ULNRC-06349, Callaway, Unit 1 - Enclosure 3 - Document A22-1690-001, Rev. 0, Decommissioning Cost Analysis for the Callaway Energy Center, Decommissioning Alternatives, Section 2, Pages 1 of 12 - Section 3 Page 13 of 30

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Callaway, Unit 1 - Enclosure 3 - Document A22-1690-001, Rev. 0, Decommissioning Cost Analysis for the Callaway Energy Center, Decommissioning Alternatives, Section 2, Pages 1 of 12 - Section 3 Page 13 of 30
ML17097A560
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Issue date: 03/16/2015
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ULNRC-06349 A22-1690-001, Rev. 0
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ULNRC-06349 Page 26 of 173 Caflaway Energy Center*Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 1 of 12 2.DECOMMISSIONING ALTERNATIVES Detailed cost estimates were developed to decommission Callaway for the approved decommissioning alternatives:

DECON and SAF$TOR.Although the alternatives differ with respect to technique, process, cost, and schedule, they attain the same result: the ultimate release of the site for unrestricted use.The DECON and SAFSTOR alternatives were evaluated for both a 40-year and 60-year operating license since the application for license renewal is still in review.Two disposal options were also evaluated:

recycling and direct disposal.Recycling is presented as the base option and considers the off-site processing of plant equipment and commodities with low levels of radiological contamination andlor material suspected to be contaminated for volume reduction prior to disposaL The direct disposal option assumes that all contaminated and suspect material is packaged at the site for disposal at a regulated disposal facility.The scenarios are summarized as follows.Plant Low-Level Alternative Operating Radioactive Waste Cost Summaries and/or Life (years)Options Detailed Estimates DECON 40 Reycing Sections 3, 6, Appendix C Direct Disposal Appendix E SAFSTOR 40 Recycling Sections 3, 6, Appendix D Direct Disposal Appendix F DECON 60 Recycling Appendix 0 SAF$TOR 60 Recycling Appendix H The following sections describe the basic activities associated with each alternative.

Although detailed procedures for each activity identified are not provided, and the actual sequence of work may vary, the activity descriptions provide a basis not only for estimating but also for the expected scope of work, i.e., engineering and planning at the time of decommissioning.

The conceptual approach that the NRC has described in its regulations divides decommissioning into three phases.The initial phase commences with the effective date of permanent cessation of operations and involves the transition of both plant and licensee from reactor operations (i.e., power production) to facility de-activation and closure.During the first phase, notification is to be provided to the NRC certifying the permanent cessation of operations and the removal of fuel from the reactor vessel.The licensee is then prohibited from reactor operation.

TLG Services, Inc.

ULNRC-06349 Page 27 of 173 Callaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 2 of 12 The second phase encompasses activities during the storage period or during major decommissioning activities, or a combination of the two.The third phase pertains to the activities involved in license termination.

The decommissioning estimates developed for Callaway are also divided into phases or periods;however, demarcation of the phases is based upon major milestones within the project or significant changes in the projected expenditures.

2.1 DECON The DECON alternative, as defined by the NRC, is'the alternative in which the equipment, structures, and portions of a facility and site containing radioactive contaminants are removed or decontaminated to a level that permits the property to be released for unrestricted use shortly after cessation of operations."

This study does not address the cost to dispose of the spent fuel residing at the site;such costs are funded through a surcharge on electrical generation.

The study also assumes that the costs incurred with the interim on-site storage of the fuel, pending shipment by the DOE to an off-site disposal facility, are fully reimbursable.

2.1.1 Period 1-Preparations In anticipation of the cessation of plant operations, detailed preparations are undertaken to provide a smooth transition from plant operations to site decommissioning.

Through implementation of a staffing transition plan, the organization required to manage the intended decommissioning activities is assembled from available plant staff and outside resources.

Preparations include the planning for permanent defueling of the reactor, revision of technical specifications applicable to the operating conditions and requirements, a characterization of the facility and major components, and the development of the P$DAR.Engineering and Planning The PSDAR, required within two years of the notice to cease operations, provides a description of the licensee's planned decommissioning activities, a timetable, and the associated financial requirements of the intended decommissioning program.Upon receipt of the P$DAR, the NRC wifi make the document available to the public for comment in a local hearing to be held in the vicinity of the reactor site.Ninety days following submittal and NRC receipt of the P$DAR, the licensee may begin to perform major decommissioning activities under a modified 10 CFR§50.59 procedure, i.e., without specific NRC approval.Major TLG Services, Inc.

ULNRC-06349 Page 28 of 773 Callaway Energy Center Document A22-1690-OO1, Rev.U Decommissioning Cost Analysis Section 2, Page 3 of 12 activities are defined as any activity that results in permanent removal of major radioactive components, permanently modifies the structure of the containment, or results in dismantling components (for shipment)containing GTCC, as defined by 10 CFR§61.Major components are further defined as comprising the reactor vessel and internals, large bore reactor coolant system piping, and other large components that are radioactive.

The NRC includes the following additional criteria for use of the§50.59 process in decommissioning.

The proposed activity must not:.foreclose release of the site for possible unrestricted use,.significantly increase decommissioning costs,.cause any significant environmental impact, or.violate the terms of the licensee's existing license.Existing operational technical specifications are reviewed and modified to reflect plant conditions and the safety concerns associated with permanent cessation of operations.

The environmental impact associated with the planned decommissioning activities is also considered.

Typically, a licensee wifi not be allowed to proceed if the consequences of a particular decommissioning activity are greater than that bounded by previously evaluated environmental assessments or impact statements.

In this instance, the licensee would have to submit a license amendment for the specific activity and update the environmental report.The decommissioning program outlined in the P$DAR will be designed to accomplish the required tasks within the ALARA guidelines (as defined in 10 CFR§20)for protection of personnel from exposure to radiation hazards.It will also address the continued protection of the health and safety of the public and the environment during the dismantling activity.Consequently, with the development of the P$DAR, activity specifications, cost-benefit and safety analyses, work packages and procedures, would be assembled to support the proposed decontamination and dismantling activities.

Site Preparations Following final plant shutdown, and in preparation for actual decommissioning activities, the following activities are initiated:

.Characterization of the site and surrounding environs.This includes radiation surveys of work areas, major components (incluthng the TLG Services, Inc.

ULNRC-06349 Page 29 of 173 Caltaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 4 of 12 reactor vessel and its internals), internal piping, and primary shield cores..Isolation of the spent fuel storage pooi and fuel handling systems, such that decommissioning operations can commence on the balance of the plant.The pool will remain operational for approximately five and one-half years following the cessation of operations before the inventory resident at shutdown can be transferred to the I$FSI..Specification of transport and disposal requirements for activated materials andlor hazardous materials, including shielding and waste stabilization.

.Development of procedures for occupational exposure control, control and release of liquid and gaseous effluent, processing of radwaste (including dry-active waste, resins, filter media, metallic and non-metallic components generated in decommissioning), site security and emergency programs, and industrial safety.2.1.2 Period 2-Decommissioning Operations This period includes the physical decommissioning activities associated with the removal and disposal of contaminated and activated components and structures, including the successful termination of the 10 CFR§50 operating license.Significant decommissioning activities in this phase include:.Construction of temporary facilities andfor modification of existing facilities to support dismantling activities.

This may include a centralized processing area to facilitate equipment removal and component preparations for off-site disposal..Reconfiguration and modification of site structures and facilities as needed to support decommissioning operations.

This may include the upgrading of roads (on-and off-site)to facilitate hauling and transport.

Modifications may be required to the containment structure to facilitate access of large/heavy equipment.

Modifications may also be required to the refueling area of the building to support the segmentation of the reactor vessel internals and component extraction.

.Design and fabrication of temporary and permanent shielding to support removal and transportation activities, construction of contamination control envelopes, and the procurement of specialty tooling.TLG Services, Inc.

ULNRC-06349 Page 30 of 173 Callaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 5 of 12.Procurement (lease or purchase)of shipping canisters, cask liners, and industrial packages for the disposition of low-level radioactive waste..Decontamination of components and piping systems as required to control (minimize) worker exposure..Removal of piping and components no longer essential to support decommissioning operations.

.Removal of control rod drive housings and the head service structure from the reactor vessel head.Segmentation of the vessel closure head..Removal and segmentation of the upper internals assemblies.

Segmentation will maximize the loading of the shielded transport casks, i.e., by weight and activity.The operations are conducted under water using remotely operated tooling and contamination controls..Disassembly and segmentation of the remaining reactor internals, including the core shroud and lower core support assembly.Some material is expected to exceed Class C disposal requirements.

As such, the segments will be packaged in modified fuel storage canisters for geologic disposal..Segmentation of the reactor vessel.A shielded platform is installed for segmentation as cutting operations are performed in-air using remotely operated equipment within a contamination control envelope.The water level is maintained just below the cut to minimize the working area dose rates.Segments are transferred in-air to containers that are stored under water, for example, in an isolated area of the refueling canal..Removal of the activated portions of the concrete biological shield and accessible contaminated concrete surfaces.If dictated by the steam generator and pressurizer removal scenarios, those portions of the associated cubicles necessary for access and component extraction are removed..Removal of the steam generators and pressurizer for material recovery and controlled disposal.The generators will be moved to an on-site processing center, the steam domes removed and the internal components segregated for recycling.

The lower shell and tube bundle will be packaged for direct disposal.These components can serve as their own burial containers provided that all penetrations are properly sealed and the internal contaminants are stabilized, e.g., with grout.Steel shielding will be added, as necessary, to those TLG Services, Inc.

ULNRC-06349 Page3l of 173 CaUaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 6 of 12 externa'areas of the package to meet transportation limits and regulations.

The pressurizer is disposed of intact.At least two years prior to the anticipated date of license termination, an LTP is required.Submitted as a supplement to the Final Safety Analysis Report (F$AR)or its equivalent, the plan must include: a site characterization, description of the remaining dismantling activities, plans for site remethation, procedures for the final radiation survey, designation of the end use of the site, an updated cost estimate to complete the decommissioning, and any associated environmental concerns.The NRC will notice the receipt of the plan, make the plan available for public comment, and schedule a local hearing.LTP approval will be subject to any conditions and limitations as deemed appropriate by the Commission.

The licensee may then commence with the final remediation of site facilities and services, including:

.Removal of remaining plant systems and associated components as they become nonessential to the decommissioning program or worker health and safety (e.g., waste collection and treatment systems, electrical power and ventilation systems)..Removal of the steel liners from refueling canal, disposing of the activated and contaminated sections as radioactive waste.Removal of any activatedl contaminated concrete..Surveys of the decontaminated areas of the containment structure.

.Remediation and removal of the contaminated equipment and material from the fuel building and any other contaminated facility.Rathation and contamination controls will be utilized until residual levels indicate that the structures and equipment can be released for unrestricted access and conventional demolition.

This activity may necessitate the dismantling and disposition of most of the systems and components (both clean and contaminated) located within these bmlthngs.This activity facilitates surface decontamination and subsequent verification surveys required prior to obtaining release for demolition.

.Routing of material removed in the decontamination and dismantling to a central processing area.Material certified to be free of contamination is released for unrestricted disposition, e.g., as scrap, recycle, or general disposal.Contaminated material is characterized and segregated for additional off-site processing (disassembly, chemical cleaning, volume reduction, and waste treatment), andlor TLG Services, Inc.

ULNRC-06349 Page 32 of 173 Callaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 7 of 12 packaged for controlled disposal at a low-level radioactive waste disposal facility.Incorporated into the LTP is the Final Survey Plan.This plan identifies the radiological surveys to be performed once the decontamination activities are completed and is developed using the guidance provided in the"Multi-Agency Radiation Survey and Site Investigation Manual (J55J}jf)"[16J This document incorporates the statistical approaches to survey design and data interpretation used by the EPA.It also identifies state-of-the-art, commercially available instrumentation and procedures for conducting radiological surveys.Use of this guidance ensures that the surveys are conducted in a manner that provides a high degree of confidence that applicable NRC criteria are satisfied.

Once the survey is complete, the results are provided to the NRC in a format that can be verified.The NRC then reviews and evaluates the information, performs an independent confirmation of radiological site conditions, and makes a determination on the requested change to the operating license (that would release the property, exclusive of the ISFSI, for unrestricted use).The NRC will amend the operating licenses if it determines that site remethation has been performed in accordance with the LTP, and that the terminal radiation survey and associated documentation demonstrate that the property (exclusive of the ISFSI)is suitable for release.2.1.3 Period 3-Site Restoration Following completion of decommissioning operations, site restoration activities will begin.Efficient removal of the contaminated materials and verification that residual radionuclide concentrations are below the NRC limits will result in substantial damage to many of the structures.

Although performed in a controlled, safe manner, blasting, coring, drilling, scarification (surface removal), and the other decontamination activities will substantially degrade power block structures including the reactor, fuel handling, and radioactive waste buildings.

Under certain circumstances, verifying that subsurface rathonucide concentrations meet NRC site release requirements will require removal of grade slabs and lower floors, potentially weakening footings and structural supports.This removal activity wifi be necessary for those facilities and plant areas where historical records, when available, indicate the potential for rathonucides having been present in the soil, where system failures have been recorded, or where it is required to TLG Services, Inc.

ULNRC-06349 Page 33 of 173 Callaway Energy Center Document A22-1690-OO1, RevS 0 Decommissioning Cost Analysis Section 2, Page 8 of 12 confirm that subsurface process and drain lines were not breached over the operating life of the station.Immediate dismantling of site structures is clearly the most appropriate and cost-effective option.It is unreasonable to anticipate that these structures would be repaired and preserved after the radiological contamination is removed.The cost todismantle site structures with a work force already mobilized on site is more efficient than if the process were deferred.Site facilities quickly degrade without maintenance, adding additional expense and creating potential hazards to the public as well as to future workers.Abandonment creates a breeding ground for vermin infestation as well as other biological hazards.This cost study presumes that non-essential structures and site facilities are dismantled as a continuation of the decommissioning activity.Foundations and exterior walls are removed to a nominal depth of three feet below grade.The three-foot depth allows for the placement of gravel for drainage, as well as topsoil, so that vegetation can be established for erosion control.Site areas affected by the dismantling activities are restored and the plant area graded as required to prevent ponthng and inhibit the refloating of subsurface materials.

Non-contaminated concrete rubble produced by demolition activities is processed to remove reinforcing steel and miscellaneous embedments.

The processed material is then used on site to backfill foundation voids.Excess non-contaminated materials are trucked to an off-site area for disposal as construction debris.2.2 SAFSTOR The NRC defines SAF$TOR as"the alternative in which the nuclear facility is placed and maintained in a condition that allows the nuclear facility to be safely stored and subsequently decontaminated (deferred decontamination) to levels that permit release for unrestricted use."The facility is left intact (during the dormancy period), with structures maintained in a sound condition.

Systems that are not required to support the spent fuel pool or site surveillance and security are drained, de-energized, and secured.Minimal cleaning/removal of loose contamination andior fixation and sealing of remaining contamination is performed.

Access to contaminated areas is secured to provide controlled access for inspection and maintenance.

The engineering and planning requirements are similar to those for the DECON alternative, although a shorter time period is expected for these TLG Services, Inc.

ULNRC-06349 Page 34 of 173 Callaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 9 of 12 activities due to the more limited work scope.Site preparations are also similar to those for the DECON alternative.

However, with the exception of the required radiation surveys and site characterizations, the mobilization and preparation of site facilities is less extensive.

2.2.1 Period 1-Preparations Preparations for long-term storage include the planning for permanent defueling of the reactor, revision of technical specifications appropriate to the operating conditions and requirements, a characterization of the facility and major components, and the development of the P$DAR.The process of placing the plant in safe-storage includes, but is not limited to, the following activities:

.Isolation of the spent fuel storage services and fuel handling systems so that safe-storage operations may commence on the balance of the plant.This activity may be carried out by plant personnel in accordance with existing operating technical specifications.

Activities are scheduled around the fuel handling systems to the greatest extent possible..Transfer of the spent fuel from the storage pool to the I$FSI following the minimum required cooling period..Draining and de-energizing of the non-contaminated systems not required to support continued site operations or maintenance.

.Disposing of contaminated ifiter elements and resin beds not required for processing wastes from layup activities for future operations.

.Draining of the reactor vessel, with the internals left in place and the vessel head secured..Draining and de-energizing non-essential, contaminated systems with decontamination as required for future maintenance and inspection.

.Preparing lighting and alarm systems whose continued use is required;de-energizing portions of fire protection, electric power, and HVAC systems whose continued use is not required..Cleaning of the loose surface contamination from building access pathways..Performing an interim radiation survey of plant, posting warning signs where appropriate.

TLG Services, Inc.

ULNRC-06349 Page 35 of 173 Caflaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis*Section 2, Page 10 of 12.Erecting physical barriers and/or securing all access to radioactive or contaminated areas, except as required for inspection and maintenance.

I Installing security and surveillance monitoring equipment and relocating security fence around secured structures, as required.2.2.2 Period 2-Dormancy The second phase identified by the NRC in its rule addresses licensed activities during a storage period and is applicable to the dormancy phases of the deferred decommissioning alternatives.

Dormancy activities include a 24-hour security force, preventive and corrective maintenance on security systems, area lighting, general building maintenance, heating and ventilation of buildings, routine radiological inspections of contaminated structures, maintenance of structural integrity, and a site environmental and radiation monitoring program.Resident maintenance personnel perform equipment maintenance, inspection activities, routine services to maintain safe conditions, adequate lighting, heating, and ventilation, and periodic preventive maintenance on essential site services.An environmental surveillance program is carried out during the dormancy period to ensure that releases of radioactive material to the environment are prevented andlor detected and controlled.

Appropriate emergency procedures are established and initiated for potential releases that exceed prescribed limits.The environmental surveillance program constitutes an abbreviated version of the program in effect during normal plant operations.

Security during the dormancy period is conducted primarily to prevent unauthorized entry and to protect the public from the consequences of its own actions.The security fence, sensors, alarms, and other surveillance equipment provide security.Fire and radiation alarms are also monitored and maintained.

Consistent with the DECON scenario, the spent fuel storage pool is emptied within five and one-half years of the cessation of operations.

The pool is secured for storage and decommissioned along with the power block structures in Period 4.After a period of storage (such that license termination is accomplished within 60 years of final shutdown), it is required that the licensee TLG Services, Inc.

ULNRC-06349 Page 36 of 173 Caflaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 11 of 12 submit an application to terminate the license, along with an LTP (described in Section 2.1.2), thereby initiating the third phase.2.2.3 Periods 3 and 4-Delayed Decommissioning Prior to the commencement of decommissioning operations, preparations are undertaken to reactivate site services and prepare for decommissioning.

Preparations include engineering and planning, a detailed site characterization, and the assembly of a decommissioning management organization.

Final planning for activities and the writing of activity specifications and detailed procedures are also initiated at this time.Much of the work in developing a termination plan is relevant to the development of the detailed engineering plans and procedures.

The activities associated with this phase and the follow-on decontamination and dismantling processes are detailed in Sections 2.1.1 and 2.1.2.The primary difference between the sequences anticipated for the DECON and this deferred scenario is the absence, in the latter, of any constraint on the availability of the fuel storage facilities for decommissioning.

Variations in the length of the dormancy period are expected to have little effect upon the quantities of radioactive wastes generated from system and structure removal operations.

Given the levels of radioactivity and spectrum of radionucides expected from forty (or sixty)years of plant operation, no plant process system identified as being contaminated upon final shutdown will become releasable due to the decay period alone, i.e., there is no significant reduction in the waste generated from the decommissioning activities.

However, due to the lower activity levels, a greater percentage of the waste volume can be designated for off-site processing and recovery.The delay in decommissioning also yields lower working area radiation levels.As such, the estimate for this delayed scenario incorporates reduced ALARA controls for the$AF$TORs lower occupational exposure potential.

Although the initial radiation levels due to GoCo will decrease during the dormancy period, the internal components of the reactor vessel wifi still exhibit sufficiently high radiation dose rates to require remote sectioning under water due to the presence of long-lived rathonuclides such as 9Ni, and 63Ni.Therefore, the thsmantling procedures described for the DECON alternative would still be employed during TLG Services, Inc.

ULNRC-06349 Page 37 of 173 Caflaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 2, Page 12 of 12 this scenario.Portions of the biological shield wifi still be radioactive due to the presence of activated trace elements with long half-lives

('52Eu and'54Eu).Decontamination will require controlled removal and disposal.It is assumed that radioactive corrosion products on inner surfaces of piping and components will not have decayed to levels that will permit unrestricted use or allow conventional removal.These systems and components will be surveyed as they are removed and disposed of in accordance with the existing radioactive release criteria.2.2.4 Period 5-Site Restoration Following completion of decommissioning operations, site-restoration activities can begin.Dismantling, as a continuation of the decommissioning process, is clearly the most appropriate and cost-effective option, as described in Section 2.1.3.The basis for the dismantling cost in this scenario is consistent with that described for DECON, presuming the removal of structures and site facilities to a nominal depth of three feet below grade and the limited restoration of the site.TLG Services, Inc.

ULNRC-06349 Page 38 of 173 Caflaway Energy Center Document A224690-OO1, Rev.U Decommissioning Cost Analysis Section 3, Page 1 of 30 3.COST ESTIMATE The cost estimates prepared for decommissioning Callaway consider the unique features of the site, including the N$S$, power generation systems, support services, site buildings, and ancillary facilities.

The basis of the estimates, including the sources of information relied upon, the estimating methodology employed, site-specific considerations, and other pertinent assumptions, is described in this section.3.1 BASIS OF ESTIMATE The estimate's were developed using the site-specific, technical information from the 201 1 analysis.This information was reviewed for the current analysis and updated as deemed appropriate.

The site-specific considerations and assumptions used in the previous evaluation were also revisited.

Modifications were incorporated where new information was available or experience from previously completed decommissioning programs provided viable alternatives or improved processes.

3.2 METHODOLOGY

The methodology used to develop the estimates follows the basic approach originally presented in the MF/NE$P-036 study report,"Guidelines for Producing Commercial Nuclear Power Plant Decommissioning Cost Estimates,"[17]and the DOE"Decommissioning Handbook."['81 These documents present a unit factor method for estimating decommissioning activity costs, which simplifies the estimating calculations.

Unit factors for concrete removal ($/cubic yard), steel removal ($/ton), and cutting costs ($/inch)are developed using local labor rates.The activity-dependent costs are estimated with the item quantities (cubic yards and tons), developed from plant drawings and inventory documents.

Removal rates and material costs for the conventional disposition of components and structures rely upon information available in the industry publication,"Building Construction Cost Data,"published by R.S.Means.['9]

The unit factor method provides a demonstrable basis for establishing reliable cost estimates.

The detail provided in the unit factors, including activity duration, labor costs (by craft), and equipment and consumable costs, ensures that essential elements have not been omitted.Appendix A presents the detailed development of a typical unit factor.Appendix B provides the values contained within one set of factors developed for this analysis.TLG Services, Inc.

ULNRC-06349 Page 39 of 173 Catlaway Energy Center Document A22-1690-OO1, Rev.0.Decommissioning Cost Analysis Section 3, Page 2 of 30 This analysis reflects lessons learned from TLG's involvement in the$hippingport Station Decommissioning Project, completed in 1989, as well as the decommissioning of the Cintichem reactor, hot cells, and associated facilities, completed in 1997.In addition, the planning and engineering for the Pathfinder, Shoreham, Rancho$eco, Trojan, Yankee Rowe, Big Rock Point, Maine Yankee, Humboldt Bay-3, Oyster Creek, Connecticut Yankee, and San Onofre-1 nuclear units have provided additional insight into the process, the regulatory aspects, and the technical challenges of decommissioning commercial nuclear units.Work Difficulty Factors TLG has historically applied work difficulty adjustment factors (WDFs)to account for the inefficiencies in working in a power plant environment.

WDFs are assigned to each unique set of unit factors, commensurate with the inefficiencies associated with working in confined, hazardous environments.

The ranges used for the WDFs are as follows:.Access Factor 10%to 20%.Respiratory Protection Factor 10%to 50%.Radiation/ALARA Factor 10%to 37%.Protective Clothing Factor 10%to 30%.Work Break Factor 8.33%The factors and their associated range of values were developed in conjunction with the AIF/NESP-036 study.The application of the factors is discussed in more detail in that publication.

Scheduling Program Durations The unit factors, adjusted by the WDFs as described above, are applied against the inventory of materials to be removed in the radiological controlled areas.The resulting man-hours, or crew-hours, are used in the development of the decommissioning program schedule, using resource loading and event sequencing considerations.

The scheduling of conventional removal and dismantling activities is based upon productivity information available from the'Building Construction Cost Dat&publication.

An activity duration critical path is used to determine the total decommissioning program schedule.The schedule is relied upon in calculating the carrying costs, which include program management, administration, field TLG Services, Inc.

ULNRC-06349 Page 40 of 173 Caflaway Energy Center.Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 3 of 30 engineering, equipment rental, and support services such as quality control and security.This systematic approach for assembling decommissioning estimates ensures a high degree of confidence in the reliability of the resulting costs.3.3 FINANCIAL COMPONENTS OF THE COST MODEL TLG's proprietary decommissioning cost model, DECCER, produces a number of distinct cost elements.These direct expenditures, however, do not comprise the total cost to accomplish the project goal, i.e., license termination and site restoration.

Inherent in any cost estimate that does not rely on historical data is the inability to specify the precise source of costs imposed by factors such as tool breakage, accidents, ifinesses, weather delays, and labor stoppages.

In the DECCER cost model, contingency fulfills this role.Contingency is added to each line item to account for costs that are difficult or impossible to develop analytically.

Such costs are historically inevitable over the duration of a job of this magnitude; therefore, this cost analysis includes funds to cover these types of expenses.3.3.1 Contingency The activity-and period-dependent costs are combined to develop the total decommissioning cost.A contingency is then applied on a line-item basis, using one or more of the contingency types listed in the MF/NE$P-036 study."Contingencies" are defined in the American Association of Cost Engineers"Project and Cost Engineers' Handbook"[201 as"specific provision for unforeseeable elements of cost within the defined project scope;particularly important where previous experience relating estimates and actual costs has shown that unforeseeable events which will increase costs are likely to occur."The cost elements in this analysis are based upon ideal conditions and maximum efficiency; therefore, consistent with industry practice, contingency is included.In the MF/NESP-036 study, the types of unforeseeable events that are likely to occur in decommissioning are discussed and guidelines are provided for percentage contingency in each category.It should be noted that contingency, as used in this analysis, does not account for price escalation and inflation in the cost of decommissioning over the remaining operating life of the station.Contingency funds are an integral part of the total cost to complete the decommissioning process.Exclusion of this component puts at risk a TLG Services, Inc.

ULNRC-06349 Page 41 of 173 Callaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 4 of 30 successful completion of the intended tasks and, potentially, subsequent related activities.

For this study, TLG examined the major activity-related problems (decontamination, segmentation, equipment handling, packaging, transport, and waste disposal)that necessitate a contingency.

Individual activity contingencies ranged from 10%to 75%, depending on the degree of difficulty judged to be appropriate from TLG's actual decommissioning experience.

The contingency values used in this study are as follows:.Decontamination 50%.Contaminated Component Removal 25%.Contaminated Component Packaging 10%.Contaminated Component Transport 15%.Low-Level Radioactive Waste Disposal 25%.Low-Level Radioactive Waste Processing 15%.Reactor Segmentation 75%.NSS$Component Removal 25%.Reactor Waste Packaging 25%.Reactor Waste Transport 25%.Reactor Vessel Component Disposal 50%.GTCC Disposal 15%.Non-Radioactive Component Removal 15%.Heavy Equipment and Tooling 15%.Supplies 25%.Engineering 15%S Energy 15%.Insurance, Taxes and Fees 10%.Staffing 15%.Characterization and Termination Surveys 30%.Construction 15%.Spent Fuel Storage System Loading/Transfer Costs 15%.Operations and Maintenance Expenses 15%The contingency values are applied to the appropriate components of the estimates on a line item basis.A composite value is then reported at the end of each detailed estimate (as provided in the appendices).

For example, the composite contingency value reported for the DECON alternative in Appendix C is approximately 18.9%;the corresponding SAF$TOR alternative in Appendix D is approximately 17.2%.TLG Services, Inc.

ULNRC-06349 Page 42 of 173 CaflawayEnergy Center DocumentA22-1690-OO1, Rev.0 Decommissioning Cost Anaiysis Section 3, Page 5 of 30 3.3.2 Financial Risk In addition to the routine uncertainties addressed by contingency, another cost element that is sometimes necessary to consider when bounding decommissioning costs relates to uncertainty, or risk.Examples can include changes in work scope, pricing, job performance, and other variations that could conceivably, but not necessarily, occur.Consideration is sometimes necessary to generate a level of confidence in the estimate, within a range of probabilities.

TLG considers these types of costs under the broad term"financial risk."Included within the category of financial risk are:.Transition activities and costs: ancillary expenses associated with eliminating 50%to 80%of the site labor force shortly after the cessation of plant operations, added cost for worker separation packages throughout the decommissioning program, national or company-mandated retraining, and retention incentives for key personnel.

S Delays in approval of the decommissioning plan due to intervention, public participation in local community meetings, legal challenges, and national and local hearings..Changes in the project work scope from the baseline estimate, involving the discovery of unexpected levels of contaminants, contamination in places not previously expected, contaminated soil previously undiscovered (either radioactive or hazardous material contamination), variations in plant inventory or configuration not indicated by the as-built drawings..Regulatory changes, for example, affecting worker health and safety, site release criteria, waste transportation, and disposal..Policy decisions altering national commitments (e.g., in the ability to accommodate certain waste forms for disposition), or in the timetable for such, for example, the start and rate of acceptance of spent fuel by the DOE..Pricing changes for basic inputs such as labor, energy, materials, and disposal.Items subject to widespread price competition (such as materials) may not show significant variation; however, others such as waste disposal could exhibit large pricing uncertainties, particularly in markets where limited access to services is available.

This cost study, however, does not add any additional costs to the estimate for financial risk, since there is insufficient historical data from TLG Services, Inc.

ULNRC-06349 Page 43 of 173 Callaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 6 of 30 which to project future liabilities.

Consequently, the areas of uncertainty or risk are revisited periothcally and addressed through repeated revisions or updates of the base estimates.

3.4 SITE-SPECIFIC CONSIDERATIONS There are a number of site-specific considerations that affect the method for dismantling and removal of equipment from the site and the degree of restoration required.The cost impact of the considerations identified below is included in this cost study.3.4.1 Spent Fuel Management The cost to dispose the spent fuel generated from plant operations is not reflected within the estimates to decommission Callaway.Ultimate disposition of the spent fuel is within the province of the DOE's Waste Management System, as defined by the Nuclear Waste Policy Act.As such, the disposal cost is financed by a 1 milllkWhr surcharge paid into the DOE's waste fund during operations.

However, the NRC requires licensees to establish a program to manage and provide funding for the management of all irradiated fuel at the reactor until title of the fuel is transferred to the Secretary of Energy.This funding requirement is fulfilled through inclusion of certain high-level waste cost elements within the estimates, as described below.For estimating purposes, Ameren Missouri has assumed that all spent fuel will be relocated to an ISFSI on the Callaway site within five and one-half years after shutdown.This will allow Ameren Missouri to proceed with decommissioning (or safe-storage) operations in the shortest time possible.It is assumed that the five and one-half years provides the necessary cooling period for the final core to meet storage requirements for decay heat.Once the pool is emptied, the spent fuel storage and handling facilities are available for decommissioning.

Operation and maintenance costs for the spent fuel pool are included within the estimate.Canister Loading and Transfer The estimates include the cost for the labor and equipment to load and transfer the spent fuel assemblies projected to reside in the pool at the cessation of plant operations.

The capital cost associated with the dry storage system is not included in the estimates.

TLG Services, Inc.

ULNRC-06349 Page 44 of 173 Callaway Energy Center*Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 7 of 30 Operations and Maintenance The estimates include the cost of operating and maintaining the spent fuel pool for approximately five and one half years after the cessation of operations.

It is assumed that the five and one-half years provides the necessary cooling period for the final core to meet the dry cask storage vendor's system.GTCC The dismantling of the reactor internals is expected to generate radioactive waste considered unsuitable for shallow land disposal (i.e., low-level rathoactive waste with concentrations of rathonuclides that exceed the limits established by the NRC for Class C rathoactive waste (GTCC)).The Low-Level Radioactive Waste Policy Amendments Act of 1985 assigned the federal government the responsibility for the disposal of this material.The Act also stated that the beneficiaries of the activities resulting in the generation of such radioactive waste bear all reasonable costs of disposing of such waste.Although the DOE is responsible for disposing of GTCC waste, any costs for that service have not been determined.

For purposes of this estimate, the GTCC radioactive waste has been assumed to be packaged in the same canisters used to store spent fuel and disposed of as high-level waste, at a cost equivalent to that envisioned for the spent fuel.The number of canisters required and the packaged volume for GTCC was based upon experience at Maine Yankee (e.g., the payload constraints as identified in the canister's certificate of compliance).

It is assumed that the DOE would not accept this waste prior to completing the transfer of spent fuel.Therefore, until such time the DOE is ready to accept GTCC waste, it is assumed that this material would remain in storage at the site (for the DECON alternative).

In the SAFSTOR scenario, the GTCC material is shipped directly to a DOE facility as it is generated since the fuel has been removed from the site prior to the start of decommissioning.

3.4.2 Reactor Vessel and Internal Components The reactor pressure vessel and internal components are segmented for disposal in shielded, reusable transportation casks.Segmentation is performed in the refueling canal, where a turntable and remote cutter are installed.

The vessel is segmented in place, using a mast-mounted cutter supported off the lower head and thrected from a shielded work TLG Services, Inc.

ULNRC-06349 Page 45 of 173 Callaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 8 of 30 platform installed overhead in the reactor cavity.Transportation cask specifications and transportation regulations dictate the segmentation and packaging methodology.

Intact disposal of reactor vessel shells has been successfully demonstrated at several of the sites currently being decommissioned.

Access to navigable waterways has allowed these large packages to be transported to the Barnwell, South Carolina and Hanford, Washington disposal sites with minimal overland travel.Intact disposal of the reactor vessel and internal components can provide savings in cost and worker exposure by eliminating the complex segmentation requirements, isolation of the GTCC material, and transport/storage of the resulting waste packages.Portland General Electric (PGE)was able to dispose of the Trojan reactor as an intact package (including the internals).

However, its location on the Columbia River simplified the transportation analysis since:.the reactor package could be secured to the transport vehicle for the entire journey, i.e., the package was not lifted during transport,.there were no man-made or natural terrain features between the plant site and the disposal location that could produce a large drop, and.transport speeds were very low, limited by the overland transport vehicle and the river barge.As a member of the Northwest Compact, PGE had a site available for disposal of the package-the US Ecology facility in Washington State.The characteristics of this arid site proved favorable in demonstrating compliance with land disposal regulations.

It is not known whether this option will be available when the Callaway ceases operation.

Future viability of this option will depend upon the ultimate location of the disposal site, as well as the disposal site licensee's ability to accept highly radioactive packages and effectively isolate them from the environment.

Consequently, the study assumes the reactor vessel will require segmentation, as a bounding condition.

3.4.3 Primary System Components In the DECON scenario, the reactor coolant system components are assumed to be decontaminated using chemical agents prior to the start TLG Services, Inc.

ULNRC-06349 Page 46 of 173 Caflaway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 9 of 30 of dismantling operations.

This type of decontamination can be expected to have a significant ALARA impact, since in this scenario the removal work is done within the first few years of shutdown.A decontamination factor (average reduction) of 10 is assumed for the process.In the$AFSTOR scenario, rathonuclide decay is expected to provide the same benefit and, therefore, a chemical decontamination is not included.The following discussion deals with the removal and disposition of the steam generators, but the techniques involved are also applicable to other large components, such as heat exchangers, component coolers, and the pressurizer.

The steam generators' size and weight, as well as their location within the reactor building, will ultimately determine the removal strategy.A trolley crane is set up for the removal of the generators.

It can also be used to move portions of the steam generator cubicle walls and floor slabs from the reactor building to a location where they can be decontaminated and transported to the material handling area.Interferences within the work area, such as grating, piping, and other components are removed to create sufficient laydown space for processing these large components.

The generators are rigged for removal, disconnected from the surrounding piping and supports, and maneuvered into the open area where they are lowered onto a dolly.Each generator is rotated into the horizontal position for extraction from the containment and placed onto a multi-wheeled vehicle for transport to an on-site processing and storage area.The generators are disassembled on-site with the steam dome and lightly contaminated subassemblies designated for off-site recycling.

The more highly contaminated tube sheet and tube bundle are packaged for direct disposal.The interior volume is filled with low-density cellular concrete for stabilization of the internal contamination.

Reactor coolant piping is cut from the reactor vessel once the water level in the vessel (used for personnel shielthng during dismantling and cutting operations in and around the vessel)is dropped below the nozzle zone.The piping is boxed and transported by shielded van.The reactor coolant pumps and motors are lifted out intact, packaged, and transported for processing and/or disposal.TLG Services, Inc.

ULNRC-06349 Page 47 of 173 Cafluway Energy Center Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 10 of 30 3.4.4 Retired Components The estimate includes the cost to dispose of four retired steam generators expected to be in storage at the site upon the cessation of plant operations.

The components are processed for disposal in the same manner as described for the installed units.A retired reactor closure head, with service structure, is also included in the decommissioning waste inventory.

The component is currently stored in the steam generator storage facility.3.4.5 Main Turbine and Condenser The main turbine is dismantled using conventional maintenance procedures.

The turbine rotors and shafts are removed to a laydown area.The lower turbine casings are removed from their anchors by controlled demolition.

The main condensers are also disassembled and moved to a laydown area.Material is then prepared for transportation to an off-site recycling facility where it is surveyed and designated for either decontamination or volume reduction, conventional disposal, or controlled disposal.Components are packaged and readied for transport in accordance with the intended disposition.

3.4.6 Transportation

Methods Contaminated piping, components, and structural material other than the highly activated reactor vessel and internal components will qualify as L$A-I, II or III or Surface Contaminated Object,$CO-I or II, as described in Title 49,[21]The contaminated material will be packaged in Industrial Packages (IP-1, IP-2, or IP-3, as defined in subpart 173.411)for transport unless demonstrated to qualify as their own shipping containers.

The reactor vessel and internal components are expected to be transported in accordance with Part 71, as Type B.It is conceivable that the reactor, due to its limited specific activity, could qualify as LSA II or III.However, the high radiation levels on the outer surface would require that additional shielding be incorporated within the packaging so as to attenuate the dose to levels acceptable for transport.

Any fuel cladding failure that occurred during the lifetime of the plant is assumed to have released fission products at sufficiently low levels that the buildup of quantities of long-lived isotopes (e.g.,'7Cs, 905r, or transuranics) has been prevented from reaching levels exceeding those TLG Services, Inc.

ULNRC-06349 Page 48 of 173 Caflaway Energy Center.Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 11 of 30 that permit the major reactor components to be shipped under current transportation regulations and disposal requirements.

Transport of the highly activated metal, produced in the segmentation of the reactor vessel and internal components, will be by shielded truck cask.Cask shipments may exceed 95,000 pounds, including vessel segment(s), supplementary shielding, cask tie-downs, and tractor-trailer.The maximum level of activity per shipment assumed permissible was based upon the license limits of the available shielded transport casks.The segmentation scheme for the vessel and internal segments is designed to meet these limits.The transport of large intact components (e.g., large heat exchangers and other oversized components) will be by a combination of truck, rail, and/or multi-wheeled transporter.

Transportation costs for Class A radioactive material requiring controlled disposal are based upon the mileage to the Energy$olutions facility in Olive, Utah.Transportation costs for the higher activity Class B and C radioactive material are based upon the mileage to the WCS facility in Andrews County, Texas.The transportation cost for the GTCC material is assumed to be contained within the disposal cost.Transportation costs for off-site waste processing are based upon the mileage to Oak Ridge, Tennessee.

Truck transport costs were developed from published tariffs from Tn-State Motor Transit.[22]

3.4.7 Low-Level Rathoactive Waste Disposal To the greatest extent practical, metallic material generated in the decontamination and dismantling processes is processed to reduce the total cost of controlled disposal.Material meeting the regulatory andlor site release criterion, is released as scrap, requiring no further cost consideration.

Conditioning (jreparing the material to meet the waste acceptance criteria of the disposal site)and recovery of the waste stream is performed off site at a licensed processing center.Any material leaving the site is subject to a survey and release charge, at a minimum.The mass of radioactive waste generated during the various decommissioning activities at the site is shown on a line-item basis in the appendices and summarized in Section 5 (base case).The quantified waste summaries shown in these tables are consistent with 10 CFR Part 61 classifications.

Commercially available steel containers are presumed to be used for the disposal of piping, small components, and concrete.TLG Services, Inc.

ULNRC-06349 Page 49 of 173 Callaway Energy Center Document A22-1690-.OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 12 of 30 Larger components can serve as their own containers, with proper closure of all openings, access ways, and penetrations.

The volumes are calculated based on the exterior package dimensions for containerized material or a specific calculation for components serving as their own waste containers.

The more highly activated reactor components will be shipped in reusable, shielded truck casks with disposable liners.In calculating disposal costs, the burial fees are applied against the liner volume, as well as the special handling requirements of the payload.Packaging efficiencies are lower for the highly activated materials (greater than Type A quantity waste), where high concentrations of gamma-emitting rathonuclides limit the capacity of the shipping canisters.

The cost to dispose of the lowest level waste and the majority of the material generated from the decontamination and dismantling activities is based upon the current cost for disposal at Energy$olutions facility in Clive, Utah.Disposal costs for the higher activity waste (Class B and C)were based upon Ameren Missouri's current agreement with WCS for the Andrews County facility.3.4.8 Site Conditions Following Decommissioning The NRC will terminate the site license when it determines that site remediation has been performed in accordance with the license termination plan, and that the terminal radiation survey and associated documentation demonstrate that the facility is suitable for release.The NRC's involvement in the decommissioning process will end at this point.Local building codes and state environmental regulations will dictate the next step in the decommissioning process, as well as the owner's own future plans for the site.The estimates presented herein include the dismantling of the major structures to just below ground level, backfilling and the collapsing of below grade voids, and regrading such that the site upon which the power block and supplemental structures are located is transformed into a"grassy plain."The existing electrical switchyard and access roads will remain in support of the electrical transmission and distribution system.Site restoration does not include the remethation of the water treatment plant's settling basins, if required.TLG Services, Inc.

ULNRC-06349 Page 50 of 173 Caflaway Energy Center.Document A22-1690-OO1, Rev.0 Decommissioning Cost Analysis Section 3, Page 13 of 30 Sludge removed from the sewage treatment plant lagoon was assumed to contain low levels of contamination that would require controlled disposaL As such, 3,600 cubic feet of material from the lagoon was designated for disposition at Energy$olutions' facility.The existing and replacement cooling tower discharge pipes will be left in place and flow filled with suitable material to prevent the pipes from collapsing.

The intake line will also be filled.The estimates do not assume the remediation of any significant volume of contaminated soil.This assumption may be affected by continued plant operations and/or future regulatory actions, such as the development of site-specific release criteria.3.5 ASSUMPTIONS The following are the major assumptions made in the development of the estimates for decommissioning the site.3.5.1 Estimating Basis Decommissioning costs are reported in the year of projected expenditure; however, the values are provided in 2014 dollars.Costs are not inflated, escalated, or discounted over the periods of performance.

The estimates rely upon the physical plant inventory that was the basis for the 2011 analysis.The study follows the principles of ALARA through the use of work duration adjustment factors.These factors address the impact of activities such as radiological protection instruction, mock-up training, and the use of respiratory protection and protective clothing.The factors lengthen a task's duration, increasing costs and lengthening the overall schedule.ALARA planning is considered in the costs for engineering and planning, and in the development of activity specifications and detailed procedures.

Changes to worker exposure limits may impact the decommissioning cost and project schedule.3.5.2 Labor Costs Ameren Missouri, as the operator, will continue to provide site operations support, incluthng decommissioning program management, licensing, radiological protection, and site security.A Decommissioning TLG Services, Inc.