ML032340563

Draft Revision 2 to Ice Condenser Utility Group Topical Report No. ICUG-001: Application of the Active Ice Mass Management Concept to the Ice Condenser Ice Mass Technical Specification

ML032340563
Person / Time
Site:	Catawba, McGuire, Mcguire
Issue date:	05/29/2003
From:	Lytton R Duke Power Co
To:	Martin R Office of Nuclear Reactor Regulation
References
TAC MB3379
Download: ML032340563 (16)

Text

I I It i- ~duke Duke Power e Power. t'V~~~~~~~~~ower. ~~~~~~~~~~~~Energy P.O. BoxCenter 1006 A Dusk EdW Compeg Charlote, NC 28201-1006 May29, 2003:-

- . .S.Nuclear Regulatory Commission Washi-gtoD. C. 20555-0001 Attention: R Martin (addressee only)

Subject:

Drad(evision 2 to Ice Condenser Utility Group Topical Report No. ICUG-001:

Apphi.ation of the Active Ice Mass Management Concept to the Ice Condenser Ice Mass Technical Specification (TAC No. MB3379)

Gentlemen:

Please find enclosed a draft of Revision 2 to non-proprietary topical report ICUG-001, "Application of the Active Ice Mass Management Concept to the Ice Condenser Ice Mass Technical Specification." This revision is submitted by the Ice Condenser Utility Group (ICUG) to NRC in response to the staffs draft Safety Evaluation Report (SER) for Revision 0 of the ICUG-001 topical report dated May 6, 2003, and also to commitments made at the May 13, 2003 ICUG/NRC meeting.

The enclosed draft revision 2 to the topical report resolves several issues identified in the draft SER and discussed at the 5/13/03 meeting. Upon staff review and acceptance of the changes presented in this draft, a formal Revision 2 to the ICUG-001 topical report will be issued.

If there are any questions or if additional information is needed, please contact the undersigned at (704) 382-3970 or rslyttonduke-energy.com.

Sincerely, R. S. Lytton Chair, Ice Condenser Utility Group Enclosure xc(w/enclosure): Robert E. Martin (addressee only, 10 copies)

Document Control Desk (one copy)

Ice Condenser Utility Group Applicationof the Active Ice Mass Management Concept to the Ice Condenser Ice Mass Technical Specification Topical Report ICUG-001, Revision 2 May 2003 D RAFT NON-PROPRIETARY

The information contained in this topical report is considered non-proprietary. As the sole property of the Ice Condenser Utility Group, revision to It In whole or in part or reproduction for the purpose of general distribution is not permitted without the express written consent of ICUG.

Signatures below indicate Licensee endorsement of the technical concepts presented herein.

Ice CondenserUtility Group Representatives Russ Lytton Duke Energy Corporation, Nuclear Engineering-Chair Bob Fulbright Duke Energy Corporation, McGuire Nuclear Station Engineering Bobby Lamb Duke Energy Corporation, McGuire Nuclear Station Maintenance Mike Wilder Duke Energy Corporation, McGuire Nuclear Station Licensing Joe McKeown Duke Energy Corporation, Catawba Nuclear Station Engineering Charlie Kelly Duke Energy Corporation, Catawba Nuclear Station Maintenance For Catawba / McGuire Nuclear Stations:

Jennifer Regan Tennessee Valley Authority, Sequoyah Nuclear Plant Engineering Bob Ives Tennessee Valley Authority, Sequoyah Nuclear Plant Maintenance Jan Bajraszewski Tennessee Valley Authority, Sequoyah Nuclear Plant Ucensing For Sequoyah Nuclear Plant:

Phil Smith Tennessee Valley Authority, Watts Bar Nuclear Plant Engineering Gary Jordan Tennessee Valley Authority, Watts Bar Nuclear Plant Engineering Paul Pace Tennessee Valley Authority, Watts Bar Nuclear Plant Licensing For Watts Bar Nuclear Plant:

Brenda Kovarik American Electric Power Company, D.C. Cook Nuclear Plant Engineering Paul Leonard American Electric Power Company, D.C. Cook Nuclear Plant Engineering For Donald C. Cook Nuclear Plant:

Ice Condenser Executive Steerina Team Renresentatives H. B. Barron, Jr. Duke Energy Corp., Site Vice President, McGuire Nuclear Station-Chair G. R. Peterson Duke Energy Corp., Site Vice President, Catawba Nuclear Station R. T. Purcell Tennessee Valley Authority, Site Vice President, Sequoyah Nuclear Plant J. E. Maddox Tennessee Valley Authority, Engineering Manager, Watts Bar Nuclear Plant M. W. Rencheck American Electric Power Co., Vice President-Engineering, D.C. Cook Nuclear Plant Additional assistance provided by MPR Associates, Inc.

TOPICAL REPORT ICUG-OO1, Revision 2 i May 2003 DRAFT

Topical Report ICUG-001 Application of the Active Ice Mass Management Concept to the Ice CondenserIce Mass Technical Specification Table of Contents

> Overview 0-1

• Active Ice Mass Management

• Industry Challenges

• Summary of Signifcant Aspects

• Applicability to Ice Condenser Plants

> 1: Ice Mass Requirement Design Basis and Industry Data 1-1

• Purpose/Scope

• Design Basis

• Original Ice Mass Technical Specification Requirements

• Historical Data

• Historical Data Analysis

• AIMM Methodology

- Determination of Ice Basket Mass InAIMM Practice

• The Radial Zone Concept

• Regions of Localized Degraded Mass

• Conclusions

> II: Ice Basket Mass Determination MethodoloMv 11-i

• Purpose/Scope

• Discussion

- Preferred Ice Mass Determination Method

- Alternate Ice Mass Determination Methods

• Standards: Ice Basket Mass Determination Uncertainty

- Concepts Regarding Uncertainty

- Error

- Precision of Instrument Readings and Raw Data

- Quantifying Measurement Uncertainty

- Historical data Validity - Altemate Ice Mass Determination Methods

- Examples

- Example Summary

• Conclusions

> III: Ice Mass Statistical Sampling Plan m-l

• Purpose/Scope

• Ice Mass Statistical Strategy

- Sample Size

- Stratified Sampling

- Alternate Mass Determination Methods

- Alftemate Basket Selection Strategy

• Applications of Sampling Plan

• Summary

> References R-1 9 Appendix A A-1 TOPICAL REPORT ICUG-001, Revision 2 ii May 2003 DRtAFT

Topical Report ICUG-001 Applicaton of the Active Ice Mass Management Concept to the Ice Condenser ke Mass TechnicalSpecification List of Figures and Tables Figures

• Figure 0-1. Ice Mass Surveillance Strategy 0-4

• Figure 1-1. Typical Plan View of Containment Building 1-3

• Figure 1-2. Row-Group Sublimation Rates 1-5

• Figure 1-3. Radial Row Sublimation Rates 1-7

• Figure 1.4. Radial Zone Sublimation Rates 1-8

• Figure 2-1. Projection Method Example Chart 1-9

• Figure 2-2. Visual Estimation Method Example Chart li

• Figure 3-1. Illustration of Student's t-Test m-1

• Figure 3-2. Effect of Sample Size on the Error of the Mean rn-4

• Figure 3-3. Illustrative Plan View of Ice Bed, Showing Three Radial Zone Groupings of Ice Baskets (648 baskets each) rn-s

• Figure 3-4. Plan View of Containment Building, Showing Proximity of Steam Generator and Pressurizer Compartments to Ice Condenser Bays III-6

• Figure 3-5. Effect of Visual Estimation Measurement Error on the Error of the Mean for Various Sample Sizes III-10

• Figure A-1. Typical Bay Arrangement and Identification A-2

• Figure A-2. Typical Bay Map and Basket IdentificatIon A-3 Tables

• Table 0-1. Significant Aspects of the Ice Mass Technical Specification 0-5 Methodology

• Table 1-1. Row-Group Sublimation Rates I-S

• Table 1-2. Radial Row Sublimation Rates I-6

• Table 1-3. Radial Zone Sublimation Rates 1-8

• Table 2-1. Alternate Mass Determination Technique Data Refreshment Criteria 11-7

• Table 2-2. Projection Method Example Data II-8

• Table 2-3. Visual Estimation Method Example Data 1I-11

• Table 3-1. Ice Basket Mass Measurement Random Error -I-7

• Table 3-2. Illustration of Effects of Alternate Mass Determination Methods And Expanded Sample - Radial Zone A mn-8

• Table 3-3. Ice Bed Masses from Sample Group rn-il

• Table 3-4. Ice Mass Sample Group m-12

• Table 3-5. Ice Mass Sampling Plan Recommendations rn-1s

• Table A-1. Example Ice Bed Data - For Reference Only A-4

• Table A-2. Ice Mass Sample Group A-43

• Table A-3. Example Calculations A-47 TOPICAL REPORT ICUG-001, Revision 2 iii May 2003 DRAFT

Topical Report ICUG-001 Application of the Active Ice Mass Management Concept to the Ice Condenser Ice Mass Technical Specification Nomenclature This topical report will utilize terminology that describes aspects of the supported technical specification methodology. In the interest of consistency, the following definitions apply to terms used throughout the report:

• Radial: Direction along a line drawn from the center of containment toward the outer containment wall.

• Azimuthal: Direction along a circular line drawn from ice condenser Bay I towards Bay 24, or vice-versa.

• Row: Linear population of ice baskets in the azimuthal direction; there are 216 baskets per row in an ice bed, with nine rows total.

• Column: Linear population of ice baskets in the radial direction; there are nine baskets per column and nine columns in a bay, with 216 columns total.

• Accuracy: Generic term referring to the ability of a methodology to assess the mass of an ice basket.

• Error: Statistical term referring to the numerical difference between an actual ice basket mass and its measured mass.

• Random sample: A sample of ice baskets selected from the parent population of ice baskets in an ice bed, where each basket in the parent population has the same probability of being selected.

• Stratfled random sample: A sample of ice baskets selected from a defined sub-population of ice baskets, where each basket in the sub-population has the same probability of being selected.

• Representaesample: A sample of ice baskets intentionally selected from specified areas of the ice bed population, such that all areas are equally represented.

• Ice mass: The total mass of ice that exists in a population of individual ice baskets, without the baskets themselves included (i.e., no tare weights).

• RadialZone: A defined population of ice baskets encompassing all ice baskets in a given row or rows.

• Bay-Zone: A population of ice baskets in a Radial Zone delimited by a given Bay.

• Ice bed: The entire population of ice baskets, ice, and supporting structures in the ice condenser from the Lower Support Structure up to, but not including, the Intermediate Deck, End Walls, and Wall Panels.

• Stuck basket: An ice basket that is prevented from being physically lifted, due to either freezing (to the lattice structure) or mechanical impediment.

• Obstructedbasket: An ice basket that, due to excessive external surface ice or other blockage, cannot be inspected along its height.

TOPICAL REPORT ICUG-001, Revision 2 iv May 2003 DRAFT

• AlternateMass Determination Technique: Any methodology employed to assess the mass of an individual ice basket other than physically lifting the ice basket.

• Inia sample: A set of ice baskets chosen at random from a given Radial Zone as a part of the initial sample grouping for the Ice Mass Technical Specification surveillance requirement.

• Expandedsample: An additional set of sample baskets chosen at random from a given Radial Zone, with the initial sample set removed from the population.

• Alternate basket: An ice basket chosen to replace the initial sample basket, when the initial sample basket is stuck and obstructed.

• Mean: The average of a set of ice basket masses.

• 95% level of confidence (or confidence interval): 95% confidence refers to an interval (x lb toy lb, or x lb or greater) which is calculated based on the number of samples, sample mean, sample standard deviation, and the confidence level (95% in this case), that aims to predict the actual mean for the entire population. The interval envelopes the actual mean of the parent population 95% of the time. Of all possible sample groups that could be chosen from the parent population, 95% of them would result in an interval that contains the actual mean ice basket mass for the parent population.

• Student's t-test: Statistical procedure used to determine the parent population mean from the mean of a sample group at a prescribed confidence interval.

• Errorofthe mean: Statistical term that designates the difference between the mean of a sample group and the mean of the parent population at a prescribed confidence interval.

• Random error:A deviation from the actual value which occurs in a non-systematic manner.

• Variation oftheprocess: Statistical term that refers to the variation of the actual mass of the baskets throughout the ice bed.

• Variationofthe measurement Statistical term that refers to the variation of the measured mass of an ice basket due to variations in the measurement technique.

• Normality: The degree to which the sample distribution has the attributes of a normal distribution.

• Sampling without replacement.Taking samples from a parent population wherein each basket in the population can appear only once in the sample. Once a basket is selected from the parent population, it is removed from the candidate population of baskets for the next selection and therefore, it may not be selected again for the sample.

TOPICAL REPORT ICUG-001, Revision 2 v May 2003 DRAFT

Overview The Ice Condenser Utility Group (ICUG), consisting of members of all domestic ice condenser-owning utilities (Tennessee Valley Authority, American Electric Power, and Duke Energy), has collectively amassed nearly 150 years of operational experience in the ice condenser since D.C. Cook Nuclear Plant Unit 1began commercial operation in 1975. Since then, eight more ice condenser containments have been added to the fleet, all of which are currently operational. The original technical specification verifying total ice mass and distribution in the ice bed has been extensively reviewed by both the NRC and ICUG.

While it is considered adequate to show operability, some concepts from which the original specification was derived have changed, and others need clarification. Several potential changes to the specification have been identified that allow the application of the industry's accumulated operational history and experience, as well as provide an improved process for verifying total ice mass. This topical report will address those improvements to the Ice Mass Technical Specification and show the inherent linkage to plant-specific maintenance practices.

Active Ice Mass Management As operational history shows, sublimation rates are quite significant in certain areas of the ice condenser and essentially non-existent in others, and a large effort is required to maintain the ice bed mass inventory each outage. This maintenance effort, however, restores the ice bed mass and distribution characteristics required for continued operation. The process of replenishing the ice baskets to restore ice bed mass based on the monitoring of varying sublimation rates during the cycle is the basis for the Active Ice Mass Management (AIMM) concept.

This concept is rooted in the industry's adherence to the IOCFR50 Appendix B requirements governing maintenance to a nuclear safety-related system. Existing ARMM practices manage each ice basket in the ice bed above the required mean mass supporting the safety analysis. It is a natural follow-on, then, to revise and maintain the technical specification to accommodate AIMM methodology and at the same time introduce industry operational experience. For example, the original specification describes an "as-left" (post-maintenance) surveillance of total mass and distribution, which requires that an assumed uniform sublimation (and weighing error) allowance be included in the surveillance limit. In this manner, ice mass is shown to be adequate for the coming operational cycle. The new approach uses an "as-found" (pre-maintenance) surveillance. This improvement accomplishes several things:

> An as-found surveillance shows the adequacy of total ice mass for the current operational cycle. The total mass surveillance limit is the actual minimum requirement for ice bed operability.

> The sublimation allowance and mass determination accuracy details become plant-specific procedural entities (allowing them to vary), which is more precise than assuming a uniform sublimation rate across the ice bed.

> The performance of an as-found surveillance inherently verifies the propriety of a plant's Active Ice Mass Management process, since compliance with the technical specification shows awareness of varied ice bed sublimation rates.

> Radial zones in the ice bed can be defined for statistical purposes that delineate groups of ice baskets with similar expected as-found mean mass and a reasonable standard deviation. With AIMM methodology ensuring replenishment of needed mass, these zones facilitate an accurate assessment of total ice bed inventory.

The result is a technical specification that appropriately combines accumulated experience, knowledge of the ice condenser design basis, and the use of statistical methods to support an industry-consistent, simplified surveillance and, in turn, enhanced Unit reliability. In this regard, while the concept of a consistent technical specification surveillance is an important industry objective, plant-specific TOPICAL REPORT ICUG-001, Revision 2 0-1 May 2003 DRAFT

maintenance techniques used in implementing AIMM methodology must necessarily be allowed to evolve independently. These techniques are constantly being improved at each plant, and the exchange of technical information facilitated through the ICUG ensures industry peer review. Primarily, it is the Ice Mass Technical Specification itself that must be consistent in its intent and application.

IndustryChallenaes The design of the ice condenser system constantly challenges industry initiative, given that operational experience has rewritten some of the original assumptions regarding ice bed behavior. While the ice condenser itself appears passive, sublimation, frost build-up, and a saturated environment all take their toll over the course of an operational cycle. Ice bed maintenance processes contribute further; the use of vibrators and thermal drills to replenish sublimated ice baskets creates an outfall of ice/water, which, while expected, tends to make other maintenance-related activities more time-consuming.

Among the most significant challenges faced by the industry in verifying total ice mass are frozen (or "stuck") ice baskets. The situation occurs when external basket surfaces become covered with ice and frost and effectively freezes them to the lattice structure, rendering some baskets incapable of being physically lifted unless a significant amount of force is used. Stuck baskets also occur when support steel or some other mechanical impediment hinders vertical basket movement. This prevents the use of a lifting rig to determine mass, which is the method of choice by the industry since it is relatively fast and the most accurate. The limitation that results has necessitated the selection of representative alternate baskets for the statistical sample, the use of which over time has been implemented differently by individual plants due (in part) to vague original guidance provided. This has created interpretation inconsistencies across the industry. Compounding the issue is the knowledge that all ice baskets that require servicing are replenished during ice bed outage maintenance, but not all can be used to verify the total ice mass: some baskets' mass cannot be ascertained by lifting (stuck) and others were excluded from'the sample group by design. The industry realized that a basket that has been just replenished, but is stuck, does not constitute a threat to the design basis of the ice condenser. Likewise, a recently replenished basket that resides in a historically low sublimation region of the ice bed, but is stuck, does not constitute a threat. In the larger view, no basket-stuck or otherwise-is a threat to ice bed operability unless the amount of ice in it (or lack thereof) is indicative of a localized area of degraded ice bed mass or contributes to the surveillance requirement for total mass not being met.

The technical specification approach supported by this topical report resolves this by introducing alternate mass determination techniques for ice baskets that cannot be physically lifted. These techniques-the detailed development of which are plant-specific--currently have been designed to utilize both existing historical information (such as in the use of trending software for basket mass projections) and visual profiling/estimation. The methods are valid forms of ice basket mass determination as long as the accuracy of the methods is properly accounted for in both the actual measurement and the statistical sampling plan.

In this respect, it is also recognized that even with alternate mass determination methodology defined, there will be occasions when no currently available technique can ascertain the mass of ice in some baskets, due to a physical obstruction or other situation (such as external frost/ice build-up on a historically stuck basket that prevents visual inspection). As also allowed in previous versions of the technical specification, in these cases an alternate sample basket from the vicinity of the initial sample will need to be selected and therefore guidelines adopted. To accomplish this, the alternate selection criteria have been designed around the Radial Zone concept, in which baskets in the same Radial Zone generally have similar mass. Alternate selections are representative of initial selections as long as they have the same probability of being selected as an initial selection and can be expected to have similar characteristics as an initial selection. Limiting an alternate selection to the same Bay as the obstructed original selection further develops the criterion, and allows inclusion of baskets from previously excluded TOPICAL REPORT ICUG-001, Revision 2 0-2 May 2003 DRAFT

rows: all ice baskets in the ice bed are included in the sampling plan while the original version exempted 33% (radial rows 3, 5, and 7) of the ice bed from the parent population. In addition, the use of alternate selections is restricted to prevent repeated use of the same alternate basket from affecting statistical confidence.

A further disparity in the historical methodology required each statistically sampled basket to contain the specified amount of ice, while the Bases allowed for individual baskets to be "light" (i.e., less than the technical specification required minimum mass) if baskets in the local area were sufficiently full. This contradiction also led to differing industry interpretations, even though the original intent was, as described by the technical specification bases, to prevent localized gross degradation of the ice bed. The technical specification methodology presented here treats this contradiction by recognizing that the two primary concerns of the ice mass design basis-and therefore the two required surveillances-are the presence of sufficient total ice mass in the bed distributed appropriately to accommodate the overall DBA response, and a sufficient minimum mass in any individual basket maintained to prevent localized areas of degradation that might challenge the DBA containment pressure response.

The requirement for the overall DBA response is met by determining total ice mass in the bed based on a sampled group. In this manner, the word "each" is eliminated from the operability requirement, and individual baskets can sublimate during an operating cycle to whatever level their relative position in the ice bed dictates. Conversely, the minimum individual basket mass requirement stipulates a minimum mass of ice for each of the statistically sampled baskets so that a minimum amount of ice in the basket is verified to be present. The use of each in this instance is appropriate, since the containment analysis is primarily concerned with localized degradation (i.e., a cluster of baskets with degraded mass) and the sampled group is a valid representation of the entire Radial Zone under surveillance. As noted previously, AIMM practice will manage each basket above the required safety analysis mean, such that no individual basket would be expected to sublimate below this mean value. If a basket sublimates below the safety analysis mean value this instance is identified within the plant's corrective action program, including evaluating AJMM practices to identify the cause and to correct any deficiencies. If a basket sublimates below the minimum individual basket mass requirement, then this condition is TS prohibited, necessitating reporting per the requirements of 10CFR50.73 in addition to corrective action program determination of cause and appropriate corrective actions. Certain individual baskets in the corners of the ice bed would typically pose the greatest challenge to maintaining their stored ice mass above the safety analysis mean, due to the relatively high sublimation rates in these areas. However, AIMM practice would generally identify these baskets for servicing every outage, thereby enabling the ice mass in these baskets to be maintained above the safety analysis mean, which would prevent any challenge to the surveillance requirements.

Summary of Significant Aspects The approach to the Ice Mass Technical Specification supported by this topical report is in some ways similar to the original, but in others, very different. The subdivision of the ice bed into Radial Zones for the purpose of sampling, each comprising a third of the ice baskets in the bed, recognizes that the original representativesample did much the same thing by defining the sampled radial rows to be 1, 2, 4, 6, 8, and 9, which essentially outlined three regions of generally similar characteristics. Industry commitments to manage the ice mass in each basket above the required safety analysis mean, a statistically random sample in each Radial Zone, and a defined minimum individual ice mass per basket combine to become the basis for verification of appropriate ice distribution in lieu of a limited azimuthal row-group surveillance. The addition of alternate mass determination techniques for individual baskets and a more restrictive (same Radial Zone, same Bay) procedure for utilizing alternate baskets when original samples are stuck and obstructed clarify two areas of inherent weakness in the original surveillance. These and other enhancements provide a much improved surveillance that is simpler and more clearly defined than the original.

TOPICAL REPORT ICUG-001, Revision 2 0-3 May 2003 DRAFT

basis of this technical the forming strategies 0-1 charts the Figure Figure 0-1 charts the strategies forming the basis of this technical specification methodology for verification of ice mass.

Figure 0-1. Ice Mass Surveillance Strategy TOPICAL REPORT ICUG-001, Revision 2 0-4 May 2003 DRAFT

Table 0-1 identifies the most significant aspects of the technical specification methodology supported by this topical report Table 0-1.-Significant Aspects of the Ice Mass Technical Specification Methodology

• The surveillances used to ascertain ice mass and distribution are performed in the as-found (pre-maintenance) condition, as opposed to the as-left (post-maintenance) condition o The minimum operability requirements for total ice mass are defined to better reflect the design basis o Sublimation allowances and mass determination accuracy are accommodated by plant-specific maintenance procedures o A surveillance for minimum total ice mass in the bed assures the initial conditions of the DBA analyses a A surveillance for minimum ice mass in each individual basket prevents localized degradation to avoid any challenge to the DBA containment pressure response a For the purpose of statistical analysis, the ice bed is divided into three Radial Zones of three sequential rows each to isolate basket populations that have similar mass characteristics o Proper azimuthal distribution of ice in the ice bed is no longer assessed by a separate surveillance requirement; it is implemented through established industry-wide maintenance practices that manage each ice basket above the required safety analysis mean and confirmed through as-found random sampling techniques o All ice baskets in the parent population are sulbject to random statistical sampling, as opposed to only two-thirds of the population subject to representative sampling o Methods of determining the mass of individual sample baskets other than manual lifting are allowed a The process for selecting an alternate basket for the statistical sample when the mass ofan initial sample basket cannot be ascertained by any method has been revised, restricting alternates to those baskets in the same Radial Zone, same Bay as the initial sample and limiting their re-use as an alternate from prior surveillances Applicabilltv to Ice Condenser Plants The generic industry position developed and presented in this topical report utilizes historical operational information and data obtained from Tennessee Valley Authority's Sequoyah and Watts Bar Nuclear Plants, and Duke Energy Corporation's McGuire and Catawba Nuclear Stations. Specific historical ice bed data from D.C. Cook Nuclear Plant was not included due to past configuration control and consistency issues that have since been resolved. Generic data and trends from the Cook plant, however, are consistent with the remainder of the industry and as such were included in assessing the industry position presented herein.

The concept of Radial Zones was developed by the industry based on collective historical sublimation data and the need for a more accurate assessment of ice bed mass as it relates to containment safety analyses and active maintenance practices. Currently, the Design Basis Accident (DBA) containment response model for the short-term blowdown phase for all ice condenser plants is based on Westinghouse Electric Company's Transient Mass Distribution (TMD) code. With the exception of the Duke plants, which utilize a previously approved GOTHIC model, the long-term phase of the DBA is modeled by Westinghouse's Long Term Ice Condenser (LOTIC) codes. With this foundation, all industry plants can adopt the Radial Zone concept-and the ice mass derived therefrom-for the basis of their ice mass technical specification. While this topical report describes the industry-standard Radial Zone TOPICAL REPORT ICUG-001, Revision 2 0-5 May 2003 DRAFT

configuration (three Radial Zones containing three sequential rows of ice baskets each), it is noted that more refined configurations are possible using similar technical justification. Any Radial Zone configuration different than the industry standard, however, is subject to the same statistical sampling plan and alternate selection criteria described herein.

TOPICAL REPORT ICUG-001, Revision 2 0-6 May 2003 DRAFT

Ice Mass Requirement Design Basis and Industry Data Purpose / Scone The purpose of this Section is to describe the historical development of the ice mass requirement design basis and provide the link to the Ice Mass Technical Specification and ARMM methodologies. Analysis of historical operational data is performed to support the approach.

Historical sublimation data from Duke Energy's McGuire and Catawba Nuclear Stations and Tennessee Valley Authority's Sequoyah and Watts Bar Nuclear Plants was compiled and normalized to reflect a typical ice condenser plant. The normalized data from these seven units of record is generally indicative of any domestic ice condenser, including the two at D.C. Cook Nuclear Plant. Concepts introduced in this Section are based on current industry practice, sublimation rate analyses, design basis interpretation, and operating experience.

Design Basis The ice condenser containment is analyzed for the limiting design basis accident (ie., a double-ended guillotine reactor coolant pipe break loss-of-coolant accident, or large-break LOCA) for confirmation of pressurization integrity in accordance with 10CFR50, Appendix A General Design Criterion 50. The containment is analyzed for both short-tern and long-term pressurization effects.

The short-term containment pressurization analysis is performed using the Westinghouse Transient Mass Distribution (IMD) analysis code. The short-term analysis, whose actual duration is a function of plant specific parameters but is modeled as a ten-second event, establishes the peak pressure differential across the ice condenser and reactor building structures that separate lower containment from upper containment.

The analysis confirms the ice condenser and related structures will maintain their structural integrity under peak differential pressure loads caused by the compression of the lower containment air volume as it is forced into upper containment through the ice condenser as a result of the mass and energy released in the initial seconds of a large-break LOCA. The short-term containment integrity analysis assumes a fixed flow area through the ice condenser, which establishes the design basis requirement for ice condenser flow passage area. Westinghouse Electric Corporation tested the capability of the ice bed to withstand the blowdown energy release at their Waltz Mill Facility and documented the results for each plant (Ref. 14-18).

The long-term containment pressurization analysis is performed using the two-dimensional Westinghouse Long Term Ice Condenser Containment (LOTIC) analysis code (the three-dimensional GOTHIC analysis code is used for the Duke plants). The long-term analysis evaluates containment pressurization beginning with reactor coolant system blowdown, and continues through ice bed melt-out and subsequent containment building pressurization control using the containment spray and residual heat removal systems. The analysis is used to confirn that the peak containment pressure remains below the design limit at all times following a large-break LOCA. The long-term analysis assumes an initial ice mass in the ice condenser that suppresses containment pressurization as the ice bed melts. At the time that sections of the ice bed begin to completely melt out, the emergency core cooling systems are realigned from the refueling water storage tank to the containment recirculation sump. Following complete ice bed melt-out of all sections, containment spray systems and injection systems suppress containment pressurization with active heat removal being provided by emergency core cooling heat exchanger(s). The assumed ice mass in the LOTIC/GOTHIC analyses must be sufficient to limit the peak containment pressure below the design basis limit following ice bed melt-out, and typically also delay melt-out of complete sections of the TOPICAL REPORT ICUG-001, Revision 2 1-1 May 2003 DRAFT

ice bed until emergency core cooling systems are aligned to the containment sump. One of the fundamental assumptions of the two-dimensional LOTIC model is that only a minimal amount of the mass and energy released in the lower containment bypasses the ice condenser until the time of ice bed melt-out of complete sections. While it is understood that the ice bed will not likely melt out evenly over the course of the DBA, early melt-through of sections of the ice condenser could reduce the modeled efficiency of the ice condenser, resulting in increased containment pressurization. Early melt-through of the ice bed will not occur as long as 1) the ice condenser and related structures maintain their structural integrity (as demonstrated by the short-term TMD containment analysis), and 2) enough ice mass is sufficiently distributed such that localized degraded regions of mass do not exist in the ice bed. In this manner, the LOTIC/GOTHIC analyses assumptions and methodology establish the design basis requirements for total ice mass.

Historically, an as-left ice mass surveillance was used to verify that the design basis parameters would be met throughout the coming fuel cycle. The as-left Technical Specification ice mass requirement contained an added sublimation allowance for anticipated ice loss through the cycle, and an additional conservative allowance to account for mass determination uncertainty.

Oriinal Ice Mass Technical Specfcation Requirements Based on historical industry experience (references 1 and 2), a 144-basket sample size resulted from two separate increases. D.C. Cook Nuclear Plant Unit I was the first ice condenser containment to operate, and ice mass was closely monitored. For two years in the mid-1970s, ice mass was obtained and analyzed at three- or four-month intervals (references 3 - 7). The first ice mass Technical Specification, supplied by Westinghouse Electric Corporation as an experimental version, required that a total of 60 ice baskets be weighed from the ice bed parent population. After the initial evaluation program was complete in 1975, ice bed sublimation patterns were recognized as significant; the sample size was increased from 60.

to 96 and created a representativesample, with one basket each taken from radial rows 2, 4, 6, and 8 in each of the 24 bays. Then, in 1976, technological advances allowed the inner and outer radial rows (rows 1 and 9) to be lifted, which resulted in additional ice mass data collection. Evaluation of the data indicated that the most active sublimation occurred in these two radial rows. The technical specification was again revised in 1977, increasing the sample size from 96 to 144 ice baskets to add samples from the two outer radial rows. The 144-basket sample configuration was considered representative of the parent population and included six baskets from each of the 24 ice condenser bays, consisting of one basket from each of radial rows 1, 2, 4, 6, 8, and 9 per bay.

This representative sample was used to calculate the total ice bed mass with a 95% level of confidence, as determined by ensuring that each individual basket mass in the sample group was in compliance with the surveillance requirement's per-basket limit. The individual sample basket masses were also used to ensure the azimuthal distribution of ice was reasonably uniform. This was accomplished by subdividing the ice bed into Row-Groups, and ensuring the limit per basket for each was met. The Groups were defined as follows:

Group 1 - bays 1 through 8 Group 2 - bays 9 through 16 Group 3 - bays 17 through 24 These groups align with the location of the Steam Generator compartments, the Pressurizer compartment, and the Reactor Coolant Pumps as shown in Figure 1-1. The groups are also consistent with the sectored initial ice loading strategy employed by the D.C. Cook plant in 1974.

TOPICAL REPORT ICUG-001, Revision 2 1-2 May 2003 DRAFT

Figure 1-1. Typical Plan View of Containment Building As noted previously, the original ice mass technical specification required individual sampled basket masses meet the surveillance requirement limit in order to verify total mass. In addition, these masses were used as the verification that a degraded localized region did not exist in the ice bed that would challenge the DBA pressure response. If a basket in the 144-basket statistical sample was found to weigh less than the required individual limit (described as "light"), the sample was to be increased in the localized region (i.e., the affected Bay) by 20 baskets. The averaged mass of the 20 additional baskets and the "light" basket was then required to meet the surveillance limit.

HistoricalData In the effort to revise the original Ice Mass Technical Specification, the industry agreed to evaluate historical data to develop a surveillance that is consistent with evolved maintenance techniques and operating experience. Since most domestic ice condenser plants have implemented the use of the trending software ICEMANTm, which was developed by Duke Energy Corporation and Framatome ANP, it will be used to compile historical industry data.

TOPICAL REPORT ICUG-001, Revision 2 1-3 May 2003 DRAFT

The ICEMANNm program is an ICE condenser MANagement system that provides for scheduling and managing ice condenser maintenance activities such as ice mass determination, ice basket replenishing, basket maintenance, and flow channel inspection and cleaning. It also provides technical specification analysis methodology and specific reports required by maintenance procedures, regulations, and administration. ICEMANTm maintains a record of each basket's historical "life", which aids in active management of the ice bed mass.

For this development, historical ice basket sublimation data was taken from each plant's ICEMANTM database and averaged to represent typical ice basket sublimation rates. This was accomplished by first defining valid data from each unit's database. Valid ice basket mass data, for the purposes of analysis, is considered to be individual baskets having more than 1,400 recent consecutive days (about three cycles) of sublimation information. These criteria ensure that cycle-to-cycle variances are not dominant and the effects of AIMM practice are included. Then, ice baskets with valid data were combined into a single database, providing each basket with as many as seven sublimation rate entries (one for each ice condenser unit of record). Sublimation rates were then averaged resulting in one data set containing 1,944 ice baskets, each with an associated industry mean basket sublimation rate. For clarity, ice baskets that have only one entry were assumed to be the industry average.

Historical Data Analysis Historical technical specification data (which excluded baskets in radial rows 3, 5, and 7 from the sample group) was used as the basis for a normal operating cycle sublimation analysis, since industry data for these rows is the most complete. Industry mean basket sublimation rates were applied to the previously defined Row-Groups, and the Row-Group mean sublimation rates and associated standard deviation from a population of 72 baskets per group calculated. Table 1-1 shows a comparison of the mean sublimation rates for each Row-Group and each radial row, where row 9 represents the row adjacent to the inner Crane Wall and row 1, the outer Containment Wall. The mean radial row sublimation rates shown in Table 1-1 are based on a row population of 216 baskets. Figure 1-2 is a graphical representation of the same data.

Table 1-1. Row-Group Sublimation Rates Radial Mean Sublimation Rate Standard Deviation Row (lb/l8month) (Ib/i8 month) 9 Row 153 - 56 Group I 176 42 Group 2 102 36 Group 3 181 51

. Row -97 22 Group I 107 19 iGrsup 2 76 12 Group3 107 14 6 - Row o 38 10 C2w= I 41 11 Group 2 0 ~0 35 7 2Mp3 38 Ii 4 - Row- 16 12 Group 1 17 12 EGrotup2 14 4 Group3 17 16 2 Row 11 25 14 25 up 2_

Gro,, 4 7 Croup 3 15 33 L Row 16 30 25 35

___ 2 _=

_Group 6 13

_ 7 Group3 16 34 TOPICAL REPORT ICUG-001, Revision 2 14 May 2003 DRAFT

Figure 1-2. Row-Group Sublimation Rates 200 180 160 140 120

_Group 1

_Group 2 100 iGroup 3

-*-Row Avg.

80 60 40 20 0

Row 9 Row 8 Row 6 Row 4 Row 2 Row I As shown in Table 1-1 and Figure 1-2, historical industry sublimation data indicates effects in both the radial and the azimuthal directions across the bed, an expected behavior primarily due to the proximity of heat sources in Containment. While the end wall bays (bays 1 and 24) and Groups immediately adjacent to the Steam Generator and Pressurizer compartments (Groups 1 and 3) show some azimuthal variance, these groups represent two-thirds of the ice bed. As a result, no individual bay exhibits a significantly disproportionate trend due to the azimuthal variance.

If the ice mass surveillance is performed on an as-found (pre-maintenance) basis, then the sublimation allowance is no longer needed in the technical specification and it can be moved to plant maintenance procedures that are maintained per the requirements of IOCFR50, Appendix B and 10CFR50.59. This allows ice baskets to be serviced in the plant maintenance program based on their individual basket sublimation rates, as opposed to assuming all baskets sublimate uniformly across the bed (an assumption clearly dismissed by the industry operating experience depicted in Figure 1-2). The practice of managing individual basket sublimation in order to maintain a relative distribution of ice across the bed is the foundation of the Active Ice Mass Management (ADMM) concept.

AIMM Methodoloai In order to perform appropriate replenishment activities on the ice bed each outage, the number of baskets needing to be serviced must be identified. Replenishment "triggers" vary from plant to plant due to variations in specific sublimation rates, but at all plants the as-found ice mass in each basket of the bed must be assessed prior to assigning replenishment scope. As shown in Figure 1-2, there are a significant number of baskets that will not need ice replenishment every outage (such as those in rows 1-6).

However, the current mass of ice in these baskets must still be determined in order to predict when they will need replenishment in the future. This process (assigning replenishment scope to the current and future outages based on current basket mass and known sublimation trends) is an active management TOPICAL REPORT ICUG-001, Revision 2 1-5 May 2003 DRAFT cQ'

process, requiring that plants know the specifics behind their ice bed's behavior patterns. In most cases, each individual basket in the ice bed has a known sublimation behavior pattern associated with it, based on its specific location. Upon determining the as-found ice mass for a basket in the bed, plant personnel then compare that value to the required safety analysis mean value and apply that basket's sublimation trend to project its mass forward through the coming cycle. Any individual basket's ice mass that is projected to sublimate to or below the safety analysis mean mass value is serviced during the current outage. This is how AIMM practice maintains the ice mass in each individual basket above the required safety analysis mean.

Determination of Basket Mass In AIMM Practice As noted previously, the preferred method for basket mass determination is via a load cell due to this method's relative speed and accuracy. As it requires the baskets to be free to be lifted, the use of this method is limited in areas of the bed where frequent servicing has rendered some baskets unliflable. In these areas, either historical sublimation trends are used to project a basket's mass to the present, or it is visually inspected (full length via camera) and its mass estimated. Since the historical technical specification surveillance requirements were performed in the as-left condition, all baskets used in satisfying the surveillance after servicing were required to be free so that a load cell could be used. In many cases, this resulted in the use of alternate selections in the areas where stuck baskets are common.

The technical specification approach supported by this topical report is an as-found surveillance, providing an opportunity for the industry to document these alternate methods of mass determination for satisfying the surveillance requirements. This is discussed in more detail in Section II.

The Radial Zone Concept Technological advances (such as ICEMANm) have allowed the industry to further develop AIMM methodology by simplifying the evaluation of empirical data and depicting long-term ice bed behavior.

As was done previously in Table 1-1 with defined azimuthal Groups, mean industry data can be used to show the radial row mean sublimation rates for each radial row (see Table 1-2). These sublimation rates are based on a population of 216 baskets per radial row and is consistent with data presented in Table 1-1, where radial row 9 designates the row adjacent to the Crane Wall. The data is shown graphically in Figure 1-3.

Table 1-2. Radial Row Sublimation Rates Radial Row Mean Sublimation Rate Standard Deviation 18 months)

I(bs (lbs/18 months) i  ; 9 153 56 8 97 22 7 60 10 6 38 10 5 24 1 4 16 12 3 - 11ll -7 7 2- - 18 -

2 14 25 1 16 30 TOPICAL REPORT ICUG-001, Revision 2 1-6 May 2003 DRAFIT

Figure 1-3. Radial Row Sublimation Rates (lbs/18 months) 180 V..,

160 140 -

120 -

100 -

80 -

80 -

40 -

20 -

0-Ro 9 RowRow Row O RowS8 A7 Ro R.

Row? Row O

]M.,.

Row 5 Rowd4 Row 3 Row 2 Row 1 Figure 1-3 clearly shows that certain radial rows sublimate at markedly different rates than other rows, with the most pronounced effect in the innermost radial rows 7, 8, and 9. The industry recognized that isolating these three radial rows would provide a "radial zone" that behaved, for all intents and purposes, as a separate entity. Through AR-IM practice, the baskets in radial rows 7, 8, and 9 are the most frequently serviced due to this sublimation rate difference, but not all rows are serviced at the same time (i.e., the same outage). It became apparent that because of this inherent replenishment schedule, these three rows contained similar mean mass at any given point in time. With radial row 9 serviced the most frequently, and rows 7 and 8 serviced less frequently, every ice basket in the "radial zone" could be used as a reasonable as-found (pre-maintenance) representative of the zone. The new ice mass surveillance, then, could easily be defined in terms of Radial Zones, where each Radial Zone was comprised of rows of ice baskets that historically conveyed similar mean mass for analysis purposes.

The Radial Zone concept was further supported by the idea that statistical analysis could be performed on individual Radial Zones to determine total ice bed mass with 95% confidence, which would considerably simplify the surveillance requirements. This led to a generic three sequential radial row, three Radial Zone configuration, which was based on the data depicted in Figure 1-3. It is noted, however, that this configuration is not the only one that will work; other, more refined approaches can be made with a similar technical basis.

To illustrate the adopted generic configuration, Radial Zones are defined such that Zone A contains Rows 9, 8, and 7; Zone B contains Rows 6, 5, and 4, and Zone C contains Rows 3, 2, and 1. Applying this concept to industry historical data results in a profile of mean sublimation rates, as shown in Table 1-3 and Figure 1-4.

TOPICAL REPORT ICUG-001, Revision 2 1-7 May 2003 DRAFT

Table 1-3. Radial Zone Sublimation Rates Radial Zone Mean Sublimation Rate Standard Deviation (lb/18 months) (lbs/18 months)

A 103 52 B 26 14 C 14 25 Figure 1-4. Radial Zone Sublimation Rates 120 Nth'"

• 00 so 40 20 Zone A Zone a Zone C The concept of Radial Zones is also applied to the alternate basket selection criteria, which provides for an alternate basket selection for the statistical analysis in the event an initial sample selection cannot be accessed. Since each Radial Zone consists of baskets having similar mean mass, all baskets in that Radial Zone are considered to be statistically representative for sampling purposes. This approach is discussed further in Section III.

Rectons of Localized Dearaded Mass A surveillance that requires a minimum total ice mass in each Radial Zone assures the initial conditions of the DBA analyses, and also assures that the ice mass is appropriately distributed across the three Radial Zones. A separate surveillance, addressing the potential effects of a localized area of baskets with degraded mass, adds assurance that AIBM practice is being implemented appropriately. As described previously, through AIMM methodology individual basket mass is managed above the required safety analysis mean value. The AIMM methodology provides defense in depth in complying with the surveillance requirement and minimizing any occurrences of baskets with ice mass less than the required safety analysis mean. The original licensing basis for the ice bed provides the concept that the DBA containment pressure response is relatively insensitive to variations in ice mass (Ref. 19). This concept is evident by the original Technical Specification provision for the treatment of "light baskets."

hi an effort to provide quantitative bases to link this concept to DBA safety analysis, Duke Energy ran a series of three-dimensional GOTHIC sensitivity runs (Ref. 21) using the McGuire Nuclear Station TOPICAL REPORT ICUG-001, Revision 2 I-8 May 2003 DRAFT

containment model. For the purposes of showing containment pressure response sensitivity to localized degraded mass conditions of varying severity, the GOTHIC results can be applied to all domestic ice beds.

For each of these sensitivity runs, an entire end sector of ice baskets (2.75 ice condenser bays side-by-side at the far end of the bed) was degraded, and the worst postulated DBA break positioned right under this region. As the GOTHIC analysis is a three-dimensional model and allows cross-flow between bays, choosing the end sector limited the advantage of steam cross-flow to only one adjacent sector after the degraded region melted through during the analyzed DBA transient. Three separate cases were defined:

• Case 1: All baskets in Radial Zone A bounded by the far-end GOTHIC sector (2.75 bays) contain 600 lb of ice each at the onset of the DBA. This represents 75 baskets, all grouped together, positioned over the break location. The results for this run showed that the resulting peak containment pressure was essentially unchanged, staying within about l2 % of the baseline case for McGuire.

• Case 2: All baskets in Radial Zone A bounded by the far-end GOTHIC sector (2.75 bays) contain 400 lb of ice each at the onset of the DBA. This represents 75 baskets, all grouped together, positioned over the break location. The results for this run showed that the resulting peak containment pressure increased, but was within about 2 °%of the baseline case for McGuire.

• Case 3: All baskets bounded by the far-end GOTHIC sector (2.75 bays) contain 400 lb of ice each at the onset of the DBA. This represents 225 baskets (all three Radial Zones), all grouped together, positioned over the break location. The results for this run showed that the resulting peak containment pressure increased, but was within about 2'/2 % of the baseline case for McGuire.

These results quantify the relative insensitivity of the ice condenser DBA containment pressure response to extreme ice mass variances, including worst-case break and mass variance- locations. As described previously, via AIMM methodology each basket is managed above the required safety analysis mean mass, so that variances of this severity due to maintenance practices are highly unlikely. Given this, a plant transient significant enough to open the Lower Inlet Doors is the only mechanism that might create the extent of degraded conditions depicted by these runs, and a transient significant enough to open the Lower Inlet Doors would be annunciated in the Control Room, initiating prompt corrective action.

However, because the sample baskets randomly selected in a Radial Zone are statistically averaged to satisfy the surveillance requirement for mean total ice mass, the Technical Specification technically allows some individual baskets to be below the safety analysis mean provided there are other higher-mass baskets in the sample to account for them. Therefore, a limit is established on the minimum allowed ice mass in any basket to assure that the potential for melt-through of any localized area of the ice bed will be consistent with the original DBA analysis concepts. For this reason, a minimum individual basket mass limit of 600 lb per basket is established as a separate operability requirement, such that there are essentially no effects on DBA containment pressure response. This as-found surveillance for minimum ice mass in any individual basket assures the bed condition is at all times consistent with the initial conditions of the DBA analyses, by limiting localized degradation that might challenge the DBA containment pressure response.

Conclusions Existing ice condenser design basis requirements show that the ice mass technical specification is satisfied as long as both the short-term and long-term phases of the DBA are accommodated by sufficient ice mass in the bed. Therefore, the new Ice Mass Technical Specification contains surveillance requirements that provide assurance the ice mass present in the ice bed at any given time, with a 95%

level of confidence, is sufficient to mitigate the overall DBA response. Specifically, the operability surveillances will be performed when necessary in the as-found (pre-maintenance) condition.

TOPICAL REPORT ICUG-001, Revision 2 1-9 May 2003 DRAFT

The minimum individual basket mass surveillance requirement is based on the minimum amount of ice needed in each basket to avoid localized regions of degradation in the ice bed that might challenge the DBA pressure response. This limit is derived from sensitivity runs performed using the three-dimensional GOTHIC analytical code. Concurrent assurance that localized regions of gross degradation do not exist in the ice bed is given via Active Ice Mass Management (AIMM) methodology, which is based on current industry maintenance practice and asserts that the ice mass in each basket in the ice bed will be managed above the required safety analysis mean, and serviced prior to reaching this limit. Therefore, the methodology for the requirement of minimum individual basket mass has two elements: I) active maintenance practice (AJMM) that manages each basket to the required safety analysis mean, and 2) a defined surveillance minimum limit of 600 lb per basket.

Assessment of total ice mass and distribution in the ice bed is facilitated by segregating the ice bed into Radial Zones, which provides basket sub-populations with similar characteristics. Individual baskets can, as a result, sublimate according to their relative position in the bed and remain operable provided minimum individual basket mass limits are maintained and the total ice bed mass requirements met. The generic Radial Zone configuration adopted by the industry is a three-Radial Zone, three sequential row array based on historical sublimation and mass data from the plants, and in addition to providing enhanced mass assessment provides assurance of appropriate mass distribution.

An as-found (pre-maintenance) surveillance that verifies the total ice mass needed to mitigate a design basis accident will require that each plant be cognizant of ice basket sublimation rates and the accuracy of mass determination methodology. Sublimation allowances for upcoming cycles and treatment of mass determination uncertainty will be maintained procedurally at each site.

TOPICAL REPORT ICUG-001, Revision 2 I-10 May 2003 DRAFT

II Ice Basket Mass Determination Methodology Purnose/Scone This Section describes the methods utilized to determine individual ice basket mass for the Ice Mass Technical Specification surveillance requirements, and provides a standard for developing, quantifying and maintaining the uncertainty for each of these methods. A description of available mass determination techniques is provided, along with a generic estimate of each technique's uncertainty based on analyzed industry data, which supports their use in the Statistical Sampling Plan (Section III) and in establishing a 95% level of confidence in the total ice bed mass. The methods analytically considered are manual lifting, basket mass projection using historical data and trending software (i.e., Excel spreadsheets, ICEMAN"M, or other), and visual inspection. The treatment in this Section of the uncertainty in the mass determination techniques provides a large range within which other methodologies can be developed as the industry's experience grows. The quantitative details regarding the determination of ice basket mass and associated uncertainty are based on the accumulation of actual field data and therefore must be maintained in plant-specific procedures in accordance with 10CFR50, Appendix B. This topical report provides the associated methodologies that are the standard within the industry.

The generic analysis herein is based on ice mass data (collected via lifting, visual inspections and software projections) from the last refueling outage at any plant prior to February 2001. As noted previously basket mass data and mass determination technique uncertainties for subsequent plant outages will necessarily change; however, the general trends and conclusions remain valid.

Discussion Preferred Ice Mass Determination Method Historically, the determination of ice basket mass and the collection of ice mass data have been accomplished through manual lifting of the basket. This method provides the fastest and most direct way of determining ice mass. In this process, the ice basket is raised by its top with a lifting rig, which is attached to a load-measuring cell (for indication of the mass). For most baskets, a hoist is used for the lift, a hydraulic cylinder is used for less accessible basket locations. The load cells are calibrated via plant procedures conforming to IOCFR50, Appendix B requirements.

The manual method works well unless the basket selected is stuck and cannot be lifted without exceeding established maximum lifting force limits. For ice baskets that are stuck, either the mass of the selected basket must be ascertained by some alternative means, or a representative alternate basket selected within the guidelines and limitations discussed in Section HI. If an alternate mass determination technique can ascertain the mass of ice in a basket, then the presence of stuck ice baskets is not relevant to the surveillance requirements.

Alternate Ice Mass Determination Methods In general, a valid alternate basket mass determination technique must have the following three qualities:

1. The technique must be predictable, showing that the uncertainty associated with the methodology is based on sound analysis that is maintained to account for current experience levels, including actual accumulated field data, TOPICAL REPORT ICUG-001, Revision 2 11-1 May 2003 DRAFT

2. The technique must be repeatable, showing that its continued use does not generate values consistently outside the established uncertainty of the method, and

3. The technique must be shown to apply to the specific ice bed under surveillance, showing that the methodology is supported by valid local data.

As noted in Section 1,ICEMANTh is a software program that trends ice basket mass histories and can be utilized to project future ice basket mass based on individual sublimation rates and previous ice basket mass data. Likewise, other software applications can be used, such as Excel spreadsheets or similar commercially available products. Any of these utilized applications are maintained on a plant-specific basis in accordance with the requirements of IOCFR50, Appendix B.

The projection technique has been used successfully for many years at Duke Energy's McGuire and Catawba Nuclear Stations to predict outage maintenance scope. As an alternate mass determination technique, it represents the most precise technology outside the manual lifting method, but requires a significant amount of accurate historical ice mass data in order to generate projections. This technique entails observing the mass of individual ice baskets over a period of time (many cycles), and, through successive end-of-cycle weighings of the basket, determining the total ice loss that occurs over the period.

From this information, a sublimation rate is calculated, and when a projection of the basket's mass is required (i.e., if the basket were to become stuck), the sublimation is extrapolated to the desired date (e.g.,

the end of the current cycle) from the last known lifted mass. This technique requires a data validity criterion (described later), which limits the use of the most historically distant data in projecting a current basket's mass and also limits the number of times a given basket's mass can be projected successively before a lifted mass on the basket is required. It also requires that the uncertainty calculation be updated with newly obtained data after each outage to reflect the most recent sublimation trends in the ice bed.

The end-of-cycle mass data, being obtained by manual lifting, limits the technique's capabilities as an as-found surveillance tool where a large number of stuck baskets have existed for some time. In this case, Licensees have the option of getting these stuck ice baskets free (e.g., via labor-intensive means) and keeping them free for several successive cycles to refresh the sublimation trend, or not using the projection technique. In the latter case another mass determination method would be required.

Sequoyah Nuclear Plant has developed and employed a procedure for performing a visual inspection of the ice basket column in order to determine its mass. This method involves a camera inspection over the length of the ice basket while estimating the amount of ice mass missing from the column in the form of linear gaps, shaped voids, and annular "shrink-back" from the ice basket mesh. The mass of missing ice from the various voids is totaled and the result subtracted from the known mass of a full basket, providing an estimate of the actual ice mass in the basket. This technique has been utilized successfully over several outages at Sequoyah as a scoping technique for outage maintenance, and is used in areas of the ice bed where stuck baskets are typically found (e.g., Radial Zone A). Experience with the visual estimation technique has shown that a reasonable assessment of ice basket mass can be made; some ice baskets found stuck and their mass estimated using this technique have been subsequently freed and manually lifted, giving a direct comparison for analytical purposes. In addition, ice baskets recently lifted have been visually estimated to provide additional data. As with the mass projection method described previously, this method of mass estimation requires a validity criterion requiring comparative determination of ice mass using the lifting method in order to maintain a quantifiable uncertainty. As the most subjective of the three methods defined so far, visual estimation of basket mass, used on a large scale, will likely require Licensees utilizing it to maintain more ice in their ice bed due to the greater uncertainty associated with this method.

In order to assess the viability of other alternate mass determination methods, TVA commissioned a study through an independent consulting company to investigate new technologies for non-intrusive inspection of the ice column profile in the ice baskets. The goal of the study was to find a technology that would provide an estimation of the volume of the column and therefore the mass of the ice in the column. Based TOPICAL REPORT ICUG-001, Revision 2 11-2 May 2003 DRAFT

on the results of the investigation it was concluded that the use of ultrasonic measurement techniques was best suited to this application, with laser technology also recommended. In both cases, inspection of the ice column requires a scanning device to be sent along the length and periphery of the ice column. The delivery system and hardware pose a significant challenge in developing this technology. TVA elected to proceed with the development of the ultrasonic measurement technique. A prototype system was assembled and given a proof-of-concept test at the Watts Bar Nuclear Plant; the test concluded that the prototype system was able to profile the surface of the ice in a basket and that the data could be recorded for future analysis. However, challenges identified with the delivery mechanism for the ultrasonic probe and the retrieval of the data collected from the scan need to be resolved before this technique can be successfully utilized as an alternate mass determination method.

For any of the alternate mass determination methods described herein (or for methods subsequently developed), quantitative validation of the technique will be maintained on a plant-specific basis in documents developed under the auspices of 10CFR50, Appendix B and IOCFR50.59. Quantitative validation determines the specific uncertainty of the methodology, and identifies the associated measures of relative standing (e.g., systematic bias and random error). Individual ice basket masses determined using an alternate technique are quantified using a standard method agreed upon by the industry, which facilitates the determining of total ice bed mass as described in the Statistical Sampling Plan (Section IHo).

In addition, this method provides for showing the predictability and repeatability of the techniques, as well as documenting the plant-specific data used to develop them.

Standards:Ice Basket Mass DeterminationUncertalnty This section considers the error and uncertainty in measurements and calculations performed while determining the mass of individual ice baskets, and provides a model by which the uncertainties inherent in different methodologies for determining individual ice basket mass can be defined.

As discussed previously, there are three documented methods used for determining the mass of an ice basket:

1. Direct lifting of the basket with a lifting rig utilizing a calibrated load cell,

2. Projection of the basket's expected mass from historical data and calculated sublimation rates (determined using mass data obtained by load cell), and

3. Visual approximation of the basket's mass made from a full-length inspection of the ice basket using a video camera.

All of these methods rely, to some degree, on basket mass data obtained through the use of a load cell device. Methods 2) and 3) were uniquely developed to facilitate determining the mass of baskets that cannot be directly lifted due to obstruction or ice build-up around the basket's periphery, a situation that occasionally occurs in some baskets that were initially free to lift. For each of these methods, the uncertainty in the mass determinations must be defined prior to their use in satisfying technical specification surveillance total ice bed mass requirements. The application of these individual uncertainties to the appropriate surveillance requirements is discussed in detail in Section m.

Concepts regarding uncertainty

> Every measurement has an uncertainty associated with it, unless it is an exact, counted integer.

> Uncertainty arises from errors introduced into the measurement process, and errors arise from both systematic bias and precision-relatedissues.

TOPICAL REPORT ICUG-O01, Revision 2 11-3 May 2003 DRAFI

> Every calculated result also has an uncertainty, related to the uncertainty in the measured data used to calculate it.

> The numerical value of a

• uncertainty value provides the range of the result. For example, an ice basket mass identified as 1,465 4 15 lb means that there is some degree of confidence that the true value falls between 1,450 lb and 1,480 lb.

Error The error in a measurement is the difference between the measurement and the actual or true value of the quantity observed. Since the true value is often not known, the exact error is also unknown.

Errors are typically divided into two types: systematic and random. Systematic errors (also known as bias) can result from fundamental flaws in the equipment, the performer, or in the use of the equipment.

For example, a load cell may always read 5 lb light due to being zeroed incorrectly. Similarly, a member of a weighing crew may consistently overestimate a visual estimation of ice mass in a basket. This type of error, if it cannot be calibrated out (as might be the case with a mass measurement made by visual estimate or sublimation projection rather than an instrument), must be identified and included in any measurement uncertainty.

Random errors vary in a completely non-reproducible way from measurement to measurement. However, random errors can be treated statistically, making it possible to relate the precision of a calculated result to the precision with which each of the measured variables (such as individual basket mass) is known.

Random error is typically estimated by the standard deviation (denoted by a) of a group of repeated measurements centered about a mean.

To assist in recognizing types of error, consider the task of measuring the distance between two parallel vertical lines drawn on a piece of paper. Typical technique would be to use a ruler, aligning one end of the ruler with one line, and reading off the distance to the next. Random errors might arise from two sources:

1. Instrumental error (e.g., ruler calibration, spacing and size of the ruler's graduations), and

2. Uncertainties in the lines (e.g., thickness of lines, temperature and humidity effects on the paper).

A third source of error also exists, however, related to how any measuring device is used. In this case, the error might be made aligning one end of the ruler with one line. The ruler should be placed on the first line randomly (but as perpendicular to the lines as possible), the position of each line on the ruler noted, and the two readings then subtracted. This should be repeated several times, and the differences averaged.

This process eliminates the systematic bias (i.e., the error that occurs in each measurement as a result of the measuring process itself) that aligning one end with one line introduces.

A final type of error must be mentioned as well: erraticerror (or a blunder). These errors are the result of a significant mistake in the procedure, either by the performer or by the instrument. An example would be misreading the numbers on a load cell read-out and entering incorrect information into the basket mass history database. Another example would be unnoticed excessive friction between the sides of a basket and the lattice steel while using a lifting rig with a load cell. The load cell itself might produce a blunder if a poor electrical connection causes the display to read an occasional incorrect value. If the mistake is caught at the time of the procedure, the result should be discounted and the measurement repeated correctly. If the mistake is missed, blunders can be difficult to trace and can give rise to much larger error than random errors. If a result differs widely from a known (or expected) value or has low accuracy, a blunder may be the cause. If a result differs widely from the results of other performed measurements, a blunder may also be to blame. The best way to detect blunders is to repeat all measurements at least once TOPICAL REPORT ICUG-001, Revision 2 114 May 2003 DRAFT

and compare to known or expected (benchmark) values, if available. Blunders can also be avoided through careful application of procedural controls for the measurement process.

Precision of Instrument Readings and Raw Data The first step in uncertainty determination for a process or calculation is to estimate the precision of the raw data used in the calculation. Consider three mass determinations made on the same ice basket using a load cell w/digital read-out as follows (all are basket + ice):

Ist weighing = 1,652.1 lb 2nd weighing = 1,654.3 lb 3rd weighing = 1,656.2 lb The average, or mean, mass of the ice basket is therefore:

M..ican= 1,652.1 + 1,654.3 + 1,656.2 = 1,654.2 lb 3

In this example, the precision or reproducibility of the measurement is + 2 lb. All three measurements can be included in the statement that the basket has a mass of 1,654 + 2 lb. The load cell read-out in this example allows direct reading to one decimal place, and since the precision is roughly 2 lb, the load cell has the necessary sensitivity for this measurement.

At this point, there is little knowledge of the accuracy of the mean basket mass, 1,654 +/- 2 lb. The accuracy of the weighing process depends on the accuracy of the internal strain gauges in the load cell as well as on other instrumental calibration factors. The manufacturer's stated accuracy for this load cell is +/-

0.3% of full scale, which for a 0-5000 lb scale is about + 15 lb. This is verified every time the load cell is calibrated, and often the accuracy achieved is better than that stated by the manufacturer. Since the measurements are also being made well within the full scale range of the load cell, it can be expected that a correctly calibrated instrument, used according to procedure, will give an accurate result. Therefore, in this example the precision displayed by the measurements is well within the expected calibrated uncertainty of the load cell. The high precision of the three measurements (* 2 lb) indicates that a blunder has not been made, and in addition shows a reduced likelihood of significant systematic bias.

Quantifying Measurement Uncertainty For simplicity of presentation a single number (some combination of systematic bias and random error) is needed to express a reasonable limit for uncertainty. The single number must have a simple interpretation (the largest error reasonably expected) and be useful without complex explanation. It is not feasible to define a single rigorous statistic, because systematic bias is an upper limit based on judgment and experience with a particular process which has generally unknown characteristics. The function, then, must be a hybrid combination of an unknown quantity (systematic bias) and a statistic (random error).

At this point, the adoption of a standard for defining basic uncertainty is appropriate. The standard most frequently used is the bias limit plus a multiple of the random error. This method is recommended by the National Bureau of Standards and has been widely used in many industries. Utilizing this standard, uncertainty may be centered about an individual measurement and defined as:

U = +/- [B + (t95. xr)]

Where B is the systematic bias limit, a is the random error, and ts is the 95h percentile point for the two-sided Student's "t" distribution. The value of tgs is a function of the degrees offreedom (or sample size) used in calculating a. For small sample groups, t9s will be large, and for larger sample groups, t95 will be smaller, approaching 1.96 as a lower limit (for sample groups > 500). The use of t95 arbitrarily inflates the TOPICAL REPORT ICUG-001, Revision 2 11-5 May 2003 DRAFT

uncertainty U to reduce the risk of underestimating a when a small sample is used to calculate it. In essence, the 95" percentile points in a two-sided distribution capture 95% of the population of measurements centered about the mean value.

In view of the above discussion, clarification is needed regarding the proper quantification of individual ice basket mass determination uncertainty values that are to be used in satisfying legal technical specification surveillance requirements. Because of the nature of the technical specification limits (i.e., a minimum allowable ice mass for legal operability), it is industry convention to use a one-sided interval for uncertainty, to ensure only conservative (ie., lower) values of basket mass are included in the calculations. For example, an ice basket mass of 1,642 + 15 lb would propagate to the surveillance requirements as 1,627 lb (in actual practice the tare weight of the ice basket would also be removed in order to reflect the ice mass available for pressure mitigation alone). In the case of a biased uncertainty (where B ,40), a non-conservative bias component (i.e., one that raises the apparent mass determined using that process) would not be included in the uncertainty, while a conservative bias component (i.e.,

one that lowers the apparent mass determined using that process) would be included.

Because of the one-sided convention, the quantification of uncertainty for ice mass determinations will take the form:

U = - [B + (t9s. A)]

The value of t95 will also change to the value corresponding to a one-sided test, which approaches 1.645 as a lower limit (for sample sizes > 1000). Standard tables for the critical values of t for one- and two-sided tests and for various sample sizes are available in Reference 25, or in any statistics text.

For the load cell (an instrument calibrated in a standards laboratory prior to being used), the stated measurement uncertainty should contain no systematic bias components. Repeating individual basket mass measurements in the field will further reduce the risk of inserting procedure-related systematic bias into the process. Therefore, in the three-basket mass determination example described previously, the basket mass would be quantified as 1,642 +/- 15 lb (or whatever the calibratedaccuracy of the load cell turned out to be).

For more subjective basket mass determination methods other than direct lifting, such as the mass sublimation projection and visual estimation processes, it is imperative that uncertainty components (systematic bias, random error, and degrees of freedom) be defined and available in supporting documentation. These three components will be required to: 1) substantiate and explain the uncertainty value, and 2) provide a sound technical basis for improved measurements. In addition, the individual uncertainty components are applied independently to the required 95% confidence interval calculation of ice mass (as described in Section o) in the technical specification surveillance requirements, and documenting them in this manner facilitates that usage.

Historical Data Validity - Alternate Ice Mass Determination Methods The two currently defined alternate techniques for determining individual ice basket mass are:

1. Projection of a basket's future mass via a sublimation trend calculated using accumulated data from historical load-cell determined values for that basket, and

2. Visually estimating a basket's mass by accounting for the voids present in the sublimated basket, and subtracting the associated "missing mass" from a pre-defined full basket mass value.

Since neither of these techniques directly involves a measuring instrument, "calibration" occurs through data analysis and refinement of the techniques. Applying an uncertainty value to either of these TOPICAL REPORT ICUG-001, Revision 2 11-6 May 2003 DRAFT

techniques using outdated historical data is not an acceptable way to verify that the procedure is a valid alternate mass determination process. Therefore, the following is the industry standard for refreshing the historical data used to validate these two methodologies:

Table 2-1. Alternate Mass Determination Technique Data Refreshment Criteria Mass data used for uncertainty calculations must derive from:

• 2 3 of the last 6 operating cycles, or

• 2 out of the last 3 operating cycles.

For the mass sublimation projection technique, this represents 1,500 to 3,000 days of current sublimation data or about 1,000 days of the most recent data for the associated basket to determine average sublimation rates. For the visual estimation method, this criterion links the data used in the analyzed distribution to the most recent experience with the technique, and limits the number of successive times the technique can be used on an individual basket before a benchmark lifted mass on the basket is obtained.

Another important aspect of data validity involves the qualification of personnel trained to perform alternate mass determination techniques. In the case of mass sublimation projection, extrapolation of a point from historical data is much less subjective than accounting for visually estimated voids in an ice basket. For this reason, the latter methodology would be expected to require a rigorous training and testing protocol to ensure that accumulated data used to identify and ultimately refine process uncertainty has the highest practical quality. An efficient way of handling this is through a standardized "test" that displays the most commonly observed void characteristics in a sublimated ice basket, and depicts those voids in actual ice bed conditions (e.g., low lighting, less than ideal camera focus, space limitations).

Video tapes, in situ estimations during scheduled outages, and practice with mock-ups are all appropriate for establishing this quality. In addition, a visual acuity test would be required to ascertain the ability of the performer to evaluate these voids in the ice bed, and qualification of the equipment provided to perform the procedure (i.e., camera, lighting) must be made.

By defining the historical data validity standard in this way, plants can ensure consistent documentation and application of the uncertainty values used in satisfying the legal technical specification surveillance requirements. This standard is applied through incorporation in plant-specific procedures that are maintained in accordance with IOCFR50, Appendix B.

Examples The following two examples illustrate the statistical analysis of historical data for both the sublimation projection and visual estimation alternate ice basket mass determination techniques. The data analyses are performed to identify the uncertainty components for each method, and provide an outline by which plant documentation can be generated that conforms to the standard model presented herein. In these examples, the actual data sets (i.e., the individual basket mass measurements) are not shown due to their size, but represent typical industry data nonetheless. It can be assumed that all data were collected/calculated via established procedures by personnel qualified to perform them.

TOPICAL REPORT ICUG-001, Revision 2 11-7 May 2003 DRAFT

Mass Sublimation Projection UsingHistoricalData There are several different ways to determine the sublimation rate of an individual basket using historical data. The method used primarily by the industry involves reviewing up to six previous operating cycles' worth of data for a basket (in accordance with the criteria established previously) and determining, from successive load cell mass determinations on the basket, the total quantity of ice loss that has occurred over the period. The result is a linear depiction of sublimation, with the rate of sublimation represented by the slope of the line. The unbiased uncertainty (e.g., + 15 lb) involved in the individual measurements of mass made over this period using the load cell is typically a constant and therefore does not change this slope, but does affect the location of the line. If the next point along the line is to be projected (extrapolated using the slope) rather than identified via load cell, an uncertainty is inserted because the slope is an approximation of sublimation based on many varying parameters, such as operating cycle transients, air handler unit performance, and even seasonal factors. At the outcome of this projection, the historical load cell uncertainty is added to the projection uncertainty, as it becomes a "known" form of systematic bias.

For this example, mass data for 1,024 ice baskets were collected over six consecutive outages in a particular ice condenser. At the end of the last operating cycle, these baskets were weighed with the load cell and their mass also individually projected using the sublimation rate determined by this historical data. The two values for basket mass were then compared and the differences between them categorized into "ranges" of mass difference as follows:

Table 2-2. Projection Method Example Data tI TPro ected Mass) -(Lifted Mass) Results Range Frequency (lb) # baskets In range)

-100 + 2

-99 to -71 3

-70 to -51 6

-50 to -41 18

-40 to -31 62

-30 to -16 175

-15 to 15 553 16to30 119 31 to 40 42 41 to 50 12 51 to 70 24 71 to 100 5 100+ 3 Total 1,024 Ranges were chosen based on an inspection of the data spread and on those groupings that would facilitate insight into comparison with load cell accuracy.

From this table of results, it can be seen that a fairly symmetric distribution of points exists, centered about the range -15 to + 15 lb. Note also that a positive difference (> 0 lb) is representative of a non-conservative projection of mass, that is, the projection was higher (indicated more mass) than the benchmarked load cell data point, which is considered more accurate. In terms of uncertainty, however, this is conservative, since it increases the error band. Graphically, this data can be represented as:

TOPICAL REPORT ICUG-001, Revision 2 11-8 May 2003 DRAFT

Figure 2-1. Projection Method Example Chart Projected Ice Basket Mass Results 600 550 500 450 400 350 8

iZ 300 9

250 200 150 I

100 50 0

A' N N !PxZ

!"',Ae oe, '40 +~p t..O N, 0

eP ~"$ 'Po ,-

L In order to determine the expected uncertainty to be included for baskets using this technique based on the collected data, recall from the previous discussion that the systematic bias, random error, and the degrees offreedom (sample size) must be identified.

The systematic bias and random error can be determined from the comparison data by calculating the mean difference and its standard deviation. Performing these statistics operations (the actual 1,024 compared data points are not presented here for clarity) yields:

Mean Difference = -1.7 lb = -2 lb Standard Deviation = or = 24.5 lb = 25 lb "Rounding" (conservative measure based on knowledge of the data and associated significant figures) is used here since these values were computed from individual basket mass measurements that have an explicit uncertainty of +/- 15 lb (the calibrated, unbiased load cell accuracy). The implicit accuracy of the load cell measurements is to three significant figures (e.g., 1,642 +/- 15 lb would be written 1,640 lb). As such, recording these two statistics to +/- 0.1 Ilb, while technically allowed, is not practical.

For the calculation of the systematic bias, B, two values will need to be applied: the calculated mean difference of the data set and the offset associated with the accuracy of the benchmark value. If the mean difference is negative (i.e., non-conservative), then it is set to zero, and the benchmark value (load cell error) assumed for the value of B. If the mean difference is positive (i.e., conservative for uncertainty),

then the load cell error and mean difference are added together to determine the systematic bias component.

TOPICAL REPORT ICUG-001, Revision 2 11-9 May 2003 I)A 1'"1'

The sample size in this case is 1,024 baskets, which corresponds to the lowest one-sided test value for tq5 (the 95w' percentile point for infinite degrees of freedom). So, from the tabulated values in Reference 3:

t95 = 1.645 From this analytical observation of the collected data points, the uncertainty for this mass projection technique can be calculated as:

U = - [B + (t9, x r)]

U = - [B + (1.645 x 25)]

Since the mean difference is negative in this case, which is non-conservative in terms of uncertainty, set B

= 15 lb (the propagated load cell error), and:

U = -[15 + (1.645 x 25)] = -[15 + 41]

EfU-561 I This is an example of the quantified uncertainty that would be included when utilizing projection of ice basket mass. The minus sign indicates that, for analytical applications regarding compliance with the technical specifications, the mass is always reduced.

VisualEstimation of Ice Basket Mass Estimating the mass of an individual basket via visual inspection of the voids in the ice contained therein is a somewhat more subjective procedure than sublimation projection. Along with the previously described variables, the visual estimation technique contains other sources of error such as lighting, camera resolution, blockage of view due to frost build-up on the basket surface, and the procedural convention of assuming voids are symmetric, among others. It should be expected, then, that this technique will yield uncertainties that are larger, due to the increased likelihood of systematic bias and a wider distribution of data around the mean (random error). In addition, the mass of an ice basket is determined by subtracting the mass represented by the inspected voids from a "full" basket mass, which introduces further chance for error by requiring an assumed constant density of compacted flaked ice (to determine mass from volume measurements).

It is beneficial to accumulate as much individual basket mass data as possible using a consistent, well-written visual estimation procedure performed by personnel qualified to a standard test, and to obtain load cell data on these same baskets as a correlation. Having established that, and verifying that the data being analyzed for uncertainty determination conforms to the standard set for validity discussed previously, the statistical approach can be used to isolate the required measures of relative standing of the data set to determine the uncertainty as was done for the mass sublimation projection technique.

For this example, 238 individual basket mass data points were collected over two of the last three cycles for a particular ice condenser. Each of these baskets was visually estimated by established procedure and had a corresponding mass determined via load cell (with an unbiased uncertainty of

• 15 lb). Using the same style of presentation as the projected mass example earlier, the following table of compared values was generated:

TOPICAL REPORT ICUG-001, Revision 2 11-10 May 2003 DRAFr

Table 2-3. Visual Estimation Method Example Data

isua Iy stlimatebdMass> (Lifted Mass) Results Range Frequency (lb) (# baskets in range)

-400to-499 2

-350 to -399 1

-300 to -349 I

-250 to -299 8

-200 to -249 6

-150 to -199 9

-100to-149 15

-50 to -99 18 0 to -49 21

+1to +50 28

+51 to +100 28

+101 to +150 29

+151 to +200 21

+201 to +250 23

+251 to +300 15

+301 to +350 7

+351 to +400 2

+401 to +499 4 Total 238 Again, it can be seen that a fairly symmetric distribution exists for this data, though it appears to be biased non-conservatively for the basket mass determinations (i.e., it tends to show more ice mass than is actually present). This indicates that a positive bias will add to the uncertainty, unlike in the previous example. Graphically depicted, the comparative results for the visual estimation technique look like this:

Figure 2-2. Visual Estimation Method Example Chart TOPICAL REPORT ICUG-001, Revision 2 11-11 May 2003 DRAFT

From the comparison data (again not presented here for clarity), the systematic bias, random error and degrees of freedom are determined:

Mean Difference = 57.7 lb = + 58 lb Load cell (correlation) uncertainty = + 15 lb Standard Deviation = a = 166.7 lb = 167 lb Degrees of freedom (sample size) = 238 Note that the mean difference and random error values are again rounded conservatively.

For a sample size of 238, the one-sided distribution 95"' percentile point is defined by a t95 value equal to 1.65. Therefore:

U = - [B + (t95 X 0 U = - [B + (1.65 x 167)]= -[(58 + 15) + 276]= -[73 + 276]

U-3491b In this case, the uncertainty is a true combination of bias (73 lb) and random error (276 lb). Again, the minus sign indicates the conservative convention for the one-sided interval; however, when applying this uncertainty to the surveillance requirement calculations for estimating total ice bed mass, the bias and random error components are accommodated separately.

Example Summary These examples illustrate a statistical method of identifying the uncertainty due to systematic bias and random errors in the determination of individual ice basket mass. As expected, the uncertainty value for the visual estimation mass determination technique in the example is significantly higher: six times that predicted by the sublimation projection technique example, and over twenty times that determined by a typical load cell measurement made by direct lifting. This spread in the uncertainty values properly reflects the inherent subjective nature of the alternate mass determination techniques. In order to reduce the uncertainty of these methods, there are several approaches that can be taken:

1. Minimize the t9s value by keeping the comparative sample size large. This requires the accumulation of large quantities of basket mass data using the alternate techniques, an effort that will provide experience with the techniques as well as recent, valid information in accordance with the standard.

2. Refine the subjective measurement techniques, thereby eliminating sources of bias and random error that are introduced. Experience through outage data collection as well as through practice on mock-ups all provide opportunities for process refinement. Also, improvement in the tooling used (such as cameras and lighting) will be beneficial.

3. Improve the accuracy of the benchmark by calibrating the load cell to a higher standard. The load cells used in the industry can generally be calibrated better than the manufacturer's stated accuracy.

4. Improve the consistency of the input data (i.e., the individual basket mass data) for the more subjective measurement techniques. This can be accomplished by qualifying each performer of TOPICAL REPORT ICUG-001, Revision 2 11-12 May 2003 DRAFT

the visual estimation technique to a rigorous test standard, and by providing a well-written estimation procedure.

Conclusions The manual lifting technique provides the fastest and most accurate method of determining ice mass. For baskets that are stuck, there are two alternate ice mass determination methods that have industry standards developed. These are:

1. Projection of ice basket mass using software and historical data, and

2. Visual inspection of the ice basket.

In general, the software projection technique provides the most accurate alternate mass determination method, but it requires several sets of quality data in order to provide valid results. Further, its projections for a given ice basket are invalidated if the subject basket becomes stuck (unliftable) and is serviced anyway, thereby creating an unsubstantiated change in the mass of ice in the basket. The accuracy and consistency of software projections is dependent upon population and replenishment of the database with recent ice mass data (as required by the data validity standard) obtained via manual lifting.

The visual inspection technique offers another method of ice basket mass determination, useful due to its ability to estimate the mass of stuck baskets, most notably during an as-found surveillance. Like the software projection method, the accuracy of this technique is a function of the amount of data that has been collected, but it has other influences as well, such as procedural experience and basket surface ice.

Based on the subjective nature of the estimation process involved and as depicted by the examples, the visual inspection method typically has a lower accuracy than the ICEMAN' projection. However, once the uncertainty in the methodology has been defined in accordance with the industry standard, it can be utilized on an ice basket to estimate its mass, and represents an acceptable alternative approach to assessing ice basket mass for the purposes of the surveillance. As discussed in Section m, the larger uncertainty involved with this methodology may necessitate larger initial statistical sample groups in affected Radial Zones in order to adequately assess the minimum mass requirement (i.e., reduce the statistical penalty associated with taking a smaller sample), and will likely also require the Licensee to maintain more ice in these Radial Zones to account for the technique's lower accuracy.

The hierarchy of techniques, as described in this Section and outlined in Figure 0-1, is as follows:

1. Upon randomly selecting an ice basket for the surveillance, attempt to lift the basket using a lifting rig and an attached load cell device. If this is unsuccessful (i.e., if the basket is stuck or otherwise obstructed), Licensees have the choice of an alternate mass determination technique (if their plant procedures document one), or selecting an alternate basket for the surveillance subject to the given limitations (discussed in Section o).

2. If an alternate mass determination technique is available and utilized, the documented uncertainty is applied to the measurement in accordance with the established uncertainty standard, and this result carried through to the statistical sampling plan (outlined in Section O).

3. If the mass of the randomly selected basket for the surveillance cannot be ascertained by any available means, an alternate selection must be made subject to the given limitations (discussed in Section EI[).

As with all subjective techniques, proper training of personnel, well-written procedures, and proper qualification of associated equipment are required to properly document the alternate mass determination methodologies and reduce the uncertainties associated with them. The plant-specific documentation of mass determination technique uncertainty values will include the uncertainty calculations and associated valid data from that plant in accordance with the standard established herein, as well as supporting procedures and training/equipment qualifications in accordance with 10CFRSO, Appendix B.

TOPICAL REPORT ICUG-001, Revision 2 II-13 May 2003 DRAFT

III Ice Mass Statistical Sampling Plan Purpose/Scone The purpose of this Section is to provide the basis for the statistical sampling plan that will be used to demonstrate that adequate ice mass is maintained in the ice bed throughout the operating cycle. The statistical sampling plan, as developed herein, addresses the sample size, statistical approach, the effect of mass determination uncertainty, and the selection of alternate sample baskets.

Ice Mass StatsticalStrategy The objective is to estimate the total mass of all of the ice baskets in the ice bed based on a sample of those baskets. Since the standard deviation of the true individual masses of the ice baskets is not known and the number of samples taken is relatively small, the statistical "Student's t-test" applies (Section 3.5.2 of Reference 11, and Chapter 8 of Reference 12). The Student's t-test is used to establish how much the actual mean ice basket mass (p) could be less than the mean ice basket mass observed in the sample (X ). A confidence level (1-a) is associated with this lower bound (pt<). For the mean basket mass, a confidence level of 95% has been selected. Using the t-test, it can be established that there is 95% confidence that the actual mean ice basket mass is greater than some value, is,<. Figure 3-1 provides an illustration of the Student's t-test.

Figure 3-1. Illustration of Student's t-Test Ice Basket Mass Xk (Ib)

Mean Mass Per Basket in Sample Population t1-a *n Mean Mass Per Basket in jul-a Entire Population, with 1-a Confidence TOPICAL REPORT ICUG-001, Revision 2 111-1 May 2003 DRAFT

Using the "Student's t-test," with 1-a confidence, the mean individual ice basket mass is at least:

[ XC] (Equation 3.1)

Where:

.gl-a= Mean mass per basket of the total population with 1-a confidence X = Mean mass per basket of the sample group of size n tja = critical value of t that is a function of the confidence interval I-a and the degrees of freedom in the sample (n-i). This value can be obtained from References 9, 11, and 12.

1-a = confidence interval = the fraction of the estimated intervals (calculated from all possible sample populations and using Equation 3.1) that can be expected to include the true or actual average of the total population (Section 3.5, Reference 11)

X(X; X) 2 s = standard deviation of the sample group =

n-i Xi = mass of i-th sample (corrected for systematic bias)

CF = ( N- = Correction factor for a finite population (References 8, 11, and 13) n = total number of baskets in sample N =total number of baskets in the population represented by the sample The second term in Equation 3.1 represents the error of the mean. This error represents the fact that the mean mass per ice basket calculated from a sample group may differ from the actual mean mass of the parent population. To obtain the total mass of the ice bed with 95% confidence, the individual mean ice basket mass determined from the sample group, plI is multiplied by the total number of baskets in the parent population.

Equation 3.1 is the standard approach, used for analyzing a distribution of mass data that does not require addressing the uncertainty in individual measurements. The use of Equation 3.1 would require measurement uncertainty to be addressed generically elsewhere, such as in the surveillance limit. In cases where the accuracy of the mass determination methodology used is low or varies, it must be accounted for in the calculation of the errorof the mean. This would be the case when methods other than direct lifting using a scale or load cell are used in determining individual ice basket mass. As such, the following equation derived from the discussion in Section 8.3.1.1 of Reference 11 will be used to calculate the lower bound of the mean individual ice basket mass:

TOPICAL REPORT ICUG-001, Revision 2 111-2 May 2003 DRAFT

1 = X-a tifQ [j x CF] + IW2 (Equation 3.2)

Where:

j = number of mass determination methods used ni = number of baskets within the sample whose mass is determined by method i a0 = the random errorof the mass determination method i With this approach of accounting for the random error of the mass determination method (i.e., the variation of the measurement!, any systematic bias (an error which remains constant over replicate measurements; see Table 14.1, Reference 11) of the mass determination method is applied to the individual basket mass values prior to calculating the mean basket mass and standard deviation of the sample group. In other words, the mass of a given ice basket is adjusted for the systematic bias of the mass determination method used, before the mass value is used as an input to Equation 3.2. The random errorof the mass determination method (ai ), should be equivalent to one standard deviation.

In this equation, the variation of the process (as compared to the variation of the measurement) is represented by the observed sample standard deviation, s. It is important to note that this will insert some conservatism because the observed sample standard deviation will include effects of the measurement variation, which will, to some degree, be expected to increase the standard deviation.

For the purposes of the Ice Mass Technical Specification supported by this topical report, Equation 3.2 will be the assessment method.

Sample Size In using Equation 3.2, the sample size n considers the following:

1. The "Student's t-test" is based on a normal distribution. However, Reference 9 indicates that unless the number of samples is less than about ten, the assumption that the subject population follows a normal distribution will not significantly affect the validity of the results obtained, even if a normal distribution is not present.

2. The desired interval, or in this case the lower bound of the mean basket mass, will affect the sample size since typically the more samples taken, the narrower the interval tends to become.

3. The sample size is generally selected independent of the population size, if the population size is sufficiently large. However, the population may be stratified or broken into groups that are expected to have similar characteristics (e.g., mean and standard deviation). If this approach is used, the sample size is defined in terms of the stratified population group (such as n samples out of all ice baskets in a defined Radial Zone as a fraction of the 1,944 baskets in the entire ice bed, as discussed in Section 1).

While it is not considered necessary, the normality of a sample may be verified by using the methodology given in Reference 10. Random, statistically representative samples will generally result in fairly normal distributions. However, as mentioned previously, even if the sample is not normal, the "Student's t-test" will provide valid results as long as a sufficient number of samples are taken.

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Figure 3-2 provides an illustration of the relationship between number of samples and the error of the mean, assuming for the purpose of the example that there is no error in the measurement technique, and the standard deviation of the sample group is 100 pounds (which was selected considering typical standard deviations seen in ice condenser basket populations). In reality, there would be uncertainty in the measurement technique, and the curve in Figure 3-2 would be shifted upward. The figure demonstrates that once the number of samples is increased beyond approximately 30, the reduction in the error of the mean levels out. However, further reduction as a result of taking more samples may still be beneficial.

Figure 3-2. Effect of Sample Size on the Error of the Mean (assume s = 100 lb and no measurement technique error) 9 120 I 100 0o 0 20 40 60 so 100 120 140 1S0 18O 200 30 Number of Samples Experience has shown that a representativesample, such as the one utilized in the original Ice Mass Technical Specification and described in Section L could provide more useful information than a blind random sample. Therefore, the overall sample size may be driven more by obtaining a representative sample than by meeting minimum sample size requirements. For example, a representative sample may be generated by taking the same number of samples per row in the ice bed. However, when performing stratifiedsampling, it is noted that minimum sample size criteria must be met when the focus is on a sub-population of the ice bed.

The initial sample group can be expanded as necessary (such as when the calculated total mean mass of the ice bed is below the minimum required total mean ice mass); however, the initial sample population must be retained and the additional samples added to build the sample group as follows:

n. = initial sample group nb = expanded sample group = ne+n, n, = additional samples taken Note that the initial sample group is not discarded; rather, it becomes an element of the expanded sample group. This concept is based on Stein's Procedure in Chapter 8 of Reference 12.

TOPICAL REPORT ICUG-001, Revision 2 111.4 May 2003 DRAFT

Stratified Sampling Since, as shown in Section I, there is appreciable radial mass variation between some individual baskets in the ice bed population, stratifiedsampling is beneficial as it minimizes the risk that a small random sample will contain a disproportionate number of a minority group. Stratified sampling involves dividing the total population into groups of items that are expected to have similar characteristics (particularly the characteristic of interest), such as, in the case of the ice bed, mean basket mass and sublimation rates. As discussed in Section I, Radial Zones may be defined in the ice bed as groups of rows such that Zone A contains rows 7, 8, and 9; Zone B contains rows 4, 5, and 6, and Zone C contains rows 1, 2, and 3 (see Figures 3-3 and A-1) where each Radial Zone may even have different minimum design basis mass requirements. The total mass of ice in the ice bed with 95% confidence is obtained by summing the total masses of each stratified sub-population (or Radial Zone). The total mass of each Radial Zone is determined with 95% confidence by multiplying the mean calculated individual basket mass for the sample in that Zone by the total number of baskets in that Zone.

Figure 3-3. Illustrative Plan View of Ice Bed, Showing Three Radial Zone Groupings of Ice Baskets (648 baskets each) 12 13 11 14 10 15 9 16 8 17 7 18 6

5 4 21 2

2

/ ~~Zone A\

-~ ~Zn B LJ Zone C TOPICAL REPORT ICUG-001, Revision 2 III-5 May 2003 DRAFT

Assurance that the ice in the ice bed is both evenly distributed and the total ice mass meets a specified limit is provided by stratified sampling, since all regions (or stratified sub-populations of the ice bed) are equally represented and evaluated. Further, the baskets within a Radial Zone would have a fairly normal distribution, to which the sampling plan can be applied.

Examination of recent historical data from various ice condenser plants (reference Section 1)indicates that certain radial rows consistently sublimate at markedly different rates than others. The innermost crane wall rows sublimate at a higher rate than the outer rows as a function of their proximity to heat sources (Figure 3-4). Depending on ice bed and containment temperatures (and other characteristics unique to each plant), general radial sublimation rates will vary from plant to plant, but the overall trend is the same. Therefore, stratified sampling is applied to the generic case by grouping these Radial zones based on industry-wide historical sublimation and ice mass data.

Figure 3-4. Plan View of Containment Building, Showing Proximity of Steam Generator and Pressurizer Compartments to Ice Condenser Bays TOPICAL REPORT ICUG-O01, Revision 2 m-6 May 2003 DRAFT

It is also noted that when random sampling without replacement is used (where each basket in the sample can appear only once, with each basket in the total population having the same probability of being selected), the sample will generally result in the various regions of the ice bed being well represented.

The azimuthal (as opposed to radia) distribution of ice (see Figures 3-3 and 3-4) does not need to be verified via stratification if the overall azimuthal sublimation rate of the ice bed is not expected to vary significantly. As described in Section L historical industry and plant-specific data show that azimuthal variances would not preclude a random sample from being representative of the ice bed.

Alternate Mass Determination Methods To show compliance with the ice mass technical specification surveillance requirements, the mass of the individual sample ice baskets is typically determined by lifting the basket with a lifting rig and an attached scale or load cell. The accuracy of the scale has been treated conservatively in the past as a systematic bias and accounted for in as-left (pre-maintenance) ice mass surveillance requirement limits.

However, some baskets have a tendency to become stuck (i.e., frozen in place) as a result of surface ice accumulation, and cannot be physically lifted. To address this in the sampling plan, alternate mass determination methods will be utilized. Alternate mass determination methods are expected to have a lower accuracy than the lifting rig method, but will provide a reasonable assessment of ice mass when a sample selection is initially found to be stuck. As described in Section IL there are three primary methods designed by the industry to determine individual ice basket mass: direct lifting using a scale or load cell, software projection of the ice basket mass using basket mass histories and sublimation rates, and a visual inspection/estimation process. The uncertainty of a given method is a combination of the method's systematic bias and random error. As discussed previously, the individual observed ice basket masses are adjusted for systematic bias before the mass value is used as an input to Equations 3.2. Approximate measurement random error for these three methods are recalled from Section II (adjusted for clarity):

Table 3-1. Ice Basket Mass Measurement Random Error r Mass Determination Method : Measurement Random Error (See Notes)

Manual Lifting Using Scale A 15 lb Trending Using ICEMAN1m Code

• 40 lb Visual Inspection

• 300 lb Notes:

1. The error given for these measurement techniques is approximate and listed for reference only. Plant-specific maintenance procedures will qualify the processes used.

2. The error values shown may not be equal to the one-sigma random error defined in Equation 3.2.

Plant-specific procedures will determine the appropriate value to use in Equation 3.2 and will normally represent about two standard deviations for any alternate mass determination method.

The effect of varying uncertainty when utilizing different mass determination methods can be accounted for in several ways:

1. The measurement random error can be conservatively treated as a bias and either deducted from the measured basket mass or added to the minimum required total mean mass (as was done historically).

2. The error of the mean can be utilized, which more realistically deals with the error. The variation of each measurement made consists of a combination of the actual variation in the population (i.e.,

TOPICAL REPORT ICUG-001, Revision 2 111-7 May 2003 DRAFT

the variationof the process) and the variation due to the measurement error (i.e., the variation of the measurement). In this approach, the error of the measurement technique propagates to the standard error of the mean (see Equation 3.2). As discussed previously, the effect of errors associated with ice mass determination is conservatively accounted for in Equation 3.2, since the equation assumes the standard deviation of the sample, s, is the true value. The value of s calculated, however, will very likely be greater (more conservative) because it has some contribution from the measurement error.

An example calculation using a representative ice basket mass distribution illustrates the effect of different mass determination methods on the total ice mass estimated by the statistical sampling plan for a typical ice bed Radial Zone (Zone A is considered for this example). The results are provided in Table 3-2, which illustrates:

• The effect of using the visual inspection mass determination method.

• The effect of using an expanded sample.

Table 3-2. Illustration of Effects of Altemate Mass Determination Methods and Expanded Sample - Radial Zone A

-r 0 70 0 -Case -:  : ~  : Change In Total Ice

.____________.___________.____________ Mass for Radial Zone All 30 sample baskets lifted with scale Base Individual ice basket mass determined by combination of mass determination methods (50% -19443 lb lifted with scale, 50% estimated visually)

Individual ice basket mass determined by visual method only:

30-basket sample (initial) -33724 lb

. ...... .......... ........ . b..............

y 30 .........................................

60-basket sample (expanded by 30) -12123 lb.

90-basket sample (expanded by 60) -2807 lb Note: This illustration assumes the mean mass of the sample baskets remains constant and the standard deviation of the sample(s) remains constant at s = s30 = s60 = s,0 = 184.5 lb (which is taken from the example calculation in Appendix A for a stratified sample size of 30 ice baskets in Zone A). Therefore, the number of samples and the percentage of the sample masses determined visually vary in this example. In reality, the expanded sample mean and standard deviation would differ from the initial sample mean and standard deviation.

TOPICAL REPORT ICUG-001, Revision 2 H1-8 May 2003 DRAFT

Altemate Basket Selection Strateav In the event that an ice basket selected for the initial sample is found to be obstructed or stuck in such a way that its mass cannot be determined by any available method, an alternate basket can be selected as a direct replacement for the obstructed basket in the sample group. An alternate selection will not affect the validity of the sample, provided that it is chosen randomly from the same Radial Zone and in the same vicinity as the initial selection. In addition, there must be limits placed on the repeat use of alternate selections to ensure that the same alternate basket is not always selected as a result of all other candidate baskets being obstructed. To be a representative replacement for the initial sample basket, the alternate selection must meet the following criteria:

1. The alternate sample selection must be from the same Radial Zone (e.g., Zone A, B, or C) as the initial sample selection.

2. The alternate sample selection must be from the same Bay as the initial sample selection.

3. An alternate selection cannot be a repeated selection in the current surveillance, and cannot have been used as an analyzed alternate selection in the three most recent previous surveillances that included the Bay-Zone involved.

As discussed in Section I, this approach is reasonable since ice baskets in the same Radial Zone have similar mean mass characteristics and therefore may be considered statistically similar for ice mass sampling purposes. It further notes that maintenance of the ice bed using AIDM methodology ensures that extreme differences in ice basket masses across a given Radial Zone will not be realized. Therefore, baskets within the same Radial Zone will be considered representative of one another. Also, note that baskets within the same Radial Zone have the same probability of being selected as a primary sample.

Though the probability of being selected as an alternate is different than the probability of being selected as a primary, the 95% confidence interval for the Radial Zone is not invalidated. Restricting the baskets from which an alternate may be selected to the same Bay, and restricting the frequency with which a basket may serve as an alternate, reduces the likelihood that a large region of obstructed baskets is excluded from the surveillance sample. This approach for selecting alternate baskets also prevents regions of the ice bed (such as problematic radial rows) from being systematically eliminated from the parent population.

Applications of Sampling Plan Figure 3-5 provides the error of the mean (see Equation 3.2) as a function of the fraction of the sample basket population measured by the visual inspection method for various sample sizes, assuming a standard deviation of 100 lb (which was selected considering typical values seen in ice condenser basket populations). The remaining fraction of the sample is measured by the lifting rig/scale method. These two methods were chosen because they envelope the error resulting from the ICEMAN'h prediction, and thus provide conservative results. Note that while the error for visual inspection methodology is relatively large (+/-300 lb), its effect on the error of the mean relative to typical mean ice basket masses (between 1000 and 1500 lb of ice), is small. However, if the calculated mean ice basket mass of the sample propagates to a value near the minimum required total mean ice basket mass for a Radial Zone, the mass determination error and/or the sample size can make a significant difference.

TOPICAL REPORT ICUG-001, Revision 2 111-9 May 2003 DRAFT

Figure 3-5. Effect of Visual Estimation Measurement Error on the Error of the Mean for Various Sample Sizes II Sample Size

- - 72

-108

'144 0 0.i 0.2 0.3 0.4 0.8 0.6 0.7 0.8 0.0 I

- Fraction of Sample Measured Using Vsual M*thod (3S0lb wrtor)

An example of the utilization of the ice mass statistical sampling plan is provided in Appendix A. The ice bed mean mass is determined for a hypothetical ice condenser plant as follows:

• Sample sizes of 36, 72, 90, 108 and 144, with each sample group containing the subset of the next smaller sample group. The sample group is provided in Table 34 and repeated in Appendix A.

Note that the basket mass values given in Table 3-4 and Appendix A are assumed to have already been adjusted for systematic bias.

• With and without stratified sampling (using three Radial Zones comprised of three sequential rows each).

• Various ice mass determination methods, assuming the values shown in Table 3-1 are equivalent to the one standard deviation random error (ai ).

• As-found (pre-maintenance) individual ice basket mass is used.

The actual total ice bed mass in the example is 2,485,268 lb as calculated by totaling the individual ice basket masses (determined using various methods). Note from Table 3-3 that this value is greater than all of the total ice bed masses calculated with 95% confidence from the sample group. The example demonstrates that the total ice bed mass with 95% confidence will generally increase (getting closer to the actual total ice bed mass) with increased sample size. However, as can be seen from the non-stratified mass for the 108-basket sample size, this is not always the case, depending on the individual ice mass of the samples selected. Also, non-stratified sampling will result in a higher total mass than stratified sampling. This is due to the smaller sample size used in the calculation of the mean ice mass for the stratified group.

TOPICAL REPORT ICUG-001, Revision 2 III-10 May 2003 DRAFT

The selection of sample size, sample configuration, and mass determination methods depends largely on how much errorofthe mean can be tolerated while still meeting specific technical specification criteria.

Table 3-3. Ice Bed Masses from Sample Group Sample Size S eType of Sampling -5%

Ice Bed Mass at TotalConfidence Not Stratified 2,447,985 lb 36 :

36 Stratified 'hetC I) 2,372,078 lb Not Stratified 2,463,030 lb 72 Stratified G 2,410,530 lb Not Stratified 2,456,726 lb Stratified (N 2,409,810 lb Not Stratified 2,458,818 lb 108 Stratified 8 2,417,634 lb

-Not^,Stratified 144 f - - :2,475,670 lb Stratifieda U' 2,440,296 lb Notes:

(1) Uses three Radial Zones with three sequential rows in each Zone. The same number of samples are taken from each Zone.

(2) Actual total ice bed mass is 2,485,268 lb as determined by totaling the individual ice basket masses (which were determined using various methods). See Appendix A for the parent population ice basket data, which was based on basket mass data from the seven units of record.

TOPICAL REPORT ICUG-001, Revision 2 II-l-May 2003 DRAFI

Table 3-4. Ice Mass Sample Group Basiet Number Row Column Bay Radial Zone Mass Method 124 1 7 14 C 1350 Visual 158 1 5 18 C 1325 Visual 127 1 1 15 C 1532 Scale 26 1 8 03 C 1050 Visual 92 1 2 11 C 1322 Visual 178 1 7 20 C 1538 ICEMAN1 m 86 1 5 10 C 1678 ICEMANm 163 1 1 19 C 1101 Visual 105 1 6 12 C 1356 Scale 171 1 9 19 C 1278 Visual 195 1 6 22 C 1500 Visual 73 1 1 09 C 1365 Visual 29 1 2 04 C 1884 Scale 14 1 5 02 C 1145 Visual 22 1 4 03 C 1300 Visual 149 1 5 17 C 1400 Visual 265 2 4 06 C 1500 Visual 334 2 1 14 C 1468 ICEMANrM 337 2 4 14 C 1433 ICEMANrm 425 2 2 24 C 1198 Scale 386 2 8 19 C 1412 Visual 264 2 3 06 C 1643 ICEMAN Tm 221 2 5 01 C 1374 Scale 322 2 7 12 C 1485 Scale 364 2 4 17 C 1283 Visual 226 2 1 02 C 1100 Visual 391 2 4 20 C 1383 Scale 379 2 1 19 C 1199 Visual 310 2 4 11 C 1356 Visual 292 2 4 09 C 1245 Visual 332 2 8 13 C 1436 Scale 287 2 8 08 C 1347 Scale 478 3 1 06 C 1516 ICEMAN Tm 492 3 6 07 C 1478 Scale 628 3 7 22 C 1413 Scale 487 3 1 07 C 1450 Scale 463 3 4 04 C 1426 Scale 456 3 6 03 C 1506 Scale 605 3 2 20 C 1421 Scale 450 3 9 02 C 1329 Scale 638 3 8 23 C 1458 Scale 542 3 2 13 C 1334 Scale 620 3 8 21 C 1367 Scale 501 3 6 08 C 1392 Scale 625 3 4 22 C 1503 Scale 464 3 5 04 C 1415 Scale TOPICAL REPORT ICUG-001, Revision 2 111-12 May 2003 DRAFT

Table 3-4. Ice Mass Sample Group (continued)

Basket Number Row Column Bay Radial Zone Mass Method 519 3 6 10 C 1438 Scale 534 3 3 12 C 1425 Scale 811 4 1 19 B 1411 Scale 777 4 3 15 B 1218 Scale 823 4 4 20 B 1243 Scale 756 4 9 12 B 1298 Scale 842 4 5 22 B 1345 Scale 688 4 4 05 B 1264 Scale 725 4 5 09 B 1255 Scale 651 4 3 01 B 1306 Scale 702 4 9 06 B 1291 Scale 746 4 8 I B 1397 Scale 714 4 3 08 B 1207 Scale 788 4 5 16 B 1247 Scale 805 4 4 18 B 1211 Scale 650 4 2 01 B 1320 Scale 778 4 4 15 B 1202 Scale 706 4 4 07 B 1344 Scale 883 5 1 03 B 1366 Scale 867 5 3 01 B 1248 Scale 935 5 8 08 B 1195 Scale 994 5 4 15 B 1265 Scale 936 5 9 08 B 1326 Scale 975 5 3 13 B 1329 Scale 990. 5 9 14 B 1233 Visual 934 5 7 08 B 1170 Scale 917 5 8 06 B 1233 Scale 1022 5 5 18 B 1244 Scale 952 5 7 10 B 1305 Scale 887 5 5 03 B 1314 Scale 987 5 6 14 B 1246 Scale 898 5 7 04 B 1190 Scale 939 5 3 09 B 1185 Scale 1059 5 6 22 B 1207 Scale 1183 6 4 12 B 1258 Scale 1244 6 2 19 B 1230 Scale 1146 6 3 08 B 1159 Scale 1181 6 2 12 B 1225 Scale 1267 6 7 21 B 1110 Scale 1258 6 7 20 B 1192 Scale 1136 6 2 07 B 1183 Scale 1167 6 6 10 B 1363 Scale 1132 6 7 06 B 1338 Scale 1173 6 3 11 B 1212 Scale 1121 6 5 05 B 1218 Scale 1267 6 7 21 B 1110 Scale TOPICAL REPORT ICUG-001, Revision 2 I-13 May 2003 DRAFT

Table 3-4. Ice Mass Sample Group (continued)

BasketlNumber -Row' ;Column Bay Radial Zone Mass Method 1256 6 5 20 B 1149 Scale 1175 6 5 11 B 1288 Scale 1163 6 2 10 B 1198 Scale 1273 6 4 22 B 1342 Scale 1490 7 5 22 A 1383 Visual 1510 7 7 24 A 1292 Scale 1342 7 1 06 A 1277 Visual 1487 7 2 22 A 1216 Scale 1397 7 2 12 A 1267 Visual 1378 7 1 10 A 1267 Visual 1498 7 4 23 A 1284 Scale 1436 7 5 16 A 1172 Visual 1368 7 9 08 A 1278 Visual 1301 7 5 01 A 1311 Scale 1371 7 3 09 A 1193 Scale 1506 7 3 24 A 1130 Scale 1323 7 9 03 A 1130 Scale 1466 7 8 19 A 1209 Visual 14 A 1739 ICEMAN' m 1421 7 8 1367 7 8 08 A 1445 Visual 1604 8 2 11 A 1497 Visual 1625 8 5 13 A 1362 Visual 1709 8 8 22 A 1449 Scale 1664 8 8 17 A 1406 Visual 1536 8 6 03- A 904 Visual 1571 8 5 07 A 1358 Visual 1528 8 7 02 A 838 Scale 1660 8 4 17 A 1378 Visual 1520 8 8 01 A 770 Scale 1636 8 7 14 A 1330 Scale 1650 8 3 16 A 1202 Scale 1514 8 2 01 A 1429 Visual 1634 8 5 14 A 1181 Visual 1519 8 7 01 A 1090 Scale 1606 8 4 11 A 1376 Visual 1594 8 1 10 A 1240 Scale 1803 9 3 09 A 1286 Scale 1909 9 1 21 A 1243 Visual 1767 9 3 05 A 1367 Visual 1743 9 6 02 A 938 Visual 1802 9 2 09 A 1121 Visual 1731 9 3 01 A 1536 Visual 1934 9 8 23 A 1159 Visual 1886 9 5 18 A 1434 Visual 1939 9 4 24 A 1349 Visual 1932 9 6 23 A 1297 Visual TOPICAL REPORT ICUG-001, Revision 2 111-14 May 2003 DRAFT

Table 3-4. Ice Mass Sample Group (continued)

-B6as-ke-tWrfi .-Row - Column Bay Radial Zone Mass Method 1846 9 1 14 A 1291 Visual 1757 9 2 04 A 1230 Scale 1875 9 3 17 A 1414 Visual 1905 9 6 20 A 902 Scale 1799 9 8 08 A 1448 Visual 1775 9 2 06 A 1500 Visual Summary Based on the statistical sampling plan discussion and the evaluations of applications of the plan, the recommendations for the Ice Mass Technical Specification Statistical Sampling Plan are as shown in Table 3-5.

Table 3-5. Ice Mass Sampling Plan Recommendations Recommendation Basis

1. Perform stratified sampling using defined Stratified sampling allows sub-populations to be Radial Zones, with each zone containing defined and results in conservative estimates of rows of ice baskets that exhibit similar total ice mass. The evaluations in Section I show characteristics. that ice baskets within Radial Zones A, B, and C (Figure 3-3) have similar mean mass characteristics.

2. Use at least 30 ice baskets in the initial As shown in Figure 3-2, 30 samples results in a sample for each Radial Zone. reasonable value for the errorofthe mean for the sample (i.e., it is at the "knee" in the curve.)

3. If the minimum ice mass requirement in a The approach is consistent with the sampling plan Radial Zone cannot be met with the initial methodology and the expanded sample will 30-basket sample, expand the sample in the provide a reduction in errorof the mean as Radial Zone as necessary (including the determined by Equation 3.2.

original 30 baskets).

4. l the mass cannot be determined for a As discussed in Section I, due to similar mean selected sample basket using any available mass, baskets from the same Radial Zone may be method, randomly select an alternate basket considered representative of one another for the from the vicinity of the initial selection as a purposes of sampling. AIMM methodology direct replacement in the sample. ensures that extreme differences in basket masses within a Radial Zone will not occur. By also limiting the population of qualified alternates to the same Bay as the initial selection and limiting the frequency with which a basket can serve as an alternate, the likelihood that a large region of obstructed baskets will be excluded from the surveillance sample over time will be reduced.

TOPICAL REPORT ICUG-001, Revision 2 111-15 May 2003 DRAFT

References

1. USNRC Safety Evaluation Report Related to Operation of Donald C. Cook Nuclear Plant Unit 1, Supplement 5, January 1976.

2. USNRC Safety Evaluation Supporting Amendment 18 to License DPR-58 (D.C. Cook), February 16, 1977.

3. AEP Corporation, "D.C. Cook Nuclear Plant Unit No. 1 - Long Term Evaluation of the Ice Condenser System - Results of the December 1974 Initial Ice Weighing Program," December 4, 1975.

4. AEP Corporation, "D.C. Cook Nuclear Plant Unit No. I - Long Term Evaluation of Ice Condenser System - Results of the March 1975 Ice Weighing Program," June, 1975.

5. AEP Corporation, "D.C. Cook Nuclear Plant Unit No. 1 - Long Term Evaluation of the Ice Condenser System - Results of the July 1975 and October 1975 Ice Weighing Program," December 9, 1975.

6. AEP Corporation, "D.C. Cook Nuclear Plant Unit No. I - Long Term Evaluation of the Ice Condenser System - Results of the January 1976 and April 1976 Ice Weighing Programs," July 30, 1976.

7. AEP Corporation, "D.C. Cook Nuclear Plant Unit No. 1 - Long Term Evaluation of the Ice Condenser System - Results of the July 1976 and September 1976 Ice Weighing Programs," October 1, 1976.

8. Metcalfe, Andrew W., "Statistics in Engineering - A Practical Approach," Chapman & Hall, Copyright 1994.

9. Witte, Robert S., "Statistics," Holt, Rinehart and Winston, Copyright 1980.

10. ANSI Standard N15.15-1974, "Assessment of the Assumption of Normality (Employing Individual Observed Values)."

11. NUREG/CR-4604, "Statistical Methods for Nuclear Material Management," December 1988.

12. NUREG-1475, "Applying Statistics," January 1995.

13. TID-26298, Jaech, John L., "Statistical Methods in Nuclear Material Control," December 1973.

14. Duke Energy Corp., McGuire Nuclear Station Final Safety Analysis Report, Revision 10/14/00, Section 6.2.1.1.3, "Loss of Coolant Accident Design Evaluation."

15. Duke Energy Corp., Catawba Nuclear Station Final Safety Analysis Report, Revision 4/8/00, Section 6.2.1.1.3, "Loss of Coolant Accident Design Evaluation."

16. Tennessee Valley Authority, Sequoyah Nuclear Plant Final Safety Analysis Report, Revision 5/4/98 (Rev. 14), Section 6.2.1.3.4, "Containment Pressure Transient - Long Term Analysis".

17. Tennessee Valley Authority, Watts Bar Nuclear Plant Final Safety Analysis Report, Amendment 2, Section 6.2.1, "Containment Functional Design".

TOPICAL REPORT ICUG-001, Revision 2 R-1 May 2003 DRAFT

18. American Electric Power Co., Donald C. Cook Nuclear Plant Final Safety Analysis Report, Revision 17.0, Section 5.3, "Ice Condenser".

19. ICUG Response to NRC Request for Additional Information, R.S Lytton letter to NRC dated June 12, 2002 (w/enclosure).

20. ICUG Response to NRC Request for Additional Information, R.S Lytton letter to NRC dated October 10, 2002 (w/enclosure).

21. ICUG Response to NRC Request for Additional Information, R.S Lytton letter to NRC dated October 22, 2002 (w/enclosures).

22. ICUG Response to NRC Request for Additional Information, R.S. Lytton letter to NRC dated November 26, 2002 (w/enclosures).

23. Everhart, Jerry, DeterminingMass Measurement Uncertainty, January 1997.

24. Abernathy, R.B., et al, and Thompson, Jr., J.W., Measurement UncertaintyHandbook, January 1980.

25. McClave, James T., and Dietrich, Frank H., A FirstCoursein Statistics,third edition, copyright 1989.

26. Eisenhart, C., Expression of Uncertainties of FinalResults, PrecisionMeasurement and Calibration, NBS Handbook 91, Vol. , February 1969.

27. USNRC Draft Safety Evaluation for Ice Condenser Utility Group Topical Report No. ICUG-001, Revision 0: Application of the Active Ice Mass Management Concept to the Ice CondenserIce Mass Technical Specification, dated May 6, 2003 (w/enclosure).

TOPICAL REPORT ICUG-001, Revision 2 R-2 May 2003 DRAFT

Appendix A

• Figure A-1. Typical Ice Bed Arrangement and Identification

• Figure A-2. Typical Bay Map and Basket Identification

• Table A-i. Example Ice Bed Data

• Table A-2. Ice Mass Sample Group

• Table A-3. Example Calculations

• Original WOG Standard Technical Specification - Ice Bed TOPICAL REPORT ICUG-001, Revision 2 A-1 May 2003 DRAFT

Figure A-1. Typical Bay Arrangement and Identification 12 . 13 11 10 15 9

8 1 7

6 1!

5 2(

3 1

TOPICAL REPORT ICUG-001, Revision 2 A-2 May 2003 DRAFT

Figure A-2. Typical Bay Map and Basket Identification Containment Wall Crane Wall Basket ID is Column - Row TOPICAL REPORT ICUG-001, Revision 2 A-3 May 2003 DRAFT

Table A-1. Example Ice Bed Data FOR REFERENCE ONLY (Parent population for Section III example)

TOPICAL REPORT ICUG-001, Revision 2 A4 May 2003 DRAFT

Basket ID R ow, Basket As-Found ICEMAN' VISUAL Mass to Use Method Number Mass Projected Estlmated (Ib) Used

( b) Mass (lb) Mass (lb) 2-01-1-1 1 1 Frozen 1150 1150 Visual 2-01-1-2 1 2 Frozen 1200 1200 Visual 2-01-1-3 1 3 Frozen 1479 . 1479 ICEMANT 2-01-1-4 1 4 1328 1201 1328 Scale 2-01-1-5 1 5 1290 1290 Scale 2-01-1-6 1 6 909 1173 909 Scale 2-01-1-7 1 7 860 1183 860 Scale 2-01-1-8 1 8 680 1390 680 Scale 2-01-1-9 1 9 545 938 545 Scale 2-02-1-1 1 10 Frozen 1040 1040 Visual 2-02-1-2 1 11 Frozen 976 976 Visual 2-02-1-3 1 12 Frozen 1565 1565 ICEMANTM 2-02-1-4 1 13 Frozen 1619 1619 ICEMANTM 2-02-1-5 1 14 Frozen 1145 1145 Visual 2-02-1-6 1 15 Frozen 1200 1200 Visual 2-02-1-7 1 _ 16 1233 1692 1233 Scale 2-02-1-8 1 17 Frozen 1534 1534 ICEMANTM 2-02-1-9 1 18 Frozen 1755 175 5 ICEMANT 2-03-1-1 1 19 Frozen 1005 1005 Visual 2-03-1-2 1 20 Frozen 1582 15 82 ICEMAN 2-03-1-3 1 21 Frozen 1400 1400isual 2-03-1-4 1 22 Frozen 1300 1300 Visual 2-03-1-5 1 23 Frozen 1100 _1_00 Visual 2-03-1-6 1 24 Frozen - _1200 1200 Visual 2-03-1-7 1 25 Frozen 1350 1350 Visual 2-03-1-8 1 . 26 Frozen 1050 1050 Visual 2-03-1-9 1 27 Frozen 11_20 11_20 Visual 2-04-1-1 1 28 Frozen 1034 1034 Visual 2-04-1-2 1 29 1884 1739 1884 Scale 2-04-1-3 1 30 Frozen 1400 1400 Visual 2-04-1-4 1 31 Frozen 1376 1376 Visual 2-04-1-5 1 32 Frozen 1256 1256 Visual 2-04-1-6 1 33 Frozen 1234 1234 Visual 2-04-1-7 1 34 Frozen 1300 1300 Visual 2-04-1-8 1 35 Frozen 1006 1006 Visual 2-04-1-9 1 ____ 36 Frozen ____I100Viua 2-05-1-1 1 37 Frozen 1104 1104 Visual 2-05-1-2 1 38 1884 1884 Scale 2-05-1-3 1 39 1588 1588 Scale 2-05-1-4 1 40 Frozen 1301 1301 Visual 2-05-1-5 1 41 Frozen 1178 1178 Visual 2-05-1-6 1 42 Frozen 1256 1256 Visual 2-05-1-7 1 43 Frozen 1345 1345 Visual 2-05-1-8 1 44 Frozen 1527 1527 ICEMANTM 2-05-1-9 1 45 Frozen 1234 1234 Visual 2-06-1-1 1 46 Frozen 1123 1123 Visual 2-061-2 1 47 Frozen 1056 1056 Visual 2-06-1-3 1 48 Frozen 1087 1087 Visual 2-06-1-4 1 49 Frozen ______ 1400__ 14001Visual TOPICAL REPORT ICUG-001, Revision 2 A-S May 2003 DRAFT

2-06-1-5 1 50 Frozenl 1450 1450 Visual 2-061-6 1 51 Frozen 1200 1200 Visual 2406-1-7 1 52 Frozen 1300 1300 Visual 2-0-1-4 1 53 Frozen 1256 1256 Visual 2-06-1-9 1 54 Frozen 1398 1398 Visual 2-07-1-1 1 55 Frozen 1304 1304 Visual 2-07-1-2 1 56 Frozen 1298 1298 Visual 2-07-1-3 1 57 Frozen 1259 1259 Visual 2-07-1-4 1 58 Frozen 1199 1199 Visual 2-07-1-5 1 59 Frozen 1245 1245 Visual 2-07-1-6 1 60 Frozen 1300 1300 Visual 2-07-1-7 1 61 Frozen 1325 1325 Visual 2-07-1-8 1 62 Frozen 1523 1523 ICEMANT 2-07-1-9 1 63 Frozen  : 1340 1340 Visual 2-08-1-1 1 64 1382 . 1382 Scale 2-08-1-2 1 65 1200 1218 1200 Scale 2-08-1-3 1 66 1100 1155 1100 Scale 2-08-1-4 1 67 1214 _ _ _ __ 1214 Scale 2-08-1-5 1 68 890 890 Scale 2-08-1-6 1 69 1202 1202 Scale 2-08-1-7 1 70 1326 1326 Scale 2-08-1-8 1 71 1251 1251 Scale 2-08-1-9 1 72 Frozen _____1456 1456 Visual 2-09-1-1 1 73 Frozen 1365 1365 Visual 2-09-1-2 1 74 Frozen 1367 1367 Visual 2-09-1-3 1 75 Frozen _ 1298 1298 Visual 2-09-1-4 1 76 Frozen 1200 1200 Visual 2-09-1-5 1 77 Frozen _ 1378 1378 Visual 2-09-1-6 1 78 Frozen lOC1000 1000 Visual 2-09-1-7 1 79 Frozen 1562 1562 ICEMANTM 2-09-1-8 1 80 1609 1679 1609 Scale 2-09-1-9 1 81 1427 1643 1427 Scale 2-10-1-1 1 82 Frozen 1245 1245 Visual 2-10-1-2 1 83 1704 1665 1704 Scale 2-10-1-3 1 84 1558 1617 1558 Scale 2-10-1-4 1 85 1487 1699 1487 Scale 2-10-1-5 1 86 Frozen 1678 1678 ICEMANTM 2-10-1-6 1 87 1504 1449 1504 Scale 2-10-1-7 1 88 Frozen 1640 1640 ICEMANT' 2-10-1-8 1 89 Frozen 1669 1669 ICEMANTM 2-10-1-9 1 .... 90 Frozen 1456 1456 Visual 2-11-1-1 1 91 Frozen :1400 1400 Visual 2-11-1-2 1 92 Frozen 1322 1322 Visual 2-11-1-3 1 93 Frozen 1256 1256 Visual 2-11-1-4 1 94 Frozen 1205 1205 Visual 2-11-1-5 1 95 Frozen 1156 1156 Visual 2-11-1-6 1 96 Frozen 987 987 Visual 2-11-1-7 1 97 Frozen 1457 __ __ 1457 ICEMAN TM 2-11-1-8 1 _ 98 Frozen 945 945 Visual 2-11-1-9 1 199 Frozen 1467 1467 Visual 2-12-1-1 1 1100 Frozen 1500C 1500 Visual 2-12-1-2 1_101 1445 1492 1 1445 Scale TOPICAL REPORT ICUG-001, Revision 2 A-6 May 2003 DRAFT

2-12-1-3 1 102 Frozen 1452 1452 ICEMANTM 2-12-1-4 1 103 Frozen 1300 1300 Visual 2-12-1-5 1 104 Frozen 1117 1117 Visual J

2-12-1-6 1 105 1356 1556 1356 Scale 2-12-1-7 1 106 Frozen 1302 1302 Visual 2-12-1-8 1 107 Frozen 1101 1101 Visual 2-12-1-9 1 108 Frozen 1034 1034 Visual 2-13-1-1 1 109 Frozen 1001 1001 Visual 2-13-1-2 1 110 1534 1514 1534 Scale 2-13-1-3 1 111 1300 1206 1300 Scale 2-13-1-4 1 112 1340 1326 1340 Scale 2-13-1-5 1 113 Frozen 1234 1234 Visual 2-13-1-6 1 114 Frozen 1002 1002 Visual 2-13-1-7 1 115 Frozen 1464 1464 ICEMANTM 2-13-1-8 1 116 Frozen 1156 1156 Visual 2-13-1-9 1 117 Frozen 1400 1400 Visual 2-14-1-1 1 118 1485 1485 Scale 2-14-1-2 1 119 1399 1471 1399 Scale 2-14-1-3 1 120 1389 1344 1389 Scale 2-14-1-4 1 121 1302 1313 1302 Scale 2-14-1-5 1 122 Frozen 1250 1250 Visual 2-14-1-6 1 123 Frozen 1200 1200 Visual 2-14-1-7 1 124 Frozen 1350 1350 Visual 2-14-1-8 1 125 Frozen 1000 1000 Visual 2-14-1-9 1 126 Frozen 1400 1400 Visual 2-15-1-1 1 127 1532 1662 1532 Scale 2-15-1-2 1 128 1632 1690 1632 Scale 2-15-1-3 1 129 1579 1622 1579 Scale 2-15-1-4 1 130 1473 1402 1473 Scale 2-15-1-S 1 131 1455 1378 1455 Scale 2-15-1-6 1 132 1437 1426 143 Scale 2-15-1-7 1 133 1416 1424 1416 Scale 2-15-1-8 1 134 1509 1538 1509 Scale 2-15-1-9 1 135 1498 1475 1498 Scale 2-16-1-1 1 136 Frozen _ _ _1221 ____1221 Visual 2-16-1-2 1 137 Frozen 1574 1574 ICEMANTm 2-16-1-3 1 138 Frozen 1256 1256 Visual 2-16-1-4 1 139 Frozen 1302 _ _1302 Visual 2-16-1-S 1 140 Frozen 1102 1102 Visual 2-16-1-6 1 141 Frozen 1267 1267 Visual 2-16-1-7 1 142 Frozen 1410 14_1C Visual 2-16-1-8 1 143 1620 1768 1620 Scale 2-16-1-9 1 144 Frozen 1342 1342 Visual 2-17-1-1 1 145 Frozen 1266 1266 Visual 2-17-1-2 1 146 Frozen 1234 1234 Visual 2-17-1-3 1 147 Frozen 1256 1256 Visual 2-17-1-4 1 148 Frozen 1187 1187 Visual 2-17-1-5 1 149 Frozen 1400 1400 Visual 2-17-1-6 1 150 Frozen ____1205 1205 Visual 2-17-1-7 1 _151 Frozen 1398 1398 ICEMANTM 2-17-1-8 1 152 Frozen 1473 1473 ICEMANTM 2-17-1-9 1 153 Frozen 12331 1233 Visuali___

TOPICAL REPORT ICUG-001, Revision 2 A-7 May 2003 DRAFT

2-18-1-1 1 154 Frozen 1475 1475 Visual 2-18-1-2 1 155 Frozen 1098 1098 Visual 2-18-1-3 1 156 1518 1591 1518 Scale 2-18-1-4 1 157 Frozen 1300 1300 Visal 2-18-1-5 1 158 Frozen 1325 1325 Visual 2-18-1-6 1 159 Frozen _ 1203 1203 Visual 2-18-1-7 1 160 Frozen 1175 1175 Visual 2-18-1-8 1 161 Frozen 1434 1434 Visual 2-18-1-9 162 - Frozen 1400 1400 Visual 2-19-1-1 1 163 Frozen 1101 1101 Visual 2-19-1-2 1 164 1600 1531 1600 Scale 2-19-1-3 1 165 Frozen 1236 1236 Visual 2-19-1-4 1_166 Frozen 1056 1056 Visual 2-19-1-5 1_167 Frozen1500 1500 Visual 2-19-1-6 1 168 Frozen 1456 1456 Visual 2-19-1-7 1 169 Frozen 1300 1300 Visual 2-19-1-8 1 170 Frozen 1757 1757 ICEMAN'hI 2-19-1-9 1 171 _Frozen 1278 1278 Visual 2-20-1-1 1 172 Frozen 1334 1334 Visual 2-20-1-2 1 173 1518 1485 1518 Scale 2-20-1-3 1 174 1500 1296 1500 Scale 2-20-1-4 1 175 Frozen 1233 1233 Visual 2-20-1-5 1176 Frozen _ _ _ 1544 1544 ICEMAN'm 2-20-1-6 1 177 Frozen 1306 1306 ICEMAN'm 2-20-1-7 1 178 Frozen 1538 1538 ICEMANTM 2-20 1 179 Frozen 1590 1590 ICEMAUN 2-20-1-9 1 180 Frozen 1640 1640 ICEMANl 2-21-1-1 1 1 81 1256 1344 1256 Scae 2-21-1-2 1182 1251 1401 1251 Scale 2-21-1-3 1183 1156 1172 1156 Scale 2-21-14 1 14 1172 991 -1172 Scae 2-21-1-5 1 18 897 1097 897 Scale 2-21-1-6 1 186 1158 1144 1158 Scae 2-21-1-7 1 187 1512 1507 1512 Scae 2-21-1-8 1 188 Frozen 1432 1432 ICEMAN' 2-21-1-9 1 1 89 Frozen - 1256 1256 Viual 2-22-1-1 1 190 Frozen 1234 1234 Viual 2-22-1-2 1 191 Frozen 1075 1075 Visal 2-22-1-3 1 192 Frozen 1104 1104 Viual 2-22-14 1 193 -Frozen 1189 1189 Visual 2-22-1-5 1 194 Frozen 1400 1400 Visual 2-22-1-6 1 195 Frozen 1500 S00 Visual 2-22-1-7 1 196 Frozen 1614 1614 ICEMAN 2-22-1-8 1 197 Frozen 1536 1536 Visual 2-22-1-9 1 198 1347 1347 Scale 2-23-1-1 1 199 Frozen 1500 IS00 Visual 2-23-1-2 1 200 Frozen 1467 1467 Visual 2-23-1-3 1 201 Frozen 1536 1536 ICEMlAN 2-23-14 1 202 Frozen 1523 1523 ICENIA 2-23-1-S 1 203 Frozen 1421 1421 ICEMANTm 2-23-1-6 1 204 Frozen 1420 1420 Visual 2-23-1-7 1 205 Frozen , 1500 lS00__Vual TOPICAL REPORT ICUG-001, Revision 2 A-8 May 2003 DRAFT

2-23-1-8 1 206 Frozen l 1221 1221 Visual 2-23-1-9 1 207 Frozen ____-_1122 1122 Visual 2-24-1-1 1 208 1320 1371 1320 Scale 2-24-1-2 1 209 1150 1155 1150 Scale 2-24-1-3 1 210 1264 1190 1264 Scale 2-24-1-4 1 211 Frozen 1145 1145 Visual 2-24-1-5 1 212 Frozen _ 1278 1278 Visual 2-24-1-6 1 213 Frozen  : 1007 1007 Visual 2-24-1-7 1 214 Frozen 985 985 Visual 2-24-1-8 1 215 Frozen 1200 1200 Visual 2-24-1-9 1 216 Frozen 1365 1365 Visual 2-01-2-1 2 217 Frozen 1345 1345 Visual 2-01-2-2 2 218 Frozen 1202 1202 Visual 2-01-2-3 2 219 1388 1687 1388 Scale 2-01-2-4 2 220 1436 1211 1436 Scale 2-01-2-5 2 221 1374 1532 1374 Scale 2-01-2-6 2 222 Frozen 1245 1245 Visual 2-01-2-7 2 223 1002 1200 1002 Scale 2-01-2-8 2 224 1082 1186 1082 Scale 2-01-2-9 2 225 1180 1136 1180 Scale 2-02-2-1 2 226 Frozen 1100 1100 Visual 2-02-2-2 2 227 1357 1308 1357 Scale 2-02-2-3 2 228 1271 1266 1271 Scale 2-02-2-4 2 229 1305 1268 1305 Scale 2-02-2-5 2 230 1090 1214 1090 Scale 2-02-2-6 2 231 Frozen 1123 1123 Visual 2-02-2-7 2 232 1267 1286 1267 Scale 2-02-2-8 2 233 1371 1336 1371 Scale 2-02-2-9 2 234 1387 1355 1387 Scale 2-03-2-1 2 235 Frozen 1003 1003 Visual 2-03-2-2 2 236 1602 1491 1602 Scale 2-03-2-3 2 237 Frozen 1174 1174 Visual 2-03-2-4 2 238 Frozen 1009 1009 Visual 2-03-2-5 2 239 Frozen 1300 1300 Visual 2-03-2-6 2 240 Frozen 1477 1477 Visual 2-03-2-7 2 241 Frozen 1468 1468 Visual 2-03-2-8 2 242 Frozen 1512 1512 Visual 2-03-2-9 2 243 Frozen . 958 958 Visual 2-04-2-1 2 244 Frozen 1189 1189 Visual 2-04-2-2 2 245 1595 1628 1595 Scale 2404-2-3 2 246 Frozen 1484 1484 Visual 2-04-2-4 2 247 Frozen 1233 1233 Visual 2-04-2-5 2 248 Frozen 1528 1528 Visual 2-04-2-6 2 249 Frozen 1101 1101 Visual 2-04-2-7 2 250 Frozen 1135 1135 Visual 2-04-2-8 2 251 Frozen 1182 1182 Visual 2-04-2-9 2 252 Frozen 1620 1620 ICEMANTm 2-05-2-1 2 253 Frozen 1400 1400 Visual 2-05-2-2 2 254 1434 1434 1434 Scale 245-2-3 2 -255 1528 1461 1528 Scale 2-05-2-4 2 256 1439 1391 1 1439 Scale 2-05-2-5 2 1257 Frozen _ 1345 1345 Visual TOPICAL REPORT ICUG-001, Revision 2 A-9 May 2003 DRAFT

2-05-2-6 2 258 Frozen 1398 1398 Visual 2-05-2-7 2 259 1494 1457 1494 Scale 2-05-2-8 2 260 1396 1576 1396 Scale 2-05-2-9 2 261 1433 1438 _ 1433 Scale 2-06-2-1 2 262 Frozen 1467 1467 Visual 2-06-2-2 2 263 Frozen 1536 1536 Visual 2-06-2-3 2 264 Frozen 1643 _ 1643 ICEMANTm 2-06-2-4 2 265 Frozen 1500 1500 Visual 2-06-2-5 2 266 Frozen 1512 1512 Visual 2-06-2-6 2 267 Frozen 1434 1434 Visual 2-06-2-7 2 268 Frozen 1365 1365 Visual 2-06-2-8 2 269 Frozen 1599 _ _ 1599 ICEMANTm 2-06-2-9 2 270 Frozen 1200 1200 Visual 2-07-2-1 2 271 Frozen 1340 1340 Visual 2-07-2-2 2 272 Frozen 1134 1134 Visual 2-07-2-3 2 273 Frozen 1176 1176 Visual 2-07-2-4 2 274 Frozen 1186 _ 1186 ICEMANTm 2-07-2-5 2 275 Frozen 1204 1204 Visual 2-07-2-6 2 276 Frozen 1330 1330 Visual 2-07-2-7 2 277 1612 1538 1612 Scale 2-07-2-8 2 278 1540 1516 1540 Scale 2-07-2-9 2 279 Frozen 1480 1480 ICEMANIm 2-08-2-1 2 280 1437 1383 1437 Scale 2-08-2-2 2 281 1284 1267 1284 Scale 2-08-2-3 2 282 1193 1214 1193 Scale 2-08-2-4 2 283 1182 1182 Scale 2-08-2-5 2 284 1067 1067 Scale 2-08-2-6 2 285 1149 _ 1149 Scale 2-08-2-7 2 _ 286 1211 1252 1211 Scale 2-08-2-8 2 287 1347 1356 1347 Scale 2-08-2-9 2 288 1389 1422 1389 Scale 2-09-2-1 2 289 Frozen 1607 1607 ICEMANTm 2-09-2-2 2 290 1546 1634 1546 Scale 2-09-2-3 2 291 1600 1554 1600 Scale 2-09-2-4 2 292 Frozen 1245 1245 Visual 2-09-2-5 2 293 Frozenr 1400 1400 Visual 2-09-2-6 2 294 Frozen 1502 1502 Visual 2-09-2-7 2 295 1500 1560 1500 Scale 2-09-2-8 2 296 1465 1472 1465 Scale 2-09-2-9 2 297 1404 1593 1404 Scale 2-10-2-1 2 298 Frozen 1499 1499 Visual 2-10-2-2 2 299 1618 1607 1618 Scale 2-10-2-3 2 300 1472 1660 1472 Scale 2-10-2-4 2 301 1446 1440 1446 Scale 2-10-2-5 2 302 1270 1279 1270 Scale 2-10-2-6 2 303 1437 1473 1437 Scale 2-10-2-7 2 304 1583 1616 1583 Scale 2-10-2-8 2 . 305S1552 1556 1552 Scale 2-10-2-9 2 306 Frozenr 1345 1345 Visual 2-11-2-1 2307 Frozr 1288 1288 Visual 2-11-2-2 2308 1542 1542 Scale 2-11-2-3 2 309 Frozer 1378 1378 Visual TOPICAL REPORT ICUG-001, Revision 2 A-10 May 2003 DRAFT

2-11-2-4 2 310 Frozen 1356 1356 Visual 2-11-2-5 2 311 Frozen 1645 1645 Visual 2-11-2-6 2 312 Frozen 1233 1233 Visual 2-11-2-7 2 313 1590 1639 1590 Scale 2-11-2-8 2 314 1568 1605 1568 Scale 2-11-2-9 2 315 Frozen 1642  : 1642 ICEMANTM 2-12-2-1 2 316 Frozen 1445 1445 ICEMANTM 2-12-2-2 2 317 1542 1540 1542 Scale 2-12-2-3 2 318 Frozen 1645 1645 ICEMANTM 2-12-2-4 2 319 Frozen 1500 1500 Visual 2-12-2-5 2 320 Frozen 1400 1400 Visual 2-12-2-6 2 321 1507 1544 1507 Scale 2-12-2-7 2 322 1485 1567 1485 Scale 2-12-2-8 2 323 1555 1574 1555 Scale 2-12-2-9 2 324 Frozen 1305 1305 Visual 2-13-2-1 2 325 Frozen 1243 1243 Visual 2-13-2-2 2 326 1488 1533 1488 Scale 2-13-2-3 2 327 1476 1502 1476 Scale 2-13-2-4 2 328 1442 1515 = 1442 Scale 2-13-2-5 2 329 Frozen 1451 1451 ICEMANTm 2-13-2-6 2 330 1446 1506 1446 Scale 2-13-2-7 2 331 1442 1514 1442 Scale 2-13-2-8 2 332 1436 1462 1436 Scale 2-13-2-9 2 333 Frozen . 1259 1259 Visual 2-14-2-1 2 334 Frozen 1468 1468 ICEMANTM 2-14-2-2 2 335 1340 1359 1340 Scale 2-14-2-3 2 336 1233 1412 1233 Scale 2-14-2-4 2 337 Frozen 1433 1433 ICEMANTM 2-14-2-5 2 338 Frozen 1134 1134 Visual 2-14-2-6 2 339 1393 1393 Scale 2-14-2-7 2 340 1311 1297 1311 Scale 2-14-2-8 2 341 1340 1398 1340 Scale 2-14-2-9 2 342 1360 1360 Scale 2-15-2-1 2 343 1501 1620 1501 Scale 2-15-2-2 2 344 1471 1523 1471 Scale 2-15-2-3 2 345 1431 1471 1431 Scale 2-15-2-4 2 346 1366 1309 1366 Scale 2-15-2-5 2 347 1253 1279 1253 Scale 2-15-2-6 2 348 1327 1371 1327 Scale 2-15-2-7 2 349 1382 1381 1382 Scale 2-15-2-8 2 350 1486 1432 1486 Scale 2-15-2-9 2 351 1407 1290 1407 Scale 2-16-2-1 2 - 352 1573 1573 Scale 2-16-2-2 2 353 1495 1565 1495 Scale 2-16-2-3 2 354 1521 1521 Scale 2-16-2-4 2 355 1453 1453 Scale 2-16-2-5 2 356 Frozen 1504 1504 Visual 2-16-2-6 2 357 Frozen -1403 1403 Visual 2-16-2-7 2 358 1760 1760 Scale 2-16-2-8 2 359 1663 1509 1663 Scale 2-16-2-9 2 360 Frozen_ 1400 1400 Visual 2-17-2-1 2 361 Frozen_ 1348 1348 Visual TOPICAL REPORT ICUG-001, Revision 2 A-1 I May 2003 DRAFT

2-17-2-2 2 362 1714 1516 1714 Scale 2-17-2-3 2 363 Frozen 1328 1328 Visual 2-17-2-4 2 364 Frozen 1283 1283 Visual 2-17-2-5 2 365 Frozen . 1292 1292 Visual 2-17-2-6 2 366 1382 1504 1382 Scale 2-17-2-7 2 367 1440 1468 1440 Scale 2-17-2-8 2 368 1395 1444 1395 Scale 2-17-2-9 2 369 Frozen 1277 1277 Visual 2-18-2-1 2 370 1542 1542 Scale 2-18-2-2 2 371 1530 1530 Scale 2-18-2-3 2 372 Frozen _ 1304 1304 Visual 2-18-2-4 2 373 Frozen . 1467 1467 Visual 2-18-2-5 2 374 Frozen 1134 1134 Visual 2-18-2-6 2 375 Frozen 1345 1345 Visual 2-18-2-7 2 376 Frozen 1507 1507 ICEMANTm 2-18-2-8 2 377 Frozen 1239 1239 Visual 2-18-2-9 2 378 Frozen 1143 1143 Visual 2-19-2-1 2 379 Frozen 1199 1199 Visual 2-19-2-2 2 380 1570 1615 1570 Scale 2-19-2-3 2 381 Frozen  : 1478 1478 Visual 2-19-2-4 2 382 Frozen 1456 1456 Visual 2-19-2-5 2 383 Frozen 1395 1395 Visual 2-19-2-6 2 384 Frozen _ 1362 1362 Visual 2-19-2-7 2 385 1585 1287 1585 Scale 2-19-2-8 2 386 Frozen 1412 1412 Visual 2-19-2-9 2 387 Frozen 1254 1254 Visual 2-20-2-1 2 388 1428 1567 1428 Scale 2-20-2-2 2 389 1406 1539 1406 Scale 2-20-2-3 2 390 1440 1458 1440 Scale 2-20-2-4 2 391 1383 1414 1383 Scale 2-20-2-5 2 392 1194 1274 1194 Scale 2-20-2-6 2 393 1436 1342 1436 Scale 2-20-2-7 2 394 1478 1544 1478 Scale 2-20-2-8 2 395 1493 1495 1493 Scale 2-20-2-9 2 396 1574 1574 1574 Scale 2-21-2-1 2 397 1252 1258 1252 Scale 2-21-2-2 2 398 1206 1219 1206 Scale 2-21-2-3 2 399 1133 1161 1133 Scale 2-21-2-4 2 400 1212 1210 1212 Scale 2-21-2-5 2 401 1127 1138 1127 Scale 2-21-2-6 2 402 1158 1191 llS8 Scale 2-21-2-7 2 403 1287 1385 :1287 Scale 2-21-2-8 2 404 1432 1434 1432 Scale 2-21-2-9 2 405 Frozen . 1235 1235 Visul 2-22-2-1 2 406 Frozen 1478 1478 Visual 2-22-2-2 2 407 1500 1494 1S00 Scale 2-22-2-3 2 408 Frozen - 1476 1476 Visual 2-22-2-4 2 409 Frozen _ 1401 1401 Visual 2-22-2-5 2 410 Frozen 1341 1341 Visual 2-22-2-6 2 411 Frozen _ 1222 1222,Visual 2-22-2-7 2 412 1538 1529 IS38 Scale 2-22-2-8 2 413 1485 1 1485 Scale TOPICAL REPORT ICUG-001, Revision 2 A-12 May 2003 DRAFr

2-22-2-9 2 414 1472 1472 Scale 2-23-2-1 2 415 1521 1521 Scale 2-23-2-2 2 416 1564 _ 1564 Scale 2-23-2-3 2 417 1550 1593 1550 Scale 2-23-2-4 2 418 1489 1497 1489 Scale 2-23-2-5 2 419 1360 1366 1360 Scale 2-23-2-6 2 420 1454 1448 1454 Scale 2-23-2-7 2 421 Frozen 1584 1584 ICEMANTm 2-23-2-8 2 422 1537 1544 1537 Scale 2-23-2-9 2 423 Frozen 1145 1145 Visual 2-24-2-1 2 424 946 980 946 Scale 2-24-2-2 2 425 1198 1171 1198 Scale 2-24-2-3 2 426 1248 1329 1248 Scale 2-24-2-4 2 427 1254 1266 1254 Scale 2-24-2-5 2 428 1384  : 1384 Scale 2-24-2-6 2 429 Frozen 1134 1134 Visual 2-24-2-7 2 430 Frozen 1151 1151 Visual 2-24-2-8 2 431 Frozen 1074 1074 Visual 2-24-2-9 2 432 Frozen 921 921 Visual 2-01-3-1 3 433 1424 1282 1424 Scale 2-01-3-2 3 434 1518 1512 1518 Scale 2-01-3-3 3 435 1468 1476 1468 Scale 2-01-3-4 3 436 1374 1357 1374 Scale 2-01-3-5 3 437 1227 1285 1227 Scale 2-01-3-6 3 438 1163 1312 1163 Scale 2-01-3-7 3 439 1216 1221 1216 Scale 2-01-3-8 3 440 1122 1216 1122 Scale 2-01-3-9 3 441 909 923 909 Scale 2-02-3-1 3 442 Frozen 934 934 Visual 2-02-3-2 3 443 1200 1195 1200 Scale 2-02-3-3 3 444 1216 1208 1216 Scale 2-02-3-4 3 445 1398 1406 1398 Scale 2-02-3-5 3 446 1165 1238 1165 Scale 2-02-3-6 3 447 1182 1203 1182 Scale 2-02-3-7 3 448 1192 1212 1192 Scale 2-02-3-8 3 449 1240 1225 1240 Scale 2-02-3-9 3 450 1329 1339 1329 Scale 2-03-3-1 3 451 Frozen 1146 1146 Visual 2-03-3-2 3 452 1435 1426 1435 Scale 2-03-3-3 3 453 1434 1424 1434 Scale 2-03-3-4 3 454 1395 1351 1395 Scale 2-03-3-5 3 455 1508 1438 1508 Scale 2-03-3-6 3 456 1506 1523 1506 Scale 2-03-3-7 3 457 1491 1432 1491 Scale 2-03-3-8 3 458 1462 1424 1462 Scale 2-03-3-9 3 459 Frozen 1378 1378 Visual 2-04-3-1 3 460 1439 1487 1439 Scale 2-04-3-2 3 461 1502 1478 1502 Scale 2-04-3-3 3 462 1530 1461 1530 Scale 2-04-3-4 3 463 1426 1445 1426 Scale 2-04-3-5 3 464 1415 1475 1415 Scale 2-04-3-6 3 465 1444 14851 1444 Scale TOPICAL REPORT ICUG-001, Revision 2 A-13 May 2003 DRAFT

2-04-3-7 3 466 1468 1501 1468 Scale 2-04-3-8 3 467 1458 1486 1458 Scale 2-04-3-9 3 468 1362 1419 1362 Scale 2-05-3-1 3 469 Frozen 1389 1389 ICEMANm 2-05-3-2 3 470 1440 1466 1440 Scale 2-05-3-3 3 471 1356 1391 1356 Scale 2-05-3-4 3 472 1380 1467 1380 Scale 2-05-3-5 3 473 Frozen 1411 1411 isal 2-05-3-6 3 474 1398 1433 1398 Scale 2-05-3-7 3 475 1322 1421 1322 Scale 2-05-3-8 3 476 1439 1452 1439 Scale 2-05-3-9 3 477 1392 1360 1392 Scale 2406-3-1 3 478 Frozen 1516 1516 ICEMIAN' 2-06-3-2 3 479 1419 1551 1419 Scale 2406-3-3 3 480 1580 1589 1580 Scale 2-06-3-4 3 481 Frozen 1500 1500 Visual 2406-3-5 3 482 Frozen 1508 1508 ICEMANrm 24063-6 3 483 1454 1505 1454 Scale 2406-3-7 3 484 1374 1565 1374 Scale 2-06-3-8 3 485 1530 1579 1530 Scale 2-06-3-9 3 486 Frozen 1453 1453 Visual 2-07-3-1 3 487 1450 1450 Scale 2-07-3-2 3 488 1502 1510 1502 Scale 2-07-3-3 3 489 1487 1503 1487 Scale 2-07-3-4 3 490 1474 1472 1474 Scale 2-07-3-5 3 491 1485 1422 1485 Scale 2-07-3-6 3 492 1478 1477 1478 Scale 2-07-3-7 3 493 1493 1499 1493 Scale 2-07-3-8 3 494 1500 1527 1500 Scale 2-07-3-9 3 495 1480 1523 1480 Scale 2-08-3-1 3 496 1350 1405 1350 Scale 2-08-3-2 3 497 1256 1296 1256 Scale 2-08-3-3 3 498 1270 1317 1270 Scale 2-08-3-4 3 499 1078 1120 1078 Scale 2-08-3-5 3 500 1126 1182 1126 Scale 2-08-3-6 3 501 1392 1392 Scale 2-08-3-7 3 502 1257 1252 1257 Scale 2-08-3-8 3 503 1310 1332 13 10 Scale 2-08-3-9 3 504 1440 1200 1440 Scale 2-09-3-1 3 505 1480 1589 1480 Scale 2-09-3-2 3 506 1507 1487 1507 Scale 2-09-3-3 3 507 1540 1573 1540 Scale 2-09-3-4 3 508 1507 1620 1507 Scale 2-09-3-5 3 509 1435  : 1435 Scale 2-09-3-6 3 510 1454 1370 1454 Scale 2-09-3-7 3 511 1408 1434 1408 Scale 2-09-3-8 3 512 1404 1418 1404 Scale 2-09-3-9 3 513 Frozen 1240 1240 Visual 2-10-3-1 3 514 1560 1553 1560 Scale 2-10-3-2 3 515 1498 1502 1498 Scale 2-10-3-3 3 516 1474 1479 1474 Scale 2-10-34 3 517 1407 1404 1407 Scale TOPICAL REPORT ICUG-001, Revision 2 A-14 May 2003 DRAFT

2-10-3-5 3 518 1369 1342 1369 Scale 2-10-3-6 3 5 19 1438 1457 1438 Scale 2-10-3-7 3 520 1468 1422 1468 Scale 2-10-3-8 3 521 1542 1514 1542 Scale 2-10-3-9 3 522 Frozen 1490 1490 Visual 2-11-3-1 3 _ 523 1252 1514 1252 Scale 2-11-3-2 3 524 1494 1506 1494 Scale 2-11-3-3 3 525 1512 1511 1512 Scale 2-11-3-4 3 526 1531 1555 1531 Scale 2-11-3-5 3 527 Frozen 1283 1283 Visual 2-11-3-6 3 528 1523 1517 1523 Scale 2-11-3-7 3 529 1545 1557 1545 Scale 2-11-3-8 3 530 1544 1554 1544 Scale 2-11-3-9 3 531 1551 1572 1551 Scale 2-12-3-1 3 _ 532 1470 1417 1470 Scale 2-12-3-2 3 533 1446 1470 1446 Scale 2-12-3-3 3 534 1425 1475 1425 Scale 2-12-3-4 3 535 1406 1402 1406 Scale 2-12-3-5 3 536 1390 1390 Scale 2-12-3-6 3 537 1384 1407 1384 Scale 2-12-3-7 3 538 1410 1428 1410 Scale 2-12-3-8 3 539 1454 1471 1454 Scale 2-12-3-9 3 540 1450 1385 1450 Scale 2-13-3-1 3 541 1297 1267 1297 Scale 2-13-3-2 3 542 1334 1374 1334 Scale 2-13-3-3 3 543 1362 1389 1362 Scale 2-13-3-4 3 544 1320 1378 1320 Scale 2-13-3-5 3 545 1338 1386 1338 Scale 2-13-3-6 3 546 1329 1368 1329 Scale 2-13-3-7 3 547 1318 1354 1318 Scale 2-13-3-8 3 548 1384 1451 1384 Scale 2-13-3-9 3 549 Frozen 1402 1402 Visual 2-14-3-1 3 550 1220 1375 1220 Scale 2-14-3-2 3 551 1302 1339 1302 Scale 2-14-3-3 3 552 1238 1330 1238 Scale 2-14-3-4 3 553 1238 1256 1238 Scale 2-14-3-5 3 554 Frozen 1440 1440 Visual 2-14-3-6 3 555 1176 1216 1176 Scale 2-14-3-7 3 556 1220 1271 1220 Scale 2-14-3-8 3 557 1277 1318 1277 Scale 2-14-3-9 3 558 Frozen 1207 1207 ICEMAN' 2-15-3-1 3 559 1406 1425 1406 Scale 2-15-3-2 3 560 1367 1383 1367 Scale 2-15-3-3 3 561 1315 1344 1315 Scale 2-15-34 3 562 1243 1278 1243 Scale 2-15-3-5 3 563 1228 1270 1228 Scale 2-15-3-6 3 564 1278 1300 1278 Scale 2-15-3-7 3 565 1287 1319 1287 Scale 2-15-3-8 3 566 1304 1338 1304 Scale 2-15-3-9 3 567 1345 1378 1345 Scale 2-16-3-1 3 568 1544 13751 1544 Scale 2-16-3-2 3 569 1370 14521 1370 Scale TOPICAL REPORT ICUG-001, Revision 2 A-15 May 2003 DRAFT

2-16-3-3 3 570 1400 1449 1400 Scale 2-16-34 3 571 1374 1442 1374 Scale 2-16-3-5 3 572 1392 1468 1392 Scale 2-16-3-6 3 573 1354 1400 1354 Scale 2-16-3-7 3 574 1402 1431 1402 Scale 2-16-3-8 3 575 1326 1369 1326 Scale 2-16-3-9 3 576 1391 1427 1391 Scale 2-17-3-1 3 577 1622 1406 1622 Scale 2-17-3-2 3 578 1548 1409 1548 Scale 2-17-3-3 3 579 1366 1389 1366 Scale 2-17-3-4 3 580 1337 1383 1337 Scale 2-17-3-5 3 581 1345 1384 1345 Scale 2-17-3-6 3 582 1387 1407 1387 Scale 2-17-3-7 3 583 1377 1405 1377 Scale 2-17-3-8 3 584 1372 1400 1372 Scale 2-17-3-9 3 585 1421 1523 1421 Scale 2-18-3-1 3 586 1480 1480 Scale 2-18-3-2 3 587 1425 1425 Scale 2-18-3-3 3 588 1411 1472 _ X X 1411 Scale 2-18-34 3 589 1310 1375 1310 Scale 2-18-3-5 3 590 1396 1413 1396 Scale 2-18-3-6 3 591 1382 1422 1382 Scale 2-18-3-7 3 592 1449 1390 1449 Scale 2-18-3-8 3 593 1524 1497 1524 Scale 2-18-3-9 3 594 1552 1552 Scale 2-19-3-1 3 595 Frozen 1337 1337 Visual 2-19-3-2 3 596 1496 1528 1496 Scale 2-19-3-3 3 597 1484 1523 1484 Scale 2-19-34 3 598 1498 1518 1498 Scale 2-19-3-5 3 599 Frozen _ 1487 1487 Visual 2-19-3-6 3 600 1478 1504 1478 Scale 2-19-3-7 3 601 1474 1490 1474 Scale 2-19-3-8 3 602 1510 1558 1510 Scale 2-19-3-9 3 603 1436 1522 1436 Scale 2-20-3-1 3 604 1438 1477 1438 Scale 2-20-3-2 3 605 1421 1457 1421 Scale 2-20-3-3 3 606 1365 1408 1365 Scale 2-20-34 3 607 1271 1306 1271 Scale 2-20-3-5 3 608 1288 1313 1288 Scale 2-20-3-6 3 609 1345 1371X  : 1345 Scale 2-20-3-7 3 610 1399 1416 1399 Scale 2-20-3-8 3 611 1446 1452 1446 Scale 2-20-3-9 3 612 1291 1490 1291 Scale 2-21-3-1 3 613 1252 1259 1252 Scale 2-21-3-2 3 614 1205 1230 1205 Scale 2-21-3-3 3 615 1390 1392 1390 Scale 2-21-3-4 3 616 1341 1376 1341 Scale 2-21-3-5 3 617 1179 1212 1179 Scale 2-21-3-6 3 618 1167 1203 1167 Scale 2-21-3-7 3 619 1262 1290 1262 Scale 2-21-3-8 3 620 1367 1372 1367 Scale 2-21-3-9 3 621 Frozen - 1254 1254 Visual TOPICAL REPORT ICUG-001, Revision 2 A-16 May 2003 DRAFT

2-22-3-1 3 622 1440 1440 Scale 2-22-3-2 3 623 1494 1584 1494 Scale 2-22-3-3 3 624 1465 1508 1465 Scale 2-22-3-4 3 625 1503 1426 1503 Scale 2-22-3-5 3 626 1464 1464 Scale 2-22-3-6 3 627 1420 1444 1420 Scale 2-22-3-7 3 628 1413 1435 . 1413 Scale 2-22-3-8 3 629 1370 1394 1370 Scale 2-22-3-9 3 630 1396 1482 1396 Scale 2-23-3-1 3 631 1414 1414 Scale 2-23-3-2 3 632 1445 1451 l 1445 Scale 2-23-3-3 3 633 1437 1437 1437 Scale 2-23-3-4 3 634 1406 1426 1406 Scale 2-23-3-5 3 635 1356 1367 1356 Scale 2-23-3-6 3 636 1392 1399 1392 Scale 2-23-3-7 3 637 1442 1451 1442 Scale 2-23-3-8 3 638 1458 1471 1458 Scale 2-23-3-9 3 639 1424 1401 1424 Scale 2-24-3-1 3 640 1136 1131 1136 Scale 2-24-3-2 3 641 1229 1262 . 1229 Scale 2-24-3-3 3 642 1156 1142 1156 Scale 2-24-3-4 3 643 1274 1302 1274 Scale 2-24-3-5 3 644 1281 1306 1281 Scale 2-24-3-6 3 645 1250 1255 . 1250 Scale 2-24-3-7 3 646 1348 1414 1348 Scale 2-24-3-8 3 647 1495 1485 1495 Scale 2-24-3-9 3 648 1442 1442 Scale 2-01-4-1 4 649 1318 1312 1318 Scale 2-014-2 4 650 1320 1267 1320 Scale 2-01-4-3 4 651 1306 1265 1306 Scale 2-0144 4 652 1306 1312 1306 Scale 2-014-5 4 653 1223 1263 1223 Scale 2-01-4-6 4 654 1277 1311 1277 Scale 2-01-4-7 4 655 1209 1231 1209 Scale 2-01-4-8 4 656 1078 1205 1078 Scale 2-014-9 4 657 1054 1105 1054 Scale 2-02-4-1 4 658 1165 1279 1165 Scale 2-024-2 4 659 1185 1163 1185 Scale 2-02-4-3 4 660 1197 1212 1197 Scale 2-02-44 4 661 1328 1339 1328 Scale 2-024-5 4 662 1339 1339 Scale 2-024-6 4 663 1310 1328 1310 Scale 2-024-7 4 664 1396 1415 1396 Scale 2-02-4-8 4 665 - _ 1140 1182 1140 Scale 2-02-4-9 4 666 1322 1322 1322 Scale 2-034-1 4 667 1242 _ 1242 Scale 2-03-4-2 4 668 1218 1254 1218 Scale 2-034-3 4 669 1274 1279 1274 Scale 2-03-4-4 4 670 1215 1248 1215 Scale 2-034-5 4 671 1328 1286 1328 Scale 2-03-4-6 4 672 1268 1262 1268 Scale 2-034-7 4 673 1350 1298 1350 Scale TOPICAL REPORT ICUG-001, Revision 2 A-17 May 2003 DRAFT

2-03-4-8 4 674 1465 1465 Scale 2-03-4-9 4 675 1219 .1134 1219 Scale 2-0441 4 676 1294 1302 1294 Scale 2-0442 4 677 1284 1302 1284 Scale 2-0443 4 678 1288 1325 . 1288 Scale 2-0444 4 679 1276 1296 _ 1276 Scale 2-04-4-5 4 680 1302 1300 1302 Scale 2-04-4-6 4 681 1268 1286 1268 Scale 2-044-7 4 682 1268 1267 1268 Scale 2-04-8 4 683 1255 1274 1255 Scale 2-044-9 4 684 1209 1191 1209 Scale 2-0541 4 685 1313 1252 1313 Scale 2-054-2 4 686 1308 1324 1308 Scale 2-054-3 4 687 1266 1293 1266 Scale 205-4-4 4 688 1264 1253 1264 Scale 2-054-5 4 689 1340 1340 Scale 245-4-6 4 690 1293 1251 1293 Scale 2-054-7 4 691 1320 1268 1320 Scale 2-0548 4 692 1332 1403 1332 Scale 2-05-4-9 4 693 1380 1429 1380 Scale 2-06-4-1 4 694 1377 1375 1377 Scale 2-06-4-2 4 695 1386 1399 1386 Scale 2-06-4-3 4 696 1416 1432 1416 Scale 2-0644 4 697 1405 1446 1405 Scale 2-06-4-5 4 698 1470 1388 1470 Scale 2-06-4-6 4 699 1405 1425 1405 Scale 2-06-4-7 4 700 1414 1441 1414 Scale 2-06-4-8 4 701 1428 1455 1428 Scale 2-06-4-9 4 702 1291 1380 . 1291 Scale 2-07-4-1 4 703 1280 1320 1280 Scale 2-074-2 4 704 1305 1329 1305 Scale 2-07-4-3 4 705 1389 1346 1389 Scale 2-07-4-4 4 706 1344 1331 1344 Scale 2-07-4-5 4 707 1342 1334  :: 1342 Scale 2-07-4-6 4 708 1322 1364 - 1322 Scale 2-0747 4 709 1347 1334 1347 Scale 2-07-48 4 710 1338 1355  : 1338 Scale 2-074-9 4 711 1362 1386 1362 Scale 2-08-4-1 4 712 1322 1351 1322 Scale 2-084-2 4 713 1206 1222 _ 1206 Scale 2-08-4-3 4 714 1207 1240 1207 Scale 2-0844 4 715 1128 1162 1128 Scale 2-08-4-5 4 716 1228 1240 . 1228 Scale 2-084-6 4 717 1348 1443 1348 Scale 2-084-7 4 718 1182 1212 1182 Scale 2-08-4-8 4 719 1223 1245 1223 Scale 2-084-9 4 720 1295 1279 1295 Scale 2-094-1 4 721 1462 1336 1462 Scale 2-094-2 4 722 1379 1379 1379 Scale 2-094-3 4 723 1354 1377 1354 Scale 2-094-4 4 724 1364 1380 1364 Scale 2-094-5 4 725 1255 1310 1255 Scale TOPICAL REPORT ICUG-001, Revision 2 A-18 May 2003 DRAFT

2-094-6 4 726 1351 1364 1351 Scale 2-09-4-7 4 727 1342 1328 1342 Scale 2-09-4-8 4 728 1349 1353 1349 Scale 2-09-4-9 4 729 1356 1397 1356 Scale 2-10-4-1 4 730 1400 1422 1400 Scale 2-104-2 4 731 1382 1267 1382 Scale 2-10-4-3 4 732 1347 1348 1347 Scale 2-10-44 4 733 1340 1347 1340 Scale 2-10-4-5 4 734 1344 1308 1344 Scale 2-104-6 4 735 1360 1377 1360 Scale 2-104-7 4 736 1385 1399 1385 Scale 2-10-4-8 4 737 1430 1434 1430 Scale 2-10-4-9 4 738 Frozen 1463 1463 Visual 2-11-4-1 4 739 1387 1402 1387 Scale 2-114-2 4 740 1374 1394 1374 Scale 2-11-4-3 4 741 1424 1445 1424 Scale 2-11-4-4 4 742 1444 1473 1444 Scale 2-11-4-5 4 743 1478 1491 1478 Scale 2-11-4-6 4 744 1434 1429 1434 Scale 2-11-4-7 4 745 1422 1425 1422 Scale 2-11-4-8 4 746 1397 1416 1397 Scale 2-11-4-9 4 747 1432 1463 1432 Scale 2-124-1 4 748 1328 1331 1328 Scale 2-12-4-2 4 749 1332 1386 1332 Scale 2-124-3 4 750 1322 1327 1322 Scale 2-1244 4 751 1343 1402 1343 Scale 2-124-5 4 752 1278 1296 1278 Scale 2-124-6 4 753 1264 1427 1264 Scale 2-12-4-7 4 754 1282 1294 1282 Scale 2-12-44 4 755 1322 1328 1322 Scale 2-12-4-9 4 756 1298 1317 1298 Scale 2-134-1 4 757 1314 1321 1314 Scale 2-134-2 4 758 1219 1228 1219 Scale 2-134-3 4 759 1245 1264 1245 Scale 2-13-44 4 760 1247 1277 1247 Scale 2-13-4-5 4 761 1251 1239 1251 Scale 2-13-4-6 4 762 1208 1183 1208 Scale 2-134-7 4 763 1314 1338 1314 Scale 2-1348 4 764 1267 1325 1267 Scale 2-134-9 4 765 1349 1419 1349 Scale 2-144-1 4 766 1242 1276 1242 Scale 2-14-4-2 4 767 1205 1253 1205 Scale 2-144-3 4 768 1324 1347 1324 Scale 2-144-4 4 769 1170 1195 1170 Scale 2-144-5 4 770 1132 1161 1132 Scale 2-144-6 4 771 1187 1214 1187 Scale 2-14-4-7 4 772 1204 1230 1204 Scale 2-144-8 4 773 .1209 1204 1209 Scale 2-144-9 4 774 Frozen 1456 1456 Visual 2-154-1 4 775 1228 1247, 1228 Scale 2-154-2 4 776 1199 1225 119S Scale 2-154-3 4 777 1218 1248 1 1218 Scale TOPICAL REPORT ICUG-001, Revision 2 A-19 May 2003 DRAFT

2-15-4-4 4 778 1202 1246 1202 Scale 2-15-4-5 4 779 1230 1317 1230 Scale 2-15-4-6 4 780 1233 1262 1233 Scale 2-15-4-7 4 781 1238 1270 1238 Scale 2-15-4-8 4 782 1218 1245 1218 Scale 2-15-4-9 4 783 1262 1298 1262 Scale 2-16-4-1 4 784 1239 1297 1239 Scale 2-16-4-2 4 785 1228 1285 1228 Scale 2-16-4-3 4 786 1254 1302 1254 Scale 2-16-4-4 4 787 1226 1296 1226 Scale 2-16-4-5 4 788 1247 1306 1247 Scale 2-16-4-6 4 789 1176 1176 Scale 2-16-4-7 4 790 1181 1213 1181 Scale 2-16-4-8 4 791 1167 1229 1167 Scale 2-16-4-9 4 792 1156 1215 1156 Scale 2-17-4-1 4 793 1338 1342 1338 Scale 2-17-4-2 4 794 1298 1368 1298 Scale 2-17-4-3 4 795 1294 1315 1294 Scale 2-17-4-4 4 796 1234 1257 1234 Scale 2-17-4-5 4_ _ 797 1321 1298 1321 Scale 2-17-4-6 04 _ S 798 1231 1283 1231 Scale 2-17-4-7 4_ _ 799 1254 1286 1254 Scale 2-17-4-8 4 800 1275 1285 1275 Scale 2-17-4-9 4 801 1240 1272 1240 Scale 2-18-4-1 4 .802 1274 1341 1274 Scale 2-18-4-2 04 T j 803 7 .1294 1349 1294 Scale 2-18-4-3 4 804 1250 1318 1250 Scale 2-18-4-4 4 80S 1211 1388 1211 Scale 2-18-4-5 04 X _ 806 1245 1245 Scale 2-18-4-6 74 q807 7  : 1285 1342 1285 Scale 2-18-4-7 4 808 1293 1344 1293 Scale 2-18-" 4 809 1290 1332 1290 Scale 2-18-4-9 4 810 1241 1275 1241 Scale 2-19 41 4 811

_ - _1411 1439 1411 Scale 2-19-4-2 4 812 1361 1410 1361 Scale 2-19-4-3 4 813 1385 1434 1385 Scale 2-194.4 4 814

_ =1387 1422 1387 Scale 2-19-4-5 4 815 Froeno 1320 1320 Visual 2-19-4-6 4 816 1385 1411 1385 Scale 2-19 47 4 817 1341 1371 1341 Scale 2-19-4-8 4 818 1327 1378 1327 Scale 2-19-49 4 819 1320 1358 1320 Scale 2-20-4-1 4 820

_ _ 1239 1332 1239 Scale 2-20-4-2 4 821

_ 1286 1328 1286 Scale 2-20-4-3 4 822 1259 1294 1259 Scale 2-204-4 4 823 1243 -1285 1243 Scale 2-20-4-5 4 824 1231 1301 1231 Scale 2-20-4-6 4 825 1212 1293 1212 Scale 2-20-4-7 4 826 1301 1314 1301 Scale 2-20-4-8 4 827 1317 1382 1317 Scale 2-20-4-9 4 88 1408 1438 1408 Scale 2-21-4-1 4 829 1191 1216 1191 Scale TOPICAL REPORT ICUG-001, Revision 2 A-20 May 2003 DRAFI'

2-214-2 4 830 1143 1164  : 1143 Scale 2-214-3 4 831 1161 1190 1161 Scale 2-214-4 4 832 1357 1213 1357 Scale 2-214-5 4 833 1163 1163 Scale 2-214-6 4 834 1166 1209 1166 Scale 2-21-4-7 4 835 1180 1219 1180 Scale 2-21-48 4 836 1242 1265 1242 Scale 2-214-9 4 837 1297 1336 1297 Scale 2-224-1 4 838 1348 1368 1348 Scale 2-224-2 4 839 1322 1364 1322 Scale 2-224-3 4 840 1341 1362 1341 Scale 2-22-4-4 4 841 1348 1352 _ 1348 Scale 2-22-4-S 4 842 1345 1345 Scale 2-22-4-6 4 843 1316 1339 1316 Scale 2-22-4-7 4 844 1273 1365 1273 Scale 2-22-4-8 4 845 1229 1267 1229 Scale 2-224-9 4 846 1226 1263 1226 Scale 2-234-1 4 847 1294 1304 1294 Scale 2-234-2 848 1292 1309 1292 Scale 2-23-4-3 4 849 1325 1321 1325 Scale 2-23-4-4 4 850 1322 1340 1322 Scale 2-23-4-5 4 851 1282 1284 1282 Scale 2-23-4-6 4 852 1240 1236 1240 Scale 2-234-7 4 _ 853 1280 1277 1280 Scale 2-23-4-8 4 854 1315 1302 1315 Scale 2-23-4-9 4 855 1288 1322 1288 Scale 2-24-4-1 4 856 1211 1090 1211 Scale 2-24-4-2 4 857 1188 1080 1188 Scale 2-24-4-3 4 858 1195 1243 1195 Scale 2-24-4-4 4 859 1234 1267 1234 Scale 2-24-4-5 4 860 1393 1296 1393 Scale 2-24-4-6 4 861 1250 1251 1250 Scale 2-24-4-7 4 862 1277 1290 1277 Scale 2-24-4-8 4 863 1288 1328 1288 Scale 2-24-4-9 4 864 1280 1307 1280 Scale 2-01-5-1 5 865 1198 1182 1199 Scale 2-01-5-2 5 866 1273 1255 1273 Scale 2-01-5-3 5 867 1248 1240 1248 Scale 2-01-5-4 5 868 1254 1248 1254 Scale 2-01-5-5 5 869 1221 1249 1221 Scale 2-01-5-6 5 870 1203 1250 1203 Scale 2-01-5-7 5 871 1173 1236 1173 Scale 2-01-5-8 5 872 1182 1185 1182 Scale 2-01-5-9 5 873 989 1094 989 Scale 2-02-5-1 5 874 1163 1163 Scale 2-02-5-2 5 875 1136 1135 _ _ _1136 Scale 2-02-5-3 5 876 1160 1164 1160 Scale 2-02-5-4 5 877 920 1115 920 Scale 2-02-5-5 5 878 1095 1126 1095 Scale 2-02-5-6 5 879 1063 1073. 1063 Scale 2-02-5-7 5 880 1071 1159 1071_Scale 2-02-5-8 5 881 1075 1140 1075 Scale TOPICAL REPORT ICUG-001, Revision 2 A-21 May 2003 DRAFT

2-02-5-9 5 882 1110 1168 1 10 Scale 2-03-5-1 5 883 1366 1366 Scale 2-03-5-2 5 884 1225 1215 1225 Scale 2-03-5-3 5 885 1151 1137 1151 Scale 2-03-5-4 5 886 1340 1339 1340 Scale 2-03-5-5 5 887 1314 1230 1314 Scale 2-03-5-6 5 888 1260 1210 1260 Scale 2-03-5-7 5 889 1265 1196 1265 Scale 2-03-5-8 5 890 1250 1209 1250 Scale 2-03-5-9 5 891 1260 1168 1260 Scale 2-04-5-1 5 892 1401 1285 1401 Scale 2-04-5-2 5 893 1354 1390 1354 Scale 2-04-5-3 5 894 1327 1335 1327 Scale 2-04-5-4 5 895 1296 1315 1296 Scale 2-04-5-5 5 896 1248 1268 1248 Scale 2-04-5-6 5 897 1326 1348 1326 Scale 2-04-5-7 5 898 1190 1241 1190 Scale 2-04-5-8 5 899 1245 1283 1245 Scale 2-04-5-9 5 900 1178 1174 1178 Scale 2-05-5-1 5 901 1271 1270 1271 Scale 2-05-5-2 5 902 1300 1313 1300 Scale 2-05-5-3 5 903 1246 1288 1246 Scale 2-05-5-4 5 904 1293 1312 1293 Scale 2-05-5-5 5 905 1201 1236 1201 Scale 2-05-5-6 5 906 1213 1222 _ 1213 Scale 2-05-5-7 5 907 1314 1303 1314 Scale 2-05-5-8 5 908 1217 1256 1217 Scale 2-05-5-9 5 909 1236 1248 1236 Scale 2-06-5-1 5 910 1292 1200 1292 Scale 2-06-5-2 5 911 1358 1389 1358 Scale 2406-5-3 5 912 1417 1452 _ 1417 Scale 2-06-5-4 5 913 1276 1290 1276 Scale 2-06-5-5 5 914 1295 1310 _ 1295 Scale 2406-5-6 5 915 1294 1333 1294 Scale 2-06-5-7 5 916 1262 1298 1262 Scale 2406-5-8 5 917 1233 1237 _ 1233 Scale 2406-5-9 5 918 1196 1222 1196 Scale 2-07-5-1 5 919 1260 1263 1260 Scale 2-07-5-2 5_ 920 1189 1164 1189 Scale 2-07-5-3 5 921 1300 1288 1300 Scale 2-07-5-4 5 922 1354 1331 1354 Scale 2-07-5-5 5 923 1191 1201 1191 Scale 2-07-5-6 5 924 1387 1399 . 1387 Scale 2-07-5-7 5 925 1345 1330 1345 Scale 2-07-5-8 5 926 1333 1324 1333 Scale 2-07-5-9 5 927 1198 1220 1198 Scale 2-08-5-1 5 928 1229 1216 1229 Scale 2-08-5-2 5 929 1296 1332 1296 Scale 2-08-5-3 5 930 1290 1308 1290 Scale 2-08-5-4 5 931 1190 1207 1190 Scale 2-08-5-5 5 932 1152 1184_ 1152 Scale 2-08-5-6 5 933 1258 1269 1 1258 Scale TOPICAL REPORT ICUG-001, Revision 2 A-22 May 2003 DRAFT

2-08-5-7 5 934 1170 1176 1170 Scale 2-08-5-8 5 935 1195 1202 1195 Scale 2-08-5-9 5 936 1326 1278 1326 Scale 2-09-5-1 5 937 1343 1631 1343 Scale 2-09-5-2 5 938 1242 1266 1242 Scale 2-09-5-3 5 939 1185 1222 1185 Scale 2-09-5-4 5 940 1233 1254 1233 Scale 2-09-5-5 5 941 1245 1224 1245 Scale 2-09-5-6 5 942 1215 1242 1215 Scale 2-09-5-7 5 943 1165 1245 1165 Scale 2-09-5-8 5 944 1167 1214 1167 Scale 2-09-5-9 5 945 1179 1216 1179 Scale 2-10-5-1 5 946 1278 1292 1278 Scale 2-10-5-2 5 947 1282 1295 1282 Scale 2-10-5-3 5 948 1370 1438 1370 Scale 2-10-5-4 5 949 1250 1265 1250 Scale 2-10-5-5 5 950 1269 1222 1269 Scale 2-10-5-6 5 951 1276 1278 1276 Scale 2-10-5-7 5 952 1305 1447 1305 Scale 2-10-5-8 5 953 1339 1345 1339 Scale 2-10-5-9 5 954 Frozen 1300 1300 Visual 2-11-5-1 5 955 Frozen 1237 1237 Visual 2-11-5-2 5 956 1244 1260 1244 Scale 2-11-5-3 5 957 1291 1304 1291 Scale 2-11-5-4 5 958 1351 1362 1351 Scale 2-11-5-5 5 959 1337 1382 1337 Scale 2-11-5-6 5 960 1340 1346 1340 Scale 2-11-5-7 5 961 1284 1302 1284 Scale 2-11-5-8 5 962 1274 1297 1274 Scale 2-11-5-9 5 963 1240 1270 1240 Scale 2-12-5-1 5 964 1300 1305 1300 Scale 2-12-5-2 5 965 1245 1244 1245 Scale 2-12-5-3 5 966 1206 1219 1206 Scale 2-12-5-4 5 967 1190 1204 1190 Scale 2-12-5-5 5 968 1140 1183 1140 Scale 2-12-5-6 5 969 1348 1427 1348 Scale 2-12-5-7 5 970 1276 1249 1276 Scale 2-12-5-8 5 971 1220 1323 1220 Scale 2-12-5-9 5 972 1177 _ 1l198 1177 Scale 2-13-5-1 5 973

_ Frozen 1467 1467 Visual 2-13-5-2 5 974 1264 1306 1264 Scale 2-13-5-3 5 975 1329 1350 1329 Scale 2-13-54 5 976 1328 1363 1328 Scale 2-13-5-5 5 977 1256 1256 Scale 2-13-5-6 5 978 _ 1326 1345 1326 Scale 2-13-5-7 5 979 1268 1305 1268 Scale 2-13-5 8 5 980 1324 1343 1324 Scale 2-13-5-9 5 981 1336 1371 1336 Scale 2-14-5-1 5 982 1120 1166 1120 Scale 2-14-5-2 5 983 _ _ 1188 _ 1238 _ 1188 Scale 2-14-5-3 5 984 1180 1246 1180 Scale 2-14-5-4 5 985 1193 1258 11931 Scale TOPICAL REPORT ICUG-001, Revision 2 A-23 May 2003 DRAFT

2-14-5-5 5 986 1205 1318 1205 Scale 2-14-5-6 5 987 1246 1246 1246 Scale 2-14-5-7 5 988 1208 1204 1208 Scale 2-14-5-8 5 989 1205 1226 1205 Scale 2-14-5-9 5 990 Frozen 1233 1233 Visual 2-15-5-1 5 991 1346 1235 1346 Scale 2-15-5-2 5 992 1180 1187 1180 Scale 2-15-5-3 5 993 1273 1298 1273 Scale 2-15-5-4 5 994 1265 1291 1265 Scale 2-15-5-5 5 995 1320 1361 1320 Scale 2-15-5-6 5 996 1222 1241 1222 Scale 2-15-5-7 5 997 1178 1208 1178 Scale 2-15-5-8 5 998 1176 1200 1176 Scale 2-15-5-9 5 999 1289 _ 1289 Scale 2-16-5-1 5 1000 1211 1205 1211 Scale 2-16-5-2 5 1001 1315 1360 1315 Scale 2-16-5-3 5 1002 1280 1314 1280 Scale 2-16-5-4 5 1003 1316 1360 1316 Scale 2-16-5-5 5 1004 1111 1146 1111 Scale 2-16-5-6 5 1005 1155 1194 _ 1155 Scale 2-16-5-7 5 1006 1206 1206 Scale 2-16-5-8 5 1007 1318 1352 1318 Scale 2-16-5-9 5 1008 1210 1226 1210 Scale 2-17-5-1 5 1009 1209 1212 1209 Scale 2-17-5-2 5 1010 1224 1221 1224 Scale 2-17-5-3 5 1011 1373 1397 1373 Scale 2-17-5-4 5 1012 1246 1322 1246 Scale 2-17-5-5 5 1013 1347 1347 Scale 2-17-5-6 5 1014 1144 1178 1144 Scale 2-17-5-7 5 1015 1140 1164 1140 Scale 2-17-5-8 5 1016 1094 1183 1094 Scale 2-17-5-9 5 1017 1208 1228 1208 Scale 2-18-5-1 5 1_ 1018 1085 1191 1085 Scale 2-18-5-2 5 1019 1217 1252 1217 Scale 2-18-5-3 5 1020 1144 1208 1144 Scale 2-18-5-4 5 1021 1124 1152 1124 Scale 2-18-5-5 5 1022 1244 1306 1244 Scale 2-18-5-6 5 1023 1128 1190 1128 Scale 2-18-5-7 5 1024 1090 _ 1090 Scale 2-18-5-8 5 1025 1164 1247 1164 Scale 2-18-5-9 5 1026 1155 1193 1155 Scale 2-19-5-1 5 1027 1192 1229 1192 Scale 2-19-5-2 5 1028 1192 1259 1192 Scale 2-19-5-3 5 1029 1220 1257 1220 Scale 2-19-5-4 5 1030 1230 1261 1230 Scale 2-19-5-5 5 1031 1230 1267 1230 Scale 2-19-5-6 5 1032 1198 1265 1198 Scale 2-19-5-7 5 1033 1168 1223 1168 Scale 2-19-5-8 5 1034 1202 1238 1202 Scale 2-19-5-9 5 1035 1130 1191 1130 Scale 2-20-5-1 5 1036 1245 1309 1245 Scale 2-20-5-2 5 1037 1249 1311 1249 Scale TOPICAL REPORT ICUG-001, Revision 2 A-24 May 2003 DRAFT

2-20-5-3 5 1038 1196 1226 1196 Scale 2-20-5-4 5 1039 1218 1229 1218 Scale 2-20-5-5 5 1040 1331 1370 _ 1331 Scale 2-20-5-6 5 1041 1239 1267 1239 Scale 2-20-5-7 5 1042 1247 1257 1247 Scale 2-20-5-8 5 1043 1242 1278 1242 Scale 2-20-5-9 5 1044 1214 1477 1214 Scale 2-21-5-1 5 1045 1294 1336 _ 1294 Scale 2-21-5-2 5 1046 1130 1130 Scale 2-21-5-3 5 1047 1246 1203 1246 Scale 2-21-5-4 5 1048 1150 1164 1150 Scale 2-21-5-5 5 1049 1084 1084 Scale 2-21-5-6

_ 1050 1248 1301 1248 Scale 2-21-5-7 5 1051 1184 1214 1184 Scale 2-21-5-8 5 1052 1194 1205 _ 1194 Scale 2-21-59 1053 1154 1238 1154 Scale 2-22-5-1 1054 1275 1275 Scale 2-22-5-2 1055 1336 1357 1336 Scale 2-22-5-3 1056 1292 1288 1292 Scale 2-22-5-4 1057 1227 1250 1227 Scale 2-22-5-5 1058 1235 1266 1235 Scale 2-22-5-6 1059 1207 1235 1207 Scale 2-22--7 1060 1365 1371 1365 Scale 2-22-5-8 1061 1321 1334 1321 Scale 2-22-5-9 1062 1255 1272 1255 Scale 2-23-5-1 1063 1308 1323 1308 Scale 2-23-5-2 5 1064 1368 1408 1368 Scale 2-23-5-3 1065 1190 1215 l9C0 Scale 2-23-5-4 1066 1217 1220 1217 Scale 2-23-55 5 1067 1190 1201 l 190 Scale 2-23-5-6 5 1068 1192 1193 1192 Scale 2-23-5-7

_ 1069 1349 1351 1349 Scale 2-23-5-8 5 1070 1307 1261 1307 Scale 2-23-5-9 5 1071 1256 1275 1256 Scale 2-24-5-1 5 1072 1130 1150 1130 Scale 2-24-5-2 5 1073 1238 1301 1238 Scale 2-24-5-3 5 1074 1205 1198 1205 Scale 2-24-5-4 5 1075 1260 1265 1260 Scale 2-24-5-5 5 1076 1294 1309 1294 Scale 2-24-5-6 5 1077 1252 1278 1252 Scale 2-24-5-7 5 . 1078 1330 1333 1330 Scale 2-24-5-8

_ 1079 1176 1192 1176 Scale 2-24-5-9 1080 1158 1349 1158 Scale 2-01-6-1 6 1081 1396 1411 1396 Scale 2-01-6-2 6 1082 1214 1199 1214 Scale 2-013 1083 1239 1273 _ 1239 Scale 2-01-64 6 1084 1268 1241 1268 Scale 2-01-65 6 1085 1213 1216 1213 Scale 2-01-66 6 1086 1338 1397 1338 Scale 2-01-67 6 1087 1093 1147 1093 Scale 2-01-6-8 6 1088 1172 12531 1172 Scale 2-01-69 6 1089 877 1009 877 Scale TOPICAL REPORT ICUG-001, Revision 2 A-25 May 2003 DRAFT

2-02-6-1 6 190 968 1011 _ 968 Scale 2-02_2

_6 1091 962 959 962 Scale 2-023 1092 1044 1006 1044 Scale 2-02_ 6 1093 1144 1238 1144 Scale 2-02-6-5 6 1094 882 s 998 882 Scale 2-02-6-6 6 1095 942 993 942 Scale 2-02-6-7 1096 1075 1119 1075 Scale 2-02-6-8 6 1097 1223 1264 1223 Scale 2-029 6 1098 1088 1108 _ 1088 Scale 2-03-6-1 6 1099 1177 1177 Scale 2-03-6-2 6 1100 1295 1211 1295 Scale 2-03-6-3 6 1101 1200 1207 1200 Scale 2-03-6-4 6__ 1102 1310 1307 1310 Scale 2-03__5 6 1103 1140 1109 1140 Scale 2-03-6-6 6 1104 1362 1316 1362 Scale 2-03-6-7 6 1105 1194 1125 1194 Scale 2-03-6-8 6 1106 1232 1162 1232 Scale 2-03-6-9 6 1107 1213 1085 1213 Scale 2-04-6-1 6 1108 - 1362 1362 Scale 2-04-6-2 6 1109 1214 1229 1214 Scale 204 3 6______1169 1214 1169 Scale 2-04-6-4 6_ _ __ 1211 1235 1211 Scale 2404-6-5 6 1112 1268 1345 1268 Scale 2-04-6-6 6 1113 1175 1217 1175 Scale 2-04 7 61114 1134 1158 1134 Scale 2_04__ _6 1115 1145 1162 1145 Scale 2404-6-9 6 1116 1275 1199 1275 Scale 2-05_ _l_6 1117 1248 1262 1248 Scale 2-05-6-2 il1174 1118 1239 1174 Scale 2405-6-3 6 1119 1184 1249 1184 Scale 2-05-6-4 6 1120 1171 1236 1171 Scale 2405-6-5 6 1121 1218 1422 1218 Scale 24S5-6-6 6 1122 1143 1186 1143 Scale 2405-6-7 6 1123 1394 1469 1394 Scale 2_-05_68 6 1124 1173 1244 1173 Scale 2-05-6-9 6 115 1168 1166 1168 Scale 246 6-1 6 . 1126 1272 1269 1272 Scale 24 6-2 _ 6 1127 1319 1335 1319 Scale 2406-6-3 6 1128 1264 1297 1264 Scale 2406 6-4 6 1129 Frozen 1358 1358 ICEMANTm 2_0 6-5 6 1130 1413 1435 _ 1413 Scale 24 _6i-6-6 1131 1204 1245 1204 Scale 2406-6-7 1132 1338 1366 1338 Scale 20_6-8 1133 . 1298 1318 1298 Scale 24 __6-9 6 1134 1258 1258 Scale 2-07_ _ _ _6 1135 1221 1221 1221 Scale 2-07-62 6 1136 1183 1155 1183 Scale 2-07-63 6 1137 1243 1201 1243 Scale 2-07-64 6 1138 1272 1536 1272 Scale 2-07-65 6 1139 1236 1233 1236 Scale 2-07-66 6 1140 1250 12341 1250 Scale 2-07-67 6 1141 1282 1 1282 Scale TOPICAL REPORT ICUG-001, Revision 2 A-26 May 2003 DRAFT

2-07-68 6 1142 1284 1305 1284 Scale 2-07-69 6 1143 1186 1194 1186 Scale 2-08-6-1 6 1144 1201 1201 Scale 2-08-6-2 6 1145 1158 1179 1158 Scale 2-08-63 6 1146 1159 1174 1159 Scale 2-08-64 6 1147 1228 1258 1228 Scale 2-08-6-5 6 1148 1248 1255 1248 Scale 2-08-6-6 6 1149 1188 1201 1188 Scale 2-08-6-7 6 1150 1292 1269 1292 Scale 2-08-6-8 6 1151 1114 1127 11 14 Scale 2-08-6-9 6 1152 Frozen 1108 1108 Visual 2-09-6-1 6 1153 1278 1278 Scale 2-09-6-2 6 1154 1350 1331 _ 1350 Scale 2-09-6-3 6 1155 1265 1268 1265 Scale 2-09-6-4 6 1156 1328 1330 1328 Scale 2-09-65 6 1157 1163 1163 Scale 2-09-6-6 6 1158 1223 1240 1223 Scale 2-09-6-7 6 1159 1190 1201 1190 Scale 2-09-6-8 6 1160 1274 1276 1274 Scale 2-09-6-9 6 1161 1266 1317 1266 Scale 2-10-6-1 6 1162 1208 1088 1208 Scale 2-10-6-2 6 1163 1198 1214 1198 Scale 2-10-63 6 1164 1189 1211 1189 Scale 2-10-64 6 1165 1178 1237 1178 Scale 2-10-65 6 1166 1185 1199 118 Scale 2-10-66 6 1167 1363 1358 1363 Scale 2-10-67 6 1168 1240 1241 1240 Scale 2-10-6-8 6 1169 1252 1254 1252 Scale 2-10-69 6 1170 Frozen 1182 1182 Visual 2-11-6-1 6 1171 Frozen 1345 1345 Visual 2-11-6-2 6 1172 1320 1339 1320 Scale 2-11-6-3 6 1173 1212 1224 1212 Scale 2-11-64 6 1174 1269 1277 1269 Scale 2-11-6-5 6 1175 1288 1295 128_ Scale 2-11-66 6 1176 1250 1276 1250 Scale 2-11 6-7 6 1177 1206 1220 1206 Scale 2-11-6-8 6 1178 1282 1317 1282 Scale 2-11-6-9 6 1179 1205 1205 1205 Scale 2-12-61 6 1180 Frozen 1336 1336 Visual 2-12-62 6 1181 1225 1254 1225 Scale 2-12-63 6 1182 1194 1208 1194 Scale 2-12-64 6 1183 1258 1309 1258 Scale 2-12-65 6 1184 Frozen 1103 1103 Visual 2-12-66 6 1185 1148 1195 1148 Scale 2-12-6-7 6 1186 1145 1157 1145 Scale 2-12-68 6 1187 1298 1439 1298 Scale 2-12-69 6 1188 1328 1379 1328 Scale 2-13-6-1 6 1189 Frozen 1401 1401 Visual 2-13-6-2 6 1190 1302 1312 1302 Scale 2-13-6-3 6 1191 1291 1340 1291 Scale 2-13-64 6 1192 1162 1236 116;1 Scale 2-13-6-5 6 1193 1177 1207 117, Scdle TOPICAL REPORT ICUG-001, Revision 2 A-27 May 2003 DRAFT

2-13-6-6 6 1194 1259 1293 1259 Scale 2-13-6-7 6 1195 1256 1253 1256 Scale 2-13-68 6 1196 1281 1317 1281 Scale 2-13-69 6 1197 1326 1353 1326 Scale 2-14-6-1 6 1198 1181 1163 1181 Scale 2-14-6-2 6 1199 1138 1236 1138 Scale 2-14-6-3 6 1200 _ 1138 1148 1138 Scale 2-14-64 6 1201 1178 1253 1178 Scale 2-14-6-5 6 1202 1274 1274 Scale 2-14-66 6 1203 1280 1280 Scale 2-14-67 6 1204 Frozen 1194 1194 ICEMANTM 2-14-68 6 1205 1190 1218 1190 Scale 2-14-69 6 1206 Frozen 1191 1191 ICEMANTm 2-15-61 6 1207 1220 1234 1220 Scale 2-15-62 6 1208 1167 1237 1167 Scale 2-15-63 6 1209 1327 1350 1327 Scale 2-15-64 6 1210 1318 1331 1318 Scale 2-15-65 6 1211 1168 1236 1168 Scale 2-15-66 6 1212 1253 1280 1253 Scale 2-15-67 6 1213 1206 1303 1206 Scale 2-15-68 6 1214 1295 1309 1295 Scale 2-15-69 6 1215 1181 1211 1188 Scale 2-16-6-1 6 1216 1221 1272 1221 Scale 2-16-6-2 6 1217 1193 1215 1193 Scale 2-16-63 6 1218 1196 1245 1196 Scale 2-16-64 6 1219 _ 1161 1238 1161 Scale 2-16-6-5 6 1220 1112; 1112 Scale 2-16-6-6 6 1221 115' 1213 1155 Scale 2-16-67 6 1222 1134 1167 1134 Scale 2-16-68 6 1223 134 1372 1348 Scale 2-16-69 6 1224 1341 1258 1341 Scale 2-17-61 6 1225 1349 1403 1349 Scale 2-17-6-2 6 1226 1326 1316 1326 Scale 2-17-6-3 6 1227 1165 1181 1165 Scale 2-17-4 6 1228 1262 1298 1262 Scale 2-17-6-5 6 1229 1134 1139 1134 Scale 2-17-6-6 6 1230 1204 1239 1204 Scale 2-17-67 6 1231 1184 1243 1184 Scale 2-17-68 6 1232 1106 1113 1106 Scale 2-17-69 6 1233 115( 116C 1150 Scale 2-18-61 6 1234 1149 1200 1149 Scale 2-18-62 6 1235 1266 1322 1266 Scale 2-18-63 6 1236 1240 1229 . 1240 Scale 2-18-64 6 1237 1314 1265 1314 Scale 2-18-65 6 1238 1284 1321 1284 Scale 2-18-66 6 1239 -1139 1179 1139 Scale 2-18-67 6 1240 1188 1240 1188 Scale 2-18-68 6 1241 1146 1178 1146 Scale 2-18-69 6 1242 1033 1211 1033 Scale 2-19-61 6 1243 ;1127 1143 1127 Scale 2-19-62 6 1244 1230 1289 1230 Scale 2-19-63 6 1245 128' 1334 1285 Scale TOPICAL REPORT ICUG-001, Revision 2 A-28 May 2003 DRAFT

2-19-6-4 6 1246 1196 1240 1196 Scale 2-19-6-5 6 1247 1190 l1190 Scale 2-19-66 6 1248 1184 1185 _ 1184 Scale 2-19-6-7 6 1249 1182 1235 1182 Scale 2-19-6-8 6 1250 1170 1222 1170 Scale 2-19-6-9 6 1251 1166 1197 _ 1166 Scale 2-20-6-1 6 1252 1203 1247 1203 Scale 2-20-6-2 6 1253 1194 1242 1194 Scale 2-20-6-3 6 1254 1339 1468 1339 Scale 2-20-6-4 6 1255 1180 1205 1180 Scale 2-20-6-5 6 1256 1149 1175 1149 Scale 2-20-6-6 6 1257 1282 1365 1282 Scale 2-20-6-7 6 1258 1192 1212 1192 Scale 2-20-6-8 6 1259 1162 1119 . 1162 Scale 2-20-6-9 6 1260 1118 1098 1118 Scale 2-21-6-1 6 1261 1187 1238 _ _ _ 1187 Scale 2-212 1262 1146 1136 1146 Scale 2-21-6-3 6 1263 1144 1225 1144 Scale 2-21-64 61264 1080 1152 1080 Scale 2-21__5 6 1265S1161 1161 Scale 2-21__6 6 1266 1168 1202 1168 Scale 2-21__7 6_1267 1110 1185 1110 Scale 2-21_ 8 6 - 1268 1081 1148 1081 Scale 2-21_ 9 6 1269 1106 1130 1106 Scale 2-22 1 _ 6 1270 1205 1217 1205 Scale 2-22-&2 6 1271 1304 1306 1304 Scale 2-22__3 6 1272 1312 1388 1312 Scale 2-22_ _ 6 1273 1342 1337 1342 Scale 2-22__5 6 _ 1274 1312 1315 1312 Scale 2-22-&6 6 1275 1225 1228 1225 Scale 2-22__7 6 1276 1380 1362 1380 Scale 2-22-&8 6 1277 1283 1304 1283 Scale 2-22__9 6 1278 1240 1252 1240 Scale 2-23__ _ 6 1279 1170 1196 1170 Scale 2-23__2 6 1280 1182 1199 1182 Scale 2-23-3 6 . 1281 1254 1286 1254 Scale 2-23-6_4 6 1282 1221 1245 1221 Scale 2-23-6-5 6 1283 1316 1314 1316 Scale 2-23-6-6 6 1284 1249 1261 1249 Scale 2-23__7 6 1285 1152 1153 1152 Scale 2-23-6-8 6 1286 1194 1240 1194 Scale 2-23-6-9 6 1287 1191 1182 1191 Scale 2-24-6-1 6 1288 1125 1114 1125 Scale 2-24-6-2 6 1289 1184 1154 1184 Scale 2-24-6-3 6 1290 1159 1169 1159 Scale 2-24-6-4 6 1291 Frozen 1209 1209 ICEMAN' 2-24__5 6 1292 Frozen 1198 1 19 8 ICEMANTM 2-24-6 6 1293 1242 1288 1242 Scale 2-24-6-7 6 1294 1230 1274 1230 Scale 2-24__8 6 _ 1295 1168 1210 1168 Scale 2-24-6-9 6 1296 11681 1188 1168 Scale 2-01-7-1 7 1297 1098 1111 _ __ 1098 Scale TOPICAL REPORT ICUG-001, Revision 2 A-29 May 2003 DRAFT

2-01-7-2 7 1298 1273 1239 1273 Scale 2-01-7-3 7 1299 1194 1160 1194 Scale 2-01-7-4 7 1300 1263 1211 1263 Scale 2-01-7-5 7 1301 1311 1308 1311 Scale 2-01-7-6 7 1302 1154 1166 1154 Scale 2-01-7-7 7 1303 1104 1076 _ 1104 Scale 2-01-7-8 7 1304 1162 1248 1162 Scale 2-01-7-9 7 1305 733 880 733 Scale 2-02-7-1 7 1306 940 907 940 Scale 2-02-7-2 7 1307 1059 1072 1059 Scale 2-02-7-3 7 1308 954 973 954 Scale 2-02-7-4 7 1309 978 1002 978 Scale 2-02-7-5 7 1310 1105 1103 1105 Scale 2-02-7-6 7 1311 994 1057 994 Scale 2-02-7-7 7 1312 993 1048 993 Scale 2-02-7-8 7 1313 866 964 866 Scale 2-02-7-9 7 1314 1129 1134 1129 Scale 2-03-7-1 7 1315 Frozen  : 1021 1021 Visual 2-03-7-2 7 1316 Frozen 956 956 Visual 2-03-7-3 7 1317 1391 1378 1391 Scale 2-03-7-4 7 1318 1218 1218 Scale 2-03-7-5 7 1319 1238 1234 1238 Scale 2-03-7-6 7 1320 1197 1192 1197 Scale 2-03-7-7 7 1321 1289 1233 1289 Scale 2-03-7-8 7 1322 1220 1208 1220 Scale 2-03-7-9 7 1323 1130 1100 1130 Scale 2404-7-1 7 1324 1434 1405 1434 Scale 2404-7-2 7 1325 1284 1333 1284 Scale 2-04-7-3 7 1326 1278 1300 1278 Scale 2-04-7-4 7 1327 Frozen 1201 1201 Visual 24-7-5 7 1328 1270 1102 1270 Scale 2404-7-6 7 1329 Frozen 1200 1200 ICEMANTm 2-04-7-7 7 1330 Frozen _ 1080 1080 Visual 2404-7-8 7 1331 1159 1167 1159 Scale 2-04-7-9 7 1332 1278 1315 1278 Scale 2-05-7-1 7 1333 1296 1282 1296 Scale 2-05-7-2 7 1334 1183 1200 1183 Scale 2-05-7-3 7 1335 1233 1233 Scale 2-05-7-4 7 1336 Frozen 1344 1344 Visual 2-05-7-5 7 1337 Frozen 1261 1261 Visual 2-05-7-6 7 1338 1322 1421 1322 Scale 2-05-7-7 7 1339 1204 1239 1204 Scale 2-05-7-8 7 1340 1276 1282 1276 Scale 2-05-7-9 7 1341 Frozen 1301 1301 Visual 2406-7-1 7 1342 Frozen 1277 1277 Visual 2466-7-2 7 1343 Frozen 1038 1038 Visual 240-7-3 7 1344 Frozen 1052 1052 Visual 2406-7-4 7 1345 Frozen . 1196 1196 Visual 2406-7-5 7 1346 Frozen _ _- 1258 1258 Visual 24067-6 7 1347 Frozen 1393 1393 Visual 2-7-7 7 1348 Frozen 1256 1256 Visual 2-06-7-8 7 1349 Frozen 1387 1387 Vial TOPICAL REPORT ICUG-001, Revision 2 A-30 May 2003 DRAFT

246-7-9 7 1350 Frozen_ 1011 1011 Visual 2-07-7-1 7 1351 Frozen 1053 1053 Visual 2-07-7-2 7 1352 1159 1144 _1159 Scale 2-07-7-3 7 1353 1127 1158 1127 Scale 2-07-7-4 7 1354 1187 1185 1187 Scale 2-07-7-5 7 1355 1175 1175 Scale 2-07-7-6 7 1356 1176 1192 1176 Scale 2-07-7-7 T 7 1357 - 1196 1231 _ 1196 Scale 2-07-7-8 7 1358 1.104 1126 1104 Scale 2-07-7-9 7 1359 1121 1121 Scale 2-08-7-1 7 1360 1174 1238 1174 Scale 2-08-7-2 7 1361 1230 1230 Scale 2-08-7-3 7 1362 1224 _1224 Scale 2-08-7-4 7 1363 1128 1128 Scale 2-08-7-5 7 1364 Frozen _ 1267 1267 Visual 2-08-7-6 7 1365 1184 1194 1184 Scale 2-08-7-7 7 1366 Frozen 1236 1236 ICEMANTm 2-08-7-8 7 ._1367 Frozen 1445 1445 Visual 2-08-7-9 7 1368

_ Frozen 1278 1278 Visual 2-09-7-1 7 1369 Frozen 1254 1254 Visual 2-09-7-2 7 1370 Frozen 1143 1143 Visual 2-09-7-3 7 1371 1193 1534 1193 Scale 2-09-74 7 1372 1238 1210 1238 Scale 2-09-7-5 7 1373 Frozen 1234 1234 Visual 2-09-7-6 7 1374 1241 1267 1241 Scale 2-09-7-7 7 1375 1151 1194 1151 Scale 2-09-7-8 7 1376 1180 1201 1180 Scale 2-09-7-9 7 1377 1241 1280 1241 Scale 2-10-7-1 7 1378 Frozen 1267 1267 Visual 2-10-7-2 7 1379 1047 1010 1047 Scale 2-10-7-3 7 1380 1268 1308 1268 Scale 2-10-7-4 7 1381 1176 1194 1176 Scale 2-10-7-5 7 1382 Frozen - 1247 1247 Visual 2-10-7-6 7 1383 1349 1346 1349 Scale 2-10-7-7 7 1384 Frozen 1411 1411 ICEMANTm 2-10-7-8 7 1385 Frozen 1440 1440 1 CEMANTm 2-10-7-9 7 1386 Frozen 1300 1300 Visual 2-11-7-1 7 1387 Frozen 1355 1355 Visual 2-11-7-2 7 1388 1359 1304 1359 Scale 2-11-7-3 7 1389 1285 1338 1285 Scale 2-11-7-4 7 1390 1411 1395 1411 Scale 2-11-7-5 7 1391 Frozen 1133 1133 Visual 2-11-7-6 7 1392 1192 1225 l1922_Scale 2-11-7-7 7 1393 1209 1225 1209 Scale 2-11-7-8 7 1394 1330 1333 1330 Scale 2-11-7-9 7 1395 1135 _ 1135 Scale 2-12-7-1 7 1396 Frozen 1378 1378 Visual 2-12-7-2 7 1397 Frozen 1267 1267 Visual 2-12-7-3 7 1398 Frozen 1345 1345 Visual 2-12-7-4 7 1399 Frozen 1356 1356 Visual 2-12-7-5 .7 1400 Frozen, 1376 1376 ICEMANTM 2-12-7-6 7 1401 1119 1214 _ 1119IScale TOPICAL REPORT ICUG-001, Revision 2 A-31 May 2003 DRAFT

2-12-7-7 7 1402 1310 1403 1310 Scale 2-12-7-8 7 1403 1116 1165 1116 Scale 2-12-7-9 7 1404 Frozen X 1145 1145 Visual 2-13-7-1 7 1405 Frozen 1276 1276 Visual 2-13-7-2 7 1406 Frozen 1231 1231 Visual 2-13-7-3 7 1407 1253 1291 1253 Scale 2-13-7-4 7 1408 1229 1242 1229 Scale 2-13-7-5 7 1409 Frozen 1356 1356 Visual 2-13-7-6 7 1410 Frozen _ 1388 1388 Visual 2-13-7-7 7 1411 Frozen 1230 1230 Visual 2-13-7-8 7 1412 Frozen 1079 1079 Visual 2-13-7-9 7 1413 Frozen 1256 1256 Visual 2-14-7-1 7 1414 1178 1237 1178 Scale 2-14-7-2 7 1415 1138 1205 1138 Scale 2-14-7-3 7 1416 Frozen 1046 1046 Visual 2-14-7-4 7 1417 Frozen 1136 1136 Visual 2-14-7-5 7 1418 Frozen 1262 1262 Visual 2-14-7-6 7 1419 Frozen 1323 1323 ICEMANX' 2-14-7-7 7 1420 Frozen -1156 1156 ICEMANTM 2-14-7-8 7 1421 Frozen 1739 1739 ICEMANTM 2-14-7-9 7 1422 Frozen 1473 1473 Visual 2-15-7-1 7 1423 1227 1222 1227 Scale 2-15-7-2 7 1424 Frozen 1104 1104 Visual 2-15-7-3 7 1425 Frozen 1069 1069 Visual 2-15-7-4 7 1426 Frozen 1009 1009 Visual 2-15-7-5 7 1427 Frozen 1378 1378 Visual 2-15-7-6 7 1428 Frozen 1405 1405 Visual 2-15-7-7 7 1429 1168 1181 1168 Scale 2-15-7-8 7 1430 1146 1211 1146 Scale 2-15-7-9 7 1431 1158 1199 1158 Scale 2-16-7-1 7 1432 1182 1229 1182 Scale 2-16-7-2 7 1433 1182 1320 1182 Scale 2-16-7-3 7 1434 1068 1115 1068 Scale 2-16-7-4 7 1435 1204 1230 1204 Scale 2-16-7-5 7 1436 Frozen 1172 1172 Visual 2-16-7-6 7 1437 Frozen 1054 1054 Visual 2-16-7-7 7 1438 Frozen 1191 ilgi ICEMAN1m 2-16-7-8 7 1439 1153 1308 1153 Scale 2-16-7-9 7 1440 Frozen 1132 1132 Visual 2-17-7-1 7 1441 Frozen 1167 1167 Visual 2-17-7-2 7 1442 Frozen 1255 1255 ICEMANTM 2-17-7-3 7 1443 1356 1371 1356 Scale 2-17-7-4 7 1444 1323 1312 1323 Scale 2-17-7-5 7 1445 Frozen 1321 1321 Visual 2-17-7-6 7 1446 1151 1151 Scale 2-17-7-7 7 1447 1222 1253 1222 Scale 2-17-7-8 7 1448 1303 1274 1303 Scale 2-17-7-9 7 1449 1040 1072 1040 Scale 2-18-7-1 7 1450 Frozen 1256 1256 Visual 2-18-7-2 7 1451 1180 1172 1180 Scale 2-18-7-3 7 1452 1331 1236, 1331 Scale 2-18-7-4 7 1453 1011 1054 1 1011 Scale TOPICAL REPORT ICUG-001, Revision 2 A-32 May 2003 DRAFT

2-18-7-5 7 1454 1129 1129 Scale 2-18-7-6 7 1455 1096 1158 C1096 Scale 2-18-7-7 7 1456 1335 1363 - 1335 Scale 2-18-7-8 7 1457 1198 1246 - 1198 Scale 2-18-7-9 7 1458 Frozen 1359 1359 Visual 2-19-7-1 7 1459 932 932 Scale 2-19-7-2 7 1460 _ _1115 1165 1115 Scale 2-19-7-3 7 1461 1180 1211 1180 Scale 2-19-7-4 7 1462 1202 1219 1202 Scale 2-19-7-5 7 1463 1163 1213 _ 1163 Scale 2-19-7-6 7 1464 1118 1123 1118 Scale 2-19-7-7 7 1465 Frozen 1134 1134 Visual 2-19-7-8 7 1466 Frozen 1209 1209 Visual 2-19-7-9 7 1467 Frozen 1128 1128 Visual 2-20-7-1 7 1468 1117 1152 1117 Scale 2-20-7-2 7 1469 1175 1177 1175 Scale 2-20-7-3 7 1470 1265 1331 1265 Scale 2-20-7-4 7 1471 954 990 954 Scale 2-20-7-5 7 1472 1132 1132 Scale 2-20-7-6 7 1473 1259 1228 1259 Scale 2-20-7-7 7 1474 914 1073 914 Scale 2-20-7-8 7 1475 1143 1194 1143 Scale 2-20-7-9 7 1476 1028 1028 Scale 2-21-7-1 7 1477 1070 1070 Scale 2-21-7-2 7 1478 1133 1081 1133 Scale 2-21-7-3 7 1479 1165 1230 1165 Scale 2-21-7-4 7 1480 1148 1224 1148 Scale 2-21-7-5 7 1481 1141 1141 Scale 2-21-7-6 7 1482 1218 1311 1218 Scale 2-21-7-7 7 1483 1228 1259 1228 Scale 2-21-7-8 7 1484 1093 1141 1093 Scale 2-21-7-9 7 1485 1007 1046 1070 1007 Scale 2-22-7-1 7 1486 1140 1155 1140 Scale 2-22-7-2 7 1487 1216 1216 Scale 2-22-7-3 7 1488 1412 1304 1412 Scale 2-22-7-4 7 1489 1243 1247 1243 Scale 2-22-7-5 7 1490 Frozen 1383 1383 Visual 2-22-7-6 7 1491 1325 1325 Scale 2-22-7-7 7 1492 1345 1367 1345 Scale 2-22-7-8 7 1493 Frozen 1034 1034 Visual 2-22-7-9 7 1494 1055 1055 Scale 2-23-7-1 7 1495 1100 1166 1100 Scale 2-23-7-2 7 1496 1145 1182 1145 Scale 2-23-7-3 7 1497 1294 1399 1294 Scale 2-23-7-4 7 1498 1284 1274 1284 Scale 2-23-7-5 7 1499 1200 1219 1200 Scale 2-23-7-6 7 1500 1270 1260 1270 Scale 2-23-7-7 7 1501 1212 1215 1212 Scale 2-23-7-8 7 1502 1295 1306 1295 Scale 2-23-7-9 7 1503 1185 1062 1185 Scale 2-24-7-1 7 1504 972 1002I 972 Scale 2-24-7-2 7 1505 1096 11481 1096 Scale TOPICAL REPORT ICUG-001, Revision 2 A-33 May 2003 DRAFT

2-24-7-3 7 1506 1130 1119 . 1130 Scale 2-24-74 7 1507 1189 1223 l 1189 Scale 2-24-7-5 7 1508 Frozen 1289 1289 Visual 2-24-7-6 7 1509 1249 1312 1249 Scale 2-24-7-7 7 1510 1292 1314 1292 Scale 2-24-7-8 7 1511 1192 1216 1192 Scale 2-24-7-9 7 1512 Frozen 1147 1147 Visual 2-014-1 8 1513 Frozen 1131 1131 Visual 2-01-8-2 8 1514 Frozen 1429 1429 Visual 2-01-8-3 8 1515 Frozen 1322 1322 Visual 2-01-8-4 8 1516 Frozen 1429 1429 Visual 2-01-8-5 8 1517 Frozen 1333 1333 Visual 2-01-8-6 8 1518 Frozen 1536 1536 Visual 2-01-8-7 8 1519 1090 1124 1141 1090 Scale 2-01-8-8 8 1520 770 764 1120 770 Scale 2-01-8-9 8 1521 853 843 1098 853 Scale 2-02-8-1 8 1522 995 1261 995 Scale 2-02-8-2 8 1523 858 810 858 Scale 2-02-8-3 8 1524 1067 1096 1216 1067 Scale 2-02-8-4 8 1525 866 1034 866 Scale 2-02-8-5 8 1526 1058 1039 1058 Scale 2-02-8-6 8 1527 946 1205 946 Scale 2-02-8-7 8 1528 - 838 _ _838 1082 838 Scale 2-02-8-8 8 1529 1165 1536 1165 Scale 2-02-8-9 8 1530 1026 1141 1026 Scale 2-038-1 8 1531 Frozen 1045 1045 Visual 2-03-8-2 8 1532 Frozen 1072 1072 Visual 2-03-8-3 8 1533 Frozen 1429 1429 Visual 2-03-84 8 1534 Frozen 1034 1034 Visual 2-03-8-5 8 1535 Frozen . 901 901 Visual 2-03-8-6 8 1536 Frozen _ 904 904 Visual 2-03-8-7 8 1537 1148 1077 1205 1148 Scale 2-03-8-8 8 1538 1314 1284 1360 1314 Scale 2-03-8-9 8 1539 1100 1370 1100 Scale 2-04-8-1 8 1540 Frozen . 1429 1429 Visual 2-04-8-2 8 1541 1381 1386 1381 Scale 2-04-8-3 8 1542 Frozen _ 1109 1109 Visual 2-04-84 8 1543 Frozen 1312 1312 Visual 2-04-8-5 8 1544 Frozen 1008 1008 Visual 2-04-8-6 8 1545 Frozen _ 1205 1205 Visual 2-04-8-7 8 1546 Frozen 1098 1098 Visual 2-04-8-8 8 1547 Frozen 1322 1322 Visual 2-04-8-9 8 1548 Frozen _ 984 984 Visual 2-05-8-1 8 1549 Frozen 999 999 Visual 2-05-8-2 8 1550 Frozen 1157 1157 Visual 2-05-8-3 8 1551 Frozen 1083 1083 Visual 2-05-84 8 1552 Frozen 1038 1038 Visual 2-05-8-5 8 1553 'Frozen 1215 1215 Visual 2-05-8-6 8 1554 Frozen 928 928 Visual 2-05-8-7 8 1555 Frozen 928 928 Visual 2-05-8-8 8 1556 Frozen 923 923 Visual 2-05-8-9 8 1557 Frozen I 1109 1109 Visual TOPICAL REPORT ICUG-001, Revision 2 A-34 May 2003 DRAFT

24068-1 8 1558 Frozen 1170 1170 Visual 2-06-8-2 8 1559 Frozen 1072 1072 Visual 2-06-8-3 8 _1560 Frozen 1180 1180 Visual 2-O68-4 8 1561 Frozen 1207 1207 Visual 2-06-8-5 8 1562 Frozen 1287 1287 Visual 2-068-6 8 1563 Frozen 1188 1188 Visual 24068-7 8 1564 Frozen 1287 1287 Visual 24068-8 8 1565 1382 1264 1382 Scale 2-068-9 8 1566 Frozen 989 989 Visual 2-07-8-1 8 1567 Frozen 956 956 Visual 2-07-8-2 8 1568 Frozen 1000 1000 Visual 2-07-8-3 8 1569 1321 1344 1418 1321 Scale 2-07-8-4 8 1570 Frozen -821 821 Visual 2-07-8-5 8 1571 Frozen 1358 1358 Visual 2-07-8-6 8 1572 Frozen 1386 1386 Visual 207-8-7 8 1573 1219 1286 1372 1219 Scale 2-07-8-8 8 1574 1254 1349 1384 1254 Scale 2-07-8-9 8 1575 1035 Ad 1075 1035 Scale 2-08-8-1 8 1576 Frozen 1281 1281 Visual 2-08-8-2 8 X 1577 Frozen 1434 1434 Visual 2-08-8-3 8 1578 Frozen 1483 1483 Visual 2-08-8-4 8 1579 Frozen 1081 1081 Visual 2-08-8-5 8 1580 Frozen 1254 1254 Visual 2-08-8-6 8 1581 Frozen 1289 1289 Visual 2-08-8-7 8 1582 Frozen 1173 1173 Visual 2-08-8 8 1583 Frozen 1536 1536 Visual 2-08-8-9 8 1584 Frozen 1115 1115 Visual 2-09-8-1 8 1585 Frozen 1330 1330 Visual 2-09-8-2 8 1586 Frozen 1250 1250 Visual 2-09-8-3 8 1587 Frozen 1192 1192 Visual 2-09-84 8 1588 1219 1116 1219 Scale 2-09-8-5 8 1589 Frozen 1416 1416 Visual 2-09-8-6 8 1590 Frozen 1383 1383 Visual 2-09-8-7 8 1591 Frozen 1156 1156 Visual 2-09-8-8 8 1592 Frozen 1098 1098 visual 2-09-8-9 8 1593 Frozen 1123 1123 Visual 2-10-8-1 8 1594 1240 1359 1409 1240 Scale 2-10-8-2 8 1595 1115 1237 1251 1115 Scale 2-10-8-3 8 1596 1115 1268 1274 1115 Scale 2-10-84 8 1597 1092 1131 1288 1092 Scale 2-10-8-5 8 1598 Frozen 1216 1216 Visual 2-10-8-6 8 1599 1143 1249 1293 1143 Scale 2-10-8-7 8 1600 -Frozen 1317 1317 Visual 2-10-8-8 8 1601 Frozen 1377 1377 Visual 2-10-8-9 8 1602 Frozen 1284 1284 Visual 2-11-8-1 8 1603 Frozen 1381 1381 Visual 2-11-8-2 8 1604 Frozen 1497 1497 Visual 2-11-8-3 8 1605 Frozen 1327 1327 Visual 2-11-8-4 8 1606 Frozen, 1376 1376 Visual 2-11-8-5 8 1607 Frozen 1376 1376 Visual 2-11-8-6 8 1608 Frozen 1367 1367 Visual 2-11-8-7 8 1609 Frozen 1345 1345 Visual TOPICAL REPORT ICUG-001, Revision 2 A-35 May 2003 DRAFT

2-11-8-8 8 1610 Frozen 1320 1320 Visual 2-11-8-9 8 1611 1086 1171 1216 1086 Scale 2-124-1 8 1612 Frozen 1323 1323 Visual 2-12-8-2 8 1613 Frozen 1416 1416 Visual 2-124-3 8 1614 Frozen 1418 1418 Visual 2-12-8-4 8 1615 Frozen 1340 1340 Visual 2-12-8-5 8 1616 Frozen 1394 1394 Visual 2-12-8-6 8 1617 Frozen 1447 1447 Visual 2-12-8-7 8 1618 1106 1186 1109 1106 Scale 2-12-8-8 8 1619 Frozen 1315 1315 Visual 2-12-8-9 8 1620 Frozen 1349 1349 Visual 2-13-8-1 8 1621 Frozen 1309 1309 Visual 2-13-8-2 8 1622 Frozen 1193 1193 Visual 2-13-8-3 8 1623 Frozen 1232 1232 Visual 2-13-8-4 8 1624 1159 1271 1189 1159 Scale 2-13-8-S 8 1625 Frozen 1362 1362 Visual 2-13-8-6 8 1626 Frozen 1367 1367 Visual 2-13-8-7 8 1627 Frozen 1357 1357 Visual 2-13-8-8 8 1628 Frozen 1465 1465 Visual 2-13-8-9 8 1629 Frozen 1422 1422 Visual 2-14-8-1 8 1630 Frozen 1202 1202 Visual 2-14-8-2 8 1631 1350 1329 1309 1350 Scale 2-14-8-3 8 1632 Frozen 1199 1199 Visual 2-14-8-4 8 1633 Frozen 1161 1161 Visual 2-14-8-5 8 1634 Frozen 1181 1181 Visual 2-14-8-6 8 1635 Frozen 1411 1411 Visual 2-14-8-7 8 1636 1330 1478 1388 1330 Scale 2-14-8-8 8 1637 Frozen _ 1153 1153 Visual 2-14-8-9 8 1638 Frozen 1296 1296 Visual 2-15-8-1 8 1639 Frozen 1159 1159 Visual 2-15-8-2 8 1640 Frozen 1477 1477 Visual 2-15-8-3 8 1641 Frozen 1158 1158 Visual 2-15-8-4 8 1642 Frozen 1117 1117 Visual 2-15-8-5 8 1643 Frozen 1102 1102 Visual 2-15-8-6 8 1644 Frozen 1127 1127 Visual 2-15-8-7 8 1645 Frozen 1260 1260 Visual 2-15-8-8 8 1646 1156 1257 1242 1156 Scale 2-15-8-9 8 1647 Frozen 1167 1167 Visual 2-16-8-1 8 _ _ 1648 Frozen 1191 1191 Visual 2-16-8-2 8 1649 Frozen 1376 1376 Visual 2-16-8-3 8 1650 1202 1176 1189 1202 Scale 2-16-8-4 8 1651 Frozen _ __ 1143

_1143 _Vsual 2-16-8-5 8 1652 Frozen 1253 1253 Visual 2-16-8-6 8 1653 Frozen 1367 1367 Visual 2-16-8-7 8 1654 Frozen 1132 1132 Visual 2-16-8-8 8 1655 Frozen 1181 181SVisual 2-16-8-9 8 1656 Frozen 989 989 Visual 2-17-8-1 8 1657 Frozen 1322 1322 Visual 2-17-8-2 8 1658 Frozen 1408 1408 Visual 2-17-8-3 8 1659 Frozen. 1107 1107 Visua 2-17-8-4 8 1660 Frozen 1378 1378 Visual 2-17-8-5 8 1661 Frozenr 803 803 Visua TOPICAL REPORT ICUG-001, Revision 2 A-36 May 2003 DRAFT

2-17-8-6 8 1662 Frozen 1363 1363 Visual 2-17-8-7 8 _ 1663 1086 1108 1196 1086 Scale 2-17-8-8 8 1664 Frozen 1406 1406 Visual 2-17-8-9 8 1665 1202 1411 1202 Scale 2-18-8-1 8 1666 1076 1221 1076 Scale 2-18-8-2 8 1667 Frozen 1397 1397 Visual 2-18-8-3 8 1668 1140 1208 1140 Scale 2-18-8-4 8 1669 1286 1314 1359 1286 Scale 2-18-8-5 8 1670 Frozen 1058 1058 Visual 2-18-8-6 8 1671 Frozen 1274 1274 Visual 2-18-8-7 8 1672 Frozen 1261 1261 Visual 2-18-8-8 8 1673 Frozen 1044 1044 Visual 2-18-8-9 8 1674 Frozen 1010 1010 Visual 2-19-8-1 8 1675 1130 1259 1370 1130 Scale 2-19-8-2 8 1676 Frozen 1319 _ 1319 Visual 2-19-8-3 8 . 1677 Frozen 1223 1223 Visual 2-19-8-4 8 1678 Frozen 1131 1131 Visual 2-19-8-5 8 1679 Frozen 1184 1184 Visual 2-19-8-6 8 1680 Frozen 1487 1487 Visual 2-19-8-7 8 1681 Frozen 1004 1004 Visual 2-19-8-8 8 1682 Frozen 994 994 Visual 2-19-8-9 8 1683 Frozen 1221 1221 Visual 2-20-8-1 8 1684 Frozen 1192 1192 Visual 2-20-8-2 8 1685 Frozen 1231 1210 1231 ICEMANT 2-20-8-3 8 1686 1275 1311 1377 1275 Scale 2-20-8-4 8 _ _ 1687 1186 1194 1219 1186 Scale 2-20-8-5 8 1688 1071 1177 1073 1071 Scale 2-20-8-6 8 1689 1323 1010 1438 1323 Scale 2-20-8-7 8 _ _ _ 1690 1126 1164 1274 1126 Scale 2-20-8-8 8 1691 772 817 817 772 Scale 2-20-8-9 8 1692 972 971 1447 972 Scale 2-21-8-1 8 _____1693 Frozen 862 862 Visual 2-21-8-2 8 1694 1062 1189 1369 1062 Scale 2-21-8-3 8 1695 1181 1294 1288 1181 Scale 2-21-8-4 8 1696 Frozen 992 992 Visual 2-21-8-S 8 1697 Frozen 1154 1154 Visual 2-21-8-6 8 1698 Frozen 1093 1093 Visual 2-21-8-7 8 1699 Frozen 1207 1207 Visual 2-21-8-8 8 1700 Frozen 1409 1409 Visual 2-21-8-9 8 1701 Frozen 1137 1137 Visual 2-22-8-1 8 1702 Frozen 1448 1448 Visual 2-22-8-2 8 1703 1200 1216 1068 1200 Scale 2-22-8-3 8 1704 1465 1524 1296 1465 Scale 2-22-8-4 8 1705 Frozen 1269 1269 Visual 2-22-8-5 8 1706 Frozen 1483 1483 Visual 2-22-8-6 8 1707 Frozen 1225 1225 Visual 2-22-8-7 8 1708 Frozen 1244 1075 1244 ICEMANTM 2-22-8-8 8 1709 1449 1391 1487 1449 Scale 2-22-8-9 8 _ 1710 Frozen 1216 1216 Visual 2-23-8-1 8 _1711 Frozen 1487 1487 Visual 2-23-8-2 8 11712 Frozen 1085 1085 Visual 2-23-8-3 8 1713 Frozen . 1225 1225 Visual TOPICAL REPORT ICUG-001, Revision 2 A-37 May 2003 DRAFT

2-23-8-4 8 1714 Frozen l 1166 1166 Visual 2-23-8-5 8 1715 1495 42 1417 1495 Scale 2-23-8-6 8 1716 1236 1253 1324 1236 Scale 2-23-8-7 8 = 1717 1284 1273 1317 1284 Scale 2-23-8-8 8 1718 Frozen 1178 1178 Visual 2-23-8-9 8 1719 Frozen 1016 1016 Visual 2-24-8-1 8_ 1720 894 .1267 1116 _ 894 Scale 2-24-8-2 8 1721 1112 1238 1112 Scale 2-24-8-3 8 1722 1116 1169 1254 1116 Scale 2-24-8-4 8 1723 Frozen 1089 1089 Visual 2-24-8-5 8 1724 Frozen 1292 1292 Visual 2-24-8-6 8 1725 Frozen 1135 1135 Visual 2-24-8-7 8 1726 Frozen 1231 1231 Visual 2-24-8-8 8 1727 Frozen 1406 1406 Visual 2-24-8-9 8 1728 Frozen 1250 1250 Visual 2-01-9-1 9 1729 Frozen 1056 1056 Visual 2-01-9-2 9 1730 Frozen 1536 1536 Visual 2-01-9-3 9 1731 Frozen 1536 1536 Visual 2-01-94 9 1732 Frozen i 1536 1536 Visual 2-01-9-5 9 1733 Frozen 1322 1322 Visual 2-01-9-6 9 1734 Frozen 704 704 Visual 2-01-9-7 9 1735 Frozen 986 986 Visual 2-01-9-8 9 1736 856 1174 856 Scale 2-01-9-9 9 1737 828 1114 688 828 Scale 2-02-9-1 9 1738 Frozen _ 1037 1037 Visual 2-02-9-2 9 1739 Frozen 1376 1376 Visual 2-02-9-3 9 1740 Frozen ________1104 1104 Visual 2-02-9-4 9 1741 Frozen 1333 1333 Visual 2-02-9-5 9 1742 Frozen 840 840 Visual 2-02-9-6 9 1743 Frozen 938 938 Visual 2-02-9-7 9 1744 Frozen 880 880 Visual 2-02-9-8 9 1745 Frozen _ 1451 1451 Visual 2-02-9-9 9 1746 Frozen _ 1072 1072 Visual 2-03-9-1 9 1747 Frozen 1139 1139 Visual 2-03-9-2 9 1748 Frozen 1078 1078 Visual 2-03-9-3 9 1749 Frozen 1232 1232 Visual 2-03-9-4 9 1750 Frozen _ 1370 1370 Visual 2-03-9-5 9 1751 Frozen 1345 1345 Visual 2-03-9-6 9 1752 Frozen _ 1464 1464 Visual 2-03-9-7 9 1753 Frozen 1376 1376 Visual 2-03-9-8 9 1754 Frozen 1178 1178 Visual 2-03-9-9 9 1755 Frozen 1298 1298 Visual 2-04-9-1 9 1756 Frozen 1370 1370 Visual 2-04-9-2 9 1757 1230 1333 1230 Scale 2-04-9-3 9 1758 Frozen 1226 1226 Visual 2-04-9-4 9 1759 Frozen 1195 1195 Visual 2-04-9-5 9 1760 Frozen 1110 II 10 Visual 2-04-9-6 9 1761 Frozen 1216 1216 Visual 2-04-9-7 9 1762 Frozen 1024 1024 Visual 2-04-9-8 .9 .1763 Frozen 1141 1_141 Visual 2-04-9-9 9 1764 Frozen 1154_ 1154 Visual 2-05-9-1 9 1765 Frozenr 1500_ 1500 Visual TOPICAL REPORT ICUG-001, Revision 2 A-38 May 2003 DRAFT

2-05-9-2 9 1766 Frozen . 1307 1307 Visual 2-05-9-3 9 1767 Frozen 1367 1367 Visual 2-05-9-4 9 1768 Frozen 1191 1191 Visual 2-05-9-5 9 1769 Frozen 1335 1335 Visual 2-05-9-6 9 1770 Frozen 976 976 Visual 2-05-9-7 9 1771 1166 1358 1166 Scale 2-05-9-8 9 1772 Frozen 1019 1019 Visual 2-05-9-9 9 1773 Frozen 1298 1298 Visual 2-06-9-1 9 1774 Frozen 1131 1131 Visual 2-06-9-2 9 1775 Frozen 1500 1500 Visual 2-06-9-3 9 1776 Frozen 1260 1260 Visual 2-06-9-4 9 1777 Frozen 1507 1507 Visual 2-06-9-5 9 1778 Frozen 1358 135 8 Visual 2-06-9-6 9 1779 Frozen 1416 1416 Visual 2-06-9-7 9 1780 Frozen 1504 1504 Visual 2-06-9-8 9 1781 Frozen 1163 1163 Visual 2-06-9-9 9 1782 Frozen 1188 1188 Visual 2-07-9-1 9 1783 Frozen 1234 1234 Visual 2-07-9-2 9 1784 Frozen 1497 1497 Visual 2-07-9-3 9 1785 Frozen 1289 1289 Visual 2-07-9-4 9 1786 Frozen 923 923 Visual 2-07-9-5 9 1787 Frozen 1500 1500 Visual 2-07-9-6 9 1788 Frozen 1341 1341 Visual 2-07-9-7 9 1789 Frozen 1161 1161 Visual 2-07-9-8 9 1790 Frozen _ 1428 1428 Visuai 2-07-9-9 9 1791 Frozen 1114 14 Visual 2-08-9-1 9 1792 Frozen 1448 1448 Visual 2-08-9-2 9 1793 Frozen 937 937 Visual 2-08-9-3 9 1794 1498 1465 1498 Scale 2-08-94 9 1795 Frozen . 1329 1329 Visual 2-08-9-5 9 1796 Frozen 1378 1378 Visual 2-08-9-6 9 1797 Frozen 1399 1399 Visual 2-08-9-7 9 1798 Frozen . 1536 1_536 Visual 2-08-9-8 9 1799 Frozen 1448 1448 Visual 2-08-9-9 9 1800 Frozen 1536 1536 Visual 2-09-9-1 9 1801 Frozen 1447 1447 Visual 2-09-9-2 9 1802 Frozen 112 1 112_1 Visual 2-09-9-3 9 1803 1286 1360 1287 1286 Scale 2-09-9-4 9 1804 Frozen 1362 1_362 Visual 2-09-9-5 9 1805 Frozen 1504 1504 Visual 2-09-9-6 9 1806 Frozen 1259 1259 Visual 2-09-9-7 9 1807 Frozen _ 1442 1442 Visual 2-09-9-8 9 1808 Frozen 1536 1536 Visual 2-09-9-9 9 1809 Frozen 1333 1333 Visual 2-10-9-1 9 1810 Frozen 143_8 1438 Visual 2-10-9-2 9 1811 1079 1354 1269 1079 Scale 2-10-9-3 9 1812 935 1255 935 Scale 2-10-94 9 1813 Frozen 1045 1045 Visual 2-10-9-5 9 1814 Frozen 1283 1283 Visual 2-10-9-6 9 1815 Frozen 1435 1435 Visual 2-10-9-7 9 1816 Frozen 1363 1363 Visual 2-10-9-8 9 1817 Frozen1394 1394 Visusl TOPICAL REPORT ICUG-001, Revision 2 A-39 May 2003 DRAFT

2-10-9-9 9 1818 Frozen 1358 1358 Visual 2-11-9-1 9 1819 Frozen 1435 1435 Visual 2-11-9-2 9 1820 Frozen 1452 1452 Visual 2-11-9-3 9 1821 Frozen 1426 1426 Visual 2-11-9-4 9 1822 Frozen 1404 1404 Visual 2-11-9-5 9 1823 Frozen 1429 1429 Visual 2-11-9-6 9 1824 Frozen 1435 1435 Visual 2-11-9-7 9 1825 Frozen 1477 1477 Visual 2-11-9-8 9 1826 Frozen 1411 1411 Visual 2-11-9-9 9 1827 Frozen 1394 1394 Visual 2-12-9-1 9 1828 Frozen 1345 1345 Visual 2-12-9-2 9 1829 Frozen . 1483 1483 Visual 2-12-9-3 9 1830 - Frozen 1411 1411 Visual 2-12-9-4 9 1831 Frozen 1458 1458 Visual 2-12-9-5 9 1832 _Frozen1370 1370 Visual 2-12-9-6 9 1833 Frozen 1233 1233 Visual 2-12-9-7 9 1834 - Frozen _ 1447 1447 Visual 2-12-9-8 9 1835 Frozen 1339 1339 Visual 2-12-9-9 9 1836 Frozen 1536 1536 Visual 2-13-9-1 9 1837 Frozen 1305 1305 Visual 2-13-9-2 9 1838 Frozen 1388 1388 Visual 2-13-9-3 9 1839 Frozen 1320 1320 Visual 2-13-9-4 9 1840 Frozen 1248 1248 Visual 2-13-9-5 9 1841 Frozen 1406 1406 Visual 2-13-9-6 9 1842 1229 1213 1229 Scale 2-13-9-7 9 1843 Frozen 1244 1244 Visual 2-13-9-8 9 1844 Frozen 1447 1447 Visual 2-13-9-9 9 1845 Frozen 1394 1394 Visual 2-14-9-1 9 1846 Frozen 1291 1291 Visual 2-14-9-2 9 1847 Frozen 1536 1536 Visual 2-14-9-3 9 1848 1334 1402 1334 Scale 2-14-9-4 9 1849 Frozen 1500 1500 Visual 2-14-9-S 9 1850 Frozen 1500 1500 Visual 2-14-9-6 9 1851 Frozen 1443 1443 Visual 2-14-9-7 9 1852 Frozen 1424 1424 Visual 2-14-9-8 9 1853 Frozen 1497 1497 Visual 2-14-9-9 9 1854 Frozen 1447 1447 Visual 2-15-9-1 9 1855 Frozen 1411 1411 Visual 2-15-9-2 9 1856 Frozen 1467 1467 Visual 2-15-9-3 9 1857 Frozen 1463 1463 Visual 2-15-9-4 9 1858 Frozen 1291 1291 Visual 2-15-9-5 9 1859 Frozen 1239 1239 Visual 2-15-9-6 9 1860 Frozen 1398 1398 Visual 2-15-9-7 9 1861 1219 1245 1298 1219 Scale 2-15-9-8 9 1862 1330 1435 1330 Scale 2-15-9-9 9 1863 Frozen 1362 1362 Visual 2-16-9-1 9 1864 Frozen 1003 1003 Visual 2-16-9-2 9 1865 Frozen 1041 1041 Visual 2-16-9-3 9 1866 1095 1072 1095 Scale 2-16-9-4 9 1867 Frozen 1417 1417 Visual 2-16-9-5 9 11868 Frozen 1392 1392 Visual 2-16-9-6 9 1869 Frozen_ 1497 1497 Visual TOPICAL REPORT ICUG-001. Revision 2 A40 May 2003 DRAFT

2-16-9-7 9 1870 Frozen 1276 1276 Visual 2-16-9-8 9 1871 Frozen . 1387 1387 Visual 2-16-9-9 9 1872 Frozen 1394 1394 Visual 2-17-9-1 9 1873 Frozen _ 1239 1239 Visual 2-17-9-2 9 1874 Frozen 1455 1455 Visual 2-17-9-3 9 1875 Frozen 1414 1414 Visual 2-17-9-4 9 1876 Frozen 1086 1086 Visual 2-17-9-5 9 1877 Frozen 1339 1339 Visual 2-17-9-6 9 1878 Frozen 1304 1304 Visual 2-17-9-7 9 1879 Frozen 1497 1497 Visual 2-17-9-8 9 1880 Frozen 1117 1117 Visual 2-17-9-9 9 1881 Frozen 1035 1035 Visual 2-18-9-1 9 1882 Frozen 1058 1058 Visual 2-18-9-2 9 1883 Frozen 1161 1319 1161 ICEMANTm 2-18-9-3 9 1884 1100 1345 1100 Scale 2-18-9-4 9 1885 Frozen 1053 1053 Visual 2-18-9-5 9 1886 Frozen 1434 1434 Visual 2-18-9-6 9 1887 Frozen 1260 1260 Visual 2-18-9-7 9 1888 Frozen X 1388 1388 Visual 2-18-9-8 9 1889 Frozen 1368 1368 Visual 2-18-9-9 9 1890 Frozen 1483 1483 Visual 2-19-9-1 9 1891 Frozen 1429 1429 Visual 2-19-9-2 9 1892 Frozen 1356 1356 Visual 2-19-9-3 9 1893 Frozen 1294 1294 Visual 2-19-9-4 9 1894 -Frozen 1120 1120 Visual 2-19-9-5 9 1895 Frozen 1507 1507 Visual 2-19-9-6 9 1896 Frozen 1075 1075 Visual 2-19-9-7 9 1897 Frozen 1098 1098 Visual 2-19-9-8 9 1898 Frozen 1116 1116 Visual 2-19-9-9 9 1899 Frozen 1497 1497 Visual 2-20-9-1 9 1900 Frozen 1301 1497 1301 ICEMANTM 2-20-9-2 9 1901 Frozen 1399 1399 Visual 2-20-9-3 9 1902 1175 1340 1175 Scale 2-20-9-4 9 1903 1080 1536 1080 Scale 2-20-9-5 9 1904 Frozen 1102 1102 Visual 2-20-9-6 9 1905 902 934 1279 902 Scale 2-20-9-7 9 1906 1040 1214 1047 1040 Scale 2-20-9-8 9 1907 Frozen 1365 1365 Visual 2-20-9-9 9 1908 Frozen 1204 1204 Visual 2-21-9-1 9 1909 Frozen 1243 1243 Visual 2-21-9-2 9 1910 Frozen 1429 1429 Visual 2-21-9-3 9 1911 791 1088 791 Scale 2-21-9-4 9 1912 Frozen 1129 1129 Visual 2-21-9-5 9 1913 Frozen 1424 1424 Visual 2-21-9-6 9 1914 Frozen 1448 1448 Visual 2-21-9-7 9 1915 1230 1361 1448 1230 Scale 2-21-9-8 9 1916 Frozen 1401 1401 Visual 2-21-9-9 1917 Frozen 1013 1013 Visual 2-22-9-1 9 1918 Frozen 1203 1203 Visual 2-22-9-2 9 1919 Frozen 1380 1380 Visual 2-22-9-3 9 1920 1242 15361 1242 Scale 2-22-9-4 9 1921 Frozen _ 1309 1309 Visual TOPICAL REPORT ICUG-001, Revision 2 A-41 May 2003 DRAFT

2-22-9-5 9 1922 Frozen l 1451 1451 Visual 2-22-9-6 9 1923 Frozen 1314 1314 Visual 2-22-9-7 9 1924 Frozen 1195 1195 Visual 2-22-9-8 9 1925 Frozen 1340 1340 Visual 2-22-9-9 9 1926 Frozen 1307 1307 Visual 2-23-9-1 9 1927 Frozen 1256 1256 Visual 2-23-9-2 9 1928 Frozen 1361 1361 Visual 2-23-9-3 9 1929 Frozen 1299 1299 Visual 2-23-9-4 9 1930 Frozen 1390 1390 Visual 2-23-9-5 9 1931 Frozen 1358 1358 Visual 2-23-9-6 9 1932 Frozen 1297 1297 Visual 2-23-9-7 9 1933 Frozen 1183 1183 Visual 2-23-9-8 9 1934 Frozen 1159 1159 Visual 2-23-9-9 9 1935 Frozen 1318 1318 Visual 2-24-9-1 9 1936 694 727 1035 694 Scale 2-24-9-2 9 1937 1240 1307 1240 Scale 2-24-9-3 9 1938 1018 1026 1065 1018 Scale 2-24-9-4 9 1939 Frozen 1349 1349 Visual 2-24-9-5 9 1940 Frozen 1390 1390 Visual 2-24-9-6 9 1941 Frozen 1287 128 Visual 2-24-9-7 9 1942 Frozen, 1458 1458,Visual 2-24-9-8 9 1943 Frozen 1177 1177 Visual 2-24-9-9 9 1944 Frozen _ 1363 1363 Visual Mean (lb) 1274.1 1310.3 1266.6 1278.4 Standard 146.0 145.2 157.5 154.1 Deviation (lb)

Number of 1230 1175 737 1944 Data Points _ :X Total (Ib) I _ _ _ 2,485,268 TOPICAL REPORT ICUG-001, Revision 2 A-42 May 2003 DRAFT

Table A-2. Ice Mass Sample Group (from parent population in Table A-1)

TOPICAL REPORT ICUG-001, Revision 2 A-43 May 2003 DRAFT

7 BasketNumber Row Column Bay Radial Sample- Mass Method

_______________ ___ __ - Group

. SZone (lb) __

124 1 7 14 C 1 1350 Visual 158 1 5 18 C 2 1325 Visual 127 1 1 15 C 3 1532 Scale 26 1 8 03 C 4 1050 Visual 92 12 11 51322 Visual 178 i 7 20 C 6 1538 ICEMAN TM 86 I 5 10 C 7 1678 ICEMANTM 163 1 1 19 C 8 1101 Visual 105 1 6 12 C 9 1356 Scale 171 i 9 19 C 10 1278 Visual 195 1 6 22 C I 1500 Visual 73 i 1 09 C 12 1365 Visual 29 i 2 04 C 13 1884 Scale 14 1 5 02 C 14 1145 Visual 22 1 4 03 C 15 1300 Visual 149 1 5 17 C 16 1400 Visual 265 2 4 06 C 1 1500 Visual 334 2 1 14 C 2 1468 ICEMANTM 337 2 4 14 C 3 1433 ICEMANTM 425 2 2 24 C 4 1198 Scale 386 2 8 19 C 5 1412 Visual 264 2 3 06 C 6 1643 ICEMANTM 221 2 5 01 C 7 1374 Scale 322 2 7 12 C 8 1485 Scale 364 2 4 17 C 9 1283 Visual 226 2 1 02 C 10 1100 Visual 391 2 4 20 C 11 1383 Scale 379 2 1 19 C 12 1199 Visual 310 2 4 11 C 13 1356 Visual 292 2 4 09 C 14 1245 Visual 332 2 8 13 C 15 1436 Scale 287 2 8 08 C 16 1347 Scale 478 3 1 06 C 1 1516 ICEMANTm 492 3 6 07 C 2 1478 Scale 628 3 7 22 C 3 1413 Scale 487 3 1 07 C 4 1450 Scale 463 3 4 04 C 5 1426 Scale 456 3 6 03 C 6 1506 Scale 605 3 2 20 C 7 1421 Scale 450 3 9 02 C 8 1329 Scale 638 3 8 23 C 9 1458 Scale 542 3 2 13 C 10 1334 Scale 620 3 8 21 C 11 1367 Scale 501 3 6 08 C 12 1392 Scale 625 3 4 22 C 13 1503 Scale 464 3 5 04 C 14 1415 Scale TOPICAL REPORT ICUG-001, Revision 2 A-44 May 2003 DRAFT

519 3 6 10 C 15 1438 Scale 534 3 3 12 C 16 1425 Scale 811 4 1 19 B- 1 1411 Scale 777 4 3 15 B 2 1218 Scale 823 4 4 20 B 3 1243 Scale 756 4 9 12 B 4 1298 Scale 842 4 5 22 B 5 1345 Scale 688 4 4 05 B 6 1264 Scale 725 4 5 09 B 7 1255 Scale 651 4 3 01 B 8 1306 Scale 702 4 9 06 B 9 1291 Scale 746 4 8 11 B 10 1397 Scale 714 4 3 08 B 11 1207 Scale 788 4 5 16 B 12 1247 Scale 805 4 4 18 B 13 1211 Scale 650 4 2 01 B 14 1320 Scale 778 4 4 15 B 15 1202 Scale 706 4 4 07 B 16 1344 Scale 883 5 1 03 B 1 1366 Scale 867 5 3 01 B 2 1248 Scale 935 5 8 08 B 3 1195 Scale 994 5 4 15 B 4 1265 Scale 936 5 9 08 B 5 1326 Scale 975 5 3 13 B 6 1329 Scale 990 5 9 14 B 7 1233 Visual 934 5 7 08 B 8 1170 Scale 917 5 8 06 B 9 1233 Scale 1022 5 5 18 B 10 1244 Scale 952 5 7 10 B 11 1305 Scale 887 5 5 03 B 12 1314 Scale 987 5 6 14 B 13 1246 Scale 898 5 7 04 B 14 1190 scale 939 5 3 09 B 15 1185 Scale 1059 5 6 22 B 16 1207 Scale 1183 6 4 12 B 1 1258 Scale 1244 6 2 19 B 2 1230 Scale 1146 6 3 08 B 3 1159 Scale 1181 6 2 12 B 4 1225 Scale 1267 6 7 21 B 5 1110 Scale 1258 6 7 20 B 6 1192 Scale 1136 6 2 07 B 7 1183 Scale 1167 6 6 10 B 8 1363 Scale 1132 6 7 06 B 9 1338 Scale 1173 6 3 11 B 10 1212 Scale 1121 6 5 05 B 11 1218 Scale 1267 6 7 21 B 12 1110 Scale 1256 6 5 20 B 13 1149 Scale 1175 6 5 11 B 14 1288 Scale 1163 6 2 10 B 15 1198 Scale TOPICAL REPORT ICUG-001, Revision 2 A-45 May 2003 DRAFT

1273 6 4 22 B 16 1342 Scale 1490 7 5 22 A 1 1383 Visual 1510 7 7 24 A 2 1292 Scale 1342 7 1 06 3 1277 Visual 1487 7 2 22 A 4 1216 Scale 1397 7 2 12 A 5 1267 Visual 1378 7 1 10 A 6 1267 Visual 1498 7 4 23 A ,7 1284 Scale 1436 7 5 16 A 8 1172 Visual 1368 7 9 08 A 9 1278 Visual 1301 7 5 01 -A 10 1311 Scale 1371 7 3 09 A 11 1193 Scale 1506 7 3 24 A 12 1130 Scale 1323 7 9 03 A 13 1130 Scale 1466 7 8 19 A 14 1209 Visual 1421 7 8 14 A 15 1739 ICEMANrm 1367 7 8 08 A 16 1445 Visual 1604 8 2 11 A 1 1497 Visual 1625 8 5 13 A 2 1362 Visual 1709 8 8 22 A 3 1449 Scale 1664 8 8 17 A 4 1406 Visual 1536 8 6 03 A 5 904 Visual 1571 8 5 07 A 6 1358 Visual 1528 8 7 02 A 7 838 Scale 1660 8 4 17 A 8 1378 Visual 1520 8 8 01 A 9 770 Scale 1636 8 7 14 A 10 1330 Scale 1650 8 3 16 A 11 1202 Scale 1514 8 2 01 A 12 1429 Visual 1634 8 5 14 A 13 1181 Visual 1519 8 7 01 A 14 1090 Scale 1606 8 4 11 A 15 1376 Visual 1594 8 1 10 A 16 1240 Scale 1803 9 3 09 A 1 1286 Scale 1909 9 1 21 A 2 1243 Visual 1767 9 3 05 A 3 1367 Visual 1743 9 6 02 A 4 938 Visual 1802 9 2 09 A 5 1121 Visual 1731 9 3 01 A 6 1536 Visual 1934 9 8 23 A 7 1159 Visual 1886 9 5 18 A 8 1434 Visual 1939 9 4 24 A 9 1349 Visual 1932 9 6 23 A 10 1297 Visual 1846 9 1 14 A 11 1291 Visual 1757 9 2 04 A 12 1230 Scale 1875 9 3 17 A 13 1414 Visual 1905 9 6 20 A 14 902 Scale 1799 9 08 A15 1448 Visual 1775 9 2 06 A 16 1500 Visual TOPICAL REPORT ICUG-001, Revision 2 A-46 May 2003 DRAFT

Table A-3. Example Calculations (for Table A-2 sample group)

I TOPICAL REPORT ICUG-001, Revision 2 A47 May 2003 DRAFT

oStratified-Sampling _ _______ :_____:____: _

Sample Sample Mean, Standard No. of Data No. of Data No. of Data Total 95% Total Ice Bed Mass Is Size Group(s) X (lb) Deviation, s Points from Points from Points from Error of Conf. at least (lb)

(lb) Scale ICEMANTm VISUAL the mean Mean (lb) 36 1.4 1321 133 21 3 12 61.4 1259 2,447,985 72 1-8 1314 156 40 6 26 46.5 1267 2,463,030 90 1-10 1305 154 52 6 32 41.0 1264 2,456,726 108 1-12 1301 147 65 6 37 36.2 1265 2,458,818 144 1-16 1305 155 88 7 49 31.8 1273 2,475,670 tratified Sampling:- Three Sequential Rows in each Radial Zone - ---  :  :

Sample Sample Radial Mean, X Standard No. of Data No. of Data No. of Total 95% Total Ice size Group(s) Zone (lb) Deviation, s Points from Points from Data Error of Conf. Bed Mass (lb) Scale ICEMANT' Points the mean Mean (lb) is at least from (lb) (lb)

VISUAL 36 Total 2,372,078 12 1-4 C 1393 1443.4 513 4 117.00 12761 12 1-4 B 1260 70.2 12 j 0 0 37.1 j 1223 12 1-4 A 1310 144.0 4 0 8 147.3 11162 l 72 total 2,410,530 24 24 24 1-8 1-8 1-8 C

B A

11415 1258 1268 147.2 73.8 178.0 1 11 23 6

f 1 6 0

0 7

1 18 76.8 33.8 110.0 113381 12241 1158 90 total _ _ 2,409,810 30 1-10 C 1392 1 147.3 1 14 l 6 l 10 1 70.6 1 1321 l 30 1-10 B 1 1264 1 72.9 1 29 0 11 28.5 1235 30 1-10 A 1 1259 184.5 1 9 0 21 96.4 1162 LL8 2,417,634 36 1-12 C [ 1388 7 139.3 7 17 [ 6 13 1 64.2 7 1324 36 1-12 B 1 1259 73.0 35 [ 0 11 25.1 1233 36 1-12 A 1257 172.6 13 0 23 83.0 l 1174 l 111 2,439,746 48 1-16 jC 1 1269 185.41 24 6 181 63.0 1206 _

48 1-161 B l 1254 71.2 47 0 11 20.3 1234 48 1-16 lA 1393 148.3 17 1 l 30 67.6 1325 _

TOPICAL REPORT ICUG-001, Revision 2 A-48 May 2003 DRAFT

Original WOG Standard Technical Specification - Ice Bed FOR INFORMATION ONLY I. .-

TOPICAL REPORT ICUG-001, Revision 2 A49 May 2003 DRAFT

3.6 CONTAINMENT SYSTEMS 3.6.15 Ice Bed (Ice Condenser)

LCO 3.6.15 The ice bed shall be OPERABLE.

APPLICABILITY: MODES 1,2,3, and 4.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. Ice bed inoperable. A.1 Restore ice bed to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> OPERABLE status.

B. Required Action and B.1 Be in MODE 3. 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion AND Time not met. B.2 Be in MODE 5. 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.15.1 Verify maximum ice bed temperature is 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> s [27]0 F.

(continued)

TOPICAL REPORT ICUG-001, Revision 2 A-SO May 2003 DRAFT

SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.15.2 Verify total weight of stored ice is > [2,721,600] lb by: 9 months

a. Weighing a representative sample of Ž 144 ice baskets and verifying each basket contains 2 [1400] lb of ice; and

b. Calculating total weight of stored ice, at a 95%

confidence level, using all ice basket weights determined in SR 3.6.15.2.a.

SR 3.6.15.3 Verify azimuthal distribution of ice at a 95% confidence 9 months level by subdividing weights, as determined by SR 3.6.15.2.a, into the following groups:

a. Group 1 -bays I through 8;

b. Group 2- bays 9 through 16; and

c. Group 3- bays 17 through 24.

The average ice weight of the sample baskets in each group from radial rows 1,2, 4, 6, 8, and 9 shall be

> [1400] lb.

SR 3.6.15.4 Verify, by visual inspection, accumulation of ice or - 9 months frost-on Structural members comprising flow channels through the ice condenser is < [0.38] inch thick.

(continued]

TOPICAL REPORT ICUG-001, Revision 2 A-51 May 2003 DRAFT

SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.15.5 Verify by chemical analyses of at least nine [18] months representative samples of stored ice:

a. boron concentration is > [1800] ppm; and

b. pH is 2 [9.0] and s [9.5].

SR 3.6.15.6 Visually inspect, for detrimental structural wear, 40 months cracks, corrosion, or other damage, two ice baskets from each azimuthal group of bays.

See SR 3.6.15.3.

TOPICAL REPORT ICUG-001, Revision 2 A-52 May 2003 DRAFT

B 3.6 CONTAINMENT SYSTEMS B 3.6.15 Ice Bed (Ice Condenser)

BASES BACKGROUND The ice bed consists of over 2,721,600 lb of ice stored in baskets within the ice condenser. Its primary purpose is to provide a large heat sink in the event of a release of energy from a Design Basis Accident (DBA) in containment The Ice would absorb energy and limit containment peak pressure and temperature during the accident transient Umiting the pressure and temperature reduces the release of fission product radioactivity from containment to the environment in the event of a DBA.

The ice condenser is an annular compartment enclosing approximately 300° of the perimeter of the upper containment compartment, but penetrating the operating deck so that a portion extends into the lower containment compartment The lower portion has a series of hinged doors exposed to the atmosphere of the lower containment compartment, which, for normal unit operation, are designed to remain closed. At the top of the ice condenser is another set of doors exposed to the atmosphere of the upper compartment, which also remain closed during normal unit operation. Intermediate deck doors, located below the top deck doors, form the floor of a plenum at the upper part of the ice condenser. These doors also remain closed during normal unit operation. The upper plenum area is used to facilitate surveillance and maintenance of the ice bed.

The ice baskets held Inthe ice bed within the Ice condenser are arranged to promote heat transfer from steam to ice. This arrangement enhances the ice condensers primary function of condensing steam and absorbing heat energy released to the containment during a DBA.

Inthe event of a DBA, the ice condenser inlet doors (located below the operating deck) open due to the pressure rise in the lower compartment. This allows air and steam to flow from the lower compartment into the ice condenser. The resulting pressure Increase within the ice condenser causes the Intermediate deck doors and the top deck doors to open, which allows the air to flow out of the ice condenser into the upper compartment. Steam condensation within the ice condenser limits the pressure and temperature buildup in containment. A divider barrier separates the upper and lower compartments and ensures that the steam is directed Into the ice condenser.

The ice, together with the containment spray, is adequate to absorb the initial blowdown of steam and water from a DBA and the additional heat loads that would enter containment during several hours following the initial blowdown.

The additional heat loads would come from the residual heat in the reactor core, the hot piping and components, and the secondary system, including the steam generators. During the post blowdown period, the Air Retum System (ARS) returns upper compartment air through the divider barrier to the lower TOPICAL REPORT ICUG-001, Revision 2 A-53 May 2003 DRAFT

compartment This serves to equalize pressures in containment and to continue circulating heated air and steam from the lower compartment through the ice condenser where the heat Is removed by the remaining ice.

As Ice melts, the water passes through the ice condenser floor drains into the lower compartment Thus, a second function of the ice bed is to be a large source of borated water (via the containment sump) for long term Emergency Core Cooling System (ECCS) and Containment Spray System heat removal functions in the recirculation mode.

A third function of the ice bed and melted ice Is to remove fission product iodine that may be released from the core during a DBA. Iodine removal occurs during the ice melt phase of the accident and continues as the melted Ice Is sprayed into the containment atmosphere by the Containment Spray System. The ice is adjusted to an alkaline pH that facilitates removal of radioactive iodine from the containment atmosphere. The alkaline pH also minimizes the occurrence of the chloride and caustic stress corrosion on mechanical systems and components exposed to ECCS and Containment Spray System fluids in the recirculation mode of operation.

It is important for the Ice to be uniformly distributed around the 24 Ice condenser bays and for open flow paths to exist around ice baskets. This is especially important during the initial blowdown so that the steam and water mixture entering the lower compartment do not pass through only part of the ice condenser, depleting the ice there while bypassing the Ice in other bays.

Two phenomena that can degrade the ice bed during the long service period are:

a. Loss of ice by melting or sublimation; and

b. Obstruction of flow passages through the Ice bed due to buildup of frost or ice. Both of these degrading phenomena are reduced by minimizing air leakage Into and out of the ice condenser.

The Ice bed limits the temperature and pressure that could be expected following a DBA, thus limiting leakage of fission product radioactivity from containment to the environment.

APPUCABLE The limiting DBAs considered relative to containment SAFETY ANALYSES temperature and pressure are the loss of coolant accident (LOCA) and the steam line break (SLB). The LOCA and SLB are analyzed using computer codes designed to predict the resultant containment pressure and temperature transients. DBAs are not assumed to occur simultaneously or consecutively.

Although the Ice condenser Is a passive system that requires no electrical power to perform Its function, the Containment Spray System and the ARS also function to assist the ice bed in limiting pressures and temperatures. Therefore, TOPICAL REPORT ICUG-001, Revision 2 A-54 May 2003 DRAFT

the postulated DBAs are analyzed In regards to containment Engineered Safety Feature (ESF) systems, assuming the loss of one ESF bus, which is the worst case single active failure and results in one train each of the Containment Spray System and ARS being Inoperable.

The limiting DBA analyses (Ref. 1) show that the maximum peak containment pressure results from the LOCA analysis and is calculated to be less than the containment design pressure. For certain aspects of the transient accident analyses, maximizing the calculated containment pressure is not conservative.

In particular, the cooling effectiveness of the ECCS during the core reflood phase of a LOCA analysis increases with Increasing containment backpressure. For these calculations, the containment backpressure Is calculated In a manner designed to conservatively minimize, rather than maximize, the calculated transient containment pressures, In accordance with 10 CFR 50, Appendix K (Ref. 2). The maximum peak containment atmosphere temperature results from the SLB analysis and is discussed in the Bases for LCO 3.6.5, 'Containment Air Temperature."

In addition to calculating the overall peak containment pressures, the DBA analyses include calculation of the transient differential pressures that occur across subcompartment walls during the initial blowdown phase of the accident transient The internal containment walls and structures are designed to withstand these local transient pressure differentials for the limiting DBAs.

The Ice bed satisfies Criterion 3 of the NRC Policy Statement LCO The ice bed LCO requires the existence of the required quantity of stored ice, appropriate distribution of the ice and the ice bed, open flow paths through the ice bed, and appropriate chemical content and pH of the stored ice. The stored ice functions to absorb heat during a DBA, thereby limiting containment air temperature and pressure. The chemical content and pH of the ice provide core SDM (boron content) and remove radioactive Iodine from the containment atmosphere when the melted ice is recirculated through the ECCS and the Containment Spray System, respectively.

APPLICABILITY In MODES 1, 2, 3, and 4, a DBA could cause an increase In containment pressure and temperature requiring the operation of the Ice bed. Therefore, the LCO is applicable In MODES 1, 2,3, and 4.

In MODES 5 and 6, the probability and consequences of these events are reduced due to the pressure and temperature limitations of these MODES.

Therefore, the ice bed Is not required to be OPERABLE in these MODES.

TOPICAL REPORT ICUG-001, Revision 2 A-55 May 2003 DRAFT

ACTIONS If the Ice bed is inoperable, it must be restored to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />. The Completion Time was developed based on operating experience, which confirms that due to the very large mass of stored Ice, the parameters comprising OPERABILITY do not change appreciably in this time period.

Because of this fact, the Surveillance Frequencies are long (months), except for the ice bed temperature, which is checked every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. If a degraded condition Is Identified, even for temperature, with such a large mass of Ice it is not possible for the degraded condition to significantly degrade further in a 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> period. Therefore, 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> is a reasonable amount of time to correct a degraded condition before initiating a shutdown.

B.1 and B.2 If the ice bed cannot be restored to OPERABLE status within the required Completion Time, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and to MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions In an orderly manner and without challenging plant systems.

SURVEILLANCE SR 3.6.15.1 REQUIREMENTS Verifying that the maximum temperature of the ice bed is s [27]F ensures that the Ice Is kept well below the melting point The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency was based on operating experience, which confirmed that due to the large mass of stored Ice, It is not possible for the Ice bed temperature to degrade significantly within a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> period and was also based on assessing the proximity of the LCO limit to the melting temperature.

Furthermore, the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency is considered adequate in view of Indications in the control room, including the alarm, to alert the operator to an abnormal Ice bed temperature condition. This SR may be satisfied by use of the Ice Bed Temperature Monitoring System.

SURVEILLANCE SR 3.6.15.2 REQUIREMENTS The weighing program is designed to obtain a representative sample of the Ice baskets. The representative sample shall include 6 baskets from each of the 24 Ice condenser bays and shall consist of one basket from radial rows 1, 2, 4, 6.

8, and 9. If no basket from a designated row can be obtained for weighing, a basket from the same row of an adjacent bay shall be weighed.

The rows chosen Include the rows nearest the Inside and outside walls of the ice condenser (rows I and Z and 8 and 9, respectively), where heat transfer into the Ice condenser Is most likely to Influence melting or sublimation. Verifying the TOPICAL REPORT ICUG-001, Revision 2 A-56 May 2003 DRAFT

total weight of ice ensures that there is adequate ice to absorb the required amount of energy to mitigate the DBAs.

Ifa basket is found to contain < 11400] lb of ice, a representative sample of 20 additional baskets from the same bay shall be weighed. The average weight of ice in these 21 baskets (the discrepant basket and the 20 additional baskets) shall be 2 11400] lb at a 95% confidence level.

Weighing 20 additional baskets from the same bay In the event a Surveillance reveals that a single basket contains < 11400] lb ensures that no local zone exists that Is grossly deficient In Ice. Such a zone could experience early melt out during a DBA transient, creating a path for steam to pass through the ice bed without being condensed. The Frequency of 9 months was based on ice storage tests and the allowance built Into the required ice mass over and above the mass assumed in the safety analyses. Operating experience has verified that, with the 9 month Frequency, the weight requirements are maintained with no significant degradation between surveillances.

SURVEILLANCE SR 3.6.15.3 REQUIREMENTS This SR ensures that the azimuthal distribution of ice is reasonably uniform, by verifying that the average ice weight in each of three azimuthal groups of ice condenser bays is within the limit. The Frequency of 9 months was based on Ice storage tests and the allowance built into the required ice mass over and above the mass assumed in the safety analyses. Operating experience has verified that, with the 9 month Frequency, the weight requirements are maintained with no significant degradation between surveillances.

SR 3.6.15.4 This SR ensures that the flow channels through the ice condenser have not accumulated an excessive amount of ice or frost blockage. The visual Inspection must be made for two or more flow channels per Ice condenser bay and must include the following specific locations along the flow channel:

a. Past the lower inlet plenum support structures and turning vanes;

b. Between ice baskets; C. Past lattice frames;

d. Through the intermediate floor grating; and

e. Through the top deck floor grating.

The allowable [0.38] Inch thick buildup of frost or ice Is based on the analysis of containment response to a DBA with partial blockage of the Ice condenser flow passages. If a flow channel In a given bay Is found to have an accumulation of frost or Ice > [0.38] inch thick, a representative sample of 20 additional flow channels from the same bay must be visually inspected.

TOPICAL REPORT ICUG-001, Revision 2 A-57 May 2003 DRAFT

If these additional flow channels are all found to be acceptable, the discrepant flow channel may be considered single, unique, and acceptable deficiency.

More than one discrepant flow channel in a bay is not acceptable, however.

These requirements are based on the sensitivity of the partial blockage analysis to additional blockage. The Frequency of 9 months was based on ice storage tests and the allowance built into the required Ice mass over and above the mass assumed in the safety analyses.

SR 3.6.15.5 Verifying the chemical composition of the stored ice ensures that the stored Ice has a boron concentration of at least [1800] ppm as sodium tetraborate and a high pH, 2 [9.0] and s [9.5], in order to meet the requirement for borated water when the melted ice Is used in the ECCS recirculation mode of operation.

Sodium tetraborate has been proven effective in maintaining the boron content for long storage periods, and it also enhances the ability of the solution to remove and retain fission product Iodine. The high pH Is required to enhance the effectiveness of the Ice and the melted ice in removing iodine from the containment atmosphere. This pH range also minimizes the occurrence of chloride and caustic stress corrosion on mechanical systems and components exposed to ECCS and Containment Spray System fluids in the recirculation mode of operation. The Frequency of [18] months was developed considering these facts

a. Long ice storage tests have determined that the chemical composition of the stored Ice Is extremely stable.

b. Operating experience has demonstrated that meeting the boron concentration and pH requirements has never been a problem; and

c. Someone would have to enter the containment to take the sample, and If the unit Is at power, that person would receive a radiation dose.

SR 3.6.15.6 This SR ensures that a representative sampling of ice baskets, which are relatively thin walled, perforated cylinders, have not been degraded by wear, cracks, corrosion, or other damage. Each ice basket must be raised at least 12 feet for this inspection. The Frequency of 40 months for a visual Inspection of the structural soundness of the ice baskets Is based on engineering judgment and considers such factors as the thickness of the basket walls relative to corrosion rates expected Intheir service environment and the results of the long term ice storage testing.

REFERENCES 1. FSAR, Section [6.2].

2. 10 CFR 50, Appendix K.

TOPICAL REPORT ICUG-001, Revision 2 A-58 May 2003 DRAFT

- -  :~-

/. Topical Report ICUG-001 List of Q}aiies to-the July 2001 Version (rev. 0°to Produce the May 2003 Version (rev. 2)

I- -

The following changes have been incorporated into the republication of topical report ICUG-001 that is dated May 2003 (revision 2). The July 2001 version (revision 0), which was the original fublicationis the official previous version. Revision I to topical report ICUG-001 was not formallyjissued; all changes in that revision have been incorporated in Revision 2.

1., Cover page updated to specify "Revision 2" and "May 2003".

./

-2. Page ii, Table of Contents: Added several headings in Chapters 1 and 2 to reflect changes

- made per reference 27.

• 3. Page iii, List of Figures and Tables: Revised term "sample population" to "sample group" (three places) per reference 19.

4. Page iii, List of Figures and Tables: Revised titles of several tables and figures to reflect changes made per reference 27.

5. Page v, Nomenclature: Revised term "sample populations" to "sample groups" (three places). Revised definition of "Sampling without replacement" to reflect similar clarification, per reference 19.

6. Page 0-1, Active Ice Mass Management: Added following sentence at beginning of second paragraph: "Existing AMIM practices manage each ice basket in the ice bed above the required mean mass supporting the safety analysis." Change per reference 22. -

7. Page 0-2, Industry Challenges: Revised term "sample population" to "sample group" per reference 19.

8. Page 0-3, Industry Challenges: Revised last two paragraphs to read: "A further disparity in the historical methodology required each statistically sampled basket to contain the specified amount of ice, while the Bases allowed for individual baskets to be "light" (i.e., less than the technical specification required minimum mass) if baskets in the local area were sufficiently full. This contradiction also led to differing industry interpretations, even though the original intent was, as described by the technical specification bases, to prevent localized gross degradation of the ice bed. The technical specification methodology presented here treats this contradiction by recognizing that the two primary concerns of the ice mass design basis-and therefore the two required surveillances-re the presence of sufficient total ice mass in the bed distributed appropriately to accommodate the overall DBA response, and a sufficient minimum mass in any individual basket maintained to prevent localized areas of degradation that might challenge the DBA containment pressure response.

"The requirement for the overall DBA response is met by determining total ice mass in the bed based on a sampled group. In this manner, the word "each" is eliminated from the operability requirement, and individual baskets can sublimate during an operating cycle to whatever level their relative position in the ice bed dictates. Conversely, the minimum individual basket mass requirement stipulates a minimum mass of ice for each of the Page I of 5

- A-gn

'a List of Changes to the July 2001 Version (cont.)

statistically sampled baskets so that a minimum amount of ice in the basket is verified to be present. The use of each in this instance is appropriate, since the containment analysis is

- primarily concerned with localized degradation (i.e., a cluster of baskets with degraded mass) and the sampled group is a valid representation of the entire Radial Zone under surveillance.

As noted previously, AIMM practice will manage each basket above the required safety analysis mean, such that no individual basket would be expected to sublimate below this mean value. If a basket sublimates below the safety analysis mean value this instance is identified within the plant's corrective action program, including evaluating AIMM practices to identify the cause and to correct any deficiencies. If a basket sublimates below the minimum individual basket mass requirement, then this condition is TS prohibited, necessitating reporting per the requirements of 10CFR50.73 in addition to corrective action program determination of cause and appropriate corrective actions. Certain individual baskets in the corners of the ice bed would typically pose the greatest challenge to maintaining their stored ice mass above the safety analysis mean, due to the relatively high sublimation rates in these areas. However, AIMM practice would generally identify these baskets for servicing every outage, thereby enabling the ice mass in these baskets to be maintained above the safety analysis mean, which would prevent any challenge to the surveillance requirements."

Changes per references 22 and 27. Also revised term "sample population" to "sample group" (two places) per reference 19.

9. Page 0-3, Summary of Significant Aspects: Clarified that industry commitments to manage the ice mass in each basket above the required technical specification mean, a statistically random sample in each Radial Zone, and a defined minimum individual ice mass per basket combine to become the basis for verification of appropriate ice distribution in lieu of a limited azimuthal row-group surveillance, and deleted reference to minimum blowdown ice mass per reference 22.

10. Page 0-4, Figure 0-1: Revised term in flow diagram "Blowdown Limit" to "Minimum Individual Basket Limit" per reference 22.

11. Page 0-5, Table 0-1: Revised fourth bullet to: "A surveillance for minimum total ice mass in the bed assures the initial conditions of the DBA analyses". Deleted fifth bullet. Revised sixth bullet to: "A surveillance for minimum ice mass in each individual basket prevents localized degradation to avoid any challenge to the DBA containment pressure response". Revised eighth bullet to: "Proper azimuthal distribution of ice in the ice bed is no longer assessed by a separate surveillance requirement; it is implemented through established industry-wide maintenance practices that manage each ice basket above the required safety analysis mean and confirmed through as-found random sampling techniques". Revised ninth bullet to: "All ice baskets in the parent population are subject to random statistical sampling, as opposed to only two-thirds of the population subject to representative sampling." Changes per references 22 and 27.

12. Pages I-l, 1-2, Design Basis: Revised second paragraph to clarify the description of the, original short-term containment pressurization analysis (TMD). Revised third paragraph to clarify the description of the long-term containment pressurization analyses (LOTIC/GOTHIC), and the link to localized degraded regions of ice mass in the bed.

Changes per reference 27.

13. Page 1-2, Design Basis: Revised parenthetical item 2 at end of paragraph to: "enough ice mass is sufficiently distributed such that localized regions of mass degradation do not exist in the ice bed", per reference 27.

Page 2 of 5

- - - -W

-- nhffimv - -

-76.

6 jANNOMW

List of Changeslothotil 260I Version (cont.)

14. Page I-2, Design Basis: Revised fourth paragraph to clarify the use of mass determination uncertainty. Changes per reference 27.

15. Page 1-2, Original Ice Mass Technical Specification Requirements: revised "sample population" to "sample group" (two places), per reference 19.

16. Page I-3, Original Ice Mass Technical Specification Requirements: Revised paragraph under Figure 1-1 to read: "In addition, these masses were used as the verification that a degraded localized region did not exist in the ice bed that would challenge the DBA pressure response. If a basket in the 144-basket statistical sample was found to weigh less than the required individual limit (described as "light'), the sample was to be increased in the localized region (i.e., the affected Bay) by 20 baskets. The averaged mass of the 20 additional baskets and the "light" basket was then required to meet the surveillance limit". Deleted reference to the long-term phase of the DBA in the last sentence on the page. Changes per references 22 and 27.

17. Page I-4, Historical Data: Clarifications for consistency with other sections. Changes per reference 27.

18. Page I-4, Historical Data Analysis: Revised term "sample population" to "sample group",

per reference 19. Minor editorial revisions.

19. Page I-5, Historical Data Analysis: Revised last paragraph to clarify AIMM basis, per reference 27.

20. Page 1-5, AIMM Methodology: Added new section, per reference 27.

21. Page I-6, Determination of Basket Mass in AIMM Practice: Added new section, per reference 27.

22. Page I-6, The Radial Zone Concept: Revised title of section for clarification, per reference 27.

23. Page I-7, The Radial Zone Concept: Clarification revisions for AR-AM description, per reference 27.

24. Page 1-8, Regions of Localized Degraded Mass: Added new section, per reference 27.

25. Page 1-9,

Conclusions:

Editorial revisions made to clarify design basis requirements basis description. Changes per reference 27.

26. Page 1-10,

Conclusions:

Revised first paragraph on page to read, "he minimum individual basket mass surveillance requirement is based on the minimum amount of ice needed in each basket to avoid localized regions of degradation in the ice bed that might challenge the DBA pressure response. This limit is derived from sensitivity runs performed using the three-dimensional GOTHIC analytical code. Concurrent assurance that localized regions ofgross degradation do not exist in the ice bed is given via Active Ice Mass Management (AJMM) methodology, which is based on current industry maintenance practice and asserts that the ice mass in each basket in the ice bed will be managed above the required safety analysis mean, and serviced prior to reaching this limit. Therefore, the methodology for the requirement of minimum individual basket mass has two elements: 1) active maintenance practice (A]MM)

Page 3 of 5

List of Changes to the uiS 2b0I Version (cont.)

that manages each basket to the required safety analysis mean, and 2) a defined surveillance minimum limit of 600 lb per basket." Changes made per reference 27.

27. Page 11-1, Purpose/Scope: Revisions made to description of Section purpose to clarify additional detail regarding alternate mass determination and uncertainty standards. Changes per reference 27.

28. Page II-I, Preferred Ice Mass Determination Method: Revisions made to clarify calibration of load cells. Minor editorial changes. Changes per reference 27.

29. Pages II-1, II-2&II-3, Alternate Ice Mass Determination Methods: Revisions made to add detail regarding the use of alternate mass determination methods. Added description of software projection methodology and visual estimation methodology. Added description of need for industry standard for uncertainty and documentation. Changes per reference 27.

30. Pages 11-3, Standards: Ice Basket Mass Determination Uncertainty: Added new section per reference 27.

31. Page 11-13,

Conclusions:

Revised entire section to reflect the additional detail added to the chapter regarding the development of alternate ice basket mass determination uncertainty and summarize the hierarchy of mass determination techniques, per reference 27.

32. Page 111-1, Purpose/Scope: Editorial changes for consistency, per reference 27.

33. Page m11-2, Ice Mass Statistical Strategy: Revised the term "sample population" to "sample group" (four places). Corrected mislabeled variable in equation for s and in definition of Xi.

Change per reference 19. Added clarification to description of Equation 3.1, per reference 27.

34. Page m-3, Ice Mass Statistical Strategy: Revised term 'sample population" to "sample group", per reference 19. Added clarification to description of Equation 3.2, per reference 27.

35. Page 111-3, Sample Size: Deleted the parenthetical statement "(the probability density function of which is a symmetric bell-shaped curve)", per reference 19.

36. Page m-4, Sample Size: Revised term "sample population" to "sample group" (five places),

per reference 19. Editorial changes per reference 27.

37. Page 1-s, Sample Size: Revised term "sample population" to "sample group" (two places),

per reference 19.

38. Page m-7, Alternate Mass Determination Methods: Revised wording for clarity and consistency. Changes per reference 27.

39. Page m-7, Table 3-1: Revised Note 2 under the table to: "The error values shown may not be equal to the one-sigma random error defined in Equation 3.2. Plant-specific procedures will determine the appropriate value to use in Equation 3.2 and will normally represent two standard deviations for any alternate mass determination method". Changes per reference 19.

40. Page 1I1-9, Alternate Basket Selection Strategy: Revised term "sample population" to "sample group", per reference 19.

Page 4 of 5

List of Changes to t rJti 2001 Version (cont.)

41. Page E-10, Applications of Sampling Plan: Revised term "sample population" to "sample group" (four places), per reference 19.

42. Page 111-1 l, Table 3-3: Revised term "sample population" to "sample group", per reference 19.

43. Pages M-12 through m-15, Table 3-4: Revised term "sample population" to "sample group" (four places, in title), per reference 19.

44. Page R-2,

References:

Added the following sequentially numbered references:

19. ICUG Response to NRC Request for Additional Information, RS Lytton letter to NRC dated June 12, 2002 (w/enclosure).

20. ICUG Response to NRC Request for Additional Information, RS Lytton letter to NRC dated October 10, 2002 (w/enclosure).

21. ICUG Response to NRC Request for Additional Information, RS Lytton letter to NRC dated October 22, 2002 (w/enclosures).

22. ICUG Response to NRC Request for Additional Information, RS. Lytton letter to NRC dated November 26, 2002 (w/enclosures).

23. Everhart, Jerry, DeterminingMass Measurement Uncertainty, January 1997.

24. Abernathy, RB., et al, and Thompson, Jr., J.W., Measurement Uncertainty Handbook January 1980.

25. McClave, James T., and Dietrich, Frank H., A First Course in Statistics, third edition, copyright 1989.

26. Eisenhart, C., Expression of UncertaintiesofFinalResults, PrecisionMeasurement and Calibration,NBS Handbook 91, Vol. I, February 1969.

27. USNRC Draft Safety Evaluation for Ice Condenser Utility Group Topical Report No.

ICUG-001, Revision 0: Application of the Active Ice Mass Management Concept to the Ice CondenserIce Mass Technical Specification, dated May 6, 2003 (w/enclosure).

45. Page A-1, Appendix A: revised "sample population" to "sample group", per reference 19.

46. Page A43, Appendix A: revised "sample population" to "sample group", per reference 19.

47. Page A47, Appendix A: revised "sample population" to "sample group", per reference 19.

48. Added this list of changes to the back.

49. Added a list of attached ICUG-NRC correspondence to the back.

50. Attached ICUG-NRC correspondence (references 19-22, and 27) to the back.

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