Text

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)
	v • d • e

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 .................................................................................................................................... iv 1.0 Executive Sum m ary ................................................................................................................................. 1 1.1 Project Description .............................................................................................................................. 1 2.0 Technical Challenges ............................................................................................................................... 2 2.1 Slurry W all Construction ..................................................................................................................... 3 2.2 Soil Stockpile Areas ............................................................................................................................. 3 2.3 Below Grade Obstructions .......................................................................................................... 4 2.4 As-Built Plans ....................................................................................................................................... 4 2.5 Lim its of Contam ination ...................................................................................................................... 4 3.0 Scope 1 Caisson Rem oval Engineering .............................................................................................. 5 3.1 Concept Developm ent ........................................................................................................................ 5 4.0 Caisson Excavation System ............................................................................................................ 6 4 .1 Slu rry W a ll ........................................................................................................................................... 7 4 .2 So il Na il Wa 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 ................................................................................................................... 11 5 .3 Slu rry W a ll ......................................................................................................................................... 12 5.4 Dewatering ........................................................................................................................................ 13 5 .5 So il Na il W a ll ..................................................................................................................................... 13 5.6 Sheet Pile W all .................................................................................................................................. 13 5.7 Settlem ent ......................................................................................................................................... 13 5.8 Construction Vibration Analysis ................................................................................................... 17 6 .0 Sa fe ty .................................................................................................................................................... 18 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 ....................................................................................................................... 19 7.1 PG& E Site Preparation W ork Prior to Slurry Wall Construction ................................................... 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 ....................................................................................................................... 23 9.3 Caisson Excavation ............................................................................................................................ 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 ................................................................... 31 16.0 Schedule .............................................................................................................................................. 32 17.0 References .......................................................................................................................................... 32 17.1 Historical Docum ents ...................................................................................................................... 32 17.2 Engineering References .................................................................................................................. 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 List of Abbreviation:

AISC American Institute of Steel Construction Lmax Maximum Sound Level ACI American Concrete Institute LRW Liquid Radwaste ALARA As Low as Reasonably Achievable LSA Low Specific Activity ANSI American National Standards Institute MDA Minimum Detectable Activity ASME American Society of Mechanical Engineers mCi/ml Microcuries per Milliliter NEHRP National Earthquake Hazards ASTM American Society for Testing and Materials Reduction Program National Institute of Standards and bgs Below Ground Surface Technology 2

Bq/m Becquerel per Square Meter NRC Nuclear Regulatory Commission BSL Background Screening Level NUREG NRC Reports OSHA Occupational Health and Safety CALTRANS California Department of Transportation Administration CCC California Coastal Commission PCB Ploy Chlorinated Biphenyl CEQA California Environmental Quality Act PCM Personal Contamination Monitor CFM Cubic Feet per Minute PCF Per Cubic Foot CFR Code of Federal Regulations PGA Peak Ground Acceleration CLSM Controlled Low Strength Material PG&E Pacific Gas & Electric Company COPC Constituent of Potential Concern pCi/g Picocuries per Gram cy Cubic Yards PPE Personal Protective Equipment Cs-137 Cesium -137 PSF Per Square Foot dBA A - Weighted Decibel PSI Per Square Inch DCGLs Derived Concentration Guidelines QA Quality Assurance DOT Department of Transportation QC Quality Control Qualified Storm Water Pollution DTSC Department of Toxic Substances Control Prevention Plan Developer elev. Elevation RAM Radioactive Material FHWA Federal Highway Administration RB Radwaste Building FSAR Final Safety Analysis Report RBL Radionuclide Background Level GWTS Groundwater Treatment System RCNM Roadway Construction Noise Model RCRA Resource Conservation and gpm Gallons per Minute Recovery Act HASP Health and Safety Plan REM Roentgen Equivalent Man HBGS Humboldt Bay Generating Station RFB Reactor Fuel Building HBPP Humboldt Bay Power Plant RP Radiation Protection HSC Health and Safety Code SAFSTOR Safe Storage IBC International Building Code SCO Surface Contaminated Object IM RAO Interim Measures Removal Action Objective SFP Spent Fuel Pool PG&E's Humboldt Bay Power Plant IM/RAW Draft Interim Measures Removal Work Plan Site located at 1000 King Salmon Avenue, Eureka, California ISFSI Independent Spent Fuel Storage Installation SPT Standard Penetration Test KG Kilogram SVOC Semivolatile Organic Compound LFO Liquid Fuel Oil TN Transnuclear, Inc.

LLMW Low-level Mixed Waste TPH Total Petroleum Hydrocarbon LLRW Low Level Radioactive Waste 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.

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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.

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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 0.00278 hours 1.653439e-5 weeks 3.805e-6 months 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 0.00278 hours 1.653439e-5 weeks 3.805e-6 months 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 0.00333 hours 1.984127e-5 weeks 4.566e-6 months 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.

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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.

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IfOKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report

.*.l .*ennp_ 1 Cai.*.nn 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.

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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 support system include the following:

S Control and maintenance of dewatering during excavation; 0 Reliability of containment system; and, S 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:

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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.

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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.

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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.

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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

iHBPP Caisson llOKiewit 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.

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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.

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1OKiewit HBPP Caisson Removal Feasibility Study 100% Draft Feasibility Report Plads Output Vesion 2010.0.0.5880 ~in I

-40.00 OM 40.00 $0.00 120.00 160.10 2001.00 240.00 200.00 200.00 175.00 150.00

'2600 160.00 100.00 75.00 50.00 120.00 25.00 000

-2500 80.00 -4 -50.00

-75.00

-100M00 40.00"-j

-12500

-150.00 Y -175.00

-200.00 40.00o

-225.00 Total displacements u y Maximum value = 0.1888 ft (Element 88 at Node 44)

Minimum value = -0.2116ft (Element 349 aWNode 225) =2.5 in I PLAXISi

_ __

kt 012 9-13-2012 51 IKiewit Corporation 9/19/2012 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 20.00

~2.5 in 0.00

-20.00 100.00- L3T4.. 40.00

-60.00

-80.00

-100.00

-120.00 120.00

-140.00

-180.00

-180.00 80.00- -200.00 U20.00

-240.00

-2M000 40.00- -29D.00

-20000 Y -320.00 0.00 - -40.00

-3*200 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.

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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 . -- I--1Ebedded 1.lb 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- 2Ton Drop Batl, 40 ft Drop

00 Caisson Drilling & Large Dozer

-X- Trucks UX

-X -Cranie Idling

... 0 Dacamage Trese eiet 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.

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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.

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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 NRC.

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.

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@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.

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@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

! *Kiewit 0

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.

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@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.

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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.

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.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.

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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, 1st Ed.

" Construction Induced Movements of In-Situ Walls. Clough, Wayne G. and O'Rourke, Thomas D.

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@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.

DISCLAIMER:

THU INFORAI ON*DOITAINED HRiýN I INTRNDED AS A VROOF OF AND IS DMONSHA IN NATURE.L rr SHALL NOT M CONSTRUED AS CONYMNIMSK ALL NECUGSART IRFORIATIONR EQUIANWOTO PUOFORCHS THlE WOIRKL.CNRO SML - REPO9NSLE "O INDEFMENDENTLTyVALIDATING ALL ELEMUNWTSOF DUIDiN AND PROVIDING ALL NEGHUSRND EiNEERING NECESSAR TO SUIT ITS KIEWIT PLAZA OMAHA, NE 66131 OWN MISLANSAND MErHODS4 FOR EXECUrTING THE WO1E.

GRND GROUND HCL HORIZONTAL CONTROLUNE ABV ABOVE HORIZ HORIZONTAL ADJ ADJJST/ADJUSTABLE 10 INSIDEDIAMETER ALT ALTERNATE IE INVERTELEVATION INV INVERT DETAIL INDICATOR ALUM ALUMINUM ANCH ANCHOR/ANCHORAGE JOT JOIST JT JOINT SHEETI FRO - SECTIONOR DETAIL APPROX APPROXIMATELY S AT K KIP-1OOS WHICHSECTION (.-,;--/SHEET I WHERE AVG AVERAGE KSI KIPS PER SQUAREINCH OR DETAILIS CUT-t'j'i SECTIONOR DETAIL BEL BELOW ANGLE CAN RE FOUND BLDG BUILDING +/- PLUS OR MINUS BLK BLOCK LOS POUNDS BM BEAM LO LONG BOc BOTTOM OF CONCRETE LLH LONGLEG HORIZONTAL ROT BOTTOM LLV LONGLEG VERTICAL SHEET INDEX RON BOTTOM OF WALL MAX MAXIMUM O. IDRmAlWIN SUBJECT BP POINT BASE PLATE/BEGIN MECH MECHANICAL BRO BEARING MFR MANUFACTURER GENERAL BRKT BRACKET MIN MINIMUM I SHEETINDEX RTWN BETWEEN MISC MISCEL EOUS NO. NUMBER 2 GENERAL NOTES BVCE BEGINVERTCURVEELEV BVCS BEGINVERTCURVESTATION NTS NOT TO SCALE 3 GENERAL ARRANGEMENT PLAN BW BOTHWAYS Oc ON CENTER 4 SITE USE PLAN Cc CENTERTO CENTER OO OUTSIDE DIAMETER OPNG OPENING STORM,SEWER.WATER.& OIL UTILITIES PLAN CAJS CAISSON CAP CAPACITY *t PLATE , ELECTRIC& TELECOMMUNICATION UTILITIES PLAN

,_ CENTERLINE PLC PROGRAMMABLE LOGISTICS CONTROL SLURRY WALL CF CUBICFEET PC PRECAST PERP PERPENDICULAR 6 SLURRYWALLSTE USE PLAN CHAN CHARNEL CJ CONTROL JOINT PI POINTINTERSECTION 7 SLURRYWALLAUGNMENT PLAN CLG CEILING PLF POUNDSPER LINEARFOOT B INSTRUMENTATION & DEWATERING PLAN CLR CLEAR PLWD PLYWOIOD COG CENTEROF GRAVITY PNL PANEL 9 TYP ELEVATION & SECTIONS COL COLUMN PPM PARTS PER MILLION PSF POUNDSPER SQUAREFOOT 10 STORMWATERPREVENTION PLAN CONC CONCRETE CONN CONNECTION PSI POUNDSPER SQUAREINCH STORIMWATlrwR CONST CONSTRUCTION PVI POINT OF VERTINTERSECT 11 STORMWATERPREVENTION PLAN(BY OTHERS)

CONT CONTINUOUS R RADIUS CONTR CONTRACTOR RCSC RESEARCHCOUNCILON STRUCTURAL CONNECTIONS 12 STORMWATERPREVENTION DETAILS(BY OTHERS)

CTR CENTER REINP REINFORCEMENT SOIL NAIL WALL CU FT CUEICFOOT REQU REQUIRED REV REISION 13 !SOILNAILWALLELEVATION & DETAILS CU TD CUBICYARD B DIAMETER SCHED SCHEDULE 14 ISOIL NAILWALLDETAILS DBL DOUBLE SF SQUAREFOOT SHORING AND EQUIPMENT SUPIPORT DEG DECREE SiM SIMILAR SPA SPACING 15 DEMOLITIONEQUIPMENT SUPPORT DEMO DEMOUSH/DEMOUTION DIAG DIAGONAL SPECS SPECIFICATION iN ISHEETPILE & RING BEAM STA STATION DN DOWN OWG DRAWING STD STANDARD STIFF STIFFENER EA EACH STl STEEL EL ELEVATION EMNED EMBEDMENT ST STREET SWL SAFE WORKING LOAD ENGR ENGINEER T&B TOP AND BOTTOM EP END POINT EO EQUAL TBD TO BE DETERMINED EQUIP EQUIPMENT THK THICK/ THICKNESS EVES END VERTCURVESTATION TOG TOP OF CONCRETE EVCE END VERTCURVEELEV TOP TOP OF FOOTING EW EACH WAY TOP TOP OF PIER EXIST EXISTING TOS TOP OF STEEL ECP EXPANSION TOW TOP OF WALL FF FINISHFLOOR TYP TYPICAL FLG FLANGE UNO UNLESSNOTEDOTHERWISE FND FOUNDATION VERT VERTICAL FT FOOT W/ WITH FTG FOOTING W/O WITHOUT CA GAUGE WD WOOD GALV GALVANIZED GOVT GOVERNMENT PRINT IS ONE HALF INDICATED

GEER AL NOTES E. SO(L NAILS:

J,, GROUT: TYPEII CEMENT,4.0DD PSI MIN,8 INCH MIN1MUM SLUMP.WATERTO CEMENTRATIO(W/C) SHALLNOT

1. ALLDIMENSIONS AND ELEVATIONS ARE IN DECIMAL FEETUNLESSNOTEDOTHERWISE EXCEED0.45 BY WEIGNT FOR GROUT. MINIMUM 3 DAY COMPRESSIVE STRENGTH - 1,000 PSI.

2. CONTRACTOR IS RESPONSIBLE FOR OBTAINING ALLREQUIRED PERMITSASSOCIATED WITHTHE WORK BARS: Fy-,75 KSI (GRADE75), CONFORMING TO AS'TM A615.

3. CONTRACTOR SHALLPROVIDEAN OSHAAPPROVED FALL PROTECTION SYSTEMWHERENEEDED SOILNAILASSEMBLY HARDWARE. INCLUDING BEARINGPLATES.NUTS. AND WASHERS:Fy=36 KSI

4. BASE TOPOGRAPHIC. SITE. AND UTILITYPLANS WEREPROVIDED BYPG&E. NORTHING AND EASTING COORDINATES ARE BASED F 4. LAYOUT OF SOIL NAILSTO BE PERFORMED BY THE CONTRACTOR BASEDON THE DEVELOPED ELEVATIONS AND ON NADB83. ELEVATIONS AREBASED ON NAVD8X. TYPICAL SECTION. ADAJSTNENTS MAY BE MADETO ACCOMMODATE FIELDCONDITIONS AS APPROVEDBY THE

5. CAISSONDIMENSIONS AND SECTIONSARE BASEDON THE UNIT3 REACTOR CAISSON VERTICAL SECTIONS - SHEET#55428 ENGINEER.

REV8. THE UNIT3 FUEL PIT AREA PLANS AND SECTIONSARE BASEDON SHEET f55433 REV 4. UNIT3 TURBINE BUILDING E.5. TOTALLENGTHOF TESTSOILNAILS EQUALSEMBEDMENT LENGTHPLUS EXTRALENGTHREQUIRED FOR JACKING FOUNDATION PILES LOCATION. TIP,AND CUTOFFELEVATIONS ARE BASEDON SHEET #55420 FOUNDATIONS PILUN PLAN EQUIPMENT

6. CONTRACTOR SHALLSUBMITPROPOSEDCONCRETE DESIGNMIX WITHTESTRESULTS TO THE ENGINEERFOR REVIEW AND EN6. TESTINGOF ALLSOIL NAILSSHALLBE PERFORMED IN ACCORDANCE WITHFHWASOILNAI. MANUAL CONTRACTOR APPROVAL IS RESPONSIBLE FOR PROVIDING TESTAPPARATUSAND LOADINGJACK.

7. REINFORCING STEELSHALLBE NEW BILLETSTEELCONFORMING TO THE REQUIREMENTS OF ASTT A-61T GR 60 UNLESSNOTED E.7. PROOFTESTING SHALLBE PERFORMED ON 5D OF THENAILS INSTALLED AND VERIFICATIONTESTINGSHALLBE OTHERWISE PERFORMED ON AT LEASTFOUR SACRIFICIAL TESTNAILS B. BACKFILLSHALLCONFORMTO THE REOUIREMENTS STATEDIN THE CONTRACTSPECIFICATIONS F.B. THE MAXIMUM UNSUPPORTED VERTICAL CUT SHALLNOT EXCEED5 FEETUNLESSAPPROVALIS GIVENBY THE

, COORDINATES ARE PROVIDED FOR SURVEYLAYOUT PURPOSES ENGINEERFOR A TALLER CUT. WALLFACE EXCAVATION SHALLNOT PRECEDETHE INSTALLATION OF NAILS BY

10. STRUCTURAL STEELSHALLBE THE FOLLOWING TYPE/ GRADE: MORE THAN48 HOURSWITHOUT THE PRIOR APPROVALOF THE ENGINEER.

A. STRUCTURAL STEEL.EXCEPTAS NOTED,SHALLBE ASTMASS Fy-SUKSIOR BETTER F. TERETEFACING:

TI. WELDING REINFORCED SHOTCRETE:

A. ALL WELDSSHALLBE WITH70 KSI ELECTRODE PER AWS DI.1 A Fy (REBAR)- 60 ESI

12. BOLTS F.3. Fy (WRIN)= 65 KSI A. BOLTS SHALLBE A325 SR BETTERUNLESSNOTEDOTHERWISE FA. F'c = TYPE II CEMENT,4.000 PSI (28 DAY COMPRESSIVE STRENGTH)

B. BOLTS SHALLBE USED IN ACCORDANCE WITHRCSC SPECIFICATION FOR STRUCTURAL JOINTSUSINGASTVFA325 OR FT.S WATERTO CEMENT(W/C) RATIOSHALLNOT EXCEED0.45 BY WEIGHT FOR SHOTCRETE A490 BOLTS FA. MINIMUM SHOTCRETE COVERMEASURED FROMTHE FACE OF SHOTCRETETO THE FACE OF ANYREINFORCING BAR C. BOLTHOLESSHALLBE NORMAL SIZE PER RCSC SPECIFICATIONS UNLESSNOTEDOTHERWISE OR WIRESHALLBE 1.5 INCHES.UNLESSOTHERWISE NOTED

0. LONGTHREADED BOLTS SHALLBE ASTMF1554 GR 105 OR BETTER E. J BOLTSSHALLBE ASTIAF1554 GR 36 OR BETTER G. STRUCTURAL OBSERVATION AND SPECIALINSPECTION

13. $J.3RRYWALL G.1. CONTRACTOR SHALLALLOW FOR UP TO ONE WEEKPER LEVELOF SOILNAILS FOR FINALSITE SURVEYBY PG&E.

THISSHALLBE ACCOMPUSHED SUCH THATEXPOSEDSOILSLOPESARE NOTEXPOSEDFOR MORETHAN48 HOURS S(A HALL BE A CEMENTBENTONITE MIX WITHA MINIMUM AVERAGEPERMEABILITY OF 1X10-6 CM/SEC AND A MINIMUM BEFORESOIL NAILSARE INSTALLED.

UNCONFINED COMPRESSIVE STRENGTH OF 20 PSI AT 28 DAYS. CONTRACTOR TO PROVIDEMIX DESIGNSTO PG&EWITH G.2. PG&E QUALIFIED REPRESENTATIVE SHALL.

LABORATORY TESTINGRESULTSPRIOR TO BEGINNING SLURRYWALL CONSTRUCTTON. G.2.1. OBSERVEALL SOILNAILHOLESBEFOREGROUTOR SHOTCRETEIS PLACED B. SLURRYWALLCONTRACTOR TO PROVIDESC PLANFOR SLURRYWALLTO PORE FOR APPROVAL G.2.2. INSPECTALL REINFORCEMENT PRIOR TO PLACEMENT OF SHOTCRETE C. SLURRYWALLCONTRACTOR IS RESPONSIBLE FOR PRE-TRENCHING THE SLURRYWALLAUGNMENT TO EL -3 AND G.3. THE ENGINEERSHALLOBSERVEAND EVALUATE ALL EXCAVATIONS TO ASSESS WHETHER THE GEOLOGIC CONDITIONS INCLUDES AREREPRESENTATIVE OF THOSEASSUMEDIN THE DESIGN C.1. REMOVAL OF ALL NON-ESSENTIAL AND COLDAND DARKUTILITIES WITHIN10.0' OF THE SLURRYAND REMOVAL OR G.4. THE ENGINEERSHALLPERFORM FULL TIMECONSTRUCTION OBSERVATION OF:

RELOCATION OF OVERHEAD ELECTRICLINESWITHIN 20OD'OF THE PROPOSED SLURRYWALLALIGNMENT G.4.1. SOIL NAILDRILLING C.2. REMOVAL OF CONTAMINATED SOILAND BACKFILLING THE EXCAVATION WITHCLSM. OPEN UTILITY CONDUITS. PIPE. G.4.2. ALL THREADBAR INSTALLATION TUNNELS,ETCSHALLBE CAPPEDAND/OR FILLEDWTH CLSM G.4.3. GROUTING CA3. PROTECT.TEMPORARILY SUPPORTAND/ORRELOCATE ESSENTIALUTILITIES SERVICING UNIT 3 SUCHAS H. THE ENGINEERSHALLBE NOTIFIESTO OBSERVEALL SOIL NAILTESTING ELECTRICAL. WATER, MAINPLANTEXHAUST SYSTEMAND COMMUNICATION 1. THE CONTRACTOR SHALLNOTIFYTHE ENGINEER48 HOURSPRIOR TO REQUIRED OBSERVATION/INSPECTION CA,. REMOVAL OF FOUNDATION PILES AND CONCRETE SLABS FROMUNIT2 THAT ARE ALONGTHE SLURRYWALL 17. SHORING t

AUGNMENT A* " CONCRETESHALLBE P'c - 5,000 PSI

14. DEWATERING REINFORCING STEELSHALLBE ASTMA61TS GR. 60, BAR BENDS PER ACI STANDARDS A. DEWATERING WELLINSTALLATION AND ABANDONMENT SHALLBE PERFORMED. AT A MINIMUM. IN ACCORDANCE WITHALL C. STEELSHEET PILES SHALLBE ASTT A572. GR. 50 OR BETTER APPLICABLE STATEAND LOCALREGULATIONS.CONTRACTOR TO SUBMITWELLINSTALLATION LOGS IN ACCORDANCE WITH 0. SHEET PILES SHALLPENETRATE A MINIMUM OF 10 FEETBEYONDTHE BOTTOMOF EXCAVATION ALL APPUCABLESTATEAND LOCALREGULATIONS. E. EXCAVATION SHALLNOT PROCEEDBELOWTHE LEVELOF EACHRING BEAMUNTILTHE RING BEAMHAS REACHEDDESIGN tQC CONTRACTOR TO VERIFYEXISTING/PROPOSED STRUCTURES AND UTILITIES. NOTIFYTHE ENGINEEROF WELLSMOVED COMPRESSIVE STRENGTH MORETHANS FT F. GENERALEQUIPMENT C, DEWATERING PUMPS FOR THE DEEP WELLSSHALLBE PLC COMPATIBLE FOR AUTOMATIC SHUTDOWN BY SWIS RECEIVER F.l. SURCHARGE LOADS:

TANK F.2. MANITOWOC 2250 CRAWLER CRANE

0. GENERATORS OR SECONDARY POWERSUPPLYIS REQUIREDIN CASE OF PRIMARYPOWERSUPPLY FAILURE. ADDITIONAL G. TIMBER PUMPS SHALLBE AVAILABLE IN CASE OF PUMP FAILUREOR REQUIRED MAINTENANCE. 0.I. CRANEMATSSHALLBE 75% HEM-FIR (NORTH)NO. 1 AND 25% HEM-FIR (NORTH) NO. 2 OR BETTER E. ESTIMATED SPECIFICYIELDFOR THE CEMENTBENTONITE WALLCONTAINED AREA IS 5 MILLION GALLONS G.2. DECK OVERLAY SHALLBE HEMLOCK NO. 2 OR BETTER THE GWTSHAS A MAXIMUM CAPACITY OF 300 GPM FOR THE ENTIRESITE WHICHMAYINCLUDEOTHERDEWATERING G.3. GUARDRAIL CONTINUOUS MEMBERSSHALLBE HEMLOCK NO. 1 WORKNOT INCLUDED IN THESE PLANS H. DO NOT DEMOLISHANY RINGBEAMUNTILBACKFILL HAS BEENPLACEDUP TO THE BOTTOM LEVELOF THERING BEAM A G. DEWATERING SYSTEMDESIGNBASEDON A 160 FEETTHICIKAQUIFERCONTAINED WITHINTHE CEMENTBENTONITE SLURRY 18. INSTRUMENTATION/MONITORING WALLCUTOFF A. INCLINOMETERS SHALLBE INSTALLED PRIOR TO CONSTRUCTION OF THE SLURRYWALL

(( ALL PIPINGSHALLBE MINDIAMETER SHOWN ON PLANS. PIPINGMATERIAL IS THE CONTRACTOR'S OPTION; HOWEVER. THE B. PIEZOMETERS SHALLBE LOCATED AT THE COORDINATES PROVIDED. WITHIN5 FEET. IF LOCATIONS VARYMORETHANS PIPINGWILLNEED TO BE SERVICEABLE THROUGHOUT THE LIFE OF THE PROJECTAND COMPATIBLE WITHTHEDWITS FEET. THE ENGINEER SHALLBE NOTIFIED FOR APPROVAL RECEIVER TANS C. PIEZOMETERS AND INCUNOMETERS SHALLBE READBASE ON THE FOLLOWING SCHEDULE AND THE RESULTSREVIEWED I. PRIOR TO DEWATERING EXCAVATION: IN THE FIELDBY THE CONTRACTOR.IN ADDITION, THE RESULTSSHALLBE TRANSMITTED TO THE ENGINEERAND PG&E 1.1. REFER TO THE INSTRUMENTATION & MONITORING SECT7ON FOR REOUIREMENTS PRIOR TO BEGINNING DEWATERING FOR REVIEW. READINGFREQUENCIES BELOWARE MINIMUMS.HOWEVER, DURINGTHE COURSEOF THE JOB THESE 1.2. CEMENTBENTONITE SLURRYWALLSHALLBE COMPLETED MINIMUM FREQUENCIES MAY BE INCREASED OR DECREASED BY CONCURRENCE OF PG&EAND ENGINEER BASED ON THE 1l.3 PROVIDEBERM. AND SLOPEGROUND AWAYFROMEXCAVATION TO CONTROLSURFACEWATER RESULTSOF PREVIOUSREADINGS 1.4. PROVIDE150 FEET HANDHELDWATERLEVELINDICATOR (DURHAMGEOSLOPE INDICATOR OR SIMILAR)FOR USE D. DURINGINSTALLATION OF SLURRYWALL- 1 PER DAY BY OWNER E. PRIOR TO START OF EXCAVATION DEWATERING - MINOF I PER WEEK iNSTALLA FLOWMETER I1* TO MONITOR THE FLOWRATEENTERINGTHE GWTSRECEIVERTANK F. PIEZOMETERS DURINGEXCAVATION - I PER DAY (7 DAYS PER WEEK)

I. PROVIDEROSSUMSAND CONTENTTESTERFOR USE BY ENGINEER.SAND CONTERT IN DISCHARGE SHALLBE G. INCLINOMETERS DURINGEXCAVATION AND BACKFILL- 2 PER WEEK LIMITEDTO IOPPM H. PIEZOMETERS DURINGBACRFILL - 3 PER WEEK J. PRIOR TO INSTALLATION. SUBMITPROPOSEDPUMP INFORMATION. CASINGAND SCREENSPECIFICATIONS. FLOWMETER I. INSTRUMENTATION SHALLBE PROTECTED FROMDAMAGEBY CONCRETE BARRIERS,MANHOLES. OR OTHERAPPROVED MODELAND FILTERPACK GRADUATION TO ENGINEER FOR ACCEPTANCE METHODS K. GROUNDWATER SHALLBE MAINTAINED A MINIMUM OF 5 FEET BELOWTHE BOTTOMOF EXCAVATON 15 AVATIONAND BACKNFILL CUT SLOPESTO BE OBSERVED ON A DAILYBASIS AND AFTER ANY SIGNIFICANT PRECIPITATION EVENTSFOR SIGNS OF INSTABIUTY B. UTLITYLOCATIONS SHOULDBE VERIFIED PRIOR TO EXCAVATION C. SURFACEDRAINAGE SHOULD BE DIRECTED AWAYFROMDESCENDING SLOPES.

0. VEHICLE AND MATERIAL SURCHARGES SHOULDBE KEPT A MINIMUM OF 5 FEET BACKFROMCREST OF SLOPES

16. SOIL NAILWALL A. MATERIALS AND WORKMANSHIP SHALLBE IN ACCORDANCE WITHACI 318 AND ACI 506 (MOST RECENTADDITIONS)

A(/ PERFORMMINIMUM OF ONE CREEP TEST PER -HWA GEOTECHNICAL ENGINEERING CIRCULAR NO.5-SECTION 8.5.5.

PRE-PRODUCTION SOILNAILLOADTESTSHALLBE PERFORMED IN THE COHESIVE& GRANULAR SOILS.

D. THE SOIL NAILSHAVEBEENDESIGNEDIN ACCORDANCE WITHTHE SLD (SERVICELOADDESIGN)PROCEDURES CONTAINED IN THE FHWA 'MANUALF`OR DESIGNAND CONSTRUCTION MONITORING OF SOIL NAILWALLS, REPORT NO.

FHWA-SA-96-069 PRINT IS ONE HALF INDICATED SCALE L DESIGNED BT PROJECTTITLE PROJECTLOCATION JoB No.

EUREKA, CA AS NPG HUMBOLDT BAY POWER PLANT T2-OOR-009

, 09-14-12 G.TIF. IOOX DRAP'TSUBMITTAL K.E.M. DRAWNBY PROJECTTASN DRAWINGNO.

BGALE OE CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-2

,&i 0 9 -- SI . 9 0Z S UBMIT TAL 95-2 N .P.G DATE AFE,-1 S60 SUBMITTAL MPG KIEWIT ENGINEERING CO. CHECKED I1

- SI BY DRAWING SUBJECT SHEETN02 OF 16

-ill GENERAL NOTES REV. I DATE IBY I DESCRIPTION CNWDImffwrr PLAzA OMAHA, HE 6811211 K.E.M.

PLANT LOCATIONS NO. eS PO DNoUumON O. ONO. DUS WION IUNIT REMOVED 12-5 OECGMSAFETYTRAILER 24-A RMdS 32 RIGGING STORAGE - REMOVED 2 UNIT REAOVED 12-6 ENGINEERING TRAILER 2-B HASKELLSAFETYTRAILER 3 NOT USED 3 UNITNUMBER3 12-7 ENGINEERING TRAILER 24-C FINANCE 34 SHEPHERDSSOURCE 4 HOT SHOP 13 COUNTROOM 24-D NORTHCOAST FABRICATIONS 25 UNIT3 WORKCREWBLDG 5 OFFICES,SHOPS, & WAREHOUSE 13-A FOSSILDECOMMISSIONING TRAILER 24-E RADWASTE 36 HBGS WORKSHOP B ADMINISTRAT10N ANNEX 13-B RAP OFFICETRAILER 24-F WARTSILA OFFICETRAILERB 37 ABOSCONTROLROOM 7 TRAINING/NETWORK BLDG 14 SOID RADWASTE HANDDUNG BLDG 24-H FRONT OFFICE/ENVtRONMENTAL 38 HBGSMB-BLDG/CONTROL 8 SECURITY BLDG 15 LOWLEVELRADWASTE BLDG 24-I PROCUREMENT TRAILER 39 HBGS ENGINEHALL 9 FFD TRAILER TB UOUIDRADWASTE BLDG 24-J DECOM6-WIDEOFFICETRAILER 40 HBGSLV-ROOM BLDG 17ASSEMBLY SAS BLDG 25 OFFICETRAILER 41 HBGS FIREPUMP HOUSE TO-A INITIAL TRAINING AND BADGING 1 UNIT3 ACCESSCONTROL 26 PAINT/SANDBLASTBLDG 42 HBOS TEMPOPERATIONS - REMOVED 1 PRIMARYALARM STATION(PAS) T9 27 HBPP RREPUMPHOUSE - REMOVED 42 WACH'STRAILER- REMOVED 12-1 GENERALENGINEERING TRAILER 20 RADWASTE OFFICETRAILER B 28 MOBILEEMERGENCY POWERPLANTI - REMOVED 44 RUBB TENT 12-2 ELECTRICAL ENGINEERING TRAILER 21 HAZARDOUS WASTESTORAGE 29 MOBILEEMERGENCY POWERPLANT2 - REMOVED 45 FUTUREUSE 12-3 MECHANICAL/PIPING ENGINEERING TRAILER 22 NEWGEN/RP B-WIOE OFFICETRAILER 30 MEPP ISLANDBLDG 12-A CIV1L/STRUCTURAL ENGINEERING TRAILER 23 FUTUREUSE 31RELAY BLDG FOOTPATH I ASn

'112113-LC 2 "N 316 SCAL: - 2 it PRINT IS ONE HALF 2N4ICATED SCALE j

t9-412OF. .O RAFT ,SUBMITAL FT

.;: KV eI, itI N.PG. 0.__AS " NOTED

_yC** AL00U" HUMBOLDT BAY POWER PLANT j TAS*K PROJECT EUREKA. CA 12-008-O09 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. BOXISUBMITTAL N.P.. KIEWIT ENGINEERING CO CHECKEDBTY DATE FDRAWING SUBJECT SWEET NO.

RE. DT T DSRPIN CIKS KIEwrr PLZA O N HIA IEt613 RE 7-15--12 RI WT GENERAL ARRANGEMENT PLAN 3OPFI

SIn USE SCHEDULE UQEND NO. D IIOI AREA 1 CONSTRUCT1ON STAGINGAREA 32.802 2A2A GROIUNDWA*ER TREATMENT SYSTEM 8.120 2Zvx1 II 2B OrTS RECEIVERTANK 383 7

3A WASTEMANAGEMENT FACIUTY 12.000 38 DEBRISTESTINGAREA 5.250 F4f INTERMODAL CONTAINER STOCKPILEAREA 46.988 5 SOILSTOCKPILEAREA 30.850 5 SOILSTOCKPILEAREA 33.750 6A CONTRACTOR OFICE TRAILER 1.440 6B CONTRACTOR OFFICETRAILER 2,700 7 HAGS- OPERATINGPOWERPLANT N/A 8 CAISSONREMOVAL AREA N/A

- BUILDINGS/ STRUCTURESTO REMAIN N/A

- INTERMODEL TRUCKROUTE N/A

- CONSTRUCTIONEQUIPMENT & MATERIALS TRUCKROUTE N/A

- STE WALKWAY PAIH N/A

- HBGS ACCESSROUTE N/A SOIL STOCKPILE AREA NOTEE

1. TRAILERSAFLENEEDTO BE MOVEDFROMAREA SA BY JANUARY1. 2014 FOR STOCKPILE CONSTRUCTTON

2. A PORTiONOP AREA 54 1811RE OPEN FOR TRUCATuRNAROUND PURPOSES SITE USE PLAN S.:C -100 ,.I AA PRINT IS ONE HALF INDICATED SCALE DOLE PROJECT LOCATION JOB NO.

PROJECT PROJE LOCATION DESIGNED BY HM PROOECTTBALYER PLANT EUREKA, CA 12-008-009 N.P.

AS NOTED 00--2 T.

SJ.H 09-05-12 78,-21

.,-

700. DRAFT SUBMITTAL 90ROSUBMITTAL ITEM.P MG OK PROJECTTASK CAISSON REMOVAL FEASIBILITY STUDY DRAWING SUBJECT DRAWINGNO.

12-008-009-4

& 0 6W SUBMIttAL DESCRIPTION CA

. KIEIWIT I

wr.G WPAA ENOINEPRINZ CBN.N COj CNEER SS 06 2 SITE USE PLAN A OF 16 REV. I DATE IBYI

LEGEND STORMDRAIN 1ý/ -- --

rI-PRESSURESEWER SANITARY SEWR FRESH WATER FRE WATER PIPES 14" PG&EOIL UNE UTIUTYTUNNEL HUMBEOLDT BAY UT/LITIES PLAN SCAL - I7w , -

HALF PROJECTLOCATION HUMBOLDT BAY POWER PLANT i EUREKA. CA TASK PROJECT PROJECT TASK CAISSON REMOVAL FEASIBILITY STUDY SUBJECT DRAWING STORM, SEWER, WATER, & OIL UTILITIES PLAN

LEGEIND iT4111111CKRI FrHO OVERMEADPOWER

- u- UNDERGROUND POWER TELECOMMUNICA1IONSCONDUIT FiBEROPTIC 7

BAY HUMBOLDT ccm UTILITIES PLAN SCAL 1 - 00' CA REMOVAL FEASIBILITY STUDY SUBJECT DRAWING ERAWINGCSUBJECT ELECTRIC & TELECOMMUNICATION UTILITIES PLAN

LEGEND I V7HYDRONIILL BOUNDARIES 50- FROM I CENTEROF SLURRYWALLON EITHER SIDE SHEETPILE WALLTO CREATE LEVELGRADEFOR SLURRYWALL EQUIP.WALLDESIGNTO BE COMPLETED BY CONTRACTOR RCA ACCESS TRACERTO ATED BEREQEDREO TROa Y PG&E ki SLURRYI' - 21r WALL PLAN NOTE; FINAL SLURRY& DESANI1NG PLANTLAYOUTTO SSIE: I" - 2 BE DETERMINEDBY SLURRYWALLCONTRACTOR PRINT IS ONE HALF INDICATED SCALE PROJECT LOCATION I I @IDESIGNED BY PROJECT LOCATION JOBNO.

HUMBOLDT BAY POWER PLANTTL DTPROJECTTLE EUREKACA T2-008-009 AS NOTED

&09-4-12

.& Io9-05-21*,..HI I YO 0G 9DRAFT SUBMITTAL 9OX SUBA4ITTAL NPGSJ A t BY PROJECTTASK CAISSON REMOVAL FEASIBILITY STUDY DRAWINGNO.

12-0o0-0os-6 KIE IT nOIERNO I

&~ 0O6-T-2 S.J.H.~ 6OZ SUBMITTAL B.P. SHEETNO.

OMNAHA.ME0101311 SLURRY WALL SITE USE PLAN 6 OF 1D REV.I DATE I By I DESCRIPTION OiEDKWTPAA

CONTROL POINT I IN-m rAWIBA5~l or NO 1NTH N KArllNO 2161197.6 1 59493592 2 11 5949401.B 3 2161185.6 5949455.4 4 2161137.2 5949487.1 5 2161081.5 5949497.6 4 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 AREAS OF AN iCIPATEDCONTAMINATION TO BE REMEDIATED PRIOR TO SLURRY WALLCONSTRUCTION. PROPOSED GEOPROBEINVESTIGATION TO DEUNEATEAPPROXIMATE AREASOF CONTAMINATION IN SEPTEMBER2012 NOTES:

1. SLURRYWALLCONSTRUCTION TO START NEARCPul AND PROGRESSIN A COUNTER CLOCKWIME DIRECTION.FINAL STARTING POINT TO BE COORDINATED PATHPG&E.

2. TIMBERPILES UNDERTIJRBINEBUILDING HAVECUT-OPF ELEVATIONS FROMEL-3.0' TO ELI9.0' ASSUMEDPILE CAP THICKNESS IS 2.0'. LENGTH AND DADTH DIMENSIONS OF PILE CAP WERENOT SHO1 ON THE PROVIDED DESIONPLANS AND HAS BEENASSUMEDTO EXTEND18*

/*.( BEYONDTHELIMITS OP THE PILES REFERTO UNITS 1 & 2 FOUNDATION REMOVAL PLANS FOR PILE FOUNDATION DETAILS ALIGNMENT PLAN SCALE:

1 - 20 PRINT IS ONES HALF INDICATED SCALE I I I PROJEOTLOCATION JOB NO.

HUMBOLDT PROJECT BAY POWER TITLE PLANT I EUREKA, CA 12-0OB--009

,, @Kiewit AS NOTED BT I DESIGBED 09-14-12 100.TF.1 DRAFT SUBMITTAL I[~K1~!~FVU~hKDRAWN W BY N PROJECTTASK DRAWINGNO.

6 59oA SUBMITTAL CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-7 E I N.P.0 KIEWIT ENGINEERINGCO DRAWINGSUBJECT V

REV/.

-D5--12 S.J, DATE BT 6OX SUBMITTAL DESCRIPTION CHR'DI EWiT PLAZA OMAHA. ME "1131;I 06-15-12

,I SLURRY WALL ALIGNMENT PLAN I 0SR"T-"07 OF 16

INSTRUMENFT LOCATIONS 17ýý 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 FINALINSTRUMENT LOCATIONS TO BE DETERMINED IN I FIELDBUTSALL BE WITHIN10' OF THESLURRYWALL A UNLESSAPPR OVED BY THE ENCINEER

2. PIPINGWILLBE BURIED. FINALDEPTH TO BE DETERMINED BY DEWATERING CONTRACTOR & APPROVED BY PG-! CONTRACTOR RESPONSIBLEFOR DEWATERING SYSTEMTO RECEIVERTANK. PGOE RESPONSIBLEFOR DEWATERING. FROMRECEIVERTANKTO DISCHARGE PLAN SCALE:

1-30' PRINT IS ONE HALF INDICATED SCALE PROJE CT TITLE I PROJECTLOCATION JOB NO.

AS NOTE0 HUMBOLDT BAY POWER PLANT EUREKA, CA 12-008-009 PROJECTTASK DRAWING NO.

A AF CAISSON REMOVAL FEASIBILITY STUDY 06-15121

-I.

DATE I BY I

IABOSUBM~ITTAL NA G KIEWIT ENGINEERING CO. CHECKIED BY IHj rfI 1---12 LI DRAWINGSUBJECT INSTRUMENTATION & DEWATERING PLAN SHEETNO.

8 OP SR RW. I DATE I BY I D RIPTION CHICO MUNININT PLAZA OMAHA. WE W131 K.E.M.

IS 1

2.50 SLURRYLINES 2.50 _ LRR IE vl gr Lo I~ WLL~I 04Ix 59CSol~ ~_

rny~

i I I I I I[ I I I I I I

,2 I I I I I I I I I I I I I I I I I I I CEME9139/ISAN ATIYET I I I I I I I I I I 7 00 I I I I I I I T2510BAY CLr

~J~1J~

I I I I Liii I I I I

~Nm U

1KIH H INN 1.'r F CLA, ii.E 1-A , -159.1.

tIK*I H 1 t It I ii I It I fib C

U PANEL 2OR , LPPRSMARY

- SCONDARYPANEL TYP C

~~TiPN "N GOXE1-O DISCONINECT (Th TVP LURRYlW WALL PANEL ELEVATION SCALE - A' SWITCH-,, ~NN C

170C OROUND EXISYTG0O0N0

o0E ASSUMEDWATERLEVEL 2e CASING-"*

FILTERMATERIAL lb- NNI I

SLURRYWALLNOTES:

I. TOPOF UNITF CLAYDEFINEDDY GEOTECHNICAL ROTE PVC ELVTO BY12-0 PERFORATED CONTRACTOR FOR PRELIMINARY

2. PRIMARYPANELSCONSTRUCTED WITHHYDRO-MILL BORINGSPERFORMED DESIGNOF SLURRYWALLTIP ELEVATION

& SECONDARY PANELS IPE (20' SECTIONS) 'U CONSTRUCTED WTH CLAM-SHELL 2 3/4' CASING

3. FINAL SLURRYWALLPANELEXCAVATION SEQUENCE TO BE DETERMINED BY PUMP SLURRYWALLCONTRACTOR AND APPOVEDBY PGOE CEMENT/SIENTONITE INSTRUMENTATION AND DEWATERING NOTES:

GROUT

1. INCUNOMETER CASINGSHALLBE DGSISTANDARD 2.75 INCHCASINGOR APPROVED EOUIVALENT

2. PIEZOMETERS SHALLBE 0GS0HEAVYDUTYVISRATING WIRE PIEZOMETERS OR APPROVEDEQUIVALENT *EL -95.0'+/-

3. CEMENTBENTONITE GROUTBACxnLL MIx DESIGNSHALLBE IN EBT-l00.0" IEL OPBOREHOLE& INCLINOMETERt ACCORDANCE WITHTHE MANUFACTURER'S RECOMMENDATIONS. FOR INCLINOMETER'S HARDAND MEDIUM SOILSMIX DESIGNSHALLBE USED.

4. INCLINOMETER CASINGANCHOR AND GROUTVALVEARERECOMMENDED FOR SECTION I(I> AII~n Cr- O INSTALLATION. REGARDLESS OF INSTALLATIONMETHOD CONTRACTOR IS SCALE - A' REGRONSIBLE FOR SUCCESSFUL INSTALLATION OF INSTRUMENTATION WHICH SHALLBE VERIFTED WITHBASELINE READINGS

5. ONE SET OF GROOVESIN THE INCLINOMETER CASINGSHALLBE PLACED PERPENDICJLARTO THEEXCAVATION SLOPE PRINT IS ONE HALF INDICATED SCALE DESwIGnEDBy PROJECTTITLE PROJECTLOCATION JO0BNO.

NPU6 SCALE AS NO HUMBOLDT BAY POWER PLANT EUREKA, CA 12-008-009

. 09-14-12 G.TA 0ooxDRAFT SUBMITTAL K.EM, DR By PROJECTTASK DRAWINGNO.

90% SUBMITTAL NPG. Sj.hL Z* 09--05--12 S.J.H. CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-9

-715-72 SJH. 10% SUBMITTAL N.P0. KIEWIT ENOINEERING CO. CHECKEDBY DRAWINGSUBJECT REV.I DATE I BY I DESCRIPTION I KIEn PZ O NE E111S11 EM I K.CRKD K

HiI, DATE k TYP ELEVATION & SECTIONS BREETNO.

9 OF 16

STORMWATERPREVENTIONNOTES:

1. INSPECTION,CLEANINGAND MAINTENANCE OF ALL EROSIONCONTROLMEASURES SHALLBE DONEON A REGULARBASIS AND PRIOR TO FAILUREOF ANY EROSIONCONTROL DEVICE.ALL EROSIONAND SEDIMENTCONTROLSSHALLBE INSPECTEDAFTER STORMEVENTSAND ON A 17ýý/

WEEKLYBASIS. ALL EROSIONCONTROLMEASURESSHALLBE PROPERLYMAINTAJNED FOR THE DURATION OF CONSTRUCTION UNTILTHE SITE IS STABIUZED.

2- NO SEDIMENT OR SEDIMENTLADENWATERSHALLBE ALLOWED TO LEAVETHESITE WITHOUT GROUNDWATER TREATMENTSYSTEM BEINGFILTERED SOIL & DEBRISTESTINGAREA

3. IF UNFORESEENSOIL EROSIONOCCURSDURINGCONSTRUCTION. THE CONTRACTOR SHALLTAKE ADDITIONALMEASURESTO REMEDYSUCH CONDITIONS AND PREVENTDAMAGETO ADJACENT MODULECONTAINER STOCKPILEAREA PROPERTIES,BODIESOF WATERAND SEWERSYSTEMS.AS A RESULTOF INCREASED RUNOFF AND/OR SED4MENT DISPLACEMENT.OR SEDIMENTATION. SOILSTOCKPILEAREA - REUSE & IMPORTFOR BACKFILL

4. ANY EXISTiNGCATCHBASINS OR STORMWATER INLETS.SHALLHAVEINLETPROTECTION INSTALLEDFOR THEDURATIONOF CONSTRUCTION SOIL& DEBRISREMOVAL TRUCKROUTE S. STOCKPILESSHALLHAVEMAXIMUM 2:1 SIDE SLOPESAND SHALLBE PROTECTED AND MAINTAINED YEARROUND.STOCKPILESSHALLBE COVEREDWITHPLASTICSHEETINGWHEN CONSTRUCTIONEOUIPMENT& MATERIALS TRUCKROUTE STOCKPILEIS NOT IN USE.

6. STOCKPILESSHALLBE COVERED WITHEROSIONCONTROLBLANKETS HBGSACCESSROUTE

7. IF DUST/DEBRISIS DRUGFROMTHE SITE INTOTHE PUBUC RIGHT-OF-WAYIT SHALL IMMEDIATELYBE SWEPTTO THE SATISFACTION OF THE TOWNSHIP SILTFENCE FIBER ROLLS UMBOLDT BAY

-INSTALLFIBERROLLS INSIDEEXISTFENCE UNE

-SEEDETI

- STABIUZEDCONSTRUCTION ENTRANCETYP SEE DETAIL 9 STORM WATER PREVENTION PLAN PRINT 1S ONE HALF INDICATED PROJECTLOCATION JOB NO.

EUREKA CA 12--1 HUMBOLDT BAY POWER PLANT I PROJECTTASK CAISSON REMOVAL FEASIBILITY STUDY IDRAING NO.

12-008-0OO- 1 DRAWINGSUBJECT SHEET O-.

STORM WATER PREVENTION PLAN M0OF 16

AGGREGATE GREATER 'mm BUTSMALLERTHAN6*

ONC FILTERFABRIC

. EXIS T GROUND

'I'm MATCH 0)

C (gD nvTiON C

II.

1. SLT FENCE SHALLBE CONSTRUCTED IN ACCORDANCE WITHCALIFORNIA STORMWATER OUAUTYASSOCIATION STORMWATER BEST MANAGEMENT PRACTICES

2. SILTFENCE SHALLBE INSTALLEDPARALLELTO EYIST1NG CONTOURSOR CONSTRUCTED LEVELALIGNMENTS

3. CONSTRUCT THELENGTHOF EACH REACHSO THATTHE CHANGEIN BASE ELEVATION ALONGTHE REACHDOES NOT EXCEED1/3 THE HOGHTOF THE UNEAR BARRIER,IN NO CASE SHALLTHE REACHLENGTHEXCEED5G0'

4. THE LAST B' OF FENCE SHALLBE TURNEDUP SLOPE

5. STAKEDIMENSIONS ARE NOMINAL

6. DIMENSIONS MAYVARYTO FIT FIELDCONDITIONS

7. STAKESSHALLBE SPACEDAT 8' MAXIMUM AND SHALLBE POSITIONEDON DOWNSTREAM SIDEOF FENCE FIBER ROLL 8B STAKESTO OVERLAPAND PENCE FABRICTO FOLDAROUNDEACH STAKE RUNOFFWATER ý FIBERROLL ONE FULLTURN.SECUREFABRICTO STAKEWITH4 STAPLES. W/SEDIMENT RUNOFFRATER

9. STAKESSHALLBE DRIVENTIGHTLYTOGETHERTO PREVENTPOTENTAL W/ SEDIMENT FILTEREDWATER FLOW-THROUGH OF SEDIMENTAT JOINT. THE TOPS OF THE STAKESSHALL ILTE ED WATER BE SECUREDWITHWIRE.

10. FOR END STAKE.FENCE FABRICSHALLBE FOLDEDAROUNDTWOSTAKES ONE FULLTURN AND SECUREDHITH4 STAPLES

11. MINIMUM 4 STAPLESPEN STAKE.DIMENSIONS SHOWNARE TYPICAL

12. CROSS BARRIERSSHALLBE A MINIMUM OF 1/3 AND A MAXIMUM OF 1/2 THE HEIGHTOF THE UNEARBARRIER

13. MAINTENANCE OPENINGSSHALLBE CONSTRUCTED IN A MANNER TO ENSURESEDIMENTREMAINSBEHINDTHE SILT FENCE MAX 3/4- WOODSTAKE MAG 3/4- WOODSTARE

14. JOININGSECTIONSSHALLNOT BE PLACEDAT SUMP LOCATIONS 0 4.0' SPA 0 4.0' SPA is. SANDBAGROWSAND LAYERSSHALLBE OFFSETTO EUMINATE GAPS

16. ADD 3-4 BAGS TO CROSSBARRIERON DOWNGRADIENT SIDE OF SILT FENCE AS NEEDEDTO PREVENTBYPASSOF UNDERMINING AND AS ENTRENCHMENT- SLOPED AREA ENTRENCHMENT- FLAT AREA ALLOWABLE BASED ON SITE LIMITSOF DISTURBANCE FIRERROLLNOTES' T. FIBER ROLLINSTALLATION REGUIRES THE PLACEMENT AND SECURESTAKING OF THE ROLLIN A TRENCH, 3-INCH TO 4-INCH DEEP.DUGON CONTOUR

2. ADJACENTROLLS SHALLTIGHTLY ABUT

3. RUNOFFMUSTNOT BE ALLOWED TO RUN UNDEROR AROUNDFIBERROLL PRINT IS ONE HALF INDICATED SCALE PROJECT LOCATION JOBNO.

DT BAY POWER PLANT I EUREKA, CA 12-008-009 PROJECTTANK DRAWING NO.

CAISSON REMOVAL FEA IBILITY STUDY 12-008-009--t DRAWINGSUBBJEOT SHEETNO.

STORM WATER PREVENiTION DETAILS 1i OF 16

SOIL NAIL WALL LEGEND SLEGEND DUSCIRPTION

-* V:I OR SLOPEIN DEGREESFROM ESCAVA1lON TVR.1CAI 17ýý SPOTELEVATION SOIL NAIL WALL PLAN

- -l 20' PRINT IS ONE HALF INDICATED SCALE 4 BY DESIGNED N.P.

SCALE A AS NO70 PROJECTTITLE HUMBOLDT BAY POWER PLANT PROJECTLOCATION EUREKA, CA JOB NO.

72-008-009

, -2,*AsNOA AAU:E

, 09--14--12 G. T.F. 100x,* K.E. K iRAFT -UMTA TASK PROJECT DRAWING NO.

A 09-05-12 SJ.H. 90, SUBMITTAL N.P.G. CAISSON REMOVAL FEASIBILITY STUDY 12-008-009-12 AF

,

REV.

06-15-72 DATE S.H.

BY 60X SUBMITTAL DESCRIPTION N.P.GKIEWIT ENGINEERING CO CICHOI IKEWrr PLAZA 011AA . NE 601311 HECKEDBY K.El.E E

lu DATE 06-15-12 INVi7A .1 DRAWING SUBJECT SOIL NAIL WALL PLAN SHEETNO.

12 OF 16

N TVP WALL 10SCALE: OF16 2 LDETAIL G-0T NOTE: 10 LEVELSOF 25' LONGSOILNAILS.4' VERTAND HGRIZSPA TYP TOP OF SOILNAILWALL GEOCOM POSIE DRAINSTRIPS TYP SHOTCRETECONSTRUCTION

-w i i' -III "III "II -II FACING ii ii -ii -ii -i , <

'6 IIG iIII III' IIG IIG IIG 'Jim 'Jim G l 11W i GEOCOMPOSITE DRAINSTRIP 1 (PLACE GEOTEXTILEAGAINST II Gil M11 M1 ml Wi lwl Gil Gil Gil mlI mI GROUND)

GEOCOMPOSITE DRAINSTRIP 6" MIN Ii I.,i 11 11, I l11.

I W11G11'11w il G119'11w i i G JM i ' 11w 11w wiiII' JM i JMI 11wiJM1I ED1~E11w-BENDEDAT THEBOTTOMOF SOIL NAIL WALLTO DAIIGHT FOR WATERDRAINAGE 1 14 ý \ BOTTOM OF WALL S-SOIL NAILSI GEOCOMPOSITE DRAINAGE STRIP DETAIL TVP TOE DRAIN SECTION SCAL.*3/8" = 1V-0 scALE3- - 1V PRINT IS ONE HALF INDICATED SCALE PROJECTLOCATION DESIGNEDBY PROJECTLOCATION JOBNO.

EUREKA, CA i 09- f4

- 12 O. TF. OON DRA FT SUBMITTAL K ,E.M

. DRAW N BY SCALEAS ASN SCALE IPS=mO NOTED APROJECTT TET*PROJECT HUMBOLDT BAY POWER TITL NE R PLANT L N PROJECTTASK CAISSON REMOVAL FEASIBILITY STUDY 12-008-009 DRAWINGNO.

12-008-009-13 109-05-12 S.H. I SOX SUBMITTAL N.P.G. .

W06-15-12SNJ.H. BOX SUBMITTAL B.P.G.KIEWIT ENGINEERING CO. CHECKEDBY lM'J DATE AF DRAWINGS UBJECT SHEETNO.

06-15-12 A- SOIL NAIL WALL ELE VATION & DETAILS 13 OF 16 REV. DATE i BY DESCRIPTION CHK'D KIErWITPLAZA OMAHA. NE CHAEC K. M..

-- PROVIDEMIN 2" COVEROVER WELDEDWRE MESH

-SHOTCRETE CONSTRUCTION BEVELEDWASHER FACING II - -,* " P

-34 CEN'[AUIZER0 MAX8 FT OC ANDý--

PROVIDECENTRAZERSWIIN 24F WALERS DRI OLEAT EDGEOF PANEL WHERERE UIRED-TYP SPHERICAL L LAP = 40 BAR _ L NAILHOLE TYP NUT OR DIAMETERS OR 2.00

,0 U TR MINIMUM O NAILHOLE REINFORCING 11RCAL I 2S50. WELDEDWRVEMESA REINFORORNG4.4-W2.9xW2.9 SOI NAIL DETAIL z HTCRETE PANEL CONNECTOR PLATE

. I'-11 131 SC'E SAE NOT I, ALL NAILREINFORCING #12 REBAROR 1 1/2-0 GRADE75 KSI EXISTREINFORCING SHORT CIER CONSTRUC77ON GEOCOMPOSITE DRAIN STRIP EXI1ST REINFORCING FACING SI-ONICE I EXISTVAIL CON CIRCONG OEOCOMPOSFTE DRAINSTRIP CONSTALLCNAIL STABIUZINS BERM 11101NAILLODCL EXCAVA nON To LOA CELL IRSTAIJRAIL FINALWALLFACE REFERENCE ItAK VRUU A THROUGH DRILLHOLE GOOPST RI TI EXCAVATION UNE .J AC.KHYDRAULIC IN STABILIZING BERM- GEOCOMPOUIEDRAINSTRIP FOR SHOTCRETE BURIEDIN BERM(12 MIN EXCAVATION SHALLE /v iiCAION F AVOID TE CESS HITTING NAILS / BEARING AHER EXCAVATING /N' STABILIZING BERM FNLWL AEml 70 WOOD CRIBBING AND STEELBEARING t EXCAVATION OF TEMP STABILIZING BERM FOR sHOTCRETE PLACEMENT NAIL INSTALLATION ITHROUGH TEMP (CON,,ACTOR S OPTION, VERIFICATION TEST SOIL ",IL DET*AL STABILIZING BERM (CONTRACTOR OPTION)

SCALEI/2 0

-- SCALE: I-: " SC 2' '- "

NOTES:

1. BARE BARSMAYBE USEDFOR SACRIFICIAL TEST NAILS

2. PROOF TESTDETAIL IS SAMEEXCEPTLOADCELL IS NOT REQUIRED PRINT IS ONE HALF INDICATED SCALE S0-9---12 Aio,-T2 A 06-15-12 REV. I DATE I

.FJ.

S.J.IH S.J.I BY I 10X AFT SUBMITTAL AOSUBMITTAL B.OX 5159CRTAL DESCRIPTION N..G.

NAG N.PCG KIEWIT IICOK IIM rr PLAZA ENGINEERING CO. 7EHEKEBRY oM-I-UL.HENSl DESIGNEDBY BRAWNDB NP.(

I1DATE K.E, d.

AS NOTED

.T.O ETS LSS Q*

AL '"

0o-15-12 k

AFE HUMBOLDT PROJECT BAY TITLE POWER PLANT PROJECT TASK CAISSON REMOVAL FEASIBILITY STUDY DRAWINGSUBJECT SOIL NAIL WALL DETAILS

.GEET PROJECTLOCATION EUREKA, CA JOBNO.

12-0DB-009 DRAWING NO.

12-008-009-14 NO.

14 OF 16

WEDGEOGHTTO 12.12 TUMBERDEC CONCF 7 OR 1 1/2' S I M ENý7 " * * ~~HP14x73 ."

MANITOWOC 2250

.7.:

5.06 V'ARIES 2.0 MIN

/SLURRY WAL EXISTINGOR EL +.

UP TO 2' ACTIVATED CONCRETE COULDALREADYSE REMOVED DURING SOILNAILTO PREVIOUS ACTIVITY.

DECOMMISSIONING CONTRACTOTOVERIFYINTEGRITYOF CONCRETE TORESISTLATERAL LOADINGFROMDEMOS EOUIPMENTT 10.00' 1"P VATOR ccI 4.47' ...

10.

M 2pR'DECK RrNI"N CONC UFT JOINT.

ý0-EL -34.011 cc CONGRINGBM:

WP14.73GRILLAGE FRAMEWELDEDTO~

ALLOW REMOVAL AS A SINGLE UNIT CONC fFTJOINT EL 4-47.

____ !X X 41

-- AZ-36 1ip FINISHFLOOR cc Ii.

TRFMIFql1ARRA-F I*L -- IRU T FCO 8.01 I OOKSHORING IOKERSTrY fl~

NOTE SHORING TOWERSCANNOTRESIST LATERAL LOADING FROMEQUIPMENTCONTRACTOR IS RESPONSIBLE FOR DESIGNING LATERALRESTRAINTS FOR THEIR PROPOSEDEQUIPMENT.

t2l. EETPILE

ýýEL

{ EL -51.'

SLURRYWALLo TO -172.0P SECTION. LOWER CAISSON DEMO

-CL:1

- lo' STAGEI: UPPER PORTIONOF REACTORBUILDING STRUCTURE REMOVED.INSTALLSHORINGPLATFORMS, POSITIONEXCAVATOR IN CENTEROF CAISSON.DEMO TRSTLIFTOF EXTERIOR WALLSAND EXCAVATESOIL TO 12' MAXEXCAVATION PAST CENTEROF PREVIOUSRINGBEAM PRINT IS ONE HALF INDICATED SCALE DESIGNED BT PROJECTLOCATION JOBNO.

Kiev t A EUREKA CA 72-008-0O9 N.P.( AS NOTED HUMBOLDT PROJECTBAY POWERTITLE P PLANT 09-14-12 G. TF. 1OXODRAFTSUBMITTAL KE.M. RAWN I- A PROJECT TTANK DRAWINGNO.

A 109-05-12, S.J.H. 1 90X SUBMITTAL N.PG. SG,,h sc, *CAISSON REMOVAL IFEASIBILITY STUDY 12-008-009-15 DRAWINGOSUBJECT SHEETNO.

A

&

06A-T5-T2IL.IH.I 106-15-121 S-M I 6OX SUBMITTAL N.R.G. KIEWIT ENGINEERING CO. CHECKEDBY I DEMOLITION EQUI PMENT SUPPORT REV. DATE I BY I DESCRIPTION CHRO KBSWfl PLAZA O*MIAHA.NB SS13 K. KEM. 06-15-12 15 OF 16

-SLURRY WALLTYP EXISTILG EL+2.0';

GRADE 1111 SOIL

'III RING BEAM

SUMMARY

ID)

ELEVATION CINCiRETE ALT.NAPIr Vc.... W EBE*

(

______

3T) iEAM (IN)

IE SE BEIAN sizE

(.y) (KIPp) C

-34.0 39 W36.232 98.3 58.3

-46.5 44 W36.302 125.1 75.9 CONIC EIT J04INT4 EL -W."*;

4 -59.0 43 W36.302 119.5 75.9 LEVELS -71.5 38 W36x194 93.3 436.3 48.8 258.9 C

III

-33.0 34 W36B170 74.7 42.7 CONEC uFT JOINTo

- 43.0 44 W36 .247 125.1 62.1 EL -47.0' III.

5 LEVELS

,-53.0

-83.0 44 44 W36 W36 .247

.247 125.1 125.1 62.1 62.1 C

-73.0 34 W ,36.170 74.7 42.7 TOTAL 524.9 271.7 FINURP622 NOTE: 61o

1. CONCRETE RING BEAMSHAVEBEEN OESIGNEOAS CAST TREMIESLAB BASE IN-PLACE CONCRETE. CONTRACTOR TO DEVGNREINFORCING STEELANY CONNECTONDETAIL TO SHEETPILE WALL EL OF4,0DoN BOT OF EXCAVARI Np

/(. 28 SAY COMPRESSIVE STRENGTH IS REQUIRED BEFORE EL -80."1 PROCEEDING WITHEXCAVATION UNLESSAPPROVEDBY ENGINEER mm' SECTION - CAISSON DEMO COMPLETE EL-V' III

I" - 10 SCAW t 0.

PRINT IS ONE HALF INDICATED SCALE LTNO.

HUMBOLDT BAY POWER PLANT PROJECTTASK CAISSON REMOVAL FEASIBILITY STUDY BRAWINGNO.

12-008-009-DRAWINGSUBJECT SHEET NO.

SHEET PILE & RING BEAM i's OF .6

HUMBOLDT BAY POWER PLANT EUREKA, CALIFORNIA JOB NUMBER: 12-008-008 UNITS 1 & 2 FOUNDATION REMOVAL FOUNDAflONREMOVALAREA Ai t VICINITY MAP PROJECT SITE SCALE-Nfl SCA.: NTS.

FEASIBILITY STUDY PREPARED BY:

@ Kiewit DISCLAIMER:

"HNE INFORIATION CONTAINED HEREIN I1 INTENDED AS A "PROOF OF CONCEPT AND IS GENERAL IN NATUREr. IT SALL NOT 0 0CO4ST1IRUEDAU CONTAINING ALL NECES*ANY INFORIMATION NE.QUINE1DTO PEWORNiINS T RIL CONTYRWIN KIEWIT ENGINEERING CO. SNALL WE RESPONSIBLE FO1t INDEENNENTLY VALIDATING ALL ELEWENTS tO DESIGN AND PROVIDING ALL REGMUIREDENGINEERING N!ECWSANY TO SUIT ITS KIEWnT PLAZA OMAHA. NE 66131 OWN MEANIS AND MERTHODIS FOR EXECUTING THIE WO"IL

SENERA NOTE&S

1. ALL DIMENSIONS AND ELEVATIONS ARE IN DECIMAL FEET UNLESSNOTEDOTHERWISE ABV ABOVE GALV GALVANIZED DETAIL INDICATOR 2- CONTRACTOR IS RESPONSIBLE FOR OBTAININGALL REQUIRED PERMITSASSOCIATED WITH ADJ ADJJST/ADJUSTABLE GOvT GOVERNMENT HGRND GROUND THE WORK ALT ALTERNATE / - SECTIONOR DETAIL

3. BASE TOPOGRAPHIC. SITE. AND UTILITYPLANS AEREPROVIDED BY PG&E. NORTHING SHEET0 FROM ALUM ALUMINUM NCR HORIZONTAL CONTROLLINE AND EASTING COORDINATES ARE BASEDON NADO3.ELEVATIONS SHOWNAREBASED ON ANCH ANCHOR/ANCHORAGE HORIZ HORIZONTAL WMICH SECTION EEL.- SHEET I -NERE NAVD88. APPROX APPROXIMATELY ID INSIDEDIAMETER OR DETAILIS CUT-.iJ SECT FN OR DETAIL

. COMPACTION OF SAND FILL SHALLBE PERFORMED USINGA VIBRATORY DRUMROLLER 0 AT !E INVERTELEVATION CAN BE FOUND S. COMPACTION OF CLAYFILL SHALLBE PERFORMED USINGA SHEEPS FOOTROLLER AVG AVERAGE INV INVERT B. EXCAVATION AND BACKFILLTO BE PERFORMED IN ACCORDANCE WITHCONTRACT BEL BELOW JST JOIST SPECIFICATIONS.EXCAVATED SOIL SHALLBE CHARACTERIZED IN ACCORDANCE WITH JT JOINT BLDG BUILDING THE NRC/DTSC APPROVEDREMOVAL ACTIONWORKPLANFOR EXCAVATED SOILAND EBK BLOCK K KIP = 10i 0 LBS FOR ON-SITE RE-USE AS BACKFILL B REAM SI KOI KIPS PER OSQUAREINCH

7. TIMBERPILE AND FOUNDATION LOCATIONS.SECTIORSAND DETAILSARE BASED ON: BOC BOTTOMOF CONCRETE L ANGLE SHEET INDEX TIMBERPILE PLACEMENT- SHEET #418767 REV1. 417101 REV3. SHEET 417102-3 SOT BOTTOM

PLUS OR MINUS NO. DRAWINO SUBJECT REV 3 AND SHEET417103 REV 2 BOW BOTTOMOF WALL LBS POUNDS

8. FOUNDATION LOCATIONS FOR UNITS 1 AND 2 TO BE FIELDVERIFIED LU LONG Bp BASE PLATE/BEGIN POINT N. VOIDSLEFTAFTERPILE EXTRACTION SHALLBE FILLEDWITHMINIMUM 50 PSI CLSM LLH LONGLEGHORIZONTAL 1 C1ENERAL NOTES MC BEARING CONCRETE . BRKT LLV LONGLEGVERTICAL BRACKET MAO MAXIMUM 2 SENERALARRANGEMENT PLAN BTWN BETWEEN BVCE BEGINVERTCURVEELEV MECH MECHANICAL 3 SITE USE PLAN BVCS BEGINVERTCURVESTATION MFR MANUFACTURER STORM.SEWERWATER,& OIL UTIUTIESPLAN BW BOTH WAYS MIN MINIMUM AN*

L4J n*Pl TII'n~IIIrlnMi~lrT1HCIA CC CENTERTO CENTER MISC MISCELLANEOUS ELECTRIC & TELECOMMUNICATION UTIHMrS PI Al CARS CAISSON NO. NUMBER FOUNDATION REMOVAL IIf CAP CAPACITY NTS NOT TO SCALE S FOUNDATION REMOVAL PLAN & SECTION OC ON CENTER (i CENTERUNE OD OUTSIDEDIAMETER OF CUBICFEET OPNG OPENING CHAN CHANNEL CJ CONTROLJOINT It PLATE CLG CEIUNG PC PRECAST CUR CLEAR PERP PERPENDICULAR Pi POINT INTERSECTION CLSM CONTROLLED LOW-STRENGTH MATERIAL COG CENTEROF GRAVITY PLF POUNDSPER LINEARFOOT COL COLUMN PLWD PLYWOOD CONC CONCRETE PNL PANEL CONN CONNECTION PSF POUNDSPER SOUAREFOOT CONST CONSTRUCTION PSI POUNDSPER SQUAREINCH CONT CONTINUOUS PM POINT OF VERTINTERSECT CONTR CONTRACTOR R RADIUS CTR CENTER RCSC RESEARCHCOUNCIL ON STRUCTURAL CONNECTIONS CU FT CUBICFOOT REINF REINFORCEMENT CU YD CUBICYARD RECD REQUIRED B DIAMETER REV REVISION ORL DOUBLE OCRED SCHEDULE DEG DEGREE SF SQUAREFOOT SiM SIMILAR DEMO DEMOUSH/DEMOUTION DIRAG DIAGONAL SPA SPACING SPECS SPECIFICATION DN DOWN DWO DRAWING STA STATION STD STANDARD EA EACH SOFF STFFENER EL ELEVATION EMBED ENGR EMBEDMENT ENGINEER STL ST STEEL STREET ft EP ES EQUIP END POINT EQUAL EQUIPMENT SW.

T&B TBD SAFE WORKING TOP AND BOTTOM LOAD TO BE DETERMINED 0.

EVCS END VERTCURVESTATION THK THICK/ THICKNESS EVCE END VERTCURVEELEV TOO TOP OF CONCRETE EW EACH WAY TOF TOP OF FOOTING EXIST E STING TOP TOP OF PIER EXP EXPANSION TOS TOP OF STEEL FF FINISHFLOOR TOW TOP OF WALL FLS FLANGE TYP TYPICAL FND FOUNDATION UNO UNLESSNOTEDOTHERWISE FT FOOT VERT VERTICAL FTG FOOTTNG W/ WITH CA GAUGE W/o WITHOUT WD ROO PRINT IS ONE HALF INDICATED SCALE zj DESIGNEDBY PROJECTTILE HUMBOLDT BAY POWER PLANT PROJECTLOCATION EUREKA, CA JOBNO-12-008-008 N.P.

,* 09-13-12 0. Cr TO.t DRAFT SUBMITTAL KEt BDRAWN BY PROJECTTASK I DRAWING NO.

A, 09- -2 S.J.H. 9 OX SUBMITTAL SPJ UNITS I & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-oo0-oo08-R 6- 5-D2AT.E.H. HOt SUBRIPTAL N.P. KIEWIT ENGINEERING CO. OBECKEDO . DRAWING SUBJECT RSEET NO.

R D.ATE IBY DESCRIPTION EKE'S KIEfWE PLAZA OMRAN,%NE 501311 K E. GENERAL NOTES +/- OF 5

PLANT LOCATIONS NO. DEUCPTO RIO NO. Oluboll" ION NO, UCIMMO I ON NO. DUCRPTI ON I UNIT REMOVED 12-5 DECOMSAFETYTRAILER 24-A RMS 32 RIGGING STORAGE - REMOVEDS 2 UNIT REMOVED 12-6 ENGINEERING TRAILER 24-B HASKELLSAFETYTRAILER 33 NOT USED 3 UNIT NUMBER 3 12-7 ENGINEERING TRAILER 24-C FINANCE 34 SHEPHERDS SOURCE 4 HOT SHOP 13 COUNTROOM 24-D NORTHCOASTFABRICATONS 35 UNIT 3 WORK CREW BLDG S OFFICES.SHOPS.& WAREHOUSE 13-A FOSSILDECOMMISSIONING TRAILER 24-E RADWASTE 36 HBGSWORKSHOP 6 ADMINISTRATION ANNEX 13-8 RVP OFFICETRAILER 24-F WARTSILA OFFICETRAILER B 37 HBGS CONTROL ROOM 7 TRAINING/NETWORK BLDG 14 SOUDRADWASTE HANDLING BLDG 24-H FRONTOFFiCE/ENVIRONMENTAL 38 HBGSMB-BLDG/CONTROL a SECURITYBLDG 15 LOWLEVELRADWASTE BLDG 24-I PROCUREMENT TRAILER 39 HRGSENGINEHALL 9 FS TRAILER

- 16 ULUIDRADWASTE BLDG 24-J DECOM 6-MDE OFFICETRAILER 40 HBGSLV-ROOM 10 ASSEMBLYBLDG 17 RP INSTRUMENTATION BLDG 25 OFFICETRAILER 41 HBGS FIREPUMPHOUSE 10-A INITIALTRAINING AND BADGING 16 UNIT3 ACCESSCONTROL 26 PAINT/SANDBLAST BLDG 42 HBGSTEMP OPERATIONS - REMOVED 11 PRIMARYALARM STATION(PAS) 19 27 HBPP FIREPUMP HOUSE - REMOVED WACH'STRAILER - REMOVED 12-1 GENERAL ENGINEERING TRAILER 2D RADWASTE OFFICETRAILER B 26 MOBILEEMERGENCY POWERPLANT1 - REMOVED 44 RUBS TERT 12- ELECTRICAL ENGINEERING TRAILER 21 HAZARDOUS WASTESTORAGE 21 MOBILEEMERGENCY POWERPLANT2 - REMOVED 45 FUTUREUSE 12-3 MECHANICAL/PIPING ENGINEERING TRAILER 22 NEWGEN/RPS-WIDEOFFICETRAILER 30 MEPP ISLAN BLDG 12-4 CISIL/STRUCIURAL ENGINEERING TRAILER 23 FUTUREUSE 31 RELAYBLDG

' ~CONTRACTOR FOOTPATH /-

2 C:3 2C 12 12--

Is PRIN A FI DI A E C QN PRINT15 OE HAL INDCATEDSCAL N AK IN 2""U RJC TS RWN O UMTALDANB IOOX~~~~~~O 8RF 09-IJ-12~~GEN RA ARRAN EMEN PLAN~rSUM~A ROET KDRWN O

~~

REV.

BADSRPIO ~ ~ ~ ~ ~

H'D[KjwfnWRAA = AZ*

DAE O okJgJNEn r11 ,EM. 6GNRLARNEETPA 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 NIIEWIT ENGINEERING CO. CHECKED BTY DABTE ~ FE Y DRAWINGSUBJECTSETNO REV.J DATE NT DESCRIPTION CR60 MKIEITPLAZA 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 WORKAREA 1,792 2A GROUNDWATER TREATMIENT SYSTEM 8,120 2B GWITSRECEIVERTANK 383 3A WASTEMANAGEMENT FACILITY 12.000 38 DEBRISTESTINGAREA 5.250 4A INTERMODEL CONTAINER STOCKPLEAREA 26.286 (NTEIN ODELCONTAINER STOCKPILEAREA 8.379 SOILSTOCKPILEAREA 30.80 SOILSTOCKPILEAREA 33.751 SA CONTRACTOR OFFICETRAILER 1,440 8B CONTRACTOR OFFICETRAILER 2.700 LI 7 HBGS- OPERATINGPOWERPLANT N/A

[8 B CAISSONREMOVAL AREA N/A

- BUILDINGS/ STRUCTURESTO REMAIN N/A

- INTERMODEL TRUCKROUTE N/A

- CONSTRUCTIONEQUPMENT& MATERIALS TRUCKROUTE N/A

- ITE WALKWAY PATH N/A HBGSACCESSROUTE N/A

- CONSTRUCTION ENTRANCE N/A SOILSTOCAIPILE AREA NOTESi INS I. TRAILERSBILL REEDTO BE MOVEDFROMAREA SA BY JANUART1. 2014 FOR STOCKPILE CONSTRUC TION

2. A PORTiONOP AREA 5A BILL BE OPENFOR TRUCKTURNAROUND PURPOSES cc PRINT IS ONE HALF INDICATED SCALE AS NOTED HUMBOLDT BAY POWER PLANT EUREKA. CA 12-008-"O8 SCALE F -ST 1 tS

.- = ttPROJECT TITLE. PROJECTTASK PROJECTLOGAT)ON JOBNO. NO.

DRAWING

-T -so UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-008-008-3 ATE DRAWINGSUBJECT SHEETNO.

4*jKEWrr ENGINEERING CR8.0; KINAW PtfffA NE CO.

OHWAINA. M131 ICHECKEDBYT K RAI 06-1J-72 SITE USE PLAN 3 OF S

LEGEND

STORMDRAIN PRESSURE SEWER

-- - a SANITARYSE R FRESH WATER

-FIRE WATER PIPES 14" PG&E COLUNE

... UTIUTYTUNNEL 9

IN.

IRN C

C uN INN C

BNI Iii UTILmIES PLAN SCALE:

1, . ,*

PRINT IS ONE HALF INDICATED SCALE SCALE PROJECTTITLE PROJECTLOCATION JOBNO.

rTA-L K7- tN.P.C AS NOTED HUMBOLDT BAY POWER PLANT EUREKA. CA 12-008-008 IOOX DRAFT SUBMITTAL DRAWNBY IT'I PROJECTTASK DRAWING NO.

90. SUBITAL 1.J1- - -T UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-008-008-4A iREV. I DATE I BY I 0 2 SUBMITTAL 60X DESCRIPTION KIEEWIT ENGINEERING CO.

CHWD MKWrr PLAZA OMAHA. MEW131 CHECKEDBY K.E.M.

"I'jt DATE STORM, SEWER DRAWING WATER, SUBJECT

& OIL UTILITIES PLAN SHEETR .

OF 5

LEGEND ITEM DESCRIPTION

-* OVERHEADPOWER

-- UNDERGROUND POWER

- TELECOMMUNICATIONSCONDUIT RIBEROPTIC HU.BOLDTBMY JI.7 it ccN U)

V6 sCA : 1, - IBA' PRINT IS ONE 4AJLF INDICATED SCAA PROJECTLOCATION EUREKA, CA 12-008-HUMBOLDT BAY POWER PLANT I JO1 NO.

PROJECTTASK I DRAWING NO.

UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY DRAWINGSUBJECT 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 REQUIREDDURING FOUNDATION DEMOUTION& PILE REMOVAL INN TOP PILE CAPIGROUNDSURFACE EL VARIES ZN cc) a V6

,MAX PILE PP

ýL-r,- TYPICAL PILE & CAP SECTION

>SCALEW/V" - "-o*

FOUNDATION PLAN SCAL I" - 2a PRINT IS ONE HALF INDICATED SCALE I

L DESIGNED BY PROJECTTITLE PROJECT LOCATION IJOBNO.

HUMBOLDT BAY POWER PLANT EUREKA. CA 12-008-008 09-.3-12 G.F. b00DRAFT SUBMI Kiew it 1RANBY AS NOTED PROJECTTASK I DRAWINGNo.

A 09-10-12 S.J.H. 90X SUBMITTAL NP . SJ ,I UNITS 1 & 2 FOUNDATION REMOVAL FEASIBILITY STUDY 12-008-008-5 A, Inx-,-,I R-IM IJ A 106-15-121 SJ.H I REV.I DATE I BY I 6ox SUBMITTAL DESCRIPTION N.P.G. KIEWIT CHK'DIKiETrrPLAZA ENGINEERING CO. CHECKEDRY OMAHA. NE 68131 E.M.

JJU ik O'_- 13-2 I- DRAWINGSUBJECT FOUNDATION REMOVAL PLAN & SECTION SHEETNO, S OP 5

@ 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 Toal

[Grandotal 26 Grnd $8,043

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

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1000 Articipated Award 33 04-Feb-13 20-Mar-13 Standard 5 Day Workweek 1010 Anticipated Notice to Proceed 0 21-Mar-13 1000 Standard 5 Day Workweek 41 Anbpilpatd S4hidc to Prdciled 1020 Mob Office 10 21-Mar-13 03-Apr-13 1010 Standard 5 Day Workweek 1030 SubmirtApprove Schedule 60 04-Apr-13 26-Jun-13 1020 Standard 5 Day Workweek SrbeIpraveScbeidile; 1050 SubmitlApprove Camson De-o Plan 60 04-Apr-13 26-Jun-13 1020 Standard 5 Day Workweek Subr/Appra ve C Pla .em..o. .

1060 Submit/Approve Sheet Piles 60 04-Apr-13 26-Jun- 13 1020 Standard 5 Day Workweek t= tbirrVApre $tenta f lrlps 1070 1860 Submit/Approve Excavation/Backdll Subirdt/Approve InstruerentaboclEnginneering 60 04-Apr-13 60 04-Apr-13 26-Jun-13 26-Jun-13 1020 1020 Standard 5 Day Workweek Standard 5 Day Workweek

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1040 Submit/Approve Slurry Wall 60 23-May-13 14-Aug-13 1020 Standard 5 Day Workweek Surr~tA0pir& e Sta.rryWall PGEUtlty-co Reov 03r14. P136 Ullity Deconp"bov 1165 Remnove Equip fiom Hot Shop 40 04-Feb-13 29-Mar-13 Standard 5 Day Workweek 1295 BackfillTurbine BldgStructures 11 01-Mar-13* 15-Mar-13 Standard 5 Day Workweek ji Eaýk!l Tcbloe kBlgStrbuctibrres 1155 Perform Sod RercediaSon 109 01-May-13* 30 Sep-13 Standard 5 Day Workweek 1185 Demo SAS to elo +9/BackW 43 01-May-13* 280Jun 13 Standard 5 Day Workweek 1215 CP-7, CP-6 Remove UG obstruconstsystem 20 03-Jun-13' 28-Jun-13 Standard 5 Day Workweek 0 OP 7, CPOP6eRmodeUG bettrbuoalattrr nFSoothydrd

&" C-, CF-e. cP- Ac*Retrieve UD vtnsuoryesrstrnevroEast ot tor brte eBdg 1225 CP-6, CP-5, CP-4 Reronve UG obstr ucionso 22 01-Jul-13' 30-Juol13 1215 Standard 5 Day Workweek 1245 CP-4, CP-3, CP-2 Remove Slope to Grade&lr 11 01-Aug-13' 15-Aug-13 1225 Standard 5 Day Workweek I CP-4, Op-.3,CP-2. Reeorn Slope to GradelirntallPiles 1255 CP-4, CP-3, CP-2 Remove UG Systems Eas 12 16-Aug-13* 02-Sep-13 1245 Standard 5 Day Workweek 12CP-4. CF-S,:.C2' R6"moheUG Syste"n Badt oRff 1265 CP-2, CP-, CP-11 Remove UG obstructions 65 03-Sep-13' 02-Dec-13 1255 Standard 5 Day Workweek J Hbt.S....IR.nt eStal

. .De 1175 Demo Hot Shop/Rennove Stab 44 01-Oct-13' 29-Nov-13 Standard 5 Day Workweek 1275 CP-11 Reroute 480V Cold & Dark power cab 7 03-Dec-13 11-Dec-13 1265 Standard 5 Day Workweek j oFP Rcea eiri 48D4Ckid 6 Dark trower cables:

1285 CP-11, CP-10 Remove UG obstrauctons/syste 15 12-Dec-13 01 -Jan- 14 1275 Standard 5 Day Workweek Sq CF-11: OP-iF R-reoveLUGokhstrdcbnohsyterTs 1235 Relocate Access Control Trailer 23 02-Jan-14 03-Feb-14 1285 Standard 5 Day Workweek .+

0 Reboc te c e vJ rdro-Tri++~rkr. +.ii SlUrry Wall Cotistruction ý;ý I 1150 Demo Unit2 Slab 32 06-Jun-13 19-Juo-13 1030 Standard 5 Day Workweek P: Deno Unit2 Slab; 1160 Eneentelyhornrpt,! PirPIs184 EABacfl! 5 17Jvn-13 02-Sep-13 1150 Standard 5 Day Workweek 1170 InsoaleWells 20 27-Jun-13 24-Jul-13 1860 Standard 5 Day Workweek 01, Ihstall llstrantatwn 1180 Install Instrumontation 20 25-Jul-13 21-Aug-13 1170 Standard 5 Day Workweek 1080 Pre-trench 26 27-Nov-13 01-Jan-14 1160,1285 Standard 5 Day Workweek 1090 Guide Wells 10 19-Dec-13 01 Jan 14 1040,1080 Standard 5 Day Workweek q Comde Web!

1890 Spoil Managenont Area Install 40 29-Dec-13 07 Feb-14 1040,1181 a-1 M oSPil Management Area Install:

1100 Mob Slurry Wa# Equapment 5 02-Jan-14 00-Jan-14 1080 Standard 5 Day Workweek I Mob$kirrrryWfEquEprmnei 1110 Set-up/Test Slurry Wal Equapmnent 10 09-Jan-t14 22-Jan-14 1100 Standard 5 Day Workweek o:Sel-aprblthISojrry WaON Erjcqlmrhe 1181 Move Trailers 0 10-Jan 14' Standard 5 Day Workweek *: Move:Tradets :

1120 Install Panels 84 EA B4 07-Feb-14 04-Jun-14 1110.1090.1890 Standard 5 Day Workweek :7P lrwstal!Panel 64PA 1130 Demob Skirry Wall Equrproent 10 05-Jun-14 18-Jun-14 1120 Standard 5 Day Workweek I) De~rabSiurry We Equiprceot 1190 Unwater 60 05-Jun-14 27-Aug-14 1180,1120 Standard 5 Day Workweek F= r

riwvter 1140 Clean-up/Move Out 5 19-Jun-14 25-Jun-14 1130 Standard 5 Day Workweek 1! OlC -opokdHDot Caiso Demoatio 1200 Demo Turbine Bldg Slab 1200 CY 20 07-Juo-15 03-Aug-15 1050,1120,2190 Standard 5 Day Workweek AN Darrro TyrtrrrreBllg $i512k OY 2320 RFB Slab Demo 15 04-Aug-15 24-Aug-15 1200 Standard 5 Day Workweek : :::::: ::: : : : : :: q::-: :. IF RFBStailDe"nl : ::::: :: :: :: : : ::

: : :.:: : :

1210 Excavate 2000 CY 5 25-Aug-15 31-Aug-15 1070. 2320,1140 Standard 5 Day Workweek 11Excavate 2060 Cry 1220 Pul Piles 143 EA 23 01-Sep-15 01-Oct-15 1210 Standard 5 Day Workweek $I P1Pilese143 EA 1230 Badcfill 10 02+Oct+15 15-OCdt15 1220 Standard 5 Day Workweek : BaCkfill :

Actual Work Crircal Remaining Work Vmmmm Sumnmnary Page 1of8 ASK filter: AllActivities Remrining Work

4 Milestone C Oracle Corporatior

ornia High Speed Rail ,ak I Classic Schedule Layout T- 23-Sep-12 08:3C Pnadeeees1 ae1 11111 IJ111 1A 1 8 1240 Install Falework in Center Tower 5 16-Oct-15 22-Ot-15 1230 Standard 5 Day Workweek I: OýaP nrkentelTw' iaoe 1250 Esrst Fly Equip/Bridge In +12 to +6 1 23-Oct-15 23-Oct-15 1240 Standard 5 Day Workweek 1260 Bsrit Excavation +12 to +6 6 26-Oct-15 02-Non-15 1250 Standard 5 Day Workweek 1270 Bsrnt Soil Nails Instal +12 to +6 (LI) 3 03-Nov-15 S5-Non-IS 1260 Standard 5 Day Workweek IBr4Ply Equip)Brng a~4u -12 tot6:

1280 Bsat Demo Concrete +12 to *6 12 06-Nov-15 23-Nov-15 1270 Standard 5 Day Workweek ":u 0,k 6 IA i12:tot06:2 1290 Bsr6t Fly Equip/Bridge DOt+12 to +6 1 24-Nov-15 24-Non-15 1280 St0nd4,d 5 Dey Workweek 1300 Bs6t Fly Equip/Bridge In +6to +2 1 25-Novw15 25-Nov-15 1290 Standard 5 Day Workweek 1310 B6mt Excavabon +6 to +2 6 26-Nov-15 03-0ec-15 1300,1190 Standard 5 Day Workweek 1:tn Eyrdorel84g.1+12 DPly in t 1320 Bs6mSoil Nails Instal +6to +2 3 04-Dec-15 08-Dec-15 1310 Standard 5 Day Workweek 1OB.arrdly:EqaipAt6dgelIko600.S .-

1330 Bs6t Demo Concrete +6 to +2 12 09-Dec-15 24-Dec-15 1320 Standard 5 Day Workweek atr n . .58.E. . .6.0.2.-

1340 Bsmt Fly Equip/Bridge Out +6 to +2 1 25-Dec-15 25-Dec-15 1330 Standard 5 Day Workweek Baal Exca4N4gnp/afid eto4(0 1350 Bsnrt Fly Equip/Bridge In +2 to -2 1 28-Dec-15 28-Dec-15 1340 Standard 5 Day Workweek 1360 BsmntExcavation +2 to -2 (L3) 6 29-Dec-15 05-Jan-16 1350 Standard 5 Day Workweek :0 PrintDeramCo ete.06t.0:2 1370 Bs.t Soil Nails Instal +2 to -2 3 06-Jan-16 08-Jan-16 1360 Standard 5 Day Workweek Psrrjnt0lyEuJ Bi01oD,# 42:1. -

2330 Adjust Center Tower to El -14 4 09-Jan-16 12-Jan-16 1370 a-1 Eot IB lyEripypl~reidg In.200 -

1380 Bs6t Demo Concrete +2 to -2 12 12-Jan-16 28-Jan 16 1370, 2330 Standard 5 Day Workweek I ,0 EocraSt t20, (L3)]

1390 BsrndFly Equip/Bridge DOt+2 to -2 1 28-Jan-16 29-Jan-16 1380 Standard 5oay Workweek I BroroqNplleotal-t2to 2-1400 Bsmt Fly Equip/Bridge In -2 to -6 1 29-Jan-16 01-Feb-16 1390 Standard 5 Day Workweek Bi64l~orn aýConcrete-2to a 1410 Bs"4 Excavation -2 to -6 (-4) 6 01-Feb-16 09-Feb-16 1400 Standard 5 Day Workweek 1420 Bs6t Soil Nails Install -2 to -6 3 09-Feb-16 12-Feb-16 1410 Standard 5 Day Workweek I OlFyEquipe'65dl1 ~20 1430 Bs6rt Demo Concrete -2 to -6 12 12-Feb-16 01-Mar-16 1420 Standard 5 Day Workweek I 9.4 S 5r6Ilndall i -211 a 1440 Bs6d Fly Equip/Bridge Out-2 to -6 I 01-Mar-16 022Mar-16 1430 Standard 5 Day Workweek 1450 B6t. Fly Equip/Bridge In -6 to -10 I 02-Mar-16 03-Mar-16 1440 Standard 5 Day Workweek If3;r,4benrmConcrete i 201. 10 1460 Bs6 t Excavaonr-6 to -10 (-5) 6 03-Mar-16 11 Mar-16 1450 Standard 5 Day Workweek 1470 Bsrrd Soil Nails Instal -6 to 10 3 11-Mar-16 16-Mar-16 1460 Standard 5 Day Workweek 1480 Btnst Demo Concrete -6 to -10 12 16-Mar-16 01-Apr-16 1470 Standard 5 Day Workweek 1490 Bsmt Fly Equip/Bridge Out -6 to -10 1 01-Apr-16 04-Apr-16 1480 Standard 5 Day Workweek

.80 Stl:NailsrIntal B 10to

-I:

1500 Bsmt Fly Equip/Bridgeln -10 to -14 I 04-Apr-16 05-Apr-16 1490 Stand1rd 5 Day Workwnek 1510 Bs6 t Excavation -10 to -14 ([6) 6 05-Apr-16 13-Apr-16 15D0 Standard 5 Day Workweek 1520 Bs6. Soil Nails Instal -10 to -14 3 13-Apr-16 18-Apr-16 1510 Standard 5 Day Workweek 1530 Bs6t Demo Concrete -10 to -14 12 18-Apr-16 04-May-16 1520 Standard 5 Day Workweek i 65Wt moConcr te -1000o 14 1540 Bs6. Fly Equip/Bridge Out -10 to -14 1 04-May-16 05-May-16 1530 Standard 5 Day Workweek 9j80F qrplipfrslnijlgb 'l 0to 14 1550 Bsmt Fly Equip/Bridge In -14 to -19 1 05-May-16 06-May-16 1540 Standard 5 Day Workweek I BWlEioivtknI sn p44 te- n140. 79 1560 Bs6. Excavation -14 to -18n (LT) 6 06-May-16 16-May-16 1550 Standard 5 Day Workweek 1570 Bs6t Soil Nails Instal -14 to -18 3 16-May-16 19-May-16 1560 Standard 5 Day Workweek 1: isrritStirnols nsortal 14 toý19 1580 Bsrnt Demo Concrete -14 to -18 12 19-May-16 06-Jun-16 1570 Standard 5 Day Workweek 2340 AdjustAI Towers to El -30 15 07-Jun-16 21-Jun-16 1580 a-1 *: AdjutAITnwe. t~o:El 30 1590 Bsmt Fly Equip/Bridge Out -14 to -18 1 21-Jun-16 22-Jun-16 2340 Standard 5 Day Workweek 1:6.80 FNyEq'.!p-ýidtklo ot -1400d 10 1600 Bs6t Fly Equip/Bridge In t18 to -22 1 22-Jun-16 23-Jun-16 1590 Standard 5 Day Workweek 8sirt FlyýEqnjp)jk~oe In t1$ttý22 1610 B64t Excavation -18 to -22 (-8) 6 23-Jun-16 01-Jul,-16 1600 Standard 5 Day Workweek 1620 B6.t Soil Nails Instal -18 to -22 3 01-Ju1-16 06 Ju4l16 1610 Standard 5 Day Workweek * ..... 604Soil"gslostall-atqt-22 1630 Bans Dermo Concrete -18 to -22 12 06-Ju1-16 22-Jui-16 1620 Standard 5 Day Workweek 1;-B"n PN~Enqdpffrellge Out006-22 1640 Bs6t Fly Equip/Bridge Ot -18 to -22 1 22-Ju -16 25-Jul-16 1630 Standard 5 Day Workweek

$.H O.4lyEjqnipýBidg40016-4 to-;20 1650 Bsmt Fly Equip/Bridga In -22 to -26 1 25-Ju1-16 26-Ju1-16 1640 Standard 5 Day Workweek 1660 Bsmt Excavation -22 to -26 (L) 6 26-Ju4-16 03-Aug-16 1650 Standard 5 Day Workweek I Biro! SoilNalsInta-22 <~

to0-20 1670 Bs6t Soil Nails Instal -22 to -26 3 03-Aug-16 08-Aug-16 1660 Standard 5 Day Workweek

640.1 Boeii~crk 101M-22t -26 1680 Bs6nt Demo Concrete -22 to -26 12 08-Aug-16 24-Aug 16 1670 Standard 5 Day Workweek Psr De I. eo, . 0 -22:0-2 Critial Remaining Work . Summ0ary Page 2 of 8 TASK fitter; All Activiies Actual Work Remaining Work *

Milestone C Oracle Corporatoi

alilomia High Speed Rail Classic Schedule Layoot 23 Sep-12 08:3C am I a a 15 2017 1 20 11IIJ141I9I I lq 1 IJJI4fF19 1 I1!1114JII4*19111 11 1_4JH.. l1:~ f 14f11"4 I 1690 Bsmt Fly EquOplBridgeOut -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 i 1: ,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 nCdn*srte -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 :Stae Stroke Oot riorfg EquipmentM, 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 Boda-ateal°c*tRgB6a r(L-L1):

1760 Ring Beam at -34 7 14-Nov-16 22-Nov-16 1870 Standard 5 DayWorkweoek C it ea t0 1790 Excavate to -48 (LL2) 11 23-Nov-16 07-Dec-16 1780 Standard 5 Day Workweek 4 Eocivatie . 8 (Lo42.

2350 AdjustOSTowersto-445 5 08-Dec-16 12-Dec-16 1790 a-1 !dsOS Adj Toweirst1-44:5 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 AusA*t*1t6Tomwr 2to 5:

2400 DemoIS/OS Wais2to-44.5 9 10-Jan-17 18-Jan-17 2390 A iiSiOSWallk2to 1 Da" 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 DayWorkweekB00aet 6 L 2410 AdjustOSTowersto-57 5 14-Feb-17 18-Feb-17 1810 a-1 1 Ajuist OS Towersýt0 -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 :Adjist M.i IS Tower 1 to457 2440 Demo IS Wis 1 to-57 10 05-Mar-17 14-Mar-17 2430 a-I [)etrrp.ltOIsprin 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!1enioI*OS Wals2Io:

1820 Ring Beamat-61 7 27-Mar-17 05-Apr-17 2460 Standard 5 Day Workweek i q q iNR Beim at-64 1830 Eo ate to -73 (LL4) 11 05-Apr-17 20-Apr-17 1820 Stwoarad 5 D yVWV.kweek ' Bcavae tol-731(LLO).

5 21-Apr-17 25-Apr-17 1830 a-1i . . . I S*n.e O.owvry 2470 Remove OS Towers 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:. IRernelS:TbW*e2 2520 DemolSIOSWaeis2to -73 9 24-May-17 01-Jun-17 2510 a-1 i . . . Opeo S/0SIPa*

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 Ca,', o r 1935 Remov SpoilManagement Area 20 26-Jan-17 17-Jul-17 1950 0; RemnoveSpoil 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 Standard5 Day Workwee . I Dmo:Rinj 1800 Bacdllllto -61 8 01-Sep-17 13-Sep-17 1940 Standard5SDay 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 :cliq q 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 mo e::b 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

. =__ *w - . _j8 I'-,- 13"1M Standard 5 Day Workweek A Un1l, 13 29 l~1+11[A4nIiii 144'-111'1111 11 11-t111114JlI11 P1~j4-'I111jq1'1 i PI4 14l1-41 I I

2010 Pul Sheets 112 EA 8 18-OcG-17 30-Oct-17 2000 I PonOSen 2020 Badritl and Deme Soil Nails -34 to +12 55 30-Oct-17 15-Jan-18 2010 Standard 5 Day Workweek

-

. -*o=--_iii Ne uLrar LDern *Slb 2000 CY, Standard5 Day Workweek 11 2010 $laid 2040 Excanate 2000 CY 10 25-Dec17 08-Jan-18 Standard 5 Day Workweek 2G50 PonPiles 195 EA 40 08-Jan-18 05-Mar-18 2040 Standard 5 Day Workweek 20600 Badcf 20 05-Mar-18 02-Apr-18 2050 Standard 5 Day Workweek 21170 DeeroblClean 5 02-Av-18 08-Aor-18 2060 2020 1935 Stadar 5 ay orkeek

-

PG EDeo iisir 3010 VWlieGarery equipment removal - Phase 1 175 02-Jan-12A 25-Jun-12A Mi' a-1 I I I I I I I I I I rupirmn,removay Plrpo 1i I I I I I I I I I I I 29-WW~li

ýNoy-IE. PG&EDecomn*Oeoa 3370 LRW BldgEquip/Pipe Removal Phase I I 29-Feb-12A 18-Dec-12A a-1 LR Bld1E*lp/Pipe Rare*oat Phase I 3530 Offgas Tunnel Equip Removal 1 01-Mar-12A 30-Aog-12A a-1 G Eqip Renoxat 1nel 7 3040 ModifyPEG roorninstal RFBAHU 116 01-Mar-12A 25-Jun-12A a-1 amnisfltaRFPBAHU:

3960 Relocate Freline 79 13-Mar-12A 23-Apr-13 i a-1 Relocate:FIrPrte 2590 Reactor Vessel internals Removal 1 26-Mar-12A 15-Nov-12A a-i ctor Vessel loterpalsRprtonal 3070 Perform instrument Air Mods 65 10-Apr-12A 14-Jun-12A a-1 rtAir Molts 3160 Remove lntermnodals/EquOplTrailers Unit 1,2 11 13-Apr-12A 24-Apr-12A a-i appquopr/Trreiers UnW*12:

2530 Obtain NRC Approval of OOC 3rd Exenmption 1 02-May-12A 01Nowl2A a-1 in NRC Approval of 0*tC 3-rd Exemppton Request 3920 Remove unit 3 Intake Lines at New 60KV Yar 58 22-Mayl12A 19Jul-12A a-1 t 3 bIlnke Lioet at Now 60KV Yard Area 3800 Operatons RFBAHU Vent Mods 11 15-Jun-12A 25-Jun-12A a-1 ; A'-OU Vrit Mods 3020 Build Isolation Wall 28 26-Jun-12A 24-Jul-12A a-1 0)6W01 2600 Remove Concrete Blodk 1 02-Ju1-12A 02-Jul-12A a-1 crete Block 2610 Clean-up Heat Exchangers 1 02-Jul-12 A 15-Aug-12A a-1 eat Podrenger.

2800 Supression Chambers (Ring Headers and D( 1 02-Jul-12A 31-Dec-13A a-i :Slpre~slon Chamb"erS IRIng Hoadors and Droncotrner) NorhISouth Cut Wan opening in RDTVauo 1 02-Jul-12A 24-Ju-12A a-i eprrgrrtiDl/psD' .aut 3360 4160 Erect Tent at LFO Site to Support Waste Pkg 57 02-Ju1-12A 28-Ang-12A a Itat:LFO Sdtt SdpPrort aote'P,.

2620 (-24) Elev Remove Components 1 03-Ju1-12 A 31-Juo-12A a-I a-I e.ntonC.,prt aem* SWdntnyard

~rprets i

Guorng Exaavation 3930 FSS New Switchyard During Excavation 92 23-Jul-12 A 22-Oct-12A a-1 Rartnove o Nmporents 2630 (-34) Elev Remove Components 1 01-Aug-12A 30-Aog-12A a-1 Bldg to CoirercloN 3080 Turn Over Bldg to Contractor 1 09-Aag-12A 09-Aug-12A 3180 Turn Oxer Unit 1,2 Area to Contractor 1 09-Aog-12A 09-Aug-12A a-1 Uni 1.2 AeatoCnridrdoi 3190 Unit 1,2 Slab Prep Grading for Drain 25 10-Aog-12A 03-Sep-12A a-1 Sl.b P.repGrading tsr Dram 3120 Turbine Bldg Concrete Scabbing 80 13-Ang-12A 31-Oct-12A a-l ire Bdg Concetle Siabbilng 2640 (-44) Elev Remove Components 1 03-Sep-12A 27-Sep-12A a-1 lEWRamove:Compenprts 3690 Offgas Tunnel Equip Removal North th LRW 32 03-Sep-12A 04-Oct-12A a-i TvenmlEquip Removal North lb LFWr Big 3200 Remove Above Grade Systems for Oly Wate 14 04-Sep-12A 17-Sep-12A a-1 Abd Gla0e Srsteln fr:Oity:Water.

3090 Turbine Bldg Open Air Derno Survey 53 17-Sep-12A 08-Nou-12A a-1 r~ev Rnroye C"As bilipren*

2650 (-54) ELavRemove Components 1 01-Gct-12A 320 .r-12A a-1 rhire Bd Ven Mde 3960 Turbine Bldg Vent Mods 28 01-Non-t2A 28-NOV-12A 2540 Drain Reactor Vessel into SFP and Apply FPxn 1 195Nov 12A 15-Jan-13A a-1 6rpi Reactor \easol irte $OP adApply Friatrie 3540 Remove Item from Stack 1 295Non12A 28PFeb-13A a-1 ! iif, t~l*nttc 3130 Turbine Bldg Demo Phase I el. 12 90 29-Nov-12A 26-Feb*-13A 4140 Operation of GWTS 1092 29-Nov-12A 25-Nov-15A 2660 Shutdown Heat Exchangers Rm (-14) - Rem 1 27-Dec-12A 23-Jan-13A a-1 Sthrtddwn Heat EakEanorslRnr(-d14) Remrrbv aRxmaikng:Cbmponenmts '

4180 Identify Onsde Clean Backdil 58 02-Jan-13A 28-Feb-13A a-I jdpirify'pyesitleaornicnN-00 2550 Remove CRDMs from Bottom Vessel I 16-Jan-13A 19 Mar-13A a-i1 eoeCDsfomBfvr'lse 1 Actual Work 1 Crtrcal Remarning Work .mlll Summary Page4 of80ASK lfter All Activities Remaining Work *

Milestone/ Oracle Corporahor

IDt California High Speed Rail 2750

,dK Nam ZZ _".T La

(-24) Elev Remove Components RPV Relate,

,m 1 24-Jan-13A 25-Mar-13 A Classic Schedule Layout a-i F

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(-34) len Rer 11 2014 114J CymponleoyRPY Relat ebred 2015...

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11 IJIJIA1I1I1,1JI1 I I ,egretRPVlnterrdakni Spekt*=etPbt F 2080 Segment RPV Internals in Spent Fuel Pool 26 04-Feb-13A 11-Mar-13 Standard 5 Day Workweek 2260 LRW BldgEquip/Pipe Removal Phase 2 191 04-Feb-13A 28Oct- 13 Standard 5 Day Workweek lRWMgi E9rdip),i~pe R'etnitealPhabe;2:

3810 Hot Machine Shop Cal Equip Removal 25 04-Feb-13A 28-Feb-13 A a-1 a-1 ,Ifidg *kTunbel Ord*utFI Tlunhel Nolbtit L'RW4Bkdgl 3700 Ofigas Tunnel Grout FINTunnel North to LRV 53 25-Feb-13A 18-Apr-13A 3030 \aMee Galery equipment removal - Phase 2 273 27-Feb-13A 26-Nov-13A a-1 3210 Partial Remove Unit 2 Pad and Timber pile 58 27-Feb-13A 25-Apr-13A a-i 3780 OffigasTunnel Equip Removal So. RFB and 'r 126 27-Feb-13A 02-Jul-13A a-1 B itS',and Ya gaM DchitrnelhEqutpyR*,nloital 3550 Grout Embedded Pipe Inside Stack 1 04-Mar-13A 01-Apr-13A a-1 0 Gyopt Errhe~ddePippIwui~e Olipol 3820 Hot Machine Shop Equipment 25 04-Mar-13A 28-Mar-13A a-I 2730 Cut Control Rod Blades 1 11-Mar-13A 02-May-13 A a-I CutCyntrintodcBtaders 2090 ES to Demob RPV Internals Equip 41 12-Mar-13 07-May-13 2080 Standard 5 Day Workweek ! E8ES I Demo ib RPV eto n,:terriral l Eqi. .. .. ..

2560 Airgap 66 Nozzles Below Vessel 1 20-Mar-13A 18-Jun-13A a-1 1 i"::'rggp, 66 NozzledBelrbwVeus :

2760 (-34) Elev Remove Components RPV Relate 1 26-Mar-13A 22-May-13A a-i M -ý EýleyRermeCmp:

eO ýeners:"t kelate4 3150 Remove Denmn Fiters in Dernin Room 60 01-Apr-13A 30-May-13A a-i 3830 Characterize and Grout HMS Embedded 30 01-Apr,-13A 30-Apr-13A a.- Sheact roe armdGrout HMSntirdedded .

3560 FSS Stack Embedded Pipe to Remain 1 02-Apr-13A 30-Apr-13A a-I ii P5stacik Embedded FretoRrua 3580 Stack Dame to el. 12 1 02-Apr-13A 30-Apr,- 3A a-1 3220 Unit 1,2 Condensate Pump Casings 29 29-Apr-13A 27-May-13A a-1 0 0Jrit i.c 4fleinjlae 'nAny Casings 3590 SAS Bldg Demo to el. 12 1 01-May-13A 05-Jun-13A a-1 .* !qESAS S iecdriemovo*La 12, 12:

P1,1 P"rdoloe. kah)wn :!i!! i 3850 Hot Machine Shop Concrete Scabbing 30 01-May-13A 30-May-13A a-1 W! p i-ttaclvoetSh pbr ecrate Scabhi ing 2570 Remove Decon Facilty 1 08-May-13A 06-Jun-13 A a-1 2670 Decon/Remove Laydown/Cask Wash Down 1 08-May-13A 05-Jun-13 A a-i E DeprlthRemo Laydusen/"0k Wash Down:

2680 DecornRemove New Fuel Storage/Fuel Pool 1 08-May-13A 05-Jun-1 3 A a-1 UDecpnit(Rynpv N"qwFyiqI$tqrjge/Puyl Pool 2690 Decon/Remove Cask Shipping Area 1 08-May-13A 05-Jun-13A a-1 *Dlecpri/Re"n"n Cask Oh rde4Aria:

2100 Remove Decon Faciity 22 08-May-13 06-Jun-13 2090 Standard 5 Day Workweek 2820 Emergency Condenser Removal 1 13-May-13A 10-Jun-13 A a-1 :1 Ernireni**oyCundeiseri 2770 ( 44) Elev Rmovco Compncnis R,*V Relateo 1 23,Muy-13A 23-Jul-1I A a-1 q" ý4A): Ebb?Ran-ood C6hrity itnn RPV Rektull 3230 Unit 1,2 OilyWaste Sumps, Cond Pits, Pipe 59 28-May-13A 25-Jui-13 A a-1 I" ! O OI W Ve: , Cpncl ýt n ! iPpq 3860 Hot Machine Shop Deiposition Survey 11 03-Jun-13 A 13-Jun- 13 A a-1 lii Hothi Macblehpl Dinsputiob Oravy 62 06-Jun-13A 06-Aug-13 A a-1 Demo61'SASB8 g:'t eoI9 3600 Demo SAS Bldg to el 9 2110 Build RV Containment Faciity 43 07-Jun-13 06-Aug-13 2100 Standard 5 Day Workweek 4:Baild RV ContpinerrieeFaculty.

2580 Build RV Containment Faility 1 10-Jun-13 A 06-Aug-13 A a-1 2700 Survey/Apply Fixatives 1 11-Jun-13A 24-Jun-13 A a-i

rvy dgpy Pygirneep 2740 Emergency Condenser*Asbestos Removal 1 11-Jun-13A 09-Jul-13 A a-1 *Elrjnkred CddneA"estos'Psrdoval 2830 Pre-Clean SFP 1 11-Jun-13A 10-Jul-13A a-1 :1 Pie-Cen F 3610 Offgas Tunnel Decontarmination 63 03-Jul-13A 03-Sep-13 A a-I -

I" G.a*Tuenel~ecbrtairmloeton.

3790 Of(gas Tunnel Decontarnination So. RFB and 91 03-Ju -13 A 01-Oct-13A a-1 I I ý GI T.PneDl n: ý

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2840 Build SFP Containment 1 11-Jul-13A 13-Aug-13A a-1 2780 (-54) Elev Remove Components RPV Relate- 1 24-Jul-13A 22-Oct-13A a-1 .... - : -5!"iih'a*t; rinbe Cunt'arl ts R5ii'R a*li"ed 3240 Soil Remediatoen and Backfillunit 2 Removal 29 29-Jul-13A 26-Aug-13 A a-1 U o errwdratlan and:Bgctdllluitr 2 Remvl 2120 Vessel Segmentation 171 07-Aug-13 02-Apr-14 2110 Standard 5 Day Workweek 3620 BackfillSAS Bldg renovalArea 29 07-Aug-13A 04-Sep-13A a-i *BachfilS'ASMg,rbn)6val~ris1. a ..

2850 Drain SFP and Apply Fixative to Liner 1 14-Aug-13A 07-Jan-14 A a-1 2930 CDP Reactor Caisson Removal CCC Deciaio 1 20-Aug-13A 01-Oct-13A a-1 *D eaftorCdsidoh Ramoda ICCCDcid 3870 Hot Machine Shop Pit Casing Demo to el 9 58 01-Oct-13A 27-Nov-13A a-I WNHot Machiinee:SoPdCse Dem :to el 9 3890 Unit 3 IntakelDischarge Line Removal for TB 119 01-Oct-13A 27-Jan-14A Pit31ntatrelD 6hrare!Lmq Reirr0ylkorTtStSabtne U1cM todicor 10kii Actual Work Remaining Work

CrificalRemaining Work

Milestone V Suroonary Page5 of8 7 ASKfiter: All Activities Oracle Corporabo

Calilomia High Speed Rail I Classic Schedule Layout I 23-Sep-12 08:3(

F t141 1 4111 I9IIIII l11 IJ111 11 1,AI I 2710 (+12) Misc Equip and Systems 1 23-Oct-13A 23-Dec-13A a-I = :m(+12) Misc Equipand Si rto : ! : : !::: :!: : : i: :: : :: : : !:::

2790 (-66) Elav Remove Components RPV Relatet 1 23-Oct-13A 19-Feb-14A a-1 (-o 466>Lý Eel Reeh-6 C6riP nerrts: RIPY tated 3460 Active Radwaste Discharge Line Removal 1 29-Oct-13A 26-Dec-13A a-i Acrive Rqdsrit*.si cr Ihi Removal:

lhihu 2270 2940 LRW Concrete Scabbing Low Level Storage Deconta-mination 24 29-Oct-13 28 29-Oct-13A 29-Nov-13 25-Nov-13 A 2260 Standard 5 Day Workweek a-I Lvi Ls aiLv~lStbrbgeD*=b n

-a ~ ii! ,iii iiiiiiiiiii i9 LLEWddg bi Dp .p*.nSus . - -

3270 LLW Bldg Disposion Survey 1 26-No13A 02-Dec-13 A a-1 3840 FSS Hot Machine Shop Removal Area 29 28-Nov-13A 26-Dec-13A a-1 O PI5 'SHotiMae Shop Remnovi*aArea- -

2280 LRW Buiding Disposition Survey 8 02-Dec-13 11-Dec-13 2270 Standard 5 Day Workweek :i BlpdsigbOSuvey' BLRW:Blalrgý :

3280 LLW Storaage Bldg Removal Below Grade I 03-Dec-13A 16-Dec-13A a.-

i PIPU Ilntvakegahg Ftepv*tefioh r ir 4110 Intake Canal Rernediation 182 10-Dec-13A 09-Jun-14A a-1 2290 LRW Building Demolition to +12 24 12-Dec-13 14-Jan-14 2280 Standard 5 Day Workweek *J LRW Eiui~hg DeR6-imt!on to02 ii 2720 Charact./Grout RB embedded pipe/penetratk 1 24-Dec-13A 24-Apr-14A a-1 ip Ch"a:aýa Gt.rGioat:RB*rWobdidýdpipe/penetratiens 2860 TB Drain Tank (TBDT) Floor Drain Pump 1 24-Dec-13A 19-Feb-14A a-1 ,.. ,. Tank M:TB Drgin , ,. (TBDT)

. , ,Floor , DribirlPurmp .. . . . . . .

4250 Refueing Building Concrete Scabbing 183 24-Dec-13A 24-Jun-14A a-1 3380 LRW HVACMods 1 26-Decn13A 22-Jan-14 A a-i

RW t~q CM44 3430 FSS Active Radwaste Discharge Line Remov 1 30-Dec-13A 27-Jan-14A a-i hi mFSSActUne *Yts*-d D Line Rmprrtal:

nhargq 3880 Bacdill HMS RemovalArea 29 30-Dec-13A 27-Jan-14 A a-1 2810 Remove Supression Chamber Liner 1 01-Jan-14A 08-May-14A a-i Rermch'aSupresarn

::tCnsterg *SlradrgCravrbro Uriver oy~aaersuadRFB ::: :rrg :::

1 2870 Remove SFP Bridge Crane 1 08-Jan-14A 14-Jan-14A a-1 :1 Retnmpve OI P Bjlgq tOrjný 2910 Remove SFP Liner 1 S0-Jan-14A 13-May-14A a-1 OPM Remciv6 SFF Liheti 2880 Survey SFP Bridge Crane and ApplyFabures 1 15-Jan-14A 28-Jan- 14 A a-1 :9 Survey BFP 1ridga Crane and ApplyForturmo 3300 High Level Storage Vaul Removal 1 15-Jan-14A 12-Feb-14A a-1 4260 Construct Shlrry WanAround RFB 180 16-Jan-14A 14-Jul-14A Construct Slurry WallAround R:B a-1 3900 Soil Renaedithon and backfil South End 23 28-Jan-14A 19-Feb-14A a-1 3290 FSS HPghLevel Storage Vaul Removal Area 1 13-Feb-14A 13-Mar-14A a-I 3330 Remove Upper Yard Soils 1 Deep 1 13-Feb-14A 13-Mar-14A a-1 3340 Remove Yard Drain Piping 1 13-Feb-14A 13-Mar-14A 10 Rehmbe Yard, DialnPpieg:

2890 Reacd., Equip Drain Tank - FSS and Grout 1 20-Feb-14 A 25-Mar-14A a-1

~ l6,diuiRFacu Tkk iMd . .t. .l. .a 3310 Ba*dll High Level Storage VWulRemovalAre 1 17-Mar-14A 14-Apr-14A a-1 a-i 3320 FSS Upper YardExc'avaton Area 1 17-Mar-14A 27-Mar-14A 1: FSSUvPet Yardltvba~aldnAred 3350 Bakdfil Upper YardArea 1 31-Mar-14A 07-Apr-14A IBackril Uprer.Yardd~re 43 03-Apr-14 02-Jun-14 2128 StandardS5 Day Workwveek in(Iryrne 2130 Asbestos Removal from Pipe/Equipin Drywel RMa~beosr Removal:from Pmpertquir 2920 SFP Shave Concrete WalllFlor 1 14-May-14A 11-Aug-14A a-1 St'PShave)O C lrate WetsFinr; 2140 Reactor Vessel Cavity (Drywel Systems Rem 80 03-Jun-14 22-Sep-14 2130 Standard 5 Day Workweek 01":kastori/asyelCa~tyr (Qrywe0OSylerrms Renqrnval) 4120 Discharge Canal - SP, Reined, Char. Dsch St 275 10-Jun-14A 11-Mar-15A a-1 IPPPP Dwisharge Caýal - SP,Rente,Chat-D"l Str: Ren*

Disposhion Survey ot RFBAfBerScabbing 1 25-Jun-14A 23-Jul-14 A a-i i i ft :,::DlipysS~

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ot

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AýiP RFQAftnr 9 r $casbing e bbn . .

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2950 2300 Cut 480V Cold and Dark Trench at Slurry We 106 01-Jul-i4A 14-Jul-14A Standard 5 Day Workweek S Cqut48qV Cold ind ParI Trench at hSklSl ie 3470 Radwaste Tank Removal I 15-Jul-i4A 11-Sep-14A a-1 : RedWaste Tank ReOriovda 3480 Abandoned Radwaste Line Removal 1 15-Jul-I4A 11-Sep-14A a-1 P~ndudRecive ste Lin Rt incpio A*

3250 Remove UnLi 1 pad and Remainmig Unit 2 Pa 58 15-Jul-14A 10-Sep-14A a-1 *on*1Rw Retrrdim4pal d1 Revanla 1iirlg:Uit 2:Pid 3630 Offgas Tunnel Demolition 59 15-Jul-14A 11-Sep-14A a-1 QC~gasTuInrtetl~emoiirtin a-1 3640 Demo Stack Slab to el. 9 59 15-Jul-14A 11-Sep-14A a-l Deem ..9 .dSl~

.v . e.9 H 3660 North Yard Elect Ductbank Removal 29 15-Jul-14A 12-Aug-14A *NaGth Yard Elect Duttbamk fRetolvai 3670 North Yard Fire Protection Line Removal 29 15-Jul-14A 12-Aug-14A a-1 *NorsiYardlri~e Pio~e-*niqoJe.F~mqvgl a-i 3680 Notth Yard Storm Drain Removal 29 15-Jul-14A 12-Aug14A

.- I 3710 Remove Offgas Tunnel North to LRW Bldg 58 15-JuIl-14A 10-Sep-14A Remove 'Tunnel*t Tr North ti LRW,Bldg a-1 1 Nes DtthlaskY* r lenma°el wdt Ia el. a 3730 New Offgas Vaut Demo/Tunnel to el. 9 59 15-Jul-14A 11-Sep-14A Actual Work Crital Remaining Work *. Summary Page 6 otB ASK ilter AltAchivoes Remainin9 Work *

Milestone i Oracle Corporatior

-alifornia High Speed Rail Classic Schedule Layout 23-Sep-12 08.30 AzfDAtvt an* :rk 201 290O Dispositon Survey of SFP After Shave Concr I 12-Aug-14A 09-Sep-14A : :is Si05:dp SIF After: Shave toncrete:

offSIFey 3520 Plant Exhaust Fan I 12-Aag-14A 1-Sep-14A 3570 FSS Stack &SAS Bldg RemovalArea 1 13-Aag-14A 10-Sep-14A IN Si Stanack & SAS Bdq'Re~ eALiir !

3490 Backt9flAchveRadwaste Discharge Line 1 08-Sep-14A 06-Oct-14A a-1 0 BPac)rlve Rttadlvaltq Oi.rgutag 3170 FSS UL and U2 Site 29 11-Sep-14A 09-Oct-14A 1P FSS Ljardji2:SRk6 3760 North Yard Drainage System Removal 62 l1-Sep14A !1 Nov 14A North Yard Drainage Systemttemon a-1 3400 North Yard Soil Remediation 1 12-Sep-14A S6-Oct-14A :4 North Yardl Sol Remneohaoh a-1 3440 FSS Radwaste Tank Discharge Line Remova 1 15-Sep-14A 13-Oct-14A S FPSSRgdwasia Ta*k Dislcharse Lino Remnoal: I a-1 3450 FSSAbandoned Radwaste Disch Line Remo, 1 15-Sep-14A 13-Oct-14A 3140 Turbine Bldg Demo Phase 2 88 15-Sep-14" 11-Dec-14 Tunbihdk Bl Dloip Ptak ý2 3720 FSS New Offgas VauJt/StaclfSAS RenovalA 29 15-Sep-14A 13-Oct-14A a-1 1* F5S R e gaa Yrbbi°StaýctS Removaltregi e :

3800 Offga Tunnel Demo So. RFB and Yard 88 15-Sep-14A 11-Dec-14A a-1 1Wt~ Trunnel eao So. RF1 and Yard 2150 Remove Asbestos from Drywell at Liner Pene 24 23-Sep-14 24-Oct-14 2140 Standard 5 Day Workweek 3390 FSS North Yard ExcavationArea 1 07-Oct-14A 04-No-14iA a-1 S F$$ Notit 'ard Pcavtin;A*e 3260 Banckll UL and U2 Site 29 13-Oct-14A 10-Nov-14A a-1 P B", dt! Orond2:Ske 2160 Remove DrywaelLiner 110 27Ocd-14 27-Mar-15 2150 Standard 5 Day Workweek ki6denlneDryte; t Liner 3410 BackfillNorth Yard to +12 1 05-Nov-14A 03-Den-14A a-1 3750 FSS North Yard Drainage System Unit 3 29 12-Nov-14A 10-Dec-14A a-1 :E FSS Ndrth YardDralnagei '"temUnt .. .. ..

2170 Remove Activated Concrete 69 19-Jan-15 23-Apr-15 2160 Standard 5 Day Workweek 4040 North Yard Drainage Removal U1,2 58 20-Jan-15A 18-Mar15A a-1 40980 Unit 3 Discharge Line Downstream ofAnchor 92 12-Mar-i5A 11-Juan15A a-1 hmLimi 3 Dasictrargi LineDmrmtrstream ot.4rcInror en Y 4090 Unitl.2 Discharge Lines Dowrntream ofAnch 92 12-Mar-15A 11-Jun-15A a-1 Lnl 2 D'ch&qa*g e*,Lnes DowinstreameimAncar Blocky 4130 Charaderze Survey of Bay Outside Disc Can 29 12-Mar-15A 09-Apr-15A a-1 U0 Charactedze Set*.yot Bay Ostsale Dsc Canal I 2180 Remove Crane 18 24-Apr-15 19-May-15 2170 Standard 5 Day Workweek 2190 Refueing Building Removal to +12 34 20-May-15 SB-Jul-15 2180 Standard 5 Day Workweek RO"m PRqetungBrdinr Rjntovaltai 12q 4070 FSS UL,223 Discharge Lines RemovalArea 29 15-Jun-15A 13-Ju1-15A a-1 :Q PSSRilr3rtisctRarge1inestýnmoy:lr rea:

2200 Remove RFB +12 Stab at Crane Bay 17 07-Jul-15 29-Jul-15 2190 Standard 5 Day Workweek RpneeaR

, . Ceana6ýSlat Bay 4100 BackfillU1,2,3 Discharge Lines RemovalAreu 29 14-Jul-15A 11-Aug-15A .- I U ll L'2,3 Discharge LaresReromaa Lin"Backf aa 2210 SFP Removal 44 30-Jul-15 29-Sep-15 2200 Standard 5 Day Workweek 3970 Unit I Intake Line Removal from intake Strucl 58 12-Aug-15A 08-Oct-15A a-1 Lnied 1 drake6" Rdmovdt horSvIt~ke Stiubira rALi1lSlab 3980 Unit 2 Intake Line Removal from intake Strucl 58 12-Aug-15A 08-Oct-15A a-1 I L:miki b*eak Reimoovalom intake Stiuarei io9 , to LiZ Slob 3990 Unit 3 Intake Line Removal from 601k yrad to 62 12-Aug15A 12-Oct-15A a-1 IM o 3 loriltr (iak y Rermov 1tal.Sami0tkeattu tohAriBlac t 4050 Unit 1 Discharge Line removalAnchor block " 58 12 Aug15A 098Oct-15A a-1 ingI DaariUnitli LriUne rnro"al Ancnr, block Y 4060 Unid2 Discharge Line removalAnchor Block 58 12-Aug-15A 098-Oct-15A L0 Ongn ischergt Lnj mrnrqamoAnphlý3oýk*Y:

3910 OilyWater Separator Removal 58 21-Sep-15A 17-Nov-15A a-1 IM Wae qily Wtdr Pdritr Rdrrlva!l 2220 Perform Soil Remediataon 17 30-Sep-15 22-Oct-15 2210 Standard 5 Day Workweek 13 0ertormnSo - 'I ralron; 4030 FSS U1,2 Discharge LinesRemoval toAncho 29 12-Oat-15A 09-Non-15A a-1 :1 FIS$U 2 D:iZ arge:Linis Rprioialto Anctro~r:

3940 FSS Unit 1,2,3 Intake Line RemovalArea 28 13-Oct-15A 09-Nov-15A a-1

PSS)Reatpr2,3lpk~rjru~sta CalAe 2960 FSS Reactor Concrete Caisson I 21-Oat-15A 19-Jan-16A a-1 2230 Reactor Caisson Concrete Backfill 35 23-Oct-15 10-Dec-15 2220 Standard 5 Day Workweek SReAfbe CarbabnCoctete BAckfin 400 BackfillU1,2,3 ines removal area 28 10-Nov-15A 07-Den-15A a-1 i~i~:: i :::::ii ii.; :::i Rererfome Urekrlo'*n:_.,r_..SF.P.:a.lp.+pm ii

i i 4150 Removal of GWTS 63 26-NoV-15A 27-Jan16A a-1 4210 CDP Developed Areas Restored 92 30-Nov-15A 29-Feb-16A a-1 CDP,DesaloapeddhreasR rsord 2240 Remove RFB +12 Slab 34 11-Dec-15 27-Jan-16 2230 Standard 5 Day Workweek 2250 Spent Fuel Pool Backfill 20 28-Jan-1 24-Feb-16 2240 Standard 5 Day Workweek rnmotew:bitoralosoniC F~lsa 130:etam 2990 Start Demo of Reactor Caisson/SFP Mileston 0 04-Feb16BA 0-1 3000 Remove Debris from SFP Well Demotion 1 04-Feb-16A 07-Mar-16A a-1

/ Actual Work CriticalRemaining Work W 1 Summary Page 7 of 8 TASK filter: All Activities Remaining Work *

Milestone C Oracle Corporatior

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3500 Baddli Radwaste Tank Line RemovalArea 1 04-Feb-16A 07-Mar-16A a Baci ll Rarlate Tanlk Line Rema* ,agbr t 3510 BaddfilAbandoned Radwaste Disch Linere; 1 04-Feb-16A 07-Maw-16A a- I BacdlolAbanadned R0a0wetDindsLiae Aea 3100 Turbine BldgFSS 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 BackfillNorth 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 P*FirraIAnep 2970 FSS Spent Fuel Pool RenmoalArea 59 07-Mar-16A 04-May-16A a- F 5 Spk"ntS ouPao!Rethnl.ra 4170 Remove Tent fom LFO Site 8 07-Mar-16A 14-Mar-16A a-1 ::i Re*tvo Tent nonLFOQite, 4220 RUBBTentFoundationRemrroval 30 07-Mar-16A 05-Apr-16A a-1 i RUPB TentFoundan Renrvel 4240 FSS SFP Rer*ovalArea 59 07-Mar-16A 04-May-16A a-, FSS SFP Ronio"alAte; 59 14-Mar-16A 11-May-16A a-1 .. . lF Sie 4190 FSS LFOSite 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- Ll3BL* rmArea'Bhcflill 4020 Bacdilt South Yard DrainageArea 30 06-Jun-16A 05-Jul-16 A a-1 I U BsBSo*$°uth Yaird:D nr gArgaa L 3420 LRW Bldg Slab Remo-e to 9 1 09-Ang-16A 10-Oct-16A a-1 Loyet m! 0 Site Restoration 113 09-Ang-16A 29-Nov-16 A a-1 :-7 t f7 4230 Actual Work CriticalRemaining 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 No. 100

aeuiw No. 1 No. 40 No. 200 Su.e'iNUMt*r 100 90 111111. Hill I 1 111 111 1 1 80 111V Hill I 1 111 1 1 70 11V Hill II III Hill II 50 Hill II "40 N I Hill 1 11 30 YX : Hill I 20 9 A\1 U111 I 10 0 111111 t oil 100 10 1 0.1 0-01 0.001 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

-HBPP Caisson OKiewit 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 314nLM& No 4140-10 No. 40 No. 2W 100 90 REL I I IN I I I 80 PIT Hill I I I 70 Hill I I 0 60 Hill I I in 50 Hill

0. 40 N lull 30 Itt f M "ýý4 V:N9II 20 10 0

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 Page. William <WDP7Qjge.com>.

Sent: Mtonday, May 21, 2012 1.V8 PM To: ick.Gura Co: Sun, Joseph; Wooddell. Kathlyn; Ferre, Kent S; Abrahamaou Norman; Klimczak, Richard; nha3@eartlttAnel

Subject:

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 @ Humb*et Bay All Based on the attached Table from HBPP ISFSI PAR, here are various risk levels:

Risk Exposure Return Period PGA 10%in SO years 475years t0.%g 30% in 30 years 8S years -0A8g 50% In 50 years 72 years -0.4Sg S% In S years 97 years "-tSi1g 10%CIn Syears 47 years -0.41g 2%in 2 years 98 years -. Sig 5%in 2 years 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 <JIS4*pe-comm>

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 V1column 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

- (*ydU 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

VI HUMBOLDT BAY ISFSI FSAR UPDATE 03 TABLE 2,6-18 EQUAL HAZARD SPECTRA (g) FOR THE FAULT NORMAL COMPONENT FOR SOIL SAFE CONDITIONS.

Y IIn.... .

Period 1 Yr 25 yr 50 yr 100 yr 500 yr 11.0O00 yvI2,000 yr 5,000 yr1 10,000oyr Ssec) n m, - ' .4 J. I I--

I ani nnrA.9 njiql4R In!*2Ihd I fl7gL7 I A'RAQ* I* *qR?4 I d37gR tI 7"R 0.03 0.04 0.3168 0.4175 0.5379 0.8084 0.9032 09829 1.0971 1.1914 03 L_0,10 0,0076 0.5219 0,6801 0.7940 1,1012 1,95W 1.3389 1.4944 1,6229

-v 0.15 0.0088 0,6578 0.8821 1.528 1M 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 (A 'IA.

0.30 0.0094 0.7644 1.1031 1A4322 2.2161 2A778 2,7427 3.0941 3.3236 O0 0.36 0.40 0.0087 0.0082 0,6846 0I6128 0*.734 0.8953 1.3427 1.2384 2,1535 2,0439 2.4478 2.2503 2,6454 2.4775 2.8930 2.086 3.1113 2,8719 0.

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~

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 3D 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 0.50550*o*0 2 0.8 1.07 57

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.

IJ 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 DIMETERIDEPTH OF BORING: _&X01 18 6 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/24112 SAMPLER: Punch Core & SPT DATE COMPLETED: 8/26/12 LOGGED BY: .JPR

-SAMPLE a!

z Z ~ .SOIL DESCRIPTION z. REMARKS z Wz 0 0 ul _ _ _ __5

-0 12 Upper 5' hand augered 17 SSa- 3 001 SILTY SAND, dark gray, medium dense, moist to wet, fine 4

sand, -40% fines 6

2.5 Grades to siltylclayey Ba-002 LEAN CLAY, dark yellowish brown, faint mottling, stiff to very stiff, variable sand content (<20%)

3.0' 10 SSa-22 .003 4 7

10 SILT WITH SAND, dark gray, medium stiff to stiff, moist to wet, low plasticity, fine sand (10-20%), very fine (<1 mm)

Interbeds 0.5 1.5 Grades into SANDY SILT, strong brown to dark gray (mottled), medium stiff, moist to wet, low plasticity, 40%

fine sand 1.0 1.5 27

15 004 '2.5

.SSa- 4 1.0 005 Thin Interbeds (1-2 cm) of SILTY SAND, typ Iron stained 8

e 2.5 Ba-007 SILTY SAND, brown to dark gray (mottled), medium dense, wet, interbedded with SPISM

-20 32 13 POORLY GRADED SAND WITH SILT, dark yellowish 007 brown (10YR 4/4), medium dense to dense, wet, fine sand, 1i9!(

17 19 5-10% fines BOIG O Pg"ume Io BORING LOG Page Number 1 of 9

Consulting Engineer s & Geologists, Inc.

3yu-812 West Wabash, Eurek6, CiA ph. (707) 441-8856-fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-1 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH 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 SAMPLE-

> FW: .

z 0 :3 SOIL DESCRIPTION REMARKS

.J _I 0in tw L W c 0 a~ (a,

.j w!0 Lu ,4 EE,. a.0 9C r LU0 0 00 , .

am '

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 37 -25 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 42 w30 I Same, 20-30% fine sand POORLY GRADED SAND WITH SILT, dark yellowish brown (10YR 4/4), dense, wet, 10% fines, fine sand 47 15 Occasional thin (<2%) layer of coarse sand/fine pebble, otherwise massive 1,4.1 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,

-40 52 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 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 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-I PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: 1 186 Feet BGS DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT DATE STARTED:

DATE COMPLETED:

8/24/12 8/26/12 [Of 1 LOGGED BY: JPB

-- SAMPLE-z -J 0 M SOIL DESCRIPTION -

REMARKS 0 -1 12 aj .2 8 03

__

Iu . U) 8 ~_) _

LC

_ _ _ _ _ _ __j_ __ _ _ _

,45 57.

POORLY GRADED SAND WITH SILT, dark yellowish brown (1OYR 4/4), dense, wet, 10% fines, fine sand 3.0 Very stiff, Iron stained, sandy interbeds 4.0 Interbedded SPISM with stiff to very stiff clay, 4-6" max, iron stained sands

-50 62 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 67 r.55 Interbedded clay/sand (-1" beds)

-60 72 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, sand 77 -65

-SIL'Y-SA**6D, wn(YR 4/3), dense, wet,flne to------

medium sand, 20-30% fines, Interbeds of coarse sand, BORING LOG Page Number 3of 9

(Consulting Engineers & Geologists, Inc.

. ...... 812 West Wa.ba0sh, Eureka, CA -ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-1 PROJ. NUMBER: 012125 ELEVATION: 12feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: /1 86 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/24/12 1/j iL .

SAMPLER: Punch Core & SPT DATE COMPLETED: 8/26/12 LOGGED BY: JPB

- _SAMPLE S-,

E Lu' IL SOIL DESCRIPTION z.8 REMARKS JI-z

a. CL2 )- LL u n _.-. .. uJ.?

U e

-J UJI < CL0Oa LU. 0 V) W 0 U(. M C___._6R__

predominately fine

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

.. - Consulting Engineers & Geologists, Inc.

.. . 812WestWabash, Eureka, CA ph. (707) 441-8855 fax.(707)441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-1 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING:___ /186 Feet BGS DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT DATE STARTED:

DATE COMPLETED:

8/24112 8/26/12 fjI.I7~ A\ Lo LOGGED BY: JPB SAMPLE z

LU w

aL a. C%

U) 0D SOI uj DECRPTO z. REMARKS

~ ~. 0 ac Z

_j W <' ,( a 0 U)

LU ) U) u0 I POORLY GRADED SAND WITH SILT, dark olive brown 102 -90 sa- SM (2.5YR 3/3), massive, dense, wet, fine sand, massive 032 SPI POORLY GRADED SAND WITH SILT, dark olive brown SM (2,5YR 3/3), massive, dense, wet, fine sand, massive 107 -g5 Sand coarsens to fine to medium, massive, dark yellowish brown, grades siltler at 98' Ba-033 100 112 SWI WELL GRADED SAND WITH SILT AND GRAVEL, dark SP Ba-4,034 grayish brown (2.5Y 4/2), dense, wet, -10% fines, fine to coarse sand, well-rounded, 10-15% fine gravels SM SILTY SAND, dark olive brown (2.5Y 3/3), dense, wet, 20-BS-035 30% fines, fine sand 117 t 105 ssa- Fine gravels (5%) between 105' & 106', 15-20% fines 0361 SM SILTY SAND, dark olive brown (2.5Y 3/3), dense, wet, 15-20% fines, massive fine sand, massive an.

- 110 037 122 Grades slitier BORING LOG Page'Number 6 of-

.. . Consulting Engineers & Geologists, Inc.

..... 4/ 812 West Wabash,. Eureka, CA- ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-1 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 Ga-038 POORLY GRADED SAND WITH SILT, dark olive brown (2.5Y 3/3), massive, dense, wet, medium, well-rounded sand, 10% fines 127 115 ,039 Ba- Trace fine gravels and medium to coarse sand from 116'-

'040 116.5' CLAY, light bluish gray, stiff, moist, stiff, intermittent beds

<1" thick

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

-- "

CLAY, light bluish gray, stiff, moist, stiff, intermittent beds Ba-41 ,<1" thick 120 132 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',

-4 042 medium to coarse sand SP/SM, crudely bedded

- 125 137 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' Ba-D43

- 130 142 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 BORING LOG Page Number 6 of 9

Consulting' Engineers & Geologists, Inc.

I812 West Wabash; Eureka, CA ph. (707)441-8855 W.(707)441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-1 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: 1186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/24/12 SAMPLER: Punch Core &SPT DATE COMPLETED: 8/26/12 LOGGED BY: JPB I SAMPLE -

147 }- 135

- 140 152 No recovery Ba-

,045 1451' 157 140 SPI POORLY GRADED SAND WITH SILT, dark bluish gray SM (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)

Ba0 046 162 t 150 167 t 155 BORING LOG Page Number 7 of 9

Consulting Engineers & Geologists, Inc.

j§7 812lWest;Wabash, ,Eureka, CAl ph. (707) 441855 fax. (707)4441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Powe-r Plant KB-I PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: _186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/24/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 8/26112 LOGGED BY: JPB

- SAMPLE z Lu

-L W L DW U.1 REA I"SOIL

,,, z J .- DESCRIPTION Z R U REMARKS Lu~

0.

U- L-j U) U) C U 0*<=

i _ _ _ _ _ __ _ _ _ __

0 0 U) ca _ _ _

POORLY GRADED SAND WITH SILT CL >4.5 CLAY, greenish black (GLEY 2.5/1 10Y), very stiff, moist, rare medium gravels No recovery (easy drilling), loose sand? silt?

see driller note CL CLAY, dark gray, stiff to hard, wet, low plasticity, <5% fine sand BORING LOG Page Number8 of 9

. 'I 'Consulting Engineerrs & Geologists, Inc..-

t**jj~s4J 812 WestWabash, Eureka, C* 4 ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-1 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 ~~ I LOGGED BY: JPB 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 9of 9

Consulting Engineers & Geologists, Inc.

812,West Wabash, Eureka, CA ph. (707)441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-2 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING:.__ 1I86 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 9/15/12 LOGGED BY: JPB .

T

-r r-~.---¶-,-r -

12 to GRAVEL AND SAND (imported fill for working surface)

CLAY, dark yellowish brown to gray (mottled), stiff, moist, 10% sand, low plasticity 17 -t5 3 1.0 3 ,.CLAYEY SAND, light brown, medium dense, moist?, fine 1.25 5 sand, -30% fines 8b- 1.0 001 SILT WITH SAND, dark yellowish brown to brownish gray (mottled), firm, moist?, 25% fine sand, low plasticity 2.0 Bb- 10 002 0.5 22 f1 0 Becomes dark bluish gray 8Sb- 2 1.5 003 Becomes clayeyer, less sand with organic fines 2

2 Laminated beds 2-3 mm with variable sand content 5-25% 2.5 Bb-

,004 1.75 Bb- 0.751

-15 005 LEAN CLAY, very dark greenish gray, moist?, soft to firm, 27 -5% fine sand sb-LEAN CLAY WITH SAND, dark greenish gray, moist, stiff 006 to very stiff, fine laminated (1-2 mm)

LEAN CLAY, dark greenish gray, moist, firm, <5% fine 32 t20 Bb- sand 007 SSb- 6 008 Becomes mottled strong brown to brownish gray, 5-10%

BORING LOG Page Number 1of9

Consulting Engineers & Geologists, Inc.

S812 West Wabash, Eureka, CA-ph.(707)41-8855 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: 9/12112 SAMPLER: Punch Core & SPT DATE COMPLETED: 9/15/12 LOGGED BY: JPB SAMPLE IZ 0:

co c- W zO *=w " SOIL DESCRIPTION REMARKS uj 0 Wu 0 US~

-, WI W 0 ! W-I-0_ CA 0 c.

sand, homogenous SANDY CLAY, strong brown to brownish gray, stiff to very stiff, wet, low plasticity, 20-30% fine sand, homogenous

.25 37 SILTY SAND/SANDY SILT, dark brown to strong brown to browish gray, medium dense to stiff, wet, interbedded layers (0.5"-3')

SP/SM

30 42 POORLY GRADED SAND WITH SILT, dark yellowish brown (IOYR 3/6), dense, wet, fine sand, 15% fines 47 35

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 40 52 I 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 3.5

,.

L L..

BORING LOG Page Numbr

. .

2 of

.

9. . .

- -Consulting Engineers & Geologists, Inc.

42 D 8.12 West Wabash, Eureka, CA. ph. (707)441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-2 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: 186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 9115/12 LOGGED BY: JPB SAMPLEz Z

Z m.j a WSOIL DESCRIPTION W o REMARKS M~ to0: .

57. r45 2" in distinct zones, poor recovery makes difficult to determine full thickness and extent of deposits Bb-Stratified with SM & SP 016 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 %

62 fines, fine sand, stratified with SP in 1-6" beds, gradational t 50 s8b-017 Grades.into SP POORLY GRADED SAND WITH SILT, dark yellowish brown, dense, wet, stratified with SM Bb-018 55 67 CLAY? (based on drilling resistance and mud performance), did not recover in core Bb-LEAN CLAY, very dark bluish gray (GLEY 2 108 4/1), stiff, 019 moist, -5% fine sand Grades to dark bliush brown (iron stained)

'60 SILTY SAND, strong brown, dense, wet, stratified with tink 72 (<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 SSb-020 Interbeds of silt 77 -65 BORING LOG Page Number 3of 9

S..Consulting Engineers & Geologists, Inc.

812 West Wabash, Eureka,.CA - ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant ELEVATION: 12 feet KB-2 PROJ. NUMBER: 012125 DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: 186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 9/15/12 LOGGED BY: JPB

- SAMPLE zW SOIL DESCRIPTION REMARKS a U. M R.

1W 0( U) (O) 0 a 82 t-70 Becomes dark brown (10YR 3/3)

Stratified sand and clay, iron stained at clay/sand contacts 75 Laminated from 76.5' to 77.5' (-1/4 inch In 1/2 inch beds) 87

. .. _.,- --- .

. -- -

.. . .--- ;,-- ..,- . ..- '- .

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

'80 92 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

,--**-I up to- 1.5" L-. ..

POORLY GRADED SAND WITH SILT, dark yellowish 85 brown, dense, wet, 10-15% fines, fine sand, occasional 97 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 BORING LOG Page Number 4 of 9

Consulting Engineers & Geologists, Inc.

~3'§2 "7812'West:Wabash, Eureka, CA ph. (707) 441-8855 fax.x(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: 1186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 9/15/12 LOGGED BY: JPB SAMPLE-z I- C) 'SOIL DESCRIPf1ON z REMARKS z z a 0 U 0

W U) 0)UU~~ _ _ _

102 '0 14 Sand grades to coarser 37 50/

5" Poorly graded sand with silt in shoe 1074 .95 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 8b-026 Grades to very dark grayish brown (2.5Y 3/2) 112 f 100

'Bb-SM SILTY SAND, dark brown, dense, wet, fine to coarse sand, 027 5-10% fines subrounded to rounded gravel, 20-30% fines, (SHOE), (relative position, contacts, and extent unknown)

SWi WELL GRADED SAND WITH SILT AND GRAVEL, very

- 105 dark grayish brown, very dense, wet, 10-15% fines, gravel 117 Bb-028 SPI/M POORLY GRADED SAND WITH SILT, very dark grayish brown, very dense, wet, 10-15% fines, fine sand, Bb-029 occasional gravel 1-3", stratified with variable coarse sand 110 beds (2-4' thick) 122 30 BORING LOG Page NumberS5 of 9

( . Consulting Engineers & Geologists, Inc. 177 t....... 812 WestWabash, Eureka, CA - ph. (707) 441-8855 fax. (707) 441-88 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Pilant KB-2 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: /186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 9/15/12 LOGGED BY: JPB

- SAMPLE

>~01 ~ U 40U SOIL DESCRIPTION z IL UREMARKS I

wu 0 0 W:'0 _u 3I I . C SP4M 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")

Bb- 12A4 030 127 =115.

132 -t 120 SPI$M POORLY GRADED SAND WTH SILT, very dark greenish gray (GLEY 1 56Y 3/1), very dense, wet, fine to medium Bb- 5.61, 031 sand, homogenous, 15% fines 125 137 sP/ 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 142 t 130

- - --

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

-Consulting Engineerrs & Geologists, Inc. 7-S812 West Wabash, Eureka, .C A ph.(707) 441-8855 fax. (707")441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-2 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING:_/ 186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 9/15/12 LOGGED BY: JPB I SAMPLE ji

-Jz LU t 0

~~ ( > C SOIL- DESCRIPTION 0u N REMARKS

=.

L z

< g. oL _z -

-j L3 ul uj Cu 0j 0- W a.0 L3 LU <() WUL 0

135 147 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

- 140 152 Becomes dense

- 145 157 POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 lOB 3/1), very dense, wet, fine to medium Bb-033 subangular to subrounded sand, 15% fines, occasional 10.6 beds of coarse sand (2-6" thick) 162 - 150 03SSb- 0/1 I

034 6, 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

- 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 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-2 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: /1l 86 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/12/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 9/15112

/pf7 LOGGED BY: JPB

-SAMPLE-SOIL DESCRIPTIONREAK

.1 Z a.a CL Wz uj 0 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 ab-038 172 - 160 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 177 K165 POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 10B 3/1), medium dense to dense, wet, fine 3.5 to medium sand, subrounded, 15% fines, rare coarse 3.0 sand, homogenous, crudely bedded with variations in 4.0 Bb-

037 coarse sand 4.5 11.'s 3.75 4.5 182. 170 >4.5

.4.0 b.* 3.5 4.0

>4.5

>4.5 CLAY, very dark gray (GLEY I N 3/), very stiff, moist, >4.5 187 -175 homogenous, low plasticity, occasional to common shall >4.5 fragments (zones)

Bb-039 Homogenous clay 1 .. . BORING LOG Page Number 8 of 9

(*Y Consulting Engineers & Geologists, Inc.

812 West Wabash, Eureka, CA ph. (707) 441-8855 fax. (707) 4414877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-2 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING:_ 1 36 Feet BGS DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB DATE STARTED:

DATE COMPLETED:

9/12/12 9/15/12 DO WAi 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 Thick accumulations of shelly debris Slight variations In slit content within crudely bedded zones 197 Thick accumulations of shelly debris 202 207 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 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant ELEVATION: 12 feet K13-3 PROJ. NUMBER: 012125 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: glhl LOGGED BY: JPB 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 0

12 F : CONCRETE I

AGGREGATE BASE ROCK (up to 3") /

SILTY SANDIPOORLY GRADED SAND (FILL), mixture of silt and sand 17 LEAN CLAY, strong brown, stiff to very stiff, moist, low 1 plasticity, <10% fine sand 22t 0 I

SSc- 2 1.5 001 Grades to bluish gray at 11.5' 3 2.5 4

LEAN CLAY, strong brown, stiff to very stiff, moist, low 2.5 plasticity, <1 0% fine sand go-002 27 -15 SSM- 2 1.25 003 3 1.0 5 1.0 LEAN CLAY WITH SAND, very dadr greenish gray (GLEY Bo-004 2 586 3/1), medium stiff to stiff, moist, low plasticity, 20% fine sand, occasional plant fiber/roots 1.0 32 -20 3.5 1.0 BORING LOG Page Number I of 10

Consulting Engineer s & Geologists, Inc.

812 West Wabash, -Eureka, ClA ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-3 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: /201 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 914112 SAMPLER: Punch Core & SPT DATE COMPLETED: ___

LOGGED BY: JPB SAMPLE i 0 W. 0

.1 SOIL DESCRIPTION z REMARKS U L4J. Z!~ 09_

g Uj w11 0 0I=*

NOa- 8 >4,5

.005 12 >4.5 12 >4.5 SILTY SAND, dark yellowish brown to light gray (mottled),

medium dense, wet, 15-40% fines, fine sand BC-

"25 006 37 Grades sandier with depth with 1" intervals of clayey sand/sandy clay SSc- 10 007 13 10 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' 42 t30 SSc- 17 009 Sand coarsens to fine to medium sand, massive 15 18 Interbedded silty sand/sandy silt with 15% fine gravel SILTY SAND, dark yellowish brown, medium dense, wet, Bc- fine to medium sand, 30% fines, grading sandier with 010 depth 47 Sic- 10 011 11 12

'SILTY GRAVEL SAND, up to 2' gravel, well rounded '

CLAY, 2" layer, bluish gray 52 t-40 SILTY SAND WITH GRAVEL, dark brown (10YR 3/3),

dense, wet, fine to coarse sand, subrounded to well sBc- rounded, 15-20% fine to medium gravel, 15-20% fines 14 013 POORLY GRADED SAND, dark grayish brown (10YR 4/2),

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 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant 1<KB-3 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: 12101 Feet BGS ...

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

LOGGED BY: JPB

- - SAMPLE 0

ZU ~LU~ ~SOIL DESCRIPTION 0~W Z aI Za

_J uj 0, . L 0 9- Io gt0 (0 W 1 10~~1 IJ dense, wet, 5-10% fines, fine sand Coarse sand layer (2')

80- 19.C 014 Grades to

-45 SILTY SAND, dark grayish brown (IOYR 4/2), dense, wet, 57 20-30% fines, massive 6" layer with 10-20% gravel, well rounded, up to 1.5" 8Sc-

-015 SILTY SAND, dark grayish brown (10YR 4/2), dense, wet, 20-30% fines, massive s0-

.016 Assume shoe plugged on gravel lense at 50' 62 -t 50 CLAYEY SAND, light gray, dense, 40% fines (2" in SPT)

SSo-017 WELL GRADED GRAVEL WITH SAND SSc-016 POORLY GRADED SAND WITH SILT, dark yellowish brown (1OYR 4/4), dense, fine sand, -10% fines WELL GRADED GRAVEL WITH SAND, . color??,

0c- dense, wet, medium to coarse gravel (up to 3"), well

. 019 rounded 67

-55 SILTY SAND, dark yellowish brown, medium dense to dense, wet, fine to medium sand, 20% fines

'ClY,V ,dark ibluish :g*, (GLEY 2.5PB'A/1 ), veij stlff,.'moist, 3.5 3.5 lowpqistIblty, -5%~fi~ne sand 4.5 POORLY GRADED SAND.WITHSILT, dirk yellowish brown (110YR 3/4)', medium dense, .wet," e to.medium sand,i-10-15% fines Be- 10.0 021 72 t60 Zones of iron staining SSc-022 Thin lenses of silt/clay (<1/2")

BORING LOG Page Number 3of 10

T 'Consulting Engineers & Geologists, Inc.

812Wqst;Wabash,:Eureka, CA ph.(707)441-8855 fax.(707)441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION: 12 feet K13-3 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 SAMPLE ze -C Z a2 SOIL DESCRIPTION REAK Z LU Z.

0- 0 W c' IL.

CL Brownish gray below 63'

-p65 >4.5 77 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 2.5 1.5 I

3.5

>4.5

'70 Thin laminations of clean sand 82 2,5

>4.5 Very thin <1 mm laminations of silt/clay with sandy intervals, typically 0.25-0.5" in thickness and iron-stained iSM SILTY SAND, dark yellowish brown, dense, wet, fine to medium sand, 15-30% fines, interbeds of clay typically 118-114" thick z75 87 SM SILTY SAND, dark yellowish brown, dense, wet, fine to i 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 92 "80 SM SILTY SAND, dark yellowish brown, very dense, wet, fine to medium sand, 5-10% fine gravel, well rounded to subrounded, fine to coarse sand SP POORLY GRADED SAND, dark yellowish brown (10Y 3/4),

dense, wet, fine sand, -5% fines BORING LOG Page Number 4 of 10

(-..Y7 Consulting Engineers & Geologists, !nc.

....... 812 West Wabash,, Eureka CA ph. (707) "1-8855 hfax (707) 4 41-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Pow er Plant KB-3 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DRILLING METHOD: Mud Rotary DIAMETER/DEPTH OF BORING DATE STARTED: 9/4/12

/201 Feet BGS ..

n)i

.

SAMPLER: Punch Core & SPT DATE COMPLETED:

LOGGED BY: JPB SAMPLE---

zw 0

z 90

> _j _ _ _ _ _ _ _ _ _ _ _ _ a X5 _ _ _ _

sc- : 4.5 030 97 t5 SSc-031 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",

0c- -5% fines 032 Gravel content decreases with depth, fines increase 102 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%

X: .033 fine gravel, up to 1/4" 107 -.95 WELL GRADED SAND WITH SILT AND GRAVEL, very Bc-034 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 112 -,10 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 105,1 BORING LOG Page Number 5of 10

Consulting Engineerrs & Geologists, Inc.

5... 812 West Wabash. Eureka', C.A ph. (707) 441-8855 1Fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-3 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

-SAMPLE 0 0

>, .SOIL DESCRIPTION z 'L4 a REMARKS J .J ),k,

> 0 0 CL CL-. 0 mf 0 .

.j W I, ISLU~~

IOU 23 I

~C.i.~0 LUJ 0 U) Cn .U)0~ 1jX.- :3___

117 T 105 SILTICLAY. very dark grayish green (GLEY 1 56 3/2), stiff, wat .10%Tfnesand'.thin laminations. .......

WELL GRADED SAND WITH SILT AND GRAVEL, very dark greenish gray, dense, wet, fine to coarse sand, 036 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

- 110 3/8"), -10% fines, 15-20% fine gravel, massive 122

Bc-037 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

-115 127 Bc-038 POORLY GRADED SAND, very dark greenish gray, very dense, wet, <5% fines, fine sand Zones of gravel and coarse sand (location and abundance Bc- uncertain due to poor recovery)

,039 SILTY SAND, very dark greenish gray, dense, wet, 20-30%.1 fines, fine to medium sand (SHOE)

BC-040 ,POORLY GRADED SAND, very dark greenish gray, very 120 1dense, wet, <5% fines, fine sand 132 1 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 Bc-

-----

0417 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 125 gray, dense, wet, fine to coarse well-rounded sand and 137 T fine gravel (up to 3/8"), <5% fines BORING LOG Page Number 6 of 10

.*Z9Y7 Consulting Engineeras & Geologists, Inc.

4,7 812 West Wabash, Eureka,',PjA ph. (707) 441-8858 - faxt. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-3 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: I 201 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/4/12 p SAMPLER: Punch Core & SPT DATE COMPLETED: ho!/\A'ý 51;1 LOGGED BY: JPB

-- SAMPLE z

z UU le -

q~ c- SOIL DESCRIPTION Z0 REMARKS U. (9 U:

CL P z

~Z i~~

IL LU W

WLU W

<4.

0 ( LU

>

0 I-E.

I LU g, 0U U) (f), 51 _ __ _

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 Bc-042 130 142 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 Bc-Sand coarsens between 132.5'-135', 5-10% fine gravel 043

-135 i 147 ,!

POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 108 3/1), dense, wet, fine sand, <5% fine gravel Bc-044

- 140 152 POORLY GRADED SAND WITH SILT, very dark bluish

.gray (GLEY 2 108 3/1), dense, wet, fine sand, <5% fine gravel, massive 157 -145 POORLY GRADED SAND WITH SILT, very dark bluish gray (GLEY 2 108 3/1), dense, wet, fine sand, <5% fine BORING LOG Page Number 7ef 10

. 2I Consulting Engineers & Geologists, Inc.

812 West Wabash, Eureka, CA ph. (707)441-855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION: 12 feet KB-3 DRILLER: PC Exploration DRILLING METHOD: Mud Rotary DIAMETERIDEPTH OF BORING:

DATE STARTED: 9/4112 2C31 Feet BGS LW] ZrI,'

!.!

SAMPLER: Punch Core & SPT DATE COMPLETED:

LOGGED BY: JPB 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 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-3 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING:___/ 2C)1 Feet BGS DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT DATE STARTED:

DATE COMPLETED:

9/4/12 LM ~iL LOGGED BY: JPB SAMPLE z

z 0SOIL DESCRIPTION UZ REMARKS

1* . 0= U =W Z ,- _ CD a- ,=

IJ J J LU 0

-;n _ _ _ _

.I-

_ _ _ _ _

r...

1W 170 POORLY GRADED SAND WITH GRAVEL, very dark 182 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 187 -.1751 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 192 t o180 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) 197 t 1851 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 BORING LOG Page Number 9of 10

Consulting Engineers & Geologists, Inc. .

812 West Wabash, Eurpka, CA ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-3 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: /2 01 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 9/4/12 SAMPLER: Punch Core & SPT DATE COMPLETED:

LOGGED BY: JPB I--I SAMPLE *I iz°- 00i, L

- A.

z*

" -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 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: -&-el 186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/20/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 8/30/12 LOGGED BY: JPB 12 T0 1 10" of Imported gravel fill, angular,"washed", dry, filter at 10" Nfabric, non-woven /

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 17

.5. 2 SSd- 1.0 001 5 LEAN CLAY, olive brown (2.5Y 5/3), medium stiff, moist, 1.25 7 low plasticity 1.0 Varies from moderately stiff to stiff, becomes dark gray (2.5Y 4/1) at 7' 2.0 4 S002

.d-Grades silty at 8.5' 0.5 22 ti1 SSd- 3 003 5

8 1.5 SILT, dark greenish gray (106Y 4/1), stiff, moist, low plasticity Thin interbeds of SILT WITH SAND (11cm) 2.5 1.75 Bd-005 0.75

-15 SSd-7 27-8 11 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 32 -20 88d- 8 006 INTERBEDDED SILT AND SILTY SAND, very dark 13 greenish gray (106Y 3/1), medium dense???, moist to wet, 18 fine sand, rare wood fragments, interbeds thicken to 3-4 cm BORING LOG Page Number I of 9

( YConsulting Engineers & Geologists, Inc. BORING LOG "812 W st Wabash, Eure'ka,'CA ph. (707) 441-8855 fia. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: __ 1186 Feet BGS DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT LOGGED BY: JPB DATE STARTED:

DATE COMPLETED:

8/20/12 8/30/12 .n1i3

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'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')

SIL*Y*SAND/POORLY GRADED SAND WITH SILT, dark yellowish brown, dense, wet, fine to medium sand, -20%

52:t40 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' I CLAY, dark gray, stiff to very stiff, moist to wet, thin clay at. \1 3.5 BORING LOG Page Number 2of 9

Consulting Engineers & Geologists, Inc.

. .. 812 West Wabash, Eureka, CA - ph. (707) 441-8855 fax. (707) 441-8877

/I BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: /186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/20112 SAMPLER: Punch Core & SPT DATE COMPLETED: 8/30/12 LOGGED BY: JPB SAMPLE -

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"45 bottom of core run capped with gravelly sand (iron stained) 57 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 62 t 50 Sand coarsens at 50' SILTY SAND, dark yellowish brown (10YR 316), dense, wet, fine to coarse sand, 20% fines, 10% fine gravel, well- 4.0 rounded, gravels with Isolated zones 67 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

-60 yellowish brown, dense, wet, fine to coarse well-rounded 72 sand and gravel, -10% fines, 10-15% gravel

- -- - - _ - ------- -.-

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POORLY GRADED SAND WITH SILT, dark yellowish brown (10YR 3/4), dense, wet, fine to medium sand, 10-15% fines

-65 77

-P-O-O-RL-Y- GRADED SAND WITH SILT, derk yellowish 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 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: /186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/20112 SAMPLER: Punch Core & SPT DATE COMPLETED: 8/30/12 LOGGED BY: JPB

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'.

87 SSd-024 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

, Bd-025 92 t 80 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 97 .85:

POORLY GRADED SAND, dark brown (10YR 3/3), dense, wet, -5%fines, fine to medium sand Bd-027 SILTY SAND, olive brown (2.5Y 4/3), dense, wet, 20-30%

fines, fine to medium sand, rare fine gravel BORING LOG Page-Number4ofg

( U 7Consulting Engineers & Geologists, Inc. _ _

t11j( 82'West:Wabash, Eureka:, CA,, ph. (707) 441-8855 -fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETERIDEPTH OF BORING: 1186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/20/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 8/30/12 LOGGED BY: JPB

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102 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 107 POORLY GRADED SAND, dark brown to olive gray (5Y 4/2), dense, wet, fine sand, -5% fines 112 WELL GRADED SAND WITH SILT, dark grayish brown, dense, wet, fine to coarse sand, sub-rounded to rounded, 15% fines, 10% fine gravel, Interbedded with fine 117 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

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POORLY GRADED SAND, olive brown, dense, wet, fine to medium sand, 5-10% fines 122 CLAY layer (2") iwth a 1.5" chert clast, stiff, low plasticity POORLY GRADED SAND, olive brown, dense, wet, fine to BORING LOG PageNumber5'of 9

( 7 Consulting Engineers & Geologists, Inc.- B3ORING LOG

' j 812 West Wabash, Eureka, CA ph. (707) 41-8855 fax. (707)411-8877 PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant PROJ. NUMBER: 012125 ELEVATION: 12 feet K13-4 DRILLER: PC Exploration DIAMETER/DEPTH OF BORING:; /186 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/20/12 SAMPLER: Punch Core & SPT LOGGED BY: JPB DATE COMPLETED: 8/30112 2ft~)4AJ SAMP LE~

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--- ---------- -- - - -

POORLY GRADED SAND, olive brown, dense, wet, fine 127 t "5 sand, 10% fines SP POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines 0d-036 120 132 SP POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines Bd-037 Grades to bluish black (GLEY 2 10B 2.511) at 123' SP POORLY GRADED SAND, olive brown, dense, wet, fine 125 sand, 10% fines 137 T SP POORLY GRADED SAND, olive brown, dense, wet, fine 0d-038 sand, 10% fines, massive 142 -t 130 SP POORLY GRADED SAND, olive brown, dense, wet, fine sand, 10% fines, massive SP POORLY GRADED SAND, olive brown, dense, wet, fine BORING LOG Page Number 6of 9

Consulting Engineers & Geologists, Inc.

.. U . 1312 West Wabash, Eureka, CA ph. (707) 441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING: 186 Feet BGS DRILLING METHOD: Mud Rotary SAMPLER: Punch Core & SPT DATE STARTED:

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T, POORLY GRADED SAND, bluish black (GLEY 2 10B 2.5/1), dense, wet, fine to medium sand, 5-10% fines, massive Bd-040 150 Bd-162 041 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' 155 167 BORING LOG Page Number 7 of 9

Consulting Engineers & Geologists, Inc. BORING LOG 4t 812 West Wabash, Eureka, CA ph. (707)-441-8855 fax. (707) 441-8877 PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DRILLING METHOD: Mud Rotary DIAMETER/DEPTH OF BORING:

DATE STARTED: 8/20/12

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r, Contact based on drilling performance 3" gravel clast in sampler 160 172 WELL GRADED GRAVEL WITH SAND, dense, wet, fine to 042 coarse A lot of fine gravel in cuttings Contact based on drillers comments 165 (SILT/CLAY), show has SW with fine grave, rare light gray, 177 very fine sand (SMIML) (bag sample)

043 SILT, very dark greenish gray (GLEY 1 5GY 2.5/1), stiff to Bd- very stiff, moist, 5-10% sand, occasional shell fragments 3.5 045 3.0 4.0 24A4 11 Bd- 4.5 045 SILT/CLAY, very dark greenish gray, very stiff, moist, 3.75 Od- clayey and silty interbeds (crude), zones of abundant shell

.048 4.5 25:6 17 fragments 182 t 170 Bd-047 >4.5

4.0 Ad-049 SILT/CLAY, very dark greenish gray, very stiff, moist, clayey and silty interbeds (crude), less common shell '3.5 B&-

040 fragments 4.0 Bd-' >4.5 050 Bd-Interbedded silt, silt with sand (?) and clay, beds typically 0.25 to 1" thick >4.5 051 175 >4.5 187 Bd- >4.5 053 8d-064.

BORING LOG Page Number 8of 9

Consulting Engineers & Geologists, Inc.

42IT 812 West Wabash, Eureka, CA ph. (707)441-8855 fax. (707) 441-8877 BORING LOG PROJ. NAME: HBPP Slurry Wall LOCATION: Humboldt Bay Power Plant KB-4 PROJ. NUMBER: 012125 ELEVATION: 12 feet DRILLER: PC Exploration DIAMETER/DEPTH OF BORING:_ I 86 Feet BGS DRILLING METHOD: Mud Rotary DATE STARTED: 8/20/12 SAMPLER: Punch Core & SPT DATE COMPLETED: 8/30/12 LOGGED BY: JPB 192 Grades to clayey with depth, same interbeds with predominately clay 197 202 207 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\ 2012\012125-HBPPSlurryWaI\ 100-HydologAssess\ 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\ 2012\ 01 2125-H BPPS~urryWaU1\ 10O-HydologAssess\ PUBS\ rpts\20120815-HydroAssmt. 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 0.0206 hours 1.223545e-4 weeks 2.8157e-5 months ) during each study.

The results of these studies are discussed in a Tidal Influence Study of Unit 3 Area, Humboldt Bay Power Plant, Eureka, Californiadated 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\ 2012\012125-HBPPSlurryWaU\ 100-HydologAssess\ 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 . Figures ....... ."

References Cited Pacific Gas & Electric Company, Geosciences. (December 27, 2002). Technical Report TR-HBIP-2002-01, Seismic HazardAssessment 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.

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EXPLAMAiTIO 2

UITHOLOGY: SYMBOLS:

E RYR FO RNED -EWDS

/ W7ERVY LOW PMVLRWC/Y sL 7 FlME- OR 0

DRE5RL0Wr7?Y

A 6RA44?NE SEDMil-A00DEMMTO1 LOW PERMM&WUY

- Lmonto=r coiffrcr j QUM" WA m

0 0

KRY M~WPMHE WWLI7 MAMREENINTEWA OF 5t'UOE P54 IIPMT (2"Q) LOCATION OF A-A' RELATIVE TO REGIONAL SETTING g

I r -1 77INY LAMIM~ DVV/7Y LW)UJA.M DEPWh Pacific Gas & Electric Humboldt Bay Power Plant Eureka, California Geologic Cross Section A-A' with Proposed Slurry Wall SHN 012125 LJ aREN AL7EhMW77P SIUlY & SAPDY Consulting FEngineers I Figure 3

& GKologi sts, Inc. July, 2012 II 012125-XSEC 012125 XSEC1-5B 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 Pacific Gas & Electric Regional Cross Section Humboldt Bay Power Plant with Proposed Slurry Wall Eureka, California SHN 012125 Consulting ngineers Inc. 1

& Geologsts, IJu.ly, 2012 la~y, 2012 I mn25-xsEc~r-aBI I Figure iur3 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 Week 3 Week 4-17 200 ,

10000 CY Slur.Ex.....

1000 CY 1000 CY Slurry Exc. Slurry Exc.

Week 18 Week 19 Week 20 Week 21 200 C 3000 CY

. .. .......

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

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

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

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

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

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

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

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

1000 CY 1000 CY Offsite

Caisson Excavation Stockpile Based on 25 Intermodal Load-out/Week Lift I Lift 2 Lift 3 Weeks 1-4 Weeks 5-8 Weeks 9-12 rnhtV flr fly

.600C 1000 CY Week' fo-e. to 1000 CY

0

Week' ':Results ::::::;::'

1000 CY t

W.. .. .. .. .. .. .. .. .. . .

Wee...1......t...

..... .... . . .... ... .... l Load-out to Load-out to We.......o...to Intermodal Load-out to Intermodal .... ... ... ... Intermodal S.... .....

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

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

- . .1.2.1.12' .1 .2'..

. ,.1" .: 2".. . . . . .

...

. . . .

.i pared to be tamnatedj Lift 4 Lift 10 Lower Lift 5 (LL5)

Weeks 13-16 Weeks 37-40 Weeks 65-70 800 C Continues Per rProcess Spreadsheet 200S I

F 1000 CY Load-out to Wek~k 16-: Jhoe)Ito....li::::i A poWpriate

.... .....:...

I Wee.

.. ,.*.*.,

Week.....

...

,*,.....

... eek. ol..

.. .. x ...

. :.:.:.:..

x .x.: . . .I

..........

. ....

......

,.t

...

Intermodal

............ ...... ....... . oae . .. : ......

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

...

. .

Table 6 - Excavation Schedule Phase 1 Upper Caisson Lift 1-10 El +(121to El -(30) Lift1 (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) Lift8 (4 Weeks) lift 9 (4 Weeks) Lift 10 (4 Weeks)

_tart Finish Stan Finish rst-,

e T F-sh .. sh stko I kFinih Fnih St....s Stan I Finish 8F...r In Frsk Finih Startk Finish Elevation 12 6 6 2 2 -- 2 -6 -6 -0 -10 1 -14 -14 1 -18 -18 22 7 -26 -26 -30 C.YRemoved (Avg) 1020 BCYX 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 939 12 03 16 17 20 21 24 25 20 29 32 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 4- 8 6 -73 -73 -80 CYRemoved (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 80SUO

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-sh Start s sh -s Fs 2 Finish C.YRemoved (Avg) 1020 BCYX 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 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 Start. I Finish s .... I Finish _t___ Firntis Stern Start I Finish Elevation -301 -34 -44 -481 -61 -6_73 -3 8 C.YRemoved )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

ML14128A369

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