................................
73 SOFTWARE ...................................................................................................
73 CONCLUSIONS
............................................................................................
74 REFERENCES
................................................................................................
75 List of Tables Table 21-1 Interpretation of bedding in boreholes, ISFSI study area. Table 21-2 Evaluation of clay 'seams' on low-angle fractures and bedding, ISFSI study area borings.
Table 21-3 Thickness measurements of clay beds in borings and trenches.
Table 21-4 Friable rock zones in ISFSI study area borings.
Table 21-5 Discontinuity data for minor faults. Table 21-6 Selected fractures (joints, faults and shears) observed in borings and trenches.
Table 21-7 Comparison of seismic wave velocities in the ISFSI study area and at the DCPP power block.GEO.DCPP.0 1.2 1, Rev. 2 6.0 7.0 8.0 9.0 December 14, 2001 Page 5 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page _j_ of 185 List of Table of Contents (continued)
List of Figures Figure 21-1. Figure 21-2. Figure 21-3. Figure 21-4. Figure 2 1-5. Figure 21-6. Figure 21-7. Figure 21-8. Figure 21-9. Figure 21-10. Figure 21-11. Figure 21-12. Figure 21-13. Figure 2 1-14. Figure 21-15. Figure 2 1-16. Figure 21-17. Figure 21-18. Figure 21-19. Figure 21-20. Figure 21-21. Figure 21-22. Figure 21-23. Figure 21-24. Figure 21-25. Figure 21-26.Geologic map of bedrock and landslides in the plant site area. Aerial view of the ISFSI study area. Geologic map of the ISFSI study area and transport route vicinity.
Geologic map of ISFSI and CTF sites. Generalized stratigraphic column at the ISFSI and power block sites. Index map of topographic surveys.
Diagrammatic cross section illustrating the depositional and structural history at the ISFSI. Chronology of stratigraphy and geologic processes at the ISFSI study area. Summary logs of borings on slope above ISFSI site. Summary logs of borings near southwest end of ISFSI site. Summary logs of borings at ISFSI site. Summary logs of borings near east end of ISFSI site. Explanation for cross sections.
Cross section A-A'. Cross section B-B"'. Cross section C-C'. Cross section D-D'. Cross section E-E' Cross section F-F' through Patton Cove landslide.
Cross section G-G'. Cross section H-H'. Cross section I-I'. Cross section J-J'. Cross section K-K'. Cross section L-L' Measuring bedding attitude, ISFSI study area.GEO.DCPP.01.21, Rev. 2 Page 6 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 9 of 185 Table of Contents (continued)
List of Figures (continued)
Figure 21-27. Figure 21-28. Figure 21-29. Figure 21-30. Figure 21-31. Figure 21-32. Figure 21-33. Figure 21-34. Figure 21-35. Figure 21-36. Figure 21-37. Figure 21-38. Figure 21-39. Figure 21-40. Figure 21-41. Figure 21-42. Figure 21-43. Figure 21-44. Figure 21-45. Figure 21-46. Figure 21-47.Examining core from ISFSI study area. Core boxes from ISFSI study area laid out in stratigraphic order. Clay bed in Trench T-14B. Clay bed at 55 feet in Boring OOBA-l. Clay bed at 130 feet in Boring 01-I. Minor fault in Trench T- 1. Bedded dolomite on Reservoir Road. Minor fault in Trench T-20A. Sandstone outcrop in ISFSI study area. Clay beds and dolomite in Trench T- 11 C. Regional structure map. Comparison of orientations of minor faults and folds in the ISFSI study area with other structures.
Minor faults in Diablo Creek Road. 1968 aerial photograph of ISFSI study area. Azimuth plot of faults and joints in borings and trenches.
Geology of ISFSI and CTF SITES at proposed final grades. Summary log of 1977 Power Block Boring DDH-D. ISFSI site suspension logs and interpreted average seismic velocities.
Comparison of seismic shear-wave velocities at the Power Block and ISFSI sites. Slide mass model 1. Slide mass model 2.Figure 21-48. Slide mass model 3.GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 7 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 2 L of 185 Calculation Package GEO.DCPP.01.21 Title: Analysis of Bedrock Stratigraphy and Geologic Structure at the DCPP ISFSI Site Calc Number: GEO.DCPP.01.21 Revision:
Rev. 2 Author: William R. Lettis Date: December 14, 2001 Verifier:
Scott C. Lindvall
1.0 INTRODUCTION
The Diablo Canyon Power Plant (DCPP) Independent Spent Fuel Storage Facility (ISFSI) will be located on the plant site property in an area underlain by bedrock of the Tertiary Obispo Formation (Figure 21-1). The ISFSI will include the ISFSI pads, a Cask Transfer Facility (CTF), and a transport route leading from the power block to the CTF and onto the ISFSI pads. The ISFSI pads will be constructed on a bench cut into the Obispo Formation.
For the purpose of discussion in this calculation package, the ISFSI pads, CTF, and cutslope and existing hillslope above the ISFSI pads are referred to as the ISFSI study area. The transport route includes the proposed route and the adjoining slopes above and below the route. This calculation package describes the geology of the ISFSI study area and along the transport route. The stratigraphic and structural analysis was performed by William Lettis, Jeff Bachhuber, and Charles Brankman of WLA under the project direction and participation of William Page of PG&E Geosciences.
The preparation of this calculation package was performed under the 2000 WLA Work Plan (Rev. 2) (William Lettis & Associates, Inc., Work Plan, 2000) using data collected under that Work Plan and a second WLA Work Plan (Rev. 1) (William Lettis & Associates, Inc., Work Plan, 2001)GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 8 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page ji of 185 1.1 Location and Site Description The ISFSI study area is located on a prominent ridge directly south of the Raw Water Reservoir and east of the Diablo Canyon power plant (Figures 21-1 and 21-2). The ridge area was used formerly as a borrow source to derive fill material for construction of the 230 kV and 500 kV switchyards.
The borrow excavation, performed in 1971, removed up to 100 feet of material from the ISFSI site area and extended deep into bedrock. As a result, the ISFSI and CTF facilities will be founded on bedrock, and the foundation stability and seismic response will be controlled by the bedrock properties.
The former borrow activity at the site stripped surficial soil and weathered rock from the hillside above the ISFSI site, leaving a bedrock slope covered with a veneer of rock rubble. The proposed cutslopes south of the ISFSI pads will be cut entirely in bedrock. Therefore, understanding the structural geometry and rock mass characteristics of bedrock are important for evaluating slope stability of both the existing slope and the proposed cutslopes.
The transport route follows existing paved roads from the power block to the CTF and onto the ISFSI pads, except for a new portion of the route from Shore Cliff Road to Reservoir Road that will be constructed to avoid a landslide at Patton Cove along the coast (Figure 21-3). The route is located on a nearly flat, graded surface along Plant View and Shore Cliff roads, and progressively climbs elevation along the new bypass road and along Reservoir Road. The bypass road will be constructed, and the lower part of Reservoir Road is constructed, on engineered fill over thick colluvium.
The upper part of Reservoir Road is constructed on a cut-and-fill bench into bedrock of the Obispo Formation.
1.2 Purpose
This calculation package presents detailed analyses to characterize the stratigraphy and structure of bedrock in the ISFSI study area and along the transport route. Understanding the bedrock stratigraphy and structure is important for four purposes:
(1) to evaluate December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 9 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page _1\ of 185 foundation properties for the ISFSI pads, the CTF facility, and the transport route; (2) to evaluate stability of the proposed cut slopes and existing hillslope above the ISFSI pads and transport route; (3) to identify and characterize bedrock faults in the study area; and (4) to compare bedrock conditions at the ISFSI site to bedrock conditions beneath the power block for ground motion characterization.
Information on the stratigraphy, structure and rock mass properties of the bedrock was used to analyze foundation properties, hillslope and cutslope stability, and ground motion site response in the ISFSI study area and along the transport route. These analyses are contained in the following calculation packages:
Calculation packages that characterize the ISFSI pads foundation properties:
GEO.DCPP.01.01 GEO.DCPP.01.03 GEO.DCPP.01.04 GEO.DCPP.01.06 GEO.DCPP.01.07 GEO.DCPP.0 1.15 Development of Young's Modulus and Poisson's ratios for DCPP ISFSI based on field data Development of allowable bearing capacity for DCPP ISFSI pad and CTF stability analyses Methodology for determining sliding resistance along base of DCPP ISFSI pads Development of lateral bearing capacity for DCPP CTF stability analyses Development of coefficient of subgrade reaction for DCPP ISFSI pad stability checks Development of Young's Modulus and Poisson's ratio values for DCPP ISFSI based on laboratory data GEO.DCPP.01.21, Rev. 2 Page 10 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page A1 of 185 Calculation packages that evaluate slope stability of the existing hillslope above the ISFSI site, the proposed ISFSI cutslopes, and the roadcuts above the transport route: GEO.DCPP.01.08 GEO.DCPP.01.19 GEO.DCPP.01.20 Determination of rock anchor design parameters for DCPP ISFSI cutslope Development of strength envelopes for jointed rock mass at DCPP ISFSI using Hoek-Brown equations Development of strength envelops for shallow discontinuities at DCPP ISFSI using Barton equations GEO.DCPP.01.22 Kinematic stability analysis for cutslopes at DCPP ISFSI site GEO.DCPP.01.23 Pseudostatic wedge analysis of DCPP ISFSI cutslope (SWEDGE analysis)
GEO.DCPP.01.24 Stability and yield acceleration analysis of cross section I-I' GEO.DCPP.0 1.25 Determination of seismic coefficient time histories for potential sliding masses along cutslope behind ISFSI pad GEO.DCPP.01.26 Determination of earthquake-induced displacements of potential sliding masses on DCPP ISFSI slope GEO.DCPP.01.28 Stability and yield acceleration analysis of potential sliding masses along DCPP ISFSI transport route GEO.DCPP.01.29 Determination of seismic coefficient time histories for potential sliding masses on DCPP ISFSI transport route December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 11 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1__ of 185 GEO.DCPP.01.30 Determination of earthquake-induced displacements of potential sliding masses along DCPP ISFSI transport route Calculation packages that provide the rock conditions for evaluating ground motion site response:
GEO.DCPP.01.02 Determination of probabilistically reduced peak bedrock accelerations for DCPP ISFSI transporter analyses GEO.DCPP.01.11 Development of ISFSI spectra 2.0 INPUTS 2.1 ISFSI Project Maps and Air Photos Maps showing the topography of the plant site area and of the ISFSI project facility locations were received from PG&E Geosciences Department under letter of transmittal dated October 26, 2001 (PG&E Geosciences, 2001b). These maps were used to prepare the base maps for the geologic maps presented in this Calculation Package.DRAWING 471124 PGE-009-SK-001 UFSP-SK-004 USFP-SK-005 354970 438042 REVISION 1 [0 A A I 18 TITLE Plot Plan Site Plot Plan, ISFSI Cask Storage Pad, Cask Transfer Facility Cask Transfer Facility Structure (Schematic)
Four Topographic Profile Surveys (CYN-14r.dgn)
Site Plan Liquid Storage Warehouse Finished Grading Plan, Plant Area December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 12 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page -i of 185 DRAWING 445669 445670 445675 445708 445719 445720 445724 445725 445726 445727 445731 445732 472116 472117 472118 472119 472679 512292 515971 515973 516969 516992 516994 REVISION 2 7 12 1 0 0 0 0 0 0 0 0 4 3 4 3 7 11 4 3 8 8 5 TITLE As Built Location of Overhead Power Lines and Property Access Road As Built Location of Compressor Building and Surrounding Buried & Overhead Utilities As Built Location of Buried Conduits, Overhead Power Line, Meteorological Facilities
& Intake Structure As Built Location of Intake Structure Area & Breakwater Road Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Access Road to 150 ft. Meteorological Tower Finish Grading & Drainage Plan N.P.O. Permanent Warehouse Drainage Sections & Details N.P.O. Permanent Warehouse Vehicular Access Plan & Misc. Details N.P.O. Permanent Warehouse Foundation Plan and Details NPO Permanent Warehouse Fencing Plan and Detail for the Southern Portion of the Power Plant Yard Site Master Plan Master Plan Area A Finished Grading Plan Yard Area and Administration Building Concrete Outline Foundation Plan Administration Building Ground Floor Plan Cold Machine Shop Finished Grading Plan Cold Machine Shop Foundation, Plan and Details Cold Machine Shop December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 13 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page QS of 185 DRAWING 517998 Diablo-pns-x l x CYN-rl 4.dwg 71498.asc 61600.asc 122000.asc 42301.asc 9601 .asc 59451 478104 57733 438002 438003 438023 438034 438200 439514 443060 443061 455934 455937 500973 REVISION 4 7/14/98 6/16/00 12/20/00 4/23/01 9/6/01 & 9/7/01 7 1 "11 8 2 2 7 7 9 9 2 2 3 13 TITLE Plan, Sections & Details Stormwater/Transformer Deluge Retention Drainage System The Points Lists submitted by Pacific Engineering for four topographic profile lines D-D', E-E', F-F' and I-I' A sketch prepared by Pacific Engineering showing in plan the routes of the four field survey lines and can serve as a guide to the relative locations of the tabulated data "Topo" of hillside Trenches Added trenches Bores Cross sections Plot Plan (Superseded)
Surveys of sea floor terrain near Diablo Canyon and of breakwater configuration after wavestorm of January 28, 1981 Equipment location Section FF Auxiliary, Fuel Handling and Turbine Buildings Excavation Plan Plant Site Excavation sections Plant Site May, 1968, Topography Plant Site Area Foundations for water tanks Excavation for containment, turbine-generator
& auxiliary buildings Concrete outline section J-J Auxiliary Building Areas H & K Excavation of Turbine Building Excavation of Auxiliary Building Excavation, Grading Plan & Sections Solid Radwaste Storage Building Finish Grading Plan & Sections Solid Radwaste Storage Building Equipment Location Section "C-C" Turbine, Containment
& Fuel Handling Buildings December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 14 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page L, of 185 DRAWING 517120 517746 517780 REVISION 7 1 10 TITLE Fencing and Grading Radwaste Storage and Laundry Facility Area Site Preparation Plan & Sections NPO Permanent Warehouse Finish Grading Plan and Sections Radwaste Storage Building In addition, stereo aerial photographs of the ISFSI study area and transport route were acquired and interpreted for the study. These photos include: Date 5/22/68 Company Towill Corporation 7/4/86 PG&E 1/11/87 PG&E 7/13/00 Golden Aerial Surveys Frames Flight 2777 Frames 2808-1 to 2808-3 Flight 2773 Frames 2805-3 and 2805-4 Flight PG&E 737 Frames 2-159, 2-160 and 2-114 to 2-116 Flight PG&E 753 Frames 5-10 to 5-12 and 6-4 to 6-9 Flight GS4295 Frames 1-1 to 1-6 and 2-1 to 2-2 Scale 1:24,000 black & white 1:24,000 color 1:24,000 black & white 1:20,000 color 2.2 Compilation of Topographic Base Maps Four different topographic base maps were compiled to make a complete topographic map of the ISFSI study area and transport route. This topographic map was used as the base map for preparation of geologic maps and cross sections.
As shown on Figure 21-6 and discussed below, these maps cover different parts of the plant site at different scales and topographic contour intervals:
GEO.DCPP.01.21, Rev. 2 Page 15 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 11 of 185 (1) Towill Corporation's topographic map of the power plant property based on 1966 aerial photography and prepared at a scale of 1:2,400. These maps were made prior to power plant construction and site grading, and have gone through numerous revisions that primarily consist of addition of site facilities and areas of major grading. Elevation contours are 5 to 10 feet. These maps are used to depict topography outside of graded areas and facilities.
The pre-construction topography from these maps was also plotted on several cross sections to illustrate the geomorphology prior to construction.
(2) PG&E's 1986 facility layout Plot Plan map, Sheet No. 471124, prepared at a scale of 1:2,400. This plan shows as-built footprints of site facilities and graded areas (such as parking lots and the switchyard fill pads), overprinted on a modified topographic base with 100-foot elevation contours taken from the Towill topographic map. (3) PG&E's topographic/civil maps prepared at a scale of 1:240 (referred to as the "20-scale civil drawings")
and modified at various times since the early 1970s. The 20-scale topographic/civil maps include as-built topography and facility layouts. These maps have gone through numerous revisions to incorporate new facilities or changes in graded conditions, but do not include all newer facilities and changes. Contour intervals are typically 5 feet. The topography from the 20-scale drawings is used to show current as built elevation contours in the areas of the power plant. (4) 2000-2001 ISFSI Site topographic map prepared at a scale of 1:600 (referred to as "ISFSI site map"). The ISFSI site map covers the ISFSI and CTF sites, and is based on both photogramatic and land surveys. Several phases of field surveys were performed to locate exploratory borings, trenches, geologic reference points, and cross section profiles.
Topographic contours December 14,2001 GEO.DCPP.01.21, Rev. 2 Page 16 oflS11 Calculation 52.27.100.731, Rev. 0, Attachment A, Page it of 185 are resolved to 5-foot vertical intervals.
This map is used as the base for Figure 21-4 and for cross sections in this area. The geologic maps shown on Figures 21-1, 21-3 and 21-4 cover different parts of the power plant site area and ISFSI study area and, thus, required the use of one or more of the different topographic maps. The different base maps were merged to create a uniform topographic base registered to the California State Coordinate System that is a common grid for cross-referencing.
The contours were smoothed and adjusted at the map boundaries to eliminate mismatching at map edges. Some contour lines were removed to provide consistent map-to-map contour spacing. After the base topography was merged and edited, selected major plant facilities were added for reference.
In the ISFSI site area, field surveys were also made to accurately locate the ISFSI borings and trenches.
In order to provide accurate topography for the cross section profiles that extended into areas of the older Towill topographic map, the profiles were surveyed in the field as shown on Figure 21-6. These survey profiles, as well as the surveyed points in the ISFSI site area, were used to cross check between the various map sets and provide additional control for geologic data. 2.3 Geologic Inputs Bedrock in the ISFSI study area has undergone a complex history of deposition, alteration and deformation.
This complex history makes it difficult to recognize and correlate distinct lithologies and to identify bedding within the bedrock. Therefore, considerable effort was made to resolve this history and to understand the current stratigraphic and structural condition of the rock. This effort included: " detailed surface mapping (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report A); " continuous rock coring (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report B) supplemented by downhole velocity measurements (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report C) and caliper December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 17 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page ii of 185 and optical televiewer data (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report E); seismic surface refraction surveys (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report C);
- trenching (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report D) and measuring of rock discontinuities (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report F), in situ strength properties (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report H), and structure (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report A); "* laboratory analysis of rock mass properties (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report I) and of clay bed properties (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report G); and "* petrographic and x-ray analyses of hand and core samples (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Reports J and K, respectively).
The details of each study, including methodology, personnel involved, and sequence and results of investigation are given in each respective William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report prepared by William Lettis & Associates, Inc. (2001). Descriptions of the regional and site geology are provided in William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report A, which presents geologic maps and field data with minimal interpretation.
This calculation package integrates the geologic map information included in William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report A with the subsurface and laboratory test data in William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Reports B through K to evaluate site-specific stratigraphy for the ISFSI study area. Interpretive geologic maps are shown on Figures 21-1, 21-3, and 21-4, and a site-specific stratigraphic column is shown on Figure 21-5. The stratigraphy was then used to define the structure and geometry of bedding and the distribution of bedrock lithology beneath the ISFSI and CTF sites, within the slope above the ISFSI site and along the transport route, and to help December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 18 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1.0 of 185 identify and characterize the minor faults in the area. Topographic base maps used for Figures 21-1, 21-3 and 21-4 are shown on Figure 21-6. This calculation package documents the iterative and interpretive procedures used to prepare: (1) a detailed stratigraphic column for bedrock in the study area (Figure 21-5); (2) a geologic model describing the evolution of bedrock in the study area (Figures 21-7 and 21-8); and (3) interpretive geologic maps (Figures 21-1, 21-3 and 21-4), summary boring logs (Figures 21-9 through 21-12), and cross sections (Figures 21-13 through 21 24) showing bedrock structure and distribution of lithologic units at the ISFSI and CTF sites and along the transport route. These data provide rock properties that were used to characterize slope stability, foundation response, and seismic ground motions. Particular emphasis was placed on correlating sedimentary facies, marker beds, and clay beds within the bedrock, and characterizing bedrock structure for use in evaluating the stability of cutslopes and hillslopes in the ISFSI study area and along the transport route. 3.0 ASSUMPTIONS Several assumptions are used in the stratigraphic and structural analysis.
These assumptions and supporting rationale are listed below. Evidence supporting these assumptions is provided in the Analysis section below. These assumptions are considered reasonable and are used to characterize the range of possible conditions of bedrock in the study area. (1) Lateral Continuity.
Bedrock in the ISFSI study area was deposited in a moderate to deep marine environment (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report L). Under such conditions, it is reasonable to assume that individual beds and groups of beds were deposited with lateral continuity of equal to or greater extent than the ISFSI site dimensions (on the order of hundreds of feet). Thus, any interruptions to bedding across the site will be due to post-depositional erosion, chemical alteration, diagenesis (including GEO.DCPP.01.21, Rev. 2 Page 19 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page MA of 185 compaction), deformation (tectonic or non-tectonic), hydrocarbon or hydrothermal fluid migration, and/or igneous intrusion.
Under this assumption, clay beds are conservatively assumed to be laterally continuous for distances of hundreds of feet unless demonstrated otherwise.
This assumption is realistically conservative because field observations of facies changes, areas of rock-to-rock contact, localized cemented bedding planes (rock bridges), and faults commonly disrupt the continuity of bedding and clay beds. (2) Facies Variation.
Bedrock in the ISFSI study area includes both marine turbidite deposits and marine pelagic and biogenic deposits.
These deposits are interfingered and undergo lateral facies transition from one to the other. This facies transition is an irregular, but mappable lithologic contact in the ISFSI study area. Given this depositional contact and general knowledge of depositional environments, the facies transition is assumed to be time-transgressive.
Locally distinct beds of one facies interfinger with the other facies. In these instances, the facies contact is assumed to closely approximate an individual bed or group of beds that can be used to establish the general dip and lateral continuity of bedding within the bedrock. This is a reasonable assumption where stratigraphic sequences are constrained by closely spaced borings and surface exposures.
The overall geometry of the facies transition, however, given its interfingering pattern, will appear to cross cut bedding.
(3) Dolomitization.
Bedrock in the ISFSI study area has been partially, and in places, entirely recrystallized to dolomite.
This process of dolomitization has affected all rock types and beds to varying degrees and, in places, the degree of dolomitization may vary laterally along the same bed(s). Thus, the degree of dolomitization cannot be used as a distinct lithologic unit that defines bedding or distinct marker horizons in the site area. However, the finer-grained dolomite beds of Unit Tofb-. generally exhibit a greater degree of dolomitization than the coarser-grained sandstone beds of Unit Tofb-2.GEO.DCPP.01.2 1, Rev. 2 December 14, 2001 Page 20 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page l-Z of 185 (4) Alteration.
Bedrock in the ISFSI study area has undergone several periods of alteration, including addition of petroliferous fluids, near-surface mechanical and chemical weathering and probable hydrothermal alteration.
Based on detailed mapping, the petroliferous alteration is assumed to be relatively random throughout the bedrock and cannot be used to discriminate either original bedrock lithology or bedding. In contrast, the surface weathering and/or hydrothermal alteration appears to have differentially effected distinct lithologies and beds over short distances.
These zones of alteration are assumed to correlate laterally over short distances and, therefore, can be used to help evaluate the stratigraphy and structure of bedrock in the ISFSI study area. (5) Diabase Intrusion.
Rocks of a diabase intrusive complex are common in the Diablo Canyon plant site area and locally were present in the ISFSI site prior to excavation of the borrow site in 1971. Because of the proximity of known diabase intrusions, bedrock at the site may have been structurally deformed by the intrusive complex and/or hydrothermally altered from fluids emanating from the intrusion.
This is a reasonable assumption considering the known occurrence and former proximity of the diabase.
(6) Bedding Attitudes.
Bedding attitudes obtained at the surface and in boreholes are assumed to reflect the geometry of adjacent bedrock, and that this bedding attitude can be projected along dip and strike for distances up to 100 feet. This is a reasonable assumption that is supported by the greater than 100 bedrock attitudes measured in the ISFSI study area. Changes in bedding attitudes between different locations are interpolated using geologic judgement and interpretation of fold and fault geometry.
(7) Faulting.
Several minor faults occur in the ISFSI study area. The faults are assumed to have lateral and vertical continuity at least equal to the dimensions of the site (on the order of hundreds of feet). In addition, the faults are assumed to project along trend to small bedrock faults observed on the north wall of Diablo December 14, 2001 GEO.DCPP.01.2 1, Rev. 2 Page 21 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page Z-3 of 185 Canyon that have similar geometry and orientations.
These assumptions are reasonable given the inferred amounts of displacement on the faults (several hundred feet or more). In addition, slickensides are preserved on several exposed fault planes. The orientation of the slickensides are assumed to reflect the sense of last displacement along the fault, a commonly accepted interpretation of fault displacement.
Where the fault plane attitude is not well constrained, we assume that the fault is vertical.
This assumption is reasonable since the sense of fault displacement is primarily strike slip and the majority of measured fault dips are greater than 70 degrees. Faults with a well-constrained geometry are shown with a solid line on the cross sections; faults with a poorly constrained geometry are shown with a dashed line. 4.0 METHODS Stratigraphic and structural analyses of bedrock in the ISFSI study area and along the transport route were performed using fundamental principals of geology (e.g., uniformitarianism, stratigraphic superposition and lateral continuity, cross-cutting relative age relationships, etc.). Geologic data were collected in the field through surface geologic mapping, seismic surveys, trenching and borings (see Inputs section above). The data were compiled and analyzed using guidelines provided in "Geology in the Field" (Compton, 1985). Geologic field data were supplemented with laboratory petrographic and X-ray diffraction analyses (see Inputs Section above). 4.1 Bedding Bedding attitudes were measured to evaluate stratigraphic continuity and geometry of bedrock in the study area and at the site. Particular care was used in measuring bedding in the ISFSI study area because of the importance to the analysis of slope stability.
Attitudes were obtained on surface outcrops using a Brunton Compass (Figure 21-26) and in borings using optical televiewer data supplemented by visual examination of the rock GEO.DCPP.01.21, Rev. 2 Page 22 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page Zt of 185 core (Figure 21-27). All of the bedding attitudes obtained from surface outcrops in the ISFSI study area and most of the attitudes from the borings were cross-checked by at least two geologists as described in William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Reports B, E, and L. Surface measurements of bedding attitudes were obtained from available exposures that exhibited moderate to well-defined bedding.
These attitudes were used to help determine bedrock structure (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report L, Table L-1). All bedding attitudes from surface exposures were plotted on the geologic maps and those near the cross section lines were used in the construction of these cross sections across the ISFSI study area and along the transport route. Bedding attitudes also were measured in borings by examination of televiewer data, rock core, and boring logs. Distinct beds and/or zones of "stratified" or laminated bedrock were initially noted on the geologic logs by the field geologist upon first examination of the recovered core (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report B). The dip of bedding was measured directly on the core with a protractor.
Oriented coring techniques were not used; therefore, the strike and dip azimuth of bedding could not be determined in the field. Most of the dip measurements of bedding were checked by visual examination of the rock core by at least two other geologists (Figures 21-26 and 21-27). Borehole televiewer data were processed and interpreted by NORCAL (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report E). NORCAL identified bedding planes and defined the orientation and dip of selected bedding planes. The NORCAL data were independently checked by at least two geologists by comparing the televiewer data with the rock core. Additional bedding planes, or alternate measurements of NORCAL bedding measurements were made by the geologists using geometric and trigonometric solutions.
Most of the bedding attitudes determined from the televiewer data were compared visually with the rock core to verify the existence of bedding as noted on the televiewer logs and the magnitude of dip as calculated from the televiewer logs. Cross-checking between the televiewer data, rock core, and boring logs provided a consistent, verifiable and documented set of bedding attitudes.
Bedding attitudes in the borings are tabulated in Table 21-1. Only those beds December 14, 2001 GEO.DCPP.0 1.2 1, Rev. 2 Page 23 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page .-j of 185 that were verified by visual examination of the core were used in the construction of cross sections across the ISFSI study area. 4.2 Clay Beds The identification and characterization of clay beds in the ISFSI study area is important for two reasons: (1) The clay beds form local marker horizons that help define the structure and geometry of bedding in the study area; and (2) the clay beds could form a basal shear surface for potential shallow and deep slope failures that might affect the ISFSI. Thus, a significant effort was focused on identifying clay beds and evaluating their orientation and lateral continuity.
Distinct clay beds were observed in trench exposures, boreholes, and roadcut exposures (Figures 21-28, 21-29, 21-30). Clay beds were identified and logged in Trenches T-11, T-12, T-14, T-15 and T-1 8 (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report D). In each trench the thickness and attitude of the clay were recorded.
Locations of clay beds observed in trenches and surface exposures are shown on Figure 21-4. Clay beds also were identified in many of the borings (Table 21-2). The clay beds are more common and generally thicker in the dolomite bedrock (Unit Tofb-l) and less common and thinner in the sandstone bedrock (Unit Tofb-2) (Table 21-3). The identification of a clay bed (as opposed to a clay-filled fracture or joint) in the borings required careful analysis.
The differentiation of clay beds from joint and fracture clay infills was initially noted by the geologist in the field during core logging (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSL Data Report B). This information was reviewed and verified by at least two geologists through visual inspection of the rock core. Because confirmed bedding attitudes defined by clear stratigraphic laminations typically dip in the range of about 5 to 20 degrees, only clay occurrences with a dip of less than 30 degrees and judged to be a clay bed were identified as possible clay beds for incorporation in cross sections and highlighted by bold font in Table 21-2. Clay seams December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 24 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 2.f, of 185 dipping steeper than 30 degrees are interpreted to be clay coatings and infillings along faults and joints rather than stratigraphic clay beds and were not tabulated in Table 21-2. Borehole televiewer data also provide documentation of the presence of in situ clay beds. Clay beds were identified in the televiewer images as zones of borehole erosion, "softer" and blocky to massive layers, and non-jointed zones between more brittle jointed rock. This information is particularly useful in portions of the borings where the recovery of rock core was less than 100 percent. NORCAL provided the initial interpretation of the optical televiewer data and identified possible clay beds (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report E). The NORCAL interpretation and the televiewer logs were then independently interpreted by at least two geologists to verify the existence of the clay beds. In most cases, clay beds identified on the televiewer logs were visually correlated and verified as clay beds in the rock core. Exceptions to the visual verification were some zones of possible clay that were not recovered in the core and appeared to have been "washed out" during drilling.
Some other possible clay beds noted by examination of televiewer logs corresponded to clayey dolomite or sandstone zones in the core rather than clay beds. Confirmed clay beds identified on the televiewer logs were added to Table 21-2. All the interpreted clay beds were plotted and used to help evaluate bedding orientation and lateral continuity of the clay beds on the cross sections.
In addition, samples of the clay beds were collected for laboratory analysis of physical properties (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report G) and petrographic analysis of lithologic and chemical composition (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Reports J and K). 4.3 Cross Sections The following methodology was used to prepare the geologic cross sections in the ISFSI study area and along the transport route.GEO.DCPP.0 1.21, Rev. 2 December 14, 2001 Page 25 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 7I of 185 1. A topographic profile showing cultural features was drawn based on topographic maps of the ISFSI and Plant Site areas as described in Section 2.2, and shown on Figure 21-6. Several cross sections that extend into areas covered only by the Towill topographic base map were constructed using field-surveyed profiles as described in Section 2.2. 2. All lithologic contacts, structural features, and exploratory boring and trench locations intersecting the cross section alignment were plotted. Boring, and trench locations within 100 feet of the cross section line were extrapolated at a right angle onto the section line using the following guidelines:
no data were projected across faults or fold axes; borings were projected and placed on the cross section at their true elevation unless otherwise noted; trenches were not projected uphill or downhill onto the cross section.
- 3. Surface bedding attitudes within 100 feet of the section line were projected perpendicular to the line of section and plotted as apparent dips. Bedding attitudes from the borings were taken from the table on bedding in the ISFSI borings (Table 21-1) and plotted as apparent dips. The apparent dips were obtained using the apparent dip nomograph from Figure 2-22 of Suppe (1985) and checked using the equation:
tan ot = tan 8 x sin 3 , where ot = apparent dip, 8 = true dip, and 13 = angle between the strike of bed and strike of section (Rowland, 1986). Clay bed attitudes were used to constrain the geometry of bedding with an uncertainty of +/- 5 degrees.
- 4. Contacts between the main stratigraphic units, sandstone (Unit Tofb-2) and dolomite (Unit Tofb-I), as shown in the borings logs were projected into the December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 26 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 2. of 185 cross section. The location, thickness, and dip of friable zones of dolomite and sandstone (Tofb-la, TOfb-2a) in the borings were taken from the table summarizing the friable dolomite and sandstone (Table 21-4). Clay beds were plotted from the table of clay beds (Table 21-2). 5. Information from previous maps and studies were added to the sections after reviewing the data for consistency and quality. This information included pre-excavation topography from the Towill map, geologic stratigraphic and structural data, and subsurface exploration data. Primary sources for this geologic information included studies by Harding Miller Lawson Associates (HML, 1968) and Harding Lawson and Associates (HLA, 1970) and the Diablo Canyon Power Plant FSAR (PG&E, 2000). This information was plotted on the cross sections, as appropriate, in a similar fashion to items 1 to 4 above. 6. Cross section intersections were checked for consistent interpretation, and to provide additional stratigraphic and structural control between cross sections.
In this manner, a single internally consistent interpretation of the three dimensional geology of bedrock was developed for the ISFSI study area and along the transport route. All interpreted clay beds from the borings (Table 21-2) and from the trenches (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report D) were plotted on the geologic cross sections.
The variable thicknesses of the clay beds (Table 21-3) are indicated by different line weights: clay beds thinner than '/8-inch have a thin line weight; I/,- to 1/4-inch-thick beds have a medium line weight; beds thicker than 1/4-inch have a heavy line weight.GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 27 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 21'1 of 185 Similarly, the lateral continuity of clay beds is shown using the following criteria (see Section 5.2.2.4):
Clay beds >1/4-inch thick -extended for 100 feet as a solid line and 100 feet as a dashed line from surface exposure, and to both sides of borings; Clay beds '/8 -to 1/4-inch thick -extended for 50 feet as a solid line and 50 feet as a dashed line from surface exposures, and on both sides of borings; and, Clay beds <1/8 -inch thick -extended for 25 feet as a solid line and 25 feet as a dashed line from surface exposures, and on both sides of borings.
Clay beds are shown with shorter lateral continuity where they are known to be absent in adjoining boreholes or are interpreted to be offset by faults. Bedding attitudes measured in the boreholes are considered "local" or point attitudes because they are measured over only a 4-inch-wide core. As such, they may not record the true regional strike and dip, but may be a local attitude that is anomalous to the regional dip. For example, the attitude of the base of the clay bed at 55.4 feet depth in Boring OOBA-1 (Figure 21-30) is markedly different than the other attitudes in the boring or at the surface. Therefore, this measurement was not used on the cross section for controlling the dip of the strata of clay beds in that area. Where possible, as between borings 01-F and 01-H, distinct lithologic beds were used to establish the dip of the strata. Elsewhere the dips measured in the boreholes and at the surface were compared and assessed for general continuity and the general attitude is used to project strata between borings.
Because the depositional environment for dolomite (Unit Tofb-) is interpreted to be pelagic deep marine (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report L), the clay beds were assumed to have been deposited as laterally continuous GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 28 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page _I of 185 beds. The thickness of the clay beds varies because clays were deposited on irregular erosional surfaces and because subsequent erosion and/or diagenetic differential compaction may have removed or thinned clay in some areas. For example, during deposition on a submarine fan, turbidite pulses of sand associated with sandstone of Unit Tofb-2 may have locally scoured and eroded the deep marine, pelagic clay beds. In the sandstone sequence (Unit Tofb-2), the less frequent clay beds probably represent finer grained tails at the distal ends of the turbidite flows, or the upper fine-grained pelagic "D" and "E" layers in the classic Bouma sequence (Reading, 1981). In cross sections, clay beds were extrapolated between surface exposures and boring control points by projecting lines parallel to bedding strata and, in several constrained areas, parallel to the general facies contact between dolomite (Tofb-.) and sandstone (Tofb-2).
The spacing between projected clay beds was kept constant to reflect uniform bedding thickness in the rock sequence.
In some cases where clay beds encountered in individual borings and surface exposures are at the same stratigraphic level and have similar thickness and character, the clay beds were interpreted to be continuous and were connected between control points for distances up to several hundred feet. We believe that this is a conservative, but reasonable, interpretation.
In other cases, clay beds were not encountered at the projected locations in other borings or surface exposures, and therefore were terminated at some distance away from control points. Some cross sections, such as sections B-B"', C-C' and J-J' (Figures 21-15, 21-16 and 21-23), cross one or more faults that have displaced strata both horizontally and vertically.
Trench and borehole data were not projected across faults onto the cross sections to eliminate problems associated with mismatching of stratigraphy and inaccurate plotting of fault displacement locations.
Other cross sections, such as I-I' and G-G' (Figures 21-22 and 21-20) were drawn within and roughly parallel to the fault blocks so that the continuity of clay beds and other strata such as friable zones, could be interpreted without the complications of significant faulting.GEO.DCPP.01.21.
Rev. 2 December 14, 2001 Page 29 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page $) of 185 Friable zones in the dolomite and sandstone (Units TOfb-la and TOfb-2a, respectively) appear to have limited lateral extent in trenches and surface outcrops.
Therefore, in the cross sections, the friable zones were extended for 50 to 100 feet away from trench or borehole control points as irregular lenses. The distance of projection is related to the thickness of the friable zone, with thicker zones (over about 10-feet thick) having more distant projection than thinner zones. 5.0 ANALYSIS (BODY OF CALCULATION)
Geologic information obtained during this study is shown on a series of geologic maps covering the plant site area (Figure 21-1), the ISFSI study area including the transport route (Figure 21-3), and the ISFSI site (Figure 21-4). Information shown on Figure 21-1 was compiled largely from pre-existing information contained in the FSAR (PG&E 2000), LTSP (PG&E, 1988), and Hall et al. (1979) supplemented by more recent site reconnaissance mapping during the ISFSI site investigations.
Information shown on Figures 21-3 and 21-4 was developed primarily during the ISFSI site investigation.
The geology in the ISFSI study area is complex. Understanding the complexity of the geology and the various geologic processes giving rise to the current geologic conditions is important for interpreting the stratigraphy and structural geology at the site. Below, the geologic processes giving rise to the bedrock complexity are described, followed by an analysis of the stratigraphic and structural relations at the site. 5.1 Bedrock Evolution Bedrock in the ISFSI study area has undergone a complex history of deposition, alteration and deformation.
Based on analysis of surface and subsurface data, supplemented by petrographic analyses of rock lithology, mineralogy, and depositional December 14, 2001 GEO.DCPP.01.2 1, Rev. 2 Page 30 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 33 of 185 history, the following events produced the current lithology and stratigraphic character of bedrock at the site (Figures 21-7 and 21-8): 1. Original deposition
- 2. Diagenesis and dolomitization
- 3. Localized addition of petroliferous fluids 4. Diabase intrusion, hydrothermal alteration, and associated deformation
- 5. Tectonic deformation (folding and faulting)
- 6. Surface erosion and weathering (both chemical and mechanical)
- 7. Borrow excavation and stress unloading This sequence of events is illustrated in Figure 21-7 and described below. The approximate timing of these events is shown on Figure 21-8. (1) Original Depositional Environment Sediments comprising the lithified bedrock in the ISFSI study area were originally deposited in a moderate to deep marine environment, probably on the outer continental shelf or continental slope during the early to middle Miocene. Petrographic analyses show the presence of benthic foraminifera, sponge spicules, and other biogenic material indicative of a moderate to deep marine, pelagic environment.
Deposits consist of a sequence of tuffaceous arkosic and lithic arenitic sandstones and siltstones grading laterally into biogenic chemical limestones and pelagic siltstones.
Thin pelagic clay beds, locally containing foraminifera, occur interbedded with the limestone/siltstone sequence and to a lesser extent within the sandstone sequence.
Deposition of the clay in a moderate to deep marine environment suggests that the clay beds originally blanketed the sea floor and formed laterally continuous beds. The sandstone sequence is interpreted to be a turbidite clastic fan prograding and interfingering with the deep marine quiet water biogenic and pelagic limestone and GEO.DCPP.01.21, Rev. 2 Page 31 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 53 of 185 siltstone sequence (Figure 21-7A). The ISFSI study area straddles the gradational facies contact between these two depositional environments.
The turbidite sequence represents high-energy submarine debris flows that have reworked pyroclastic tuffaceous shallow marine deposits out onto the outer continental shelf or continental slope. Turbidite sediment was derived from continental erosion and volcanism, and consisted of mixtures of older terrigenous debris and volcanic airfall tuff and ash and alluvially-transported debris. The lesser amounts of clay in the turbidite sequence probably reflects localized erosion and scour of the clay deposits by the high-energy turbidite flows. Borehole data at the ISFSI study area clearly show an upward textural facies change from a relatively coarse sequence of sandstone to relatively fine sequence of limestone and siltstone (now dolomite).
This depositional facies change is illustrated on the upper part of Figure 21-7A. Bedding ranges from thinly bedded (less than 'A-inch thick) to massively bedded (greater than 5 feet thick). Bedding generally is better developed and/or preserved in the limestone/siltstone sequence and less well developed and/or preserved in the sandstone sequence.
(2) Diagenesis and Dolomitization Following deposition and burial, the entire depositional sequence was subjected to diagenesis and chemical replacement and recrystallization by a process called dolomitization (illustrated in Figure 21-7B). The degree of dolomitization varies markedly over short distances and was apparently influenced by grain size and permeability differences in the original sediments.
In this process, the finer-grained limestone is completely or nearly completely recrystallized to crystalline dolomite, siltstone is strongly to moderately recrystallized, and sandstone is moderately to weakly recrystallized with localized beds of strongly recrystallized dolomite and localized beds of less-dolomitized friable sandstone.
All the rock types, siltstone, sandstone and limestone, maintain their original relict textures to some extent as individual grains of GEO.DCPP.0 1.21, Rev. 2 Page 32 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page W of 185 plagioclase and clastic material were replaced with dolomite.
The process of dolomitization locally obscures bedding and in places makes lateral correlation of individual beds between boreholes very difficult.
During diagenesis many clastic and plagioclase grains were altered to clay. In some cases, the clay was partially dolomitized; in other cases the clay is not dolomitized.
Dolomite replacement increased the degree of cementation in the finer-grained rocks of the dolomite (Unit Tofb-.), and as a result these rocks are somewhat stronger and more brittle than the sandstone (Unit Tofb-2), which typically has less cementation.
The process of dolomitization may have been influenced by, or caused by, hydrothermal activity associated with the emplacement of shallow diabase intrusions in the site area. Diabase intrusion and hydrothermal activity is described in process 4 below. (3) Localized Addition of Petroliferous Fluids Zones of hydrocarbon accumulations are locally preserved throughout the rock sequence at the ISFSI study area, but preferentially within the dolomite.
Black, sticky hydrocarbon films also were observed on fractures and within faults in some of the exploratory trenches (e.g., Trench T-20A, William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report D). The origin or source rock of the hydrocarbons is not known. It may be that during or after the process of dolomitization, diagenesis of the bioclastic fraction of the rock at the site caused the mobilization and localized deposition of hydrocarbons.
The areas of hydrocarbon accumulation occur in patches or splotches within the rock mass as well as concentrated along some faults and joints, and are not confined to individual beds, showing that at least some migration of the hydrocarbons has occurred.
The patches of hydrocarbons commonly crosscut bedding, and tend to stain and obscure the stratigraphic relationship.
These patches of hydrocarbons are shown diagrammatically on Figure 21-7B.GEO.DCPP.0 1.21, Rev. 2 December 14, 2001 Page 33 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page J_ of 185 (4) Diabase Intrusion, Hydrothermal Alteration, and Associated Deformation Locally, hypabyssal shallow intrusions of diabase invaded the dolomitic sandstone, siltstone, and dolomite of the Obispo Formation as illustrated in Figure 21-7C. Petrographic analyses show that the diabase is primarily an altered cataclastic gabbro and diorite. Radiometric dates on similar diabase elsewhere in the Irish Hills indicate that the intrusions are middle Miocene in age (Hall et al., 1979). The diabase occurs as sills, dikes, and larger, massive intrusive bodies. The diabase is locally exposed along Diablo Canyon Creek beneath the eastern part of the Raw Water Reservoir and along the northern margin of the canyon walls. Prior to the 1971 excavation of the borrow cut area, a large diabase sill in the Obispo sandstone and dolomite was present in the raw water reservoir area (Figure 21-14) (HLA, 1968). This body of diabase was entirely removed during the borrow excavation, and no diabase was observed in the ISFSI study area or along the transport route during surface mapping and subsurface exploration.
However, the feeder vent for the now-removed diabase sill has not been identified and possibly it or other intrusions may underlie the ISFSI site. Hydrothermal solutions associated with the diabase intrusion locally altered the diabase and probably altered the surrounding wall rock. Petrographic analyses of the diabase show clear evidence of hydrothermal alteration (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report J). As mentioned above, the intrusion of diabase and associated hydrothermal activity also may have caused or influenced the process of dolomitization in the site area. Intrusion of the magnesium-rich diabase would have caused circulation of natural occurring magnesium-rich seawater or hydrothermal fluids rich in magnesium from the diabase in the surrounding wall rock. Partial replacement of the calcium by magnesium in the limestone, calcareous sandstone and siltstone may have produced the observed dolomite.
Possible hydrothermal "dolomitization" of the bedrock is supported by the following observations:
GEO.DCPP.01.21, Rev. 2 Page 34 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page V- of 185"* Hall et al. (1979) do not map or describe dolomite in the Obispo Formation in the plant site region (10 kilometer radius), thus, the dolomite appears to be localized in the vicinity of the diabase intrusion in Diablo Canyon. " The diabase clearly was altered by late-phase hydrothermal solutions demonstrating the presence of hydrothermal activity. " Petrographic analyses show the presence of zeolite and rare clays within the dolomitic sandstone and dolomite (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report J) suggesting hydrothermal activity may have produced low-grade metamorphic changes in the host rock. " The diabase is magnesium-rich and is a possible source of magnesium to replace calcium in the dolomitization process. Alternatively, the intrusion may have driven magnesium-rich seawater, the most common source of magnesium for dolomitization, through the rocks by thermal convection.
Intrusion of the diabase also may have been accompanied by magmatic stoping and/or localized uplift, warping and faulting of the bedrock. This localized deformation is diagrammatically illustrated on Figure 21-7C. Local uplift (or doming) of the bedrock may be the cause of the change in bedding attitudes observed on the lower half of the slope above the ISFSI site (described in the Analysis section below), and possibly formed or modified joints in the bedrock.
(5) Tectonic Deformation (Folding and Faulting)
Subsequent to the diabase intrusions in the middle Miocene, bedrock in the ISFSI study area was tectonically folded and faulted (Figure 21-7D) as part of the regional deformation that formed the Pismo syncline (Hall et al., 1979). The tectonic faulting and folding deformed the bedding and facies contacts within the sandstone/dolomite sequence.
Folding of the facies contact, as well as the bedding, complicates the interpretation and correlation of bedrock stratigraphy at the site.GEO.DCPP.01.21, Rev. 2 Page 35 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 31 of 185 This area-wide tectonic deformation is superimposed on the earlier localized intrusive deformation from the diabase described above. In addition, the tectonic deformation may have been locally influenced by the more ductile rheology of the diabase. The ISFSI study area is situated on a northwest-trending syncline/anticline couplet (Figures 21-3, 21-4). The syncline/anticline couplet forms tight folds with steep limbs of up to 50 to 70 degrees directly south of the ISFSI site but transitions into folds with broad crests and gentle limbs of 5 to 20 degrees across the ISFSI site as the fold axes approach the former area of the diabase intrusion.
This change in structure may be the result of tectonic deformation superimposed on the earlier intrusive "doming", or it may reflect the more ductile behavior of the diabase intrusion, or it may be simply a change in tectonic deformation without any influence from the diabase intrusion.
In addition to folding, a zone of northwest-trending minor faults disrupts the bedrock stratigraphy in the ISFSI study area (e.g., cross section B-B"', Figures 21-15 and 21-32). The faults are high-angle and slickensides indicate strike-slip to oblique strike-slip displacement.
As shown on Figure 21-15, northeast-side down, vertical separation of at least 50 feet, occurs across the fault zone over a width of about 200 feet. Given the northwest dip of bedding, this sense of vertical separation can be produced by pure right lateral strike slip or by a component of oblique right slip. The strike slip displacement juxtaposes stratigraphic units of different thicknesses and lithologies.
The strike slip displacement also complicates the interpretation and correlation of bedrock lithology, bedding, and facies changes in the lower part of the slope and offsets the axis of the small anticline across the site. (6) Surface Erosion and Chemical Weathering During the past 1 million years, the ISFSI study area and transport route has been exposed to marine, fluvial and hillslope erosion. Remnants of marine deposits and hillslope colluvium are preserved locally in the ISFSI study area where they were not removed during excavation of the borrow area in 1971.GEO.DCPP.01.21, Rev. 2 Page 36 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page S%_ of 185 Infiltration of surface water and groundwater migration has chemically weathered and altered the bedrock. The degree of surface weathering decreases with progressive depth beneath the site and occurs preferentially and penetrates more deeply along fractures, joints and faults as shown in Figure 21-7E. The 1971 borrow excavation at the ISFSI site area removed the surficial soil and a variable thickness of bedrock from the site, with up to 100 feet of rock removal above the ISFSI pads (cross sections A-A' and B-B"'; Figures 21-14 and 21-15). The original ground surface was a resistant bedrock spur ridge that had been subjected to weathering for a substantial time period, and had developed a weathered zone penetrating an unknown depth into the rock mass. As a result, the rock now exposed in the central part of the borrow excavation that was considerably below the former ground surface is less weathered than the rock along the margins of the borrow excavation where excavation was shallower.
Additional minor weathering has occurred within the rock exposed after the borrow excavation was completed, but this "secondary" zone of weathering is the result of only about 30 years of exposure, as opposed to the many tens to hundreds of thousands of years of exposure for the original bedrock surface.
The surface weathering is superimposed on the pre-existing hydrothermal alteration, petroliferous alteration and dolomitization as shown on Figure 21-7E. The combination of alteration products (to varying degrees of development) significantly masks the primary depositional lithology and bedding, and complicates the interpretation of depositional origin. (7) Borrow Excavation and Stress Unloading Rock removal associated with the borrow excavation decreased the lithostatic stress on the bedrock currently exposed at the site (Figure 21-7F). Since then, stress unloading has caused shallow localized dilation of the rock mass, and the opening of joints, fractures and other discontinuities.
This shallow dilation of the rock mass tends to mask bedding, so differentiating bedding from joints and fractures in the bedrock is difficult in surface exposures and exploratory trenches.GEO.DCPP.0 1.21, Rev. 2 Page 37 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page _3 of 185 5.2 Stratigraphic Analysis Bedrock in the ISFSI study area and along the transport route is differentiated into distinct, mappable lithologic units taking into account the complex depositional history and alteration of the rock mass. The following sections describe this stratigraphy.
5.2.1 General
Stratigraphy Sandstone and dolomite bedrock in the ISFSI study area and along the transport route belongs to the fine-grained member of the early to middle Miocene Obispo Formation (Tof) as mapped by Hall et al. (1979). Mapping of the DCPP plant site area differentiated three subunits (Units Tofa, Tofb, Tofr) of the fine-grained member of the Obispo Formation (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report A). As shown on Figure 21-1, Unit Tofa occurs in the eastern part of the plant site area (entirely east of the ISFSI study area) and consists primarily of thick to massively bedded diatomaceous siltstone and tuffaceous sandstone.
Unit Tofb occurs in the central and west-central part of the DCPP plant site area, including the entire ISFSI study area, the upper part of the transport route and beneath the power block, and consists primarily of medium to thickly bedded dolomite, dolomitic siltstone, dolomitic sandstone, and sandstone.
Unit Tofr occurs in the western part of the plant site area beneath the lower part of the transport route and consists of thin to medium bedded, extensively sheared shale, claystone and siltstone.
In addition, locally extensive areas of diabase intrusive rocks were mapped along the northern margin of Diablo Canyon Creek and locally below the raw water reservoir (Unit Tvr). 5.2.2 ISFSl Study Area Stratigraphy In the ISFSI study area, Unit Tofb is further divided into a dolomite subunit (Tofb-.) and a sandstone subunit (Tofb-2).
For ease of discussion, these subunits are referred to as Units Tofb-l and Tofb-2. Figure 21-5 provides a generalized stratigraphic column illustrating the distribution of rock types within these two subunits.
Unit Tofb-j consists primarily of dolomite, dolomitic siltstone, fine-grained dolomitic sandstone, and limestone.
Unit GEO.DCPP.01.21, Rev. 2 Page 38 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page '_V of 185 Tofb-2 consists primarily of medium to coarse-grained dolomitic sandstone and sandstone.
Figures 21-9 to 21-12 provide summary logs of all the borings drilled in the ISFSI study area during the ISFSI site investigation.
These summary logs show the primary lithologic units and clay beds greater than 1/4-inch thick. Additional thinner clay beds encountered in the borings are listed in Table 21-3. These data were used together with surface geologic data to construct 12 cross sections across the study area (Figures 21-13 to 21-25). The contact between Units Tofb.1 and Tofb-2 marks a facies change from the deep marine dolomite sequence to the sandstone turbidite sequence.
The contact varies from sharp to gradational and bedding from one unit locally interfingers with bedding of the other unit. For purposes of mapping, we arbitrarily place the contact at the first occurrence (proceeding down section) of medium to coarse-grained dolomitic sandstone.
As shown on the cross sections, the interfingering nature of the dolomite/sandstone contact beneath the ISFSI study area can be interpreted.
This relationship is shown on cross sections A-A', B-B"', C-C', and I-I' (Figures 21-14, 21-15, 21-16, and 21-22, respectively).
Some of the thin interfingering beds provide direct evidence for the lateral continuity and geometry (i.e., attitude) of bedding within the hillslope (for example, between boring 01-F and OOBA-1 on section I-I'). Analysis of the cross sections shows that the facies contact between Units Tofb.1 and Tofb-2 generally extends from northwest to southeast across the ISFSI study area, with sandstone of Unit Tofb-2 primarily in the north and northeast part of the area and dolomite of Unit Tofb-I primarily in the south and southwest part of the area. The three dimensional distribution of the facies contact is well illustrated by comparing cross sections B-B"' and I-I' (Figures 21-15 and 21-22, respectively).
This distribution of the two units indicates that the source area of sandstone turbidite sequence lay to the northeast and the moderate to deep marine basin lay to the southwest.
In addition, we recognize two different transgressions of the dolomite of Unit Tofb-, an upper transgression or tongue of dolomite and a lower transgression of dolomite.
The GEO.DCPP.01.21, Rev. 2 Page 39 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page k-j of 185 upper transgression of dolomite and its contact with the underlying sandstone, as described above, is well documented in the borings, trenches and surface outcrops as shown on Figures 21-4 and 21-22. The south-southwestern extent of the underlying sandstone facies is indicated by borehole 01-I (Figure 21-22), which penetrated a thick sequence of dolomite and documents the absence of sandstone above the elevation of the borehole bottom. The lower transgression or tongue of dolomite that underlies the sandstone is exposed in the roadcut along Reservoir Road in the vicinity of Parking Lot 8. Based on the occurrence of calcareous siltstone and locally abundant foraminifera in boreholes beneath the power block, the lower transgression of dolomite is inferred to extend beneath the power block as shown on cross sections B-B"' and C-C' (Figures 21-15 and 21-16, respectively).
During initial stratigraphic analysis, depositional facies within each of the two subunits were further differentiated:
Unit Tofb-. was divided into facies A (dolomite) and B (dolomitic siltstone);
while Unit Tofb.2 was divided into facies C (dolomitic sandstone) and D (sandstone).
These additional facies contacts were used to help evaluate the internal stratigraphy within each subunit and to understand the depositional environment of the bedrock. After thorough analysis of all the borings and surface outcrops, these additional facies (A, B, C, D) contacts could not be confidently mapped across the ISFSI study area; thus, we do not show these units on the summary boring logs or on the cross sections.
However, boring logs in William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report B contain these facies designations for reference.
5.2.2.1 Dolomite (Unit Tofb-1) The slope above the ISFSI site, including most of the 1971 borrow area excavation slope, is underlain by dolomite (Figure 21-4). The dolomite is exposed as scattered outcrops across the excavated slope, along the unpaved tower access road, in the upper part of most borings in the ISFSI study area (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report B), and in most exploratory trenches (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report D). The dolomite consists predominately of tan to yellowish-brown, competent, well-bedded dolomite, with GEO.DCPP.01.21, Rev. 2 Page 40 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 4O-of 185 subordinate dolomitic siltstone to fine-grained dolomitic sandstone, and limestone (Figure 21-34). Petrographic analyses of hand and core samples from, and adjacent to, the ISFSI study area show that the rock is primarily carbonate (dolomite) with a variety of secondary components.
The petrographic analyses show that the rock consists primarily of clayey dolomite, altered clayey carbonate and altered calcareous claystone, with lesser amounts of clayey fossiliferous, bioclastic and brecciated limestone, fossiliferous dolomite, and altered sandstone and siltstone (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report J, Tables J-1 and J-2). X-ray diffraction analyses show that the dolomite has about 25% quartz, 8% feldspar, 40 to 50% dolomite (including some calcite), a few percent clays, and 15 to 20% amorphous material (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report J, Table J-3). As described in the petrographic analysis, the carbonate component of these rocks is primarily dolomite; thus we use the general term dolomite and dolomitic sandstone to describe the rock. The dolomite crops out on the excavated borrow area slope as flat to slightly undulating rock surfaces.
The rock is moderately hard to hard and typically medium strong to brittle, with locally well-defined bedding that ranges between several inches to 10 feet thick in surface exposures and boreholes.
Bedding planes are laterally continuous for several tens of feet as observed in outcrops, and may extend for hundreds of feet based on the interpreted marine depositional environment.
The bedding planes are generally tight and bonded. Unbonded bedding parting surfaces are rare and generally limited to less than several tens of feet based on outcrop exposures.
5.2.2.2 Sandstone (Unit Tofb-2) Strata of the sandstone Unit Tofb-2 generally underlies the ISFSI study area below about elevation 330 feet (Figure 21-4). Typically, the rocks in this subunit are well-cemented, hard sandstone and dolomitic sandstone and lesser dolomite beds, as encountered in the lower part of borings 98BA-1, OOBA-2 and OOBA -3, and in borings CTF-A, 01-A, 01-B, 01-C, 01-D, 01-E, 01-F, 01-G and 01-H (Figures 21-9 to 21-12).GEO.DCPP.01.21, Rev. 2 Page 41 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page,'O of 185 The well-cemented sandstone encountered in the borings and trenches is tan to gray, moderately to thickly bedded, and competent (Figure 21-35). The rock is well sorted, fine to coarse-grained, and is typically moderately to well-cemented with dolomite.
The rock is of low to medium hardness and medium strength.
Petrographic analyses show that the sandstone is altered, and that its composition varies from arkosic to arenitic, with individual grains consisting of quartz, feldspar, and dolomite and volcanic rock fragments (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report J). The matrix of some samples contains a significant percentage of carbonate and calcareous silt to clay matrix (probably from alteration).
X-ray diffraction analyses show that the sandstone is about 20% quartz, 15 to 20% feldspar, 15% dolomite (with some calcite), and about 40% clay (10% kaolin and 30% smectite);
one sample (P-21) is dominantly clastic dolomite with only 7% quartz and about 15% clays (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report J, Table J-3). Petrographic and x-ray analyses show that the carbonate is primarily dolomite.
Thus, these rocks are referred to as sandstone and dolomitic sandstone.
Bedding in places is well defined, and bedding plane contacts are tight and well bonded. Similar to the dolomite beds, unbonded bedding surfaces within the sandstone are rare and generally limited to less than several tens of feet based on limited outcrop exposure.
5.2.2.3 Friable Bedrock Distinct zones of friable bedrock are present within the generally more cemented sandstone and dolomite (Figures 21-4 and 21-32; Table 21-4). In some cases, the friable bedrock appears to reflect the original deposit without subsequent dolomitization.
In other cases the friable bedrock appears to be related to subsequent chemical weathering, and/or hydrothermal alteration.
All friable beds within Units Tofb-I and Tofb-2 are designated with the subscript (a). Unit TOfb-.a consists primarily of altered-or-weathered dolomite or dolomitic siltstone that has block-in-matrix friable consistency or simply a silt and clay matrix with friable consistency.
The friable rock is of low hardness and is very weak to weak. X-ray diffraction analyses show the friable dolomite to have about 20% quartz, 10% feldspar, GEO.DCPP.01.21, Rev. 2 Page 42 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page .t of 185 50% dolomite that is about half composed of a poorly crystalline phase, and 16% clay (mostly smectite) (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report J, Table J-3). The primary differences between the dolomite and friable dolomite is the poorly crystalline phase and a higher percentage of clay, both are probably caused by weathering or alteration of the dolomite.
Unit TOfb-2a consists primarily of friable sandstone, is of low hardness, and is very weak to weak. X-ray diffraction analyses show the friable sandstone has about 15% quartz, 10% feldspar, 15 to 20% dolomite (including some calcite), and 50 to 60% clay (10% kaolin, 50% smectite);
one sample (P-21) is dominantly a clastic dolomite with only 7% quartz and about 15% clay (Diablo Canyon ISFSI Date Report J, Table J-3). The friable sandstone exhibits a somewhat lower feldspar content and a higher percentage of clays than the non-friable sandstone.
In many cases, the friable sandstone is the original sandstone that has been chemically weathered or altered to a clayey sand (i.e., plagioclase and lithics altered to clay). In other cases, the friable sandstone simply lacks dolomite cementation and retains its original friable nature. The friable zones in the dolomite and sandstone are known from exposures in the trenches and in the borings to be limited vertically and laterally in their extent. The vertical thickness of the friable rock encountered in borings ranges from less than 1 foot to 32 feet; the thickest friable zones were encountered in Boring OOBA-2 (Figures 21-9 through 21-12). The friable zones extend laterally for tens of feet in trench exposures, and were correlated up to about 200 feet between borings. As illustrated on the cross sections (e.g., I-I', J-J') the zones of friable rock appear more common, and possibly more laterally continuous, in the sandstone than in the dolomite.
Friable beds were observed between beds of competent cemented sandstone and/or dolomite in exploratory trenches in the ISFSI pads area. Based on trench exposures and borehole correlations, friable zones are more laterally continuous in a direction along bedding than across bedding.
Some thin, irregular friable zones or zones of weak rock were observed along and parallel to joints and faults. These zones do not appear to be as laterally continuous or thick as the bedding-parallel friable zones, and are not shown on cross sections.GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 43 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 4-S of 185 5.2.2.4 Clay Beds Clay beds are present within both the sandstone and dolomite subunits in the ISFSI study area (Table 21-3). The clay beds were observed in several trenches (Figure 21-36) and in many of the borings (Table 21-2; Figures 21-29, 21-30, and 21-31). Because these clay beds are potential layers of weakness in the hill slope above the ISFSI site they were investigated in detail. The clay beds generally are bedding-parallel and commonly range in thickness from thin partings (<1/16-inch thick) to beds up to 2 to 4 inches thick; the maximum thickness encountered was approximately 81/2 inches in Boring 0OBA1. Two thirds of the clay beds encountered in the borings are less than 1/4-inch thick; in contrast, about two-thirds of the clay beds exposed in the trenches are greater than 1/4-inch thick (Table 21-3). This difference in thickness between the borings and trenches, however, probably reflects our ability to better recognize and document very thin clay beds in the rock core than in the trenches, rather than a true stratigraphic change between surface and subsurface exposures.
The clay beds are yellow-brown, orange-brown, and dark brown, sandy and silty, and stiff to hard. Petrographic analyses show that the clay contains marine microfossils and small rock inclusions; the rock inclusions are angular pieces of dolomite that are matrix-supported, and have no preferred orientation or shear fabric (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report K). In the trenches, the clay beds locally have slickensides and polished surfaces.
The clay beds typically appear to be overconsolidated (because of original burial), and, where thick, have a blocky structure.
The clay beds encountered in the borings are recorded on the boring logs. In addition, in most of the borings, the clay beds were also documented in situ by a borehole televiewer.
The televiewer logs show that the clay beds generally are in tight contact with the bounding rock and are bedding-parallel.
The clay beds range from massive with no preferred shear fabric, to laminated with clear shear fabric. The shear fabric is interpreted to be the result of tectonic shearing during folding and flexural slip of the bedding surfaces; the shear fabric does not reflect gravitational sliding because features indicative of large-scale rock slides, such as disarticulation of the rock mass, lack of bedding GEO.DCPP.01.21, Rev. 2 Page 44 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page -1. of 185 continuity or change in bedding orientation, tensional fissures and geomorphic expression of a landslide on pre-construction air photos, are not present.
Clay Beds in Dolomite.
Clay beds are more frequent, thicker and more laterally continuous in the dolomite (Unit Tofb-i). Examination of the continuity of clay beds within, and between, adjacent trenches, road cuts, and borings provided data on the lateral continuity (persistence) of the clay beds. Individual clay beds exposed in the trenches and road cuts appear to be persistent over distances of between tens of feet to over 160 feet, extending beyond the length of the exposures.
The exposed clay beds are wavy and exhibit significant variations in thickness along the bed. Thinner clay beds (less than about 1/4-inch thick) typically contain areas where asperities on the surfaces of the bounding adjacent hard rock project through or into the thin clay. The bedding surfaces also commonly are irregular and undulating with the height (amplitude) of the undulation greater than the thickness of the clay bed such that the clay beds likely have local rock-to-rock contact that increases shear strength along clay bed interfaces to a greater value than that of the clay itself. This would increase the average shear strength of the clay bed surface for analyses of potential sliding along these interfaces.
For example, the clay bed exposed in Trenches T- 1 4A and T- 1 4B extends for about 160 feet, including the length of Trench T-14, the adjacent roadcut exposure, and correlation to the clay exposed Trench T-19. The thickness of this clay varies from about 4 inches in Trench T-14 and decreases to about 1/4-inch in Trench T-19 where the clay splays into several thin clay beds. Many of the clay beds appear to correlate between outcrops and borings. For example, the clay bed in Trenches T- 11 and T-12 appears to correlate over a distance of about 100 feet. Other correlations are shown on cross section I-I' (Figure 21-22). These correlations indicate that at least some clay beds extend over several hundred feet into the hillslope.
However, some beds clearly do not correlate; for example, the clay beds exposed in Trenches T-14 and T-15 are not found in nearby Boring 01-I. The interpreted lateral continuity of clay beds is best illustrated on cross section I-I' (Figure 21-22).GEO.DCPP.0 1.21, Rev. 2 December 14, 2001 Page 45 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page A-1 of 185 Clay Beds in Sandstone.
Clay beds are less frequent, generally thinner, and less laterally continuous in the sandstone (Unit Tofb-2). As shown on Table 21-3, clay beds in the sandstone generally are less than 'A-inch thick. These thinner clay beds are difficult to correlate laterally between borings and, at least locally, are less than 50 to 100 feet in lateral extent. For example, as shown on cross sections B-B"' and I-I', (Figures 21-15 and 21-22, respectively), clay beds were not encountered in Boring 01-B but were encountered in adjacent borings 50 to 100 feet away (i.e., Borings 01-A and 01-H). Consequently, we interpret that the clay beds in the sandstone generally are thin (i.e., less than 1/4/4-inch thick) and have lateral continuity of less than 100 feet in the ISFSI site area. Clay Moisture Content. The clay beds encountered in the borings and trench excavations in both the dolomite and sandstone were moist. Clay beds uncovered in the trenches that dried out after exposure during the dry season, became hard and desiccated.
When wetted during the rainy season, the clay in the trenches became soft and sticky; possible local perched water tables (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report B) also may soften the upper portions of the clay beds during the rainy season in the ISFSI site area. Clay Composition.
X-ray diffraction analyses (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report K) show that the clay-size fraction of the clay beds in Trenches T-1 1A, T-14A, T-14B, and T-15 consists of three primary minerals:
kaolinite (a clay), ganophyllite (a zeolite), and sepiolite (a clay). The silt-size fraction of the sample consists primarily of rock and mineral fragments of quartz, dolomite/ankerite, and calcite.
Petrographic examination of the clay (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report K) shows a clay matrix with matrix-supported angular rock fragments and no shear fabric. Included rock fragments have evidence of secondary dolomitization of original calcite (limestone), and localized post-depositional contact alteration.
Some samples contain microfossils (benthic foraminifera).
The ganophyllite minerals appear to be expansive, as evidenced by swelling of one sample (X-1 from Trench T-14A) after thin-section mounting.
Sample X-2 also had a significant GEO.DCPP.01.21, Rev. 2 Page 46 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page At of 185 percentage of ganophyllite, and a high plasticity index (PI) of 63 (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Reports K and G, respectively).
The presence of microfossils confirms that the clay is depositional in origin and was not formed by alteration or weathering of a lithified host rock. Therefore, the clay is interpreted to reflect pelagic deposition in a marine environment.
5.3 Structural
Analysis Bedrock in the ISFSI study area has been deformed by tectonic processes and possibly by intrusion of diabase. The detailed stratigraphic framework described above provides the basis for analyzing the geologic structure in the site area. Geologic structures in the ISFSI study area include folds, faults, and joints and fractures.
Understanding the distribution and geometry of these structures is important for evaluating rock mass conditions and slope stability for two reasons: (1) folds in the bedrock produce the inclination of bedding that is important for evaluating the potential for out-of-slope bedding-plane slope failures; and (2) faults and, to a lesser extent, joints in the bedrock produce laterally continuous rock discontinuities along which potential rock failures may detach in the proposed cutslopes.
The distribution and geometry of folds and faults in the bedrock were evaluated by detailed surface geologic mapping, trenches, and borings. Data from these studies were integrated to produce geologic maps (Figures 21-1, 21-3, and 21-4) and geologic cross sections (Figures 21-13 to 21-24). Cross sections were prepared oriented both down slope and parallel to slope to evaluate the three-dimensional distribution of structures.
Bedding attitudes were obtained from surface mapping (including road cut and trench exposures) and from boreholes (based on visual inspection of rock core integrated with oriented televiewer data). Bedding attitudes from surface mapping are shown on the geologic maps. Bedding attitudes from boreholes are compiled in Table 21-1. All of GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 47 of 181!
Calculation 52.27.100.731, Rev. 0, Attachment A, Page 11 of 185 these bedding attitudes were used to constrain the distribution of bedrock lithologies and geometry of bedding shown on the cross sections as described earlier.
5.3.1 Folds
As shown on the geologic maps (Figures 21-1, 21-3 and 21-4) and cross sections (Figure 21-15, 21-16, 21-17 and 21-19), bedrock in the ISFSI study area is deformed into small northwest-trending synclines and anticlines along the western limb of the larger regional Pismo syncline (Figure 21-37). On the ridge southeast of the ISFSI study area, nearly continuous outcrops of resistant beds define an anticline and two en echelon synclines (Figures 21-1 and 21-3). These folds, which are relatively tight and sharp-crested with steep limbs, plunge to the northwest.
Within the ISFSI study area, a northwest-plunging anticline appears to represent the northwestward continuation of the anticline that is exposed in the ridgetop near the Skyview Road overlook (Figure 21-1). The anticline varies from a tight chevron fold southeast of the ISFSI study area to a very broad-crested open fold across the central part of the study area. The northwestward shallowing of dips along the anticlinal trend appears to reflect a flattening of fold limbs up section. In the ISFSI study area, the broad crest of the fold is offset and disrupted by series of fold-parallel, minor faults (Figure 21 15). The minor faults offset the fold axis as well as produce local drag-folding, which tends to disrupt and complicate the fold geometry.
The axis of this broad-crested anticline is approximately located on the geologic map (Figure 21-4) where it best fits the data. The en echelon syncline found at the ridge crest along Skyview Road projects to the northwest along the southwestern margin of the ISFSI study area. In this area, the syncline transitions into an en echelon northwest-trending monocline and syncline (Figures 21-1 and 21-3). In the ISFSI study area, the syncline opens into a broad, gently northwest-plunging (generally less than 15 degrees) fold with gently sloping limbs (generally less than 20 degrees).
Bedding generally dips downslope to the northwest in the upper part of the slope above the ISFSI site and parallel to the slope to the southwest GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 48 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 50 of 185 and west in the lower part of the slope. Minor undulations in the bedding reflect the transition from a tight syncline to a relatively flat monocline, or "shoulder", and then back to a broad northwest-plunging syncline.
These localized interruptions to the northwest plunge of the fold may be caused by the diabase intrusion and localized doming associated with the intrusion (compare Figures 21-7c and 7d). Understanding the location, geometry and characteristics of the syncline at the site is important for evaluating bedrock beneath the power block and establishing a correlation of bedrock between the power block and the ISFSI site. As discussed above and shown on cross sections B-B"', C-C', D-D', E-E', and F-F' (Figures 21-15 to 21-19), the western limb of the small syncline varies from steeply dipping (approximately 70 degrees northwest) across the southern part of the plant site area to gently dipping (approximately 30 degrees northwest) beneath the power block. This change in dip of the syncline across the plant site mirrors the change in dip described above across the ISFSI site area. Based on the geometry of the syncline, bedrock beneath the power block consists of sandstone of Unit Tofb-2 underlain by the lower body of dolomite of Unit Tofb-1 (cross sections B-B"' and C-C', Figures 21-15 and 21-16, respectively).
The power block is located on the same stratigraphic sequence that is exposed at the ISFSI site, but is approximately 400 feet lower in the stratigraphic section. As shown on cross section B-B"', boreholes drilled during foundation exploration for the power block encountered calcareous siltstone with abundant foraminifera.
This description of the rock is very similar to the dolomite of Unit Tofb-l; thus, we interpret the lower contact between Units Tofb-I and Tofb-2 to be present beneath the power block area. Folding at the site occurred during growth of the northwest-trending regional Pismo syncline in the Pliocene to early Quaternary (PG&E, 1988). The smaller folds at and near the ISFSI site area are parasitic secondary folds along the southwest limb of the larger Pismo syncline.
Because of their structural association to the Pismo syncline, we infer that the folding at the site also occurred during the Pliocene to early Quaternary
.GEO.DCPP.0 1.21, Rev. 2 Page 49 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 51 of 185 (Figure 21-8). Some deformation may have accompanied the earlier Miocene diabase intrusions.
5.3.2 Faults
Numerous minor, bedrock faults occur within the ISFSI study area (Figures 21-1, 21-4, 21-32, and 21-33). Based on offset lithologic and bedding contacts, most of the faults show vertical separations of a few inches to a few feet. At least five faults show vertical separation of several tens of feet. Slickensides and mullions on the fault surfaces generally show strike slip to oblique strike slip displacement (Table 21-5; Figure 21-38). The primary faults trend northwest, subparallel to the local fold axes (Figure 21-38). They dip steeply to near-vertical, generally 70 to 90 degrees, both northeast and southwest (Table 21-5). They consist of interconnecting and anastomosing strands, in zones up to 5 feet wide. The primary faults have documented lengths of tens of feet to a few hundred feet, and are spaced from several tens of feet to hundreds of feet apart across the ISFSI site area based on trench exposures and surface geologic mapping.
Secondary faults have variable trends and inclinations.
They have very small displacements, generally less than a few inches. Some secondary faults splay off of the primary faults, or form part of the primary fault zone, such as in trench T- 1 and T- 17. Others are far from primary faults, such as those in trenches T-1 A, B, C and D, T-14B and T-15. The fault surfaces within bedrock vary from tightly bonded or cemented rock/rock surfaces, to relatively soft slickensided clay/rock and clay film contacts.
Individual faults are narrow, ranging in width from less than an inch to about 2 feet. Fault zones contain broken and slickensided rock, intermixed clay and rock, and locally soft, sheared, clayey gouge. The thickness of fault gouge and breccia is variable along the faults. Cross section B-B"' (Figure 21-15) shows the subsurface stratigraphy and structure beneath the ISFSI pads. As shown on the map (Figure 21-4) and cross section, five GEO.DCPP.01.21, Rev. 2 Page 50 of 181 December 14. 2001i Calculation 52.27.100.731, Rev. 0, Attachment A, Page S7. of 185 minor faults clearly juxtapose the dolomite (Tofb-) against the sandstone (Tofb-2) and truncate individual friable beds. Vertical separation across individual faults ranges from about 10 feet to greater than 50 feet based on displacements of friable beds and the contact between Units Tofb-1 and Tofb-2. Total vertical separation across the entire fault zone exceeds 50 feet. As described previously, the contact between Units Tofb-1 and Tofb-2 beneath the pads is based on the first occurrence of medium to coarse-grained sandstone, and there is no evidence of significant facies interfingering between the two units beneath the pads that would obscure the amount of offset. Therefore, the interpretation of vertical separation of bedrock along the faults is given a relatively high degree of confidence.
Subhorizontal slickensides indicate that the minor faults in the ISFSI site area have predominantly strike slip displacement (Table 21-5, Figure 21-39). Using a typical range of 10-20 degree rake on the slickensides and the vertical separation, total fault displacement is estimated to be several tens to several hundreds of feet. The faults trend subparallel to the axis of the Pismo syncline and trend approximately 35 to 55 degrees more westward than the offshore Hosgri fault zone (Figure 21-38). The faults at the ISFSI site area may be continuous with several other minor faults exhibiting similar characteristics exposed along strike in dolomite in the Diablo Creek roadcut about 800 feet to the north (Figures 21-1, 21-3, and 21-38). Given this correlation and the presence of several hundred feet of strike slip displacement, we infer that the faults may be at least several thousand feet long. However, the correlation between faults exposed within the ISFSI site and the roadcut along Diablo Creek, assumes that the slopes northwest of Diablo Creek are in place and have not been translated or rotated down slope as the result of landsliding.
Although not conclusive, some geomorphic evidence suggests the presence of an ancient landslide in this area north of Diablo Creek. If the roadcut exposure is part of a landslide mass then the faults would not correlate to the same minor faults found in the ISFSI site area. Interpretation of pre-borrow excavation aerial photography shows that the faults are not geomorphically GEO.DCPP.01.21, Rev. 2 Page 51 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page _. of 185 expressed (Figure 21-40) and there is no evidence of displaced Quaternary deposits along the fault trace. 5.3.2.1 Fault Origin and Capability The faults most likely formed during a period of regional transtensional deformation during the Miocene. This most easily explains the observed normal oblique slip on the fault zone. A transition to transpressional deformation occurred during the late Miocene to Pliocene and is well expressed in the offshore Santa Maria Basin and along the Hosgri fault zone (PG&E, 1988). The minor bedrock faults at the ISFSI site were subsequently rotated during the growth of the Pismo Syncline, although the faults occur near the flat lying crest of a small parasitic anticline and, thus, have not been rotated significantly.
Given this origin, the faults formed during the Miocene contemporaneous with the transtensional formation of Miocene basins along the south-central coast of California prior to 5 million years ago. Alternatively, the minor faults may be secondary faults related to growth of the regional Pismo syncline (Figure 21-37), as concluded for the small bedrock faults at the power block (PG&E, 2000, p. 2.5-49, -50). As shown on Figure 21-31, the faults trend subparallel to the axis of the Pismo syncline, and are located near the crest of a small anticline on the southwestern limb of the syncline.
The apparent oblique displacements observed on the faults may be related to bending-moment normal faults and right shear along the axial plane of the small anticline that formed in the Pliocene to early Quaternary.
The zone of minor faulting may have used the area of diabase intrusion as an area of crustal weakness to accommodate tensional stresses along the axial plane of the anticline.
As described in the FSAR (PG&E, 2000, p. 2.5-14, -33, -34) and in the LTSP reports (PG&E, 1988, p. 2-34 to -38; PG&E, 1991, p. 2-10), growth of the Pismo syncline and related folds ceased prior to 500,000 to 1,000,000 years ago. Thus, the observed minor faults also would have ceased activity prior to 500,000 to 1,000,000 years ago.GEO.DCPP.01.21, Rev. 2 Page 52 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 5t of 185 A third alternative explanation for origin of the minor bedrock faults is that they are related to intrusion of the diabase into the Obispo Formation.
Diabase is present locally in the ISFSI study area. Forceful intrusion, or magmatic stoping of the diabase may have produced faulting in response to stresses induced by the magma intrusion in the adjacent host rock. Hydrothermal alteration is extensive in the diabase. The altered sandstone and dolomite in the ISFSI site area are spatially associated with the zone of faulting (Figures 21-4, 21-14), indicating that the faults may have acted as a conduit for hydrothermal solutions.
Assuming the hydrothermal fluids were associated with the diabase intrusion, the minor faults predate, or are contemporaneous with, intrusion of the diabase. Diabase intrusion into the Obispo Formation occurred in the middle Miocene (Hall, 1973; Hall and others, 1979), indicating that the faulting would have occurred prior to or comtemporaneous with the diabase intrusion in the middle Miocene over 10 million years ago. The faulting may have originated by transtensional regional deformation as described above, and then subsequently modified by diabase intrusion.
In addition to their probable origin related to transtensional deformation in the Miocene, or to growth of the Pismo syncline in the Pliocene to early Quaternary, or to intrusion of the diabase in the middle Miocene, several additional lines of evidence indicate that the minor faults are not capable and do not present a surface faulting hazard at the site: 1. As described in the LTSP Final Report (PG&E, 1988, p. 37 to 39, Plates 10 and 12) the Quaternary marine terrace sequence in the plant site vicinity is not deformed, providing direct stratigraphic and geomorphic evidence demonstrating the absence of capable faulting.
The minor faults observed at the ISFSI site project northwest across, but do not visibly displace the lower marine terrace platform, within a limit of resolution of +/-5 feet indicating the absence of deformation in the last 120 thousand years. Assuming that the displacement does not die out at the coast, this resolution is enough to recognize the greater than 50 of feet of vertical separation on the faults at the ISFSI site. However, no displacement of the terrace sequence is observed.GEO.DCPP.01.21, Rev. 2 Page 53 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 5 of 185 2. As described in the DCPP FSAR (PG&E, 2000, p. 2.5-35 to -50, Figures 2.5-13 to -16), similar northwest-trending minor faults were mapped in bedrock in the power block area. Detailed trenching investigations of these faults and mapping of the power block excavation provide direct stratigraphic evidence that they do not displace and, hence, are older than the late Pleistocene (120,000 years old) marine terrace deposits.
By analogy, the minor faults at the ISFSI site also would be older than late Pleistocene.
- 3. Interpretation of aerial photographs taken before the 1971 excavation of the ISFSI site area (former borrow area) and construction of the raw water reservoir (Figure 21-32), shows that there are no geomorphic features in the ISFSI site area (tonal lineaments, drainage anomalies, scarps, etc.) indicative of displacement of the minor faults prior to grading. The landscape in the ISFSI site area is interpreted to have formed in the middle to late Quaternary (about 430,000 years ago), based on the preserved remnants of marine terraces in the surrounding site area. Based on these lines of evidence, the minor faults observed in bedrock at the ISFSI site are not capable, hence, there is no potential for surface faulting at the ISFSI site. 5.3.3 Bedrock Discontinuities Extensive data on bedrock discontinuities (joints and faults) were collected from the 12 borings and 15 of the trenches within the ISFSI site area to assess their orientation, intensity, and spatial variability across the ISFSI site area. These data are presented in William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report F and summarized in Table 21-6. Rose diagrams summarizing trends of faults and joints are presented in Figure 21-41. The discontinuity data were used in both the kinematic slope stability analyses (Calculation Package GEO.DCPP.0 1.22) and the psuedostatic wedge stability analyses (Calculation Package GEO.DCPP.01.23).
Bedrock discontinuities include joints, faults, bedding, and fractures of unknown origin. These discontinuities, in particular joints, are pervasive throughout bedrock in the ISFSI GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 54 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page S ý. of 185 study area and along the transport route (Figure 21-41). Steeply dipping faults and joint sets are the dominant discontinuities, giving the rock mass a subvertical fabric. Random and poorly developed low-angle joints also occur subparallel to bedding. The fault discontinuities are described in Section 5.3.2. Joint discontinuities are described below. Joint contacts vary from tight to partially tight to slightly open; joint surfaces are slightly smooth to rough, and have thin iron oxide or manganese coatings (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report H). Joint lengths in trenches and outcrops typically range from a few feet to about 20 feet, and typical joint spacings range from about 1/2-foot to 4 feet with an observed maximum spacing of about 14 feet (as summarized on Table F-6, William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report F). The intersections of various joints, faults, and bedding divide the bedrock into blocks generally 2 to 3 feet in dimension, but up to a maximum of about 14 feet. Rock blocks formed by intersecting joints larger than those described above generally are keyed into the rock mass by intact rock bridges or asperity interlocking.
The largest expected "free" block in the rock mass is, therefore, estimated to be on the order of about 14 feet in maximum dimension.
Both the well cemented sandstone and the dolomite contain numerous joints. The jointing typically is confined to individual beds or group of beds, giving the bedrock a blocky appearance in outcrop. Joints are less well-developed and less frequent in the friable sandstone and friable dolomite.
Linear zones of discoloration in the friable sandstone may represent former joints and small faults, but these zones are partially recemented, and not as frequent or obvious as joints in the harder rock. The character ofjoints also differs between the upper, dilated zone of bedrock (generally within the upper 4 feet in the ISFSI study area, but conservatively estimated to extend to a maximum of 20 feet deep, particularly toward the edges of the old borrow cut where the amount of rock removed in 1971 is minimal) and the underlying zone of "tight" bedrock.
Joints are generally tight to open in the upper zone. In the lower zone, the joints are tight and, in places, bonded and healed. This is well demonstrated in borehole optical GEO.DCPP.01.21, Rev. 2 Page 55 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page _j of 185 televiewer logs included in William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report E that show the joints are typically tight and/or partly bonded throughout the borings. Discontinuities in recovered rock core appear to be more open than observed in the optical televiewer logs, and appear to have undergone stress-relief dilation and mechanical disruption during coring and core extraction.
In both zones, the joints are locally clay-filled, and commonly contain thin fillings of clay, calcite, dolomite, and locally, gypsum. Joints and fractures in the borings are very closely to widely spaced (less than 0.1-foot to 3-foot spacing), with local crushed areas between joints. Plots of fracture orientation and density are shown on Figure 21-41. In preparing these rose diagrams (Figure 21-41), discontinuity data from trenches (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report F) were filtered to exclude bedding and to include only joints and faults. Data for the boreholes were taken from the optical televiewer (OPTV) image logs and the discontinuities identified by NORCAL (see William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report E). Each feature identified on the logs by NORCAL was examined in detail by one or more geologists familiar with the core from the borings, to determine if the feature represents a true structural discontinuity.
In many cases, the feature appeared to be alteration, discoloration of the bedrock, or a feature with a poorly constrained or undetermined orientation.
Only those features that were interpreted as structural discontinuities (i.e., joints or faults), and for which accurate orientations could be determined, were included in the data set for the rose plots. The discontinuities used in the rose plots are tabulated in Table 21-6. Examination of Figure 21-41 shows that the discontinuity data display a spatial variability across the site, even between trenches and borings located relatively close to each other. Jointing likely developed during several phases of folding, faulting, and diabase intrusion.
As a result, joints exhibit variable orientations and cross-cutting, intersecting relationships.
In general, the discontinuities group into two broad sets: a west- to west-northwest-striking set (e.g., Trenches T-1, T-3) and a north-northwest striking set (e.g., Trenches T-5, T-15). In some trenches, fractures from both sets are GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 56 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page S8 of 185 present (e.g., Trenches T-6, T-14, T-19, while some show a much greater scatter in orientation (e.g., Trenches T-17 and T-18). In these cases, a general northwest-southeast striking orientation is apparent.
The variation in orientation of the discontinuities with strata and locality across the ISFSI site documents that the joints are limited in continuity.
The general northwest-southeast striking character of the fractures in the ISFSI site area is consistent with both the overall northwest striking regional structural grain associated with the Hosgri fault system, and with the axis of the Pismo syncline and the local fold axes in the ISFSI site area, described above (Figure 21-38). Local variations in discontinuity orientations and intensity are attributed to rheological differences between dolomite and sandstone, and their friable zones, as well as proximity to the minor faults that cut across the site area and/or former zones of diabase intrusion.
5.4 Stratigraphy
and Structure of the ISFSI Pads Foundation Figure 21-42 shows the expected bedrock conditions that will be encountered in the ISFSI pads foundation excavation at the assumed pads subgrade elevation of 302 feet. The pads will be founded primarily on dolomitic sandstone of Unit Tofb-2 and dolomite of Unit Tofb-1. Dolomitic sandstone generally underlies most of the site, while dolomite underlies the eastern end of the site. The proposed cutslopes above the site are generally underlain by dolomitic sandstone in the western and central parts of the cut and by dolomite in the upper and eastern parts of the cut. Locally, friable sandstone (Tofb-2a) and friable dolomite (TOfb-la) underlies the ISFSI pads foundation and the proposed cutslopes as shown on Figure 21-43. Because the zones are highly variable in thickness and continuity, their actual distribution likely will vary from that shown on Figure 21-42. In particular, a large body of friable dolomite underlies the southeast portion of the proposed cut slope. Other smaller occurrences of friable sandstone and dolomite are expected to be encountered in the excavation.
These friable rocks locally have "dense soil-like" properties; thus, specific analyses were performed to determine the foundation properties and slope stability of these friable rock zones GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 57 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page Y1 of 185 (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report I and Calculation packages GEO.DCPP.01.03 and 04). Small zones of altered diabase may be found in the excavations.
This rock has properties similar to the friable sandstone.
In two places beneath the ISFSI pads foundation, clay beds within dolomite and sandstone are expected to daylight and/or occur within 5 feet of the base of the foundation (Figure 21-42). Additional clay beds may be exposed in the pads foundation.
Although, available geologic data do not document the presence of clay beds that will daylight in the ISFSI cutslope, some may be encountered when the cuts are made. In addition, a zone of minor faults trends northwest-southeast across the central and eastern part of the ISFSI pads, and other minor faults may be present in the western part as well. These faults are shown on the geologic map (Figure 21-42) and on cross sections A-A', B-B"', G-G', H-H', and I-I' (Figures 21-14, 21-15, 21-20, 21-21 and 21-22). The faults have vertical separations of 10 to 30 feet and locally juxtapose different bedrock units. The CTF will be founded primarily on dolomitic sandstone (Unit Tofb-2) and friable sandstone (Unit Tofb-2a) as shown on Figures 21-22 and 21-41. 5.5 Stratigraphy and Structure of the Transport Route The transport route begins behind the power block, and ends at the Diablo Canyon ISFSI. The route will follow existing paved roads: Plant View, Shore Cliff, and Reservoir roads (Figure 21-3), except where routed north of the intersection of Shore Cliff and Reservoir roads to avoid an existing landslide at Patton Cove. The lower two-thirds of the route traverses thick surficial deposits, including marine terrace, debris-flow, and colluvial deposits of varying thicknesses.
These surficial deposits overlie two units of the Obispo Formation bedrock: unit Tofb sandstone and dolomite, and unit Tofc claystone, siltstone, and shale. The upper one-third of the route is located on engineered fill placed over GEO.DCPP.01.21, Rev. 2 Page 58 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page (,0 of 185 dolomite and sandstone bedrock (units Tofb-.I and Tofb-2 of the Obispo Formation (Figure 21-3). Locally, the road is located on cut-and-fill bench notched into bedrock.
In the geologic description below, approximate stations are assigned to assist in defining distances between locations, starting from the power block and ending at the ISFSI (Figure 21-3). Although not surveyed, this informal stationing is in standard engineering format to represent the distance, in feet, from the start of the road to the station location (for example, 21 +00 is 2,100 feet from the start of the road). The specific conditions along the route are discussed below. Station 00+00 (south side of power block) to 20+00 (near Reservoir Road): The transport route generally follows Plant View Road and Shore Cliff Road. The route starts at the power block and crosses flat, graded topography on the lower coastal marine terrace (Q2) (Figure 21-7). Behind the power block, the route is founded on sandstone (Tofb) of the Obispo Formation.
From there to near Reservoir Road, the transport route is founded on surficial deposits 10 to 40 feet thick and local engineered fill in trenches and other excavations made during construction of the power plant. The surficial deposits consist primarily of debris-flow and colluvial deposits that overlie the marine bedrock terrace platform (Figures 21-7 and 21-17). These deposits range in age from middle Pleistocene to Holocene, and consist of overconsolidated to normally consolidated clayey sand and gravelly clay. The deposits contain some carbonate cementation and paleosols, and typically are stiff to very stiff (medium dense to dense). Bedrock below the marine terrace platform consists of east-dipping sandstone (Tofb) from station 00+00 to about 07+00, and steeply dipping claystone and shale (Tofc) from about 07+00 to 20+00. Because of the thickness of the overburden, bedrock structure will have no effect on the foundation stability of the road. Station 20+00 to 34+00 (Shore Cliff Road to Reservoir Road at Hillside Road): From station 20+00 to 26+00, the transport route will be located on a new road north of the intersection of Shore Cliff Road and Reservoir Road to avoid an existing landslide at GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 59 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 4. of 185 Patton Cove (Figures 21-2, 21-6, 21-25). A 5- to 50-foot-thick prism of engineered fill will be placed to raise the elevation of the roadbed from the lower part of the marine terrace to the upper part of the marine terrace and fans as the road makes a large switchback.
The engineered fill will overlie 20- to 80-feet-thick overconsolidated to normally consolidated Pleistocene debris-flow and colluvial deposits that cover the marine terrace platform (Q2), which in turn, overlie steeply dipping claystone and shale of Unit Tofc below the marine bedrock platform.
Along Reservoir Road, station 26+00 to 34+00, the route follows the higher part of this terrace over the marine platforms Q2 and Q3 and the buried rock slope to the northeast of the platform.
The surficial deposits consist of debris-flow and colluvial deposits that are up to 80 feet thick along the base of the ridge behind parking lot 8 (Figure 21-25). Bedrock below the marine terrace is claystone and shale (Tofr) from station 26+00 to 29+50 and sandstone (Tofb) from station 29+50 to 34+00. Because of the thickness of the overburden, bedrock structure will have no effect on the foundation stability of the road. Station 34+00 (Reservoir Road at Hillside Road) to 49+00 (along Reservoir Road): The route follows Reservoir Road to the raw water reservoir area. The road traverses the west flank of the ridge on an engineered cut-and-fill bench constructed over unit Tofb dolomite and sandstone, and thin colluvium and debris-flow fan deposits.
Bedding exposed in the roadcut dips 30 to 50 degrees into the hillslope, away from the road. Engineered fill on sandstone and dolomite underlies the inboard edge of the road, and a wedge of engineered fill over colluvium generally underlies the outboard edge of the road (Figures 21-3, 21-15, 21-17, and 21-25). Bedrock joints exposed in this stretch of the route are similar to those at the ISFSI site. Joints are generally of short lateral persistence, confined to individual beds, and are tight to open. Joint-bounded blocks are typically well keyed into the slope, with the exception GEO.DCPP.0 1.21, Rev. 2 Page 60 of l18 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 0L of 185 of a 1- to 3-foot-thick outer dilated zone. No large unstable blocks or adverse structures prone to large-scale sliding were observed.
Station 49+00 (along Reservoir Road) to 53+50 (ISFSI pads): The route leaves the existing Reservoir Road and crosses the power plant overview parking area. The route will be placed on new engineered fill up to 5 feet thick that will overlie thin engineered fill (up to 4 feet thick) that was placed over sandstone and friable sandstone (TOfb-2 and Tofb-2a), the same rock that underlies the ISFSI pads and CTF site. Bedrock structures beneath this stretch of the route are inferred to be joints and small faults similar to those exposed at the ISFSI site (Figure 21-4). The faults would trend generally northwest, and dip steeply northeast and southeast, to vertical.
The primary joint sets are near-vertical.
This part of the road is on flat topography and bedrock structure will have no effect on the foundation stability of the road. The transport route is located 100 feet north of the headscarp of the active Patton Cove landslide (Figure 21-3). A cross section through the landslide is shown on Figure 21-19. The landslide headscarp is defined by a series of cracks at the intersection of Shore Cliff and Reservoir Roads (Figure 21-19). Based on detailed mapping, borings, and an inclinometer, the landslide appears to be confined within unconsolidated deposits overlying a buried bedrock sea cliff and abrasion platform.
The geometry of the bedrock surface and near vertical orientation of bedding would likely limit significant enlargement and headward encroachment of the landslide toward the transport route. Where the transport route follows Reservoir Road at the base of the bedrock hillslope north from near Hillside Road, there is no evidence for bedrock landslides.
Sandstone beds in the hillslope above the road dip obliquely into the slope at about 30 to 50 degrees (Figures 21-3, 21-14, and 21-17). These beds extend continuously across much of the hillside, providing direct evidence for the absence of bedrock slope failures.
Small faults and joints in the rock mass do not appear to adversely affect potential slope stability, and the existing roadcut and natural slopes show no evidence of slope failures.December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 61 ofl181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 4__ of 185 Kinematic analyses of the bedding and fractures along the road were performed where the road borders the bedrock slope. Two stretches of the route were analyzed:
a northern stretch from approximately station 43+00 to 49+00 (Figure 21-43), and a northwesterly stretch from approximately station 35+00 to 42+00 (Figure 21-45) (the portion of the road between 34+00 and 35+00 is friable sandstone, and kinematic analysis of this material is not applicable).
The rock mass is stable against significant wedge or rock block failures; however, the analysis indicates that rock topple failure from the cutslope into the road is possible.
Field evaluations indicate that such failures would be localized and limited to small blocks. Several colluvial or debris-flow swales are present above the transport route along Reservoir Road (Figure 21-3). These swales have been the source of past debris flows that primarily have built the large fans on the marine terraces over the past tens of thousands of years. Additional debris flows could develop within these swales during heavy rainfall events, similar to those described elsewhere in the Irish Hills following the 1997 storms (PG&E, 1997). Holocene debris-flow fan deposits extend to just below the road alignment, indicating that future debris flows could cross the road. However, large graded benches for an abandoned leach field system are present above a portion of the Reservoir Road, and concrete ditches and culverts are present in swale axes. These existing facilities will catch and divert much of the debris from future debris flows above the road. However, two debris-flow chutes are present above the road northwest of Hillside Road; this part of Reservoir Road is not protected from these potential debris flows. Based on the thickness of the colluvium in the swales (5 to 10 feet), and the slope profile, the maximum depth of debris on the road following a major rainstorm is estimated to be less than 3 feet, which easily could be removed after the event. 5.6 Comparison of Power Block and ISFSI Sites Bedrock beneath the ISFSI site was compared to bedrock beneath the power block based on (1) stratigraphic position; (2) lithology; and (3) shear wave velocity.
Based on these December 14, 2001 GEO.DCPP.01.21, Rev. 2 Page 62 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 4 of 185 three independent lines of evidence, we conclude that bedrock beneath the ISFSI site and the power block are part of the same stratigraphic sequence, and have similar bedrock properties and lithology.
- 1. Stratigraphic Position.
Cross section B-B'" illustrates the stratigraphic correlation of bedrock between the ISFSI site and the power block (Figure 21-15). As shown on the cross section, the power block and ISFSI site are located on the same continuous, stratigraphic sequence of sandstone and dolomite of Unit Tofb of the Obispo Formation.
As described previously, the power block is located approximately 400 feet lower in the stratigraphic section.
Bedrock beneath the power block is also exposed directly along strike in roadcuts along Reservoir Road (Figure 21-2). Bedrock exposed in the roadcut consists of dolomite, dolomitic siltstone and dolomitic sandstone of Unit 2. Lithology.
As described in the FSAR (PG&E, 2000, Section 2.5.1.2.5.6, p. 2.5-42, Figures 2.5-9, -10) bedrock beneath the power block consists predominantly of sandstone, with subordinate thin- to thick-bedded slightly calcareous siltstone (see boring descriptions provided on Figures 21-15 and 21-16). The rocks are described as thin-bedded to platy and massive, hard to moderately soft and "slightly punky," but firm. These lithologic descriptions are similar to, if not identical to, the rocks at the ISFSI site. The "calcareous siltstone" described in the FSAR is probably dolomite or dolomitic siltstone comparable to Unit Tofb-.. For example, based on their geologic descriptions, we interpret the "siltstone" and "sandstone" encountered in 1977 in power block boring DDH-D to be dolomite and dolomitic sandstone of Unit Tofb.i at the ISFSI site. Boring logs from the hillslope between the power block and the ISFSI site, included in the FSAR (PG&E, 2000, Figures 2.5-22 to 2.5-27; Appendix 2.5C, GEO.DCPP.0 1.21, Rev. 2 Page 63 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 45 of 185 plates A-I to A- 19), describe bedrock as tan and gray silty sandstone and tuffaceous sandstone (Figures 21-15 and 21-16). These rocks are moderately hard and moderately strong. The rock strata underlying this slope dip into the hillside and correlate with the sandstone and dolomite strata exposed on the west flank of the ridge (and west limb of the syncline) that are exposed in roadcuts along Reservoir Road south of the ISFSI site (Figures 21-1, 21-3 and 21-15) and in the deeper part of the borings at the ISFSI site. 3. Shear Wave Velocity.
Shear wave velocity data from the various investigations at the power block are summarized on Table 21-7, and Figures 21-43 and 21-44. Velocity data in Figure 21-43 are from borehole surveys at the ISFSI site (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report C) and comparative velocities at the power block in Figure 21-44 are from the FSAR. Shear-wave velocities from surface refraction and borehole geophysical surveys at the ISFSI site are within the same range as those obtained at the power block (Figure 21-45). The velocity profiles at both sites are similar to one another and are consistent with the "rock" classification for purposes of ground motion estimation (Abrahamson and Shedlock, 1997). 5.7 Parameters Recommended for Stability Analysis An analysis of slope stability is presented in Calculation packages GEO.DCPP.01.24 to GEO.DCPP.01.26.
The following physical and stratigraphic descriptions and parameters provided the basis for these analyses.
5.7.1 Pre-Existing Landslides in Diablo Canyon Near the ISFSl site Large, deep-seated landslide complexes exhibiting geomorphically well-expressed headscarps are present on the south slopes of Diablo Canyon near the ISFSI site, and south of the 230 kV and 500 kV switchyards (Figure 21-1). The complex lies entirely east of the ISFSI site, and does not encroach, undermine, or otherwise affect the ISFSI. These landslides consist of large (exceeding 100 acres), deep-seated, coalescing slides GEO.DCPP.0 1.21, Rev. 2 Page 64 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 4f of 185 that have failed within colluvium, and Tofa and Tofb bedrock on the north limb of an anticline (Section 5.3.1). The dip of the bedrock bedding in the vicinity of the slide complex is consistently to the north and downslope at moderately steep dip angles. This condition suggests that the failure planes for these slides probably are either at the contact between bedrock and overlying weathered bedrock, or within the bedrock along bedding planes, clay beds, or locally weaker diabase beds. In contrast, bedding dip directions at the ISFSI site are variable, and, where locally dipping out-of-slope, are at more-gentle dip inclinations than in the area of the old landslide complex to the east. Although the overall shape of the landslide complex is well-expressed geomorphically, the landslide deposits have been modified and subdued by erosion. Thin stream-terrace deposits and remnants of a 430,000-year-old marine terrace at elevation 290 +/-5 feet appear to have been cut into the toes of the some of the slides. These relations suggest that the landslides are old and likely formed in a wetter climate during the middle to late Pleistocene.
The older landslide masses appear to have reached a stable configuration under the present climatic and topographic setting, and are partially buttressed by the large 500 kV switchyard fill that spans the canyon. There is no geomorphic evidence of large-scale Holocene movement, and the switchyard shows evidence of no post construction slope movement.
Localized, more-recent and shallower slides have formed within the old landslide complex, and appear to involve previously-disturbed slide materials.
The slide complex is separated from the ISFSI site by a low spur ridge that is along the trend of the anticlinal axis, and which is underlain by stable bedrock that shows no evidence of past slide activity on pre-and post-borrow excavation aerial photographs.
Field mapping, subsurface exploration, and aerial photograph analyses during the ISFSI site investigations confirmed the absence of deep-seated bedrock slides at the site. Additionally, no stability problems were encountered during the 1971 borrow excavation using bulldozers and scrapers, and the slope has been stable since the 1971 excavation.
The Raw Water Reservoir and Reservoir Road below the ISFSI site show no evidence of post-construction slope movements.
GEO.DCPP.01.21, Rev. 2 Page 65 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page (0 of 185 A former small, shallow landslide in colluvium existed at the ISFSI site prior to the 1971 borrow excavation, and is shown on Figure 21-40. This slide is apparent on the pre excavation 1968 aerial photographs, and is expressed by a subtle, arcuate headscarp, hummocky landslide, and locally thicker vegetation probably reflecting high soil moisture within the slide debris (Figure 21-40). The slide was located in a slight swale in colluvial soils and possibly weathered bedrock that mantled the slope prior to excavation.
The slide mass appears to have moved northeast along the axis of the swale, and oblique to the downdip direction of bedrock bedding. This suggests that the slide was not controlled by bedrock structure.
This slide was investigated by Harding -Miller-Lawson Associates (HML, 1968), and was shown to be a shallow failure within colluvium, and possibly extending into the uppermost weathered bedrock (Cross Section A-A', Figure 21-14). This shallow slide was completely removed, along with colluvium and the surficial weathered rock zone, during the 1971 borrow excavation (Figure 21-14). 5.7.2 Clay Bed Strength The strength of the clay in the clay beds was tested in the laboratory (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report G). However, the overall strength of the clay bed during sliding also is a function of the clay bed thickness, rock asperities along the clay surface, and the amplitude of irregularities or undulations on the clay surface relative to the clay thickness.
Clay beds greater than 1/4- to 1/22-inch thick potentially have limited or locally no rock to rock contact and the clay thickness may exceed the amplitude of bedding surface undulations.
Thus, clay beds thicker than 1/4-inch should be modeled in the stability analysis using the shear strength of the clay, and are differentiated on the cross sections.
In addition, disruptions of the clay beds by joints and minor faults also will tend to resist sliding and increase the effective strength of the clay bed. The thinner beds likely exhibit shear strength greater than that of the clay due to partial rock-to-rock contacts and asperities projecting through the clay. The strength of clay beds less than <1/4-inch can be approximated by a combination of rock-to-rock and rock-to-clay strength.GEO.DCPP.01.21, Rev. 2 Page 66 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page % of 185 5.7.3 Geometry and Structure of Slide Mass Models Cross section I-I' (Figure 21-22) parallels the most likely direction of potential slope failure and illustrates the geometry of bedding in the ISFSI study area for analysis of slope stability.
The cross section shows apparent dips, and the facies variation and interfingering of beds between Units Tofb-1 and Tofb-2 beneath the slope. Lateral continuity of clay beds is approximated by the relative lengths and line weights as described above in Section 4.3. The clay beds are correlated based on stratigraphic position, projection of known bedding attitudes, and superposition of sandstone and dolomite beds (i.e., we do not allow clay beds to cross cut dolomite or sandstone beds, but allow them to cross the facies change). These clay beds, as drawn, are a reasonably conservative interpretation of their lateral continuity for the analysis of the global stability of the slope. The geometry of the folds underlying the ISFSI study area influences the potential for rock slides in the slope. As illustrated on Figures 21-3 and 21-4, the small, tightly folded, en echelon syncline at the top of the ridge above the ISFSI site transitions into a monocline above Boring 01-I. This monocline transitions into a broad syncline farther down the slope near Boring OOBA-1. The approximate locations of these transitions are indicated on cross section I-I' (Figure 21-22), but the apparent dips shown in the cross sections at the transition locations do not change because the section azimuth is subparallel to the fold axes and the direction of strata flexure is into the section. The three-dimensional change in strata geometry across these transitions will tend to disrupt and limit potential rock slides because the dip directions of the clay beds change across the transitions.
In addition, the dip of the clay beds in the upper slope above Boring OOBA-1 dip out of the slope and are parallel to the downslope direction.
Lower down on the slope (at the ISFSI pads and cutslope) the beds dip westerly.
This change in geometry reduces the potential for large rock slides on clay beds on the lower part of the slope compared to the slope above OOBA-1.GEO.DCPP.0 1.21, Rev. 2 Page 67 of l18 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 0A of 185 The continuity of some of the thicker (over about 'A-inch thick) clay beds are assumed to be up to several hundred feet. Thinner clay beds are less laterally continuous.
On cross section I-I' (Figure 21-22), clay beds are shown to terminate at set distances from exposures in boreholes.
trenches, or outcrops according to the protocol described in Section 4.3. Because of the generally limited lateral continuity of the clay beds, potential large rock slides (on the order of several tens to hundreds of feet in maximum dimensions) would likely require sliding on several clay beds, and stepping between beds on joints and in places through rock in a "staircase" profile. Stepping between basal clay failure surfaces would probably be localized where the individual clay beds are close together stratigraphically and thin and pinched-out.
Other likely locations for stair stepping failure or structural boundaries for possible rock slide margins are at the fold transitions as discussed previously and along the lateral margins of the slide and along steeply dipping discontinuities such as faults and friable or weak rock zones. Faults at the site are subparallel to the potential down slope motion and impart a strong near vertical fabric in the rock mass. It is likely that lateral margins for potential larger rock slides would develop along these faults. 5.7.4 Conceptual Rockslide Mass Models Conceptual rockslide mass models were developed for slope stability analyses of cross section I-I' (Figure 21-22) on the basis of engineering geologic evaluation of the cross section. The following assumptions were used to develop the conceptual models: 1. Basal slide surfaces generally follow low-strength clay beds encountered in ISFSI area borings and test trenches, as shown on the cross section.
- 2. Failure planes break up to the surface, or between clay beds, through jointed rock with steep shear/tension failure planes (700) that follow the dominant steep joint/fault fabric in the rock mass. 3. Locations of headscarp or tensional break-up zones are controlled or strongly influenced by locations of significant change in bedding strike and direction (structural control) or termination locations of clay beds where the beds thin and rock-to-rock contact becomes dominant.GEO.DCPP.0 1.21, Rev. 2 Page 68 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page -7D of 185 Three slide mass models were developed:
- 1. A shallow slide mass model (Figure 21-46) involving sliding rock masses along shallow beds encountered in test trench T-14A and Boring 01-I; 2. A medium-depth slide mass model (Figure 21-47) involving sliding rock masses along clay beds encountered at depths of between about 25' and 175' in borings 01-F, 0OBA-1, and 01-I and Trench T- I1D; and 3. A deep slide mass model (Figure 21-48) that involves sliding along deep clay beds behind, or below the proposed ISFSI cut slope and pad and that were encountered in borings 01-H, 01-F, OOBA-1, and 01-I at depths of between about 50 and 200 feet. Model 1 is segmented into 2 possible geometries labeled l a and lb on Figure 21-46. These two modeled slide blocks daylight at a clay bed encountered in Trench T-14A (model 1 a), or along projected dip of a clay bed encountered in boring 01-I. The failure headscarp/tension break-up zone extends upward from the inferred maximum upslope extent of the claybed in trenches T- 14A (model 1 a), or from the inferred likely extent of the uphill extent of a clay bed encountered in boring 0 1-I. Model 2 is segmented into three sub-blocks:
2a, 2b, and 2c (Figure 21-47). The three blocks daylight along a clay bed encountered in trench T-1 ID (2a and 2b), or along the dip projection of a clay bed encountered in boring OOBA-1 (2b). Model 2a breaks up at the location of a significant change in bedding strike (dip direction) that occurs near trench T-14A, and would be a major structural discontinuity for potential slide blocks. Models 2b and 2c break up from the basal failure planes in a "stair-stepping" manner between clay beds, and have a common headscarp daylight about 50 feet above the brow of the 1971 borrow cut excavation.
The geometry of the headscarp/tension break-up zone is inferred to be controlled by the uphill limit of clay beds encountered in the borings, and dominant steep joint fabric in the rock mass.GEO.DCPP.01.21, Rev. 2 Page 69 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page -11 of 185 Model 3 is segmented into three sub-blocks:
3a, 3b, and 3c. The three blocks daylight in the proposed ISFSI pad cutslope, or at the junction between the ISFSI pad and base of the cutslope (Figure 21-48). All three modeled blocks have basal slide surfaces along clay beds encountered in borings 01-F, and/or OOBA-1 and 01-I. Models 3a and 3b have headscarp/tension break-up zones at the structural change in bedding strike (dip direction) described previously for model 2a (3a and 3b), or about 75 feet above the top of the borrow cut (3c) at an inferred maximum uphill extent of clay beds encountered in borings 01-I. The toe daylight geometry reflects the propensity for failure planes to break out along bedding planes and along the projection of clay beds. The rock mass is inferred to exhibit anisotropic strength, with a lower shear strength along and parallel to bedding planes, than across bedding planes for toe shear failure. In contrast, the geometry of the headscarp-tension failure is inferred to be controlled by the dominant steep (greater than 70 degrees) joint/fault fabric in the rock mass that should control tensional failure/separation.
5.7.5 Estimate
of Potential Slide Mass Displacement Potential slide mass displacement can be constrained, in part, by past performance of the hillslope above the ISFSI site. As described below, the topographic ridge upon which the ISFSI site is located has been stable for the past 430,000 years or more. A back analysis of slope stability, therefore, provides constraints on the minimum shear strength and/or lateral continuity of the clay beds used in the analysis and a check on the conservatism of the assumptions used to analyze the stability of the proposed ISFSI site cutslopes and hillslope above the site. Geomorphic and geologic data from mapping and trenching in the ISFSI Site Area provide evidence documenting the absence of past movements of large rock masses on the slope above the ISFSI. Analysis of pre-construction air photos shows no features indicative of such landslides:
no arcuate scarps, no vegetation lineaments indicative of filled fissures, and no textural differences in the rock exposures or slopes indicative of a GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 70 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 0'1of 185 broken rock mass in the ISFSI study area (Figure 21-41) (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report A). Similarly, the many trenches and exploratory borings on the slope, the tower access road cuts, and the extensive outcrops exposed by the 1971 borrow cut did not expose tension cracks or fissure fills on the hillslope (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Reports A, B and D). Open cracks or soil-filled fissures greater than 1 to 2 feet in width should be easily recognized across the slope given the extensive rock exposure provided by the borrow cut. Therefore, we conservatively assume that any cumulative displacement in the slope greater than 3 feet would have produced features that would be evident in rock slope. The absence of this evidence places a maximum threshold of 3 feet on the amount of cumulative slope displacement that may have occurred in the geologic past. The hillslope at the ISFSI site is older than at least 430,000 years because remnants of the Q-5 (430,000 yrs) marine terrace are cut into the slope west of the ISFSI site (Figure 21-3). Preservation of the terrace documents that the slope has had minimal erosion since that time. Moreover, gradual reduction of the ridge by erosion at the ISFSI site would not destroy deep tension cracks or deep disruption of the rock mass; these features would be preserved as filled fractures and fissures even as the slope is lowered.
The topographic ridge upon which the ISFSI site is located is presumed to have experienced strong ground shaking from numerous earthquakes on the Hosgri fault zone during the past 430,000 years. PG&E (1988, p. 3-39) provides a recurrence interval of 11,350 years for an Mw 7.2 earthquake on the Hosgri fault. Therefore, approximately 35 to 40 large earthquakes have occurred during the past 430,000 years without causing ground motions large enough to produce significant (i.e., greater than 3 feet) cumulative slope displacement.
Based on the absence of cumulative slope displacement within a limit of resolution of 3 feet, the amount of possible slope displacement during the Hosgri design earthquake is a maximum of 3 feet if produced by one earthquake with very large ground motions, or, more likely about 3 to 6 inches per event if produced by multiple earthquakes with large ground motions for a cumulative displacement of up to 3 feet. Slope displacement of 3 to 6 inches, therefore, can be used as a constraint in a "back GEO.DCPP.01.21, Rev. 2 December 14, 2001 Page 71 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page -0 of 185 calculation" to assess overall rock mass strength and from that to estimate the strength of clay beds under natural slope conditions (i.e., conditions prior to the 1971 excavation of the borrow area). This back calculated strength can then be used to model potential displacements of rock slide masses in the current borrow-cut condition.
This is described in Calculation Package GEO.DCPP.01.24.
5.7.6 Rock Block Dimensions The size of potential wedge block failures in the ISFSI cutslope will be controlled, in part, by the spacing, continuity and shear strength of discontinuities in the rock mass. Both the dolomite (Unit Tofb-1) and sandstone (Unit Tofb.2) bedrock at the site are jointed and faulted. Joints and faults in friable dolomite and friable sandstone are less well developed and do not control the mechanical behavior of the soil-like rock. Rather, the rock strength appears to be controlled primarily by the cementation properties of the rock. Field data on the discontinuities (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data Report F) show that two primary joint sets are present as discussed above. The orientation of these joint sets varies somewhat across the site (Figure 21-4 1), but generally group into a west- to west-northwest-striking set and a north-northwest-to north-striking set. The joints are continuous for a few feet to about 20 feet, and commonly die out or terminate at subhorizontal bedding contacts.
Field observations from surface exposures and trenches show that the joints commonly are slightly open or dilated in the upper 4 feet, probably due the stress unloading from the 1971 borrow excavation and/or surface weathering.
Dilation of the joints reduces the shear strength of the discontinuity.
To be conservative, we assume that the zone of near-surface dilation extends to a depth of 20 feet on the ISFSI cutslope.
The Barton method is used to estimate the reduced shear strength on these discontinuities as described in Calculation Package GEO.DCPP.01.20.
Joints in the dolomite typically are spaced about '1/2-foot to 4 feet apart and divide the rock mass into blocks with average dimension of 2 to 3 feet with typical maximum dimensions of about 14 feet (William Lettis & Associates, Inc. (2001) Diablo Canyon ISFSI Data GEO.DCPP.01.21, Rev. 2 Page 72 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1,_ of 185 Report F, Table F-6). We anticipate that the maximum block size will be less than 14 feet in dimension, and conservatively assume a maximum block size of 20 feet in the wedge block stability analysis (Calculation Package GEO.DCPP.01.23).
This larger dimension conservatively allows for multiple-block wedges to form in the cutslope.
6.0 RESULTS
The results of the stratigraphic and structural analysis are presented on the geologic maps (Figures 21-1, 21-3, 21-4), a stratigraphic column (Figure 21-5), twelve cross sections (Figures 21-13 to 21-24), and a map of geologic conditions at the ISFSI and CTF foundation grade (Figure 21-42). This information was used to interpret the depositional and structural history of bedrock in the ISFSI study area and along the transport route (Figure 21-7). The results of this calculation package also provide important information used to evaluate the stability of cutslopes at the ISFSI site, the hillslope above the ISFSI site, and slopes above the transport route (Calculation packages GEO.DCPP.01.08, .22, .23, .24 and .28), and to characterize the foundation conditions at the ISFSI pads and cutslope (Calculation packages GEO.DCPP.01.03, .04 and .06). 7.0 SOFTWARE The software program "DIPS" (Rocscience, 1999) was used to compile and analyze the structural continuity data presented on Figures 21-38 and 21-40. The DIPS program is documented and verified in Calculation package GEO.DCPP.01.22 "Kinematic stability analyses for cutslope at DCPP ISFSI site". No other software programs were used in this calculation package.
... ., D. ."7 1 December 14, 200 51.GI IJ v v GEOL.IX;-PRO.
12., 1, R~ev. 2 Calculation 52.27.100.731, Rev. 0, Attachment A, Page IS of 185
8.0 CONCLUSION
S This calculation package provides an analysis of the stratigraphic and structural geology of the plant site area (Figure 21-1), transport route (Figure 21-3), and the ISFSI study area (Figure 21-4). Interpreted cross sections and structural maps developed as a result of these analyses are used to characterize the ISFSI pads foundation properties, to evaluate slope stability of the existing hillside and proposed cutslopes above the ISFSI pads and along the transport route, and to understand subsurface bedrock conditions for use in evaluating ground motion site response.
Figure 21-42 shows the bedrock conditions expected at the ISFSI pads and CTF foundation grade levels. The ISFSI pads will be founded primarily on dolomitic sandstone of Unit Tofb_2 with dolomite of Unit Tofb-I in the eastermmost part of the site. Locally, friable sandstone and friable dolomite will be encountered beneath the ISFSI pads foundation.
The proposed cutslopes above the site will be underlain by sandstone and dolomite, and by a large body of friable dolomite in the eastern part of the cutslope.
At least two clay beds will daylight within the ISFSI pads foundation.
Other clay beds may be encountered in the foundation excavation and in the cutslopes.
The CTF will be founded on dolomitic sandstone of Unit Tofb-2 and friable sandstone of Unit Tofb-2a.
Bedrock beneath the ISFSL and CTF sites is part of the same stratigraphic sequence that underlies the DCPP power block. Cross section B-B'" (Figure 21-15) illustrates the location of the ISFSI site and power block relative to the stratigraphic sequence.
Bedrock encountered in boreholes at the ISFSI site and during site investigations for the power block (PG&E, 2000, Section 2.5.1.2.5.6) have similar lithology and shear wave velocities (Figure 21-45). The bedrock characteristics and velocity profiles at both sites are consistent with the "rock" classification of Abrahamson and Shedlock (1997). Stratigraphic and structural information developed in this calculation package provide basic geologic information for the analysis of slope stability for the ISFSI pads cutslopes, GEO.DCPP.01.2 I1, Rev. 2 Page 74 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page __of 185 the hillslope above the IFSI site, and the slope above the transport route. In particular, cross section I-I' (Figure 21-22) should be used as the basis for analyzing global slope failure at the site assuming the geometry of bedding and lateral continuity of clay beds as shown on the cross section. The structural transitions between the monocline and the small synclinal folds are considered to be structural discontinuity boundaries that would limit the size of potential large scale rock slides in the slope. The analyses and results presented in this calculation package are based on geologic interpretation of available surface and subsurface data using generally accepted techniques and methods. Geologic judgement, experience and knowledge of the site conditions by the geologists working on the project were used to integrate the available geologic, geophysical and geotechnical data to formulate the interpretations and conclusions presented in this calculation package. Actual subsurface conditions may vary from that shown on the geologic maps and cross sections, but those variations are not expected to significantly change or alter the primary conclusions reached in this analysis.
9.0 REFERENCES
Abrahamson, N. A. and Shedlock, K., 1997, Overview [of Special Issue of SRL on Attenuation Relations], Seismological Research Letters, v. 68, no. 1, p. 9-23. Compton, R. R., 1985, Geology in the Field. New York: John Wiley & Sons, 398 p. Deere and Miller, 1963, Engineering classification and index properties of intact rock: Technical Report No. AFWL-TR-65-116.
Air Force Weapons Laboratory, Kirkland Air Force Base, New Mexico, in Hoek, E., 2000, Rock Engineering Course Notes, on-line document, Chapter 3, pgs. 42 -44. Hall, C.A.,1973, Geologic map of the Morro Bay south and Port San Luis Quadrangles, San Luis Obispo County, California, U.S. Geological Survey Field Studies Map MF511.GEO.DCPP.01.21, Rev. 2 December 14. 2001 Page 75 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1i of 185 Hall, C. A., Jr., Ernst, W. G., Prior, S. W., and Siese, J. W., 1979, Geologic map of the San Luis Obispo-San Simeon region: U.S. Geological Survey Miscellaneous Investigation 1-1097. Harding-Miller-Lawson Associates, 1968, Report, soil investigation, intake and discharge lines, borrow area, and switchyards for Unit 1, Diablo Canyon site, San Luis Obispo County, California, consultant's report, 14 p. Harding-Lawson Associates, 1970, Landslide investigation, Diablo Canyon site, San Luis Obispo County, California, consultant's report. John A. Blume & Associates, 1968, Recommended Earthquake Design Criteria for Nuclear Power Plant -Unit No. 2, Diablo Canyon Site: Diablo Canyon Unit 2 PSAR, Docket No. 50-323, June 24, 1968. PG&E, 1988, Final Report of the Diablo Canyon Long Term Seismic Program (LTSP), 8 chapters.
PG&E, 1989, Response to NRC Question 19, dated December 13, 1988, Docket Nos. 50-275 and 50-323. PG&E, 1991, Addendum to the 1988 Final Report of the Diablo Canyon Long Term Seismic Program (LTSP), 8 chapters.
PG&E, 1997, Assessment of Slope Stability near the Diablo Canyon Power Plant, Response to NRC Request of January 31, 1997, 86 p. PG&E, 2000, Units 1 and 2 Diablo Canyon Power Plant, Final Safety Analysis Report Update, Revision 13. Reading, H.G., 1981, Sedimentary Environments and Facies: Elsevier, New York, pp. 392-386.
Rocscience, 1999, DIPS: plotting analysis and presentation of structural data using spherical projection techniques, version 5.041, Toronto Rowland, S. M., 1986, Structural analysis and synthesis:
a laboratory course in structural geology. Blackwell Scientific Publications, Boston, 208p. Suppe, J., 1985, Principals of structural geology, Prentice Hall, New Jersey, 537 p. William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report B, Rev. 1, Borings in ISFSI Site Area.GEO.DCPP.0 1.21, Rev. 2 December 14, 2001 Page 76 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page l1 of 185 William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report C, Rev. 1, 1998 Geophysical Investigations at the ISFSI Site Area, (by Agbabian Associates and GeoVision).
William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report D, Rev. 1, Trenches in the ISFSI Site Area. William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report E, Rev. 1, Borehole Geophysical Data (by NORCAL Geophysical Consultants, Inc.). William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report F, Rev. 1, Field Discontinuity Measurements.
William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report G, Rev. 1, Soil Laboratory Test Data -Cooper Testing Laboratory.
William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report H, Rev. I, Rock Strength Data and GSI Sheets. William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report I, Rev. 1, Rock Engineering Laboratory Testing -GeoTest Unlimited.
William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report J, Rev. 1, Petrographic Analysis (Spectrum Petrographics, Inc.). William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report K, Rev. 1, Petrographic and X-Ray Diffraction Analyses of Clay Beds (by Schwein/Christensen Laboratories, Inc.). William Lettis & Associates, Inc., 2001, Diablo Canyon ISFSI Data Report L, Rev. 1, Geologic Mapping in the Plant Site and ISFSI Site Areas. William Lettis & Associates, Inc., Work Plan, 2000, Additional Geologic Mapping, Exploratory Drilling, and Completion of Kinematic Analyses for the Diablo Canyon Power Plant, Independent Spent Fuel Storage Installation Site, Rev. 2, November 28, 2000. William Lettis & Associates, Inc., Work Plan 2001, Additional Exploratory Drilling and Geologic Mapping for the DCPP ISFSI Site, Rev. 1, September 29, 2001. Geosciences Calculation packages GEO.DCPP.01.01 Development of Young's Modulus and Poisson's ratios for DCPP ISFSI based on field data GEO.DCPP.01.21, Rev. 2 Page 77 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page -1 of 185 GEO.DCPP.01.02 GEO.DCPP.01.03 GEO.DCPP.01.04 GEO.DCPP.01.06 GEO.DCPP.01.07 GEO.DCPP.01.08 GEO.DCPP.01.11 GEO.DCPP.01.15 GEO.DCPP.01.19 GEO.DCPP.01.20 GEO.DCPP.01.22 GEO.DCPP.01.23 GEO.DCPP.01.24 GEO.DCPP.01.25 GEO.DCPP.01.26 GEO.DCPP.01.28 GEO.DCPP.01.29 Determination of probabilistically reduced peak bedrock accelerations for DCPP ISFSI transporter stability analyses Development of allowable bearing capacity for DCPP ISFSI pad and CTF stability analyses Methodology for determining sliding resistance along base of DCPP ISFSI pad Development of lateral bearing capacity for DCPP CTF stability analyses Development of coefficient of subgrade reaction for DCPP ISFSI pad stability checks Determination of rock anchor design parameters for DCPP ISFSI cutslope and CTF guy lines Development of DCPP ISFSI horizontal and vertical spectra Development of Young's Modulus and Poisson's ratio values for DCPP ISFSI based on laboratory data Development of Strength Envelopes for jointed rock mass at DCPP ISFSI using Hoek-Brown equation Development of strength envelopes for shallow discontinuities at DCPP ISFSI using Barton equations Kinematic stability analysis for cutslopes at DCPP ISFSI site Pseudostatic wedge analysis of DCPP ISFSI cutslope (SWEDGE analysis)
Stability and yield acceleration analysis of cross section I-I' Determination of seismic coefficient time histories for potential sliding masses along cutslope behind ISFSI pad Determination of earthquake-induced displacements of potential sliding masses on DCPP ISFSI slope Stability and yield acceleration analysis of potential sliding masses along DCPP ISFSI transport route Determination of seismic coefficient time histories for potential sliding masses on DCPP ISFSI transport route GEO.DCPP.01.21, Rev. 2 Page 78 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page W of 185 Table 21-1 Interpretation of Bedding in Boreholes, ISFSI Study Area Boring OOBA-1 Original Description from WLA Descriptions from Log of Rock Boring including NORCAL Televiewer Image dip angle t 1) including dip azimuth and dip Interpreted (DCPP ISFSI angle(2) Bedding Data Report B) (DCPP ISFSI Data Report E) Review of Core(3) Attitude(4) Depth 1 Description Depth Description (strike, dip) (feet) I (feet) 23.0- Four joints with thin 23.1 Moderately steep joint Not checked N25 0 E 23.2 clay coatings (altered and thin clay (?) bed, 9 0 NW zone) 2950, 90 (fair) 34.0- Dolomite to dolomitic 34.0- Massive rock with Clear bedding laminations, N45°W, 38.0 sandstone, laminated 38.0 laminations, slightly dips 110, azimuth 224 14 0 SW bedding, dips 00 etched surface at 36.9, measured from dip direction 2250, 14' (good) in televiewer 39.0 Dolomite to dolomitic 38.1 Slightly etched surface Excellent bedding, 10' N50°W, sandstone, laminated in massive rock with I 0°SW bedding, laminations 00 dip 2200, 100 (good) 45.0- Dolomitic sandstone, 45.2 Color lamination in Well defined parting surface N85 0 W, 48.5 laminated bedding, massive rock, at 48.8 feet along bedding, 100S dips 0-7' 1850, 150 (fair) with fossils on bedding up to 0.2 inches, dips 10' 55.6- Clay seam (0.7 foot) 54.9- Clay bed with sharp, Core not available; removed N82 0 W, 56.3 with planar rock 56.2 tight rock contacts, for testing 11-16 0 S contacts, liedding etched, top dips 50, 1880, 200 (N) bottom dips 50 Remeasured dips: (good) top 110, bottom 160 (good) 59.0- Dolomitic sandstone, 57.0- Hard rock with steep to Good bedding at 59.7 feet, N42 0 W, 61.0 bedding (?) at 59.7 60.5 moderately steep dips 16-18', azimuth of 2280 16°SW dips 100 fractures, vague measured from fracture laminations orientation (good) 79.5 Stiff, silty clay seam 79.2 Possible thin clay along 2-4 mm clay bed dips 160 N61°E, (1/8-inch) on joint, bedding orjoint, etched I 1-16 0 NW dips 100 below 3310, 12 0 (N) Checked dip: 110 (fair) 105.4 Clay seam (1/4 inch) 105.0- Clay seam, etched, No clay found in core; NI3-W, along fracture, 105.3 sharp irregular top, appears that clay washed out 12*SW dips 150 smooth bottom contact, during drilling 2570, 120 (N) (good) 106.5 Silty clay (1/8-1/4 106.4 Tight bedding with Not checked N20°W, inch), joint, discoloration 18 0 SW (?) dips 100 248-2530 (N),17-180 (N) (fair) 140.0- Sandstone, changes to 140.4 Thin clay (?) bed, partly Thin clay bed between runs, NIO 0 W, 141.0 laminations
@ 140.9 etched, 2600, 40 (fair) dips -9O; not accurate 4 0 SW GEO.DCPP.01.21 Rev. 2 Page 79 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page qj of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring OOBA-2 Original Description from WLA Descriptions from Log of Rock Boring including NORCAL Televiewer Image dip angle0') including dip azimuth and dip Interpreted (DCPP ISFSI Data Report B) angle 2) Review of Core(3) Bedding (DCPP ISFSI Data Report E) Attitude(4) Depth Description Depth Description (strike, dip) (feet) (feet) 00.0- No bedding T No bedding No bedding recognized 55.0 recognizedj recognized Boring 01 CTF-A Original Description from WLA Descriptions from Log of Rock Boring including NORCAL Televiewer Image dip angle0') including dip azimuth and dip Interpreted (DCPP ISFSI Data Report B) angle'2) Review of Core(3) Bedding (DCPP ISFSI Data Report E) Attitude(4) Depth Description Depth Description (strike, dip) (feet) (feet) 8.0- Coarse to fine grained 8.8-8.9 Two subhorizontal, Core not available; N53 0 W, 9.4 sandstone slightly open to etched removed for testing 6°SW (?) partings on bedding (?), lower parting 2170, 60 (N) (poor to fair) 12.4 Fine grained to coarse 12.4- Two subhorizontal, Broken sandstone N88°E, grained sandstone 12.6 slightly open to etched 7°S (?) partings on bedding (?), upper parting 178', 70 (N) (poor to fair) 32.4- Soft clayey sand, 32.7- Soft clayey (?) zone, Core not available;
?? 32.6 bedding (?), dips 300? 33.5 etched, irregular removed for testing contacts, attitude not evident on image. I GEO.DCPP.01.21 Rev. 2 Page 80 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page I L of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01 -A WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angle t 1) 2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4)
Depth Description Depth [ Description (strike, dip) (feet) (feet) ! 37.7- Two clay (1 mm) 36.7 Low to moderate Not checked N40°W, 37.8 coatings on joints, dips dipping joint or bedding 20 0 SW 20_300 (?), etched 224, 27, (N) remeasured orientation 2300, 20' (fair to good)_ 42. I Sandstone, no 41.0- Textural change, Not checked N 19 0 W, recovery 41.1 etched, bedding (?) with 23 0 W clay (?) 251P, 23' (good) 54.9 Silty clay with sand 54.1- Low-angle bedding Could not confirm N69°E, and gravel (1 inch), 54.3 with textural change, orientation, but modified 7°NE bedding (?) dips 200 etched and eroded, 1/2- pick appears reasonable to 1-inch clay bed (?) 021-, 7 0 (N) 55.8 Faults with thin clay 55.3 Bedding (?), etched, Not checked N44W, coatings, slickensides, with thin clay (?) bed 23 0 SW dips 8-20' 226, 270, (N) remeasured dip 200, 270 (fair) 58.8 1 cm clay layer, dips 58.5 Subhorizontal clay Not checked NI 1W, 200 layer, eroded and 22 0 W etched, irregular, 1/4 1/2 inch thick, bottom 2590, 220 (N) (fair) 63.0- Fine grained dolomitic 64.7 Slightly etched bedding Bedding surface in core N 14°W, 66.0 sandstone
(?) in massive rock with dips at 110 110 W broad color laminations 2560, 120 (N) (good)GEO.DCPP.01.21 Rev. 2 December 14, 2001 Page 81 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page d, of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01-B WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angle°') angle(2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4)
Depth Description Depth Description (strike, dip) (feet) (feet 25.0- Medium grained 26.1 Tight bedding plane Not checked N55-E, 27.0 sandstone, joint at 26.2 (?), slightly etched, in 9 0 NW dips 00 zone of vague color laminations 3250, 90 (N) (fair) 32.5 Medium grained 32.0- Possible bedding, Two good laminations N 10°W, dolomitic sandstone 32.2 etched to partly open, within coarser rock, I O 0 SW 2580, 22, (N) azimuth, -N50°W, dip remeasured 10-150 260°, 50 (N) (fair) 37.7 Gradational contact 37.0 Sharp textural change Not checked N6E, between medium to from hard fractured 7 0 W coarse grained rock to massive etched sandstone, dip not rock, bedding, indicated 1 2760, 70 (N) (good) I Boring 01-C WLA Descriptions from Original Description from NORCAL Televiewer Image Interpreted Log of Rock Boring including including dip azimuth and dip Bedding dip angle0' angle(2) Review of Core(3) Attitude(4) (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) (strike, dip) Depth Description Depth Description (feet) (feet) 13.0- Sandstone, medium to 13.8 Bedding, etched, Not checked N49°W, 14.0 fine grained 2210, 13' (N) (fair) 13 0 SW 16.3 Clay film on joint, 15.9 (?) Low-angle bedding, Surface in core not N73°W, dips 15' etched, with clay (?) confirmed as bedding, 150S (-1/8 inch) dips 16-17' 197', 15' (N) (good) 23.8 Joint, dips 50 23.7- Bedding, etched, with Core not available; N66 0 W, 23.8 clay (?) (-1/4 inch) removed for testing 150 SW 2280, 100 (N) Remeasured orientation:
-204', 150 (fair to good)GEO.DCPP.01.21 Rev. 2 Page 82 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page SA of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01 -D WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angle") angle(2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4)
Depth Description Depth Description (strike, dip) (feet) (feet) 36.0- Fine to medium 36.9- Two subhorizontal Not checked N20 0 E 39.0 grained sandstone with 37.1 fractures, open and in 5 0 NW crushed zones, joints part tight, bedding (?), dip 00 and steeply bottom 2900, 50 (N) (fair) 55.0- Crushed zone with 53.4- Eroded and etched zone Sandstone layers and N33°W, 55.5 clay, joint at 55.2 54.9 (clayey?), rough contact with dolomite I l 0 NE bedding (?) at base dip 100 1 1 0570, 110 (N) (good) Boring 01-E WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted
.dip angleM') angle(2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4) Depth Description Depth Description (strike, dip) (feet) (feet) 46.5- Sandy dolomite to 46.5- Unfractured, hard rock, Irregular bedding NS, 48.0 dolomitic sandstone; 48.0 weak laminations laminations at 47.5 feet, 8 0 E horizontal to 090', dip 80 measured subhorizontal laminar from fracture orientation banding on televiewer (good) 48.0 (same as above) 48.0 Top of thin (0.1 feet) Core not available; N60°E, dark bed (clay?), removed for testing I O 0 NW(?) 3320, 17 (N) remeasured
-330*, 100 (fair) 48.8 (same as above) 48.8 Bottom of moderately Core not available; EW, dark bed (0.7 feet), removed for testing. But 3 0 N parallels the base of the @ 50.5 feet bedding dark bed at 48.1 feet laminations in core dip 3600, 40 (fair to good) 30 _ _GEO.DCPP.01.21 Rev. 2 December 14, 2001 Page 83 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1$ of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01-F WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angle(') angle(2 Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4) Depth Description Depth Description (strike, dip) (feet) (feet) 6.8 Clay film (<1/16 6.6 Partly open joint with Not checked N70°W, inch), joint, dips 200 thin clay (?), shallow 9 0 SW bedding (?) 2000, 90 (fair) 94.3- Clayey, silty crushed 93.2 Subhorizontal joint Thick clay (1/4- 1/2 EW, 94.4 rock with clay bed along bedding with 1/4 inch) over 1/4-inch-140S (0.5-1 cm thick (1-V 2 inch clay (?), etched thick, white, moderately in)) 1800, 150 (N) (good) soft calcite vein at 94.8 dips 0-10' feet, dips 140 117.0 Clay layer (1 cm), 116.4 Subhorizontal bedding, Core not available; N70°W, bedding (?) dips 8-12° etched, possible thin removed for testing 6-12 0 SW clay (-1/8 inch) 2000, 50 (N) Remeasured dip: 60 (good) Boring 01-G WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angle() angle(2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4)
Depth Description Depth Description (strike, dip) (feet) 1(feet) 18.7 Clay seam (1/2-3/4 18.5 Subhorizontal, tight Core not available; N22°W, inch) above broken bedding laminations removed for testing 13 0 SW rock zone on bedding possible thin (<1/4 (?), top horizontal, inch) clay (?), bottom dips 0-5o 245-2510, 11 (N) average 248', 130 (N) (fair to good) 25.4 Joint with clay 25.0 subhorizontal bedding, Not checked N78°W, coatings (<0.5 inch), tight with thin clay (?) 150S dips 0-- 15* (<1/8 inch), 192, 15 (N) (fair) 29.1 Joint with very thin 28.8 Bedding (?), partly Not checked N60°W, film, dips 0' broken out in zone of 12 0 SW massive rock -210, 120 (fair) 56.3 Clayey fracture zone 55.8- Steep joints and Red brown laminations Unknown parallel to laminations, 57.5 broken rock, localized dip 5-8' strike, dips laminations dip 0-10' clay (up to -1/2 inch) 5-80 on joint GEO.DCPP.01.21 Rev. 2 Page 84 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 81, of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01-H WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angle() 2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4)
Depth Description Depth Description (strike, dip) (feet) (feet) 39.4 Two very thin clay 39.4- Subhorizontal bedding, Three thin clay beds, N30 0 W, layers between 41.2 slightly etched, with dip 15' 15 0 SW fracture blocks dip 300 thin clay (?), 253-284, 2 (N) Remeasured orientation on clay bed at 41.2 feet: -240-, 50 (fair) 58.7 Fine to medium 58.7 Thin bed Not evident in core. N59 0 W, grained dolomitic 211, 130 (N) (fair) 13 0 SW sandstone, @ 58.9 feet clay layer, 0.01 feet thick on 'joint' dips 100 82.3 Clay seam (0.05 feet 81.4 Subhorizontal bedding Not checked N45 0 W, thick) on joint, dips 00 laminations, tight, no 12 0 SW clay evident, 225, 120 (N) (fair) 89.6 Sandstone 88.8 Bedding, textural 2 mm clay bed twisted N67°W, change 203, 1.10 (N) by drilling I 1 0 SW (fair to good) 94.5 Dark gray clay layer 93.6 Subhorizontal bedding, Highly fractured, clay N38-W, (0.2 inch), dips 10-30' eroded with clay (?) layer not found 21 0 SW 202, 2- (N) Remeasured:
2320, 21' (good)GEO.DCPP.01.21 Rev. 2 December 14, 2001 Page 85 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page ¶1 of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01-I WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angleU) angle(2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4) Depth Description Depth Description (strike, dip) (feet) (feet) 33.9 Clay film (1/16 inch) 34.9 Subhorizontal lamination, Not checked N39°E, on bedding, joint (?), tight to partly eroded 6 0 NW dips 100 bedding, 3090, 60 (N) (good) 43.1 Clay on joint (1/4 43.4- Thin clay, eroded and Not checked N55°E, inch), dips 200 43.6 etched along bedding(?), 18 0 NW 3250, 18° (N) (good) 45.6 Clay bed (2 cm), dips 46.2 Well imaged thin clay, Not checked N54 0 E,10-150 etched, bedding parallel, 14 0 NW 3240, 14' (N) (good)_ 48.1 Clay seam (1 cm) on 48.8 Subhorizontal joint/clay Not checked N50°E, joint associated with seam (1/4-1/2 inch), 13 0 NW CaCO 3 vein, dips 10- etched, 200 320', 130 (N) (good) 57.2 Sandy crushed zone 57.6- Subhorizontal, planar Crushed zone, remnant N25 0 E, 57.9 opening along eroded soft bedding dips 15' 8-15°NW rock zone (1/2 to 1 inch); thin clay (?) along base, bedding, near bottom of clay bed 295', 8 0 (N) (fair to good) 86.0- Dolomitic sandstone, 86.8- Clear laminations in hard Bedding laminations N 15-E, 87.0 laminations dip 12-200 88.5 rock, near vertical fracture dip 150, azimuth of 15 0 W 285' measured using fracture orientation (good) 89.5- Dolomitic sandstone 89.2- Clear lithologic banding Bedding laminations N15°E, 89.8 90.7 in unjointed, hard rock dip 13 14 0 W 276, 18°(N) 285, 200 (N) (fair)GEO.DCPP.01.21 Rev. 2 Page 86 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 'K of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01-I (continued)
WLA Descriptions from Original Description from NORCAL Televiewer Image Log of Rock Boring including including dip azimuth and dip Interpreted dip angle(G) angle 2) Review of Core(3) Bedding (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Attitude(4)
Depth Description Depth Description (strike, dip) (feet) (feet) 102.0- Very fine grained to 102.0- Hard rock with Laminations N45 0 E, 105.0 fine grained dolomitic 105.0 laminations and two dip 130 (fair to good) 13 0 NW sandstone, well near vertical fractures, defined laminations at 103.7 3150, 110 106.6 Clayey/silty/sand seam 106.4 Subhorizontal clayey Clay bed not found in N I9°W, (2 cm), bedding, seam (I to 2 inches core, but bedding 12-14°W dips 10-12' thick), eroded and laminations one foot etched along bedding above and below dip 12 top 266', 16 0 (N) 140 bottom 251 0, 17 0 (N) (good) 123.8- Clayey sandstone bed 124.1 Irregular bedding Not checked N46 0 W, 124.0 above coarse, 0.1 -foot- contact between broken 16 0 NE thick sandstone bed, rock and soft, granular dips10-200 rock, eroded, 0440, 160 (N) (fair) 130.3 Stiff clay seam (1/2-1 130.8 Bedding with clay (?) Not checked NI2 0 E, cm) along bedding, slightly etched, 3E dips 100 1020, 30 (N) (fair) 131.0 Joint with clay, dips 131.6 Bedding with thin clay, Not checked N81 0 E, 200 subhorizontal, 8 0 S 1710, 8'(N) (good) 156.1 Shaley seam (1/4 inch) 156.5- Softer rock zone, Bottom of clay bed N65 0 E, with slickensides 156.8 eroded and etched, washed out during 12-18ONW along bedding contact, subhorizontal, possible drilling.
dips 15-18 clay at base of zone, bedding, 3350, 12' (N) (good) 171.0- Crushed zone with 170.0- Clear laminations and Bedding dips 120, at N20 0 E, 171.2 silty clay in joint (1/8 173.0 steep, partly open joints 170.5 feet azimuth of 12 0 NW inch), possible slough with clay (?), --294" measured using at bottom, dips 100 2850, 120 (N) (good) fracture orientation 172.5- Dolomitic sandstone, 171.0- Clear lithologic Bedding on two beds, N 15-E, 173.1 laminations dip 10-12' 173.5 banding and near dips 110, 15' (azimuth I loW vertical joint measured using fracture 272-2850 (N), orientation confirms 11-1 2°(N) strike in televiewer)
GEO.DCPP.01.21 Rev. 2 Page 87 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page %IN_ of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01-I (continued)
Original Description from Log of Rock Boring including dip angle0') (DCPP ISFSI Data Report B)Depth Description WLA Descriptions from NORCAL Televiewer Image including dip azimuth and dip angle(2) (DCPP ISFSI Data Report E)Depth (feet)Description Review of Core(3)GEO.DCPP.01.21 Rev. 2 Interpreted Bedding Attitude(4, (strike, dip)173.8- Dolomitic sandstone, 173.5- Clear fine lithologic Core has good N30°E, 175.0 thick laminations 176.6 banding, typical: laminations, bedding 10-13 0 NW dip -10' 2960, 15- (N) dips 10-13', 2850, 14 0 (N) 2920, 130 (N) 3090, 10°(N) 316, o 13o (N) average 3000, 130 good) 185.0- Two clay beds (2 cm; 185.7- Subhorizontal clay bed Dip on bottom of clay N47 0 E, 185.3 1 cm) with crushed 186.1 (0.4 feet thick), etched, bed is12-14o 12-14"NW zone between, dips 10- Bottom 200 3170, 18' (N) (good) 188.5 Clay film (1/16 inch) 188.0- Solid rock with color Not checked N3 0 W, on joint, dips 100 189.0 laminations, slightly 7 0 E etched, 2670, 70 (N) (good). 198.4- Dolomitic sandstone, 196.0- Massive rock with color Well defined N20°E, 199.8 laminations 201.0 laminations, slight laminations, 12 0 NW dip 5-12' etching at 197.1 dip 140, 110 Following are typical: 2950, 90 (N) 2910, 10°(N) 2890, 90 (N) average 2900, 90 (good) 215.8- Crushed zone with 215.9- Irregular, subhorizontal Not checked N4 0 E, 216.0 clay seam, 216.4 bedding with brown 29 0 W slickensides clay (1 inch), eroded and etched, bottom contact 2740, 29 (N) (good) 236.3 Stiff clay seam (1 cm) 236.8 Subhorizontal clay Bedding in core dips 12- NI7'W, on bedding, dips 15' (1/4-1/2 inch) along 130, azimuth measured 13 0 SW laminations, etched using fracture orientation and squeezing into confirms strike from hole televiewer 2530, 130 (N) (good)December 14, 2001 Page 88 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page .0 L of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Boring 01-I (continued)
Original Description from Log of Rock Boring including dip angle(') (DCPP ISFSI Data Report B)Depth Description WLA Descriptions from NORCAL Televiewer Image including dip azimuth and dip angle(2) (DCPP ISFSI Data Report E)Depth (feet)Description
________________________________________________________________
T Review of Core(3)252.4- Bed of medium to 252.9- Washed out zone, Undulating laminations, N45 0 W, 252.7 coarse grained 253.2 friable sand (clay ?), dip 10-13' 10-13 0 W sandstone, contact bottom bedding dips 10-11', bedding 1840, 40 (N) laminations dip 100 remeasured 2250, 70 (fair to good) 259.2- Very fine grained 259.1- Lithologic banding; Irregular laminations at N12°W, 259.6 dolomitic sandstone, 259.5 Following are typical: 259.0 dip -180, parting 12 0 W subhorizontal bedding 2540, 120 (N) surfaces at 259.9 feet dip laminations dip -10' 2620, 130 (N) 160 (good) 283.6- Very fine-grained 286.3- Laminations Good laminations dip N33 0 E, 286.3 sandstone, 286.7 299-315-,13-170 (N) 110; azimuth of 303' 11°NW laminations, bedding (fair) measured using fracture dip 00 orientation 289.9- Clay seam/bed (1/2-1 290.4 Subhorizontal clay bed Not checked N62E, 290.0 cm), dips 10-15' (1/4-1/2 inch) along 18 0 NW laminations, etched to partly open, irregular 3220, 180 (N) (fair) 316.0- Very fine grained 316.0- Laminations Laminations dip 10-13Y, N9 0 E, 316.6 sandstone, laminations 317.0 2730, 15 (N) with few irregular 12 0 W 2790, 120 (N) (good) laminations up to 180 December 14, 2001 GEO.DCPP.01.21 Rev. 2 Interpreted Bedding Attitude (4) (strike, dip)Page 89 of 181 I Calculation 52.27.100.731, Rev. 0, Attachment A, Page q of 185 Table 21-1. Interpretation of Bedding in Boreholes, ISFSI Study Area (continued)
Notes: (1) Description and depth (in feet) of feature described on log of rock boring by field geologist.
Dip angle measured from core with protractor by field geologist.
In some cases, no field measurement was taken. Note that some features such as joints have been reinterpreted as bedding from subsequent review of core and/or interpretation of televiewer image. (2) WLA description and depth (in feet) of feature observed in NORCAL Televiewer image of boring. Dip azimuth and dip angle measurements taken from NORCAL interpretation are designated with (N). NORCAL measurements are described in DCPP ISFSI SAR Section 2.6 Topical Report DCPP ISFSI Data Report E. All other dip azimuth and dip angle measurements were obtained by WLA from televiewer image and represent either bedding not picked by NORCAL or remeasured by WLA where noted. WLA physically measured dip and dip azimuth on televiewer image hard copy in the following manner: Bedding occurs as sinusoidal form on unfolded borehole image. The dip direction is taken as the lowest point on the sinusoidal curve. The dip angle is calculated using the parameters of (1) measured amplitude of the sinusoidal curve (h) and (2) the boring diameter (d) in the equation tan (dip angle) = h/d. A good, fair, or poor rating was assigned to the bedding attitude to convey the quality of measurement and confidence that the feature in the televiewer image represents bedding.
(3) Comments from reinspection of core samples including dip measurements where noted. Dip azimuths are measured and noted where core could be oriented using attitudes of prominent fractures or joints obtained from televiewer images. "Not checked" refers to bedding attitudes that were interpreted from televiewer images following the last reinspection of the core. (4) Strike and dip of interpreted bedding. The interpreted bedding represents the best information obtained from field logs, NORCAL televiewer images, and reinspection of core samples. For example, the interpreted strike of bedding may be obtained from the televiewer images, but the corresponding dip may be taken from original field measurements of core samples, televiewer images, or measurements of core during reinspection, whichever is considered highest quality/confidence.
GEO.DCPP.01.21 Rev. 2 Page 90 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page ¶2__ of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings Boring 98BA-1 Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay (feet) Description (deg.) (feet) Description rock Fault Bed zone 11.0- "Clay stringers" No televiewer image / 11.4 26.6 Thin clay film (not clay bed) 0-5 ?/? 65.0- Clayey joint coatings 5-30 / 66.0 66.6- Very soft clayey zone (not -67.0 clay bed) 69.4- Clayey rock, 1/8 inch seams; ?? ? 70.0 slickensides, disturbed 87.0 Silty clay in shoe -- ? 90.4 Clay with slickensides, 25 " joint 91.5 Clay coatings with 30 / slickensides, joint 93.7 Clay films, polished, joint 0 / /? 97.6 Clay seam on joint with 25 / slickensides 99.1 Clay on joint with 25 / slickensides 142.8 Joint, 1/16 inch clay, polishe 10 /? /? 145.1- Clayey zone (notbeds)
-- , 145.4 162.0- Soft clayey rock zone Low / 162.2 angle 165.3 Joint with clay, polished .5 ? 170.7 Joint with clay films and 0 V/ VI? slickensides 175.8 1.2 inches clay zone 15 1 _? 192.4- Clay films with slickensides 20 / 192.6 (shear zone) 194.2 Joint with clay films, 0 V/ slickensides 203.3 Bedding with clay seams 5-10 /? 9 ? (films) in 0.7 inch-wide breccia GEO.DCPPO.01.21 Rev. 2 Page 91 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page q.S of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 98BA-2 Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint! Clay (feet) Description (deg.) (feet) Description rock Fault Bed zone 5.9 Joint with clay seam 10 No televiewer image /? ,/? 11.3 Joint with clay seam 30 / 13.3 Joint with clay film 30 ¢" 36.5 Joint with clay film 15 _ _ 38.9 Joint with clay film 15 / 53.4 Joint with thin clay 5 "/ 9 58.2 Joint with thin clay, 30 / slickensides 59.6 Joint with thin clay 5 ¢" ¢_? 63.6 Joint with thin clay, 10 " slickensides 67.3 Joint with clay seams with 10 / shears_ 128.5 Joint with clay films and 0 / slickensides Boring 98BA-3 Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay (feet) Description (deg.) (feet) Description rock Fault Bed zone No clay beds described No televiewer image QEO.DCPPO.01.21 Rev. 2 Page 92 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring OOBA- 1 Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DescpptinDDscritionroc (feet) Description (deg.) (feet) Description rock Fault Bed zone 23.0- Four joints with thin clay 0 23.1 Thin clay (?) bed, 23.2 coatings (altered zone) N25 0 E, 9°NW I land moderately steep joint 30.2 Clay seam (1/8 inch), 0? 29.4- Moderately steep joint, / bedding? 30.2 etched, irregular with clay(?) 51.2 Crushed clayey rock -51.0- Irregular joint, tight / 51.6 54.5 Stiff clay (1/8 inch) -0 53.5- Steep filled joint, irregular
/ 54.5 tight with clay, 55.6- Clay seam (8.4 inches) with -5 54.9- Clay bed with sharp, tight / 56.3 planar rock contacts, 56.2 rock contacts, etched, bedding N82 0 W, 11o-16°S 69.2- Crushed zone with silt, -- 69.2- Steep fracture, eroded, V 69.6 some clay 69.8 clay (?) 79.5 Stiff, silty clay seam (1/8 10 79.2 Possible thin clay along V inch) on joint bedding or joint, etched below N61' E, 11O NW 105.4 Clay seam (1/4 inch) along 15 105.0- Clay seam, etched, V fracture 105.3 irregular top, sharp, smooth bottom contact, N13°W, 12 0 SW 106.5 Silty clay (1/8-1/4 inch), 30 106.4 Tight bedding with V? joint discoloration N20°W, 18°SW 109.5 Clay lined joint 10 108.9- Tight joint / 109.0 140.0- Sandstone, changes to 140.4 Thin clay (?) bed, partly / 141.0 laminations
@ 140.9 etched NI0OE, 4°SW 145.3- Crushed, broken zone with 144.3- Steep joints, tight with / 145.7 clay coatings (1/4 inch) 145.7 clay (1/4-1/2 inch)GEO.DCPPO.01.21 Rev. 2 Page 93 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring OOBA-2 Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Dip Depth Clayey Joint/ Clay DethDscitinDescription rock deg.) (feet) Fault Bed zone 29.8- Crushed zone 29.8- Subhorizontal soft clay (?) V/ V? 30.0 30.2 zone, etched, irregular contact 40.4 Crushed zone 40.4- Moderately steep, joint, / 40.8 partly open and etched, with thin clay (?) 52.4 Clay (1/16 inch) on joint, 0 52.4- Tight, moderately steep / _ minor striations 1 52.6 joint Boring OOBA-3 Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DphDescription Dp ethDescription rock (feet) (deg.) (feet) zone Fault Bed zone 11.8- Clayey sandstone (not a clay No televiewer image / 12.8 bed) 22 Clay film on joint, polished 30 __ 26.5 Clay (1/16 inch) with 0 / /? slickensides, joint Boring 01 CTF-A Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DphDescription Dp ethDescription rock (feet) (deg.) (feet) zone Fault Bed zone 22.9 Clay film on joint, polished 30 22.6- Moderately dipping joint, / 23.0 tight, thin clay (?) 32.4- Soft clayey sand, bedding (?) 30 32.7- Soft clayey (?) zone, etched, / 32.6 33.5 irregular contacts 37.7 Clay (1/16 inch) on joint, 30 38.3- Tight, steep joints / polished, slickensides
_ 40.7 38.2 Clay film on joint, end of '-5 38.3- Tight, steep joints V/ core run 40.7 50.5- Clayey rock zone, not 10 51.1- Low-angle band (murky / 50.6 bedding clay 51.3 water)GEO.DCPPO.01.21 Rev. 2 Page 94 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page aL of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-A Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DesciptonDDesripionroc (feet) Description (deg.) (feet) Description rock Fault Bed zone 15.2- Clay (0.4 inch) in fracture 25-30 15.2- Moderately dipping joint, / 15.4 15.4 eroded, with clay (?) 29.9 Clay layer (0.6 inch), joint 30 29.6- Moderately dipping joint, / 29.9 etched to eroded, thin clay (?) (image distorted) 37.7- Two clay coatings (1/16 inch) 20-30 36.7 Low to moderate dipping ? /? 37.8 on joints joint or bedding (?), etched N40-W, 20-SW 42.1 Sandstone, no recovery -41.0- Textural change, etched, V9 41.1 bedding (?) with clay (?) 42.2- Moderately dipping joint '? 42.3 below broken, eroded zone with thin clay (?) N19°W, 23°W 46.0 Faults with clay coatings, 18-25 44.2- Eroded and etched zone / slickensides 49.2 irregular, near vertical joint 48.2 Clay layer (1 inch) in 0 44.2- Eroded and etched zone '7? broken zone 49.2 irregular, near vertical joint 52.0- Sandstone with joints 0 53.3 Low-angle joint, eroded with / 53.9 thin clay 54.9 Silty clay with sand and 20 54.1- Low-angle bedding with / gravel (1 inch), bedding? 54.3 textural difference, etched and eroded, 1/2-to 1 inch clay bed (?) N69 0 E, 7°NE 55.8 Faults with thin clay 8-20 55.3 Bedding (?), etched, with V'? coatings, slickensides thin clay (?) bed NI 1-W, 22°W 58.8 0.4 inch clay layer 20 58.5 Subborizontal clay layer, '? eroded and etched, irregular, 1/4-1/2 inch thick, bottom Nl1 0 W, 22°W_GEO.DCPPO.01.21 Rev. 2 Page 95 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 00 of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-B Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DescpptinDDscritionroc (feet) Description (deg.) (feet) Description rock Fault Bed zone 43.3 Trace clay on two joints 0 43.3 Broken rock zone V, 48.7 Trace clay on joint 30 48.7 Broken rock zone / Boring 01-C Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Description Dip Depth Description Clayey Joint/ Clay (feet) (deg.) (feet) rock Fault Bed zone 16.3 Clay film on joint 15 15.9(?) Low-angle bedding, etched, V? with clay (?) (-1/8 inch) I_ N73°W, 15 0 S 23.8 Joint 5 23.7- Bedding, eroded, with clay / 23.8 (?) (-1/4 inch) N66°W, 15°SW 41.1- Clay films on two joints, 20-30 40.3- Moderately steep joint, " 41.4 slickensides 40.5 etched, no visible clay 44.1 Clay (0.2 inch) on bedding? 0-5 43.6 Subhorizontal bedding, etched to eroded, thin clay (?), irregular 55.8- Sandstone some clay 5 54.9 Subhorizontal, irregular 56.2 bedding (?), etched to eroded, clay (?) 65.3 Soft clay (1/4 inch) on joint, 5 65.0 Moderately steep joint, / bedding (?) etched, slight clay (?) I _ (water in hole, image fuzzy)December 14, 2001 GEO.DCPPO.01.21 Rev. 2 Page 96 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 'LS of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-D Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DescriptionDrock (feet) Description (deg.) (feet) Description rock Fault Bed zone 26.5- Joint, crumbly zone 30 25.9- Eroded zone between two / 27.0 26.9 moderately steep joints, clayey (?), rock (6.25 inches wide) 55.0- Crushed zone with clay, 53.4- Eroded and etched zone V/? 55.5 joint at 55.2 54.9 (clayey?), rough bedding (?) I at base N33°W, I IN Boring 01-E Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Description Dip Depth Description Clayey Joint/ Clay (feet) (deg.) (feet) rock Fault Bed zone 12.85 Clay layer (1/8 inch) 10 12.1- Vein, joints, etched, / 112.7 clayey (?) 20.8 Clay gouge (1/16 inch), 30 20.4- Shallow joint, etched, / joint 20.5 irregular, with thin clay (?) 23.0- Zone of clay coated joints, 30 23.1- Moderately steep, tight to / 25.0 polished, with rubble 24.3 slightly etched, joints 71.7 Clay film on joint 30 71.4- Steep, tight joint (hole has / 72.1 water, image fuzzy) 77.4 Clay filled joint 0 77.0- No joints evident (hole has / 78.0 water, image fuzzy)GEO.DCPPO.01.21 Rev. 2 Page 97 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page It'1 of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-F Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DesciptinDDscritionroh (feet) Description (deg.) (feet) Description rock Fault Bed zone 5.5 Clay film (<1/16 inch), joint 0 4.7- Fractured zone with clay (?) / 6.6 6.8 Clay film (<1/16 inch), joint 20 6.6 Partly open joint with thin V/? V/? clay (?), shallow bedding (?) N70oW, 9°SW 10.5- Sandy, clayey rock zone 10.2- Partly etched zone / 10.8 10.5 16.1- Fractured clayey zone 15.2- Weak, etched and eroded V/ 16.3 16.4 rock 29.2 Clayey crushed rock mixed 29.0- Weak, etched zone ? with harder rock fragments 30.2 35.5- Clayey fractured zone, 35.0- Soft, partly etched, locally / 38.0 altered 38.0 fractured rock 43.8- Clayey fractured zone, 0-10 43.7- Fractured rock with tight, / / 44.4 altered 80-90 45.3 subhorizontal joint and steep, partly open joints, some clay (?) 46.6- Clayey fracture zone, 0 46.0- Steep, eroded joints and " 46.8 altered, bounded by joints 47.0 fractured rock with clay 57.5- Clayey zone along possible 5-15 57.9 Subhorizontal, tight /? /? 57.7 bedding lamination, slight clay (?) _ (<1/16 inch) 58.6 Clay films on joint with 20 57.0- Tight joints and / slickensides, possible 59.0 subhorizontal laminations, bedding possible clay (<1/16 inch) 58.6- Clayey lens in rock and clay 10 58.7- Moderately dipping joint, " " 58.8 films with slickensides, joint 58.9 etched, with clay (?) (<1/16 inch) 94.3- Clayey, silty crushed rock 0-10 93.2 Subhorizontal joint along / 94.4 with clay bed (1/4-1/2 inch bedding, etched, with 1/4 thick) inch clay (?), etched I_ EW, 140S 98.0- Broken zone with clayey- 70 98.0- Fractured zone with V 98.4 silty matrix 99.0 apparent softer rock pockets, eroded (clay ?)GEO.DCPPO.01.21 Rev. 2 Page 98 of 181 December !14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page tLO of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-F (continued)
Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay Desritintoc FaplteBed (feet) Description (deg.) (feet) Description rock Fault Bed zone 103.8 Thin silt/clay coating on 20 103.0- Fractured zone with steep / joint 104.4 joints 104.4 Clay on joint 30 103.0- Fractured zone with steep / 104.4 joints 105.5 Clay seam (?) (<-1/2 inch) in 65-80 105.0- Tight rock with few steep / broken zone (clay in crushed 106.0 fractures, laminations, no zone) clay seam evident 107.3 Trace clay on joint 20 106.5- Solid, unfractured rock, no 108.0 clay or joints evident 111.3 Trace clay on joint 20 111.1- Moderately steep joint, 1/ 111.4 irregular, partial thin clay (?) 111.9 Clay (<1/32 inch) on joint 0 111.5- Moderately steep, hairline 112.5 fracture in otherwise solid unfractured rock 117.0 Clay layer (0.4 inch) bedding 8-12 116.4 Subhorizontal bedding, -/9 (?) etched, possible thin clay (-1/8 inch) N70°W, 6°-12"SW 124.8 Joint lined with 1/16 inch 30 123.6- Tight to open, steep / clay 124.5 joints, no clay evident 125.9 Joint with trace clay, 35 124.5- Tight, sound rock with few / polished 126.5 tight to locally open, steep fractures GEO.DCPPO.01.21 Rev. 2 Page 99 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page L'__ of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-G Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay eepth Description (d ) (eept) Description rock Fault Bed (feet) Dsrpin(deg.) (feet) zn zone 8.6- Weak zone with clay, -- 7.6- Moderately steep joints, V 9.0 crushed 8.6 partly brQken out, with thin clay (?), massive rock below 14.3 Clay lined joints 30 14.0- Tight, moderately steep " 14.2 joint, no visible clay 18.7 Clay seam (1/2-3/4 inch) Top, 18.5 Subhorizontal, tight / above broken rock zone on --0; bedding laminations bedding (?) Base, possible thin (<1/4 inch 0-5 clay) (?), N22°W, 13°SW 25.4 Joint with clay coatings 0- 25.0 Subhorizontal bedding, / (<0.5 inch) -15 tight with thin clay (?) 1 _ (<1/8 inch), N78°W, 15'S 29.1 Joint with very thin film 0 28.8 Bedding (?), partly broken out in zone of massive rock N60oW, 12-SW 50.3 Zone of silty clay -- 49.2- Steep, partly open joints ? 50.6 and broken rock 56.3 Clayey fracture zone 0-10 55.8- Steep joints and broken / parallel to laminations 57.5 rock, localized clay (up to i-1/2 inch) on joint 67.2 Minor clay/silt laminations
-- 67.0- Laminated tight rock with / 68.0 steep joint, no visible clay 75.6 Thin clay film on joints 30-40 1 Below televiewer log _ _December 14, 2001 GEO.DCPPO.01.21 Rev. 2 Page 100 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page _La of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-H Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay Det) Description Description rock (feet) (deg.) (feet) zone Fault Bed 10.0 Clay films 30 9.2- Moderately dipping joint / 9.4 partly broken out, with some clay (?) 39.4 Two very thin clay layers 10 39.4 Subhorizontal bedding, V/ between fracture blocks slightly etched, with thin clay (?), N30°W, 15WSW 40.3 Joint with thin clay coating 13 39.6- Massive, laminated rock 41.0 50.5 Clay "clast" (1/4-3/4 inch), 30 49.7- Massive rock, no clay V/ bedding parallel 51.6 evident, thin, slightly etched beds at 50.3 and 50.4 59.9 Clay layer (1/8 inch thick) -- 59.1- Subhorizontal softer rock ? 59.8 zone, etched contact, vague 67.2 Clay layer (1/8 inch thick) 30 66.7- Moderately dipping joint, / 66.9 slightly etched, with thin clay_ () (<1/16 inch) _ 67.4 Clay layer (1/8 inch thick) 30 66.7- Moderately dipping joint / 66.9 with thin clay (?) (<1/16 inch) 72.8 Clay on joint (1/16 inch 30 72.2 Irregular, thin clay (?) /? 9? thick) layer in massive rock 82.3 Clay seam (3/4 inch thick) 0 81.4 Subhorizontal bedding ? laminations, tight, no clay evident, N45°W, 12°SW 89.6 Sandstone (1/16 inch clay 0 88.8 Bedding, textured change, V/ bed twisted by drilling)
N67°W, I I°SW 94.5 Dark gray clay layer (1/4 10-30 93.6 Subhorizontal bedding, / inch thick) eroded with clay (?) (-1/4 inch), N38 0 W, 21°SW GEO.DCPPO.01.21 Rev. 2 December 14, 2001 Page 101 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page t10of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-I Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay DescriptionDrock (feet) Description (deg.) (feet) Description rock Fault Bed zone 15.6 Clay on joint (0.2-0.4 inch) 10 15.0- Broken zone, clay (?) along V/ 16.0 *oints 18.9 Clay on joint (1/16 inch) 0 17.8- Broken out zone along steep / 120.0 joints, clay (?) 20.2 Silty/clayey crushed rock 10-20 20.4- Broken, jointed zone I zone (not clay bed) 21.0 33.9 Clay film (1/16 inch) on 10 34.9 Subhorizontal lamination, / bedding, joint (?) tight to partly eroded bedding, N39OE, 6°NW 39.0- Crushed zone with silt, clay 37.9- Fractured zone, steep joints, / 40.0 films 40.1 partly broken out 43.1 Clay on joint (1/4 inch) 20 43.4- Thin clay, eroded and / 43.6 etched along bedding (?), N55 0 E, 18'NW 45.6 Clay bed (0.8 inch) 10-15 46.2 Well imaged thin clay, $ etched, bedding parallel, N54°E, 14°NW 48.1 Clay seam (0.4 inch) on joint 10-20 48.8 Subhorizontal joint/clay
/ associated with CaCO 3 seam, etched, with clay vein (1/4-1/2 inch), N50 0 E, 13°NW 57.2 Sandy crushed zone 57.6- Subhorizontal, planar / 57.9 opening along eroded soft rock zone (1/2 to 1 inch); thin clay (?) along base, bedding, N25'E, 8'-15°NW 61.0- Crushed rock zone with -60.0- Steep joints with clay (?) / 61.4 some clay, not bedding 62.5 62.7- Crushed rock zone with silt 63.3- Moderately steep, smooth / 63.1 and clay, not bedding 63.9 joints with crushed and weak rock mixed with clay (?) in lower part 1(-2 inch thick)dEO.DCPPO.01.21 Rev. 2 Page 102 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page tA'of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-I (continued)
Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay (feet) Description (deg.) (feet) Description rock Fault Bed zone 68.6- Clay zone with crushed 68.3- Moderately steep to steep / 69.2 altered rock (not bedding) 70.2 joints bounding I foot-thick, weak rock, deeply eroded with possible clay 70.8- Crushed zone with clay 70.5- Moderately steep / 71.1 70.8 fracture, partly open, with clay (?) 85.8 Trace clay on joint 20 85.4- Moderately steep, open / 85.6 joint, possible thin clay washed out? 90.1 Clay (0.1-0.2 inch) on 20 89.2- Massive unjointed rock / joint 90.7 with laminations
_ 1 93.4- Three joints with trace clay 30 93.4- Steep joints, with thin / 93.9 94.6 clay (?), partly eroded and bounded by massive unjointed rock with color laminations 100.2- Trace clay on two joints 20 98.0- Fractured rock with steep / 100.6 100.8 open joints, discontinuous 106.6 Clayey/silty/sand seam 10-12 106.4 Subhorizontal clayey seam / (-3/4 inch), bedding (1 to 2 inches thick), eroded and etched along bedding N19 0 W, 12 0-14 0 W 108.9 Broken clay along joints 18-20 108.0- Broken rock zone with / 116.2 steep joints, clay (?)__ 110.0 Sandy clay (0.4 inch) at 108.0- Broken rock zone with / bottom of run, possible 116.2 steep joints, clay (?) slough 123.0 Joint with 0.2 inch clay 20 121.1- Broken rock zone, / 124.1 subhorizontal fabric, possible thin clay (?) laminations 123.8- Clayey sandstone bed above 10-20 124.1 Irregular bedding contact ,/ 124.1 coarse, 1.2 inch-thick between broken rock and sandstone bed soft, granular rock, eroded, I _N46°W, 16-NE GEO.DCPPO.01.21 Rev. 2 Page 103 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page (64' of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-I (continued)
Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay (feet) Description (deg.) (feet) Description rock Fault Bed zone 127.6- Crushed clayey zone (2.4 20-35 126.5- Steep joints and broken / / 127.8 inches) 129.2 rock, partly open, with clayey (?) zone at 127.8 130.3 Stiff clay seam (1/4-1/2 inch) 10 Bedding with clay (?) / along bedding I _ slightly etched N12°E, 3YS 131.0 Joint with clay 20 131.6 Bedding with thin clay, V9 subhorizontal, N81°E, 8 0 S 146.3 Clay (1/8 inch) on joint (or 20 145.2- Open, steep joint, eroded, V/? drilling clay?) 148.7 possible washed-out soft rock or clay zone 151.4- Crushed silty/clayey zone, -- 149.5- Fractured rock, partly open / 151.9 -,part slough? 151.2 and etched 156.1 Shaley seam (1/4 inch) with 15-18 156.5- Softer rock zone, eroded V9 slickensides along bedding 156.8 and etched, subhorizontal, contact possible clay at base of zone, bedding N65*E, 12 0-18 0 NW 167.4- Zone with multiple clay 10 167.0 Thin clay (?), etched along / 167.8 seams (1/8-1/4 inch) along bedding bedding 171.0- Crushed zone with silty clay 10 170.0- Clear laminations and steep, V 171.2 in joint (1/8 inch), possible 172.0 partly open joints with slough at bottom clay N20*E, 12 0 NW 185.0- Two clay beds (0.8 inch; 10-20 185.7- Subhorizontal clay bed " 185.3 0.4 inch) with crushed zone 186.1 (4.8 inches-thick), etched between N47°E, 12°-14°NW 188.5 Clay film (1/16 inch) on joint 10 188.0- Solid rock with color V? 189.0 laminations, slightly etched, N3°W, 7°E _December 14. 2001 GEO.DCPPO.01.21 Rev. 2 Page 104 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page L O__of 185 Table 21-2 Evaluation of Clay 'Seams' on Low-Angle Fractures and Bedding, ISFSI Study Area Borings (continued)
Boring 01-I (continued)
Log of Rock Boring NORCAL Televiewer Imaget Interpretation* (DCPP ISFSI Data Report B) (DCPP ISFSI Data Report E) Depth Dip Depth Clayey Joint/ Clay (feet) Description (deg.) (feet) Description rock Fault Bed zone 197.0 Clay films on joint 0 196.0- Massive rock with color 198.0 laminations, slight etching at 197.1, N20°E, 12°NW 210.2 Crushed clayey, sandy zone -- 209.0- Broad color laminations and / / at top of crushed zone 211.0 near-vertical joint with clay (?) 215.8- Crushed zone with clay -- 215.9- Irregular, subhorizontal i 216.0 seam, slickensides 216.4 bedding with brown clay (1 inch), eroded and etched, bottom contact N4 0 E, 29 0 W 223.1 Clay film on joint 0 221.1- Massive rock with weak 223.8 color laminations, moderately dipping, tight joint at 223.8 230.7 Irregular clay seam/bed (?) 5-15 230.2- Steep joint with clay (?) ? (0.4 inch) 231.0 230.9 Top of light color band, ,etched, clay (?) 236.3 Stiff clay seam (0.4 inch) on 15 236.8 Subhorizontal clay (1/4-1/2 / bedding inch) along laminations, etched and squeezing into hole N17°W, 13°SW 245.1 Clay on join (0.4 inch) 0 244.8- Massive rock with a steep, 246.2 tight to slightly open joint 289.9- Clay seam/bed (0.2-0.4 inch) 10-15 290.4 Subhorizontal clay bed V/ 290.1 (1/4-1/2 inch) along laminations, etched _N62°E, 18°NW Note: Clay on fractures steeper than 30 degrees are not included because bedding has dips less than 20 degrees in the site area. t Bedding attitudes from Table 21-1
- Interpretation Categories Bold type highlights clay bed or possible clay bed shown on cross sections /Significant clay bed (> 1/4 inch thick, follows bedding; thickness in most cases taken from measurements on core) / Clay along bedding, joint or fault v/? Probable clay along bedding, joint or fault ? Possible clay along bedding, joint or fault December 14, 2001 GEO.DCPPO.01.21 Rev. 2 Page 105 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page of 185 Table 21-3 Thickness Measurements of Clay Beds in Borings and Trenches Thickness (inches)a minimum maximum 0.06 0.06 Location 98BA- 1 98BA-I 98BA-1 98BA-1 98BA-1 98BA- 1 98BA-1 98BA-2 98BA-2 98BA-2 98BA-2 98BA-2 98BA-2 OOBA-1 OOBA-1 OOBA-1 OOBA-i OOBA- 1 OOBA- I OOBA-2 OOBA-3 01-A 01-A 01-A 01-A 01-A 01-C 01-C 01-C 01-F 01-F 01-F 01-F 01-G 01-G 01-G Notes on Boring Depth (feet) 93.7 142.8 165.3 170.7 175.8 194.2 203.3 5.9 53.4 59.6 63.6 67.3 128.5 23.0-23.2 55.6 to 56.3 79.5 105.4 106.5 140.0 to 141.0 29.8-30.0 26.5 37.7-37.8 42.1 54.9 55.8 58.8 16.3 23.8 44.1 6.8 57.5-57.7 94.3 to 94.4 117 18.7 25.4 29.1______________
.1 ______________
Page 106 of 181 December 14, 2001 GEO.DCPP.0 1.21 Rev. 2 Trench Station (meters) na na na na na na na na na na na na na na na na na na na na na na na na na na na na na na na na na na na na 0.06 0.06 0.06 0.25 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 8.40 0.12 0.25 0.12 0.06 0.12 0.06 0.06 0.06 0.50 0.06 0.25 0.06 0.25 0.06 0.06 0.06 0.25 0.12 0.12 0.12 0.06 0.06 0.06 0.06 1.20 0.06 0.06 0.12 0.12 0.12 0.12 0.12 0.06 0.12 8.40 0.12 0.25 0.25 0.06 0.25 0.06 0.06 0.12 1.00 0.12 0.50 0.06 0.25 0.20 0.06 0.06 0.50 0.40 0.25 0.12 0.06 I I Notes on Thicknessb 1,2 1,2 1,2 1,2 1 1,2 3,2 3 3 3 3 3 1,2 3 1 1 ! 1,2 3 1,2 1,2 3 3 1,2 1 3 1,2 1,2 6 6 1,2 Subunitc Tofb.2 TOfb-2 Tofb.2 Tofb.2 Tofb-2 Tofb.2 Tofb.2 Tofb-2 Tofb.2 Tofb.2 Tofb.2 Tofb.2 Tofb-2 Tofb., Tofb, Tofb-I Tofb-I Tofb-I Tofb.I Tofb-i Tofb-Z Tofb.2 Tofb.2 Tofb.2 Tofb.2 Tofb-2 Tofb.2 Tofb-2 Tofb.2 Tofb., Tofb-2 Tofb.2 Tofb.I and Tofb-la Tofb.I Tofb.I Tofb.,
Calculation 52.27.100.731, Rev. 0, Attachment A, Page JQ of 185 Table 21-3 Thickness Measurements of Clay Beds in Borings and Trenches Boring Depth Trench Station Thickness (inches)a Notes on Location (feet) (meters) minimum j maximum Thicknessb Subunit____________
I I I 01-H 01-H 01-H 01-H 01-H 01-I 01-I 01-I 01-I 01-1 01-I 01-I 01-I 01-I 01-I 01-I 01-1. 01-I 01-I 01-1 01-I 01-I 01-1 01-I T-I IA T-IIA T-l IB T-I1 C T-lID T- 12 T-14A T-14A T-14B T-15 T-18A T-19 December 14, 2001 GEO.DCPP.01.21 Rev. 2 na na na na na na na na na na na na na na na na na na na na na na na 39.4 59.9 72.8 89.6 94.5 33.9 43.1 45.6 48.1 57.2 106.6 130.3 131 156.1 167.4-167.8 185 185.3 188.5 197.0 215.8 to 216.0 223.1 230.7 236.3 289.9 to 290.1 na 0.06 0.12 0.06 0.06 0.25 0.06 0.25 0.06 0.25 0.06 1.00 0.25 0.06 0.25 0.12 0.40 0.80 0.06 0.06 1.00 0.06 0.40 0.25 0.25 0.06 0.20 0.20 0.20 0.20 0.06 1.00 0.25 2.00 2.00 0.06 0.25 na na na na na na na na na na na na na 3.0 to 7.5 7.5 to 11.0 0.5 to 5.4 -I to 2.3 0 to 8.5 4.5 to 11.0 0 to 8.5 8.5 to 22.0 0.00 to 4.00 6.0 to 19.0 1.0 to 4.5 11.8 to 17 0.00 0.12 0.06 0.06 0.25 0.06 0.25 0.80 0.50 0.12 2.00 0.50 0.12 0.25 0.25 0.40 0.80 0.06 0.06 1.00 0.06 0.40 0.50 0.50 0.12 0.80 0.60 0.60 0.80 0.25 4.00 2.00 4.00 4.00 0.25 0.25 Page 107 of 181 I 3 3 6 3 1,2 1 1,2 1 5 4 5 4 4 5 5 5 7 4 4 4 To fb.2 Tofb.2 Tofb.2 Tofb.2 Tofb., Tofb.I Tofb.I Tofb., Tofb.-I Tofb.i Tofb.I Tofb., Tofb.I Tof~b.I Tofb.I To fb. I Tofb.I Tofb., TofbI Tofb.i, Tofb., Tofb.i Tofb-, Tofb.i and TOfb.ia TofbI. and Tofb-ia Tofb.I and Tofb-ia Tofb.i and Tofb.,a Tof" and To TOfb., and Tofb-,ý Tofb.I , Tofb.I Tofb.I Tofb., Tofb.,
Calculation 52.27.100.731, Rev. 0, Attachment A, Page 011_ of 185 Table 21-3 Thickness Measurements of Clay Beds in Borings and Trenches (continued)
STATISTICS ON CLAY BED THICKNESS Measurements from boreholes and trenches number of thickness measurements
= minimum thickness
= maximum thickness
= median thickness
= mean thickness
= I standard deviation
=minimum 72 0.06 8.40 0.09 0.35 1.03 maximum 72 measurements 0.06 inches 8.40 inches 0.23 inches 0.59 inches 1.25 inches Trench Data Cumulative length of clay beds exposed in trenches (feet) (minimum because clay beds extend beyond end of trench)-<
1/4 inch thick> 1/4 inch thick Total Boring Data Number of clay beds encountered in borings< 1/4 inch thick > 1/4 inch thick Total= 64.64 feet (28%)= 169.96 feet (72%) 234.60 feet (100%) = 44 (73%) = 16 (27%) 60 (100%)F measurements taken from trench exposures and borings; thicknesses may not represent the true ranges for individual beds b Tofb.I =dolomite subunit, Tofb-j 1 = friable dolomite subunit, Tofb.2 = sandstone subunit C Notes on thickness
- 1. Only a single measurement taken; this value used in both minimum and maximum columns 2. Field description of film as "very thin"; assumed thickness of 0.06 (1/16) inch 3. Field description of "thin" given range of 0.06 to 0.12 inches 4. Thickness range recorded in trenches reflects two discrete measurements made along clay bed. 5. Thickness range is estimated from notes on trench logs 6. Thickness estimates using televiewer information only (boring log not used). 7. Thickness measured from photographs.
December 14, 2001 GEO.DCPP.01.21 Rev. 2 Page 108 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page tlo of 185 Table 21-4. Friable Rock Zones in ISFSI Study Area Borings.Depth Interval Test Sample of friable rock I.D. (feet)Elevation Interval (feet)Friable Zone Interval Thickness (ft)98BA-1 Total Borehole Denth =Elevation at ground surface 90.0-96.0 118-133.5 138.7-140.0 142.8-145.2 167.3-172.3 182.3-200.0 206.0-206.8 372.0 282.0-276.0 254.0-238.5 233.3-232.0 229.2-226.8 204.7-199.7 189.7-172.0 166.0-165.2 Total Friable Zone 250.0 Interval Footage =Elevation at ground surface 5.0-15.0 46.5-48.5 56.6-60.0 65.0-68.0 70.0-89.0 96.Q-97.0 103.5-107.2 146.0-150.0 322.0 317.0-307.0 275.5-273.5 265.4-262.0 257.0-254.0 252.0-233.0 226.0-225.0 218.5-214.8 176.0-172.0 Total Friable Zone Depth = 165.0 Interval Footage = 46.1 % Friable = 27.9 98BA-3 Elevation at ground surface 322.0 171.6-175.0 150.4-147.0 3.4 205.0-212.0 117.0-110.0 7 Total Borehole Total Friable Zone Depth = 220.0 Interval Footage = 10.4 % Friable = 4.7 OOBA-1 Elevation at ground surface 450.0 29.0-34.0 421.0-416.0 5 Total Borehole Total Friable Zone Depth = 150.0 Interval Footage = 5.0 % Friable = 3.3 OOBA-2 Elevation at ground surface 363.0 0.0-32.0 363.0-331.0 32.0 38.2-40.6 324.8-322.4 2.4 42.0-47.5 321.0-315.5
5.5 Total
Borehole Total Friable Zone Depth = 55.0 Interval Footage = 39.9 % Friable = 72.5 December 14, 2001 GEO.DCPP.01.21 Rev. 2 Boring 6.0 15.5 1.3 2.4 5.0 17.7 0.8 48.7 98BA-2 Tn~t~l llnrehnle% Friable =19.5 10.0 2.0 3.4 3.0 19.0 1.0 3.7 4 Page 109 of18S1 (feet)Denth =
Calculation 52.27.100.731, Rev. 0, Attachment A, Page[ _ of 185 Table 21-4 Friable rock zones in ISFSI Study Area borings. (continued)
Boring Depth Interval Test Sample of friable rock I.D. (feet'l Elevation Interval (feet)Friable Zone Interval Thickness (ft)OOBA-3 Elevation at ground surface 306.0 4.0-5.6 302.0-300.4 1.6 11.1-12.8 294.9-293.2 1.7 21.6-24.0 284.4-282.0
2.4 Total
Borehole Total Friable Zone Depth = 30.0 Interval Footage = 5.7 % Friable = 19.0 01CTF-A Elevation at ground surface 306.1 6.3-10.6 299.8-295.5 4.3 18.0-24.7 288.1-281.4 6.7 34.4-35.8 271.7-270.3 1.4 37.7-39.5 268.4-266.6 1.8 48.5-58.6 257.6-247.5 10.1 Total Borehole Total Friable Zone Depth 58.6 Interval Footage = 24.3 % Friable = 41.5 01-A Elevation at ground surface 305.7 5.4-6.5 300.3-299.2 1.1 26.2-28.4 279.5-277.3 2.2 33.4-37.0 272.3-268.7 3.6 46.2-48.8 259.5-256.9 2.6 58.8 -59.0 364.5 -364.7 0.2 70.0-71.6 235.7-234.1
1.6 Total
Borehole Total Friable Zone Depth 71.8 Interval Footage 11.3 % Friable 15.7 01-B Elevation at ground surface 318.9 38.0-39.8 280.9-279.1 1.8 54.5-57.0 264.4-261.9
2.5 Total
Borehole Total Friable Zone Depth 72.0 Interval Footage 4.3 % Friable = 6.0 01-C Elevation at ground surface 323.0 7.0-14.0 316.0-309.0 7.0 40.4-42.0 282.6-281.0
1.6 Total
Borehole Total Friable Zone Depth = 67.0 Interval Footage = 8.6 % Friable = 12.8 December 14, 2001 GEO.DCPP.01.21 Rev. 2 Page 110 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 10-of 185 Table 21-4. Friable rock zones in ISFSI Study Area borings. (continued)
Depth Interval of friable rock Test Sample I.D.Elevation Interval (feet)Friable Zone Interval Thickness (ft)01-D Elevation at ground surface 325.2 22.0-37.6 303.2-287.6 15.6 67.0-68.5 258.2-256.7
1.5 Total
Borehole Total Friable Zone Depth = 68.5 Interval Footage = 17.1 % Friable = 25.0 01-E Elevation at ground surface 337.6 4.7-14.0 331.3-323.6 9.3 39.2-43.0 298.4-294.6 3.8 68.4-80.7 269.2-256.9 12.3 Total Borehole Total Friable Zone Depth = 81.0 Interval Footage = 25.4 % Friable = 31.4 01-F Elevation at ground surface 390.6 33.0-33.9 357.6-356.7 0.9 37.0-38.0 353.4-352.6 0.8 43.8-45.0 346.8-345.6 1.2 46.6-47.4 344.0-343.2 0.8 57.6-60.0 333.0-330.6 2.4 103.0-106.0 287.6-284.6 3.0 117.0-121.8 273.6-268.8 4.8 123.0-124.2 267.6-266.4 1.2 130.0-130.5 260.6-260.1
0.5 Total
Borehole Total Friable Zone Depth = 130.5 Interval Footage = 15.6 % Friable = 12.0 01-G Elevation at ground surface 316.8 11.0-12.4 305.8-304.4 1.4 19.2-20.4 297.6-296.4 1.2 24.2-25.6 292.6-291.2 1.4 66.0-76.0 250.8-240.8 10 Total Borehole Total Friable Zone Depth = 76.0 Interval Footage = 14.0 % Friable = 18.4 GEO.DCPP.01.21 Rev. 2 Boring December 14, 2001 Page 111 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1\3 of 185 Table 21-4. Friable rock zones in ISFSI Study Area borings. (continued)
Boring Depth Interval Test Sample Friable Zone of friable rock I.D. Elevation Interval Interval (feet) (feet) Thickness (ft) 01-H Elevation at ground surface 346.6 12.0-12.6 334.6-334.0 0.6 23.7-24.0 322.9-322.6 0.3 29.4-32.0 317.2-314.6 2.6 55.5-58.6 291.1-288.0 3.1 61.0-61.2 285.6-285.4 0.2 81.0-83.0 265.6-263.6 2.0 89.2-98.2 257.4-248.4
9.0 Total
Borehole Total Friable Zone Depth = 101.0 Interval Footage = 17.8 % Friable = 17.6 01-I Elevation at ground surface 566.9 33.6-39.8 533.3-527.1 6.2 61.0-61.4 505.9-505.5 0.4 62.7-63.0 504.2-503.9 0.3 68.5-69.1 498.4-497.8 0.6 109.0-115.8 457.9-451.1 6.8 155.6-156.6 411.3-410.3 1.0 252.4-252.8 314.5-314.1
0.4 Total
Borehole Total Friable Zone Depth = 321.0 Interval Footage = 15.7 % Friable = 4.9 December 14, 2001 GEO.DCPP.01.21 Rev. 2 Page 112 of !181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1W of 185 Table 21-5 Discontinuity Data for Minor Faults' Fault Slickensides Trench/Field Trench Fault Fault Striation (s) or Number Location Strike Dip Rake mullions (m) Person and Date T-l St. 23 170 85 S 50OS m JLB 6/9/00 T-1 St. 24 297 72 S 5-10 W s CMB 6/9/00 T-2A St 0.4 279 70S 8 E m JLB 6/11/00 T-2A St. 15 286 75 NE 20 W s JLB 6/11/00 T-2C St. 3.6 281 70 N 68 E s JNB/CMB 6/20/00 T-2C St. 1.2 264 84 S 15 W s JNB/CMB 6/20/00 T-2C St. 0 280 70 S 0 s JNB/CMB 6/20/00 T-2C St. 0 295 80 S 0 s JNB/CMB 6/20/00 T-3 St. 7.5 295 55-75 S 18 SE ml WDP 7/10/00 T-5 St. 18 70 85 N 2 E s WDP 8/2/00 T-7 St. 3.6 265 65 N 15 E s JLB 6/12/00 T-1IA St. 6 304 81 S 43 E s RDK 8/8/00 T-11A St. 2.4 282 87 N Subhor. s RDK 8/8/00 T-1 iC St. 3.5 85 73 S Subhor. s JNB 6/19/00 T-12 St. 4 291 75 N 1OE s JNB 6/20/00 T-12 St. 4 291 75 N 8 E m JNB 6/20/00 T-12 St. 4.7 300 56 S 10 E s JNB 6/20/00 T-12 St. 14 292 60 S 10 W s JNB 6/20/00 T-13 St. 6.5 301 44S loW s JNB 6/20/00 T-14B St. 1.0 95 81 N 0 m JLB 8/7/00 T-14B St. 1.5 101 86 S Subhor. m JLB 8/7/00 T-14B St. 2.0 104 88 N Subhor. mn JLB 8/7/00 T-15 St. 18.5 297 83 N Subhor. s JNB 6/20/00 T-17A St. 41 265 84 N 65 W s JLB 8/2/00 T-17A St. 39 296 80 N 47 W s JLB 8/2/00 T-17A St. 45.5 254 65 N Subhor. s JLB 8/2/00 T-17A St. 11 90 85 S Subhor. s JLB 8/2/00 T-18B St. 7.5 300 86-90 S Subhor.-45 M. JLB 8/23/00 "T-20A St. 26 298 63S 16 SE s JLB 11/30/00 T-20B St. 3.2 273 61 S 16 W s JLB 12/6/00 JLB 4/16/01 WRLL T-21 St. 20.5 286 80 N Subhor. s 41T'R/f1 Field 1 Diablo Canyon Rd. cut 305 75 N Subhor. m+s WRL across from Raw Water Reservoirs and along projection of ISFSI site faults.December 14, 2001 GEO.DCPP.01.21 Rev. 2 Page 113 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page MS of 185 Table 21-5 Discontinuity Data for Minor FaultsI (continued)
Fault Slickensides Trench/Field Trench Fault Fault Striation (s) or Number Location Strike Dip Rake mullions (m) Person and Date Field 2 Diablo Canyon Rd. cut 305 75 N 10 E m+s WRL/JLB/WDP across from Raw Water 5/17/01 Reservoirs and along projection of ISFSI site faults. Confirmed with JLB- 17-1 station GPS 023 N 350 51.264' W 1200 51.264'.
JLB- 17-2 296 80 N 10 E m (?) WRL/JLB/WDP GPS 024 N35 0 12.927' W120 0 51.234'. North wall of Diablo Canyon. Fault is any discontinuity along which displacement of rock has occurred.GEO.DCPP.01.21 Rev. 2 Page 114 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page W.\ of 185Table 21-6 Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches.GEO.DCPP.01.21 Rev. 2 Dip Depth(" of Boring(" ID" 2) Dip(3) Direction(4)
Fracture OOBA-1 35 36.5 86 86.763 continued 36 68.0 253 86.297 37 36.2 235 83.310 38 38.1 221 83.292 39 63.7 229 80.387 40 61.7 252 79.791 41 72.0 201 78.688 42 60.9 205 76.367 43 52.9 201 75.547 44 61.0 213 75.241 45 33.9 221 73.429 46 77.6 186 72.946 47 38.2 40 72.034 48 42.7 50 71.330 49 68.5 233 71.055 50 61.1 353 69.457 51 68.6 261 62.156 52 61.6 40 60.866 53 44.7 202 59.012 54 63.6 353 54.100 55 64.6 218 52.725 56 31.4 192 52.470 57 65.7 360 51.869 58 79.2 196 49.721 59 70.9 4 48.368 60 70.7 233 47.689 61 59.0 238 47.077 62 24.4 16 45.703 63 73.7 215 25.729 64 75.3 242 23.770 65 49.6 232 23.152 66 37.3 196 18.001 67 65.5 214 13.289 Page 115 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1i0 of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Depth(5) of Boring") ID(2) Dip(3) Direction(4)
Fracture OOBA-2 1 40.5 205 53.453 2 18.6 267 50.147 3 74.1 223 48.521 4 48.9 237 40.597 5 67.7 205 39.467 6 66.8 214 39.208 7 41.9 232 39.113 8 40.5 240 38.731 9 44.2 282 35.604 10 48.1 272 34.321 11 72.0 101 27.219 12 71.0 120 26.263 13 64.0 224 9.438 Dip Depth 5 , of Boring4')
Id 2) Dip(3) Direction(4)
Fracture OICTF-A 1 51.3 205 45.134 2 55.1 250 44.431 3 69.6 212 34.263 4 55.1 216 31.310 5 35.7 151 19.592 GEO.DCPP.01.21 Rev. 2 Dip Depth 5' of Boring(')
ID(2) Dip(3) Direction(4)
Fracture 01-A 1 70.5 264 69.083 2 61.2 240 68.545 3 76.6 235 68.240 4 64.8 265 57.922 5 49.8 199 57.577 6 37.5 257 56.422 7 35.7 358 53.227 8 69.3 184 52.954 9 67.6 249 51.988 10 64.5 248 51.772 11 29.4 182 51.682 12 58.1 194 51.196 13 34.4 55 50.081 14 48.3 39 44.392 15 35.1 225 42.265 16 31.8 251 41.065 17 24.3 243 40.711 18 73.5 93 39.856 19 35.8 229 37.372 20 23.7 284 36.913 21 26.6 224 36.724 22 34.7 240 34.384 23 78.8 192 33.245 24 67.9 192 32.682 25 76.3 150 31.869 26 71.5 243 30.474 27 56.5 223 23.229 28 77.4 54 21.080 29 67.2 231 19.973 30 81.5 30 16.441 31 31.3 171 15.275 32 36.3 330 8.838 33 77.2 50 7.758 34 42.2 188 6.300 December 14, 2001 Page 116 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page .X. of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
December 14, 2001 GEO.DCPP.01.21 Rev. 2 Dip Depth(5) of BoringW) ID(2) Dip(3) Direction(4)
Fracture 01-B 1 71.5 215 2 41.6 245 66.291 3 69.0 250 65.902 4 59.6 237 64.885 5 36.5 194 47.241 6 62.1 214 37.695 7 60.8 266 33.099 8 28.5 277 27.706 9 83.0 257 26.796 10 41.5 259 26.506 11 39.4 163 22.992 12 75.6 243 21.277 13 27.8 180 20.117 14 25.6 326 18.984 15 28.7 273 16.330 16 65.8 229 11.573 Page 117 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page M1 of 185Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Depth" 5) of Dip Depth(5) of Boring() ID(') Dip(3) Direction(4)
Fracture BoringM' ID'2) Dip(3) Direction(4)
Fracture 01-D 1 34.1 251 58.192 01-E 1 51.8 210 79.228 2 44.3 192 50.247 2 64.7 208 78.505 3 65.5 265 49.672 3 72.1 210 75.400 4 33.6 191 47.825 4 79.4 281 66.396 5 66.9 278 42.957 5 75.2 253 59.959 6 61.8 275 42.454 6 76.9 215 57.898 7 62.9 254 42.040 7 67.6 229 54.626 8 51.6 108 40.118 8 69.2 220 53.573 9 30.4 282 36.591 9 85.4 232 51.698 10 26.2 303 36.454 10 81.1 22 36.199 11 62.7 266 36.174 11 63.8 267 35.461 12 42.8 204 34.882 12 68.3 278 29.089 13 60.7 77 34.449 13 45.0 236 25.673 14 30.9 328 33.706 14 66.5 2 15.680 15 44.1 299 33.413 15 72.7 342 13.177 16 19.1 346 32.307 16 67.1 203 9.579 17 32.5 304 28.878 18 42.4 332 26.744 19 44.2 297 26.046 20 34.5 200 24.130 21 48.1 183 23.318 22 37.7 229 17.242 23 86.9 95 13.485 24 77.6 241 8.355 25 64.5 273 7.020 GEO.DCPP.01.21 Rev. 2 December 14, 2001 Page 118 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page \ of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Depth'3 of Boring") ID" 2' Dip(3) Direction(4)
Fracture 01-F 2 42.6 224 120.021 3 79.2 45 87.824 4 61.3 197 82.255 5 57.9 213 82.036 6 60.5 215 81.472 7 62.7 228 81.159 8 66.0 231 80.287 9 48.0 238 71.965 10 66.4 218 69.880 11 66.8 190 69.665 12 72.1 194 68.299 13 65.5 223 64.732 14 70.3 17 63.379 15 53.9 178 61.017 16 38.9 317 58.766 17 29.0 200 53.569 18 65.9 2 51.178 19 40.0 182 50.897 20 43.6 194 49.677 21 71.8 230 46.728 22 31.5 185 43.719 23 32.2 188 41.198 24 34.3 193 26.194 25 53.6 211 4.924 Dip Depth 1'3of Boring0) ID(2) Dip(3) Direction(4)
Fracture 01-G 1 78.5 212 71.790 2 61.6 272 70.765 3 46.1 227 65.647 4 68.2 210 63.781 5 70.6 64 61.594 6 69.4 237 50.116 7 67.3 244 49.801 8 67.4 249 49.303 9 78.5 281 31.327 10 58.5 297 26.302 11 31.3 243 14.083 12 72.1 286 11.392 13 63.2 265 7.867 Dip Deptht3 of Boring(')
ID(2' Dip(3) Direction(4)
Fracture 01-H 1 42.3 289 91.717 2 69.0 306 91.210 3 75.9 259 82.788 4 69.8 249 77.589 5 69.6 242 75.574 6 33.7 259 66.793 7 34.5 253 66.625 8 55.2 42 28.355 9 51.0 275 24.063 10 58.4 264 22.203 11 35.1 230 16.238 12 72.3 119 14.676 13 79.4 256 11.530 14 33.9 235 9.324 15 25.5 231 7.332 16 34.4 244 7.207 17 56.2 253 6.520 18 37.5 223 5.819 19 52.8 6 4.867 20 35.3 247 4.466 21 41.4 227 4.297 GEO.DCPP.01.21 Rev. 2 Page 119 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page k 2-_ of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches(continued).
GEO.DCPP.01.21 Rev. 2 Dip of Boring(')
ID(2' Dip(3) Direction(4)
Fracture 01-I 31 67.5 51 78.887 Continued 32 31.3 212 75.704 33 51.4 255 75.464 34 70.5 235 74.900 35 26.5 334 72.003 36 41.9 55 70.583 37 43.4 50 69.833 38 75.5 30 68.897 39 33.2 312 68.243 40 32.0 353 67.022 41 52.8 242 65.306 42 34.7 253 63.965 43 28.7 267 63.620 44 62.8 232 63.491 45 86.3 100 62.249 46 70.3 224 59.336 47 64.7 279 54.240 48 81.7 246 52.161 49 76.3 204 47.551 50 72.4 44 44.221 51 71.1 231 43.762 52 70.2 213 36.817 53 30.7 231 28.024 54 73.2 52 19.099 55 73.2 84 18.667 56 57.2 238 16.602 57 56.3 71 11.194 58 31.1 262 9.688 59 56.5 46 9.493 60 63.3 97 7.176 Page 120 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 0U1of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
GEO.DCPP.01.21 Rev. 2 Dip Type(5) of Trench"'.
ID" 2) Dip(3) Direction(4)
Fracture T- 1 1 56 270 Joint 2 88 347 Joint 3 60 200 Joint 4 84 200 Joint 5 75 10 Joint 6 74 5 Joint 7 84 198 Fault 8 76 78 Joint 9 76 78 Joint 10 78 215 Joint 11 47 202 Joint 12 47 202 Joint 13 47 202 Joint 14 72 355 Fault 15 58 190 Joint 16 82 182 Joint 17 88 190 Joint 18 72 175 Fault 19 82 192 Joint 20 65 185 Joint 21 86 192 Joint 22 86 192 Joint 23 76 210 Fault 24 85 195 Fault 25 85 195 Fault 26 48 175 Joint 27 72 296 Joint 28 83 235 .Joint 29 28 290 Joint 30 80 205 Joint 31 80 200 Joint 32 88 260 Joint Page 121 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 04 of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type(5) of Dip Type(5) of "Trench(')
ID(2) Dip(3) Direction(4)
Fracture Trench() ID(2) Dip(3) Direction(4)
Fracture T-2 1 76 253 Joint T-2 44 80 194 Joint 2 85 187 Joint Continued 45 89 114 Joint 3 71 246 Joint 46 76 211 Joint 4 73 1 Joint 47 85 196 Joint 5 67 251 Joint 48 74 122 Joint 6 86 199 Joint 49 86 289 Joint 7 70 284 Joint 50 84 227 Joint 8 75 24 Joint 51 80 100 Joint 9 71 263 Joint 52 84 118 Joint 10 84 229 Joint 53 51 301 Joint 11 45 297 Joint 54 46 268 Joint 12 86 223 Joint 55 81 119 Joint 13 25 359 Joint 56 86 269 Joint 14 56 277 Joint 57 85 200 Joint 15 70 12 Joint 58 59 261 Joint 16 65 251 Joint 59 86 95 Joint 17 57 15 Joint 60 77 201 Joint 18 64 246 Joint 61 84 278 Joint 19 62 244 Joint 62 86 36 Joint "20 76 290 Joint 63 44 198 Joint 21 70 249 Joint 64 87 75 Joint 22 40 311 Joint 65 65 212 Joint 23 83 350 Joint 66 80 113 Joint 24 89 211 Joint 67 74 222 Joint 25 79 219 Joint 68 84 272 Joint 26 78 65 Joint 69 86 216 Joint 27 69 249 Joint 70 83 256 Joint 28 71 236 Joint 71 70 190 Fault 29 70 273 Joint 72 80 205 Fault 30 84 26 Joint 73 89 3 Joint 31 80 90 Joint 74 72 263 Joint 32 84 215 Joint 75 84 174 Fault 33 64 195 Fault 76 81 32 Joint 34 65 266 Joint 77 90 181 Joint 35 79 204 Joint 78 87 176 Fault 36 75 286 Fault 79 60 2 Joint 37 62 235 Joint 80 64 256 Joint 38 53 323 Joint 81 80 11 Fault 39 83 258 Joint 82 55 199 Joint 40 88 220 Joint 83 61 191 Joint 41 80 223 Joint 84 90 35 Joint 42 86 106 Joint 85 61 286 Joint "43 90 220 Joint 86 55 276 Joint GEO.DCPP.01.21 Rev. 2 Page 122 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page k2kof 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
GEO.DCPP.01.21 Rev. 2 Dip Type"' of Trench"'I ID" 2) Dip(3) Direction(4)
Fracture T-3 1 71 208 Joint 2 69 261 Joint 3 74 226 Fault 4 85 91 Joint 5 76 261 Joint 6 76 320 Joint 7 73 234 Joint 8 76 20 Joint 9 90 190 Joint 10 67 9 Joint 11 30 206 Joint 12 79 309 Joint 13 65 187 Joint 14 64 240 Joint 15 74 208 Fault 16 60 255 Joint 17 85 180 Joint 18 51 248 Fault 19 66 21 Joint 20 61 208 Joint 21 79 218 Joint 22 90 205 Joint 23 62 291 Joint 24 74 201 Joint 25 90 269 Joint Page 123 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page uS of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type"' of Trench(')
ID" 2) Dip(3) Direction(4)
Fracture T-4 1 88 2 85 3 77 4 75 5 88 6 60 7 89 8 58 9 60 10 86 11 42 12 65 13 86 14 88 15 30 16 56 17 86 18 74 19 74 20 50 21 35 22 66 23 42 24 62 25 70 26 82 275 5 258 248 105 11 85 186 5 94 340 100 105 106 185 158 275 220 95 352 332 240 347 250 200 355 GEO.DCPP.01.21 Rev. 2 December 14, 2001 Joint Joint bric of crushed zone Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Fault Page 124 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page Ilk of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type" 4' of Trench" 1' ID(2) Dip(3) Direction(4)
Fracture T-5 1 90 2 90 3 87 4 90 5 50 6 83 7 70 8 90 9 70 10 85 11 70 12 76 13 77 14 64 15 90 16 87 17 57 18 55 19 75 20 50 21 70 22 65 23 83 24 84 25 78 277 307 301 283 217 198 121 201 70 330 70 76 105 291 42 294 131 265 344 254 144 249 146 55 165 GEO.DCPP.01.21 Rev. 2 Page 125 of 181 December 14, 2001 Dip Type") of Trench"' ID" 2' Dip(3) Direction(4)
Fracture T-5 26 63 250 Fault Continued 27 86 252 Joint 28 74 345 Joint 29 25 242 Joint 30 75 264 Joint 31 63 271 Joint 32 78 249 Joint 33 77 209 Joint 34 70 270 Joint 35 86 261 Joint 36 76 204 Joint 37 51 280 Joint 38 70 252 Joint 39 74 18 Joint 40 75 258 Joint 41 90 339 Fault 42 85 340 bric of crushed 43 79 206 Joint 44 78 71 Joint 45 83 185 Joint 46 84 289 Joint 47 57 226 Joint 48 61 243 Joint 49 75 241 Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Fault bric of crushed zone Joint Joint Joint bric of crushed zone Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Calculation 52.27.100.731, Rev. 0, Attachment A, Page I?- of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches(continued).
GEO.DCPP.01.21 Rev. 2 Dip Type&'of Trench"')
IDU 2) Dip(3) Direction(4)
Fracture T-6 1 70 0 Joint 2 40 215 Joint 3 48 10 Joint 4 90 220 Joint 5 78 70 Joint 6 89 82 Joint 7 71 92 Joint 8 82 265 Joint 9 68 25 Fault 10 88 105 Joint 11 82 52 Joint 12 88 95 Joint 13 90 310 Joint 14 62 15 Joint 15 15 240 Joint 16 70 6 Joint 17 88 85 Joint 18 22 225 Joint 19 80 255 Joint 20 84 345 Joint 21 18 230 Joint 22 74 75 Joint 23 72 238 Joint 24 76 4 Joint Dip Typeý-" of Trench"')
1D6" Dip(3) Direction(4)
Fracture T-6 25 86 190 Joint Continued 26 78 70 Joint 27 82 200 Fault 28 89 265 Joint 29 78 255 Joint 30 22 235 Joint 31 89 180 Joint 32 85 270 Joint 33 85 145 Joint 34 82 70 Joint 35 80 255 Joint 36 90 145 Joint 37 86 46 Joint 38 78 292 Joint 39 76 333 Joint 40 80 290 Joint 41 78 185 Joint 42 84 185 Joint 43 74 245 Joint 44 78 260 Joint 45 86 215 Joint 46 76 65 Joint 47 75 250 Joint 48 75 10 Joint Page 126 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page 1.__ of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type" 5) of Trench(')
ID12) Dip(3) Direction(4)
Fracture T-11 1 79 122 Joint 2 63 346 Joint 3 80 317 Joint 4 81 15 Joint 5 65 349 Joint 6 78 41 Joint 7 65 314 Joint 8 70 238 Joint 9 70 1 Joint 10 85 285 Joint 11 84 295 Joint 12 75 198 Joint 13 50 355 Joint 14 55 260 Joint 15 86 180 Joint 16 87 255 Joint 17 85 10 Joint 18 70 281 Joint 19 35 314 Joint 20 90 249 Joint 21 82 264 Joint 22 65 260 Joint 23 85 171 Joint 24 71 208 Joint 25 89 242 Joint 26 90 255 Joint 27 64 0 Joint 28 68 70 Joint 29 72 221 Joint 30 84 61 Joint 31 80 164 Joint 32 76 267 Fault 33 81 66 Joint 34 79 6 Joint 35 79 229 Joint 36 77 193 Joint Dip Type(5) of Trench"' IDj 2 l Dip(3) Direction(4)
Fracture T-12 1 49 274 Joint 2 83 236 Joint 3 79 20 Fault 4 77 180 Joint 5 79 197 Joint 6 85 1 Joint 7 77 231 Joint 8 55 258 Joint 9 64 175 Joint 10 73 226 Joint 11 88 228 Joint 12 45 213 Joint 13 90 25 Joint 14 67 221 Joint 15 60 158 Fault 16 80 350 Fault Dip Type(5) of Trench(')
ID12) Dip(3) Direction(4)
Fracture T-13 1 81 208 Joint 2 90 195 Joint 3 66 248 Joint 4 89 244 Joint 5 87 202 Joint 6 82 248 Joint 7 55 210 Fault 8 43 209 Fault 9 81 340 Fault 10 79 265 Joint 11 23 205 Joint 12 81 85 Joint 13 47 46 Joint 14 61 200 Joint 15 14 200 Joint 16 80 186 Joint 17 69 9 Joint 18 76 256 Joint 19 51 254 Joint 20 82 24 Joint 21 83 195 Joint 22 60 233 Joint 23 86 15 Joint GEO.DCPP.01.21 Rev. 2 Page 127 of 181 December 14, 2001 Calculation 52.27.100.731, Rev. 0, Attachment A, Page tLL0 of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type(5) of Trench(')
ID2) Dip(3) Direction(4)
Fracture Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint December 14, 2001 GEO.DCPP.01.21 Rev. 2 T-14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 87 49 83 74 68 48 90 30 68 86 74 59 52 50 78 71 76 85 87 83 84 86 80 85 90 79 88 90 52 75 90 84 85 80 61 90 11 266 2 195 99 154 226 1 245 183 273 4 184 185 165 264 178 279 299 250 0 279 352 322 2 6 185 270 356 162 13 330 22 266 176 279 Dip Type (5) of Trench") 1D(" Dip(3) Direction(4)
Fracture T-14 37 84 333 Joint Continued 38 85 81 Joint 39 80 28 Joint 40 86 196 Joint 41 81 174 Joint 42 85 115 Joint 43 69 3 Joint 44 81 96 Joint 45 90 220 Joint Dip Type (5) of Trench(')
ID(2) Dip(3) Direction(4)
Fracture T-15 1 77 229 Joint 2 66 209 Joint 3 83 69 Joint 4 85 72 Joint 5 90 66 Joint 6 86 70 Joint 7 90 32 Joint 8 90 64 Joint 9 87 71 Joint 10 85 246 Joint 11 30 140 Joint 12 83 44 Joint 13 69 185 Joint 14 83 248 Joint 15 80 81 Joint 16 62 39 Joint 17 81 238 Joint 18 65 312 Joint 19 60 56 Joint 20 76 255 Joint 21 72 254 Joint 22 78 222 Joint 23 84 25 Joint 24 87 21 Joint 25 90 250 Joint 26 87 240 Joint 27 90 272 Joint 28 87 285 Fault Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Joint Page 128 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page [V of 185~ Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type(5) of Trench(1) ID(2) Dip(3) Direction(4)
Fracture Dip Type(5) of Trench"' ID12) Dip(3) Direction(4)
Fracture T-17 1 70 2 86 3 50 4 85 5 46 6 75 7 68 8 50 9 84 10 66 11 30 12 82 13 80 14 78 15 88 16 82 17 72 18 87 19 78 20 86 21 88 22 56 23 47 24 75 25 58 26 72 27 65 28 85 29 90 30 90 31 84 32 85 33 70 34 84 35 86 36 34 37 64 270 290 190 250 235 285 286 205 235 228 320 90 250 75 270 268 82 280 345 90 266 135 138 65 75 190 205 260 230 250 230 252 345 60 205 325 75 December 14, 2001 GEO.DCPP.01.21 Rev. 2 Page 129 of 181 joint joint joint joint joint joint joint joint shear zone joint joint joint joint joint joint joint joint joint joint joint joint joint joint fault joint joint joint joint joint joint joint joint joint joint joint joint ioint/ shear T-17 38 Continued 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 81 72 10 86 74 68 85 74 90 72 76 58 68 68 60 50 68 65 88 38 74 64 56 69 87 72 86 86 56 72 70 68 78 82 75 86 76 80 75 313 305 15 92 180 190 182 65 170 276 200 220 255 22 210 342 68 302 230 272 356 243 210 68 184 232 282 356 172 355 30 40 15 275 15 joint/ shear joint joint/ shear joint joint joint fault fault fault joint joint joint joint fault joint joint joint fault joint joint fault joint joint joint joint joint joint joint joint joint fault joint/ fault fault joint joint joint joint Calculation 52.27.100.731, Rev. 0, Attachment A, Page 131 of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type'- of Trench"'t ID" 2) Dip(3) Direction(4)
Fracture T-17 75 85 60 joint ,ontinuec 76 88 85 joint 77 45 345 joint 78 41 315 joint 79 90 235 joint 80 56 245 joint 81 65 205 fault 82 65 185 joint 83 60 236 joint 84 69 350 joint 85 38 182 joint 86 74 204 joint 87 64 335 joint 88 64 232 joint 89 66 245 joint 90 77 200 joint 91 82 15 joint 92 63 320 joint 93 82 182 joint 94 64 191 joint 95 87 270 joint 96 88 244 joint 97 27 272 joint 98 12 217 joint 99 74 78 joint 100 74 49 joint 101 90 271 joint 102 4 221 joint 103 88 269 joint 104 21 220 joint 105 74 196 joint 106 89 70 joint 107 88 120 joint 108 88 254 joint 109 88 207 joint 110 68 33 joint 111 82 120 joint 112 11 195 joint 113 81 185 joint 114 84 250 ioint GEO.DCPP.01.21 Rev. 2 December 14, 2001 Page 130 of 181 Calculation 52.27.100.731, Rev. 0, Attachment A, Page t3_-of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Trench(" ID (2' Dip(3) Direction(4)
T-18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 76 47 80 88 70 26 87 73 25 71 30 21 89 39 38 32 84 87 78 80 72 84 84 80 25 87 82 72 76 78 88 79 87 88 82 80 62 82 72 80 88 A ) f Type(5) of Fracture GEO.DCPP.01.21 Rev. 2 December 14, 2001 Page 131 of 181 165 245 240 148 237 235 300 228 230 232 218 225 231 247 230 227 215 210 105 192 98 270 325 268 234 210 275 320 40 245 88 257 100 95 280 250 265 250 273 5 262 joint joint joint joint joint "joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint joint shear zone joint joint joint joint joint shear zone joint joint joint joint joint joint Dip Type(5) of Trench(" ID(2" Dip(3) Direction(4)
Fracture T-18 42 75 5 joint Continued 43 76 298 joint 44 88 46 joint 45 57 250 joint 46 79 250 joint 47 86 215 joint 48 28 250 joint 49 88 279 joint 50 84 240 joint 51 69 292 joint 52 70 205 joint 53 68 285 joint 54 87 210 joint 55 72 287 joint 56 67 257 joint 57 80 205 shear zone 58 38 325 joint 59 78 80 joint 60 76 10 joint 61 80 110 joint 62 83 5 fault 63 88 16 fault 64 60 282 joint Dip Type(5) of Trench ID Dip(3) Direction(4)
Fracture T-19 1 38 319 Fault 2 71 42 Joint 3 85 32 Joint 4 84 225 Joint 5 74 224 Joint 6 74 332 Joint 7 76 22 Joint 8 79 355 Joint 9 90 344 Joint 10 88 224 Joint 11 85 169 Joint 12 68 75 Joint 13 88 162 Joint 14 86 226 Joint 15 86 160 Joint Calculation 52.27.100.731, Rev. 0, Attachment A, Page LL3 of 185 Table 21-6. Selected Fractures (Joints, Faults and Shears) Observed in Borings and Trenches (continued).
Dip Type(5) of Dip Type(5) of Trench(')
ID'2) Dip(3) Direction(4)
Fracture Trench") ID(2) Dip(3) Direction(4)
Fracture T-20 1 63 208 Fault T-21 1 51 324 Joint 2 75 11 Fault 2 85 353 Joint 3 68 242 Joint 3 25 28 Joint 4 53 316 Joint 4 44 42 Joint 5 72 189 Joint 5 56 7 Joint 6 69 264 Joint 6 77 68 Joint 7 83 47 Joint 7 71 4 Joint 8 84 261 Joint 8 40 331 Joint 9 82 29 Joint 9 48 332 Joint 10 77 265 Joint 10 20 344 Joint 12 59 215 Fault 11 80 40 Joint 13 70 270 Joint 12 53 320 Joint 14 70 48 Joint 13 77 188 Joint 15 62 293 Joint 14 83 314 Joint 16 61 220 Joint 15 64 3 Fault 17 80 291 Joint 18 56 286 Joint 19 82 205 Joint 20 74 231 Joint 21 60 351 Fault 22 76 176 Fault 23 68 185 Fault 24 80 10 Joint 25 85 290 Joint lotes: (1) Boring or trench where discontinuities, excluding known bedding, were made. In borings, NORCAL from the televiewer images and reviewed by WLA geologists (DCPP ISFSI SAR Section 2.6 Topical Report Appendix E). In trenches, discontinuities were directly observed and measured by field geologiests (DCPP ISFSI SAR Section 2.6 Topical Report Appendix D). (2) Within each subsurface exploration (boring or trench), a unique number was asigned to each discontinuities were numbered sequentially beginning with the deepest (reverse stratigraphic order). In discontinuities were numbered sequentially from one end of excavation to the other. (3) In borings Dips shown to 0.1 of a degree originated from NORCAL interpretation of televiewer logs Appendix E). In trenches, Dips were measured by field geologists (DCPP ISFSI SAR Section 2.6 Topical Report Appendix D). (4) Dip direction in azimuth degrees.
(5) Depth (in feet) of discontinuity encountered in borings from NORCAL televiewer logs (ISFSI SAR type of discontinuity (fault, joint, or crushed zone) classified in trenches (DCPP ISFSI SAR Topical Report Appendix D).December 14, 2001 GEO.DCPP.01.21 Rev. 2 Page 132 of 181