ML14128A369

Humboldt Bay, Caisson Removal Feasibility Study Hundred Percent Draft Feasibility Report

ML14128A369
Person / Time
Site:	Humboldt Bay
Issue date:	10/01/2012
From:	Kiewit Engineering Co, Pacific Gas & Electric Co
To:	NRC/FSME
References
Download: ML14128A369 (1)

Text

d OKiewit HUMBOLDT BAY POWER PLANT EUREKA, CA CAISSON REMOVAL FEASIBILITY STUDY 100% DRAFT FEASIBILITY REPORT 1 OCTOBER 2012 S~Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Table of Contents List of Abbreviations

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iv 1.0 Executive Sum m ary .................................................................................................................................

1 1.1 Project Description

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1 2.0 Technical Challenges

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2 2.1 Slurry W all Construction

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3 2.2 Soil Stockpile Areas .............................................................................................................................

3 2.3 Below Grade Obstructions

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4 2.4 As-Built Plans .......................................................................................................................................

4 2.5 Lim its of Contam ination ......................................................................................................................

4 3.0 Scope 1 Caisson Rem oval Engineering

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5 3.1 Concept Developm ent ........................................................................................................................

5 4.0 Caisson Excavation System ............................................................................................................

6 4 .1 S lu rry W a ll ...........................................................................................................................................

7 4 .2 S o il N a il W a ll .......................................................................................................................................

8 4.3 Sheet Pile & Ring Beam Shoring .....................................................................................................

8 4.4 Instrum entation ..................................................................................................................................

9 4.5 Excavation System Rem oval .........................................................................................................

10 5.0 Engineering Analysis .............................................................................................................................

10 5.1 Historical Docum ents ........................................................................................................................

10 5.2 Slurry W all Investigation

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11 5 .3 S lu rry W a ll .........................................................................................................................................

1 2 5.4 Dewatering

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13 5 .5 S o il N a il W a ll .....................................................................................................................................

1 3 5.6 Sheet Pile W all ..................................................................................................................................

13 5.7 Settlem ent .........................................................................................................................................

13 5.8 Construction Vibration Analysis ...................................................................................................

17 6 .0 S a fe ty ....................................................................................................................................................

1 8 Page Ii O@Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 6.1 Earthquake and Tsunam i Response ..............................................................................................

18 6.2 Equipm ent Noise ...............................................................................................................................

19 7.0 Slurry W all Construction

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19 7.1 PG& E Site Preparation W ork Prior to Slurry W all Construction

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19 7.2 Slurry W all Contractor W ork .......................................................................................................

20 8.0 Scope 2 -Foundation Pile Rem oval ...................................................................................................

21 9.0 Excavation Plan .....................................................................................................................................

22 9.1 Soil Stockpile Area .............................................................................................................................

22 9.2 Slurry W all Excavation

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23 9.3 Caisson Excavation

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24 9.4 Interm odal Containers

-Soil Disposal .........................................................................................

24 9.5 Concrete Debris ................................................................................................................................

25 9.6 Interm odal Containers

-Concrete Disposal ................................................................................

25 10.0 Logistics of Backfill Plan ......................................................................................................................

26 11.0 Traffic Plan ..........................................................................................................................................

26 12.0 Groundw ater Treatm ent Assessm ent ............................................................................................

26 13.0 Storm W ater ........................................................................................................................................

27 14.0 Risk Analysis & Assessm ent ................................................................................................................

27 15.0 Budgetary Estim ate and W ork Breakdow n Structure

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31 16.0 Schedule ..............................................................................................................................................

32 17.0 References

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32 17.1 Historical Docum ents ......................................................................................................................

32 17.2 Engineering References

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33 APPENDIX A ..................................................................................................................................................

34 APPENDIX B .................................................................................................................................................

60 APPENDIX C ................................................................................................................................................

62 APPENDIX D .................................................................................................................................................

71 Page I ii I(MIKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX E .................................................................................................................................................

75 APPENDIX F .................................................................................................................................................

79 APPENDIX G .................................................................................................................................................

82 APPENDIX H ...............................................................................................................................................

120 APPENDIX I ................................................................................................................................................

131 Page liii CfKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report AISC ACI ALARA ANSI ASME ASTM bgs Bq/m 2 BSL CALTRANS CCC CEQA CFM CFR CLSM COPC cy Cs-137 dBA DCGLs DOT DTSC elev.FHWA FSAR GWTS gpm HASP HBGS HBPP HSC IBC IM RAO IM/RAW ISFSI KG LFO LLMW LLRW List of Abbreviation:

American Institute of Steel Construction American Concrete Institute As Low as Reasonably Achievable American National Standards Institute American Society of Mechanical Engineers American Society for Testing and Materials Below Ground Surface Becquerel per Square Meter Background Screening Level California Department of Transportation California Coastal Commission California Environmental Quality Act Cubic Feet per Minute Code of Federal Regulations Controlled Low Strength Material Constituent of Potential Concern Cubic Yards Cesium -137 A -Weighted Decibel Derived Concentration Guidelines Department of Transportation Department of Toxic Substances Control Elevation Federal Highway Administration Final Safety Analysis Report Groundwater Treatment System Gallons per Minute Health and Safety Plan Humboldt Bay Generating Station Humboldt Bay Power Plant Health and Safety Code International Building Code Interim Measures Removal Action Objective Draft Interim Measures Removal Work Plan Independent Spent Fuel Storage Installation Kilogram Liquid Fuel Oil Low-level Mixed Waste Low Level Radioactive Waste Lmax Maximum Sound Level LRW Liquid Radwaste LSA Low Specific Activity MDA Minimum Detectable Activity mCi/ml Microcuries per Milliliter NEHRP National Earthquake Hazards Reduction Program National Institute of Standards and Technology NRC Nuclear Regulatory Commission NUREG NRC Reports OSHA Occupational Health and Safety Administration PCB Ploy Chlorinated Biphenyl PCM Personal Contamination Monitor PCF Per Cubic Foot PGA Peak Ground Acceleration PG&E Pacific Gas & Electric Company pCi/g Picocuries per Gram PPE Personal Protective Equipment PSF Per Square Foot PSI Per Square Inch QA Quality Assurance QC Quality Control Qualified Storm Water Pollution Prevention Plan Developer RAM Radioactive Material RB Radwaste Building RBL Radionuclide Background Level RCNM Roadway Construction Noise Model RCRA Resource Conservation and Recovery Act REM Roentgen Equivalent Man RFB Reactor Fuel Building RP Radiation Protection SAFSTOR Safe Storage SCO Surface Contaminated Object SFP Spent Fuel Pool PG&E's Humboldt Bay Power Plant Site located at 1000 King Salmon Avenue, Eureka, California SPT Standard Penetration Test SVOC Semivolatile Organic Compound TN Transnuclear, Inc.TPH Total Petroleum Hydrocarbon VOC Volatile Organic Compound Page l iv IKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 1.0 Executive Summary This report summarizes the results of our feasibility study for the Unit 3 caisson removal and Units 1, 2 and 3 foundation piles removal. The outcome of our study indicates that it is feasible to remove the caisson and the foundation piles.We have completed "proof of concept" level analyses and plans for a caisson excavation system, which consists of: 1. a cement bentonite slurry wall to minimize groundwater infiltration;

2. a soil nail wall for support of the upper excavation; and 3. a sheet pile and ring beam shoring system for support of the lower excavation.

In addition, we have completed a subsurface field investigation to confirm the presence of the Unit F clay. Confirming the presence of the Unit F clay was critical to the feasibility of the slurry wall. Structural caisson demolition is proposed to be accomplished from the top.down with an excavator-mounted hydraulic hoe-ram. Plans for the caisson excavation system, the work breakdown structure/budgetary estimate, level-1 schedule, and final grading specification, are contained in Appendices A through D, respectively.

For the foundation pile removal, our review of the pile foundations, experience, and analysis indicate that the piles can be removed. Also, because the piles have been in saturated soils except the first couple feet in some cases, the piles are not anticipated to be deteriorated.

Therefore, we believe that the piles will be extracted intact in one piece.The discussion and documents presented in this report have been used to develop this feasibility study, develop the proposed construction means and methods, and the cost estimate.

Sections within this report also meet PG&E contract deliverable requirements as outlined in the PG&E Contract No.3500929301.

1.1 Project Description This caisson removal feasibility study is divided into two scopes of work: Scope 1 work items include:* Installation of a cement bentonite slurry wall around the decommissioning area to control groundwater inflow;" Pre-trenching the slurry wall alignment to remove known and unknown subsurface obstructions including piles and utilities and contaminated soil;" Excavation around the caisson;" Demolition of the caisson; and," Backfilling the void from the caisson demolition and removal.Page 1 HBPP Caisson Removal Feasibility Study 100% Draft Feasibifity Report Scope 2 work items include:* Demolition of Units 1 and 2 foundation slabs and pile caps;* Removal of foundation piles; and,* Backfilling voids from the demolition and pile removal.The following nine specific deliverables are outlined in the Study Contract Documents for each Scope of Work: 1. A Work Breakdown Structure (WBS)2. Excavation Plan 3. Backfill Plan 4. Traffic Plan 5. Groundwater Treatment Assessment

6. Risk Analysis and Assessment

7. Level-i Schedule 8. Final Site Grading Specification

9. A Budgetary Estimate 2.0 Technical Challenges Technical challenges associated with the caisson demolition and removal includes:* Excavation and demolition below the groundwater table;" A PG&E supplied groundwater treatment system with a maximum capacity of 300 gpm;" Trend of and most current regional seismic activity;" Physical site constraints including the operating power plant and other office structures;

• Obstructions from original construction; and" Annual precipitation over 38 inches per year.The purpose of installing the slurry wall is to minimize and control the volume of discharge generated from dewatering such that discharge can be managed and treated through the on-site groundwater treatment system. Key to assuring performance of the slurry wall is maintaining high quality standards on materials and construction procedures, maintaining integrity of the slurry wall diaphragm between panels, and keying the slurry wall into a low permeability stratum (Unit F clay layer).The purpose of the shoring systems described herein are to allow the excavation and demolition work to be safely performed within a controlled footprint, to minimize the volume of excavated material removed, and to minimize deformation, settlement, and operational impacts to the operating HBGS plant. Components of the earth retaining systems have been designed to resist "static earth forces, seismic forces, and estimated construction loading forces.Page 12 I @Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibifity Report Climactic conditions of the Humboldt site also present challenges to the decommissioning work. The annual rainfall of 38-inches will be accounted for in the planning of soil and debris handling, personnel safety, and site traffic management.

In addition, rainwater management and storage plans will have to accommodate all site water being processed through the 300 gpm site water treatment system.Additional challenges that have been recognized as the project has developed are also discussed within the following sections.2.1 Slurry Wall Construction Mobilization, including set up and commissioning of the slurry wall construction equipment, installation of guide walls, batching plant, and de-sanding plant is estimated to require one month prior to beginning slurry wall production.

After mobilization, the estimated production time for completing the slurry wall is five months, based on the PG&E-defined work schedule of four days per week and 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> per day. The estimated five month construction schedule is based on two machines (a hydro-mill and clam shell) operating to collectively produce 150 square feet of wall per hour. This five month schedule estimate does account for some delays due to inclement weather and routine equipment maintenance but does not include pre-trenching for obstructions or removal/relocation of utilities.

Decommissioning and removal of equipment from the site is anticipated to require approximately three weeks. Therefore, the total estimated time frame for slurry wall construction including mobilization and demobilization is about 7 months. This schedule exceeds the 6 month window currently included in PG&E's Preliminary Decommissioning Schedule dated 27 June 2012.An opportunity to accelerate overall project schedule by approximately 2 months could be realized if the operation adopted a working schedule five days per week 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> per day for production slurry wall construction and one 8-hour day (generally Saturday) for equipment maintenance and work preparation.

On occasion, work days may have to increase to 11 or 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> per day to complete certain phases of an operation that cannot or should not be stopped before the operation is completed.

2.2 Soil Stockpile Areas Currently, we are anticipating that the area east of the discharge canal will be available for stockpiling soils (refer to sheet 12-008-009-4 of the Caisson Removal Plans).The slurry wall construction will produce about 15,000 to 17,000 cubic yards of soil which is anticipated to be "clean" and acceptable for re-use as on-site backfill.

The direction provided by PG&E is that the soil will not be allowed to be temporarily stored in the intake or discharge canals. For this study, the soil will only be able to be used for backfill of the caisson excavation or transported to a Class II landfill.Based on PG&E's CAPSTONE document none of the existing trailers are to be moved until "early 2014".To be able to temporarily stockpile the soils on site for processing, the trailers will need to be removed as shown on sheet #12-08-009-4 of the Caisson Removal Plans. Off-site temporary storage of soil from the slurry wall excavation has been included in the study and cost estimate.

This will be further discussed in Section 9.Page 13 O~Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibilty Report For the caisson excavation, trailer city will be available as a soil stockpile area and we are anticipating having a minimum of approximately 50,000 ft 2 footprint with a maximum stockpile height of 8 feet. The caisson excavation will generate an additional 15,000 cubic yards of soil. The soil will be relatively dry because of the dewatering and should be able to be shipped off-site once it has been characterized.

Management of the caisson soil will need to incorporate the two week waiting period for characterization.

Depending on the final stockpile location, potential for settlement over or adjacent to utilities or slope failure should be evaluated.

After the final location is selected, some additional subsurface investigation to evaluate soil properties such as strength, unit weight, and consolidation may be required.2.3 Below Grade Obstructions A pre-trenching operation is recommended along the slurry wall alignment to identify and remove shallow obstructions, unidentified utilities, and screen for potential shallow radiological and environmental contamination.

The recommended pre-trenching would be performed by open-cut excavation along the entire wall alignment.

Recommended trenching dimensions are 6 feet wide and about 15 feet deep (elev -3ft).All other existing documented utilities intersecting the slurry wall alignment should be removed, relocated, or abandoned as necessary prior to slurry wall installation.

Additional discussion regarding utility removal and remediation work is contained in identified sections of this report.For the soil nail wall construction, structures such as the SAS and Turbine building will *need to be removed and some of the Turbine building foundation piles will have to be removed.2.4 As-Built Plans Horizontal survey control for the caisson has not been included with this feasibility study, therefore, final adjustments to the slurry wall, soil nail wall, and sheet pile/ring beam wall may be required to allow for contaminated soil excavation.

The horizontal survey control of the caisson should be performed before final design of the caisson excavation system is initiated.

2.5 Limits of Contamination A subsurface investigation is planned for the slurry wall alignment which will help delineate potential contamination in that area; however, this investigation will not likely provide sufficient data to identify or delineate the potential contamination immediately adjacent to the caisson. An investigation should be performed to delineate the vertical and horizontal extents of contamination beyond the caisson, after removal of near surface structures such as the turbine building and the SAS. The results of this survey are critical in understanding the total final scope of the excavation system requirements.

Otherwise the caisson removal system could be installed within the limits, precluding the removal of contaminated soil.Page 14 IfOKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report1 Remnval F~nsineerinP 3 0 Scone 1 Caisson Removal Enpineerinp 3.1 Concept Development Early concept development evaluated five potential schemes: 1. Mud jacking the caisson;2. Ground freeze to cut-off groundwater infiltration and provide excavation support;3. Conventional shoring systems with dewatering;

4. Cement bentonite slurry wall to cut-off groundwater infiltration; and 5. An open cut sloped excavation with dewatering.

An interface meeting was held on 17 April 2012 for the stakeholders to comment on concepts, communicate their concerns, restrictions, and limitations.

Based on input from the stakeholders, discussion during the first meeting and review of additional historic documents, the engineering team modified the options as required, and prepared a revised set of concepts.

The result was four concepts were carried forward to evaluate technical challenges, excavation area and potential dewatering effort.The four schemes are presented in Table 1: Table 1 -Caisson Removal System Concept Summary Primary Demo Approach Technical Challenge Dewatering Effort Excavation Scheme Footprint Cement Open excavate top Depth and continuity of Low 200 ft diameter Bentonite portion and utilize shoring Unit F clay Slurry Wall system for bottom portion Ground Open excavate top Brackish water and Low 200 ft diameter Freeze portion may need shoring flowing tidal water system for bottom portion adversely affect ground freeze methods Conventional Dewatering to control Penetrating cemented High 120 ft diameter Shoring groundwater to bottom of layer, groundwater caisson treatment Mud Jack Open excavate top May need to demo the Moderate 200 ft x 200 ft portion and use last 10 feet in-place.dewatering to control May require additional ground water dewatering effort A second interface meeting was held on 1 May 2012; the stakeholders and design team evaluated and ranked the alternative concepts.

Each concept was ranked on a point scale from 1 to 5 (five being the best) with 3 being neutral in 15 different categories including cost, risk, feasibility, and site and environmental impacts. The evaluation process resulted in the selection of the slurry wall concept for removal of the caisson. Table 2 presents the ranking matrix.Page 15 rIOKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Table 2 -Removal System Concept Ranking Matrix CEMENT BENTONITE GROUND CONVENTIONAL MUD SLURRY FREEZE SHORING JACK WALL COST 3 1 3 4 SCHEDULE 4 1 3 4 VOLUME OF SOIL DISPOSAL (COST IMPACT) 3 3 3 3 VOLUME OF WATER DISPOSAL (COST IMPACT) 5 5 1 1 LAND AREA REQUIRED 3 1 5 4 ABILITY TO REMOVE SURROUNDING SOIL 4 4 4 1 (NEW) ITEMS LEFT IN PLACE 3 5 5 3 RISK OF LEAVING PRE-EXISTING ITEMS BEHIND 5 5 5 4 SAFETY (PERSONNEL) 3 3 2 4 CONFIDENCE FACTOR 5 1 2 2 RISK OF SITE IMPACT 5 3 2 2 RISK OF UNKNOWNS AND ASSUMPTIONS 3 1 2 1 RISK OF MIXING AQUIFERS 5 5 5 4 COST OF BACKFILL 3 2 2 1 IMPACT TO ENVIRONMENT/PUBLIC PERCEPTION 4 5 1 4 TOTAL 58 45 45 42 Major contributing factors for selection of the slurry wall with conventional excavation include the following:

support system S 0 S Control and maintenance of dewatering during excavation; Reliability of containment system; and, Reliable performance of conventional excavation support systems.The slurry wall concept and the associated support of excavation systems have been designed to a level of detail sufficient to develop concept-level pricing and construction schedule, and sufficient to develop the deliverables identified in the contract.4.0 Caisson Excavation System For the caisson demolition, an excavation system has been designed to maintain a dewatered excavation with discharge rates that can be adjusted to meet the proposed PG&E groundwater treatment system's maximum treatment rate of 300 gpm for all site dewatering activity, and retain the adjacent soil. The caisson excavation system will consist of three major components:

Page 16 IKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 1. a cement bentonite slurry wall;2. a soil nail wall for support of the upper excavation; and, 3. a sheet pile and ring beam shoring system for support of the lower excavation.

In addition, geotechnical instrumentation to monitor the performance of the system has been incorporated into the plans. The locations, details and suggested monitoring of the instrumentation are presented in the plans. Additional discussion regarding the instrumentation is presented in the identified section of this report that follow.The caisson demolition will be discussed in section 9.0 of this report including methods, sequencing, and production.

4.1 Slurry Wall The cement bentonite slurry is a mixture of Portland cement and bentonite powder (natural clay), water and admixtures.

Other materials may be used such as slag cement, which has a slower curing rate and is generally less expensive than Portland cement. Initially, the slurry is a viscous liquid with a typical unit weight of 65 to 75 pcf. The cured slurry mixture has an unconfined compressive strength of about 20 to 80 psi, depending on the final mix design, and behaves more like a very stiff to hard clay. The net equivalent permeability of the completed slurry wall has been estimated to be 1x10-6 cm/sec; however the cured slurry material itself will have a lower permeability.

The wall alignment is excavated with a hydro-mill and clam shell in alternating primary and secondary panels; both of which are about 30 inches wide. The hydro-mill excavates the primary panels and the clam shell excavates the secondary panels which overlap the primary panels about one foot on each side. The panels will be excavated to and penetrate or "key" into the low permeable Unit F clay stratum at an approximate average depth of 170 feet below grade (elev. -160 ft). A graphic of the panel excavation is presented on sheet 12-008-00-9 of the Caisson Removal plans. Discussion regarding the subsurface investigation is contained Section 5.2.The hydro-mill is equipped with a monitoring system that provides real time data for the horizontal and vertical alignment.

The hydro-mill is "steerable" so that when deviations occur the hydro-mill alignment can be corrected.

The clamshell is also equipped with monitoring devices for alignment control. The clamshell follows the path of least resistance where it follows the softer fresh slurry (i.e. viscous) as opposed to the surrounding soil. Because the clamshell is excavating in the softer fresh slurry, essentially a continuous wall is constructed without any seams. Inherently there would be a "seam" between the first and last panels. The key to insuring for the excavation of adjacent panels in fresh slurry is the mix design and timing.The completed slurry wall will essentially create a low permeable "bathtub" for the caisson demolition and other Unit 3 decommissioning activities.

Because the slurry wall prevents horizontal groundwater movement, the volume of water to be pumped and treated is the groundwater contained in the slurry wall, storm water, and minor infiltration.

Page 17 MKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report The slurry wall is not structurally reinforced, therefore excavations made adjacent to the wall should be supported as if the excavation was made in soil. Hence large deep excavations like that for the caisson removal would be required to be sloped or support of excavation systems would need to be implemented.

Due to the physical site constraints, equipment surcharges and the seismic design requirements, the upper 40 feet of the caisson excavation (elev. +12 ft to elev. -30 ft) cannot be sloped and meet the site requirements.

A soil nail wall was selected to reinforce the soil to create slopes that can stay within the project constraints, resist the seismic forces, and support construction equipment.

4.2 Soil Nail Wall Soil nail wall construction would consist of installing 25 foot long by 1.5 inch diameter high strength steel bars on a grid pattern at approximate 4 foot by 4 foot spacing. The steel bars are inserted into the face of the slope at about 15 degrees from horizontal.

There are several possible installation methods;however, the final product is a steel bar encompassed in a 6 to 8 inch diameter grouted 25 foot long hole. The slope or "face" of the wall will be covered with a reinforced shotcrete facing after each level of nails are installed.

The final wall face will be battered about 10 degrees from vertical.

The shotcrete facing will resist soil forces and prevent erosion that would occur during rain on an exposed soil slope and the wall will minimize the volume of soil to excavate, characterize, stockpile, backfill and/or potentially dispose.The soil nail wall will be constructed around the entire perimeter of the caisson. The top of the wall will range from elev. +12 ft around the north, east, and west sides (based on Plant north) of the caisson to elev. +0 ft along the turbine building foundation.

The toe of the soil nail wall will be at elev. -30 ft. The toe of the wall will be offset about 20 to 25 feet from the outside edge of the circular part of the caisson.This will provide a 10 foot bench between the toe of the soil nail wall and the face of the sheet pile and ring beam shoring system. The 10 foot bench will provide an access and egress point for workers during the caisson excavation and demolition work.The designed soil nail wall has a 10 degree battered face which will reduce the overall lateral movement.As the excavation proceeds and the soil nail wall is constructed, the inclinometers will be monitored for lateral deflection (further discussed in section 4.4). If the observed lateral deflection data is predicting greater movement than desired the remaining nails can be post-tensioned to reduce the amount of movement required to mobilize the resistance.

4.3 Sheet Pile & Ring Beam Shoring A primary reason for beginning the shoring system at elev. -30 ft was so that the cemented sand and silt layer between elev.-32 ft and elev. -37 ft can be pre-trenched without specialty equipment from this elevation; allowing for successful installation of the sheet piles. The subsurface data presented in the historical documents showed refusal type blow counts in this stratum. During the recent geotechnical investigation refusal type blow counts were encountered in the granular deposits throughout the depths explored.

Therefore, jetting in conjunction with vibratory hammer pile driving will be used for installation of the caisson sheet piles. In addition, a template at the surface would need to be Page 18 0 Ki lewi t HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report constructed so that the correct circular pattern is constructed and the last set of sheet piles connects to close the circle.The sheet piles would be installed to elev. -91 ft which would allow for excavation of the entire area below the caisson to elev. -81 ft, about 7 feet below the bottom of the caisson tremie slab. If deeper excavation was required to remove contaminated soil, the excavation could be performed in discrete areas and then backfilled prior to excavating another discrete area. An alternate would be to install additional sheet piles around the area of contaminated soil.The ring beams would be installed along the depth of the excavation at 10 ft spacing for five ring beams and at 12.5 ft spacing for four ring beams. The size of the ring beams would in-part be dependent on the number of ring beams used. The ring beams would either be cast-in-place concrete or steel beams.The concrete ring beams range in size from 34 inch square beams to 44 inch square beams depending on the location and number of beams constructed.

Details regarding the ring beams and steel alternate sections are presented on sheet 12-008-009-16 of the Caisson Removal plans.4.4 Instrumentation A geotechnical instrumentation program has been developed for the purpose of monitoring groundwater levels inside and outside of the excavation, and lateraland vertical ground deformation.

Groundwater levels will be monitored using piezometers, with monitoring points, between the caisson walls and the slurry wall, and outside of the slurry wall. The difference in piezometric water level inside and outside of the slurry wall will demonstrate the effectiveness or quality of the slurry wall installation.

The piezometers would also be used to evaluate the integrity of the slurry wall in the event that an earthquake occurs during the period of construction.

For the purpose of collecting real-time piezometric data during a seismic event, automated piezometers should be used.The inclinometers serve to measure lateral movement in the ground surrounding the excavation.

Inclinometers would be placed inside and outside the slurry wall, similar to the piezometers, to monitor the movement inside and outside the slurry wall and near the HBGS operating plant. The instrumentation could be manual or automated readout; however, for the inclinometers manual reading would be most suitable considering the length of the inclinometer casing that would be monitored.

In-place inclinometers with automated readings are best suited when specific zones or soil layers are to be monitored.

Similar to the piezometers, the inclinometers could also help evaluate the location of damage to the slurry wall after a seismic event. This could be observed by excessive deflection or the inclinometer probe would not be able to penetrate the full inclinometer casing depth.In addition to the piezometers and inclinometers, optical survey points would be installed on structures that are considered sensitive to settlement.

The points would be set prior to the slurry wall installation and monitored throughout the project. Additional survey points could be installed on the soil nail wall and sheet pile wall to monitor vertical and horizontal movement.

Discussion about the potential for settlement and lateral movement is discussed in section 5.7.Page 19 i 0@Ki ewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 4.5 Excavation System Removal The caisson excavation system will be removed to the extent feasible, logical, and economical.

The sheet pile and ring beam system will be completely removed. The concrete ring beams will be demolished and disposed of as the excavation is backfilled.

Once the backfill has reached approximately elev. -30 ft the sheet piles will be extracted and salvaged either for re-use or recycled depending on potential ground contamination.

This would be typical practice for temporary support systems.Soil nail walls are not typically removed, and are generally left in place and backfilled.

The shotcrete facing could be removed if it is determined to be an obstruction, but the nails would be typically left in place. If it is determined that the nail elements need to be removed, additional steps would be required to assure stability of the excavation and to fill voids left by the nails. The cost for removing soil nails has not been incorporated in the cost estimate.Similar to soil nail walls, slurry walls are not anticipated to be removed. In order to equalize groundwater pressure inside and outside of the excavation post construction, a series of trenches would be excavated through the slurry wall, thereby breaching the wall to elev. +0 ft. Five trenches, at approximately 100 foot spacing around the slurry wall perimeter would be excavated and backfilled with permeable fill. Additionally, the slurry wall guide walls will be removed.Demolition and handling cost to the waste management facility for concrete ring beams, shotcrete facing and guide walls are included in the cost estimate.

All disposal fees are by PG&E.5.0 Engineering Analysis 5.1 Historical Documents The analyses performed to develop this feasibility study were based on historical studies, reports and design plans available in PG&E files. Also, a subcontracted surveying company field-verified the proposed slurry wall alignment to help identify potential obstructions.

As this conceptual plan for Caisson removal developed, an additional geotechnical field investigation was determined necessary to verify the depth and continuity of the continuous clay layer (Unit F). The details of the investigation are discussed in section 5.2. A list of the documents referenced and reviewed and initially relied upon for this study is contained in the Reference section of this report. Several key documents reviewed and relied upon for this study are:* "Evaluation of the Potential for Resolving the Geologic and Seismic Issues at the Humboldt Bay Power Plant Unit No.3", by Woodward Clyde, November 1980.* "Hydrogeologic Assessment of Unit 3 Area", Humboldt Bay Power Plant, by SHN, March 2010.* "Humboldt Bay Independent Spent Fuel Storage facility -Final Safety Analysis Report Update", by PG&E, November 2011.The Woodward Clyde report provided evidence of the presence and continuity of the Unit F clay at a depth of about 170 feet below grade, about 50 feet thick and was described as the regional aquitard.Page 110 O@Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report The presence of the Unit F clay in the vicinity of the plant site was primarily presented in Appendix C, specifically Plates C-2, C-6 through C-8, C-17, C-36a and C-36b, and was discussed within the text of that report. Appendix E presented strength data in the form of SPT N values for several of the borings in the vicinity of the Unit 3 caisson.The SHN report provided a summary of the historical reports, the geological profile and the site hydrogeology.

Additionally, this document provided the permeability parameters used to develop this feasibility evaluation.

The permeability of the aquifers, based on field data, was presented and summarized in the SHN report. It also provided field test data that indicates the upper brackish aquifer and the lower fresh water aquifer are not separated by an impermeable layer, referred to as the second Bay Clay. Rather, there is a gradual transition between the two aquifers.

Therefore, the second bay clay is not continuous in the area of the Unit 3 caisson, according to SHN's report. This is presented on Figures 4 and 5 in SHN's report.The ISFSI FSAR report was reviewed to understand the site specific seismic parameters, primarily the design ground accelerations for different time and return periods. The final recommended seismic design requirements were provided by PG&E and are based on the 100 year return period seismic event.Peak ground acceleration (PGA) of 0.5g was recommended with an equivalent short period (0.2 sec)acceleration of 1.36g. Electronic communication from PG&E directing the seismic design criteria are attached in Appendix E.5.2 Slurry Wall Investigation A geotechnical, radiological, and environmental subsurface investigation has been performed.

The investigation consisted of four deep soil borings which were advanced a minimum of 15 feet into the Unit F clay layer and 16 shallow geoprobe borings. In general, the borings were performed along the alignment of the slurry wall where accessible.

A summary report including logs of the borings and geoprobes, a location plan, and the results of the geotechnical, radiological, and environmental laboratory testing will be provided after the laboratory testing is completed.

Currently, copies of the four deep soil boring logs are attached in Appendix G.Three of the four deep borings were performed within about 15 feet of the wall alignment; however, boring KB-2 was performed about 70 feet beyond the wall alignment due to other conflicting decommissioning activities at the site. Continuous core samples were collected in each of the borings and SPT sampling was performed at 5 foot intervals in the first 90 feet of each boring and at 10 to 20 foot intervals thereafter.

Representative samples of the collected soil from the ground surface to the Unit F clay were placed in labeled plastic and core boxes. All of the recovered Unit F clay samples were placed in plastic bags and core boxes except the portions used for testing. The samples recovered during the investigation are stored at SHN's office in Eureka, CA.The data collected during the investigation confirmed the presence and continuity of the Unit F clay layer at depths ranging from 160 to 181 feet below grade. The radiological testing performed by PG&E did not indicate the presence of contamination in any of the four borings. Geotechnical laboratory testing will include strength testing, Atterberg Limits, and grain size analysis.

The environmental Page I11

!*f OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report laboratory testing program was determined by PG&E personnel.

The laboratory data will be tabulated in the report, in addition to the original lab reports.The initial geoprobe program consisted of 22 borings at depths ranging from 20 to 45 feet. Three of geoprobes were not performed because they were adjacent to the recent deep borings and an additional three borings could not be cleared due to utilities or obstructions.

The maximum achieved depth of the geoprobes was 28 feet. The locations, depths and laboratory testing requirements for the geoprobes were provided by PG&E radiological and environmental personnel.

5.3 Slurry_ Wall Engineering analyses for slurry trench stability excavation indicates that the standard of industry factors of safety for continuous trenching (1.15) and panel excavations (1.25) can be achieved.

At depths of 160 feet below grade, the in-trench slurry will need a unit weight of about 82 pcf based on the dense soil conditions at depth. The required fresh mixed slurry unit weight will depend on the sand content in the in-trench slurry. For a sand content of 20%, the fresh mixed slurry will need to have a unit weight of 71 pcf. Fluctuation of slurry within the trench has been assumed to be maintained at least 5 feet above the static water level outside of the trench. Final design of the cement bentonite slurry by the contractor will provide the required range of parameters for trench stability.

The design of the slurry wall assumes that a net aggregate equivalent permeability of the constructed slurry wall is equal to or less than 1x10 6 cm/sec. This factor accounts for local leakage to material variability and potential leakage between panels. Using this design basis, an equivalent potential leakage through the wall and into the excavation is estimated to be in the range of 6 gpm per 10 feet of dewatered depth, or less than 60 gpm for the completed excavation.

Groundwater infiltration through the bottom of the Unit F clay layer will be a function of the continuity of the Unit F clay layer and is estimated to be less than 2 gpm.Inflow to the excavation from rainwater has also been considered in the overall dewatering scheme. It is assumed that all rainwater falling within the footprint of the slurry wall will eventually enter the excavation, either by direct runoff or local seepage through the soil within the slurry wall footprint.

Using rainfall records from the Humboldt site, we estimate the net inflow from rainfall will contribute an additional equivalent 30 gpm (1 year-24 hour storm event) to 70 gpm (5 year-24 hour storm event) to the overall dewatering requirements.

In summary, a maximum total pumping capacity of 130 gpm is sufficient to maintain a workable final depth excavation at steady state seepage conditions.

A hydrologic evaluation of the slurry wall relative to the potential impacts to the groundwater and tidal flow was performed by SHN consultants.

SHN has previously reviewed historical documents, conducted several investigations as well as hydrogeological studies for the site. According to SHN's report "the primary impact of the slurry wall will be its alteration of localized groundwater flow." This would occur in the upper and lower aquifers at the site.The expected levels of impact, according to SHN, are negligible to the upper aquifer and minimal localized impact to the lower aquifer. Therefore, it is not expected that the slurry wall will need to be Page 112 i llOKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report breached any deeper than the 10 to 15 feet previously described.

A copy of their evaluation report is included herein as Appendix H.5.4 Dewatering The upper 15 to 20 feet of the site soil is defined as the first Bay Clay layer comprised mostly of silt and clay, therefore the dewatering effort during excavation through these soils is expected to be nominal.However, utility trenches and other areas with granular backfill could hold water requiring increased dewatering efforts. It is anticipated that localized sump pumps will be able to adequately handle the potential for increased flow and the flows will decrease with time as stored water depletes.

In the granular soil below the first Bay Clay, the estimated volume of water per vertical foot of the slurry wall footprint is about 74,000 gallons. To dewater this volume in one day, a pumping rate of about 50 gpm would be required, not including groundwater or storm water infiltration.

Four dewatering wells have been included in the design, each sized to pump up to 100 gpm. If the pumps were operated at the maximum groundwater treatment capacity of 300 gpm, water levels within the slurry wall could be drawn down as much as five feet per day.5.5 Soil Nail Wall The soil nail wall analysis and design was performed in general accordance with the FHWA Soil Nail Wall Technical Manual, FHWAO-IF-03-017, GEC No. 7. The minimum factor of safety against global slope stability failure for seismic (dynamic) conditions was 1.68 and 2.68 for static conditions.

The factor of safety for internal stability of the soil nail wall, (e.g. nail pullout, face rupture) for the design seismic event was 1.70. For the static case, the factor of safety was 2.41. Both the seismic and static cases included surcharge loading from a Manitowoc 2250 crawler crane.5.6 Sheet Pile Wall The sheet pile and ring beam system was analyzed with the SupportlT computer software.

Seismic lateral forces were analyzed in general accordance with the National Earthquake Hazards Reduction Program (NEHRP) Recommended Seismic Provisions for non-yielding walls. The ring beams were sized to resist the greater of the combined static and seismic forces with a factor of safety of 1.25 or the static forces with a factor of safety of 2.0. The ring beams were designed based on ACI 318 and the AISC Steel Construction Manual, 1 3 th edition.5.7 Settlement The excavation for the caisson demolition will result in both lateral and vertical displacement of the soil surrounding the excavation.

The settlement (vertical displacement) and lateral displacement has been estimated with empirical models based on observed data presented by Clough and O'Rourke in their"Construction Induced Movements of In-Situ Walls" and checked against numerical models utilizing two-dimensional finite element modeling with the computer software PLAXIS. The PLAXIS model is considered preliminary since the input soil parameters were estimated from material index properties and engineering judgment without specific laboratory data.Page 113 O@Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report The historical data compiled by Clough and O'Rourke suggest that a triangular distribution of the settlement profile can be assumed. This distribution assumes the maximum settlement takes place at the face of the excavation and goes to zero at a distance of approximately two times the excavation depth, or in our case 180 feet. This method predicts the settlement averages 0.15% of the excavation height and the lateral movement averages 0.2% of the excavation height. With this empirical method, the estimated settlement is 1.6 inches and the lateral displacement is 2 inches at the face of the excavation due to caisson removal.The finite element model includes the various soil types, excavation stages, dewatering conditions, slurry wall, soil nail wall, and sheet pile and ring beam system. The model was analyzed in stages similar to the actual construction and excavation process. For example, one stage would be excavation for the upper half of the soil nail wall and the following stage would be installation of the soil nails for the upper half of the wall. The results of PLAXIS modeling indicate a maximum settlement of 1.7 inches and 2.5 inches of lateral displacement at the crest of the excavation which we interpret as verification of the empirical estimate.

The finite element model also predicted localized movements of the face of the soil nail wall on the order of 4 inches. The results of the finite element model are shown on Figures 1 and 2, respectively.

Based on the results of our analysis and previous experience, we estimate the settlement to be approximately 2 inches at the face of the excavation and nil at the operating power plant. Figure 3 graphically presents the approximate settlement range versus distance from the caisson excavation.

In addition, the HBGS is supported by pile foundations, according to PG&E personnel.

Therefore settlement of the HBGS structures is not anticipated.

Page 114 1OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report~in Plads Output Vesion 2010.0.0.5880 I 200.00 160.00 120.00 80.00 -4 40.00 "-j 40.00o-40.00 OM 40.00 $0.00 120.00 160.10 2001.00 240.00 200.00 175.00 150.00'2600 100.00 75.00 50.00 25.00 000-2500-50.00-75.00-100M00-12500-150.00-175.00-200.00-225.00 Y Total displacements u y Maximum value = 0.1888 ft (Element 88 at Node 44)Minimum value = -0.2116ft (Element 349 aW Node 225) =2.5 in PLAXIS kt 0 1 2 I _ __ i 9-13-2012 9/19/2012 51 IKiewit Corporation Figure 1 -PLAXIS Model Maximum Settlement Page 115 eOKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Plaxis Output VMsio 201 0.0.0.%880

-40.00 0.00 4000 80.00 120.00 160.00 200.00 240.00 2000 100.00-120.00 80.00-40.00-0.00 -~2.5 in L3T4..20.00 0.00-20.00 40.00-60.00-80.00-100.00-120.00-140.00-180.00-180.00-200.00 U20.00-240.00-2M000-29D.00-20000-320.00-40.00 Y Total displacements ux Maximum value = 0.000 It (Element 7 at Node 10)Minimum value = -0.3427 ft (Element 349 at Node 2. 7)i= in-3212 9/19/2012 PLAXIS 3_9-13-2012 51 Kiewit Corporation Figure 2 -PLAXIS Model Maximum Lateral Displacement Page 116 OGKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report NO SETTLEMENT OPERATING POWER PLANT Figure 3 -Estimated Area of Settlement 5.8 Construction Vibration Analysis The on-site gas line that feeds the operating power plant was identified as a utility of concern by PG&E personnel.

Currently, no data regarding the construction of the line (e.g. material type, size, or bedding)or the specific as-built location and depth have been provided.

The potential for damage to utilities is relative to their flexibility, e.g. steel pipelines are more flexible than concrete and therefore can withstand higher particle velocities without damage. For the purposes of this study, we have calculated estimates of the peak particle velocity from the pile extraction activity.

Because the location material type and size of the gas line was not provided, peak particle velocities were calculated at distances from the vibration source of 25 feet, 50 feet and 100 feet. It is anticipated that the gas line is at least 25 feet away from the existing piles that will be removed.Page 117 Ia OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Based on the upper 15 to 20 feet of soil being firm to stiff clay and the gas line located within the clay layer, peak particle velocities are estimated to be about 0.4 in/sec at a distance of 25 feet from the source and 0.15 in/sec at a distance of 50 feet. At a distance of 100 feet the peak particle velocity is about 0.05 in/sec. Figure 4 below, by Wiss (1981), presents peak particle velocities for a range of construction equipment versus the distance from the source. Also presented on the figure, is the damage threshold for commercial construction and the results of our calculations (in red).1000 Typical Earth Vibrations due to Construction (after Wis, 1981)100 1. .lb --I--1Ebedded Dynamite E --1/2 Ton Ball, 10ft Swing E Diesel Pile Driver, 36,000 ft-lb'10- ... Vibratory Pile Drver o -x -Pavement Breaker, 6 ft Drop> C-a- 2 Ton Drop Batl, 40 ft Drop 00 ---- Caisson Drilling & Large Dozer-X- Trucks... 0 Dacamage Trese eiet UX-X -Cranie Idling 0.01 Damage. ... -Threshold

-Commercial 10 100 1000 Distance from Source, m Figure 4 -Construction Vibrations 6.0 Safety 6.1 Earthquake and Tsunami Response The proposed soil nail wall and sheet pile wall have been designed to resist the required seismic design parameters and typical temporary design factors of safety. Details regarding the analysis and resultant factor of safety are discussed in section 5.0.In addition to designing safe soil restraining systems, safe worker access and egress to the excavation has been considered.

There is a minimum 10 foot bench designed around the entire caisson between the bottom of the soil nail wall and the top of the sheet pile wall. This 10 foot bench along with the battered soil nail wall face will allow for easy access and egress with ladders. The ladders can be supported/tied into the soil nails and constructed as the excavation proceeds.

As the excavation proceeds inside the sheet pile wall, fixed ladders with cages would be necessary for access and egress.Page 118 CKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report As the excavation proceeds and access and egress become challenging, earthquake/tsunami evacuation drills would be performed to assess the adequacy of the access and egress procedures as well as the time for all workers to evacuate the excavation and get to the appropriate muster point (the high point of the site near the ISFSI). The drills would be performed to meet the seven minute tsunami run-up warning.6.2 Equipment Noise Table 3 is based on the Federal Highway Administration's (FHWA) roadway construction noise model (RCNM). The RCNM is based on noise calculations and noise monitoring from the Central Artery Tunnel ("Big Dig") project in Boston, Massachusetts.

The maximum sound level (Lmax) presented are based on the A-weighted method in accordance with OSHA 29 CFR standard 1910.95.Table 3 -Equipment Noise Emissions Equipment Acoustical Use Lmax at 50 ft Measured Lmax Data Points Factor (%) (dBA) at 50 ft (dBA)Clam Shovel 20 93 87 4 Excavator 40 85 81 170 Mounted Impact 20 90 90 212 Hammer (Hoe Ram)Slurry Plant 100 78 78 1 Slurry Trenching 50 82 80 75 Machine Vibratory Pile Driver 20 95 101 44 7.0 Slurry Wall Construction This section addresses the work to be performed by the slurry wall contractor, and work that will be required to be performed before the slurry wall construction begins by PG&E.7.1 PG&E Site Preparation Work Prior to Slurry Wall Construction The following is to be performed by PG&E prior to the start of the slurry wall congtruction schedule: 1. Review and approval of the following contractor submittals:

• Detailed Slurry Wall Design Plan* Slurry Wall Mix Design* Slurry Wall Stability Analysis* Quality Assurance/Quality Control Plan* Instrumentation and Monitoring Plan Page 119 IKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 2. The superstructure of the SAS, turbine building, and tank structures will need to be removed.Based on the current decommissioning schedule, these activities are planned to occur before the slurry wall construction.

3. Based on the plans, the SAS and turbine building have finish floor slabs lower than EL+12. The area along the slurry wall alignment will need to be level, so voids left by demolition of the superstructures will need to be filled. This should be incorporated into the slurry wall contract work, which would place the responsibility on the contractor for their equipment support.4. Obtain required permits and approved RAW or license termination plan 7.2 Slurry Wall Contractor Work The following defines the work to be performed by the slurry wall contractor:

1. Complete additional borings, if necessary, to confirm location and characterization of Unit F clay aquitard.

This information to be utilized for final slurry wall design.2. Develop and submit for PG&E review:* Detailed Slurry Wall Design Plan* Slurry Wall Mix Design* Slurry Wall Stability Analysis* Quality Assurance/Quality Control Plan* Instrumentation and monitoring plan preparation and submittal for review and approval by PG&E 3. Mobilization would include preparation of the subgrade to support construction loads including voids left from superstructure demolition of the SAS, Hot Shop and Turbine building; setup and calibration of the slurry plant; setup of de-sanding plant; and mobilization of slurry wall construction equipment to the site.4. Pre-trench the slurry wall alignment.

This includes the removal of all non-essential and cold and dark underground utilities within 10 feet of the slurry and removal or relocation of overhead electric lines within 20 feet of the proposed slurry wall alignment, removal of contaminated soils, and backfilling the excavation with CLSM. Open utility conduits, pipe, tunnels, etc shall be capped and/or filled with CLSM. At a minimum, the pre-trenching shall be 6 feet wide by 15 feet deep. The final depth of the trench will be dependent on the extent of the contamination.

The removal of contaminated soils beyond the 6 ft wide trench is not considered part of this scope of work unless it is expected to contaminate the slurry wall.5. Protect, temporarily support and/or relocate essential utilities servicing Unit 3 such as electric, water, main plant exhaust system and communication.

6. Removal of foundation-piles and concrete slabs from Unit 2 that are along the slurry wall alignment.

7. Install, read, and maintain piezometers, inclinometers, and/or other instrumentation required by instrumentation and monitoring plan.8. Construct the slurry trench guide walls.9. Construct the slurry wall in accordance with approved QA/QC plan.Page 120 OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 10. Verify performance of slurry wall. This would be accomplished by monitoring piezometers at the beginning of dewatering and observing the reaction of the groundwater levels outside of the excavation.

Successful performance of the slurry wall would be groundwater infiltration rates less than 30 gpm for a dewatered elevation of elev. -20 ft. Specific details of the performance testing should be included in the contractor submittals listed under item 2 above. Rainfall measurements will need to be collected to account for the additional infiltration.

11. Demobilization 8.0 Scope 2 -Foundation Pile Removal The timber piles removal is planned to be performed with a vibratory extractor hammer. This method would require about 3 to 5 feet of competent pile for the extractor clamp to grasp the pile. The analysis indicates that an APE 200 vibratory hammer would be able to remove the 30 to 40 ft long timber piles.In the unlikely event that the vibratory hammer is unable to remove the pile, additional excavation would be made around the piles by backhoe.The timber piles installed in Units 1 and 2 have pile cutoff elevations ranging from elev. +3 to elev. +10 and Unit 3 has pile cutoff elevations ranging from about elev. -3 ft to elev. +10 ft. Based on the site hydrogeological studies groundwater levels are generally around elev. +5 ft to elev. +7 ft. This would indicate that the timber piles have been submerged with the exception of the first couple of feet and are not expected to be deteriorated.

Therefore, extraction is expected to be accomplished in a single piece.If the first several feet of the pile are deteriorated, this portion of the pile could be removed and some over excavation would be done to provide the 3 feet of competent pile necessary for the vibratory extractor.

The upper 15 to 20 feet of soil at the site is low permeable silt and clay, hence, over-excavating in these soils is not expected to significantly increase dewatering volumes. Also, the Unit 3 piles will be within the slurry wall, hence deeper excavations will not create a problem with groundwater control. If significant inflow is encountered, sheet piles could be temporarily installed around the excavation to minimize the groundwater flow.The extracted timber piles will be cut into lengths that fit the intermodal units. This would be done inside the Waste Management Facility or the existing Rubb tent so that the sawdust could be easily cleaned up and placed inside the intermodal unit as well. The handling of soil excavated for the timber pile removal will be handled in accordance with the approved RAW. Additional details including quantities, production rate, and stockpile locations are addressed in the following Excavation Plan section of this report.Removal of sheet piles and H piles are not expected to leave significant voids in the groundbecause they are not displacement piles. Timber piles may leave voids in the ground where they penetrate cohesive soils which could be filled with a controlled low strength material (CLSM) like flowable fill or cement Page 121 Of*Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report bentonite grout. Voids from timber piles penetrating saturated granular soils are not expected to remain open.The estimated volume of soil that will be excavated for Units 1 and 2 is 2,150 cubic yards. The slurry wall pre-trenching will be narrow in width and will only overlap portions of the unit 2 pile caps. Therefore, only partial demolition and pile extraction will occur during the initial pre-trenching activity.

The remaining foundation removal and excavation is scheduled to begin in 2017, the same time that caisson backfill is scheduled to start. At this time, soil stockpile area in the trailer city area will be available.

9.0 Excavation Plan Soil testing frequency for characterization of excavated soil is based on the current Interim Measures Removal Action Work Plan (IM/RAW) document which was provided to us by PG&E and approved by the California Department of Toxic Substances Control (DTSC). The IM/RAW document addresses the management of excavated soil including testing requirements and the re-use of excavated soil for backfill.

The current IM/RAW addresses shallow excavations, 3 feet bgs and less as stated on page 12 of the report. We understand from conversations with PG&E personnel that a revised IM/RAW will be prepared for the deeper excavations associated with Units 1, 2, and 3 for submittal and approval by the DTSC. Also, the plan will incorporate the DCGL's for radiological contamination as determined by the N RC.Material flow diagrams for the slurry wall construction and the caisson excavation are attached in Appendix H. Also, Table 6 in Appendix H presents the estimated schedule for excavated soil generated each week, options for the number of intermodals units to support the operation and the volume of soil that would still need to be managed after completion of the excavation.

9.1 Soil Stockpile Area A temporary Stockpile/Laydown area will need to be constructed in the area east of the discharge canal, referred to as "Trailer City". The proposed soil stockpile area is shown on sheet 12-008-009-4.

For slurry wall construction, areas 5 and 5A will be required for stockpiling and processing of soil so that it can be shipped off-site for temporary storage. During the caisson excavation and removal, the same area would be required for segregation of weekly stockpiles until the soil has been characterized and transported off-site for disposal.

If needed, additional area for caisson excavation would be available after the remaining trailers are removed from the trailer city complex.To mitigate the potential of contaminated water/soil from migrating into the existing subgrade at the Trailer City Stockpile area, the Contractor shall provide an asphalt or concrete pad designed to allow free water flow out of the stockpiles to a containment area. Free water from the stockpiles will be pumped to the PG&E water treatment facility.

Regardless of the pad construction, all stockpiles shall be covered when not in use.Page 122

@OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 9.2 Slurry Wall Excavation The slurry wall excavation will consist of two stages, the pre-trenching which includes the removal of underground utilities, contaminated soil, foundation piles and other below grade structures and the installation of the slurry wall. No superstructure demolition or removal is included in this work.Based on meetings with PG&E personnel, all the material (soil and utility materials) from the pre-trenching operation will be placed directly into intermodals.

Foundation materials will be transported to the Waste Management Facility for additional processing.

After the materials are loaded into the intermodals by the contractor, PG&E will be responsible for the on-site/off-site transportation of the intermodals.

The total volume of excavated material will not be determined until after the final site survey (FSS) is completed by PG&E, but based on the minimum recommended pre-trench dimensions of six feet wide by 15 feet deep the total neat volume of material for the slurry wall alignment excavation is about 2,250 cubic yards; however, the estimated volume of excavated soil is about 4,000 cubic yards.We are anticipating that the pre-trenching activity can be completed in about 111 working days, which results in an average of about 36 cubic yards of waste per day. The pre-trenching excavation will fluctuate depending on the different activity work flows described above. It is anticipated that on some days, zero intermodals will be required, and during peak excavation activities as many as 13 intermodals will be required.Based on the current slurry wall alignment and a wall thickness of 2.5 feet, the theoretical volume of soil is approximately 12,000 cubic yards. With anticipated overage beyond the theoretical quantity and swelling of the soils, approximately 17,000 cubic yards of loose soils will need to be handled and stockpiled.

The excavated material is expected to be wet and often fluid in nature during the excavation, loading, and stockpile operations.

Because soil remediation along the slurry wall alignment will be completed before slurry wall construction begins, the excavated soil from the slurry wall is anticipated to be acceptable for re-use as backfill for industrial site use. For this study, we have assumed the excavated material will meet the criteria of the California DTSC for re-use below the groundwater table.Approximately 1,000 cubic yards to 1,500 cubic yards could be stockpiled on a weekly basis. For this study, we have assumed 1,000 cubic yard stockpiles.

In order to handle this quantity of saturated material at a fairly rapid pace, allow some time for the excavated material to drain-out, and maintain a three week on site stockpile storage capacity prior to shipments off-site, the proposed soil stockpile area will be required for laydown and soil processing, if staged/managed correctly.

This stockpile area maximizes the footprint provided by PG&E for contractor use, including the removal area of the phase 1 trailers from trailer city on January 1, 2014.The soil generated from the slurry wall construction will be transported to a temporary off-site storage facility and back to the site to be used as fill by the contractor.

The soil will be transported in dump trucks and shall not contain free water. Upon completion of the slurry wall and off-site transportation of soil, areas 5 and 5A would be available for other site activities until the caisson excavation begins. We understand from PG&E that "clean" soil will not be allowed to be temporarily stockpiled in the canals nor will any of the other planned restoration activities be able to accept/use the soil for backfill.Page 123

@OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 9.3 Caisson Excavation Upon commencement of the caisson excavation and demolition, all materials from the soil stockpile areas shall be removed.The caisson excavation is divided up into two phases. Phase 1 consists of ten 4 foot thick lifts, to allow for the soil nail wall construction, between elev. + 12 ft t and elev. -30 ft. Phase 2 includes five lifts ranging in thickness from 4 feet to 14 feet between elev. -30 ft and elev. -80 ft. Materials excavated from around the caisson will be loaded into trucks and hauled to the temporary stockpile location for testing by PG&E. On average, each lift of excavation within the caisson will generate approximately 1,000 to 1,200 cubic yards of material to be stockpiled at the Trailer City Stockpile area. A lift on average for both Phases 1 and 2 will have durations for excavation of approximately one week, and then have approximately three to five weeks until the next excavation lift begins. For this study, we have used a four week cycle time. This material flow cycle will allow for the two week testing period and one to two weeks to relocate the material to its next destination before the next excavated lift of material (1,000 CY) arrives to the stockpile area.Once the individual stockpile has been characterized, the material within the stockpile can be moved to a larger stockpile with the same characteristics, freeing up additional temporary laydown area for the smaller individual 1,000 cubic yard stockpiles.

The stockpile area can accommodate large quantities of similarly characterized materials.

For this study, we have assumed all soil excavated during the caisson demolition will be contaminated.

Therefore, any temporary 1,000 cubic yard stockpile that may be characterized as acceptable for re-use will need to be promptly removed to another area on site to be utilized as fill material or be disposed of off-site.

This will provide the necessary area for the next 1,000 cubic yards of excavated soil to be stockpiled, tested, and segregated until the laboratory testing is completed.

9.4 Intermodal Containers

-Soil Disposal The stockpile area will be staffed full time with one loader operator/loader and one laborer for support during excavation operations to load soil into the intermodal units. This crew would be full time during the slurry wall excavation and one out of every four weeks during the caisson excavation cycle. During caisson non-excavation weeks, the crew will be part time only to load the required quantity of intermodals to support the off-haul operations.

Soil treatment for water content in the intermodal containers is not included in the budget estimate nor is any re-handling of materials to perform drying operations.

The laydown area shown is fully utilized for stockpiling purposes only and the stockpiles are allowed to self-drain.

For this study, it has been assumed that the two week waiting period for the testing would allow sufficient time for excess water to drain from the soil, allowing the soil to be placed into an intermodal.

Additional site area would be required for treatment or intermodals would need to be relocated by PG&E to other areas on site to provide additional treatment prior to shipment of-site.Based on the caisson excavation production rates presented in Table 6, a minimum of 30 intermodal units will be need to be loaded on average every week to accommodate the construction and maintain a zero stockpile balance. For example, if a zero balance were to be maintained and soil treatment is Page 124

! 0 *Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report needed to remove moisture content, potentially more than 30 containers could be in continual use for this operation.

If the disposal cycle time for a container to leave site and return for reuse is four weeks (one week to load plus one week for treatment, plus a two week roundtrip), potentially 120 intermodals would be required for zero balance. The table also presents different intermodal container quantity options which would reduce the quantity of intermodals in the cycle and allow the stockpile to increase in quantity.

For example, using 25 intermodals per week allows the stockpile to gradually increase in quantity at a manageable rate and would be depleted about 6 weeks after completion of the excavation activities.

With the cycle time described above, 25 intermodals would potentially require 100 intermodals to be in use at one time to support the work.9.5 Concrete Debris Concrete debris will be generated from: " Units 1 and 2 pile caps and slab-on-grade;

• Unit 3 turbine building pile cap(s) and slab-on-grade;

• The refueling building slabs above the caisson; and,* The Unit 3 caisson.Concrete debris will be handled at the Waste Management Facility located south of Count Room Road and west of Donbass Street (based on plant North). The location of the Waste Management Facility is shown on sheet 12-008-009-4 of the Caisson Removal Plans. The concrete demolition will be accomplished with an excavator mounted hydraulic hoe-ram. The in-place demolition will create debris that can be transported to the Waste Management Facility for additional processing such that the debris meets the requirements of the waste disposal site. The contractor will segregate piles of concrete, rebar and other bulk debris for PG&E to load into the intermodal unit. After the intermodal units are filled, PG&E will either move them to an on-site storage location or transport them for disposal.

As concrete debris is generated it will be temporarily stockpiled in the area of Units 1 or 2. The temporary stockpiles will likely be required because other concrete debris will be occupying the waste management facility for processing.

Temporary stockpiles will be covered when not in use.9.6 Intermodal Containers

-Concrete Disposal Concrete removed from the upper section of the caisson will be demolished in 4 foot lifts in conjunction with the soil nail wall construction.

The estimated schedule for demolition of the upper portion of the caisson (elev. +12 ft to elev. -30 ft) is 60 weeks and the anticipated volume of concrete is 3,660 cubic yards. On average 60 cubic yards of concrete debris would be generated each week that would need to be placed into intermodal units; however, this volume could be as high as 100 cubic yards. Therefore, the number of intermodal units required each week to accommodate the volume of debris will be 18 to 30.The estimated schedule for demolition of the lower portion of the caisson and tremie slab is 27 weeks and the anticipated volume of concrete is 2,540 cubic yards. Using an average timeline of 27 weeks will Page 125

!a OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report require average processing of 94 cubic yards. This will require 12 intermodals per week to keep up with debris generation.

10.0 Logistics of Backfill Plan PG&E has not indicated that the soil excavated would need to be backfilled with similar soil, i.e. that backfill does not need to match the existing geologic strata. The final grading specification included with this submittal addresses the specifics of the proposed fill materials including, compaction requirements, gradation, and Atterberg Limits.For the purposes of this estimate, we have assumed that all excavated material from the slurry wall will be used as backfill for the caisson and all material from the caisson excavation will not be acceptable for re-use as backfill.

Backfilling will be done in multiple lifts in accordance with the backfill specification requirements.

Backfill operations will be performed in conjunction with the demolition of the ring beams in the lower portion of the excavation and the shotcrete fascia in the upper portion of the excavation.

Once the caisson has been backfilled to elev. -30 ft, the sheet piles will be removed and backfill will continue to elev. + 12 ft.11.0 Traffic Plan Site plans with traffic routing have been developed for the various operations.

This includes; import and export haul trucks, on-site construction equipment, pedestrian traffic, debris storage areas for testing and re-use, and laydown/office areas. The traffic plans are presented in the plans in Appendix A. The PG&E site roadways, D-Com Ave, RCA Way, etc., will be used only as necessary to transport materials.

The roads will not be used to store materials or as a place to park equipment.

12.0 Groundwater Treatment Assessment The slurry wall will limit groundwater infiltration into the caisson excavation and therefore the dewatering flow rate for the area can be adjusted to meet the groundwater treatment system's maximum influent rate of 300 gpm. Excavations outside the slurry wall are not expected to extend beyond elev. +0 ft or into the more permeable granular soils typically encountered at about elev. -10 ft.Therefore flow rates in these types of excavations are expected to be nominal.Page 126

@Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 13.0 Storm Water Included in the concept plans are anticipated erosion and sediment control details and the locations of these measures around the proposed construction use area. A qualified Storm Water Pollution Prevention Plan Developer (QSD) has reviewed the proposed site use plans and developed the erosion and sediment control plan and details for this feasibility study. The SWPP permit will be obtained by PG&E.14.0 Risk Analysis & Assessment A risk analysis and assessment has been performed for Scope 1 and 2. Tables 4 and 5 below provide the risk, the potential impact(s) to the project, mitigation strategies to reduce and/or prevent the risk, and action plan(s) should the risk item occur.Page 127 ewit.moval Feasibility Study 100% Draft Feasibility Report Table 4 -Scope 1 Risk Analysis & Assessment Matrix Risk Impact Mitigation Strategy / Action Plan e to slurry wall Increase in water Depending on severity of breach action items would be to 1) pump and seismic event infiltration treat more water, 2) Identify breach location and grout to slow infiltration, 3) identify damaged section and replace section of slurry wall e to support of Deformation and/or Shoring system design will include seismic forces and will be engineered tion system/soil failure of the and peer reviewed prior to implementation of the design. The soil nail II from a excavation support wall and SOE are designed based on site specific ground motion studies event system and a 100 yr return period. The same ISFSI seismic parameters have been applied to the soil nail wall and SOE designs.Iwater inflows Increased water Strict QA/QC of slurry wall construction, increase capacity of GWTS, toff area larger treatment grout high permeability areas in wall, emergency procedure in place to:pected requirement increase GWTS to max capacity allowed by design ii overtops Flooding of Training -participate in tsunami drills, provide quick means of egress.tion excavation, risk to worker safety ient of Damage to HBGS Strict procedures will be in place. Design and construct caisson-N excavation removal to minimize settlement of NEWGEN, Monitor NEWGEN during construction to adjust methods prior to damage.iinated Unable to release site Sample soils prior to slurry wall construction.

Continuously sample and)l outside of monitor soils as they are excavated.

Strict soil removal procedures will system be in place. Construct additional shoring system outside of circular sheet pile/soldier pile retaining system.Page 128 ewit.moval Feasibility Study 100% Draft Feasibility Report Risk Impact Mitigation Strategy / Action Plan e to NEWGEN Damage to HBGS Vibration analysis performed during engineering phase prior to)nstruction beginning construction, monitor vibrations during construction phase, ,n and limit equipment based on monitoring.

ial Safety -Injury to people Entry to the excavation will be controlled via barriers per OSHA. Strict falling into the fall protection procedures will be in place.xcavation ckpiling Insufficient area Find alternative storage areas, revise site use plan to add onsite storage.onsite eather/muddy Delays in Prepare for all weather operations, adhere to storm water pollution Dns construction, prevention plan, strict precautionary procedures in place.negative impact on storm water quality:ient on-site Decreased Provide off-site parking and shuttle bus from remote lots, encourage productivity ride share. Relocate engineering, training, and administrative personnel off-site in lab sampling Delay in construction Assure a close and capable lab to evaluate soil samples in expedite form ,osal or reuse activities, overall in case necessary schedule impact Page 129 ewit Smoval Feasibility Study 100% Draft Feasibility Report Table 5 -Scope 2 Risk Analysis & Assessment Matrix Risk Impact Mitigation Strategy / Action Plan!akage Foundation elements Excavate to pile and extract left in ground ii overtops Flooding of Training -participate in tsunami drills, provide quick means of egress tion excavation, risk to worker safety e to NEWGEN Damage to HBGS Evaluate equipment during engineering phase, monitor vibrations during)nstruction construction phase, limit equipment based on monitoring, vibration)n analysis performed prior to beginning construction.

ial Safety -Injury to people Entry to the excavation will be controlled via barriers per OSHA. Strict falling into the fall protection procedures will be in place.xcavation eather/muddy Delays in Prepare for all weather operations, adhere to storm water pollution ons construction, prevention plan, strict precautionary procedures in place negative impact on storm water quality Staff parking Decreased Shuttle bus from remote lots, encourage ride share e)& transport productivity Page 130 i @Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 15.0 Budgetary Estimate and Work Breakdown Structure Our estimate for the caisson feasibility study is $83 million. The budgetary estimate and WBS are attached in Appendix B. The estimate is based on the scope of work outlined in the contract documents, the scope changes, and interaction with PG&E personnel.

The following list provides assumptions made for the purposes of the schedule and estimate.1. 21 March 2013 is the Notice to Proceed (NTP).2. 60 days to submit and approve slurry wall design.3. Pre-trenching of slurry wall alignment will be completed in 111 working days.4. No special work conditions exist for workers during demolition or for excavation in an open air demolition environment.

5. We have allowed time for final site survey to be performed but no additional time for work stoppages or additional excavation due to contamination beyond the planned excavation limits.No contingencies for downtime or work stoppage due to environmental or radiological issues.6. Slurry Plant and de-sanding plant is outside RCA.7. Pumped concrete will be utilized for flowable fill and guide walls.8. All equipment is free released without any replaced components.

9. Hauling of intermodals empty or full will be performed by PG&E.10. Caisson soils will be classified as contaminated and be hauled off-site/disposed of at a PG&E selected dump site. Cost to assist PG&E with loading intermodals is included only. No cost for delivery of intermodals, transporting of intermodals, or disposal fees are included.11. Concrete debris, rebar, sheet piles, timber piles and other bulk demolition debris will be delivered to the Waste Management Facility, processed then loaded into intermodals by PG&E.Handling of all intermodals, transportation of intermodal and disposals fees is not included.12. Off-site temporary soil stockpile will be covered with tarps.13. Pricing based on Kiewit past experience.

14. No time/impact is schedule or priced for RP delays.15. Used $12/1000 Gal to buy water.16. Slurry wall equipment is mobilized/demobilized to/from the East Coast.17. Trailers for this contract will be mobilized and removed from the site by the contractor.

No other trailers will be removed /relocated by the contractor.

18. Use existing parking for craft/staff.

19. All slurry wall soil will be used as backfill for the caisson. The balance of the caisson fill will be imported.20. Pricing assumes that sheet piling will be salvaged at 50% of cost.Page 131 O@Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 21. No demobilization of trailers.22. The instrumentation will be monitored and maintained by the GC selected to perform the slurry wall and caisson excavation and demolition.

23. The dewatering wells will be operated and maintained by the GC selected to perform the slurry wall and caisson excavation and demolition.

24. No demolition of underground pits or vaults.16.0 Schedule The schedule is resource loaded with major pieces of equipment and man-hour loaded utilizing the crew size and production rates of the budgetary estimate.

This man-hour loading will assist PG&E in identifying the average number of workers required to complete the project as well as identify any manpower peaks that are likely to occur throughout the course of the demolition activities.

The schedule is attached in Appendix C.17.0 References 17.1 Historical Documents* "Evaluation of the Potential for Resolving the Geologic and Seismic Issues at the Humboldt Bay Power Plant Unit No.3", by Woodward Clyde, November 1980." "Hydrogeologic Assessment of Unit 3 Area", Humboldt Bay Power Plant, by SHN, March 2010.* "Humboldt Bay Independent Spent Fuel Storage Facility -Final Safety Analysis Report Update", by PG&E, November 2011." "Subsurface investigation Proposed unit No.3, Humboldt Bay Power Plant", by Dames and Moore, July 1959." "Hydrogeologic Assessment Report Humboldt Bay Power Plant", by Woodward Clyde November, 1985.* "Effects of Tides on Groundwater Flow at Humboldt Bay Power Plant", January, 1987." "Humboldt Bay Power Plant Historic Site Assessment", January, 2007.* "Removal of Sub-Structures Position Paper, Humboldt Bay Power Plant", by Enercon, November 2009* "Groundwater Treatment System Conceptual Design, Humboldt Bay Power Plant", by CH2MHiII, November 2011.* "Tidal influence Study of Unit 3 Area, Humboldt Bay Power Plant", by SHN, July 2011.* "Final Draft Interim Measures/Removal Action Work Plan PG&E Humboldt Bay Power Plant", by Arcadis, December 2009 Page 132

@OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report 17.2 Engineering References" FHWA Soil Nail Wall Technical Manual, FHWAO-IF-03-017, GEC No. 7.* AISC Steel Construction Manual, 1 3 th edition." ACI 318* Slurry Walls as Structural Walls. Xanthakos, Petros P. 1979, 2nd Ed.* Construction Vibrations.

Dowding, Charles H. 2000, 1 st Ed." Construction Induced Movements of In-Situ Walls. Clough, Wayne G. and O'Rourke, Thomas D.Page 133

@OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX A CONCEPT PLANS SCOPE 1 & 2 Page 134 HUMBOLDT BAY POWER PLANT EUREKA, CALIFORNIA JOB NUMBER: 12-008-009 CAISSON REMOVAL FEASIBILITY STUDY VICINITY AUAP FEASIBILITY STUDY PREPARED BY: OKiewit KIEWIT ENGINEERING CO.KIEWIT PLAZA OMAHA, NE 66131 DISCLAIMER:

THU INFORAI HRiýN I INTRNDED AS A VROOF OF AND IS DMONSHA IN NATURE.L rr SHALL NOT M CONSTRUED AS CONYMNIMSK ALL NECUGSART IRFORIATIONR EQUIANWO TO PUOFORCHS THlE WOIRKL. CNRO SML -REPO9NSLE "O INDEFMENDENTLTy VALIDATING ALL ELEMUNWTS OF DUIDiN AND PROVIDING ALL NEGHUSRND EiNEERING NECESSAR TO SUIT ITS OWN MISLANS AND MErHODS4 FOR EXECUrTING THE WO1E.

ABV ABOVE ADJ ADJJST/ADJUSTABLE ALT ALTERNATE ALUM ALUMINUM ANCH ANCHOR/ANCHORAGE APPROX APPROXIMATELY S AT AVG AVERAGE BEL BELOW BLDG BUILDING BLK BLOCK BM BEAM BOc BOTTOM OF CONCRETE ROT BOTTOM RON BOTTOM OF WALL BP BASE PLATE/BEGIN POINT BRO BEARING BRKT BRACKET RTWN BETWEEN BVCE BEGIN VERT CURVE ELEV BVCS BEGIN VERT CURVE STATION BW BOTH WAYS Cc CENTER TO CENTER CAJS CAISSON CAP CAPACITY ,_ CENTERLINE CF CUBIC FEET CHAN CHARNEL CJ CONTROL JOINT CLG CEILING CLR CLEAR COG CENTER OF GRAVITY COL COLUMN CONC CONCRETE CONN CONNECTION CONST CONSTRUCTION CONT CONTINUOUS CONTR CONTRACTOR CTR CENTER CU FT CUEIC FOOT CU TD CUBIC YARD B DIAMETER DBL DOUBLE DEG DECREE DEMO DEMOUSH/DEMOUTION DIAG DIAGONAL DN DOWN OWG DRAWING EA EACH EL ELEVATION EMNED EMBEDMENT ENGR ENGINEER EP END POINT EO EQUAL EQUIP EQUIPMENT EVES END VERT CURVE STATION EVCE END VERT CURVE ELEV EW EACH WAY EXIST EXISTING ECP EXPANSION FF FINISH FLOOR FLG FLANGE FND FOUNDATION FT FOOT FTG FOOTING CA GAUGE GALV GALVANIZED GOVT GOVERNMENT GRND GROUND HCL HORIZONTAL CONTROL UNE HORIZ HORIZONTAL 10 INSIDE DIAMETER IE INVERT ELEVATION INV INVERT JOT JOIST JT JOINT K KIP-1OOS KSI KIPS PER SQUARE INCH ANGLE+/- PLUS OR MINUS LOS POUNDS LO LONG LLH LONG LEG HORIZONTAL LLV LONG LEG VERTICAL MAX MAXIMUM MECH MECHANICAL MFR MANUFACTURER MIN MINIMUM MISC MISCEL EOUS NO. NUMBER NTS NOT TO SCALE Oc ON CENTER OO OUTSIDE DIAMETER OPNG OPENINGPLATE PLC PROGRAMMABLE LOGISTICS CONTROL PC PRECAST PERP PERPENDICULAR PI POINT INTERSECTION PLF POUNDS PER LINEAR FOOT PLWD PLYWOIOD PNL PANEL PPM PARTS PER MILLION PSF POUNDS PER SQUARE FOOT PSI POUNDS PER SQUARE INCH PVI POINT OF VERT INTERSECT R RADIUS RCSC RESEARCH COUNCIL ON STRUCTURAL CONNECTIONS REINP REINFORCEMENT REQU REQUIRED REV REISION SCHED SCHEDULE SF SQUARE FOOT SiM SIMILAR SPA SPACING SPECS SPECIFICATION STA STATION STD STANDARD STIFF STIFFENER STl STEEL ST STREET SWL SAFE WORKING LOAD T&B TOP AND BOTTOM TBD TO BE DETERMINED THK THICK / THICKNESS TOG TOP OF CONCRETE TOP TOP OF FOOTING TOP TOP OF PIER TOS TOP OF STEEL TOW TOP OF WALL TYP TYPICAL UNO UNLESS NOTED OTHERWISE VERT VERTICAL W/ WITH W/O WITHOUT WD WOOD DETAIL INDICATOR SHEET I FRO -SECTION OR DETAIL WHICH SECTION (.-,;--/SHEET I WHERE OR DETAIL IS CUT-t'j'i SECTION OR DETAIL CAN RE FOUND SHEET INDEX O. IDRmAlWIN SUBJECT GENERAL I SHEET INDEX 2 GENERAL NOTES 3 GENERAL ARRANGEMENT PLAN 4 SITE USE PLAN STORM, SEWER. WATER. & OIL UTILITIES PLAN , ELECTRIC & TELECOMMUNICATION UTILITIES PLAN SLURRY WALL 6 SLURRY WALL STE USE PLAN 7 SLURRY WALL AUGNMENT PLAN B INSTRUMENTATION

& DEWATERING PLAN 9 TYP ELEVATION

& SECTIONS 10 STORM WATER PREVENTION PLAN STORIM WATlrwR 11 STORM WATER PREVENTION PLAN (BY OTHERS)12 STORM WATER PREVENTION DETAILS (BY OTHERS)SOIL NAIL WALL 13 !SOIL NAIL WALL ELEVATION

& DETAILS 14 ISOIL NAIL WALL DETAILS SHORING AND EQUIPMENT SUPIPORT 15 DEMOLITION EQUIPMENT SUPPORT iN ISHEET PILE & RING BEAM PRINT IS ONE HALF INDICATED GEER AL NOTES 1. ALL DIMENSIONS AND ELEVATIONS ARE IN DECIMAL FEET UNLESS NOTED OTHERWISE 2. CONTRACTOR IS RESPONSIBLE FOR OBTAINING ALL REQUIRED PERMITS ASSOCIATED WITH THE WORK 3. CONTRACTOR SHALL PROVIDE AN OSHA APPROVED FALL PROTECTION SYSTEM WHERE NEEDED 4. BASE TOPOGRAPHIC.

SITE. AND UTILITY PLANS WERE PROVIDED BY PG&E. NORTHING AND EASTING COORDINATES ARE BASED ON NADB83. ELEVATIONS ARE BASED ON NAVD8X.5. CAISSON DIMENSIONS AND SECTIONS ARE BASED ON THE UNIT 3 REACTOR CAISSON VERTICAL SECTIONS -SHEET #55428 REV 8. THE UNIT 3 FUEL PIT AREA PLANS AND SECTIONS ARE BASED ON SHEET f55433 REV 4. UNIT 3 TURBINE BUILDING FOUNDATION PILES LOCATION.

TIP, AND CUTOFF ELEVATIONS ARE BASED ON SHEET #55420 FOUNDATIONS PILUN PLAN 6. CONTRACTOR SHALL SUBMIT PROPOSED CONCRETE DESIGN MIX WITH TEST RESULTS TO THE ENGINEER FOR REVIEW AND APPROVAL 7. REINFORCING STEEL SHALL BE NEW BILLET STEEL CONFORMING TO THE REQUIREMENTS OF ASTT A-61T GR 60 UNLESS NOTED OTHERWISE B. BACKFILL SHALL CONFORM TO THE REOUIREMENTS STATED IN THE CONTRACT SPECIFICATIONS , COORDINATES ARE PROVIDED FOR SURVEY LAYOUT PURPOSES 10. STRUCTURAL STEEL SHALL BE THE FOLLOWING TYPE/ GRADE: A. STRUCTURAL STEEL. EXCEPT AS NOTED, SHALL BE ASTM ASS Fy-SUKSI OR BETTER TI. WELDING A. ALL WELDS SHALL BE WITH 70 KSI ELECTRODE PER AWS DI.1 12. BOLTS A. BOLTS SHALL BE A325 SR BETTER UNLESS NOTED OTHERWISE B. BOLTS SHALL BE USED IN ACCORDANCE WITH RCSC SPECIFICATION FOR STRUCTURAL JOINTS USING ASTVF A325 OR A490 BOLTS C. BOLT HOLES SHALL BE NORMAL SIZE PER RCSC SPECIFICATIONS UNLESS NOTED OTHERWISE 0. LONG THREADED BOLTS SHALL BE ASTM F1554 GR 105 OR BETTER E. J BOLTS SHALL BE ASTIA F1554 GR 36 OR BETTER 13. $J.3RRY WALL S(A HALL BE A CEMENT BENTONITE MIX WITH A MINIMUM AVERAGE PERMEABILITY OF 1X10-6 CM/SEC AND A MINIMUM UNCONFINED COMPRESSIVE STRENGTH OF 20 PSI AT 28 DAYS. CONTRACTOR TO PROVIDE MIX DESIGNS TO PG&E WITH LABORATORY TESTING RESULTS PRIOR TO BEGINNING SLURRY WALL CONSTRUCTTON.

B. SLURRY WALL CONTRACTOR TO PROVIDE SC PLAN FOR SLURRY WALL TO PORE FOR APPROVAL C. SLURRY WALL CONTRACTOR IS RESPONSIBLE FOR PRE-TRENCHING THE SLURRY WALL AUGNMENT TO EL -3 AND INCLUDES C.1. REMOVAL OF ALL NON-ESSENTIAL AND COLD AND DARK UTILITIES WITHIN 10.0' OF THE SLURRY AND REMOVAL OR RELOCATION OF OVERHEAD ELECTRIC LINES WITHIN 20OD' OF THE PROPOSED SLURRY WALL ALIGNMENT C.2. REMOVAL OF CONTAMINATED SOIL AND BACKFILLING THE EXCAVATION WITH CLSM. OPEN UTILITY CONDUITS.

PIPE.TUNNELS, ETC SHALL BE CAPPED AND/OR FILLED WTH CLSM CA3. PROTECT. TEMPORARILY SUPPORT AND/OR RELOCATE ESSENTIAL UTILITIES SERVICING UNIT 3 SUCH AS ELECTRICAL.

WATER, MAIN PLANT EXHAUST SYSTEM AND COMMUNICATION CA,. REMOVAL OF FOUNDATION PILES AND CONCRETE SLABS FROM UNIT 2 THAT ARE ALONG THE SLURRY WALL AUGNMENT 14. DEWATERING A. DEWATERING WELL INSTALLATION AND ABANDONMENT SHALL BE PERFORMED.

AT A MINIMUM. IN ACCORDANCE WITH ALL APPLICABLE STATE AND LOCAL REGULATIONS.

CONTRACTOR TO SUBMIT WELL INSTALLATION LOGS IN ACCORDANCE WITH ALL APPUCABLE STATE AND LOCAL REGULATIONS.

tQC CONTRACTOR TO VERIFY EXISTING/PROPOSED STRUCTURES AND UTILITIES.

NOTIFY THE ENGINEER OF WELLS MOVED MORE THAN S FT C, DEWATERING PUMPS FOR THE DEEP WELLS SHALL BE PLC COMPATIBLE FOR AUTOMATIC SHUTDOWN BY SWIS RECEIVER TANK 0. GENERATORS OR SECONDARY POWER SUPPLY IS REQUIRED IN CASE OF PRIMARY POWER SUPPLY FAILURE. ADDITIONAL PUMPS SHALL BE AVAILABLE IN CASE OF PUMP FAILURE OR REQUIRED MAINTENANCE.

E. ESTIMATED SPECIFIC YIELD FOR THE CEMENT BENTONITE WALL CONTAINED AREA IS 5 MILLION GALLONS THE GWTS HAS A MAXIMUM CAPACITY OF 300 GPM FOR THE ENTIRE SITE WHICH MAY INCLUDE OTHER DEWATERING WORK NOT INCLUDED IN THESE PLANS A G. DEWATERING SYSTEM DESIGN BASED ON A 160 FEET THICIK AQUIFER CONTAINED WITHIN THE CEMENT BENTONITE SLURRY WALL CUTOFF (( ALL PIPING SHALL BE MIN DIAMETER SHOWN ON PLANS. PIPING MATERIAL IS THE CONTRACTOR'S OPTION; HOWEVER. THE PIPING WILL NEED TO BE SERVICEABLE THROUGHOUT THE LIFE OF THE PROJECT AND COMPATIBLE WITH THE DWITS RECEIVER TANS I. PRIOR TO DEWATERING EXCAVATION:

1.1. REFER TO THE INSTRUMENTATION

& MONITORING SECT7ON FOR REOUIREMENTS PRIOR TO BEGINNING DEWATERING 1.2. CEMENT BENTONITE SLURRY WALL SHALL BE COMPLETED 1l.3 PROVIDE BERM. AND SLOPE GROUND AWAY FROM EXCAVATION TO CONTROL SURFACE WATER 1.4. PROVIDE 150 FEET HAND HELD WATER LEVEL INDICATOR (DURHAM GEO SLOPE INDICATOR OR SIMILAR) FOR USE BY OWNERiNSTALL A FLOWMETER TO MONITOR THE FLOW RATE ENTERING THE GWTS RECEIVER TANK I. PROVIDE ROSSUM SAND CONTENT TESTER FOR USE BY ENGINEER.

SAND CONTERT IN DISCHARGE SHALL BE LIMITED TO IOPPM J. PRIOR TO INSTALLATION.

SUBMIT PROPOSED PUMP INFORMATION.

CASING AND SCREEN SPECIFICATIONS.

FLOWMETER MODEL AND FILTER PACK GRADUATION TO ENGINEER FOR ACCEPTANCE K. GROUNDWATER SHALL BE MAINTAINED A MINIMUM OF 5 FEET BELOW THE BOTTOM OF EXCAVATON 15 AVATION AND BACKNFILL CUT SLOPES TO BE OBSERVED ON A DAILY BASIS AND AFTER ANY SIGNIFICANT PRECIPITATION EVENTS FOR SIGNS OF INSTABIUTY B. UTLITY LOCATIONS SHOULD BE VERIFIED PRIOR TO EXCAVATION C. SURFACE DRAINAGE SHOULD BE DIRECTED AWAY FROM DESCENDING SLOPES.0. VEHICLE AND MATERIAL SURCHARGES SHOULD BE KEPT A MINIMUM OF 5 FEET BACK FROM CREST OF SLOPES 16. SOIL NAIL WALL A. MATERIALS AND WORKMANSHIP SHALL BE IN ACCORDANCE WITH ACI 318 AND ACI 506 (MOST RECENT ADDITIONS)

A(/ PERFORM MINIMUM OF ONE CREEP TEST PER -HWA GEOTECHNICAL ENGINEERING CIRCULAR NO.5-SECTION 8.5.5.PRE-PRODUCTION SOIL NAIL LOAD TEST SHALL BE PERFORMED IN THE COHESIVE & GRANULAR SOILS.D. THE SOIL NAILS HAVE BEEN DESIGNED IN ACCORDANCE WITH THE SLD (SERVICE LOAD DESIGN) PROCEDURES CONTAINED IN THE FHWA 'MANUAL F`OR DESIGN AND CONSTRUCTION MONITORING OF SOIL NAIL WALLS, REPORT NO.FHWA-SA-96-069 E. SO(L NAILS: J,, GROUT: TYPE II CEMENT, 4.0DD PSI MIN, 8 INCH MIN1MUM SLUMP. WATER TO CEMENT RATIO (W/C) SHALL NOT EXCEED 0.45 BY WEIGNT FOR GROUT. MINIMUM 3 DAY COMPRESSIVE STRENGTH -1,000 PSI.BARS: Fy-,75 KSI (GRADE 75), CONFORMING TO AS'TM A615.SOIL NAIL ASSEMBLY HARDWARE.

INCLUDING BEARING PLATES. NUTS. AND WASHERS: Fy=36 KSI F 4. LAYOUT OF SOIL NAILS TO BE PERFORMED BY THE CONTRACTOR BASED ON THE DEVELOPED ELEVATIONS AND TYPICAL SECTION. ADAJSTNENTS MAY BE MADE TO ACCOMMODATE FIELD CONDITIONS AS APPROVED BY THE ENGINEER.E.5. TOTAL LENGTH OF TEST SOIL NAILS EQUALS EMBEDMENT LENGTH PLUS EXTRA LENGTH REQUIRED FOR JACKING EQUIPMENT EN6. TESTING OF ALL SOIL NAILS SHALL BE PERFORMED IN ACCORDANCE WITH FHWA SOIL NAI. MANUAL CONTRACTOR IS RESPONSIBLE FOR PROVIDING TEST APPARATUS AND LOADING JACK.E.7. PROOF TESTING SHALL BE PERFORMED ON 5D OF THE NAILS INSTALLED AND VERIFICATION TESTING SHALL BE PERFORMED ON AT LEAST FOUR SACRIFICIAL TEST NAILS F.B. THE MAXIMUM UNSUPPORTED VERTICAL CUT SHALL NOT EXCEED 5 FEET UNLESS APPROVAL IS GIVEN BY THE ENGINEER FOR A TALLER CUT. WALL FACE EXCAVATION SHALL NOT PRECEDE THE INSTALLATION OF NAILS BY MORE THAN 48 HOURS WITHOUT THE PRIOR APPROVAL OF THE ENGINEER.F. TERETE FACING: REINFORCED SHOTCRETE:

A Fy (REBAR) -60 ESI F.3. Fy (WRIN) = 65 KSI FA. F'c = TYPE II CEMENT, 4.000 PSI (28 DAY COMPRESSIVE STRENGTH)FT.S WATER TO CEMENT (W/C) RATIO SHALL NOT EXCEED 0.45 BY WEIGHT FOR SHOTCRETE FA. MINIMUM SHOTCRETE COVER MEASURED FROM THE FACE OF SHOTCRETE TO THE FACE OF ANY REINFORCING BAR OR WIRE SHALL BE 1.5 INCHES. UNLESS OTHERWISE NOTED G. STRUCTURAL OBSERVATION AND SPECIAL INSPECTION G.1. CONTRACTOR SHALL ALLOW FOR UP TO ONE WEEK PER LEVEL OF SOIL NAILS FOR FINAL SITE SURVEY BY PG&E.THIS SHALL BE ACCOMPUSHED SUCH THAT EXPOSED SOIL SLOPES ARE NOT EXPOSED FOR MORE THAN 48 HOURS BEFORE SOIL NAILS ARE INSTALLED.

G.2. PG&E QUALIFIED REPRESENTATIVE SHALL.G.2.1. OBSERVE ALL SOIL NAIL HOLES BEFORE GROUT OR SHOTCRETE IS PLACED G.2.2. INSPECT ALL REINFORCEMENT PRIOR TO PLACEMENT OF SHOTCRETE G.3. THE ENGINEER SHALL OBSERVE AND EVALUATE ALL EXCAVATIONS TO ASSESS WHETHER THE GEOLOGIC CONDITIONS ARE REPRESENTATIVE OF THOSE ASSUMED IN THE DESIGN G.4. THE ENGINEER SHALL PERFORM FULL TIME CONSTRUCTION OBSERVATION OF: G.4.1. SOIL NAIL DRILLING G.4.2. ALL THREAD BAR INSTALLATION G.4.3. GROUTING H. THE ENGINEER SHALL BE NOTIFIES TO OBSERVE ALL SOIL NAIL TESTING 1. THE CONTRACTOR SHALL NOTIFY THE ENGINEER 48 HOURS PRIOR TO REQUIRED OBSERVATION/INSPECTION

17. SHORINGt" CONCRETE SHALL BE P'c -5,000 PSI REINFORCING STEEL SHALL BE ASTM A61TS GR. 60, BAR BENDS PER ACI STANDARDS C. STEEL SHEET PILES SHALL BE ASTT A572. GR. 50 OR BETTER 0. SHEET PILES SHALL PENETRATE A MINIMUM OF 10 FEET BEYOND THE BOTTOM OF EXCAVATION E. EXCAVATION SHALL NOT PROCEED BELOW THE LEVEL OF EACH RING BEAM UNTIL THE RING BEAM HAS REACHED DESIGN COMPRESSIVE STRENGTH F. GENERAL EQUIPMENT F.l. SURCHARGE LOADS: F.2. MANITOWOC 2250 CRAWLER CRANE G. TIMBER 0.I. CRANE MATS SHALL BE 75% HEM-FIR (NORTH) NO. 1 AND 25% HEM-FIR (NORTH) NO. 2 OR BETTER G.2. DECK OVERLAY SHALL BE HEMLOCK NO. 2 OR BETTER G.3. GUARDRAIL CONTINUOUS MEMBERS SHALL BE HEMLOCK NO. 1 H. DO NOT DEMOLISH ANY RING BEAM UNTIL BACKFILL HAS BEEN PLACED UP TO THE BOTTOM LEVEL OF THE RING BEAM 18. INSTRUMENTATION/MONITORING A. INCLINOMETERS SHALL BE INSTALLED PRIOR TO CONSTRUCTION OF THE SLURRY WALL B. PIEZOMETERS SHALL BE LOCATED AT THE COORDINATES PROVIDED.

WITHIN 5 FEET. IF LOCATIONS VARY MORE THAN S FEET. THE ENGINEER SHALL BE NOTIFIED FOR APPROVAL C. PIEZOMETERS AND INCUNOMETERS SHALL BE READ BASE ON THE FOLLOWING SCHEDULE AND THE RESULTS REVIEWED IN THE FIELD BY THE CONTRACTOR.

IN ADDITION, THE RESULTS SHALL BE TRANSMITTED TO THE ENGINEER AND PG&E FOR REVIEW. READING FREQUENCIES BELOW ARE MINIMUMS.

HOWEVER, DURING THE COURSE OF THE JOB THESE MINIMUM FREQUENCIES MAY BE INCREASED OR DECREASED BY CONCURRENCE OF PG&E AND ENGINEER BASED ON THE RESULTS OF PREVIOUS READINGS D. DURING INSTALLATION OF SLURRY WALL -1 PER DAY E. PRIOR TO START OF EXCAVATION DEWATERING

-MIN OF I PER WEEK F. PIEZOMETERS DURING EXCAVATION

-I PER DAY (7 DAYS PER WEEK)G. INCLINOMETERS DURING EXCAVATION AND BACKFILL -2 PER WEEK H. PIEZOMETERS DURING BACRFILL -3 PER WEEK I. INSTRUMENTATION SHALL BE PROTECTED FROM DAMAGE BY CONCRETE BARRIERS, MANHOLES.

OR OTHER APPROVED METHODS PRINT IS ONE HALF INDICATED SCALE L DESIGNED BT NPG , 09-14-12 G.TIF. IOOX DRAP'T SUBMITTAL K.E.M. DRAWN BY ,& i 0 9 --95-2 S I .9 0Z S U B M IT T A L N .P .G-SI S60 SUBMITTAL MPG KIEWIT ENGINEERING CO. CHECKED BY BGALE AS OE DATE AFE,-1 PROJECT TITLE HUMBOLDT BAY POWER PLANT PROJECT LOCATION EUREKA, CA JoB No.T2-OOR-009 PROJECTTASN DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-2-ill I1 DRAWING SUBJECT GENERAL NOTES SHEET N02 OF 16 REV. I DATE IBY I DESCRIPTION CNWD I mffwrr PLAzA OMAHA, HE 6811211 K.E.M.

PLANT LOCATIONS NO. eS PO DNoUumON O. ONO. DUS W ION IUNIT REMOVED 12-5 OECGM SAFETY TRAILER 24-A RMdS 32 RIGGING STORAGE -REMOVED 2 UNIT REAOVED 12-6 ENGINEERING TRAILER 2-B HASKELL SAFETY TRAILER 3 NOT USED 3 UNIT NUMBER 3 12-7 ENGINEERING TRAILER 24-C FINANCE 34 SHEPHERDS SOURCE 4 HOT SHOP 13 COUNT ROOM 24-D NORTH COAST FABRICATIONS 25 UNIT 3 WORK CREW BLDG 5 OFFICES, SHOPS, & WAREHOUSE 13-A FOSSIL DECOMMISSIONING TRAILER 24-E RADWASTE 36 HBGS WORK SHOP B ADMINISTRAT10N ANNEX 13-B RAP OFFICE TRAILER 24-F WARTSILA OFFICE TRAILER B 37 ABOS CONTROL ROOM 7 TRAINING/NETWORK BLDG 14 SOID RADWASTE HANDDUNG BLDG 24-H FRONT OFFICE/ENVtRONMENTAL 38 HBGS MB-BLDG/CONTROL 8 SECURITY BLDG 15 LOW LEVEL RADWASTE BLDG 24-I PROCUREMENT TRAILER 39 HBGS ENGINE HALL 9 FFD TRAILER TB UOUID RADWASTE BLDG 24-J DECOM 6-WIDE OFFICE TRAILER 40 HBGS LV-ROOM 7ASSEMBLY BLDG 1 SAS BLDG 25 OFFICE TRAILER 41 HBGS FIREPUMP HOUSE TO-A INITIAL TRAINING AND BADGING 1 UNIT 3 ACCESS CONTROL 26 PAINT/SANDBLAST BLDG 42 HBOS TEMP OPERATIONS

-REMOVED 1 PRIMARY ALARM STATION (PAS) T9 27 HBPP RREPUMP HOUSE -REMOVED 42 WACH'S TRAILER -REMOVED 12-1 GENERAL ENGINEERING TRAILER 20 RADWASTE OFFICE TRAILER B 28 MOBILE EMERGENCY POWER PLANT I -REMOVED 44 RUBB TENT 12-2 ELECTRICAL ENGINEERING TRAILER 21 HAZARDOUS WASTE STORAGE 29 MOBILE EMERGENCY POWER PLANT 2 -REMOVED 45 FUTURE USE 12-3 MECHANICAL/PIPING ENGINEERING TRAILER 22 NEWGEN/RP B-WIOE OFFICE TRAILER 30 MEPP ISLAND BLDG 12-A CIV1L/STRUCTURAL ENGINEERING TRAILER 23 FUTURE USE 31RELAY BLDG FOOTPATH I ASn'112113-2 "N LC SCAL: 2 -it PRINT IS ONE HALF 2N4ICATED SCALE N.PG. AS NOTED HUMBOLDT BAY POWER PLANT j EUREKA. CA 12-008-O09 t j 9-412OF. .O RAFT ,SUBMITAL FT V I, *.;: K e itI 0.__ " AL00U" PROJECT DRAWING NO.io9-o5-121..I Sl. BOX SUBMITTAL MDAIB CL CAISSON REMOVAL FEASIBILITY STUDY T2-oo9-ooB-3 0,86-15--12 S.2.1. BOXI SUBMITTAL N.P.. KIEWIT ENGINEERING CO CHECKED BTY DATE FDRAWING SUBJECT SWEET NO.RE. DT T DSRPIN CIKS KIEwrr PLZA O HIA N IEt613 RE 7-15--12 RI WT GENERAL ARRANGEMENT PLAN 3OPFI 316 7 2Zvx1 SIn USE SCHEDULE UQEND NO. D IIOI AREA 1 CONSTRUCT1ON STAGING AREA 32.802 2A2A TREATMENT SYSTEM 8.120 II 2B OrTS RECEIVER TANK 383 3A WASTE MANAGEMENT FACIUTY 12.000 38 DEBRIS TESTING AREA 5.250 F4f INTERMODAL CONTAINER STOCKPILE AREA 46.988 5 SOIL STOCKPILE AREA 30.850 5 SOIL STOCKPILE AREA 33.750 6A CONTRACTOR OFICE TRAILER 1.440 6B CONTRACTOR OFFICE TRAILER 2,700 7 HAGS -OPERATING POWER PLANT N/A 8 CAISSON REMOVAL AREA N/A-BUILDINGS

/ STRUCTURES TO REMAIN N/A-INTERMODEL TRUCK ROUTE N/A-CONSTRUCTION EQUIPMENT

& MATERIALS TRUCK ROUTE N/A-STE WALKWAY PAIH N/A-HBGS ACCESS ROUTE N/A SOIL STOCKPILE AREA NOTEE 1. TRAILERS AFLE NEED TO BE MOVED FROM AREA SA BY JANUARY 1. 2014 FOR STOCK PILE CON STRUCTTON 2. A PORTiON OP AREA 54 1811 RE OPEN FOR TRUCA TuRNAROUND PURPOSES SITE USE PLAN S.:C -100 ,.I PRINT IS ONE HALF INDICATED SCALE PROJECT DOLE PROJECT LOCATION JOB NO.00--2 T. 700. DRAFT SUBMITTAL ITEM.P 09-05-12 SJ.H 90RO SUBMITTAL MG DESIGNED BY N.P.OK AA AS NOTED 06 2 HM PROOECT TBALY ER PLANT PROJE LOCATION EUREKA, CA 12-008-009 PROJECT TASK DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-4

& 0 78,-21 .,-6W SUBMIttAL

.wr.G KIEIWIT ENOINEPRINZ COj CNEER DESCRIPTION CA I WPAA CBN.N SS DRAWING SUBJECT SITE USE PLAN A OF 16 REV. I DATE IBYI 1ý/LEGEND STORM DRAIN PRESSURE SEWER-- -- SANITARY SEWR FRESH WATER rI- FRE WATER PIPES 14" PG&E OIL UNE UTIUTY TUNNEL HUMBEOLDT BAY UT/LITIES PLAN SCAL -I7w , -HALF PROJECT LOCATION EUREKA. CA HUMBOLDT BAY POWER PLANT i PROJECT TASK PROJECT TASK CAISSON REMOVAL FEASIBILITY STUDY DRAWING SUBJECT STORM, SEWER, WATER, & OIL UTILITIES PLAN LEGEIND iT4111111CKRI FrHO OVERMEAD POWER-u- UNDERGROUND POWER TELECOMMUNICA1IONS CONDUIT FiBER OPTIC 7 HUMBOLDT BAY ccm UTILITIES PLAN SCAL 1 -00'CA REMOVAL FEASIBILITY STUDY DRAWING SUBJECT ERAWINGCSUBJECT ELECTRIC & TELECOMMUNICATION UTILITIES PLAN LEGEND I V7HYDRONIILL BOUNDARIES 50- FROM I CENTER OF SLURRY WALL ON EITHER SIDE SHEET PILE WALL TO CREATE LEVEL GRADE FOR SLURRY WALL EQUIP. WALL DESIGN TO BE COMPLETED BY CONTRACTOR RCA ACCESS TRACER TO BEREQEDREO A TED TRO a Y PG&E ki PRINT IS ONE HALF INDICATED SCALE SLURRY WALL PLAN NOTE;I' -21r FINAL SLURRY & DESANI1NG PLANT LAYOUT TO SSIE: I" -2 BE DETERMINED BY SLURRY WALL CONTRACTOR PROJECT LOCATION;&09-4-12 0G I YO I I @IDESIGNED BY 9DRAFT SUBMITTAL A t BY 9OX SUBA4ITTAL NPGSJ AS NOTED DTPROJECTTLE PLANTTL HUMBOLDT BAY POWER PROJECT LOCATION EUREKACA JOB NO.T2-008-009 PROJECT TASK DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY 12-0o0-0os-6

.&

&~ 0O6-T-2 S.J.H.~6OZ SUBMITTAL B.P. KIE IT nOIERNO DESCRIPTION OiEDKWTPAA OMNAHA. ME 0101311 I SLURRY WALL SITE USE PLAN SHEET NO.6 OF 1D REV.I DATE I By I CONTROL POINT I IN-m rAWIBA5~l 4 or NO 1NTH N KArllNO 1 2161197.6 59493592 2 11 5949401.B 3 2161185.6 5949455.4 4 2161137.2 5949487.1 5 2161081.5 5949497.6 6 2161023.8 5949507.8 7 21E0975A 5949442.5 a 216101948 594938398 9 2161042.9

__ 5949343.5 10 2161116.5 5949313.6 Ii 2161199.3 5949314.6 A REAS OF AN iCIPATED CONTAMINATION TO BE REMEDIATED PRIOR TO SLURRY WALL CONSTRUCTION.

PROPOSED GEOPROBE INVESTIGATION TO DEUNEATE APPROXIMATE AREAS OF CONTAMINATION IN SEPTEMBER 2012 NOTES: 1. SLURRY WALL CONSTRUCTION TO START NEAR CPul AND PROGRESS IN A COUNTER CLOCKWIME DIRECTION.

FINAL STARTING POINT TO BE COORDINATED PATH PG&E.2. TIMBER PILES UNDER TIJRBINE BUILDING HAVE CUT-OPF ELEVATIONS FROM EL-3.0'TO ELI9.0' ASSUMED PILE CAP THICKNESS IS 2.0'. LENGTH AND DADTH DIMENSIONS OF PILE CAP WERE NOT SHO1 ON THE PROVIDED DESION PLANS AND HAS BEEN ASSUMED TO EXTEND 18*BEYOND THE LIMITS OP THE PILES REFER TO UNITS 1 & 2 FOUNDATION REMOVAL PLANS FOR PILE FOUNDATION DETAILS ALIGNMENT PLAN SCALE: 1 -20 PRINT IS ONES HALF INDICATED SCALE I I I 09-14-12 0.TF.1 10 DRAFT SUBMITTAL 6 59oA SUBMITTAL W I DESIGBED BT ,, @Kiewit I[~K1~!~FVU~hKDRAWN BY N AS NOTED 06-15-12 PROJECT TITLE I HUMBOLDT BAY POWER PLANT PROJEOT LOCATION EUREKA, CA JOB NO.12-0OB--009 PROJECT TASK DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-7 E I V -D5--12 S.J, REV/. DATE BT 6OX SUBMITTAL N.P.0 KIEWIT ENGINEERINGCO DESCRIPTION CHR'D I EWiT PLAZA OMAHA. ME "1131;I ,I DRAWING SUBJECT SLURRY WALL ALIGNMENT PLAN I 0SR"T-"07 OF 16 17ýýINSTRUMENFT LOCATIONS INSTNUMENTATION NOWMIING RAMMING P-1 2161225.0 5949406.0 P-2 2161096.0 5949502.0 P-3 2161010.0 5949376.0 P-4 2161113.0 5949305.0 P-5 2161209.0 5949398,0 P-6 2161092.0 5949480.0 P-7 2161028.0 0949388.0 P-8 2161147.0 5949322.0 1-1 2161131.8 5949329.5 1-2 2161087.0 5949505.0 1-3 2161075.0 5949477.7 1-4 216112860 5949304.0 I-5 216100860 5949548,0 cl DEWA TERING LOCATIONS WIILL NOUYI leNU RAMIN 2161027,0 59494065 2 2161165.5 5949 30.3 3 2161195.4 5949422q7 4 2161080.0 5949483.3 STO I LEGEND I BORING/PIEZOMETER 0 DEWATERING WELL FINAL INSTRUMENT LOCATIONS TO BE DETERMINED IN I FIELD BUT SALL BE WITHIN 10' OF THE SLURRY WALL A UNLESS APPR OVED BY THE ENCINEER 2. PIPING WILL BE BURIED. FINAL DEPTH TO BE DETERMINED BY DEWATERING CONTRACTOR

& APPROVED BY PG-! CONTRACTOR RESPONSIBLE FOR DEWATERING SYSTEM TO RECEIVER TANK. PGOE RESPONSIBLE FOR DEWATERING.

FROM RECEIVER TANK TO DISCHARGE PRINT IS ONE HALF INDICATED SCALE PLAN SCALE: 1-30'06-15121 -I. ::IABO SUBM~ITTAL NA G KIEWIT ENGINEERING CO. CHECKIED BY AS NOTE0 AF IS A 1 1-- -12 PROJE CT TITLE I HUMBOLDT BAY POWER PLANT PROJECT LOCATION EUREKA, CA JOB NO.12-008-009 PROJECT TASK DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY I Hj rfI LI DRAWING SUBJECT INSTRUMENTATION

& DEWATERING PLAN SHEET NO.8 OP SR RW. I DATE I BY I DATE I BY I D RIPTION CHICO MUNININT PLAZA OMAHA. WE W131 K.E.M.

2.50 SLURRY LINES 04Ix 59CSol~7 00 2. 50 _ LRR IE I~ WLL~I ,2 CEME 9139/I SAN ATIYET T2510 BA Y CLr vl gr i I~_I I I I[ I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I~J~1J~ Liii rny~I I I I I I I I I I I I Lo 1.'r F CLA, ii.E 1-A , -159.1.t I H KI H 1 H 1 t It I i i I I t I 2OR L -PPRSMARY PANEL , SCONDARY PANEL TYP DISCONINECT SWITCH -,, GOXE1-O (Th TVP LURRYlW WALL PANEL ELEVATION~~TiPN SCALE -A'~Nm U INN fib C U C"N~NN C NNI'U 170C OROUND ASSUMED WATER LEVEL 0E EXISYT G0O0N0 lb-2e SLURRY WALL NOTES: FILTER MATERIAL I. TOP OF UNIT F CLAY DEFINED DY GEOTECHNICAL BORINGS PERFORMED BY -0 ROTE ELVTO 12 PERFORATED PVC CONTRACTOR FOR PRELIMINARY DESIGN OF SLURRY WALL TIP ELEVATION IPE (20' SECTIONS)2. PRIMARY PANELS CONSTRUCTED WITH HYDRO-MILL

& SECONDARY PANELS CONSTRUCTED WTH CLAM-SHELL

3. FINAL SLURRY WALL PANEL EXCAVATION SEQUENCE TO BE DETERMINED BY PUMP SLURRY WALL CONTRACTOR AND APPOVED BY PGOE INSTRUMENTATION AND DEWATERING NOTES: 1. INCUNOMETER CASING SHALL BE DGSI STANDARD 2.75 INCH CASING OR APPROVED EOUIVALENT

2. PIEZOMETERS SHALL BE 0GS0 HEAVY DUTY VISRATING WIRE PIEZOMETERS OR APPROVED EQUIVALENT -95.0'+/-3. CEMENT BENTONITE GROUT BACxnLL MIx DESIGN SHALL BE IN ACCORDANCE WITH THE MANUFACTURER'S RECOMMENDATIONS.

FOR INCLINOMETER'S HARD AND MEDIUM SOILS MIX DESIGN SHALL BE USED.4. INCLINOMETER CASING ANCHOR AND GROUT VALVE ARE RECOMMENDED FOR INSTALLATION.

REGARDLESS OF INSTALLATION METHOD CONTRACTOR IS REGRONSIBLE FOR SUCCESSFUL INSTALLATION OF INSTRUMENTATION WHICH SHALL BE VERIFTED WITH BASELINE READINGS 5. ONE SET OF GROOVES IN THE INCLINOMETER CASING SHALL BE PLACED PERPENDICJLAR TO THE EXCAVATION SLOPE I 2 3/4' CASING CEMENT/SIENTONITE GROUT SECTION SCALE -A'EBT OP BOREHOLE & INCLINOMETER t IEL -l00.0" I(I> AII~n Cr- O PRINT IS ONE HALF INDICATED SCALE DESwIGnED By NPU6.09-14-12 G. TA 0oox DRAFT SUBMITTAL K.EM, DR By09--05--12 S.J.H. 90% SUBMITTAL NPG. Sj.hL-715-72 SJH. 10% SUBMITTAL N.P0. KIEWIT ENOINEERING CO. CHECKEDBY SCALE AS NO DATE PROJECT TITLE HUMBOLDT BAY POWER PLANT PROJECT LOCATION EUREKA, CA JO0B NO.12-008-009 PROJECT TASK DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-9 HiI k DRAWING SUBJECT TYP ELEVATION

& SECTIONS BREET NO.9 OF 16 REV.I DATE I BY I DESCRIPTION K.CRKD I KIEn PZ O NE E111S11 K EM I ,

17ýý/STORM WATER PREVENTION NOTES: 1. INSPECTION, CLEANING AND MAINTENANCE OF ALL EROSION CONTROL MEASURES SHALL BE DONE ON A REGULAR BASIS AND PRIOR TO FAILURE OF ANY EROSION CONTROL DEVICE. ALL EROSION AND SEDIMENT CONTROLS SHALL BE INSPECTED AFTER STORM EVENTS AND ON A WEEKLY BASIS. ALL EROSION CONTROL MEASURES SHALL BE PROPERLY MAINTAJNED FOR THE DURATION OF CONSTRUCTION UNTIL THE SITE IS STABIUZED.

2- NO SEDIMENT OR SEDIMENT LADEN WATER SHALL BE ALLOWED TO LEAVE THE SITE WITHOUT BEING FILTERED 3. IF UNFORESEEN SOIL EROSION OCCURS DURING CONSTRUCTION.

THE CONTRACTOR SHALL TAKE ADDITIONAL MEASURES TO REMEDY SUCH CONDITIONS AND PREVENT DAMAGE TO ADJACENT PROPERTIES, BODIES OF WATER AND SEWER SYSTEMS. AS A RESULT OF INCREASED RUNOFF AND/OR SED4MENT DISPLACEMENT.

OR SEDIMENTATION.

4. ANY EXISTiNG CATCH BASINS OR STORMWATER INLETS. SHALL HAVE INLET PROTECTION INSTALLED FOR THE DURATION OF CONSTRUCTION S. STOCKPILES SHALL HAVE MAXIMUM 2:1 SIDE SLOPES AND SHALL BE PROTECTED AND MAINTAINED YEAR ROUND. STOCKPILES SHALL BE COVERED WITH PLASTIC SHEETING WHEN STOCKPILE IS NOT IN USE.6. STOCKPILES SHALL BE COVERED WITH EROSION CONTROL BLANKETS 7. IF DUST/DEBRIS IS DRUG FROM THE SITE INTO THE PUBUC RIGHT-OF-WAY IT SHALL IMMEDIATELY BE SWEPT TO THE SATISFACTION OF THE TOWNSHIP GROUNDWATER TREATMENT SYSTEM SOIL & DEBRIS TESTING AREA MODULE CONTAINER STOCKPILE AREA SOIL STOCKPILE AREA -REUSE & IMPORT FOR BACKFILL SOIL & DEBRIS REMOVAL TRUCK ROUTE CONSTRUCTION EOUIPMENT

& MATERIALS TRUCK ROUTE HBGS ACCESS ROUTE SILT FENCE FIBER ROLLS UMBOLDT BAY-INSTALL FIBER ROLLS INSIDE EXIST FENCE UNE-SEEDETI-STABIUZED CONSTRUCTION ENTRANCE TYP SEE DETAIL 9 STORM WATER PREVENTION PLAN PRINT 1S ONE HALF INDICATED PROJECT LOCATION EUREKA CA JOB NO.12--1 HUMBOLDT BAY POWER PLANT I PROJECT TASK CAISSON REMOVAL FEASIBILITY STUDY IDRAING NO.12-008-0OO-1 DRAWING SUBJECT STORM WATER PREVENTION PLAN SHEET O-.M0 OF 16 AGGREGATE GREATER BUT SMALLER THAN 6*ONC FILTER FABRIC.EXIS T GROUND'mm'I'm 0)C C II.MATCH (gD nvTiON 1. SLT FENCE SHALL BE CONSTRUCTED IN ACCORDANCE WITH CALIFORNIA STORMWATER OUAUTY ASSOCIATION STORMWATER BEST MANAGEMENT PRACTICES 2. SILT FENCE SHALL BE INSTALLED PARALLEL TO EYIST1NG CONTOURS OR CONSTRUCTED LEVEL ALIGNMENTS

3. CONSTRUCT THE LENGTH OF EACH REACH SO THAT THE CHANGE IN BASE ELEVATION ALONG THE REACH DOES NOT EXCEED 1/3 THE HOGHT OF THE UNEAR BARRIER, IN NO CASE SHALL THE REACH LENGTH EXCEED 5G0'4. THE LAST B' OF FENCE SHALL BE TURNED UP SLOPE 5. STAKE DIMENSIONS ARE NOMINAL 6. DIMENSIONS MAY VARY TO FIT FIELD CONDITIONS

7. STAKES SHALL BE SPACED AT 8' MAXIMUM AND SHALL BE POSITIONED ON DOWNSTREAM SIDE OF FENCE 8B STAKES TO OVERLAP AND PENCE FABRIC TO FOLD AROUND EACH STAKE ONE FULL TURN. SECURE FABRIC TO STAKE WITH 4 STAPLES.9. STAKES SHALL BE DRIVEN TIGHTLY TOGETHER TO PREVENT POTENTAL FLOW-THROUGH OF SEDIMENT AT JOINT. THE TOPS OF THE STAKES SHALL BE SECURED WITH WIRE.10. FOR END STAKE. FENCE FABRIC SHALL BE FOLDED AROUND TWO STAKES ONE FULL TURN AND SECURED HITH 4 STAPLES 11. MINIMUM 4 STAPLES PEN STAKE. DIMENSIONS SHOWN ARE TYPICAL 12. CROSS BARRIERS SHALL BE A MINIMUM OF 1/3 AND A MAXIMUM OF 1/2 THE HEIGHT OF THE UNEAR BARRIER 13. MAINTENANCE OPENINGS SHALL BE CONSTRUCTED IN A MANNER TO ENSURE SEDIMENT REMAINS BEHIND THE SILT FENCE 14. JOINING SECTIONS SHALL NOT BE PLACED AT SUMP LOCATIONS is. SANDBAG ROWS AND LAYERS SHALL BE OFFSET TO EUMINATE GAPS 16. ADD 3-4 BAGS TO CROSS BARRIER ON DOWNGRADIENT SIDE OF SILT FENCE AS NEEDED TO PREVENT BYPASS OF UNDERMINING AND AS ALLOWABLE BASED ON SITE LIMITS OF DISTURBANCE RUNOFF WATER ý FIBER ROLL W/SEDIMENT ILTE ED WATER MAX 3/4- WOOD STAKE 0 4.0' SPA FIBER ROLL RUNOFF RATER W/ SEDIMENT FILTERED WATER MAG 3/4- WOOD STARE 0 4.0' SPA ENTRENCHMENT-SLOPED AREA ENTRENCHMENT-FLAT AREA FIRER ROLL NOTES'T. FIBER ROLL INSTALLATION REGUIRES THE PLACEMENT AND SECURE STAKING OF THE ROLL IN A TRENCH, 3-INCH TO 4-INCH DEEP. DUG ON CONTOUR 2. ADJACENT ROLLS SHALL TIGHTLY ABUT 3. RUNOFF MUST NOT BE ALLOWED TO RUN UNDER OR AROUND FIBER ROLL DT BAY POWER PLANT I PROJECT TANK CAISSON REMOVAL FEA DRAWING SUBBJE STORM WATER PREVEN PRINT IS ONE HALF INDICATED SCALE PROJECT LOCATION JOB NO.EUREKA, CA 12-008-009 DRAWING NO.IBILITY STUDY 12-008-009--t OT SHEET NO.iTION DETAILS 1i OF 16 17ýýSOIL NAIL WALL LEGEND SLEGEND DUSCIRPTIONESCAVA1lON V:I OR SLOPE IN DEGREES FROM TVR.1CAI SPOT ELEVATION SOIL NAIL WALL PLAN--l 20'PRINT IS ONE HALF INDICATED SCALE 4 DESIGNED BY N.P., 09--14--12 G. T.F. , K iRAFT -UMTA K.E.A 09-05-12 SJ.H. 90, SUBMITTAL N.P.G., 06-15-72 S.H. 60X SUBMITTAL N.P.GKIEWIT ENGINEERING CO HECKED BY SCALE A AS NO70A sNOA AAU:E DATE AF 06-15-12 INVi7A PROJECT TITLE HUMBOLDT BAY POWER PLANT PROJECT LOCATION EUREKA, CA JOB NO.72-008-009 PROJECT TASK DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-12 lu.1 DRAWING SUBJECT SOIL NAIL WALL PLAN SHEET NO.12 OF 16 REV. DATE BY DESCRIPTION CI CHO I IKEWrr PLAZA 011AA .NE 601311 K.El.E E TVP WALL DETAIL N 10SCALE: OF16 2 L G-0T NOTE: 10 LEVELS OF 25' LONG SOIL NAILS. 4' VERT AND HGRIZ SPA TYP TOP OF SOIL NAIL WALL GEOCOM POSIE DRAIN STRIPS TYP ii ii -ii -ii -i -w i i' -III "III "II -II , IIG iIII III' IIG IIG IIG 'Jim 'Jim G l 11W i I I Gil M11 M1 ml Wi lwl Gil Gil Gil mlI mI 1 I. 11, 11. 11 '11w '11w JM JM JM JM1I I I 119 11w 11w II' ' i I 11w ED1 E 11w-Ii ,i 11 l W11 G il G i i wii G i i ~< '6 6" MIN SHOTCRETE CONSTRUCTION FACING GEOCOMPOSITE DRAIN STRIP (PLACE GEOTEXTILE AGAINST GROUND)GEOCOMPOSITE DRAIN STRIP BENDED AT THE BOTTOM OF SOIL NAIL WALL TO DAIIGHT FOR WATER DRAINAGE 1 14 ý \ BOTTOM OF WALL S-SOIL NAILS I GEOCOMPOSITE DRAINAGE STRIP DETAIL3/8" = 1V-0 TVP TOE DRAIN SECTION scALE 3- -1V-0-PRINT IS ONE HALF INDICATED SCALE PROJECT LOCATION DESIGNED BY i 09- f4 -12 O. TF. OO N DRA F T SUBM ITTAL K ,E.M .DRAW N BY 10 9-05-12 S.H. I SOX SUBMITTAL N.P.G. .SCALE ASN TITL NE R L N AS NOTED HUMBOLDT BAY POWER PLANT SCALE APROJECTT PROJECT IPS=mO CAISSON REMOVAL DATE AF DRAWING S 06-15-12 A- SOIL NAIL WALL ELE PROJECT LOCATION EUREKA, CA JOB NO.12-008-009 TASK DRAWING NO.FEASIBILITY STUDY 12-008-009-13 W06-15-12 SNJ.H. BOX SUBMITTAL B.P.G. KIEWIT ENGINEERING CO. CHECKEDBY lM'J REV. DATE i BY DESCRIPTION CHK'D KIErWIT PLAZA OMAHA. NE CHAEC K. M..UBJECT VATION & DETAILS SHEET NO.13 OF 16

--PROVIDE MIN 2" COVER OVER WELDED WRE MESH-SHOTCRETE CONSTRUCTION BEVELED WASHER FACING II " P -CEN'[AUIZER 0 MAX 8 FT OC ANDý-- -34 PROVIDE CENTRAZERS WIIN 24F WALERS DRI OLEAT EDGE OF PANEL WHERE RE UIRED-TYP SPHERICAL L LAP = 40 BAR _ L NAIL HOLE TYP NUT OR DIAMETERS OR 2.00 MINIMUM O ,0 U TR NAIL HOLE 11RCAL REINFORCING I 2S50. WELDED WRVEMESA REINFORORNG 4.4-W2.9xW2.9 SOI NAIL DETAIL z HTCRETE PANEL CONNECTOR PLATE 131 SC'E .I'-11 SAE NOT I, ALL NAIL REINFORCING

1. 12 REBAR OR 1 1/2-0 GRADE 75 KSI EXIST REINFORCING SHORT CIER CONSTRUC77ON GEOCOMPOSITE DRAIN STRIP EXI1ST REINFORCING FACING SI-ON ICE I EXIST VAIL CONSTALLCNAIL CON CIRCONG OEOCOMPOSFTE DRAIN STRIP STABIUZINS BERM 11101 NAILLODCL EXCAVA nON To LOA CELL IRSTAIJ RAIL FINAL WALL FACE REFERENCE ItAK VRUU A THROUGH DRILLHOLE GOOPST RI TI EXCAVATION UNE .J AC.K HYDRAULIC IN STABILIZING BERM- GEOCOMPOUIE DRAIN STRIP FOR SHOTCRETE BURIED IN BERM (12 MIN EXCAVATION SHALLE /v iiCAION F AVOID HITTING NAILS / BEARING TE CESS AHER EXCAVATING

/N'STABILIZING BERM FNLWL AEml 70 WOOD CRIBBING AND STEEL BEARING t EXCAVATION OF TEMP STABILIZING BERM FOR sHOTCRETE PLACEMENT NAIL INSTALLATION ITHROUGH TEMP S (CON,,ACTOR OPTION, VERIFICATION TEST SOIL ",IL STABILIZING BERM (CONTRACTOR OPTION)SCALE I/2 0 SCALE: ---" I-: SC 2' '- " NOTES: 1. BARE BARS MAY BE USED FOR SACRIFICIAL TEST NAILS 2. PROOF TEST DETAIL IS SAME EXCEPT LOAD CELL IS NOT REQUIRED PRINT IS ONE HALF INDICATED SCALE DESIGNED BY NP.(S0-9---12 .FJ. 10X AFT SUBMITTAL N..G. BRAWN DB A io,-T2 S.J.IH AOSUBMITTAL NAG A 06-15-12 S.J.I B. OX 5159CR TAL N.PCG KIEWIT ENGINEERING CO. 7EHEKEBRY AS NOTED.T.O AL '" k ET S LSS Q*PROJECT TITLE PROJECT LOCATION JOB NO.HUMBOLDT BAY POWER PLANT EUREKA, CA 12-0DB-009 PROJECT TASK DRAWING NO.CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-14 I1DATE AFE DRAWING SUBJECT .GEET NO.d. 0o-15-12 SOIL NAIL WALL DETAILS 14 OF 16 REV. I DATE I BY I DESCRIPTION IICOK IIM rr PLAZA oM-I-UL.HENSl K.E, WEDGE OGHT TO 12.12 TUMBER DEC CONC F 7 OR 1 1/2' S I M ENý7 MANITOWOC 2250 5.06 MIN 10.ý0-V'ARIES 2.0 SOIL NAILTO/SLURRY WAL EXISTING OR.7.: " * * ~~HP14x73

." UP TO 2' ACTIVATED CONCRETE COULD ALREADY SE REMOVED DURING PREVIOUS DECOMMISSIONING ACTIVITY.CONTRACTO TO VERIFY INTEGRITY OF CONCRETE TO RESIST LATERAL LOADING FROM DEMOS EOUIPMENTT EL +.10.00'1"P 4.47' ...FCO 8.01 I OOKSHORING IOKERS TrY NOTE SHORING TOWERS CANNOT RESIST LATERAL LOADING FROM EQUIPMENT CONTRACTOR IS RESPONSIBLE FOR DESIGNING LATERAL RESTRAINTS FOR THEIR PROPOSED EQUIPMENT.

VA TOR M 2pR'DECK RrNI"N CONC UFT JOINT.EL -34.011 CONG RINGBM: WP14.73 GRILLAGE FRAME WELDED TO~ALLOW REMOVAL AS A SINGLE UNIT CONC fFTJOINT EL 4-47.____ !X X ccI cc 41 cc Ii.-- AZ-36 1ip FINISH FLOOR TRFMIF ql1AR RA-F fl~EET PILE t2l. ýýEL{I*L --IRU T SLURRY WALLo EL -51.' TO -172.0P SECTION. LOWER CAISSON DEMO-CL:1 -lo'STAGE I: UPPER PORTION OF REACTOR BUILDING STRUCTURE REMOVED. INSTALL SHORING PLATFORMS, POSITION EXCAVATOR IN CENTER OF CAISSON. DEMO TRST LIFT OF EXTERIOR WALLS AND EXCAVATE SOIL TO 12' MAX EXCAVATION PAST CENTER OF PREVIOUS RING BEAM PRINT IS ONE HALF INDICATED SCALE DESIGNED BT N.P.(09-14-12 G. TF. 1OXO DRAFT SUBMITTAL KE.M. K ie v t RAWN A 109-05-12, S.J.H. 1 90X SUBMITTAL N.PG. SG,,h A PROJECT TITLE P AS NOTED HUMBOLDT BAY POWER PLANT I- A PROJECT sc, REMOVAL I DRAWINGO 06-15-12 DEMOLITION EQUI PROJECT LOCATION EUREKA CA JOB NO.72-008-0O9 T TANK DRAWING NO.FEASIBILITY STUDY 12-008-009-15 A 06A-T5-T2IL.IH.I

& 106-15-121 S-M I 6OX SUBMITTAL N.R.G. KIEWIT ENGINEERING CO. CHECKED BY I DESCRIPTION CHRO KBSWfl PLAZA O*MIAHA. NB SS13 K. KEM.SUBJECT PMENT SUPPORT SHEET NO.15 OF 16 REV. DATE I BY I

-SLURRY WALL TYP EXISTILG GRADE EL+2.0';SOIL RING BEAM

SUMMARY

ELEVATION CINCiRETE ALT.NAPIr Vc.... W EBE*( 3T) iEAM IE SE BEIAN (.y) (KIPp)______ (IN) sizE-34.0 39 W36.232 98.3 58.3-46.5 44 W36.302 125.1 75.9 4 -59.0 43 W36.302 119.5 75.9 LEVELS -71.5 38 W36x194 93.3 48.8 436.3 258.9-33.0 34 W36B170 74.7 42.7-43.0 44 W 36 .247 125.1 62.1 5 ,-53.0 44 W36 .247 125.1 62.1 LEVELS -83.0 44 W36 .247 125.1 62.1-73.0 34 W ,36 .170 74.7 42.7 TOTAL 524.9 271.7 CONIC EIT J04INT4 EL 1111'III ID)C C III III.C mm'III t 0.CONEC uFT JOINTo EL -47.0'FINUR P622 61o NO TE: 1. CONCRETE RING BEAMS HAVE BEEN OESIGNEO AS CAST IN-PLACE CONCRETE.

CONTRACTOR TO DEVGN REINFORCING STEEL ANY CONNECTON DETAIL TO SHEET PILE WALL/(. 28 SAY COMPRESSIVE STRENGTH IS REQUIRED BEFORE PROCEEDING WITH EXCAVATION UNLESS APPROVED BY ENGINEER TREMIE SLAB BASE EL OF 4,0DoN BOT OF EXCAVARI Np EL -80."1 EL-V'SECTION -CAISSON DEMO COMPLETE SCAW : I" -10 PRINT IS ONE HALF INDICATED SCALE HUMBOLDT BAY POWER PLANT LTNO.PROJECT TASK CAISSON REMOVAL FEASIBILITY STUDY B RAWING NO.12-008-009-DRAWING SUBJECT SHEET PILE & RING BEAM SHEET NO.i's OF .6 HUMBOLDT BAY POWER PLANT EUREKA, CALIFORNIA JOB NUMBER: 12-008-008 UNITS 1 & 2 FOUNDATION REMOVAL FOUNDAflON REMOVAL AREA Ai t VICINITY MAP PROJECT SITE SCALE- Nfl SCA.: NTS.FEASIBILITY STUDY PREPARED BY:@ Kiewit KIEWIT ENGINEERING CO.KIEWnT PLAZA OMAHA. NE 66131 DISCLAIMER: "HNE INFORIATION CONTAINED HEREIN I1 INTENDED AS A "PROOF OF CONCEPT AND IS GENERAL IN NATUREr. IT SALL NOT 0 0CO4ST1IRUED AU CONTAINING ALL INFORIMATION NE.QUINE1D TO PEWORNiINS T RIL CONTYRWIN SNALL WE RESPONSIBLE FO1t INDEENNENTLY VALIDATING ALL ELEWENTS tO DESIGN AND PROVIDING ALL REGMUIRED ENGINEERING N!ECWSANY TO SUIT ITS OWN MEANIS AND MERTHODIS FOR EXECUTING THIE WO"IL SEN ER A NOTE&S 1. ALL DIMENSIONS AND ELEVATIONS ARE IN DECIMAL FEET UNLESS NOTED OTHERWISE 2- CONTRACTOR IS RESPONSIBLE FOR OBTAINING ALL REQUIRED PERMITS ASSOCIATED WITH THE WORK 3. BASE TOPOGRAPHIC.

SITE. AND UTILITY PLANS AERE PROVIDED BY PG&E. NORTHING AND EASTING COORDINATES ARE BASED ON NADO3. ELEVATIONS SHOWN ARE BASED ON NAVD 88..COMPACTION OF SAND FILL SHALL BE PERFORMED USING A VIBRATORY DRUM ROLLER S. COMPACTION OF CLAY FILL SHALL BE PERFORMED USING A SHEEPS FOOT ROLLER B. EXCAVATION AND BACKFILL TO BE PERFORMED IN ACCORDANCE WITH CONTRACT SPECIFICATIONS.

EXCAVATED SOIL SHALL BE CHARACTERIZED IN ACCORDANCE WITH THE NRC/DTSC APPROVED REMOVAL ACTION WORK PLAN FOR EXCAVATED SOIL AND FOR ON-SITE RE-USE AS BACKFILL 7. TIMBER PILE AND FOUNDATION LOCATIONS.

SECTIORS AND DETAILS ARE BASED ON: TIMBER PILE PLACEMENT

-SHEET #418767 REV 1. 417101 REV 3. SHEET 417102-3 REV 3 AND SHEET 417103 REV 2 8. FOUNDATION LOCATIONS FOR UNITS 1 AND 2 TO BE FIELD VERIFIED N. VOIDS LEFT AFTER PILE EXTRACTION SHALL BE FILLED WITH MINIMUM 50 PSI CLSM CONCRETE .ABV ABOVE ADJ ADJJST/ADJUSTABLE ALT ALTERNATE ALUM ALUMINUM ANCH ANCHOR/ANCHORAGE APPROX APPROXIMATELY 0 AT AVG AVERAGE BEL BELOW BLDG BUILDING EBK BLOCK B SI REAM BOC BOTTOM OF CONCRETE SOT BOTTOM BOW BOTTOM OF WALL Bp BASE PLATE/BEGIN POINT MC BEARING BRKT BRACKET BTWN BETWEEN BVCE BEGIN VERT CURVE ELEV BVCS BEGIN VERT CURVE STATION BW BOTH WAYS CC CENTER TO CENTER CARS CAISSON CAP CAPACITY (i CENTERUNE OF CUBIC FEET CHAN CHANNEL CJ CONTROL JOINT CLG CEIUNG CUR CLEAR CLSM CONTROLLED LOW-STRENGTH MATERIAL COG CENTER OF GRAVITY COL COLUMN CONC CONCRETE CONN CONNECTION CONST CONSTRUCTION CONT CONTINUOUS CONTR CONTRACTOR CTR CENTER CU FT CUBIC FOOT CU YD CUBIC YARD B DIAMETER ORL DOUBLE DEG DEGREE DEMO DEMOUSH/DEMOUTION DIRAG DIAGONAL DN DOWN DWO DRAWING EA EACH EL ELEVATION EMBED EMBEDMENT ENGR ENGINEER EP END POINT ES EQUAL EQUIP EQUIPMENT EVCS END VERT CURVE STATION EVCE END VERT CURVE ELEV EW EACH WAY EXIST E STING EXP EXPANSION FF FINISH FLOOR FLS FLANGE FND FOUNDATION FT FOOT FTG FOOTTNG CA GAUGE GALV GALVANIZED GOvT GOVERNMENT HGRND GROUND NCR HORIZONTAL CONTROL LINE HORIZ HORIZONTAL ID INSIDE DIAMETER!E INVERT ELEVATION INV INVERT JST JOIST JT JOINT K KIP = 10i 0 LBS KOI KIPS PER OSQUARE INCH L ANGLE* PLUS OR MINUS LBS POUNDS LU LONG LLH LONG LEG HORIZONTAL LLV LONG LEG VERTICAL MAO MAXIMUM MECH MECHANICAL MFR MANUFACTURER MIN MINIMUM MISC MISCELLANEOUS NO. NUMBER NTS NOT TO SCALE OC ON CENTER OD OUTSIDE DIAMETER OPNG OPENING It PLATE PC PRECAST PERP PERPENDICULAR Pi POINT INTERSECTION PLF POUNDS PER LINEAR FOOT PLWD PLYWOOD PNL PANEL PSF POUNDS PER SOUARE FOOT PSI POUNDS PER SQUARE INCH PM POINT OF VERT INTERSECT R RADIUS RCSC RESEARCH COUNCIL ON STRUCTURAL CONNECTIONS REINF REINFORCEMENT RECD REQUIRED REV REVISION OCRED SCHEDULE SF SQUARE FOOT SiM SIMILAR SPA SPACING SPECS SPECIFICATION STA STATION STD STANDARD SOFF STFFENER STL STEEL ST STREET SW. SAFE WORKING LOAD T&B TOP AND BOTTOM TBD TO BE DETERMINED THK THICK / THICKNESS TOO TOP OF CONCRETE TOF TOP OF FOOTING TOP TOP OF PIER TOS TOP OF STEEL TOW TOP OF WALL TYP TYPICAL UNO UNLESS NOTED OTHERWISE VERT VERTICAL W/ WITH W/o WITHOUT WD ROO DETAIL INDICATOR SHEET 0 FROM / -SECTION OR DETAIL WMICH SECTION EEL.- SHEET I -NERE OR DETAIL IS CUT-.iJ SECT FN OR DETAIL CAN BE FOUND SHEET INDEX NO. DRAWINO SUBJECT 1 C1ENERAL NOTES 2 SENERAL ARRANGEMENT PLAN 3 SITE USE PLAN STORM. SEWER WATER, & OIL UTIUTIES PLANL4J TII'n~IIIrlnMi~lrT1HCIA ELECTRIC & TELECOMMUNICATION UTIHMrS PI Al FOUNDATION REMOVAL IIf S FOUNDATION REMOVAL PLAN & SECTION ft 0.zj DESIGNED BY N.P.09-13-12 0. Cr TO.t DRAFT SUBMITTAL KEt BDRAWN BY A, 09- -2 S.J.H. 9 OX SUBMITTAL SPJ PRINT IS ONE HALF INDICATED SCALE PROJECTTILE PROJECT LOCATION JOB NO-HUMBOLDT BAY POWER PLANT EUREKA, CA 12-008-008 PROJECT TASK I DRAWING NO.UNITS I & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-oo0-oo08-R 6- 5-D2AT.E.H.

HOt SUBRIPTAL N.P. KIEWIT ENGINEERING CO. OBECKEDO .R D. ATE IBY DESCRIPTION EKE'S KIEfWE PLAZA OMRAN,% NE 501311 K E.DRAWING SUBJECT RSEET NO.GENERAL NOTES +/- OF 5 PLANT LOCATIONS NO. DEUCPTO RIO NO. Oluboll" ION NO, UCIMMO I ON NO. DUCRPTI ON I UNIT REMOVED 12-5 DECOM SAFETY TRAILER 24-A RMS 32 RIGGING STORAGE -REMOVEDS 2 UNIT REMOVED 12-6 ENGINEERING TRAILER 24-B HASKELL SAFETY TRAILER 33 NOT USED 3 UNIT NUMBER 3 12-7 ENGINEERING TRAILER 24-C FINANCE 34 SHEPHERDS SOURCE 4 HOT SHOP 13 COUNT ROOM 24-D NORTH COAST FABRICATONS 35 UNIT 3 WORK CREW BLDG S OFFICES. SHOPS. & WAREHOUSE 13-A FOSSIL DECOMMISSIONING TRAILER 24-E RADWASTE 36 HBGS WORK SHOP 6 ADMINISTRATION ANNEX 13-8 RVP OFFICE TRAILER 24-F WARTSILA OFFICE TRAILER B 37 HBGS CONTROL ROOM 7 TRAINING/NETWORK BLDG 14 SOUD RADWASTE HANDLING BLDG 24-H FRONT OFFiCE/ENVIRONMENTAL 38 HBGS MB-BLDG/CONTROL a SECURITY BLDG 15 LOW LEVEL RADWASTE BLDG 24-I PROCUREMENT TRAILER 39 HRGS ENGINE HALL 9 FS -TRAILER 16 ULUID RADWASTE BLDG 24-J DECOM 6-MDE OFFICE TRAILER 40 HBGS LV-ROOM 10 ASSEMBLY BLDG 17 RP INSTRUMENTATION BLDG 25 OFFICE TRAILER 41 HBGS FIREPUMP HOUSE 10-A INITIAL TRAINING AND BADGING 16 UNIT 3 ACCESS CONTROL 26 PAINT/SANDBLAST BLDG 42 HBGS TEMP OPERATIONS

-REMOVED 11 PRIMARY ALARM STATION (PAS) 19 27 HBPP FIREPUMP HOUSE -REMOVED WACH'S TRAILER -REMOVED 12-1 GENERAL ENGINEERING TRAILER 2D RADWASTE OFFICE TRAILER B 26 MOBILE EMERGENCY POWER PLANT 1 -REMOVED 44 RUBS TERT 12- ELECTRICAL ENGINEERING TRAILER 21 HAZARDOUS WASTE STORAGE 21 MOBILE EMERGENCY POWER PLANT 2 -REMOVED 45 FUTURE USE 12-3 MECHANICAL/PIPING ENGINEERING TRAILER 22 NEWGEN/RP S-WIDE OFFICE TRAILER 30 MEPP ISLAN BLDG 12-4 CISIL/STRUCIURAL ENGINEERING TRAILER 23 FUTURE USE 31 RELAY BLDG' ~CONTRACTOR FOOTPATH /-PRIN Is QN A FI DI A E C 2 C:3 2C 12 12--N AK IN 2""U RJC TS RWN O IOOX~~~~~~O 8RF UMTALDANB REV. ~ ~ ~ ~ ~ ~ ~ WRAA DAE BADSRPIO H'D[Kjwfn

= O okJgJNEn r11 ,EM. 6GNRLARNEETPA PRINT15 OE HAL INDCATEDSCAL 09-IJ-12~~GEN RA ARRAN EMEN PLAN~rSUM~A ROET KDRWN O A 09-10-12 S.JH. oCx SUBMITTAL N.P. I C~00I UNITS .IN& 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-0OA8-008-2 AA 06-15-12 SJI. BOX SUBMITTAL N.Pr NI IEWIT ENGINEERING CO. CHECKED BTY DABTE ~ FE Y DRAWINGSUBJECTSETNO REV.J DATE NT DESCRIPTION CR60 MKIEIT PLAZA OMAHA. WNE 68131 K E. M. 08-13-12 GENERAL ARRANGEMENT PLAN 2O SITE USE SCHEDULE LI., ND NO. I0 lmrlON AREA IFllr 1 CONSTRUCTION WORK AREA 1,792 2A GROUNDWATER TREATMIENT SYSTEM 8,120 2B GWITS RECEIVER TANK 383 3A WASTE MANAGEMENT FACILITY 12.000 38 DEBRIS TESTING AREA 5.250 4A INTERMODEL CONTAINER STOCKPLE AREA 26.286 (NTEIN ODEL CONTAINER STOCKPILE AREA 8.379 SOIL STOCKPILE AREA 30.80 SOIL STOCKPILE AREA 33.751 SA CONTRACTOR OFFICE TRAILER 1,440 8B CONTRACTOR OFFICE TRAILER 2.700 LI 7 HBGS -OPERATING POWER PLANT N/A[8 B CAISSON REMOVAL AREA N/A-BUILDINGS

/ STRUCTURES TO REMAIN N/A-INTERMODEL TRUCK ROUTE N/A-CONSTRUCTION EQUPMENT & MATERIALS TRUCK ROUTE N/A-ITE WALKWAY PATH N/A HBGS ACCESS ROUTE N/A-CONSTRUCTION ENTRANCE N/A SOIL STOCAIPILE AREA NOTESi I. TRAILERS BILL REED TO BE MOVED FROM AREA SA BY JANUART 1. 2014 FOR STOCK PILE CON STRUC TI ON 2. A PORTiON OP AREA 5A BILL BE OPEN FOR TRUCK TURNAROUND PURPOSES INS cc PRINT IS ONE HALF INDICATED SCALE SCALE ttPROJECT TITLE. PROJECT LOGAT)ON JOB NO.AS NOTED HUMBOLDT BAY POWER PLANT EUREKA. CA 12-008-"O8 F ST tS -1 .- = PROJECT TASK DRAWING NO.-T -so UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-008-008-3 ATE DRAWING SUBJECT SHEET NO.06-1J-72 SITE USE PLAN 3 OF S 4jKEWrr ENGINEERING CO. ICHECKED BYT CR8.0; KINAW PtfffA OHWAINA. NE M131 K RAI LEGEND-- --STORM DRAIN PRESSURE SEWER--a -SANITARYSE R FRESH WATER-FIRE WATER PIPES 14" PG&E COL UNE... UTIUTY TUNNEL 9 IN.IRN C C uN INN C BNI Iii UTILmIES PLAN SCALE: 1, .PRINT IS ONE HALF INDICATED SCALE rTA-L K7- tN.P.C IOOX DRAFT SUBMITTAL DRAWN BY 90. SUBITAL 1.J1-0 2 60X SUBMITTAL KIEEWIT ENGINEERING CO. CHECKED BY SCALE PROJECT TITLE PROJECT LOCATION JOB NO.AS NOTED HUMBOLDT BAY POWER PLANT EUREKA. CA 12-008-008 IT 'I PROJECT TASK DRAWING NO.--T UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-008-008-4A DATE DRAWING SUBJECT SHEET R .STORM, SEWER WATER, & OIL UTILITIES PLAN OF 5"I'jt iREV. I DATE I BY I DESCRIPTION CHWD MKWrr PLAZA OMAHA. ME W131 K.E.M.

LEGEND ITEM DESCRIPTIONOVERHEAD POWER-- UNDERGROUND POWER-TELECOMMUNICATIONS CONDUIT RIBER OPTIC HU.BOLDT BMY JI.7 it ccN U)V6 sCA : 1, -IBA'PRINT IS ONE 4AJLF INDICATED SCAA PROJECT LOCATION EUREKA, CA JO1 NO.12-008-HUMBOLDT BAY POWER PLANT I PROJECT TASK UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY I DRAWING NO.DRAWING SUBJECT ELECTRIC & TELECOMMUNICATION UTILITIES PLAN FOUNDATION SCHEDULE TYPlE QrY PILKS PER TOe EL CONC VOL CAP (P1 (cu YO)A/1 4 3 12.00 8 ciD 4 14 12.00 155 E./F _ 4 16 12.00 _ 200 G/H_ 4 14 9,43 155 J 2 69 VARIES 390 SSUPPORT PERMANENT STRUCTURES AS REQUIRED DURING FOUNDATION DEMOUTION

& PILE REMOVAL TOP PILE CAPIGROUND SURFACE EL VARIES INN ZN cc)a V6 ,MAX PILE PP r,- TYPICAL PILE & CAP SECTIONýL ->SCALE W/V" -"-o*FOUNDATION PLAN SCAL I" -2a PRINT IS ONE HALF INDICATED SCALE DESIGNED BY 09-.3-12 G.F. b00 DRAFT SUBMI Kiew it 1RANBY A 09-10-12 S.J.H. 90X SUBMITTAL NP .SJ ,I AS NOTED O'_- 13-2 L PROJECT TITLE I HUMBOLDT BAY POWER PLANT PROJECT LOCATION EUREKA. CA IJOB NO.12-008-008 PROJECTTASK I DRAWING No.UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-008-008-5 A, Inx-,-,I R-IM IJ A 106-15-121 SJ.H I 6ox SUBMITTAL N.P.G. KIEWIT ENGINEERING CO. CHECKEDRY JJU DESCRIPTION CHK'D IKiETrr PLAZA OMAHA. NE 68131 E.M. ik I-DRAWING SUBJECT FOUNDATION REMOVAL PLAN & SECTION SHEET NO, S OP 5 REV.I DATE I BY I

@ Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX B WORK BREAK DOWN STRUCTURE

&BUDGETARY ESTIMATE Page 160 HBPP CAISSON DEMOLITION FEASIBILITY STUDY WORK BREAKDOWN STRUCTURE WBS Client CBS Position Description (T) Unit of Unit Cost TOTAL COST Code Code Quantity Measure 1 2.1 Project Management/Supervision 43.00 Mo $197,040 $8,472,713 1 2.2 Office Rent, Utilities and Staff Expenses 43.00 Mo $31,899 $1,371,671 1 3.1 Safety, Quality, Business, Testing & Survey 43.00 Mo $80,308 $3,453,244 1 3.1.5 Design, Engineering and Consultants 1.00 LS $2,561,808

$2,561,808 1 3.2 Temporary Work, Mob, Power, Access 1.00 PLS $2,048,714

$2,048,714 1 3.5 Maintenance Equipment 43.00 Mo $20,432 $878,584 Total 47 ADMINISTRATION SCOPE 1 $18,786,734 1 5.1.1 Concrete Removal (EQP) 6,908.00 Cy $1,773 $12,246,157 1 5.2.1 Machine Access for Demolition (EQP) 1.00 PLS $2,586,186

$2,586,186 1 5.3 Turbine Building Slab Demo 1,150.00 Cy $649 $746,308 1 5.5.1 Spoil Stockpile Facility 64,000.00 SF $27 $1,748,945 1 5.6 Decon Equipment 15.00 Ea $24,160 $362,394 1 5.9 Access equipment and Supplies 1.00 LS $469,837 $469,837 1 7.1 Structure Excavation 17,123.00 Cy $265 $4,536,848 1 7.2 Structure Backfill 25,515.00 Cy $192 $4,904,218 1 7.3 Turbine Building Exc and Backfill 4,505.00 Cy $156 $704,456 1 7.6.1 Environmental Compliance 43.00 Mo $57,664 $2,479,537 1 7.6.2 Dewatering Wells and Maint--Subcontract 1.00 LS $5,344,342

$5,344,342 1 8.2 Sheet Piling (EQP) 21,348.00 SF $114 $2,437,973 1 8.3 Shoring -Soil Nails 15,965.00 SF $140 $2,230,690 1 9.1 Concrete Ring Beams 538.00 CY $1,224 $658,344 1 Total 58 SCOPE 1 -CAISSON DEMOUTION

$41,456,235 Grand Total Scope 1 $60,242,969 2 2.1 Project Management 5.00 Mo $115,416 $577,079 2 2.2 Office/Staff Expenses 5.00 Mo $18,685 $93,425 2 3.1 Operational

& Compliance Support 5.00 MO $47,040 $235,202 2 3.1.5 Design and Engineering 1.00 LS $174,485 $174,485 2 3.2 Temporary Work 1.00 PLS $138,610 $138,610 2 6.1 Unit I & 2 Demolition 2,860.00 Cy $998 $2,854,046 2 6.2 Unit 1 & 2 Excavation and Backfill 7,600.00 Cy $123 $935,066 Total 15 SCOPE 2 -UNIT 1 & 2 DEMOUTION

$S,007,913 3 Slurry Wall Administration 7.00 Mo $4,341,483 3 7.4 Pre-Trench/Piles/Cut&Cap/BF 8,000.00 Cy $151 $1,209,258 1 7.2 Stockpile Area 1.00 LS $2,767,835

$2,767,835 1 5.4 Demo Concrete Clear Zone 485.00 Cy $600 $291,000 3 8.1 Slurry Walls (EQP) 125,901.00 SF $73 $9,203,675 11 3 Total 6 SLURRY WALL$17,813,251

[Grandotal 26 Grnd Toal $8,043

-OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX C LEVEL-i SCHEDULE Page 162

'atfornia High Speed Rail Classic Schedule Layout 23-Sep-12 08:31 k~ftp 10 IACIMIsr Nem. 8ql~ Iedoeshaev Ca~arrdl 2013 I 2014 1 2016 IJj 2016 IIIi~ 12017 12D16----.. ........i .A ... ........11. .................Project , A m nis r tv tetn Ari inini sa ttitsi~ i i l i i i i i i ii i i i 1000 1010 1020 1030 1050 1060 1070 1860 1040 Articipated Award Anticipated Notice to Proceed Mob Office SubmirtApprove Schedule SubmitlApprove Camson De-o Plan Submit/Approve Sheet Piles Submit/Approve Excavation/Backdll Subirdt/Approve InstruerentaboclEnginneering Submit/Approve Slurry Wall 33 04-Feb-13 20-Mar-13 0 21-Mar-13 10 21-Mar-13 03-Apr-13 60 04-Apr-13 26-Jun-13 60 04-Apr-13 26-Jun-13 60 04-Apr-13 26-Jun- 13 60 04-Apr-13 26-Jun-13 60 04-Apr-13 26-Jun-13 60 23-May-13 14-Aug-13 1000 1010 1020 1020 1020 1020 1020 1020 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek PGEUtlty-co Reov 1165 1295 1155 1185 1215 1225 1245 1255 1265 1175 1275 1285 1235 Remnove Equip fiom Hot Shop Backfill Turbine Bldg Structures Perform Sod RercediaSon Demo SAS to elo +9/BackW CP-7, CP-6 Remove UG obstruconstsystem CP-6, CP-5, CP-4 Reronve UG obstr ucionso CP-4, CP-3, CP-2 Remove Slope to Grade&lr CP-4, CP-3, CP-2 Remove UG Systems Eas CP-2, CP-, CP-11 Remove UG obstructions Demo Hot Shop/Rennove Stab CP-11 Reroute 480V Cold & Dark power cab CP-11, CP-10 Remove UG obstrauctons/syste Relocate Access Control Trailer 40 04-Feb-13 29-Mar-13 11 01-Mar-13*

15-Mar-13 109 01-May-13*

30 Sep-13 43 01-May-13*

280Jun 13 20 03-Jun-13' 28-Jun-13 22 01-Jul-13' 30-Juol13 11 01-Aug-13' 15-Aug-13 12 16-Aug-13*

02-Sep-13 65 03-Sep-13' 02-Dec-13 1215 1225 1245 1255 1265 1275 1285 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek 41 Anbpilpatd S4hidc to Prdciled SrbeIprave Scbeidile; Subr/Appra ve C Pla .em..o ..t= tbirrVApre

$tenta f lrlps.k .: .I .+ .+ pl .r I i ,m .i +. + : ik iL:+ ýl]: I ~. :__StiboatAppreve hrborootascrdrerefong Surr~tA0pir&

e Sta.rry Wall 03r14. P136 Ullity Deconp"bov ji Eaýk!l Tcbloe kBlgStrbuctibrres 0 OP 7, CPOP6 eRmodeUG bettrbuoalattrr nFSooth ydrd&" C-, CF-e. cP- Retrieve UD vtnsuoryesrstrnevroEast ot tor brte eBdg I CP-4, Op-.3, CP-2. Reeorn Slope to GradelirntallPiles 12CP-4. CF-S,:. C2' R6"mohe UG Syste"n Badt oRff J ..De Hbt.S....IR.nt eStal j P oF eiri Rcea 48D4 Ckid 6 Dark trower cables: Sq CF-11: OP-iF R-reoveLUG okhstrdcbnohsyterTs

• .+ 0 Reb oc te c e vJ rdro-Tri++~rkr.

+.ii 44 01-Oct-13' 7 03-Dec-13 15 12-Dec-13 23 02-Jan-14 29-Nov-13 11-Dec-13 01 -Jan- 14 03-Feb-14 SlUrry Wall Cotistruction

ý; ý I 1150 1160 1170 1180 1080 1090 1890 1100 1110 1181 1120 1130 1190 1140 Demo Unit 2 Slab Eneentelyhornrpt,!

PirPIs 184 EABacfl!Insoale Wells Install Instrumontation Pre-trench Guide Wells Spoil Managenont Area Install Mob Slurry Wa# Equapment Set-up/Test Slurry Wal Equapmnent Move Trailers Install Panels 84 EA Demob Skirry Wall Equrproent Unwater Clean-up/Move Out 32 06-Jun-13 5 17Jvn-13 20 27-Jun-13 20 25-Jul-13 26 27-Nov-13 10 19-Dec-13 40 29-Dec-13 5 02-Jan-14 10 09-Jan-t14 0 B4 07-Feb-14 10 05-Jun-14 60 05-Jun-14 5 19-Jun-14 19-Juo-13 02-Sep-13 24-Jul-13 21-Aug-13 01-Jan-14 01 Jan 14 07 Feb-14 00-Jan-14 22-Jan-14 10-Jan 14'04-Jun-14 18-Jun-14 27-Aug-14 25-Jun-14 1030 1150 1860 1170 1160,1285 1040,1080 1040,1181 1080 1100 1110.1090.1890 1120 1180,1120 1130 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek a-1 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek P: Deno Unit2 Slab;01, Ihstall llstrantatwn q Comde Web!M oSPil Management Area Install: I Mob$kir rrryWfEquEprmnei o: Sel-aprblthISojrry WaON Erjcqlmrhe

• Move:Tradets

7P lrwstal!Panel 64 PA I) De~rabSiurry We Equiprceot F= r :riwvter 1! OlC -opokdH Dot C aiso Demoatio 1200 2320 1210 1220 1230 Demo Turbine Bldg Slab 1200 CY RFB Slab Demo Excavate 2000 CY Pul Piles 143 EA Badcfill 20 07-Juo-15 15 04-Aug-15 5 25-Aug-15 23 01-Sep-15 10 02+Oct+15 03-Aug-15 24-Aug-15 31-Aug-15 01-Oct-15 15-OCdt15 1050,1120,2190 1200 1070. 2320,1140 1210 1220 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek AN Darrro Tyrtrrrre Bllg $i512k OY IF RFBStailDe"nl

: : : :: : :: : : : : : :: q::-: :. .:: : : : : : ::: :: :: :: :: : : :: : : 11 Excavate 2060 ry C$I P1 Pilese143 EA: BaCkfill : Actual Work Crircal Remaining Work Vmmmm Sumnmnary Page 1 of8 ASK filter: All Activities Remrining Work

• 4 Milestone C Oracle Corporatior

,ak ornia High Speed Rail I Classic Schedule Layout T- 23-Sep-12 08:3C 11111 Pnadeeees1 ae1 IJ111 1A 1 8 1240 1250 1260 1270 1280 1290 1300 1310 1320 1330 1340 1350 1360 1370 2330 1380 1390 1400 1410 1420 1430 1440 1450 1460 1470 1480 1490 1500 1510 1520 1530 1540 1550 1560 1570 1580 2340 1590 1600 1610 1620 1630 1640 1650 1660 1670 1680 Install Falework in Center Tower Esrst Fly Equip/Bridge In +12 to +6 Bsrit Excavation

+12 to +6 Bsrnt Soil Nails Instal +12 to +6 (LI)Bsat Demo Concrete +12 to *6 Bsr6t Fly Equip/Bridge DOt +12 to +6 Bs6t Fly Equip/Bridge In +6 to +2 B6mt Excavabon

+6 to +2 Bs6m Soil Nails Instal +6 to +2 Bs6t Demo Concrete +6 to +2 Bsmt Fly Equip/Bridge Out +6 to +2 Bsnrt Fly Equip/Bridge In +2 to -2 Bsmnt Excavation

+2 to -2 (L3)Bs.t Soil Nails Instal +2 to -2 Adjust Center Tower to El -14 Bs6t Demo Concrete +2 to -2 Bsrnd Fly Equip/Bridge DOt +2 to -2 Bsmt Fly Equip/Bridge In -2 to -6 Bs"4 Excavation

-2 to -6 (-4)Bs6t Soil Nails Install -2 to -6 Bs6rt Demo Concrete -2 to -6 Bs6d Fly Equip/Bridge Out -2 to -6 B6t. Fly Equip/Bridge In -6 to -10 Bs6 t Excavaon r-6 to -10 (-5)Bsrrd Soil Nails Instal -6 to 10 Btnst Demo Concrete -6 to -10 Bsmt Fly Equip/Bridge Out -6 to -10 Bsmt Fly Equip/Bridgeln

-10 to -14 Bs6 t Excavation

-10 to -14 ([6)Bs6. Soil Nails Instal -10 to -14 Bs6t Demo Concrete -10 to -14 Bs6. Fly Equip/Bridge Out -10 to -14 Bsmt Fly Equip/Bridge In -14 to -19 Bs6. Excavation

-14 to -18n (LT)Bs6t Soil Nails Instal -14 to -18 Bsrnt Demo Concrete -14 to -18 AdjustAI Towers to El -30 Bsmt Fly Equip/Bridge Out -14 to -18 Bs6t Fly Equip/Bridge In t18 to -22 B64t Excavation

-18 to -22 (-8)B6.t Soil Nails Instal -18 to -22 Bans Dermo Concrete -18 to -22 Bs6t Fly Equip/Bridge Ot -18 to -22 Bsmt Fly Equip/Bridga In -22 to -26 Bsmt Excavation

-22 to -26 (L)Bs6t Soil Nails Instal -22 to -26 Bs6nt Demo Concrete -22 to -26 5 16-Oct-15 1 23-Oct-15 6 26-Oct-15 3 03-Nov-15 12 06-Nov-15 1 24-Nov-15 1 25-Novw15 6 26-Nov-15 3 04-Dec-15 12 09-Dec-15 1 25-Dec-15 1 28-Dec-15 6 29-Dec-15 3 06-Jan-16 4 09-Jan-16 12 12-Jan-16 1 28-Jan-16 1 29-Jan-16 6 01-Feb-16 3 09-Feb-16 12 12-Feb-16 I 01-Mar-16 I 02-Mar-16 6 03-Mar-16 3 11-Mar-16 12 16-Mar-16 1 01-Apr-16 I 04-Apr-16 6 05-Apr-16 3 13-Apr-16 12 18-Apr-16 1 04-May-16 1 05-May-16 6 06-May-16 3 16-May-16 12 19-May-16 15 07-Jun-16 1 21-Jun-16 1 22-Jun-16 6 23-Jun-16 3 01-Ju1-16 12 06-Ju1-16 1 22-Ju -16 1 25-Ju1-16 6 26-Ju4-16 3 03-Aug-16 12 08-Aug-16 22-Ot-15 23-Oct-15 02-Non-15 S5-Non-IS 23-Nov-15 24-Non-15 25-Nov-15 03-0ec-15 08-Dec-15 24-Dec-15 25-Dec-15 28-Dec-15 05-Jan-16 08-Jan-16 12-Jan-16 28-Jan 16 29-Jan-16 01-Feb-16 09-Feb-16 12-Feb-16 01-Mar-16 022Mar-16 03-Mar-16 11 Mar-16 16-Mar-16 01-Apr-16 04-Apr-16 05-Apr-16 13-Apr-16 18-Apr-16 04-May-16 05-May-16 06-May-16 16-May-16 19-May-16 06-Jun-16 21-Jun-16 22-Jun-16 23-Jun-16 01 -Jul,-16 06 Ju4l16 22-Jui-16 25-Jul-16 26-Ju1-16 03-Aug-16 08-Aug-16 24-Aug 16 1230 1240 1250 1260 1270 1280 1290 1300,1190 1310 1320 1330 1340 1350 1360 1370 1370, 2330 1380 1390 1400 1410 1420 1430 1440 1450 1460 1470 1480 1490 15D0 1510 1520 1530 1540 1550 1560 1570 1580 2340 1590 1600 1610 1620 1630 1640 1650 1660 1670 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek St0nd4,d 5 Dey Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek a-1 Standard 5 Day Workweek Standard 5oay Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Stand1rd 5 Day Workwnek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek a-1 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek I: OýaP iaoe nr kentelTw'IBr4Ply Equip)Brng a~ 4u -12 tot6: ":u 0,k 6 IA i12:tot06:2 1:tn DPly Eyrdorel84g.1

+12 in t 1O B.arrd ly:EqaipAt6dgelIko600.S

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'l 0to 14 I sn BWlEioivtknI p44 te- n 140. 79 1: isrritStirnols nsortal 14 to ý19*: AdjutAITnwe.

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• Milestone C Oracle Corporatoi alilomia High Speed Rail Classic Schedule Layoot 23 Sep-12 08:3C am I a a 15 1 2017 20 11I IJ141I9I I lq 1 IJJI4fF19 1 I1 11 1_4JH l1:~ .f 14f11"4 .I 1690 Bsmt Fly EquOplBridge Out -22 to -26 1 24-Aug-16 25-Aug-16 1680 Standard 5 DayWorkweek

I: BsrntFEquLpBidigeOt-22to-Re 1700 Bsmt Fly Equip/Bridge In -26 to -30 1 25-Aug-16 26-Aug-16 1690 Standard 5 Day Workweek 1: i ,FWtyEqdougipi ng1: -24to -30S 1710 Bsrt Excavaton

-26 to -30 (L10) 6 26-Aug-16 05-Sep-16 1700 Standard 5 Day Workweek I BantlEvaývýOnioi26no-30 (L10)1720 Bsmt Soil Nair Instal -26 to -30 3 05-Sep-16 08-Sep-16 1710 Standard 5 Day Workweek I BqrlNgrllpstai-6tq-]t 1730 Bsmt Demo Concrete -26 to -30 12 08-Sep-16 26-Sep-16 1720 Standard 5 Day Workweek :i Uisi 60 Denre

-261t,-30 1740 Bsmt Fly Equip/Bridge Out -26 to -30 1 26-Sep-16 27Sep- 16 1730 Standard 5 Day Workweek : Bovrt FtyEquiptiq dge Oct --.Io -3 1750 Shake Out/Pile Drivng Equipment Mob 5 27-Sep-16 04-Oct-16 1740,1060 Standard 5 Day Workweek ,: q Stroke Oot :Stae riorfg Equipment M, 1760 Set Sheet ile Template 5 04-Oct-16 11-Oct-16 1750 Standard 5 Day Workweek I : SetSet PItaTmpte 1770 Drive Sheets 112 EA 20 11-Oct-16 08-Noe-16 1760 Standard 5 Day Workweek '1 trnrseýýSej s11 E 1870 Eocavate for Ring Beam (LL1) 4 09-Nov-16 12-Nov-16 1770 I r(L-L1): 1760 Ring Beam at -34 7 14-Nov-16 22-Nov-16 1870 Standard 5 Day Workweoek C it ea t0 1790 Excavate to -48 (LL2) 11 23-Nov-16 07-Dec-16 1780 Standard 5 Day Workweek 4 Eocivati .8 e (Lo42.2350 AdjustOSTowersto-445 5 08-Dec-16 12-Dec-16 1790 a-1 Adj !dsOS Toweirs t1-44:5 2360 DemoOSWatsto-445 10 13-Dec-16 22-Dec-16 2350 a-1 i pnioO$9Vpltptd4, 2370 Adjust IS Tower 1to -445 4 23-Dec-16 26-Dec-16 2360 a-1 I : Ault!SlTb~e!

tý t,-44ý5 2380 Demo IS Wais 1 to -44 5 10 27-Dec-16 05-Jan-17 2370 a-1 l ermlrtSWallils1to

-445s 2390 AdjustISTower2to-445 4 06-Jan-17 05-Jan-17 2380 a-1 I 2to 5: 2400 DemoIS/OS Wais2to-44.5 9 10-Jan-17 18-Jan-17 2390 A 1 Da" iiSiOSWallk2to 4,6.5 1800 Ring Beam at-48 7 18-Jan-17 27-Jan-17 2400 Standard 5 Day Workweek rg 0em at -1 1610 Excaaste to -61 (1-13) 11 27-Jan-17 13 Feb-17 16800 Standard 5 Day WorkweekB00aet 6 L 2410 AdjustOSTowersto-57 5 14-Feb-17 18-Feb-17 1810 a-1 1 Ajuist OS Towersý t0 -S 2420 DemoOSWallsto-57 10 19-Feb-17 28-Feb-17 2410 a-1 ,i PDemoOSWalIa toV5 2430 Adjust IS Tower lto-57 4 01-Mar-17 04-Mar-1 7 2420 a-I M. i :Adjist IS Tower 1 to457 2440 Demo IS Wis 1 to-57 10 05-Mar-17 14-Mar-17 2430 a-I [)etrrp. ltOIs prin y5?2450 AdjustlSTower2to-57 4 15-Mar-17 18-Mar-17 2440 a-1AdjudtlS Tlr 210 2460 Demo IS/OSWais2to-57 9 19-Mar-17 27-Mar-17 2450 a-. O!1 Wals2Io: 1820 Ring Beamat-61 7 27-Mar-17 05-Apr-17 2460 Standard 5 Day Workweek i q q iN R Beim at-64 1830 Eo ate to -73 (LL4) 11 05-Apr-17 20-Apr-17 1820 St woarad 5 D yVWV.kweek

' Bcavae tol-73 1 (LLO).2470 Remove OS Towers 5 21-Apr-17 25-Apr-17 1830 a-1i ...I O.owvry 2480 DemoOSWaesto-73 10 26-Apr-17 05-May-17 2470 a-i I DI mDboOS Walato,-2490 Remove IS Tower 1 4 06-May-17 09-May-17 2480 a-1i I RemoveISTower 1 2500 Demo IS Wals to -73 10 10-May-17 19-May 17 2490 a-i ..*:Qerro hasItol 2510 Remo-eISTower2 4 20-May-17 23-May-17 2500 a-1i 1:. !!

2520 DemolSIOSWaeis2to

-73 9 24-May-17 01-Jun-17 2510 a-1 i ...Opeo 1840 Ring Beam at -73 7 01-Juan-17 12 Juoe17 2520 Standard 5 Day Workweek p BolinBat-73 1850 Excavateto-80(LLS) 11 12-Jun-17 27-Juoe17 1840 Standard 5 Day Workweek !l Emvalteto, -,0(1910 DemoCaisson Concreteto-80 29 27-Jun-17 07-Aug-17 1850 Standard 5 Day Workweek i Dem o r Ca,', 1935 Remov Spoil Management Area 20 26-Jan-17 17-Jul-17 1950 0; Remnove Spoil M 1945 P00 Clearance of Sorls 10 08-Aug-17 17-Aug-17 1910 a-1 t r leg 1930 Backfillto

-73 8 17-Aug-17 29-Aug-17 1910.1945 Standard 5 Day Workweek :i BrckItd-73 1540 Demo Ring Beam at -73 3 29-Aug-17 01-Sep-17 1930 Standard 5 Day Workwee .I Dmo:Rinj 1800 Bacdllllto

-61 8 01-Sep-17 13-Sep-17 1940 Standard 5SDay Workweek~iJ(:

1960 Demo Ring Beam at -61 3 13-Sep-17 18-Sep-17 1950 Standard S Day Workweek ? i De"nhRi 1970 Backfllto

-48 8 18-Sep-17 28-Sep-17 1960 Standard 5DayWorkweek q :cliq tot 1980 Demo Ring Beam at -48 3 28-Sep-17 03-Oct-17 1970 Standard 5DayWorkweek i DemoR: 1990 Baddilllto

-34 8 03-Oct-17 13-Oct-17 1980 Standard 5 Day Workweek lo tacllttto 200 Demo Ring Beam at -34 3 13 Oct-17 18-Oct-17 1990 Standard SDap Workweek e::b mo Actual Work Critical Remaining Work Suvmmary Page 3 of 8 TASK fitter: All Activities Remaining Work *

• Milestone C Oracle Corporatior Zaifornia High Speed Rari Classic Schedule Layout 23-Sep-12 08*3C.=__ -'Z I ._j8 I'-,-13"1M - 13 29 U n1l, l~1+11[A 4nIiii 144'-111'1111 11 11-t111114JlI11 P1~j4-'I111jq1'1 i PI4 14l1-41 I 2010 Pul Sheets 112 EA 8 18-OcG-17 30-Oct-17 2000 Standard 5 Day Workweek 2020 Badritl and Deme Soil Nails -34 to +12 55 30-Oct-17 15-Jan-18 2010 Standard 5 Day Workweek uLrar .

Ne A I -I Pon OSen 11 2040 2G50 20600 21170 LDern 2000 CY, Excanate 2000 CY Pon Piles 195 EA Badcf DeeroblClean 10 25-Dec17 08-Jan-18 40 08-Jan-18 05-Mar-18 20 05-Mar-18 02-Apr-18 5 02-Av-18 08-Aor-18 2010 2040 2050 2060 2020 1935 Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Standard 5 Day Workweek Stadar 5 ay orkeek$laid 29-WW~li ýNoy-IE. PG&E Decomn*Oeoa PG EDeo iisir Mi'I I I I I I I I I I I I I I I I I I I I I-3010 3370 3530 3040 3960 2590 3070 3160 2530 3920 3800 3020 2600 2610 2800 3360 4160 2620 3930 2630 3080 3180 3190 3120 2640 3690 3200 3090 2650 3960 2540 3540 3130 4140 2660 4180 2550 VWlie Garery equipment removal -Phase 1 LRW Bldg Equip/Pipe Removal Phase I Offgas Tunnel Equip Removal Modify PEG roorninstal RFBAHU Relocate Freline Reactor Vessel internals Removal Perform instrument Air Mods Remove lntermnodals/EquOplTrailers Unit 1,2 Obtain NRC Approval of OOC 3rd Exenmption Remove unit 3 Intake Lines at New 60KV Yar Operatons RFBAHU Vent Mods Build Isolation Wall Remove Concrete Blodk Clean-up Heat Exchangers Supression Chambers (Ring Headers and D(Cut Wan opening in RDTVauo Erect Tent at LFO Site to Support Waste Pkg (-24) Elev Remove Components FSS New Switchyard During Excavation

(-34) Elev Remove Components Turn Over Bldg to Contractor Turn Oxer Unit 1,2 Area to Contractor Unit 1,2 Slab Prep Grading for Drain Turbine Bldg Concrete Scabbing (-44) Elev Remove Components Offgas Tunnel Equip Removal North th LRW Remove Above Grade Systems for Oly Wate Turbine Bldg Open Air Derno Survey (-54) ELav Remove Components Turbine Bldg Vent Mods Drain Reactor Vessel into SFP and Apply FPxn Remove Item from Stack Turbine Bldg Demo Phase I el. 12 Operation of GWTS Shutdown Heat Exchangers Rm (-14) -Rem Identify Onsde Clean Backdil Remove CRDMs from Bottom Vessel 175 02-Jan-12A 25-Jun-12A I 29-Feb-12A 18-Dec-12A 1 01-Mar-12A 30-Aog-12A 116 01-Mar-12A 25-Jun-12A 79 13-Mar-12A 23-Apr-13 1 26-Mar-12A 15-Nov-12A 65 10-Apr-12A 14-Jun-12A 11 13-Apr-12A 24-Apr-12A 1 02-May-12A 01Nowl2A 58 22-Mayl12A 19Jul-12A 11 15-Jun-12A 25-Jun-12A 28 26-Jun-12A 24-Jul-12A 1 02-Ju1-12A 02-Jul-12A 1 02-Jul-12 A 15-Aug-12A 1 02-Jul-12A 31-Dec-13A 1 02-Jul-12A 24-Ju-12A 57 02-Ju1-12A 28-Ang-12A 1 03-Ju1-12 A 31-Juo-12A 92 23-Jul-12 A 22-Oct-12A 1 01-Aug-12A 30-Aog-12A 1 09-Aag-12A 09-Aug-12A 1 09-Aog-12A 09-Aug-12A 25 10-Aog-12A 03-Sep-12A 80 13-Ang-12A 31-Oct-12A 1 03-Sep-12A 27-Sep-12A 32 03-Sep-12A 04-Oct-12A 14 04-Sep-12A 17-Sep-12A 53 17-Sep-12A 08-Nou-12A 1 01-Gct-12A 320 .r-12A 28 01-Non-t2A 28-NOV-12A 1 195Nov 12A 15-Jan-13A 1 295Non12A 28PFeb-13A 90 29-Nov-12A 26-Feb*-13A 1092 29-Nov-12A 25-Nov-15A 1 27-Dec-12A 23-Jan-13A 58 02-Jan-13A 28-Feb-13A I 16-Jan-13A 19 Mar-13A a-1 rupirmn, removay Plrpo 1i a-1 LR Bld1 E*lp/Pipe Phase I a-1 G 1nel Eqip Renoxat 7 a-1 amnisfltaRFPBAHU:

a-1 i Relocate:FIrPrte a-i ctor Vessel loterpalsRprtonal a-1 rtAir Molts a-i appquopr/Trreiers UnW 2: a-1 in NRC Approval of 3-rd Exemppton Request a-1 t 3 bIlnke Lioet at Now 60KV Yard Area a-1 ; A'-O U Vrit Mods a-1 0)6W01 a-1 crete Block a-1 eat Podrenger.

a-i :Slpre~slon Chamb"erS IRIng Hoadors and Droncotrner)

NorhISouth a-i eprrgrrtiDl/psD' .aut a Itat:LFO Sdtt SdpPrort aote'P,.a-I e.nton C.,prt ~rprets i a-I SWdntnyard Guorng Exaavation a-1 Rartnove o Nmporents a-1 Bldg to CoirercloN a-1 Uni 1.2 AeatoCnridrdoi a-1 Sl.b P.rep Grading tsr Dram a-l ire Bdg Concetle Siabbilng a-1 lEW Ramove:Compenprts a-i TvenmlEquip Removal North lb LFWr Big a-1 Abd Gla0e Srsteln fr:Oity:Water.

a-1 r~ev Rnroye C"As a-1 rhire Bd Ven Mde a-1 6r pi Reactor \easol irte $OP adApply Friatrie a-1 ! iif, a-1 Sthrtddwn Heat EakE anorslRnr(-d14)

Remrrbv aRxmaikng:Cbmponenmts

'a-I jdpirify'pyesitleaornicn N-00 a-i1 eoeCDsfomBfvr'lse 1 Actual Work 1 Crtrcal Remarning Work .mlll Summary Page4 of8 0ASK lfter All Activities Remaining Work *

• Milestone/

Oracle Corporahor California High Speed Rail Classic Schedule Layout 23-Sep-12 08:31 ,dK IDt Nam ZZ _".T La 2015...,m 2014 1 016 l0 1 F c"11h111 IiiflJ 11 114J 11 119411t 11 IJIJIA1I1I1,1JI1 I 2750 2080 2260 3810 3700 3030 3210 3780 3550 3820 2730 2090 2560 2760 3150 3830 3560 3580 3220 3590 3850 2570 2670 2680 2690 2100 2820 2770 3230 3860 3600 2110 2580 2700 2740 2830 3610 3790 2840 2780 3240 2120 3620 2850 2930 3870 3890 (-24) Elev Remove Components RPV Relate, Segment RPV Internals in Spent Fuel Pool LRW Bldg Equip/Pipe Removal Phase 2 Hot Machine Shop Cal Equip Removal Ofigas Tunnel Grout FIN Tunnel North to LRV\aMee Galery equipment removal -Phase 2 Partial Remove Unit 2 Pad and Timber pile Offigas Tunnel Equip Removal So. RFB and 'r Grout Embedded Pipe Inside Stack Hot Machine Shop Equipment Cut Control Rod Blades ES to Demob RPV Internals Equip Airgap 66 Nozzles Below Vessel (-34) Elev Remove Components RPV Relate Remove Denmn Fiters in Dernin Room Characterize and Grout HMS Embedded FSS Stack Embedded Pipe to Remain Stack Dame to el. 12 Unit 1,2 Condensate Pump Casings SAS Bldg Demo to el. 12 Hot Machine Shop Concrete Scabbing Remove Decon Facilty Decon/Remove Laydown/Cask Wash Down DecornRemove New Fuel Storage/Fuel Pool Decon/Remove Cask Shipping Area Remove Decon Faciity Emergency Condenser Removal ( 44) Elev Rmovco Compncnis Relateo Unit 1,2 Oily Waste Sumps, Cond Pits, Pipe Hot Machine Shop Deiposition Survey Demo SAS Bldg to el 9 Build RV Containment Faciity Build RV Containment Faility Survey/Apply Fixatives Emergency Removal Pre-Clean SFP Offgas Tunnel Decontarmination Of(gas Tunnel Decontarnination So. RFB and Build SFP Containment

(-54) Elev Remove Components RPV Relate-Soil Remediatoen and Backfill unit 2 Removal Vessel Segmentation Backfill SAS Bldg renovalArea Drain SFP and Apply Fixative to Liner CDP Reactor Caisson Removal CCC Deciaio Hot Machine Shop Pit Casing Demo to el 9 Unit 3 IntakelDischarge Line Removal for TB 1 24-Jan-13A 26 04-Feb-13A 191 04-Feb-13A 25 04-Feb-13A 53 25-Feb-13A 273 27-Feb-13A 58 27-Feb-13A 126 27-Feb-13A 1 04-Mar-13A 25 04-Mar-13A 1 11-Mar-13A 41 12-Mar-13 1 20-Mar-13A 1 26-Mar-13A 60 01-Apr-13A 30 01-Apr,-13A 1 02-Apr-13A 1 02-Apr-13A 29 29-Apr-13A 1 01-May-13A 30 01-May-13A 1 08-May-13A 1 08-May-13A 1 08-May-13A 1 08-May-13A 22 08-May-13 1 13-May-13A 1 23,Muy-13A 59 28-May-13A 11 03-Jun-13 A 62 06-Jun-13A 43 07-Jun-13 1 10-Jun-13 A 1 11-Jun-13A 1 11-Jun-13A 1 11-Jun-13A 63 03-Jul-13A 91 03-Ju -13 A 1 11-Jul-13A 1 24-Jul-13A 29 29-Jul-13A 171 07-Aug-13 29 07-Aug-13A 1 14-Aug-13A 1 20-Aug-13A 58 01-Oct-13A 25-Mar-13 A 11-Mar-13 28Oct- 13 28-Feb-13 A 18-Apr-13A 26-Nov-13A 25-Apr-13A 02-Jul-13A 01-Apr-13A 28-Mar-13A 02-May-13 A 07-May-13 18-Jun-13A 22-May-13A 30-May-13A 30-Apr-13A 30-Apr-13A 30-Apr,- 3A 27-May-13A 05-Jun-13A 30-May-13A 06-Jun-13 A 05-Jun-13 A 05-Jun-1 3 A 05-Jun-13A 06-Jun-13 10-Jun-13 A 23-Jul-1I A 25-Jui-13 A 13-Jun- 13 A 06-Aug-13 A 06-Aug-13 06-Aug-13 A 24-Jun-13 A 09-Jul-13 A 10-Jul-13A 03-Sep-13 A 01-Oct-13A 13-Aug-13A 22-Oct-13A 26-Aug-13 A 02-Apr-14 04-Sep-13A 07-Jan-14 A 01-Oct-13A 27-Nov-13A a-i Standard 5 Day Workweek Standard 5 Day Workweek a-1 a-1 a-1 a-i a-1 a-1 a-I a-I 2080 Standard 5 Day Workweek a-1 a-i a-i a.-a-I a-1 a-1 a-1 a-1 a-1 a-i a-1 a-1 2090 Standard 5 Day Workweek a-1 a-1 a-1 a-1 a-1 2100 Standard 5 Day Workweek a-1 a-i a-1 a-1 a-I a-1 a-1 a-1 a-1 2110 Standard 5 Day Workweek a-i a-1 a-1 a-I li (-34) len Rer CymponleoyRPY Relat ebred I ,egretRPVlnterrdakni F lRW Mgi E9rdip),i~pe R'etniteal Phabe;2: ,Ifidg FI Tlunhel Nolbtit L'RW4Bkdgl D gaM itS B ',and Ya 0 Gyopt Errhe~dde Pipp Iwui~e Olipol Cut Cyntrint odc Btaders ES ! E8 I eto Demo ib RPV l n,:terriral Eqi .......1 i"::'rggp, 66 Nozzled BelrbwVeus

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All Activities Remaining Work *

• Milestone 7 Oracle Corporabo Calilomia High Speed Rail I Classic Schedule Layout I 23-Sep-12 08:3(F t14 1 1 4111 I9IIIII l11 IJ111 11 1,AI I 2710 2790 3460 2270 2940 3270 3840 2280 3280 4110 2290 2720 2860 4250 3380 3430 3880 2810 2870 2910 2880 3300 4260 3900 3290 3330 3340 2890 3310 3320 3350 2130 2920 2140 4120 2950 2300 3470 3480 3250 3630 3640 3660 3670 3680 3710 3730 (+12) Misc Equip and Systems (-66) Elav Remove Components RPV Relatet Active Radwaste Discharge Line Removal LRW Concrete Scabbing Low Level Storage Deconta-mination LLW Bldg Disposion Survey FSS Hot Machine Shop Removal Area LRW Buiding Disposition Survey LLW Storaage Bldg Removal Below Grade Intake Canal Rernediation LRW Building Demolition to +12 Charact./Grout RB embedded pipe/penetratk TB Drain Tank (TBDT) Floor Drain Pump Refueing Building Concrete Scabbing LRW HVAC Mods FSS Active Radwaste Discharge Line Remov Bacdill HMS RemovalArea Remove Supression Chamber Liner Remove SFP Bridge Crane Remove SFP Liner Survey SFP Bridge Crane and Apply Fabures High Level Storage Vaul Removal Construct Shlrry WanAround RFB Soil Renaedithon and backfil South End FSS HPgh Level Storage Vaul Removal Area Remove Upper Yard Soils 1 Deep Remove Yard Drain Piping Reacd., Equip Drain Tank -FSS and GroutHigh Level Storage VWul RemovalAre FSS Upper YardExc'avaton Area Bakdfil Upper Yard Area Asbestos Removal from Pipe/Equip in Drywel SFP Shave Concrete WalllFlor Reactor Vessel Cavity (Drywel Systems Rem Discharge Canal -SP, Reined, Char. Dsch St Disposhion Survey ot RFBAfBer Scabbing Cut 480V Cold and Dark Trench at Slurry We Radwaste Tank Removal Abandoned Radwaste Line Removal Remove UnLi 1 pad and Remainmig Unit 2 Pa Offgas Tunnel Demolition Demo Stack Slab to el. 9 North Yard Elect Ductbank Removal North Yard Fire Protection Line Removal Notth Yard Storm Drain Removal Remove Offgas Tunnel North to LRW Bldg New Offgas Vaut Demo/Tunnel to el. 9 1 23-Oct-13A 1 23-Oct-13A 1 29-Oct-13A 24 29-Oct-13 28 29-Oct-13A 1 26-No13A 29 28-Nov-13A 8 02-Dec-13 I 03-Dec-13A 182 10-Dec-13A 24 12-Dec-13 1 24-Dec-13A 1 24-Dec-13A 183 24-Dec-13A 1 26-Decn13A 1 30-Dec-13A 29 30-Dec-13A 1 01-Jan-14A 1 08-Jan-14A 1 S0-Jan-14A 1 15-Jan-14A 1 15-Jan-14A 180 16-Jan-14A 23 28-Jan-14A 1 13-Feb-14A 1 13-Feb-14A 1 13-Feb-14A 1 20-Feb-14 A 1 17-Mar-14A 1 17-Mar-14A 1 31-Mar-14A 43 03-Apr-14 1 14-May-14A 80 03-Jun-14 275 10-Jun-14A 1 25-Jun-14A 106 01-Jul-i4A I 15-Jul-i4A 1 15-Jul-I4A 58 15-Jul-14A 59 15-Jul-14A 59 15-Jul-14A 29 15-Jul-14A 29 15-Jul-14A 29 15-Jul-14A 58 15-JuIl-14A 59 15-Jul-14A 23-Dec-13A 19-Feb-14A 26-Dec-13A 29-Nov-13 25-Nov-13 A 02-Dec-13 A 26-Dec-13A 11-Dec-13 16-Dec-13A 09-Jun-14A 14-Jan-14 24-Apr-14A 19-Feb-14A 24-Jun-14A 22-Jan-14 A 27-Jan-14A 27-Jan-14 A 08-May-14A 14-Jan-14A 13-May-14A 28-Jan- 14 A 12-Feb-14A 14-Jul-14A 19-Feb-14A 13-Mar-14A 13-Mar-14A 13-Mar-14A 25-Mar-14A 14-Apr-14A 27-Mar-14A 07-Apr-14A 02-Jun-14 11-Aug-14A 22-Sep-14 11-Mar-15A 23-Jul-14 A 14-Jul-14A 11-Sep-14A 11-Sep-14A 10-Sep-14A 11-Sep-14A 11-Sep-14A 12-Aug-14A 12-Aug-14A 12-Aug14A 10-Sep-14A 11-Sep-14A a-I a-1 a-i 2260 Standard 5 Day Workweek a-I a-1 a-1 2270 Standard 5 Day Workweek a.-a-1 2280 Standard 5 Day Workweek a-1 a-1 a-1 a-i a-i a-1 a-i a-1 a-1 a-1 a-1 a-1 a-1 a-I a-1 a-1 a-1 a-i 2128 StandardS5 Day Workwveek a-1 2130 Standard 5 Day Workweek a-1 a-i Standard 5 Day Workweek a-1 a-1 a-1 a-1 a-1 a-l a-1 a-i.-I a-1= :m (+12) Misc Equipand Si rto : ! : : !::: :!: : : i: :: : :: : : !::: (-o 466>Lý Eel Reeh-6 C6riP nerrts: RIPY tated Acrive cr lhihu Ihi Removal: Lvi s L -a n ~ ii! ,iii iiiiiiiiiii i9 LLEW ddg bi Dp .nSus .--O PI5 'SHotiMa e Shop Area- -: i BLRW:Blalrgý BlpdsigbO Suvey' : i PIPU Ilntvake gahg Ftepv efioh ir r*J LRW Eiui~hg DeR6-imt!on to02 ii ip Ch"a:aýa , ,. , ,. ., , , .. .. ......M:TB Drgin Tank (TBDT) Floor Dribirl Purmp: ::tCnsterg oy~aaersuadRFB

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IPPPP Dwisharge Caýal -SP, Rente, Chat- D"l Str: Ren*ft DlipysS~ SurveyI ot RFQAftnr $casbing i :: .:, ,i ,' i ,:= ýiP knSa~ f A r e bn 9 :: cp b :: :. ..: S Cqut 48qV Cold ind ParI Trench at hSkl ie S l: RedWaste Tank ReOriovda A* P~ndudRecive ste Lin Rt incpio Retrrdim4pal d1 Revanla 1iirlg:Uit 2:Pid QC~gasTuInrtetl~emoiirtin Deem 9.. .dSl~ .v e.9 .H*NaGth Yard Elect Duttbamk fRetolvai*Norsi Yardl ri~e Pio~e-*n iqoJe. F~mqvgl Remove Tr North ti LRW, Bldg 1 Nes wdt r lenma°el Ia e l. a Actual Work Crital Remaining Work Summary Page 6 ot B ASK ilter Alt Achivoes Remainin9 Work *

• Milestone i Oracle Corporatior

-alifornia High Speed Rail Classic Schedule Layout 23-Sep-12 08.30 Azf DAtvt an* :rk 201 290O 3520 3570 3490 3170 3760 3400 3440 3450 3140 3720 3800 2150 3390 3260 2160 3410 3750 2170 4040 40980 4090 4130 2180 2190 4070 2200 4100 2210 3970 3980 3990 4050 4060 3910 2220 4030 3940 2960 2230 400 4150 4210 2240 2250 2990 3000 Dispositon Survey of SFP After Shave Concr Plant Exhaust Fan FSS Stack & SAS Bldg RemovalArea Backt9flAchve Radwaste Discharge Line FSS UL and U2 Site North Yard Drainage System Removal North Yard Soil Remediation FSS Radwaste Tank Discharge Line Remova FSSAbandoned Radwaste Disch Line Remo, Turbine Bldg Demo Phase 2 FSS New Offgas VauJt/StaclfSAS RenovalA Offga Tunnel Demo So. RFB and Yard Remove Asbestos from Drywell at Liner Pene FSS North Yard ExcavationArea Banckll UL and U2 Site Remove Drywael Liner Backfill North Yard to +12 FSS North Yard Drainage System Unit 3 Remove Activated Concrete North Yard Drainage Removal U1,2 Unit 3 Discharge Line Downstream ofAnchor Unitl.2 Discharge Lines Dowrntream ofAnch Charaderze Survey of Bay Outside Disc Can Remove Crane Refueing Building Removal to +12 FSS UL,223 Discharge Lines RemovalArea Remove RFB +12 Stab at Crane Bay Backfill U1,2,3 Discharge Lines RemovalAreu SFP Removal Unit I Intake Line Removal from intake Strucl Unit 2 Intake Line Removal from intake Strucl Unit 3 Intake Line Removal from 601k yrad to Unit 1 Discharge Line removalAnchor block " Unid 2 Discharge Line removalAnchor Block Oily Water Separator Removal Perform Soil Remediataon FSS U1,2 Discharge Lines Removal toAncho FSS Unit 1,2,3 Intake Line RemovalArea FSS Reactor Concrete Caisson Reactor Caisson Concrete Backfill Backfill U1,2,3 ines removal area Removal of GWTS CDP Developed Areas Restored Remove RFB +12 Slab Spent Fuel Pool Backfill Start Demo of Reactor Caisson/SFP Mileston Remove Debris from SFP Well Demotion I 12-Aug-14A 09-Sep-14A I 12-Aag-14A 1-Sep-14A 1 13-Aag-14A 10-Sep-14A 1 08-Sep-14A 06-Oct-14A 29 11-Sep-14A 09-Oct-14A 62 l1-Sep14A

!1 Nov 14A 1 12-Sep-14A S6-Oct-14A 1 15-Sep-14A 13-Oct-14A 1 15-Sep-14A 13-Oct-14A 88 15-Sep-14" 11-Dec-14 29 15-Sep-14A 13-Oct-14A 88 15-Sep-14A 11-Dec-14A 24 23-Sep-14 24-Oct-14 1 07-Oct-14A 04-No-14iA 29 13-Oct-14A 10-Nov-14A 110 27Ocd-14 27-Mar-15 1 05-Nov-14A 03-Den-14A 29 12-Nov-14A 10-Dec-14A 69 19-Jan-15 23-Apr-15 58 20-Jan-15A 18-Mar15A 92 12-Mar-i5A 11-Juan15A 92 12-Mar-15A 11-Jun-15A 29 12-Mar-15A 09-Apr-15A 18 24-Apr-15 19-May-15 34 20-May-15 SB-Jul-15 29 15-Jun-15A 13-Ju1-15A 17 07-Jul-15 29-Jul-15 29 14-Jul-15A 11-Aug-15A 44 30-Jul-15 29-Sep-15 58 12-Aug-15A 08-Oct-15A 58 12-Aug-15A 08-Oct-15A 62 12-Aug15A 12-Oct-15A 58 12 Aug15A 098Oct-15A 58 12-Aug-15A 098-Oct-15A 58 21-Sep-15A 17-Nov-15A 17 30-Sep-15 22-Oct-15 29 12-Oat-15A 09-Non-15A 28 13-Oct-15A 09-Nov-15A I 21-Oat-15A 19-Jan-16A 35 23-Oct-15 10-Dec-15 28 10-Nov-15A 07-Den-15A 63 26-NoV-15A 27-Jan16A 92 30-Nov-15A 29-Feb-16A 34 11-Dec-15 27-Jan-16 20 28-Jan-1 24-Feb-16 0 04-Feb16BA 1 04-Feb-16A 07-Mar-16A a-1 a-1 a-1 a-1 a-1 a-1 2140 Standard 5 Day Workweek a-1 a-1 2150 Standard 5 Day Workweek a-1 a-1 2160 Standard 5 Day Workweek a-1 a-1 a-1 a-1 2170 Standard 5 Day Workweek 2180 Standard 5 Day Workweek a-1: :is 05:dp Si fSIFey of SIF After: Shave toncrete: IN Si Stanack & SAS Bdq 'Re~ iir eAL !0 BPac) rlve Rttadlvaltq Oi.rgutag 1P FSS Ljardji2:SRk6 North Yard Drainage Systemttemon

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• Milestone C Oracle Corporatior attornla High Speed Rail Classic Schedule Layout 23-Sep-12 08:3C Calen.lc, 2013 1 2 DI, 1 / 018 1 211117 12018 IF' ` .I ..lllt1J~ .q .J~'~l1ll II 114AI I JJI- =l 1!

I 3500 Baddli Radwaste Tank Line RemovalArea 1 04-Feb-16A 07-Mar-16A a Baci ll Rarlate Tanlk Line t ,agbr 3510 BaddfilAbandoned Radwaste Disch Line re; 1 04-Feb-16A 07-Maw-16A a- I BacdlolAbanadned R0a0wetDindsLiae Aea 3100 Turbine Bldg FSS and Backill 56 04-Feb-16' 30-Mar-16 a-1 Torfi ,n04g:: F0 S nd Baý t : 3650 Baddcll Stac*kSlabArea 33 04-Feb-16A 07-Mar-16A a-i N B tfi* , c1abr i 3740 Backldl New OffgasVaut RemovalArea 33 04-Feb-ISA 07-Mar-16A a-1 Bdd, NeOwaffýak Vault RyboRalArda 3770 Backfill North Yard Drainage SystemnArea 33 04-Feb-16A 07-Mar-16A e i i B6edaNMothatd DreinogoSysten/rgo:

4010 South Yard Drainage System Removal 92 04-Feb-16A 05-May-16A a-1 So1hYb4 , DrbiiageSnernrReroval 2310 Site Restoration 64 25-Feb-16 24-May-16 2250 Standard 5 Day Workweek : : :-:: : :Site Restoration 2980 FSSSFPRernovalbrea 1 07-Mar-16A 04-May-16A a-1 !F$! 8Ft irraIAnep 2970 FSS Spent Fuel Pool RenmoalArea 59 07-Mar-16A 04-May-16A a- 5 F Spk ntS " ouPao!Rethnl.ra 4170 Remove Tent fom LFO Site 8 07-Mar-16A 14-Mar-16A a-1 ::i Tent nonLFOQite, 4220 RUBBTentFoundationRemrroval 30 07-Mar-16A 05-Apr-16A a-1 i RUPB TentFoundan Renrvel 4240 FSS SFP 59 07-Mar-16A 04-May-16A a-, FSS SFP Ronio"alAte; 4190 FSS LFOSite 59 14-Mar-16A 11-May-16A a-1 ...lF Sie 3110 TB Final Status Survey 30 30-Mar-16' 28-Apr-16 a-1 1 TB Final Statii, Soody 3950 FSS South Yard DrainageArea 33 05-May-16A 06-Jun-16A a-1 FS0 South FaradID!ainaglerea

4200 LFO BermArea Backfill 34 11-May-16A 13-Jun-16A a- rmArea'Bhcflill 4020 Bacdilt South Yard DrainageArea 30 06-Jun-16A 05-Jul-16 A a-1 I U Yaird: D nr gArgaa L 3420 LRW Bldg Slab Remo-e to 9 1 09-Ang-16A 10-Oct-16A a-1 m! Loyet 0 4230 Site Restoration 113 09-Ang-16A 29-Nov-16 A a-1 t :-7 f7 Actual Work Critical Remaining Work ,m Summary Page 8 of 8 [ASK filter All Actibies Remaninig Work

• Milestone 0 Oracle Corporathor KOKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX D FINAL GRADING SPECIFICATION Page 171

-QOKlewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Final Site Grading Snecification Backfill for the caisson demolition will consist of import fill and on-site excavated soil. Fill material, imported or existing on-site material, shall meet the screening levels and/or requirements set forth by the DTSC, RCRA, CHSSL, and the NRC. An agency approved set of requirements will be provided by PG&E when it is available.

Radiological screening shall be performed by PG&E and environmental screening shall be performed by PG&E approved laboratory.

For on-site soils that are determined to be environmentally and radiologically suitable for use as backfill and for import soil, the following general specifications should apply: Backfill Below Elev. -10 ft* Free of debris, organic matter, glass, trash, and unsuitable materials;

• Free of broken concrete and asphalt;* Free of rocks greater than 8 inches in any dimension;

• Shall meet the SW classification in accordance with USCS with a fines content less than 10%;* Have gradation curves that lie within the hatched zone in the figure below; and,* Shall be placed in a uniform manner free of voids and in a manner that limits segregation of material.3Mmn No.4:aeuiw No. 1 No. 100 No. 40 No. 200 Su.e' iNUMt*r 100 90 80 70 50"40 30 20 10 0 111111. H ill I 1 111 1 1 1 1 1 111V Hill I 1 111 1 1 11V Hill I I III H ill I I Hill I I N I Hill 1 11 YX : Hill I 9 A\1 U111 I 111111 t oil 100 10 0.1 0-01 0.001 1 Grain Size (mm)Backfill Above Elev. -10 ft* Free of debris, organic matter, glass, trash, and unsuitable materials;

• Free of broken concrete and asphalt, Page 172

-OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report* Free of rocks greater than 8 inches in any dimension;" Nesting of cobbles within the fill shall not be allowed;* Open graded or gap graded aggregates shall not be used;* Plasticity index less than 15 (ASTM D-4318);* Liquid limit less than 40 (ASTM D-4318);* Fines content less than 30%;* Non-expansive; and,* Have gradation curves that lie within the hatched zone in the figure below.3ANia )L 4 No. 100 100 90 80 70 0 60 in 50 0. 40 30 20 10 0 314nL No 4 M& 140-10 No. 40 No. 2W REL I I IN I I I PIT Hill I I I Hill I I Hill I I Hill N lull Itt f M "ýý4 V:N9II 100 10 1 0.1 0.01 0.001 Grain Size (mm)Lift thickness will be dependent on the compaction equipment used, but should not exceed three (3)feet. For proposed lift thicknesses exceeding one (1) foot, the contractor shall submit a "method" compaction specification that shall incorporate methods for verifying the compaction of the entire lift.Backfill shall be compacted to 95% of the maximum dry density and within 3% of the optimum moisture content as determined by the standard proctor (ASTM D698). Alternate compaction requirements such as relative density or post backfill in-situ testing may be incorporated into the contractor's backfill method. Alternate methods and method specifications shall be developed and performed at the contractor's expense and approved by PG&E.The use of soil mixing should be considered to reduce the fines content and/or plasticity index of on-site excavated clay. This could be accomplished with approved on-site soil, imported fill soil, lime, fly ash, or cement (slag or Portland).

Additional laboratory testing shall be performed to determine if soil mixing is appropriate and the required mix proportions.

Page 173 HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX E SEISMIC DESIGN CRITERIA DIRECTIVE Page 175 n Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Nick.Gura Sent: To: Co:

Subject:

Page. William <WDP7Qjge.com>.

Mtonday, May 21, 2012 1.V8 PM ick.Gura Sun, Joseph; Wooddell.

Kathlyn; Ferre, Kent S; Abrahamaou Norman; Klimczak, Richard;nha3@eartlttAnel RE: Seismic Design @ Humboldt Bay Mik Sorry fo the delay. We finalty gal to disruss the issue with Norm this morning. He noles that the sile i in a very high seismic area and recoded G.Sg in 1994. He ecaommends for the design criteha to use the 50% in 91 yrs. Tihis translates to G.5g .se. table in Joseph.s email below).If you have questions please call Bill oell 916-212-3627 From: Sun, Joseph Sent: Friday, May 18, 2012 12A9 PM To: Wooddell Kathryn; z Fen-e, Kent:S; Abrahamson, Norman; Kfimczak, Richrd; Page. WilfIam Subject RE Seismic Design @ Bay All Based on the attached Table from HBPP ISFSI PAR, here are various risk levels: Risk Exposure 10%in SO years 30% in 30 years 50% In 50 years S% In S years 10%CIn S years 2% in 2 years 5% in 2 years Return Period PGA 475years t0.%g 8S years -0A8g 72 years -0.4Sg 97 years "-tSi1g 47 years -0.41g 98 years -.Sig 39 years -&38g For temporary coffer dam design, the design is usually based on 25-year to S0-ear flood. However, flooding the coffer dam usually has flnardal ifmpact rather than Ufe safety risk. HBPP construction duration Is 2 yeaas plus It Is a contaminated site, I suggest that we accept a #A to O.Sg for design with a return periods of 513 to 100 years. Need Norm'¶s Input.Joseph Page 176

-O*Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report NIck.Gura From: Sun, Joseph Sent: Wednesday, May 23, 2012 11 00 AM To: MckcGura; Page. William Cc: carlz@coopercm.com:

DrucePallterson; dreggett@esengineerfng.com; Keith.Maltecheck; Wooddll. Kathryn; Abrahamnson, Norman: naa32earthlhnknaI; Klimczak, Richard Subjact RE: HBPP -Sesimic design criteria Aflachments:

RE: Seismic Design @ Humboldt Bay: RE: Seismic Design @ Humboldt Bay Nick, Based on our phone discussion yesterday, I understand that you need the response spectra for the design of HBPP internal temporary bracing support for caisson removal- The information you requested is already shown in the Table you provided on May 18, 2012 or Table 2-5-18 from the H-1PP ISFSG FSAR (attached).

In consultation with Norm Abrahamson, Bill Page sent you an e-mail on May 21, 2012 (attached) and suggested that a design PGA of O.Sg be used which roughly corresponds to the 100-year event. The 100-year response spectra can be developed by plotting the Sd'column against the V1 column from Table 2-6-18. You can treat the 0.01 sec spectral acceleration as the PGA (peak ground acceleration).

If you have any questions, please free feel to call me.Joseph From: -ic-.Gura m Fmaio*:Nick.Guralkiewitcpnil Sent: Tuesday, May 22, 201.2 7:12 AN To: Page, William; Sun, Joseph Cc carizccgopercm.am:

1Bruc.Patmcn~kiewitccn d aeggethaesenrineerina~ca

Keith.MatbLcheckdbwit.on

Subject:

HBPP -Sesirnic desin criteria Bill, Could you provide the graph for seismic acceleration vs time for the 50D6 in 50 years?We are looking for the 0.2 sec seismic acceleration, which is used for calculating lateral loads on earth retaining structures.

Infirsst .gwe "up NICHOLAS GURA. P.FE oesign Engneer KIEWIT ERIHIIEERING CO.Page 177 HUMBOLDT BAY ISFSI FSAR UPDATE TABLE 2,6-18 EQUAL HAZARD SPECTRA (g) FOR THE FAULT NORMAL COMPONENT FOR SOIL SAFE CONDITIONS.

Y II n .. .. .Period Ssec)1 Yr 25 yr 50 yr n m, 100 yr 500 yr 11.0O00 yvI2,000 yr 5,000 yr1 10,000oyr VI 03 03'IA.0.-' .4 J. I I--I ani nnrA.9 njiql4RI fl7gL7 I I d37gR tI 7"R-v O0 0.03 0.04 0.3168 0.4175 0.5379 0.8084 0.9032 09829 1.0971 1.1914 L_0,10 0,0076 0.5219 0,6801 0.7940 1,1012 1,95W 1.3389 1.4944 1,6229 0.15 0.0088 0,6578 0.8821 1M 1.528 i 16959 1.8015 1.9487 2.0767.0.20 0.0110 0,.82 1C.0690 ' 2,0493 2,2716 2.151-57 2.8337 3.1006 0.25 0.0104 0.8450 1.1837 1.5217 2.2760 2.6377 2.9280 3.2399 3,4770 0.30 0.0094 0.7644 1.1031 1A4322 2.2161 2A778 2,7427 3.0941 3.3236 0.36 0.0087 0,6846 1.3427 2,1535 2.4478 2,6454 2.8930 3.1113 0.40 0.0082 0I6128 0.8953 1.2384 2,0439 2.2503 2.4775 2.086 2,8719 1.-81 1080= 2.02,6128

____0.50 0006I 0.5380 0.7170 1.0_10 ..8 7 2.1O 2,2800 2,5320 2.7128 0.60 0.00511 0.43 0.654W 0.= 1.7485 I1.9 2.1531 2.4228 2-615 0.80 0.0040 0.3210 0,4837 N0.964 _1.444_ !.8 TiB 2.08 2.25!7 1.00 0.0038 0.2965 0.4469 0.6452 1,3165 1.5507 117382 1.9419 2.1210 1.50 0T0025 0.2000 0.3196 0.4764 '1.0821 1.3129 1,5282 1.8083 2.0373 200 00013s 0.1206 0-1967 0.311- 08237 10551 1.2766 1.578 1.7904 3.0 0.001 04.465 1 0.0783 016 1 0,3358 2 0.8 1.07 57 (A 0~3D i OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX F PERMITS Page 179

-OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Permits for Humboldt Bay Caisson Removal Project Water: The site is under the North Coast Regional Water Quality Control Board (Region 1) and is on Humboldt Bay." Construction General Permit for Storm Water -PGE has an existing permit and will modify for additional construction activity.* Groundwater De-Watering

-PGE to amend SWPPP for GWTS to discharge under Construction General Permit for Storm Water for dewatering

• Groundwater De-Watering

-Contractor to obtain well construction permits.* Compliance with Water Quality Control Plan for Enclosed Bays and Estuaries

-GWTS designed to comply.* Coastal Development Permit -PGE to obtain* Slurry wall construction will need to be reviewed by NCRWQCB; currently, we don't expect that a WDR permit is required, but follow-up meetings with NCRWQCB will be necessary to confirm.Air: The site is under the North Coast Unified Air Quality Management District* Dust -contractor to comply with NCAQMD Rule 104 (Prohibitions).

Contractor will also need a grading permit which may also include a maintenance plan." Title V -PGE has a site wide Title V that includes the HBGS operating plant. The NCAQMD considers the HBPP/HBGS site as one site for permitting purposes.

There are some general conditions under the existing Title V permit that apply to the HBPP portion of the site. Diesel -We will need to comply with the Portable Air Toxic Control Measures and Portable Equipment Registration Program (PERP) for diesel powered portable equipment 50hp and greater. Any individual permits required by the contractor would need to be obtained via amending the Title V permit PGEmaintains for the HBGS plant. Therefore, PG&E's preference is to avoid permitted diesel-powered equipment if possible.

All off-road equipment will need to be in compliance with the In-Use Off-Road Heavy Equipment Regulation.

Page 180 OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Hazardous Materials: " Hazardous Materials

-PGE has a Hazardous Materials Business Plan and submits it to the Certified Unified Program Agency (Humboldt County Division of Environmental Health).Contractor to provide hazardous materials inventory information to PGE on a monthly basis and obtain PGE approval before bringing hazardous materials onsite.* Spill Prevention, Control, and Countermeasures Plan (SPCC) -not planning on storing fuel on-site.Sensitive Species* There are restrictions under the existing CDP for work near environmentally sensitive areas.New CDP permit may identify new restrictions relating to noise, etc. during nesting season. PGE will provide biologist for work within environmental sensitive areas, e.g. the construction/operation of the soil stockpile area.* Cultural resources

-Current CDP requires cultural monitoring although enough work has been completed that onsite monitor is not likely to be required during excavation.

However, if artifacts are encountered, the PGE cultural resources monitoring will need to be brought onsite to investigate.

Non-Permit Approvals" Reuse of soil will require approval of DTSC under IMRAW (or final Remedial Action Plan); will likely require coordination with NCRWQCB." Any potential offsite storage of soil will require approval of DTSC in Remedial Action Plan and likely require concurrence by NCRWQCB.Page 181 O@Kiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX G SUBSURFACE FIELD INVESTIGATION REPORT Page 182 Consulting Engineers

& Geologists, Inc.I J 812 West Wabash- Eureka, CA ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: .JPR LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIMETERIDEPTH OF BORING: _&X01 1 8 6 Feet BGS DATE STARTED: 8/24112 DATE COMPLETED:

8/26/12-SAMPLE a!z Z ~ .SOIL DESCRIPTION

z. REMARKS z Wz 0 0 ul _ _ _ __5 12-0 Upper 5' hand augered 17 10 22 SSa-001 Ba-002 SSa-.003 004.SSa-005 Ba-007 007 3 4 6 27

• 15 4 7 10 4 8 e 13 17 19 SILTY SAND, dark gray, medium dense, moist to wet, fine sand, -40% fines Grades to siltylclayey LEAN CLAY, dark yellowish brown, faint mottling, stiff to very stiff, variable sand content (<20%)SILT WITH SAND, dark gray, medium stiff to stiff, moist to wet, low plasticity, fine sand (10-20%), very fine (<1 mm)Interbeds Grades into SANDY SILT, strong brown to dark gray (mottled), medium stiff, moist to wet, low plasticity, 40%fine sand Thin Interbeds (1-2 cm) of SILTY SAND, typ Iron stained 2.5 3.0'0.5 1.5 1.0 1.5'2.5 1.0 2.5-20 SILTY SAND, brown to dark gray (mottled), medium dense, wet, interbedded with SPISM POORLY GRADED SAND WITH SILT, dark yellowish brown (10YR 4/4), medium dense to dense, wet, fine sand, 5-10% fines 32 1i9!(BOIG O Pg"ume Io BORING LOG Page Number 1 of 9 Consulting Engineer 3yu- 812 West Wabash, Eurek6, Ci PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB s & Geologists, Inc.A ph. (707) 441-8856-fax.

(707) 441-8877 BORING LOG LOCATION:

Humboldt Bay Power Plant KB-1 ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: / 186 Feet BGS DATE STARTED: 8/24/12 DATE COMPLETED:

8/26/12 SAMPLE-> FW: .z 0 :3 SOIL DESCRIPTION REMARKS.J _I tw 0in L W c 0 a~ (a, w!0 9C EE ,. r.j Lu ,4 a.0 LU 0 0 , 00 am .'37 42-25 w30 SANDY SiLT, dark bluish gray, medium-stiff, wet, low plasticity, fine sand (40%)SILTY SAND, olive brown (2.5Y 4/3), medium dense, wet, 20-40% fines, fine sand POORLY GRADED SAND WITH SILT, brown (10YR 3M3), medium dense, wet, 5-10% fines, medium sand SILTY SAND, dark yellowish brown (10YR 4/4), medium dense, wet, 30% fines, fine sand, massive I Same, 20-30% fine sand 47 15 POORLY GRADED SAND WITH SILT, dark yellowish brown (10YR 4/4), dense, wet, 10% fines, fine sand Occasional thin (<2%) layer of coarse sand/fine pebble, otherwise massive Gravel disks in shoe (responsible for high blow counts)POORLY GRADED SAND WITH SILT, dark yellowish brown (I0YR 4/4), dense, wet, 10% fines, fine sand ItSILTY GRAVEL WITH SAND, dark yellowish brown, medium dense, wet, gravels to 3", coarse sand POORLY GRADED SAND WITH SILT, dark yellowish brown (10YR 4/4), dense, wet, 10% fines, fine sand 1,4.1-40 52 w Ah as own, medium stiff, wet, interbedda Swith sands BORING LOG Page Number2 of .

Consulting Engineers

& Geologists, Inc.... .. 812 West Wabash,. Eureka, CA Oh. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: 1 186 Feet BGS DATE STARTED: 8/24/12 DATE COMPLETED:

8/26/12 BORING LOG KB-I[Off1-- SAMPLE-z -J 0 M SOIL DESCRIPTION REMARKS 0 aj 12 .2 8 03_ _ _) _ _ _ _ _ _ _ __j_ _ _Iu .U) 8 ~ LC __ _,45 57.-50 62 67 r.55 POORLY GRADED SAND WITH SILT, dark yellowish brown (1OYR 4/4), dense, wet, 10% fines, fine sand Very stiff, Iron stained, sandy interbeds Interbedded SPISM with stiff to very stiff clay, 4-6" max, iron stained sands SILTY SAND, dark brown (7.5YR 3/3), medium dense to dense, wet, -30% fines, interbedded with thin (<1 cm)lenses of clay, fine sand SILTY SAND, dark brown (7.5YR 3/3), medium dense to dense, wet, 15% fines, thin interbeds still present, iron stained at boundaries Interbedded clay/sand

(-1" beds)With gravels, fine, well-rounded, primarily silitlous clasts POORLY GRADED SAND WITH SILT, dark brown (IOYR 3/3), dense, wet, fine to medium well-rounded sand, rare fine gravel Grades Into SILTY SAND, dark yellowish brown, dense, wet, fine to medium, sandwn(YR 4/3), dense, wet,flne to------medium sand, 20-30% fines, Interbeds of coarse sand, 3.0 4.0-60 72 77-65 BORING LOG Page Number 3 of 9 (Consulting Engineers

& Geologists, Inc........ 812 West Wa.ba0sh, Eureka, CA -ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: /1 DRILLING METHOD: Mud Rotary DATE STARTED: 8/24/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

8/26/12 LOGGED BY: JPB 86 Feet BGS BORING LOG KB-1 1/j i L .-_SAMPLE S-, IL E Lu' SOIL DESCRIPTION z.8 REMARKS JI-z CL2 ) -LL U a. uJ.? u n _.-. ..e-J UJI < CL0Oa LU. 0 V) W 0 U(. M C___._6R__

82 87 92-70-75-80 predominately fine Sand coarsens at 72' (well graded) in alternating beds SILTY SAND, dark olive brown (2.5YR 3/3), dense, wet, fine to medium sand, well rounded, -20% fines, rare fine gravel POORLY GRADED SAND WITH SILT, dark olive brown (2.5YR 3/3), massive, dense, wet, 10-15% fines, fine sand POORLY GRADED SAND WITH SILT, dark olive brown (2.5YR 3/3), massive, dense, wet, 10-15% fines, fine to coarse sand, well roundedlight gray, wet,5% san 5.6 97 85 BORING LOG Page Number 4 of 9

.. -Consulting Engineers

& Geologists, Inc... .812WestWabash, Eureka, CA ph. (707) 441-8855 fax.(707)441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING:___

/186 Feet BGS DATE STARTED: 8/24112 DATE COMPLETED:

8/26/12 BORING LOG KB-1 fjI .I7~ A\ Lo SAMPLE z LU w* aL a. C%U) SOI DECRPTO z. uj 0D REMARKS*~ ac 0 Z ~._j W <' ,( a 0 U)LU ) U) u0 I 102-90 SM sa-032 SPI SM 107 -g5 Ba-033 100 112 Ba-4,034 BS-035 SWI SP SM SM POORLY GRADED SAND WITH SILT, dark olive brown (2.5YR 3/3), massive, dense, wet, fine sand, massive POORLY GRADED SAND WITH SILT, dark olive brown (2,5YR 3/3), massive, dense, wet, fine sand, massive Sand coarsens to fine to medium, massive, dark yellowish brown, grades siltler at 98'WELL GRADED SAND WITH SILT AND GRAVEL, dark grayish brown (2.5Y 4/2), dense, wet, -10% fines, fine to coarse sand, well-rounded, 10-15% fine gravels SILTY SAND, dark olive brown (2.5Y 3/3), dense, wet, 20-30% fines, fine sand Fine gravels (5%) between 105' & 106', 15-20% fines SILTY SAND, dark olive brown (2.5Y 3/3), dense, wet, 15-20% fines, massive fine sand, massive Grades slitier 117 t 105 ssa-0361-110 an.037 122 BORING LOG Page'Number 6 of-

.. .Consulting Engineers

& Geologists, Inc......4/ 812 West Wabash,. Eureka, CA- ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: /186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/24/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

8/26/12 LOGGED BY: JPB BORING LOG KB-1 Ga-038 ,039 Ba-'040 127 132 137 142 115 120-125-130 Ba-41-4 042 POORLY GRADED SAND WITH SILT, dark olive brown (2.5Y 3/3), massive, dense, wet, medium, well-rounded sand, 10% fines Trace fine gravels and medium to coarse sand from 116'-116.5'CLAY, light bluish gray, stiff, moist, stiff, intermittent beds<1" thick------------------

---

.-.

-- ....----....-......-

" CLAY, light bluish gray, stiff, moist, stiff, intermittent beds ,<1" thick CLAY, light bluish gray, stiff, moist, stiff, intermittent beds<1" thick Trace fine gravels Becomes very dark bluish gray (GLEY 2 3/1), at 122', medium to coarse sand SP/SM, crudely bedded SILTY SAND, dark bluish gray (GLEY 108 311), dense, 30% fines, 5-10% fine gravel, fine to medium sand, well-rounded, massive Decreases in fines 10-20% at 127'POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 10B/311), wet, medium dense to dense, fine to medium sand, -10% fines, massive Ba-D43 BORING LOG Page Number 6 of 9 Consulting' Engineers

& Geologists, Inc.I812 West Wabash; Eureka, CA ph. (707)441-8855 W.(707)441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB I SAMPLE -LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: 1186 Feet BGS DATE STARTED: 8/24/12 DATE COMPLETED:

8/26/12 BORING LOG KB-1 147 }-135-140 152 157 Ba-,045 140 No recovery POORLY GRADED SAND WITH SILT, dark bluish gray (GLEY 2 10B 3/1), wet, dense, fine to medium sand, subrounded, gradational stratification, fine to coarse sand,-5% fine gravels In lower 6" (very dense)1451'SPI SM Ba0 046 162 t 150 167 t 155 BORING LOG Page Number 7 of 9 Consulting Engineers

& Geologists, Inc.812lWest;Wabash, ,Eureka, CAl ph. (707) 441855 fax. (707)44 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Powe PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: DATE STARTED: 8/24/12 DATE COMPLETED:

8/26112 41-8877 BORING LOG-r Plant KB-I_186 Feet BGS-SAMPLE z Lu-L U.1 W L DW U REA I"SOIL DESCRIPTION Z R REMARKS U- L-j Lu ~ U) U) C U U) i _ _ _ _ _ __ _ _ _ __ _ _ _,,, z J .-0. 0 0 ca CL POORLY GRADED SAND WITH SILT CLAY, greenish black (GLEY 2.5/1 10Y), very stiff, moist, rare medium gravels No recovery (easy drilling), loose sand? silt?see driller note CLAY, dark gray, stiff to hard, wet, low plasticity, <5% fine sand>4.5 CL BORING LOG Page Number8 of 9

.'I 'Consulting Engineer 812 WestWabash, Eureka, PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB rs & Geologists, Inc..-4 ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG LOCATION:

Humboldt Bay Power Plant KB-1 ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: 186 Feet BGS.DATE STARTED: 8/24/12 DATE COMPLETED:

8/26/12 ~~ I SAMPLE 0 -0 Iz ' SOIL DESCRIPTION M KS W l R M 1 wow LA _ _ _ __ _ _ _____ _ _192, SILT/CLAY, very dark gray, very stiff, moist, low plasticity, occasional shell fragments, gradational variations in silt/clay content, <5% fine sand 197+202 T 207 BORING LOG Page Numberr 9 of 9 Consulting Engineers

& Geologists, Inc.812,West Wabash, Eureka, CA ph. (707)441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING:.__

1I DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

9/15/12 LOGGED BY: JPB .86 Feet BGS BORING LOG KB-2 T 12 to-r r-~.---¶-,-r

-1 7-t5 3 3 5 22 f1 0 8b-001 Bb-002 8Sb-003 Bb-,004 Bb-005 sb-006 Bb-007 SSb-008 27-15 2 2 2 6 GRAVEL AND SAND (imported fill for working surface)CLAY, dark yellowish brown to gray (mottled), stiff, moist,-5-10% sand, low plasticity

,.CLAYEY SAND, light brown, medium dense, moist?, fine sand, -30% fines SILT WITH SAND, dark yellowish brown to brownish gray (mottled), firm, moist?, 25% fine sand, low plasticity Becomes dark bluish gray Becomes clayeyer, less sand with organic fines Laminated beds 2-3 mm with variable sand content 5-25%LEAN CLAY, very dark greenish gray, moist?, soft to firm,-5% fine sand LEAN CLAY WITH SAND, dark greenish gray, moist, stiff to very stiff, fine laminated (1-2 mm)LEAN CLAY, dark greenish gray, moist, firm, <5% fine sand Becomes mottled strong brown to brownish gray, 5-10%1.0 1.25 1.0 2.0 0.5 1.5 2.5 1.75 0.751 10 32 t20 BORING LOG Page Number 1 of9 Consulting Engineers

& Geologists, Inc.S812 West Wabash, Eureka, CA-ph.(707)41-8855 fax.,(707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: /186 Feet BGS DATE STARTED: 9/12112 DATE COMPLETED:

9/15/12 SAMPLE I Z 0: co c- W zO w " SOIL DESCRIPTION REMARKS uj 0 Wu 0 US~-, W I W 0 ! W- I-0_ 0 CA c.37.25 42 47 52 sand, homogenous SANDY CLAY, strong brown to brownish gray, stiff to very stiff, wet, low plasticity, 20-30% fine sand, homogenous SILTY SAND/SANDY SILT, dark brown to strong brown to browish gray, medium dense to stiff, wet, interbedded layers (0.5"-3')SP/SM POORLY GRADED SAND WITH SILT, dark yellowish brown (IOYR 3/6), dense, wet, fine sand, 15% fines*WELL GRADED SAND WITH SILT AND GRAVEL SITY SAND, dark yelloiwsh brown, medium dense, wet, fine sand, stratified with coarser zones, -20% fines WELL GRADED SAND WITH SILT AND GRAVEL SITY SAND, dark yellowish brown, medium dense, wet, fine sand, stratified with coarser zones, -20% fines POORLY GRADED SAND WITH SILT, brown (10YR 4/3), dense, wet, fine sand, 15% fines WELL GRADED SAND WITH GRAVEL AND POORLY GRADED GRAVEL WITH SAND, color?, dense, wet, subangular to subrounded send and gravel, gravels up to 35 40 I 3.5 L BORING LOG Page Numbr 2 of 9 , .L .. ......

--Consulting Engineers

& Geologists, Inc.42 D 8.12 West Wabash, Eureka, CA. ph. (707)441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: 186 Feet BGS DATE STARTED: 9/12/12 DATE COMPLETED:

9115/12 BORING LOG KB-2 SAMPLEz Z Z m.j a WSOIL DESCRIPTION W o REMARKS M~ to0: .57.62 67 72 77 r 4 5 t 50 55'60-65 Bb-016 s8b-017 Bb-018 Bb-019 SSb-020 2" in distinct zones, poor recovery makes difficult to determine full thickness and extent of deposits Stratified with SM & SP CLAY? (based on drilling resistance and mud performance), no recovery of clay, so may have bene tight clear sand?SITY SAND, dark yellowish brown, dense, wet, 30 %fines, fine sand, stratified with SP in 1-6" beds, gradational Grades.into SP POORLY GRADED SAND WITH SILT, dark yellowish brown, dense, wet, stratified with SM CLAY? (based on drilling resistance and mud performance), did not recover in core LEAN CLAY, very dark bluish gray (GLEY 2 108 4/1), stiff, moist, -5% fine sand Grades to dark bliush brown (iron stained)SILTY SAND, strong brown, dense, wet, stratified with tink (<1") layers of clay LEAN CLAY, dark bluish gray (GLEY 2 lOB 4/1), stiff, moist, laminated with silty sand and sandy clay, -5% fine sand Interbeds of silt BORING LOG Page Number 3 of 9 S..Consulting Engineers

& Geologists, Inc.812 West Wabash, Eureka,.CA

-ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: 186 Feet BGS DATE STARTED: 9/12/12 DATE COMPLETED:

9/15/12 BORING LOG KB-2-SAMPLE zW SOIL DESCRIPTION REMARKS a U. M R.1W 0( U) (O) 0 a 82 t-70 Becomes dark brown (10YR 3/3)87 92 75'80 Stratified sand and clay, iron stained at clay/sand contacts Laminated from 76.5' to 77.5' (-1/4 inch In 1/2 inch beds)...._.,- --- ---------.

... ..--- ;,-- -- -..,- ...- '- .POORLY GRADED SAND WITH SILT, dark yellowish brown, dense, wet, 10-15% fines, fine to medium sand, interbedded with thin (1/4 inch) beds of clay POORLY GRADED GRAVEL WITH SILT AND SAND, dark brown, dense, wet, subrounded to well rounded sand and gravel, 10-15% fines, 30-40% sand, gravely up to 1.5".. ....--- --- -.--. --L-. ..POORLY GRADED SAND WITH SILT, dark yellowish brown, dense, wet, 10-15% fines, fine sand, occasional beds of coarse sand and minor fine gravel Grades into SILTY SAND, 15-20% fines or occasional coarse sand bed with fine gravel, typically 4-6" thick 97 85 BORING LOG Page Number 4 of 9 Consulting Engineers

& Geologists, Inc.~3'§2 "7 812'West:Wabash, Eureka, CA ph. (707) 441-8855 fax.x(707)441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: 1186 Feet BGS DATE STARTED: 9/12/12 DATE COMPLETED:

9/15/12 SAMPLE-z C) I- 'SOIL DESCRIPf1ON z REMARKS z z a 0 U W 0 U) 0)UU~~ _ _ _102 '0 14 37 50/5" 1074.95 112 f 100 8b-026'Bb-027 Bb-028 SM SWi Sand grades to coarser Poorly graded sand with silt in shoe POORLY GRADED SAND WITH SILT, dark brown (lOYR 3/3), dense, wet, 10-15% fines, fine to medium sand with occasional coarse sand/fine gravel Grades to very dark grayish brown (2.5Y 3/2)SILTY SAND, dark brown, dense, wet, fine to coarse sand, 5-10% fines subrounded to rounded gravel, 20-30% fines, (SHOE), (relative position, contacts, and extent unknown)WELL GRADED SAND WITH SILT AND GRAVEL, very dark grayish brown, very dense, wet, 10-15% fines, gravel 117 122-105 110 SPI/M Bb-029 POORLY GRADED SAND WITH SILT, very dark grayish brown, very dense, wet, 10-15% fines, fine sand, occasional gravel 1-3", stratified with variable coarse sand beds (2-4' thick)30 BORING LOG Page NumberS5 of 9

( .Consulting Engineers

& Geologists, Inc.t....... 812 WestWabash, Eureka, CA -ph. (707) 441-8855 fax. (707) 441-88 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Pil PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: DATE STARTED: 9/12/12 DATE COMPLETED:

9/15/12 177 BORING LOG ant KB-2/186 Feet BGS-SAMPLE>~ ~ 01 U 40U SOIL DESCRIPTION z UREMARKS IL I wu 0_u 0 W:' 0 3I I .C SP4M Bb-030 127=115.132 -t 120 SPI$M Bb-031 POORLY GRADED SAND WITH SILT, very dark grayish brown, very dense, wet, 10-15% fines, fine sand, occasional gravel 1-3", stratified with variable coarse sand beds (2-6" thick), interbeds of silty sand rare (-1")POORLY GRADED SAND WTH SILT, very dark greenish gray (GLEY 1 56Y 3/1), very dense, wet, fine to medium sand, homogenous, 15% fines POORLY GRADED SAND WITH SILT, very dark greenish gray (GLEY I 56Y 3/1), very dense, wet, fine to medium sand, homogenous, 15% fines, interbeds of coarser sand occasional

---

------- ----POORLY GRADED SAND WITH SILT, very dark greenish gray (GLEY I 56Y 3/1), very dense, wet, fine to medium sand, homogenous, 15% fines, Interbeds of coarser sand occasional Becomes dense 5.61, 12A4 125 137 sP/142 t 130 sPi4M a, 0b-,, ,032 BORING LOG Page Number6 of 9

-Consulting Engineer S812 West Wabash, Eureka, .C PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB rs & Geologists, Inc. 7-A ph.(707) 441-8855 fax. (707")441-8877 BORING LOG LOCATION:

Humboldt Bay Power Plant KB-2 ELEVATION:

12 feet DIAMETER/DEPTH OF BORING:_/

186 Feet BGS DATE STARTED: 9/12/12 DATE COMPLETED:

9/15/12 I SAMPLE ji-Jz LU t 0~~ C ( >=. -0u SOIL DESCRIPTION N REMARKS L < z g. oL _z -ul uj 0 j 0--j L3 Cu W a.0 L3 LU <() WUL 0 147 152 157 135-140-145 POORLY GRADED SAND WITH SILT, very dark greenish gray (GLEY 1 56Y 3/1), very dense, wet, fine to medium sand, homogenous, 15% fines, interbeds of coarser sand occasional Becomes dense POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 lOB 3/1), very dense, wet, fine to medium subangular to subrounded sand, 15% fines, occasional beds of coarse sand (2-6" thick)POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 10B 3/1), very dense, wet, fine to medium subangular to subrounded sand, 15% fines, occasional beds of coarse sand (2-6" thick), homogenous Bb-033 10.6 162 -150 03SSb- 0/1 034 I 6,-155 167 XA035 BORING LOG Page Number 7 of 9 Consulting Engineers

& Geologists, Inc."jJ27 812West;Wabash,, Eureka, CA ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: /1l DATE STARTED: 9/12/12 DATE COMPLETED:

9/15112 BORING LOG KB-2 86 Feet BGS/pf7-SAMPLE-SOIL DESCRIPTIONREAK

.1 Z a.a CL Wz uj 0 172 177-160 K165 ab-038 Bb-* 037Bb-039 POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 10B 3/1), very dense, wet, fine to medium subangular to subrounded sand, 15% fines, occasional beds of coarse sand (2-6" thick), homogenous POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 10B 311), medium dense to dense, wet, fine to medium sand, subrounded, 15% fines, rare coarse sand, homogenous POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 10B 3/1), medium dense to dense, wet, fine to medium sand, subrounded, 15% fines, rare coarse sand, homogenous, crudely bedded with variations in coarse sand CLAY, very dark gray (GLEY I N 3/), very stiff, moist, homogenous, low plasticity, occasional to common shall fragments (zones)Homogenous clay 182. 170 3.5 3.0 4.0 4.5 3.75 4.5>4.5.4.0 3.5 4.0>4.5>4.5>4.5>4.5 11.'s 187-175 1 ... BORING LOG Page Number 8 of 9 Consulting Engineers

& Geologists, Inc.812 West Wabash, Eureka, CA ph. (707) 441-8855 fax. (707) 4414877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING:_ 1 DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

9/15/12 LOGGED BY: JPB 36 Feet BGS BORING LOG KB-2 DO W Ai SAMPLE Z 4 -4 I~ 1o 9 Z) 0 > SOIL DESCRIPTION W o REMARKS w co 1 W4 0 Cn W 0 0 0 Z) _ _ _ __ _ _ _ _192 197 202 207 Thick accumulations of shelly debris Slight variations In slit content within crudely bedded zones Thick accumulations of shelly debris BORING LOG Page Number 9 of 9 Consulting Engineers

& Geologists, Inc.: f 812.West Wabash, Eureka, CA ph. (707) 441.8855 fax. (707) 441.8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING:(",,'/

201 Feet BGS DATE STARTED: 9/4/12 DATE COMPLETED:

glhl BORING LOG K13-3 SAMPLE LU X C, REMARKS -.0MSOIL DESCRIPTION REMARKS.~ z~~wu oF W Z a. oUL LU 01~-n..j 0 LU 0 ) o U) ..a 12 17 F 0: CONCRETE I AGGREGATE BASE ROCK (up to 3")SILTY SANDIPOORLY GRADED SAND (FILL), mixture of silt and sand/22t 1 0 I 27 32-15-20 SSc-001 go-002 SSM-003 Bo-004 2 3 4 LEAN CLAY, strong brown, stiff to very stiff, moist, low plasticity, <10% fine sand Grades to bluish gray at 11.5'LEAN CLAY, strong brown, stiff to very stiff, moist, low plasticity, <1 0% fine sand LEAN CLAY WITH SAND, very dadr greenish gray (GLEY 2 586 3/1), medium stiff to stiff, moist, low plasticity, 20% fine sand, occasional plant fiber/roots 2 3 5 1.5 2.5 2.5 1.25 1.0 1.0 1.0 3.5 1.0 BORING LOG Page Number I of 10 Consulting Engineer 812 West Wabash, -Eureka, Cl PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB s & Geologists, Inc.A ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG LOCATION:

Humboldt Bay Power Plant KB-3 ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: /201 Feet BGS DATE STARTED: 914112 DATE COMPLETED:

___SAMPLE i 0 W. 0.1 SOIL DESCRIPTION z REMARKS U .J Z!~ g w11 L4 Uj 09_0 NOa-.005 BC-006 SSc-007 8 12 12>4,5>4.5>4.5"25 37 10 13 10 SILTY SAND, dark yellowish brown to light gray (mottled), medium dense, wet, 15-40% fines, fine sand Grades sandier with depth with 1" intervals of clayey sand/sandy clay POORLY GRADED SAND WITH SILT, dark yellowish brown, medium dense, wet, 15% fines, fine sand, thin laminated lenses of silty sand/sandy silt Thin (<0.25") laminations of silty sand/sandy silt from 28.5'-29.5'Sand coarsens to fine to medium sand, massive 42 t30 47 SSc-009 Bc-010 Sic-011 sBc-013 17 15 18 10 11 12 Interbedded silty sand/sandy silt with 15% fine gravel SILTY SAND, dark yellowish brown, medium dense, wet, fine to medium sand, 30% fines, grading sandier with depth'SILTY GRAVEL SAND, up to 2' gravel, well rounded 'CLAY, 2" layer, bluish gray SILTY SAND WITH GRAVEL, dark brown (10YR 3/3), dense, wet, fine to coarse sand, subrounded to well rounded, 15-20% fine to medium gravel, 15-20% fines POORLY GRADED SAND, dark grayish brown (10YR 4/2), 52 t-40 14 27.1 BORING LOG Page Number 2of 10 Consulting Engineers

& Geologists, Inc...1. 812 West-Wabash, Eureka-CA ph, (707) 441-8856 fax. (707) 41.8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: 121 DATE STARTED: 9/4/12 DATE COMPLETED:

BORING LOG 1<KB-3 01 Feet BGS ...--SAMPLE 0 Z U ~LU~ ~SOIL DESCRIPTION 0~W aI Z Za_J uj 0, .L 0 9- Io 0~~ 0 (0 gt W 1 1 1 IJ-45 57 80-014 8Sc--015 s0-.016 62 -t 50 SSo-017 SSc-016 dense, wet, 5-10% fines, fine sand Coarse sand layer (2')Grades to SILTY SAND, dark grayish brown (IOYR 4/2), dense, wet, 20-30% fines, massive 6" layer with 10-20% gravel, well rounded, up to 1.5" SILTY SAND, dark grayish brown (10YR 4/2), dense, wet, 20-30% fines, massive Assume shoe plugged on gravel lense at 50'CLAYEY SAND, light gray, dense, 40% fines (2" in SPT)WELL GRADED GRAVEL WITH SAND POORLY GRADED SAND WITH SILT, dark yellowish brown (1 OYR 4/4), dense, fine sand, -10% fines WELL GRADED GRAVEL WITH SAND, .color??, dense, wet, medium to coarse gravel (up to 3"), well rounded SILTY SAND, dark yellowish brown, medium dense to dense, wet, fine to medium sand, 20% fines'ClY,V ,dark ibluish (GLEY 2.5PB'A/1

), veij stlff,.'moist, lowpqistIblty, -5%~fi~ne sand POORLY GRADED SAND.WITHSILT, dirk yellowish brown (110YR 3/4)', medium dense, .wet," e to.medium sand,i-10-15%

fines Zones of iron staining Thin lenses of silt/clay

(<1/2")19.C 0c-.019 67-55 3.5 3.5 4.5 72 t60 Be-021 SSc-022 10.0 BORING LOG Page Number 3 of 10 T 'Consulting Engineers

& Geologists, Inc.812Wqst;Wabash,:Eureka, CA ph.(707)441-8855 fax.(707)441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: /201 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/4/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

LOGGED BY: JPB BORING LOG K13-3 SAMPLE ze -C Z a2 SOIL DESCRIPTION REAK Z LU Z.0- 0 W c' IL.77 CL-p65 I'70 82 87 iSM Brownish gray below 63'LEAN CLAY, dark yellowish brown grading to dark bluish gray, very stiff, moist to wet, interbedded with layers of sand, fine (1-2 mm) laminations common Thin laminations of clean sand Very thin <1 mm laminations of silt/clay with sandy intervals, typically 0.25-0.5" in thickness and iron-stained SILTY SAND, dark yellowish brown, dense, wet, fine to medium sand, 15-30% fines, interbeds of clay typically 118-114" thick SILTY SAND, dark yellowish brown, dense, wet, fine to medium sand, 15-30% fines, interbeds of clay typically 1/8-1/4" thick Lay-ers of clay (<1 ") typically with zones up to 6" thick SILTY SAND, dark yellowish brown, very dense, wet, fine to medium sand, 5-10% fine gravel, well rounded to subrounded, fine to coarse sand POORLY GRADED SAND, dark yellowish brown (10Y 3/4), dense, wet, fine sand, -5% fines>4.5 2.5 1.5 3.5>4.5 2,5>4.5 z75 i SM SM SP 92 "80 BORING LOG Page Number 4 of 10

(-..Y7 Consulting Engineers

& Geologists, !nc........ 812 West Wabash,, Eureka CA ph. (707) "1-8855 hfax (707) 4 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Pow PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB ELEVATION:

12 feet DIAMETER/DEPTH OF BORING DATE STARTED: 9/4/12 DATE COMPLETED:

41-8877 BORING LOG er Plant KB-3/201 Feet BGS .. .n) i SAMPLE---zw z 0 90> _j a _ _ _ _ _ _ _ _ _ _ _ _ X5 _ _ _ _97 t5 sc- : 030 SSc-031 0c-032 102 4.5 X: .033 WELL GRADED SAND WITH GRAVEL, very dark grayish brown (10YR 3/2), very dense, wet, subrounded to well rounded sand and fine gravel, -30% fine gravel up to 1/2",-5% fines Gravel content decreases with depth, fines increase POORLY GRADED SAND WITH SILT AND GRAVEL, dark olive gray (5Y 3/2), dense, wet, fine to medium sand, subrounded to well rounded sand and fine gravel, 20%fine gravel, up to 1/4" POORLY GRADED SAND WITH SILT AND GRAVEL, dark olive gray (5Y 3/2) grades to very dark greenish gray (GLEY 1 106Y 3/1), dense, wet, fine to medium sand, subrounded to well rounded sand and fine gravel, 20%fine gravel, up to 1/4" WELL GRADED SAND WITH SILT AND GRAVEL, very dark greenish gray, dense, wet, fine to coarse sand, subrounded to well rounded sand and fine gravel (up to 3/8"), -10% fines, 30% fine gravel Poor recovery, so relative position of described sample Is unknown SILT/CLAY, very dark grayish green (GLEY 1 56 3/2), stiff, wet, -0l% fine sand, thin laminations unkonreco-very, so relative position of described sample i-*unknown-.95 107 Bc-034 112 -,10 105,1 BORING LOG Page Number 5 of 10 Consulting Engineer 5... 812 West Wabash. Eureka', C.PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB rs & Geologists, Inc.A ph. (707) 441-8855 1Fax. (707) 441-8877 BORING LOG LOCATION:

Humboldt Bay Power Plant KB-3 ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: /201 Feet BGS DATE STARTED: 9/4/12 DATE COMPLETED:

___-SAMPLE 0 0>, .SOIL DESCRIPTION z 'L4 a REMARKS J .J > ),k, 0 0 CL CL-. 0 mf 0 .LU~~ ~ C.i.~0.j W I, IS IOU 23 I LUJ 0 U) Cn .U)0~ 1j X.- :3___117 T 105 122 127-110-115 036* Bc-037 Bc-038 Bc-,039 BC-040 Bc-0417 SILTICLAY.

very dark grayish green (GLEY 1 56 3/2), stiff, wat .1 0%Tfnesand'.thin laminations

........WELL GRADED SAND WITH SILT AND GRAVEL, very dark greenish gray, dense, wet, fine to coarse sand, subrounded to well rounded sand and fine gravel (up to 3/8"), -10% fines, 15-20% fine gravel, massive WELL GRADED SAND WITH SILT AND GRAVEL, very dark greenish gray, dense, wet, fine to coarse sand, subrounded to well rounded sand and fine gravel (up to 3/8"), -10% fines, 15-20% fine gravel, massive Grades siltier tSILTY SAND WITH GRAVEL, very dark greenish gray, dense, wet, subrounded to well rounded, 20-30% fines, 15-20% gravel WELL GRADED SAND WITH SILT AND GRAVEL, very dark greenish gray, dense, wet, fine to coarse sand, subrounded to well rounded sand and fine gravel (up to'3/8"), -10% fines, 30% fine gravel POORLY GRADED SAND, very dark greenish gray, very dense, wet, <5% fines, fine sand Zones of gravel and coarse sand (location and abundance uncertain due to poor recovery)SILTY SAND, very dark greenish gray, dense, wet, 20-30%.1 fines, fine to medium sand (SHOE),POORLY GRADED SAND, very dark greenish gray, very 1dense, wet, <5% fines, fine sand WELL GRADED SAND WITH GRAVEL, very dark greenish gray, dense, wet, fine to coarse well-rounded sand and fine gravel (up to 3/8"), <5% fines-----------

---

WELL GRADED SAND NMTH GRAVEL, very dark greenish gray, dense, wet, fine to coarse well-rounded sand and fine gravel (up to 3/8'%, <5% fines WELL GRADED SAND WITH GRAVEL, very dark greenish gray, dense, wet, fine to coarse well-rounded sand and fine gravel (up to 3/8"), <5% fines 132 1 120 137 T 125 BORING LOG Page Number 6 of 10 Consulting Engineer 4,7 812 West Wabash, Eureka,',Pj PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB as & Geologists, Inc.A ph. (707) 441-8858 -faxt. (707) 441-8877 BORING LOG LOCATION:

Humboldt Bay Power Plant KB-3 ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: I 201 Feet BGS DATE STARTED: 9/4/12 p DATE COMPLETED:

51;1 ho!/\A'ý-- SAMPLE z z UU le -q~ c- SOIL DESCRIPTION Z0 REMARKS U. U: (9 CL P z IL WLU W 0 ( LU ~Z I i~~ > E.W LU <4. 0 I-LU g, 0U U) (f), 51 _ __ _Bc-042 142 147 152 157 130-135-140 Bc-043 POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 108 3/1), dense, wet, fine to medium sand with zones of coarse sand, grading Into fine sand at lower end of core, 10-15% fines POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 108 3/1), dense, wet, fine to medium sand with zones of coarse sand, grading into fine sand at lower end of core, 10-15% fines Sand coarsens between 132.5'-135', 5-10% fine gravel POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 108 3/1), dense, wet, fine sand, <5% fine gravel POORLY GRADED SAND WITH SILT, very dark bluish.gray (GLEY 2 108 3/1), dense, wet, fine sand, <5% fine gravel, massive POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 108 3/1), dense, wet, fine sand, <5% fine i ,!Bc-044-145 BORING LOG Page Number 7ef 10 Consulting Engineers

& Geologists, Inc..2I 812 West Wabash, Eureka, CA ph. (707)441-855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: 2C DRILLING METHOD: Mud Rotary DATE STARTED: 9/4112 SAMPLER: Punch Core & SPT DATE COMPLETED:

LOGGED BY: JPB 31 Feet BGS BORING LOG KB-3 LW] !.! ZrI ,'gravel, massive, occasional coarse sand POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 58 3/1), dense, wet, fine to medium sand, subangular to subrounded, 10-15% fines, occasional zones of coarse sand and fine gravel (-5%)POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 58 3/1), dense, wet, fine to medium sand, subangular to subrounded, 5% fines, occasional zones of coarse sand and fine gravel (-5%)WELL GRADED SAND WITH GRAVEL, very dark bluish gray, dense, wet, fine to coarse sub-rounded sand, -5%fines, 20% fine gravel to 1/2" POORLY GRADED SAND, very dark bluish gray, medium dense, wet, fine to medium sand, <5% fine gravel, 10%fines BORING LOG Page Number 8 of 10 I Consulting Engineers

& Geologists, Inc......... 812 West Wabash, Eureka, CA ph.(707)441-8855 fax. (707)441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING:___/

2C DRILLING METHOD: Mud Rotary DATE STARTED: 9/4/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

LOGGED BY: JPB)1 Feet BGS BORING LOG KB-3 LM ~iL SAMPLE z z 0SOIL DESCRIPTION UZ REMARKS= Z = ,- _ CD a- ,=.0 U W LU 0 r... .I-IJ J J -;n _ _ _ _ _ _ _ _ _ W :1 182 170 187 -.1751 POORLY GRADED SAND WITH GRAVEL, very dark bluish gray, dense, wet, fine to medium sand, -20% fine gravel, 10% fines, possible more based on drilling resistance (limited recovery of this material)Wood chunk, 5" long, 3" across, embedded in sand CLAYEY SAND, stong brown to light grayish brown (mottled), loose to medium dense, wet, fine to medium sand, 50% fines, sharp contact with SP above Contact based on drilling performance CLAY, small piece recovered after cleaning out hole CLAY, dark gray (GLEY 1 N 4/), very stiff to hard, wet, medium plasticity, <5% fine sand (sample disturbed heavily) (some material recovered in short core)CLAY, dark gray (GLEY 1 N 4/), very stiff to hard, wet, medium plasticity, <5% fine sand, laminated with common shelly debris, thin intervals of silty laminations 192 t o180 197 t 1851 BORING LOG Page Number 9 of 10 Consulting Engineers

& Geologists, Inc. .812 West Wabash, Eurpka, CA ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: /2 DRILLING METHOD: Mud Rotary DATE STARTED: 9/4/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

LOGGED BY: JPB BORING LOG KB-3 01 Feet BGS SAMPLE I--I i ° 00i, z --L A.* " -SOIL DESCRIPTION , REMARKS'.JJ 0 0_202 207 g 212 BORING LOG Page Number 10 of 10 Consulting Engineers

& Geologists, Inc.812 West Wabash, Eureka, CA ph. (707) 441-8855 fax.(707)-441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: -&-el 186 Feet BGS DATE STARTED: 8/20/12 DATE COMPLETED:

8/30/12 BORING LOG KB-4 12 T 0 1 10" of Imported gravel fill, angular, "washed", dry, filter Nfabric, non-woven at 10"/.5.17 SSd-001 2 5 7 4 .d-S002 22 ti1 SSd-003 3 5 8 SILT WITH GRAVEL, dark bluish gray, stiff, moist, fine to b medium gravel (fill)SILT, light olive brown (2.5Y 5/3), medium stiff, moist, <5%sand, low plasticity Grades to clayey with depth LEAN CLAY, olive brown (2.5Y 5/3), medium stiff, moist, low plasticity Varies from moderately stiff to stiff, becomes dark gray (2.5Y 4/1) at 7'Grades silty at 8.5'SILT, dark greenish gray (106Y 4/1), stiff, moist, low plasticity Thin interbeds of SILT WITH SAND (11 cm)SILTY SAND, dark greenish gray (106Y 4/1). medium dense, moist to wet, 40-50% fines, fine sand INTERBEDDED SILT AND SILTY SAND, very dark greenish gray (106Y 3/1), medium dense???, moist to wet, fine sand, rare wood fragments, Interbeds 1-2 cm INTERBEDDED SILT AND SILTY SAND, very dark greenish gray (106Y 3/1), medium dense???, moist to wet, fine sand, rare wood fragments, interbeds thicken to 3-4 cm 1.0 1.25 1.0 2.0 0.5 1.5 2.5 1.75 0.75 27-32-15-20 Bd-005 SSd-88d-006 7 8 11 8 13 18 BORING LOG Page Number I of 9

( YConsulting Engineers

& Geologists, Inc."812 W st Wabash, Eure'ka,'CA ph. (707) 441-8855 fia. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: __ 1186 Feet BGS DATE STARTED: 8/20/12 DATE COMPLETED:

8/30/12 BORING LOG KB-4.n1i3 ~SAMPLE S. z z ' ~ , SOIL DESCRIPTION z 3 REMARKS z Z0 3: z Z-~ ~ W0~'-~C. [- M'3 0 0 0 4-l 2< a 1.- -a 0 X a. CL U) 1.. CL..j IL4.0 3 W, 0 CI) U) 0 W 0 Z.37 42 47"25-30 SILTY SAND, dark gray, medium dense to dense, wet, fine sand, -30% fines SILTY SAND, strong brown (7.5YR 4/6), dense, wet, fine sand, -30% fines Grades to dark yellowish brown at 27'Sand coarsens at 28'WELL GRADED SAND WITH SILT, dark yellowish brown (10YR 4/4), dense, wet, well-rounded gravel, 80% fine to coarse sand,__ sand/gravel POORLY GRADED SAND WITH SILT, dark yellowish brown (IOYR 4/4), very dense, wet, -15% fines, fine sand POORLY GRADED SAND WITH SILT, dark yellowish brown (1OYR 4/4), very dense, wet, -15% fines, fine sand Thin lense (0.25") of well graded sand with slit and gravel'SILTY GRAVEL WITH SAND, dark yellowish brown, dense, wet, -15% fines, 40% fine to coarse sand, well rounded medium to coarse gravel (up to 2')

GRADED SAND WITH SILT, dark yellowish brown, dense, wet, fine to medium sand, -20%fines Iron stained, gravelly sand POORLY GRADED SAND WITH SILT, very dark brownish gray (2.5YR 3/2), dense, wet, fine sand Grades to dark yellowish brown at 43'7.3"35 52:t40 I CLAY, dark gray, stiff to very stiff, moist to wet, thin clay at. \1 3.5 BORING LOG Page Number 2 of 9 Consulting Engineers

& Geologists, Inc.... 812 West Wabash, Eureka, CA -ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: /186 Feet BGS DATE STARTED: 8/20112 DATE COMPLETED:

8/30/12/I BORING LOG KB-4 SAMPLE -1E -~ SOIL DESCRIPTION 06 REMARKS IL. ~ 0)w I_j Z Z. 'li n CD Co ýI) Un_ I _ _"45 57 bottom of core run capped with gravelly sand (iron stained)POORLY GRADED SAND WITH SILT, dark yellowish brown (lOYR 8/6), very dense, wet, fine sand, -15% fines POORLY GRADED SAND WITH SILT, dark yellowish brown (10YR 8/6), very dense, wet, fine sand, -15% fines Sand coarsens at 50'SILTY SAND, dark yellowish brown (10YR 316), dense, wet, fine to coarse sand, 20% fines, 10% fine gravel, well-rounded, gravels with Isolated zones 62 t 50 4.0 67 72-60-65 Gravel content increases to 15% below 55'POORLY GRADED SAND WITH SILT, dark brown (10YR 3/3), dense, wet, fine to medium sand, massive WELL GRADED SAND WITH SILT AND GRAVEL, dark yellowish brown, dense, wet, fine to coarse well-rounded sand and gravel, -10% fines, 10-15% gravel-.- --- --_ -------- ---POORLY GRADED SAND WITH SILT, dark yellowish brown (10YR 3/4), dense, wet, fine to medium sand, 10-15% fines-P-O-O-RL-Y-GRADED SAND WITH SILT, derk yellowish 77 BORING LOG Page Number 3 of 9 Consulting Engineers

& Geologists, Inc.#S271257 812 West.Waba;sh,.Eureka,.CA, ph.907).441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: /186 Feet BGS DATE STARTED: 8/20112 DATE COMPLETED:

8/30/12 BORING LOG KB-4-SAMPLE.0 0 0 oSOIL DESCRIPTION luRMAK'-j z 3 0 w A. M -ui W , 0 u W- 0(1 ~ i .~ _ _ _ _82 t70 SSd-022 Bd-023 SSd-024 87'.7 5 brown, dense, wet, fine sand, <5% fines SILTY SAND/POORLY GRADED SAND, dark yellowish brown, dense, wet, fine to medium sand, 10-20% fines, massive, Iron stained bands POORLY GRADED SAND WITH SILT, dark yellowish brown, dense, wet, fine to coarse sand, 5-10% fine gravel, subrounded to well rounded, 5-15% fines (variable), crudely bedded POORLY GRADED SAND WITH SILT, dark yellowish brown, dense, wet, fine to coarse sand, 5-10% fine gravel, subrounded to well rounded, 5-15% fines (variable), crudely bedded POORLY GRADED SAND, dark brown (10YR 3/3), dense, wet, -5%fines, fine to medium sand SILTY SAND, olive brown (2.5Y 4/3), dense, wet, 20-30%fines, fine to medium sand, rare fine gravel Bd-, 025 92 t 80 97 .85: Bd-027 BORING LOG Page-Number4ofg

( U 7Consulting Engineers

& Geologists, Inc. _ _t11j( 82'West:Wabash, Eureka:, CA,, ph. (707) 441-8855 -fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETERIDEPTH OF BORING: 1186 Feet BGS DATE STARTED: 8/20/12 DATE COMPLETED:

8/30/12 BORING LOG KB-4-SAMPL E_ a. 9 -Z4 SOIL DESCRIPTION i REMARKS Z: _j 21 0 0 .~u 4 61___ W < LJ 0- U) -__102 107 112 POORLY GRADED SAND, dark brown, dense, wet, fine to medium sand, rare layers of fine to coarse sand, rare fine gravel WELL GRADED SAND, dark brown, dense, wet, fine to coarse, sub-rounded to well-rounded sand, intermittent clay lenses, 15% fine gravel, 10% fines Thin clay layers, greenish gray POORLY GRADED SAND, dark brown to olive gray (5Y 4/2), dense, wet, fine sand, -5% fines WELL GRADED SAND WITH SILT, dark grayish brown, dense, wet, fine to coarse sand, sub-rounded to rounded,-5-15% fines, 10% fine gravel, Interbedded with fine sand beds (2-3")Gravel & coarse sand grades out at 107'POORLY GRADED SAND, olive brown, dense, wet, fine to medium sand, 5-10% fines--------- ----- --"--- -----'. -.--'--- POORLY GRADED SAND, olive brown, dense, wet, fine to medium sand, 5-10% fines CLAY layer (2") iwth a 1.5" chert clast, stiff, low plasticity POORLY GRADED SAND, olive brown, dense, wet, fine to 117 122 BORING LOG PageNumber5'of 9

( 7 Consulting Engineers

& Geologists, Inc.-' j 812 West Wabash, Eureka, CA ph. (707) 41-8855 fax. (707)411-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING:; /186 Feet BGS DATE STARTED: 8/20/12 DATE COMPLETED:

8/30112 B3ORING LOG K13-4 2ft~)4AJ SAMP LE~0 W C a F I L- 22-J. IL 0 x) 51~0 , W 0U) q ) U) 0~~-_ _ _ _034 4 Bd-035 SM SP SP 127 t "5 0d-036 120 132 SP SP mediu-m sand, 5-10% fines POORLY GRADED SAND WITH SILT AND GRAVEL, olive brown to dark yellowish brown, dense, wet, fine to medium sand, 5% coarse sand, 10% fine gravel, well rounded, crude stratification, occasional gravels up to 1V, -10% fines---- --- ----------

-- ---POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines Grades to bluish black (GLEY 2 10B 2.511) at 123'POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines, massive POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines, massive POORLY GRADED SAND, olive brown, dense, wet, fine Bd-037 137 T 125 SP 0d-038 142 -t 130 SP SP BORING LOG Page Number 6 of 9 Consulting Engineers

& Geologists, Inc...U .1312 West Wabash, Eureka, CA ph. (707) 441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall PROJ. NUMBER: 012125 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB LOCATION:

Humboldt Bay Power Plant ELEVATION:

12 feet DIAMETER/DEPTH OF BORING: 186 Feet BGS DATE STARTED: 8/20/12 DATE COMPLETED:

8/30/12 BORING LOG KB-4 91r jR M\ L SAMPLE--z -J 6 0. 3 OI DESCRIPTIONRMAK

~~~~, 00 O I-~SI a.. -C0JU a Lu WW U U :3~I REMARKS 147 152 135-140 1 sand, 10% fines, slightly coarser sand constituent 157 t 145 POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines, slightly coarser sand constituent POORLY GRADED SAND, bluish black (GLEY 2 10B 2.511), dense, wet, fine to medium sand, 5-10% fines, massive POORLY GRADED SAND, bluish black (GLEY 2 10B 2.5/1), dense, wet, fine to medium sand, 5-10% fines, massive POORLY GRADED SAND WITH SILT AND GRAVEL, bluish black (108 2.5/1), dense, wet, 10-15% fines, fine to medium sand, coarse sand less common, 5-10% fine gravel (increases with depth)'SILTYSND WITH GRAVEL, bluish black, dense, wet, fine to mediumsand, 5-10% fines, subrounded gravel, -20%fines'SO/T, Bd-040 Bd-041 162 167 150 155 BORING LOG Page Number 7 of 9 Consulting Engineers

& Geologists, Inc.4t 812 West Wabash, Eureka, CA ph. (707)-441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: /186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/20/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

8/30/12 LOGGED BY: JPB BORING LOG KB-4 lLID F J Lv SAMPLE Z Z 0: SOIL DESCRIPTION a EAKS IL. -~9 a. lE 0 Wu Z_ _ _ 3 5 _ _ _r, 172 177 160 165 042*043 Bd-045 Bd-045 Od-.048 Bd-047 Ad-049 B&-040 Bd-'050 Bd-051 Bd-053 8d-064.Contact based on drilling performance 3" gravel clast in sampler WELL GRADED GRAVEL WITH SAND, dense, wet, fine to coarse A lot of fine gravel in cuttings Contact based on drillers comments (SILT/CLAY), show has SW with fine grave, rare light gray, very fine sand (SMIML) (bag sample)SILT, very dark greenish gray (GLEY 1 5GY 2.5/1), stiff to very stiff, moist, 5-10% sand, occasional shell fragments SILT/CLAY, very dark greenish gray, very stiff, moist, clayey and silty interbeds (crude), zones of abundant shell fragments SILT/CLAY, very dark greenish gray, very stiff, moist, clayey and silty interbeds (crude), less common shell fragments Interbedded silt, silt with sand (?) and clay, beds typically 0.25 to 1" thick 182 t 170 3.5 3.0 4.0 4.5 3.75 4.5>4.5* 4.0'3.5 4.0>4.5>4.5>4.5>4.5 24A4 25:6 11 17 187 175 BORING LOG Page Number 8 of 9 Consulting Engineers

& Geologists, Inc.42IT 812 West Wabash, Eureka, CA ph. (707)441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION:

Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION:

12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING:_ I DRILLING METHOD: Mud Rotary DATE STARTED: 8/20/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

8/30/12 LOGGED BY: JPB 86 Feet BGS BORING LOG KB-4 192 197 202 207 Grades to clayey with depth, same interbeds with predominately clay BORING LOG Page Number 9 of 9 I MKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX H SLURRY WALL HYDROLOGIC ASSESSMENT Page 1120

¶ j CONSULTING ENGINEERS

& GEOLOGISTS, INC.812 W. Wabash -Eureka, CA 95501-2138

° 707-441-8855

• FAX: 707-441-8877 .shninfo@shn-engr.com

Reference:

012125.100 August 15, 2012 Nicholas Gura, PE Kiewit Engineering Co.3555 Farnam Street Omaha, NE 68131

Subject:

Assessment of Hydrologic Impacts Associated With Slurry Wall Installation, Humboldt Bay Power Plant, Eureka, California

Dear Mr. Gura:

SHN Consulting Engineers

& Geologists, Inc. (SHN) herein presents our assessment of hydrologic impacts associated with the installation of a slurry wall in the Unit 3 area at Humboldt Bay Power Plant (HBPP), in Eureka, California (Figure 1). This study is a qualitative analysis based on review of existing data, completed reports, and historic groundwater monitoring activities.

A summary of historic groundwater flow conditions and our opinion on the impacts that the slurry wall installation would have on the hydrologic system is presented below.Slurry Wall Design-Basis for Assessment Installation of a slurry wall around the HBPP Unit 3 reactor caisson and spent fuel pool has been proposed to facilitate removal of the structures and provide a barrier to groundwater during excavation and dewatering activities.

The slurry wall will extend to a clay unit that is located at a depth of approximately 150 to 170 feet below ground surface (BGS) in the Unit 3 area. The plan view of the proposed slurry wall in relation to Unit 3 is shown on Figures 2 and 3, and a regional cross-section profile is shown on Figures 3 and 4.The slurry wall will be keyed into the Unit F Clay, which is believed to be a continuous 50-foot thick clay layer below the site. Preliminary soil borings are planned to verify the presence and thickness of this clay layer in the Unit 3 area. With the slurry wall embedded into the Unit F Clay, a complete barrier to groundwater will be formed, allowing dewatering to occur for excavation purposes.

The 2.5-foot thick slurry wall will have a circumference of approximately 680 feet, and a maximum width and length of 175 feet and 230 feet, respectively.

It is our understanding that once the Unit 3 subgrade structures are removed, the excavation will be backfilled and the upper 8 to 10 feet of the slurry wall will be breached to allow the flow of shallow groundwater.

Other than the modifications to the wall near the surface, it will be left in place indefinitely.

\ \Eureka\ Projects\

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PUBS\ rpts\20120815-HydroAssmt.doc Nicholas Gura Assessment of Hydrologic Impacts Associated With Slurry Wall Installation, Humboldt Bay Power Plant, Eureka, California August 15, 2012 Page 2 Stratigraphy Geologically, the Unit 3 area of HBPP is within the Hookton Formation, which is comprised of layered sedimentary alluvial deposits of silts, clays, sand, and gravel. The Hookton Formation has been informally divided into the Lower Hookton Formation and the Upper Hookton Formation.

Our compilation of subsurface data on the local and regional cross-sections is presented in Figures 3 and 4, respectively.

The First Bay Clay (surficial silt and clay terrace deposits) within the Upper Hookton Formation is widely reported as continuous across the HBPP site in the vicinity of Unit 3. The upper unit consists of interbedded silt, clay, silty clay, and clayey silt (fine grained sediments) that extends from near the surface (below any fill) to depths ranging from approximately 16 to 25 feet BGS in the Unit 3 area.The Upper Hookton sand beds, which are comprised of sand and gravel with discontinuous deposits of interbedded silt and silty sand, extends from below the First Bay Clay to a depth of approximately 60 feet BGS. The base of the Upper Hookton sand beds is marked by the Second Bay Clay, where present. Where the Second Bay Clay is not present, the Upper Hookton sand beds transition directly into the texturally similar deposits of the Lower Hookton Formation.

The Second Bay Clay is comprised of fine grained sediments and appears to be laterally discontinuous beneath the Unit 3 area. The Second Bay Clay has been identified to be 8 to 15 feet thick in the Unit 3 area, and may act as a localized aquitard, retarding the vertical flow of groundwater in these areas. The Second Bay Clay was encountered during recent drilling operations on the southern and eastern sides of Unit 3 at depths ranging from approximately 60 to 75 feet BGS. The Second Bay Clay was not recorded northwest of Unit 3.The Lower Hookton Formation consists of interbedded sand, silty sand, and gravelly sand encountered below the Second Bay Clay. The Lower Hookton Formation also includes a distinct, laterally continuous fine-grained unit termed the Unit F Clay (Woodward-Clyde Consultants, 1980)encountered at a depth of 150 to 170 feet below the HBPP.The Unit F Clay is an approximately 50-foot thick bed of fine-grained deposits recorded in early borings by Woodward-Clyde (1980) as consisting of silt, clay, silty clay, and clayey silt. Previous studies indicate the Unit F Clay to be present at a depth of approximately 150 to 170 feet BGS at the location of HBPP Unit 3 (PG&E, 2002). The Unit F Clay acts as a regional aquitard and is considered the lower limit of potential impacts from groundwater.

Aquifers For the purposes of this assessment, we considered the hydrologic impacts to the three aquifers above the Unit F Clay aquitard (within the upper 150-170 feet).\ \Eureka\ Projects\

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doc g Nicholas Gura Assessment of Hydrologic Impacts Associated With Slurry Wall Installation, Humboldt Bay Power Plant, Eureka, California August 15, 2012 Page 3 Underlying the Unit 3 area, the three distinct water bearing zones include: 1. groundwater in the Upper Hookton silt and clay beds generally within the First Bay Clay (upper 20 feet);2. groundwater within the Upper Hookton sand beds between the First Bay Clay and Second Bay Clay (approximately 20 to 60 feet BGS); and 3. groundwater within the Lower Hookton Formation between the Second Bay Clay and the Unit F Clay (approximately 60 to 160 BGS).Currently, there are monitoring wells installed into each of these three aquifers for the HBPP radiological environmental monitoring program (REMP) that are monitored on a quarterly basis.Groundwater Flow Groundwater flow within the above-described aquifers is influenced by laterally variable stratigraphy; nearby faults; site infrastructure, including the deep subgrade structures; and the site's proximity to Humboldt Bay. Previous studies have documented strong tidal influence within the two primary aquifers at depth, the Upper Hookton aquifer and the Lower Hookton aquifer, as discussed in SHN's hydrogeologic assessment report (SHN, March 2010). The groundwater within the upper silt and clay beds does not appear to be tidally influenced.

In order to develop an overall groundwater flow direction, SHN conducted two tidal influence studies within the Unit 3 area, once in October 2010 (dry season) and again in March 2011 (wet season) (SHN, 2011). Pressure transducers in eight of the existing Unit 3 area monitoring wells were used to record groundwater elevations over three complete tidal cycles (approximately 74 hours8.564815e-4 days <br />0.0206 hours <br />1.223545e-4 weeks <br />2.8157e-5 months <br />) during each study.The results of these studies are discussed in a Tidal Influence Study of Unit 3 Area, Humboldt Bay Power Plant, Eureka, California dated July 2011 (SHN, 2011). Findings and conclusions relevant to this slurry wall impacts assessment include:* Tidal influence on the Upper Hookton aquifer causes cyclic reversals in the groundwater flow direction during tidal cycles. Flow direction is to the south (inland) at high tide and to the north (bayward) during low tide.* Tidal influence on the Lower Hookton aquifer causes variations in the groundwater gradient (and flow rate); however, flow direction appears to be consistently toward the northwest (bayward).

• The vertical flow gradient between the Upper and Lower Hookton aquifers is upward in the southern portion of the Unit 3 area (where the Second Bay Clay is present), and flat to downward in the northern portion of Unit 3, (where the Second Bay Clay is not present)." Using estimated values for effective porosity and hydraulic conductivity, groundwater net flow velocity is nearly zero within the Upper Hookton aquifer (no discernable flow direction), and from 6 to 17 feet per year toward the bay within the Lower Hookton aquifer.\ \Eureka\ Projects\

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PUBS\ rpts\20120815-HydroAssmt.doc Nicholas Gura Assessment of Hydrologic Impacts Associated With Slurry Wall Installation, Humboldt Bay Power Plant, Eureka, California August 15, 2012 Page 4 The most significant finding from the tidal influence study is that groundwater gradients continuously fluctuate in both direction and magnitude, but the net groundwater flow velocity within the Unit 3 area generally is very low and in a bayward direction.

Impacts to Hydrologic Conditions The primary impact of the slurry wall will be its alteration of localized groundwater flow.Groundwater will be forced to flow around the slurry wall. In a simplified groundwater model in which a cylindrical barrier is placed in the ground, water flowing through the subsurface mounds on the upstream side of the structure, and a stagnation area or low point forms on the downstream side. Groundwater flow velocity may increase around the lateral margins of the structure where the groundwater gradient would be highest.As discussed, two main water-bearing zones will be impacted:

groundwater flowing within the Upper Hookton sands and the Lower Hookton sands. The discontinuous nature of the water-bearing deposits in the Upper Hookton fine-grained deposits (First Bay Clay) limits lateral flow, and is already modified by the below-grade infrastructure of Unit 3. SHN does not expect that the slurry wall will significantly change the existing conditions in the Upper Hookton formation fine-grained deposits.Based on the 2010/2011 tidal influence study, the net groundwater flow velocity within the Upper Hookton aquifer is nearly zero, with no discernable flow direction.

With a low to negligible flow velocity, the impacts to groundwater flow from the slurry wall are expected to be negligible.

Based on the 2010/2011 tidal influence study, the net groundwater flow velocity within the Lower Hookton aquifer ranges from 6 to 17 feet per year (0.02 to 0.05 feet per day) toward Humboldt Bay.This flow velocity is low and it is expected that the slurry wall will cause only minimal localized impacts to regional groundwater flow.The slurry wall will be a barrel-shaped barrier within the regional aquifer that will not cut off or inhibit groundwater movement.

Highly transmissive deposits in the Upper and Lower Hookton Formations (predominantly sand) allow relatively easy groundwater flow. The area is influenced by tidal changes, currently exhibits very low groundwater velocity, and is recharged by Humboldt Hill, Buhne Point and Humboldt Bay.Generally, the alignment of the structure is parallel to groundwater flow direction and won't preclude, groundwater from flowing around it. Groundwater that may mound on the upstream side of the slurry wall or stagnate on the downstream side would be minimal due to tidal influence on the Unit 3 area from Humboldt Bay.Limitations The findings and conclusions presented herein are based on a study of inherently limited scope.Our interpretations are based on previous studies and site conditions that are known to us at the time of our study. The analyses and conclusions contained in this report are based on our current\ \Eureka\Projects\2012\012125-HBPPSlurryWaIl\100-HydologAssess\

PUBS\ rpts\20120815-HydroAssrnt.doc J;2 Nicholas Gura Assessment of Hydrologic Impacts Associated With Slurry Wall Installation, Humboldt Bay Power Plant, Eureka, California August 15, 2012 Page 5 understanding of proposed slurry wall installation project We have assumed that the information obtained from previous subsurface explorations is representative of subsurface conditions throughout the site.If the scope of the proposed slurry wall construction, including the proposed location, depths, or final state changes from that described in this report, our recommendations should also be reviewed.

No representation, express or implied, of warranty or guarantee is included or intended.If you have any questions please call me at 707-441-8855.

Sincerely, SHN Consulting Engineers

& Geologists, Inc.Erik J. Nielsen, PG, CHG Project Manager EJN:lms HG i.7.62 Attachment

1. Figures ....... ." References Cited Pacific Gas & Electric Company, Geosciences. (December 27, 2002). Technical Report TR-HBIP-2002-01, Seismic Hazard Assessment for the Humboldt Bay ISFSI Project, Revision 0. NR:PG&E.SHN Consulting Engineers

& Geologists, Inc. (March 2010). Tidal Influence Study of Unit 3 Area, Humboldt Bay Power Plant, Eureka, California (July 2011). Eureka:SHN.

Woodward-Clyde Consultants.

(1980). "Evaluation of the Potential for Resolving the Geologic and Seismic Issues at the Humboldt Bay Power Plant Unit No. 3." Unpublished consultants report for PG&E. NR:Woodward and Clyde.\\Eureka\Projects\2012\012125-HBPPSIurryWal\

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PUBS\ rpts\ 20120815-HydroAssmt.doc Attachment 1 Figures J 1,30 fvoiA AIMIf *i IC/'I,//N V/l 59 i ,!0.v V.,\V~ ~-5. ,~it;-- ,\ A~~ / .1 1'.' (!SWXRVE.* aiUi' AND FlAUS' LANDINVG U/SGS 7.5 MINUTE 0U40R4M113E

~. I 1-JooO~*5 Pacific Gas & Electric Site Location Map Humboldt Bay Power Plant Consulting Engineers Eureka, California SHN 012125& Geologists, Inc. July, 2012 012125-SITE-LCrN Figure 1 I I SOURCE GO3XLE E4IWH /AWE (SEPT 2(K?) M PLA AGM Pacific Gas & Electric Aerial Photo View of HBPP Humboldt Bay Power Plant with Site Features Eureka, California SHN 012125 Consulting .Ie1 012125-ARAL Figure 2& Geolo issInc. May2011 I 022 -E I LI Fg r AET~UMTJ f V017PA3T 1 15r BAY"AV i ýA# Eow F 2 0 CROSS SECTION LINE A WELLS RELATIVE TO UN1 1"6100, KEY TO MOWNITRNGW TTND w 4iI hVNamI 2 I 2 0 j 0 0 g I M AR4AT (2")EXPLAMAiTIO MWI~-MOW-2 MOW-4 MOW-9 (ASWDAWm)AO-W-11 UITHOLOGY:

E RYR FO RNED -EWDS/ W7 ERVY LOW PMVLRWC/Y*A 6RA4 4?NE SEDMil-A00DEMMTO 1 LOW PERMM&WUY KRY M~W PMH E W WLI7 r -1 77INY LAMIM~ DVV/7Y L J aREN AL7EhMW77P SIUlY & SAPDY SYMBOLS: sL 7 FlME- OR DRE5RL0Wr7?Y

-Lmonto=r coiffrcr QUM" WA MAMREEN INTEWA OF 5t'UOE P54 IIPMT (2"Q)LW)UJA.M DEPWh m LOCATION OF A-A' RELATIVE TO REGIONAL SETTING Engineers sts, Inc. July, 2012 Pacific Gas & Electric Humboldt Bay Power Plant Eureka, California Geologic Cross Section A-A'with Proposed Slurry Wall SHN 012125 Consulting F& GKologi I 012125 XSEC1-5B I Figure 3 I 012125-XSEC I -BB I Figure 3 SM*100 a -L* -US 0 WS n 3D N W0 M0 W0 WS M 10 USI 125 VA IM 1 70 U 4 ai lid MS US 20 M M. WO W W US MS W. MS M M M -M M M 40 4 40 40 a 4Wa SOURML FSAI? UAU47E (2006)LOCATION OF A-A' RELATIVE TO REGIONAL SE1TING Consulting n gineers& Geologsts, Inc.Pacific Gas & Electric Humboldt Bay Power Plant Eureka, California Regional Cross Section with Proposed Slurry Wall SHN 012125 IJu.ly, 2012 1 la~y, 2012 I mn25-xsEc~r-aBI iur3 I Figure 4

-lOKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report APPENDIX I EXCAVATION MATERIAL FLOW DIAGRAMS AND TABLE Page 1131 Slurry Wall Excavation in Weeks Week 1 Week 2 200 , Week 3 10000 CY Slur.Ex.....

Week 4-17 1000 CY Slurry Exc.1000 CY Slurry Exc.Week 18 Week 19 Week 20 Week 21 3000 CY... .......................................

.......................... .............. ........... ..... ... .................

........... ................

...... ..............

200 C 1000 CY 1000 CY Offsite Caisson Excavation Stockpile Based on 25 Intermodal Load-out/Week Lift I Weeks 1-4 Lift 2 Weeks 5-8 rnhtV flr fly 1000 CY Load-out to Intermodal Week' fo-e. to.............*0 1000 CY Load-out to Intermodal pared to be tamnatedj rProcess Continues Per Spreadsheet

Week' ':Results

:'

................. ......;. , -.1" ..1.2.1.12'

.1 .2 '.. .: 2" .. .............. ...Lift 10 Weeks 37-40 1000 CY Load-out to Intermodal Lift 3 Weeks 9-12.600C t W ....................Wee...1......t...

......................We.......o...to S.... ............l.i Lift 4 Weeks 13-16 800 C Lower Lift 5 (LL5)Weeks 65-70 200 S I F 1000 CY Load-out to Intermodal Wek~k 16-: Jhoe )Ito....li::::i A poWpriate.........:.. ..........................I* .. ... .. .. ... x x .x .: ........, .:.:.:.:..

...... ...W ee. ..........

..eek. ....ol W eek..... ....,.t....oae : .......................I Table 6 -Excavation Schedule Phase 1 Upper Caisson Lift 1-10 El +(121 to El -(30) Lift 1 (4 Weeks) Lift 2 (4 Weeks) Lift 3 (4 Weeks) Lift 4 (4 Weeks) ift 5 (4 Weeks) Lift 6 (4 Weeks) Lift 7 (4 Weeks) Lift 8 (4 Weeks) lift 9 (4 Weeks) Lift 10 (4 Weeks)_tart Finish Stan Finish rst-, T e F-sh .. sh stko I Fnih St....s kFinih Stan I Finish 8F...r n I Frsk Finih Startk Finish Elevation 12 6 6 2 2 --2 6 10 1 14 1 18 22 7 26 -30 C.Y Removed (Avg) 1020 BCY X 1.2 Swell Factor 1200 1200 1200 1200 1200 1200 1200 1200 1200 1200 Running Total 1200 2400 3600 4800 6000 7200 8400 9600 10800 12000 RunningWeeks 1 I 9 12 03 16 17 20 21 24 25 20 29 32 93 36 37 1 40 Neek Count for PG&E estlCkaracterization Results 3 7 11 10 19 2339/We"ek/lift 0 0 0 0 0 0 0 0 0 0 20/Week/Lift 200 400 600 800 1000 1200 1400 16 1800 2000 20/Week/Lift 400 800 1200 1600 2000 2400 2800 3200 3600 4000/Wee /Lift 600 1200 1800 2400 3000 3600 4200 4600 5400 6000 Phase 2 Lower Caisson Lift 1-5 EL -(30) to El -(80) Lower Lift 1 (6 Weeks) Lower Lift 2 (6 Weeks) Lower Lift 3 (6 Weeks) Lower Lift 4 (6 Weeks) Lower Lift 5 (6 Weeks) Weeks to deplete QTY_________

...._ __ F olsh_ Finishth tsh Star Finish Elevation 4- 4 8 6 73 -80 CY Removed (Average) 560 1960 1820 1680 980 Running Total 12060 14520 16340 18020 19000 Running Weeks 41 1 46 47 52 53 54 65 70 Week Count for PG&E est/Chakrateriat ion Results 43 49 5561 67 O/Week/Lift 0 160 0 60 0 0 5/Week/Lift 1060 1520 1040 2020 1500 6 0/Week/Lift 3360 4120 4740 5220 5000 25 lS/Week/Lift 5660 6720 7640 6420 8 0SUO Phase 1 Upper Caisson Lift 1-10 El +(12) to El -(30) Lift 1 (4 Weeks) Lift 2 (4 Weeks) Lift 3 (4 Weeks) Lift 4 (4 Weeks) Lift 5 (4 Weeks) Lift 6 (4 Weeks) Lift 7 (4 Weeks) Lift 8 (4 Weeks) Lift 9 (4 Weeks) Lift 10 (4 Weeks)Start FIn Finish St .F -sh Start2 Finish- Start Fs sh s sh -s 2 Finish C.Y Removed (Avg) 1020 BCY X 1.2 Swell Facor 1200 1200 1200 1200 1200 1200 1200 1200 1200 1200 1200 2400 3600 4800 6000 7200 8400 9600 10800 12000 Running Weeks 1 14 5 T 8 9 12 13 16 17 20 21 24 2 28 29 32 33 36 37 40 Week Count for PG&E Test/Charauoerization Results 3 7 11 15 19 23 27 31 35 39 30/Weelift 0 0 0 0 0 0 410 0 0 0 25/Week/ift 200 400 600 000 1000 120 1400 1600 100 2000 20/Week/LUft 400 000 1200 1600 2000 2400 2800 3200 3600 4000 15/Week/Lft 600 1200 1800 2400 3000 3600 4200 4800 5400 6000 Phase 2 Lower Caisson Lift 1-5 E L -(30) to El -(80) Lower Lift 1 )6 Weeks) Lower Lift 2 (6 Weeks) Lower Lift 3 (6 Weeks) Lower Lift 4 (6 Weeks) Lower Lift 5 (6 Weeks) Weeks to deplete QTY Start. I Finish s .... I Finish _t___ Firntis Stern Start I Finish Elevation

-301 44 -481 6_73 -3 8 C.Y Removed )Average) 560 1960 1820 1680 980 Running Total 12560 14520 16340 18020 19000 Running Weeks 41 46 47 2 3 5 64 65 70 Week Count for PG&E Test/Characterization Results 43 49 55 61 67 30/Week/Lift 0 160 180 60 0 0 25/Week/Lift 1000 1520 1040 2020 1500 6 20/Week/Lift 330 4120 4740 5220 5000 25 15/lWeek/Lift 5660 6720 7640 8420 8500 57